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Mold Toxins or Mycotoxins Like T-2 or Trichothecenes
Harm Humans and Mammals

James Schaller Appeals for Physicians to Read About Water Intrusion Illnesses

A "Best Doctor," "Peoples Choice Award MD," and "Top Doctor" according to physicians and patients, appeals for more mold and bacteria attention in sick patients working or living in sick buildings.

1. Toxicol Pathol. 2011 Apr;39(3):502-7. Epub 2011 Mar 11.

T-2 toxin induces degenerative articular changes in rodents: link to Kaschin-Beck disease.

Wang LH, Fu Y, Shi YX, Wang WG.

The Center for Endemic Disease Control, National Center for Disease Prevention and Control, Harbin Medical University, Heilongjiang, China.

Erratum in Toxicol Pathol. 2011 Jun;39(4):747-9.

Osteoarthritis (OA) is a degenerative joint disease that is characterized by joint pain and a progressive loss of articular cartilage. Kaschin-Beck Disease is a form of endemic OA in China whose etiology is unclear, but epidemiological data indicate a possible link to trichothecenes mycotoxin exposure. In vitro, T-2 toxin, a trichothecenes mycotoxin, has been demonstrated to inhibit aggrecan synthesis and promote aggrecanase and pro-inflammatory cytokine production in cultured chondrocytes. To assess the effects of T-2 toxin on articular cartilage in vivo, Wistar rats were fed a diet containing T-2 toxin (100 ng/kg chow) for six and ten months. Following six months of T-2 toxin exposure, histopathological changes in femorotibial cartilage were characterized by chondrocyte degeneration/necrosis and loss, chondrocyte clones, and loss of proteoglycan staining of articular cartilage, sometimes involving the entire thickness of the cartilage in the tibial plateaus and femoral condyles. By ten months, in addition to these changes, there was evidence of cartilage fibration in some rats. In conclusion, T-2 toxin exposure in rats induced degenerative lesions in articular cartilage similar to spontaneous OA, lending support to an etiologic role of mycotoxins in Kaschin-Beck Disease. T-2 toxin-induced degenerative joint disease may be a useful model of metabolic polyarticular OA.

PMID: 21398559 [PubMed - indexed for MEDLINE]

2. Int J Rheum Dis. 2011 Feb;14(1):92-7. doi: 10.1111/j.1756-185X.2010.01568.x. Epub 2010 Aug 23.

Radiographic findings of Wistar rats fed with T-2 toxin and Kashin-Beck disease-affected diet.

Yan D, Kang P, Li Y, Yang J, Shen B, Zhou Z, Deng J, Pei F.

Orthopedics Department, West China Hospital, Sichuan University, Chengdu, China.

OBJECTIVE: To characterize the features of radiographic abnormalities of the tibial bone in Wistar rats which have been fed T-2 toxin and Kashin-Beck disease (KBD) epidemic district food. METHODS: Ninety Wistar rats were divided into five groups. Group A was fed with a normal diet as control; group B was fed with a normal diet and T-2 toxin; group C was fed with a low-nutrition diet and T-2 toxin; group D was fed with a low-nutrition diet; and group E was fed with a KBD-affected diet. At 4, 8 and 12 weeks, six rats from each group were radiographed. After radiographic examination, samples of left knees were harvested and stained with hematoxylin and eosin. RESULTS: At 8 and 12 weeks, there were radiological changes in the epiphyseal plate. Abnormal radiological signs of blurring, thinning and irregularity were seen in groups C and E rats, and the length of tibial bones showed significant difference in the KBD-fed rats and low-nutrition diet combined T-2 toxin rats, compared to the control group rats (P < 0.05). The epiphyseal plates showed more obvious necrosis of chondrocytes in groups C and E. CONCLUSIONS: A rat model of KBD can be established by a KBD-affected diet; proximal epiphyseal plate and metaphyseal bone of the tibia abnormalities on radiographs and histopathology were present in KBD model rats. A low nutrition diet may be involved the aetiology of KBD, and determination of this should be studied in the future.

© 2010 The Authors. International Journal of Rheumatic Diseases © 2010 Asia Pacific League of Associations for Rheumatology and Blackwell Publishing Asia Pty Ltd.

PMID: 21303488 [PubMed - indexed for MEDLINE]

3. Toxicol Lett. 2011 May 10;202(3):168-77. Epub 2011 Feb 4.

T-2 toxin induces apoptosis in ovarian granulosa cells of rats through reactive oxygen species-mediated mitochondrial pathway.

Wu J, Jing L, Yuan H, Peng SQ.

Evaluation and Research Center for Toxicology, Institute of Disease Control and Prevention, Academy of Military Medical Sciences, 20 Dongdajie Street, Fengtai District, Beijing 100071, PR China.

OBJECTIVE: To investigate the reproductive toxicity and cytotoxicity of T-2 toxin, which is a mycotoxin, and to explore its potential apoptotic induction mechanism. METHODS: Ovarian granulosa cells of rats were treated with T-2 toxin (1-100nM) for 24h. The cytotoxicity was assessed with MTT bioassay; apoptotic cells were identified microscopically by chromatin condensation and nuclear fragmentation with Hoechst 33258; mitochondrial membrane potential with hodamine 123 and reactive reactive oxygen species (ROS) with 2',7'-dichlorofluoresceinacetate (DCFH-DA) was analyzed by fluorometry; p53 and other apoptosis-related proteins such as Bax, Bcl-2, caspase-3, caspase-9 were determined by Western blot analysis, and related mRNA expressions were determined by reverse transcriptase-polymerase chain reaction (RT-PCR). The caspase activity was measured by cleavage of the caspase substrate (Ac-DEVD-pNA for caspase-3, Ac-LEHD- pNA for caspase-9). RESULTS: T-2 toxin inhibited the growth of granulosa cells in a concentration-dependent way. The result of Hoechst 33258 staining indicated that T-2 toxin induces granulosa cells apoptosis based on the typical apoptotic morphological changes. Subsequently, we found that T-2 toxin treatment induced ROS accumulation in granulosa cells, resulting in reduction of mitochondrial transmembrane potential. The induction of cell apoptosis was caused by the upregulation of p53, Bax, Bcl-2, Bax/Bcl-2 ration, and the activation of the caspases pathways. T-2 toxin-induced apoptotic granulosa cells significantly decreased through the use of antioxidant Trolox. CONCLUSION: These data suggest a possible underlying molecular mechanism for T-2 toxin that induces the apoptosis signaling pathway in rat granulosa cells by regulation of ROS-mediated mitochondrial pathway.

Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

PMID: 21296132 [PubMed - indexed for MEDLINE]

4. Basic Clin Pharmacol Toxicol. 2011 Jul;109(1):35-41. doi: 10.1111/j.1742-7843.2011.00680.x. Epub 2011 Mar 9.

In vivo antigenotoxicity of baccharin, an important constituent of Baccharis dracunculifolia DC (Asteraceae).

Oliveira PF, Monteiro Neto MA, Leandro LF, Bastos JK, da Silva Filho AA, Tavares DC.

University of Franca, Franca, São Paulo, Brazil Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.

Baccharin (3-prenyl-4-(dihydrocinnamoyloxy)cinnamic acid) is an important chemical compound isolated from the aerial parts of Baccharis dracunculifolia DC (Asteraceae), a native plant of South America, and the most important plant source of Brazilian green propolis. The present study was designed to investigate the ability of baccharin to modulate the genotoxic effects induced by doxorubicin and methyl methanesulphonate in male Swiss mice using the micronucleus and comet assays, respectively. The different doses of baccharin [0.12, 0.24 and 0.48 mg/kg body-weight (b.w.)] were administered simultaneously to doxorubicin (micronucleus test; 15 mg/kg b.w.) and to methyl methanesulphonate (comet assay; 40 mg/kg b.w.). The results showed a significant decrease in the frequency of micronucleated polychromatic erythrocytes in animals treated with baccharin and doxorubicin compared to animals that received only doxorubicin. This reduction ranged from 39.8% to 50.7% in the micronucleus test. The extent of DNA damage in liver cells was significantly lower in animals treated with different concentrations of baccharin combined with methyl methanesulphonate in comparison with the damage observed for animals treated only with methyl methanesulphonate. These differences resulted in a significant reduction in the extent of DNA damage, which ranged from 47.8% to 60.6%.

© 2011 The Authors. Basic & Clinical Pharmacology & Toxicology © 2011 Nordic Pharmacological Society.

PMID: 21266012 [PubMed - indexed for MEDLINE]

5. Mol Nutr Food Res. 2011 May;55(5):761-71. doi: 10.1002/mnfr.201000402. Epub 2011 Jan 24.

Individual and combined effects of subclinical doses of deoxynivalenol and fumonisins in piglets.

Grenier B, Loureiro-Bracarense AP, Lucioli J, Pacheco GD, Cossalter AM, Moll WD, Schatzmayr G, Oswald IP.

INRA, Unité de Pharmacologie-Toxicologie, Toulouse, France.

SCOPE: Deoxynivalenol (DON) and fumonisins (FB) are the most frequently encountered mycotoxins produced by Fusarium species and most commonly co-occur in animal diets. These mycotoxins were studied for their toxicity in piglets on several parameters including plasma biochemistry, organ histopathology and immune response. METHODS AND RESULTS: Twenty-four 5-wk-old animals were randomly assigned to four different groups, receiving separate diets for 5 wk, a control diet, a diet contaminated with either DON (3 mg/kg) or FB (6 mg/kg) or both toxins. At days 4 and 16 of the trial, the animals were subcutaneously immunized with ovalbumin to assess their specific immune response. The different diets did not affect animal performance and had minimal effect on hematological and biochemical blood parameters. By contrast, DON and FB induced histopathological lesions in the liver, the lungs and the kidneys of exposed animals. The liver was significantly more affected when the two mycotoxins were present simultaneously. The contaminated diets also altered the specific immune response upon vaccination as measured by reduced anti-ovalbumin IgG level in the plasma and reduced lymphocyte proliferation upon antigenic stimulation. Because cytokines play a key role in immunity, the expression levels of IL-8, IL-1β, IL-6 and macrophage inflammatory protein-1β were measured by RT-PCR at the end of the experiment. The expression of these four cytokines was significantly decreased in the spleen of piglets exposed to multi-contaminated diet. CONCLUSION: Taken together, our data indicate that ingestion of multi-contaminated diet induces greater histopathological lesions and higher immune suppression than ingestion of mono-contaminated diets.

Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

PMID: 21259430 [PubMed - indexed for MEDLINE]

6. Int J Rheum Dis. 2010 Oct;13(4):406-11. doi: 10.1111/j.1756-185X.2010.01550.x.

Serum levels of IL-1β, IL-6 and TNF-α in rats fed with Kashin-Beck disease-affected diet.

Yan D, Kang P, Shen B, Yang J, Zhou Z, Duan L, Pei F.

Orthopedic Department West China Hospital of Sichuan University, Chengdu, Sichuan, China.

AIM: To investigate the serum level of interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α in rats which have been fed with Kashin-Beck disease (KBD) epidemic district food. METHOD: Two hundred and twenty Wistar rats were divided into five groups. Group A was fed with a normal diet as control; group B was fed with a normal diet and T-2 toxin; group C was fed with a low-nutrition diet and T-2 toxin; group D was fed with a low-nutrition diet; and group E was fed with a KBD-affected diet. The serum bioactivity of IL-1β, IL-6 and TNF-α were tested by enzyme-linked immeunosorbent assay. RESULTS: After 4 weeks, the epiphyseal plate showed more obvious necrosis of chondrocytes in groups B, C and E. Among the KBD-affected feed, normal feed combined with T-2 toxin and low protein combined with T-2 toxin, KBD-affected feed rats had the highest serum levels, and normal feed combined with T-2 toxin group was the lowest. Although the IL-1β, IL-6 and TNF-α levels were no different in the KBD-affected feed compared to low protein combined with T-2 toxin, there were significant differences compared to normal feed combined with the T-2 toxin (P < 0.05). CONCLUSIONS: Serum levels of IL-1β, IL-6 and TNF-α metabolism are altered in the KBD model rats. This effect is relatively similar to the low-nutrition diet combined with the T-2 toxin, which means low-nutrition diet may be involved in the aetiology of KBD.

PMID: 21199478 [PubMed - indexed for MEDLINE]

7. Toxicol Appl Pharmacol. 2011 Feb 1;250(3):299-311. Epub 2010 Nov 11.

The effects of deoxynivalenol on gene expression in the murine thymus.

van Kol SW, Hendriksen PJ, van Loveren H, Peijnenburg A.

RIKILT-Institute of Food Safety, Wageningen University and Research Centre, Wageningen, The Netherlands.

Deoxynivalenol (DON) is a mycotoxin produced by several Fusarium species and is often detected in grains. Because of its high abundance, there has been a large interest in the effects of DON in animals and humans. DON is known to be immunosuppressive at high concentrations and immunostimulatory at low concentrations. The present study aimed to acquire insight into the modes of action of DON. For this, C57Bl6 mice were orally exposed to 5, 10, or 25mg/kg bw DON for 3, 6, or 24h and thymuses were subjected to genome-wide expression microarray analysis. Gene set enrichment analysis (GSEA) demonstrated that DON downregulated genes involved in proliferation, mitochondria, protein synthesis, and ribosomal proteins. Furthermore, GSEA showed a selective downregulation of genes highly expressed at the early precursor thymocytes stage. This indicates that early precursor thymocytes, particularly at the double-positive CD4+CD8+ stage, are more vulnerable to DON than very early or late precursor thymocytes. There was a large overlap of genes upregulated by DON with genes previously reported to be either upregulated during T cell activation or upregulated during negative selection of thymocytes that recognize "self-antigens". This indicates that DON induces cellular events that also occur after activation of the T cell receptor, for example, release of calcium from the endoplasmatic reticulum. This T cell activation in the thymus then evokes negative selection and depletion of thymocytes, which provides a plausible explanation for the high sensitivity of the thymus for DON exposure. The expression patterns of four genes indicative for some of the processes that were affected after DON treatment were confirmed using real-time PCR. Immunocytological experiments with primary mouse thymocytes demonstrated the translocation of NFAT from the cytoplasm into the nucleus upon exposure top DON, thus providing further evidence for the involvement of T cell activation.

Copyright © 2010 Elsevier Inc. All rights reserved.

PMID: 21074547 [PubMed - indexed for MEDLINE]

8. J Anim Sci. 2011 Jan;89(1):124-35. Epub 2010 Oct 1.

Effects of chronic exposure of diets with reduced concentrations of aflatoxin and deoxynivalenol on growth and immune status of pigs.

Chaytor AC, See MT, Hansen JA, de Souza AL, Middleton TF, Kim SW.

Department of Animal Science, North Carolina State University, Raleigh 27695, USA.

This study investigated the growth and immune responses of pigs fed diets containing reduced concentrations of aflatoxin (AF) and deoxynivalenol (DON) from naturally contaminated corn. Sixty gilts (13.9 ± 0.2 kg of BW) were randomly assigned to 4 treatments (5 replicate pens per treatment and 3 pigs per pen): A (a control diet without detectable AF and DON); B (a diet with 60 μg of AF/kg and 300 μg of DON/kg); C (a diet with 120 μg of AF/kg and 600 μg of DON/kg); and D (a diet with 180 μg of AF/kg and 900 μg of DON/kg). Pigs were allowed ad libitum access to feed and water for 33 d. Feed intake and BW were measured weekly and pigs were bled (8 mL) on d 33 to measure the numbers of blood cells, to conduct liver function tests, and to measure immunological variables including IgG, IgM, interferon γ, IL4, IL6, and tumor necrosis factor α. One pig representing the average BW of each pen was killed to obtain the liver, kidneys, and spleen for weight, tissue color measurement, and histological evaluation of tissue damage. When compared with A, pigs in C and D tended to have reduced ADG (0.52 vs. 0.43 and 0.41 kg/d, respectively; P = 0.058) and ADFI (1.04 vs. 0.92 and 0.88 kg/d, respectively; P = 0.061). White blood cell count of pigs in D (23.4 × 10(3) cells/μL) was greater (P < 0.05) than those in A, B, and C (18.4, 18.5, and 16.8 × 10(3) cells/μL, respectively. Serum tumor necrosis factor α concentration of pigs in D (335 pg/mL) differed (P < 0.05) from those in A and C (299 and 290 pg/mL, respectively). Pigs in B and D had greater (P < 0.05) fibrosis in liver tissues than those in A. Collectively, this study shows that diets containing both AF and DON greater than 60 and 300 μg/kg, respectively, may reduce growth and decrease feed intake, whereas diets containing 120 μg of AF/kg and 600 μg of DON/kg may result in altered immune health, systemic inflammation, and partial liver damage, causing further reduction in growth of pigs.

PMID: 20889686 [PubMed - indexed for MEDLINE]

9. J Nutr. 2010 Nov;140(11):1956-62. Epub 2010 Sep 22.

Deoxynivalenol impairs porcine intestinal barrier function and decreases the protein expression of claudin-4 through a mitogen-activated protein kinase-dependent mechanism.

Pinton P, Braicu C, Nougayrede JP, Laffitte J, Taranu I, Oswald IP.

Laboratoire de Pharmacologie et Toxicologie UR66, INRA, F-31931 Toulouse, France.

Deoxynivalenol (DON) is a common mycotoxin that contaminates cereals and their by-products. The gastrointestinal tract is the first physical barrier against ingested food contaminants. DON contributes to the loss of barrier function of the intestine through the decreased expression of claudin-4 protein, a tight junction protein. The mechanism by which DON alters the intestinal barrier function remains poorly characterized. Therefore, we investigated the involvement of mitogen-activated protein kinases (MAPK) in the DON-induced loss of barrier function. We first verified that 30 μmol/L of DON activated MAPK in a highly sensitive porcine intestinal epithelial cell line (IPEC-1). Inhibition of p44/42 extracellular signal-regulated kinase (ERK) phosphorylation, with 0.5 μmol/L of the specific MAPK pharmacological inhibitor U0126 for 2 h, restored the barrier function of the differentiated intestinal epithelial cell monolayers. The restoration of barrier function was evaluated by trans-epithelial electrical resistance measurements and tracer flux paracellular permeability experiments. The U0126 also restored the intestinal expression of claudin-4 protein, thereby demonstrating that MAPK activation is involved in claudin-4 protein expression and claudin-4 is involved in the maintenance of the intestinal epithelial cell barrier function. Further experiments indicated that p44/42 ERK is not involved in the transcriptional regulation of claudin-4. In conclusion, we demonstrated that DON-induced activation of the p44/42 ERK signaling pathway inhibits the expression of claudin-4 protein, which leads to impaired intestinal barrier function. Given the high levels of DON in cereal grains, these observations of impaired barrier function have implications for human and animal health.

PMID: 20861219 [PubMed - indexed for MEDLINE]

10. J Appl Toxicol. 2010 Aug;30(6):566-73.

Comparative hepatotoxicity of deoxynivalenol in rat, mouse and human liver cells in culture.

Sahu SC, O'Donnell MW Jr, Wiesenfeld PL.

Division of Toxicology, Office of Applied Research and Safety Assessment, Center for Food Safety and Applied Nutrition, US Food and Drug Administration, Laurel, MD 20708, USA.

The present study was undertaken to assess, in vitro, the hepatotoxic potential of the food-borne mycotoxin, deoxynivalenol (DON), using rat (Clone9 and MH1C1), mouse (NBL CL2) and human (WRL68 and HepG2) liver cells in culture. The cells were treated with DON for 24 h at 37 degrees C in 5% CO(2) at concentrations of 0-25 microg ml(-1). Following the treatment period, the cells were assayed for biochemical markers of hepatotoxicity that included three independent cytotoxicity assays, oxidative stress and mitochondrial dysfunction. Concentration-dependent cytotoxicity of DON was observed in each of the five different liver cells derived from three different species (rat, mouse and human) over the entire concentration range studied, beginning at 0.1 microg ml(-1). At these concentrations DON did not induce a biologically significant increase in oxidative stress in these liver cells, and showed a significant decrease in the mitochondrial function only in the rat liver MH1C1 cells compared with the control. The results of this in vitro study suggest that DON is a potential hepatotoxin for the rat, mouse and human liver cells in the concentration range tested in this study. The liver cells used in this study showed distinct endpoint-sensitivity to DON related to the species.

(c) 2010 by John Wiley and Sons, Ltd.

PMID: 20809545 [PubMed - indexed for MEDLINE]

11. Toxicol Lett. 2010 Nov 10;199(1):43-50. Epub 2010 Aug 12.

Impact of DUSP1 on the apoptotic potential of deoxynivalenol in the epithelial cell line HepG2.

Casteel M, Nielsen C, Kothlow S, Dietrich R, Märtlbauer E.

Department of Veterinary Sciences, Ludwig-Maximilians-University of Munich, Schönleutnerstrasse 8, 85764 Oberschleissheim, Germany.

The trichothecene deoxynivalenol (DON) is the most common mycotoxin contaminant of cereal-based food products. Several studies revealed DON as a potent inducer of the three major mitogen-activated protein kinases (MAPKs). Until now, little is known about the role of negative regulators of MAPK pathway in the cellular response to DON. In this report we evaluated, for the first time, the impact of mitogen-activated protein kinase phosphatases (MKPs), particularly dual specific phosphatase 1 (DUSP1), on the toxic potential of DON in the epithelial cell line HepG2. Our results indicate that both low and high concentrations of DON trigger a strong and sustained DUSP1 mRNA and protein expression, mediated by the sustained activation of MEK/ERK pathway. Furthermore, the expression of DUSP1 protein correlates with the inactivation of JNK1/2, whereas a sustained activation of p38 and ERK1/2 was observed in the presence of DON. In contrast, treatment of DUSP1 knock-down cells with DON triggers a prolonged activation of JNK1/2, which leads to the induction of apoptosis. Taken together, we propose DUSP1 as a novel target gene of DON, which is essential for the prevention of DON induced apoptosis in the epithelial cell line HepG2.

Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

PMID: 20708668 [PubMed - indexed for MEDLINE]

12. Int J Rheum Dis. 2010 Aug;13(3):266-72.

The effect of Kashin-Beck disease-affected feed and T-2 toxin on the bone development of Wistar rats.

Yan D, Kang P, Yang J, Shen B, Zhou Z, Duan L, Deng J, Huang H, Pei FX.

Orthopedics Department, West China Hospital, Sichan University, Chengdu, 610041, China.

OBJECTIVE: To investigate the effect of Kashin-Beck disease (KBD)-affected feed and T-2 toxin on the bone development of Wistar rats. METHODS: Seventy-eight ablactation Wistal rats (50% male and 50% female) weighing approximately 65 g were obtained from Sichuan Medical Center (Chengdu, China), and were randomly assigned to three groups (Groups A, B and C). Group A had 24 rats and were fed with commercial rat feed (control); Group B had 30 rats and were fed with commercial rat feed and T2 toxin by intragastric administration; and Group C had 24 rats and were fed with the KBD-affected feed. The histological sections were stained with hematoxylin and eosin (H&E) and Masson dye. RESULTS: Weight gain was fastest Group A rats and Group C rats had the lowest weight gain (P < 0.05). There were no epiphyseal plate chondrocyte necroses in the control group at the first, second, and fourth weeks. In the T-2 toxin group, two rats had chondrocyte-focus necroses at the labrocyte cell zone at the second week. At the fourth week, six rats had chondrocyte-focus or lamellar necroses at the labrocyte cell zone. Three rats had focus necrosis at the proliferation cell zone, and there were three rats with penetration necrosis. In the KBD-affected group, one rat had chondrocyte-focus necrosis at the labrocyte cell zone at the second week and seven rats had chondrocyte-focus necrosis at the labrocyte cell zone at the fourth week. And at the same time, two rats had focus necrosis at the proliferation cell zone, three rats had lamellar necrosis at the labrocyte cell zone, four had focus necrosis at the labrocyte cell zone, and two rats had penetration necrosis. The epiphyseal plate Masson dye of the control group showed deep blue collogen coloration and in the KBD-affected group and T-2 toxin group, collogen showed a pale blue color, the drum dyeing was uneven, and the collogen was showed an absence of color in the region of the necrosis. CONCLUSIONS: With KBD-affected feed or T-2 toxin intervention, rats had focus necrosis and lamellar necrosis at the epiphyseal plate. KBD-affected feed rats had less weight gain than T-2 toxin intervention rats, which means there were other etiological factors in KBD-affected feed.

PMID: 20704625 [PubMed - indexed for MEDLINE]

13. J Immunotoxicol. 2010 Jul-Sep;7(3):147-56.

Protein expression profiling of mouse thymoma cells upon exposure to the trichothecene deoxynivalenol (DON): implications for its mechanism of action.

Osman AM, Pennings JL, Blokland M, Peijnenburg A, van Loveren H.

National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands.

The objective of this work was to investigate whether proteomic analysis of thymoma cells treated with the trichothecene deoxynivalenol (DON) as compared to non-treated (control) cells would reveal differential protein expression, and thus would contribute to a better understanding of the mechanisms of its toxicity. For that purpose the mouse thymoma cell line EL4 was exposed to 0.5 microM DON for 6 hr. A total of 30 proteins were affected after exposure of EL4 cells to DON. Most of these proteins were up-regulated and included key metabolic enzymes (e.g., fatty acid synthase, aldose reductase, carbamoyl phosphate synthetase, glucose-6-phosphate isomerase), chaperones (e.g., HSP9AB1 and HSP70), enzymes implicated in protein folding (PDI and ERO1-l alpha), and proteins involved in protein degradation (ubiquitin-conjugating enzyme (E1) and proteasome subunit alpha type-1). In addition, an IgE-binding protein with a molecular weight of 60 kDa and My-binding protein 1a (MYBBP1A), a transcription factor, were found to be up-regulated by DON. The observed up-regulation of MYBBP1A, a known repressor of a number of transcription factors such as PGC-1 alpha, C-myb, and p65 of the NF-kappaB family, suggests that this protein might play a role in the mechanism of DON toxicity.

PMID: 20672443 [PubMed - indexed for MEDLINE]

14. Toxicol In Vitro. 2010 Oct;24(7):1890-8. Epub 2010 Jul 13.

Physio-pathological parameters affect the activation of inflammatory pathways by deoxynivalenol in Caco-2 cells.

Van De Walle J, During A, Piront N, Toussaint O, Schneider YJ, Larondelle Y.

Institut des Sciences de la Vie, UCLouvain, B 1348 Louvain-la-Neuve, Belgium.

The intake of deoxynivalenol (DON), a mycotoxin contaminating cereal food items, causes gastro-intestinal illness in human and animal. This study investigated whether intracellular inflammatory cascades (MAPKs and NF-κB), cell maturity (proliferating vs. differentiated), cell state (control vs. inflamed) and exposure duration (chronic vs. acute) affect IL-8 secretion and PGE-2 synthesis in Caco-2 cells exposed to plausible intestinal concentrations (50, 500 and 5000 ng/ml) of DON. IL-8 secretion and PGE-2 synthesizing capacity were dose-dependently upregulated in differentiated Caco-2 cells exposed to DON during 24h, reaching an increase of ∼25 and 1.7-fold respectively, whereas transcript level of IL-8 and COX-2 were increased by ∼40 and 17-fold. Similar results were obtained with proliferating cells. The upregulation decreased upon simultaneous incubation with inhibitors of MAPKs ERK1/2 or p38 or of transcription factor NF-κB. IL-8 secretion and PGE-2 synthesizing capacity increased respectively by ∼15 and 2-fold after chronic 21 day incubation with DON (50 ng/ml). IL-8 production was exacerbated (∼510-fold versus negative control) upon simultaneous exposure to inflammatory stimuli. These results suggest activation of inflammatory pathways in intestinal epithelial cells exposed chronically or acutely to DON. The sensitivity to DON, whereas not affected by cell differentiation, is exacerbated by the presence of additional stimuli.

Copyright © 2010 Elsevier Ltd. All rights reserved.

PMID: 20633634 [PubMed - indexed for MEDLINE]

15. Toxicol Pathol. 2010;38(3):429-51.

Neurotoxic, inflammatory, and mucosecretory responses in the nasal airways of mice repeatedly exposed to the macrocyclic trichothecene mycotoxin roridin A: dose-response and persistence of injury.

Corps KN, Islam Z, Pestka JJ, Harkema JR.

Comparative Medicine and Integrative Biology, Michigan State University, East Lansing, MI 48824, USA.

Macrocyclic trichothecene mycotoxins encountered in water-damaged buildings have been suggested to contribute to illnesses of the upper respiratory tract. Here, the authors characterized the adverse effects of repeated exposures to roridin A (RA), a representative macrocyclic trichothecene, on the nasal airways of mice and assessed the persistence of these effects. Young, adult, female C57BL/6 mice were exposed to single daily, intranasal, instillations of RA (0.4, 2, 10, or 50 microg/kg body weight [bw]) in saline (50 microl) or saline alone (controls) over 3 weeks or 250 microg/kg RA over 2 weeks. Histopathologic, immunohistochemical, and morphometric analyses of nasal airways conducted 24 hr after the last instillation revealed that the lowest-effect level was 10 microg/kg bw. RA exposure induced a dose-dependent, neutrophilic rhinitis with mucus hypersecretion, atrophy and exfoliation of nasal transitional and respiratory epithelium, olfactory epithelial atrophy and loss of olfactory sensory neurons (OSNs). In a second study, the persistence of lesions in mice instilled with 250 microg/kg bw RA was assessed. Nasal inflammation and excess luminal mucus were resolved after 3 weeks, but OSN loss was still evident in olfactory epithelium (OE). These results suggest that nasal inflammation, mucus hypersecretion, and olfactory neurotoxicity could be important adverse health effects associated with short-term, repeated, airborne exposures to macrocyclic trichothecenes.

PMID: 20430879 [PubMed - indexed for MEDLINE]

16. Free Radic Biol Med. 2010 Jul 1;49(1):50-60. Epub 2010 Mar 27.

Lutein protects HT-29 cells against Deoxynivalenol-induced oxidative stress and apoptosis: prevention of NF-kappaB nuclear localization and down regulation of NF-kappaB and Cyclo-Oxygenase-2 expression.

Krishnaswamy R, Devaraj SN, Padma VV.

School of Biotechnology and Genetic Engineering, Bharathiar University, Coimbatore - 641046, India.

Increasing evidence suggests that oxidative stress is closely linked to toxic responses in cells. The tricothecene mycotoxin, Deoxynivalenol (DON), primarily affects cells of the immune system and the GI tract. DON's cytotoxicity is closely linked to intracellular ROS, and it exerts its toxic effect by a mechanism known as ribotoxic stress response, which drives both cytokine expressions at low dosages and apoptosis at high dosages. Studies to alleviate DON's toxicity are sparsely reported in literature. In the present study, the cytoprotective effect of lutein, was tested in HT-29 cells against DON-induced oxidative stress and cytotoxicity. MTT assay revealed IC(20) values of DON at 250 ng/ml. Pre-treatment of cells with 10 microM lutein resulted in 95% cell viability. Lutein combated DON-induced oxidative stress and downregulated expression of inflammatory genes, NF-kappaB and COX-2. Lutein also prevented DON-induced migration of NF-kappaB into the nucleus, as measured by immunofluorescence. Morphological studies by Electron microscopy and Cell cycle analysis by flow cytometry indicated that lutein prevented DON-induced apoptosis. The results of the present study demonstrate for the first time that lutein exerts a cytoprotective role in DON-induced toxicity.

(c) 2010 Elsevier Inc. All rights reserved.

PMID: 20347963 [PubMed - indexed for MEDLINE]

17. Int Orthop. 2010 Dec;34(8):1351-6. Epub 2010 Feb 19.

Study on the effect of T-2 toxin combined with low nutrition diet on rat epiphyseal plate growth and development.

Yao YF, Kang PD, Li XB, Yang J, Shen B, Zhou ZK, Pei FX.

Orthopedic Department, West China Hospital, Sichuan University, Chengdu, People's Republic of China.

The purpose of this study was to observe early lesions of rat epiphyseal plates and metaphysis caused by T-2 toxin and T-2 toxin combined with a low nutrition diet to determine possible pathogenic factors of Kashin-Beck disease (KBD). Ninety Wistar rats were divided into three groups. Group A was fed with a normal diet as control; group B was fed with a normal diet and T-2 toxin; and group C was fed with a low nutrition diet and T-2 toxin. The left knee specimens were collected, fixed in formaldehyde solution, stained by hematoxylin and eosin and Masson. After two weeks, the epiphyseal plate showed necrosis of chondrocytes in groups B and C. After four weeks, more obvious chondrocyte necrosis appeared. The positive rate of Lamellar necrosis in group C was significantly higher than that in groups B and A (P < 0.01). Metaphyseal trabecular bone showed sparse disorder and disruption in group C. T-2 toxin combined with a low nutrition diet could lead to more serious chondrocyte necrosis in the epiphyseal plate and disturb metaphyseal trabecular bone formation.

PMCID: PMC2989057 PMID: 20169345 [PubMed - indexed for MEDLINE]

18. Toxicol Sci. 2010 May;115(1):140-55. Epub 2010 Feb 11.

DNA damage and DNA damage responses in THP-1 monocytes after exposure to spores of either Stachybotrys chartarum or Aspergillus versicolor or to T-2 toxin.

Rakkestad KE, Skaar I, Ansteinsson VE, Solhaug A, Holme JA, Pestka JJ, Samuelsen JT, Dahlman HJ, Hongslo JK, Becher R.

Department of Air Pollution and Noise, Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo, Norway.

We have characterized cell death in THP-1 cells after exposure to heat-treated spores from satratoxin G-producing Stachybotrys chartarum isolate IBT 9631, atranone-producing S. chartarum isolate IBT 9634, and sterigmatocystin-producing Aspergillus versicolor isolate IBT 3781, as well as the trichothecenes T-2 and satratoxin G. Spores induced cell death within 3-6 h, with Stachybotrys appearing most potent. IBT 9631 induced both apoptosis and necrosis, while IBT 9634 and IBT 3781 induced mostly necrosis. T-2 toxin and satratoxin G caused mainly apoptosis. Comet assay +/- formamidopyrimidine DNA glycosylase showed that only the spore exposures induced early (3h) oxidative DNA damage. Likewise, only the spores increased the formation of reactive oxygen species (ROS), suggesting that spores as particles may induce ROS formation and oxidative DNA damage. Increased Ataxia Telangiectasia Mutated (ATM) phosphorylation, indicating DNA damage, was observed after all exposures. The DNA damage response induced by IBT 9631 as well as satratoxin G was characterized by rapid (15 min) activation of p38 and H2AX. The p38 inhibitor SB 202190 reduced IBT 9631-induced H2AX activation. Both IBT 9631 and T-2 induced activation of Chk2 and H2AX after 3 h. The ATM inhibitor KU 55933, as well as transfection of cells with ATM siRNA, reduced this activation, suggesting a partial role for ATM as upstream activator for Chk2 and H2AX. In conclusion, activation of Chk2 and H2AX correlated with spore- and toxin-induced apoptosis. For IBT 9631 and satratoxin G, additional factors may be involved in triggering apoptosis, most notably p38 activation.

PMCID: PMC2902923 PMID: 20150440 [PubMed - indexed for MEDLINE]

19. J Toxicol Environ Health A. 2009;72(20):1242-51.

Purification and comparative neurotoxicity of the trichothecenes satratoxin G and roridin L2 from Stachybotrys chartarum.

Islam Z, Shinozuka J, Harkema JR, Pestka JJ.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing, Michigan 48824-1224, USA.

Satratoxin G (SG), a macrocyclic trichothecene produced by Stachybotrys chartarum, induces apoptosis in cultured neuronal cells as well as nasal olfactory sensory neurons (OSN) in the nose and brain of mice exposed intranasally to this toxin. The purposes of this study were to (1) develop a facile method for production and purification of both SG and its putative biosynthetic precursor, roridin L2 (RL2), from S. chartarum cultures and (2) compare their relative neurotoxicity in vitro and in vivo. Stachybotrys chartarum 29-58-17 was cultured in Fernbach flasks on rice (5 x 10(5) spores/250 g rice) for 4 to 6 wk. Following extraction with acetonitrile, the extract was dried, dissolved in dichloromethane, and subjected to Michel-Miller silica-gel chromatography using a stepwise acetonitrile-dichloromethane gradient with SG and RL2 eluting in the 30 and 40% acetonitrile fractions, respectively. Purification of the two compounds was completed by C18 semipreparative reverse-phase liquid chromatography using an acetonitrile-water gradient, and purity was confirmed by electrospray ionization/collision-induced dissociation (ESI-CID) tandem mass spectroscopy. Although viability significantly decreased in PC-12 neuronal cells treated with 10 to 25 ng/ml of SG, RL2 at concentrations up to 1000 ng/ml was not toxic. Flow cytometry and agarose DNA fragmentation assays revealed that SG at 10 to 25 ng/ml induced apoptotic death in the PC-12 cells, while RL2 at concentrations up to 1000 ng/ml was without effect. In a similar fashion, intranasal exposure of mice (female B6C3F1) to SG at 100 microg/kg body weight (bw) induced marked OSN apoptosis and atrophy of the olfactory epithelium, whereas RL2 at the equivalent dose did not exhibit toxicity. Taken together, an optimized protocol for production and isolation of trichothecenes from S. chartarum cultures is described and further demonstrates that while the macrocyclic SG was neurotoxic in vitro and in vivo, its biosynthetic precursor, RL2, was nontoxic.

PMCID: PMC2808125 PMID: 20077192 [PubMed - indexed for MEDLINE]

20. Arh Hig Rada Toksikol. 2009 Dec;60(4):401-9.

Inflammatory and haematotoxic potential of indoor Stachybotrys chartarum (Ehrenb.) Hughes metabolites.

Piecková E, Hurbánková M, Cerná S, Lisková A, Kováciková Z, Kolláriková Z, Wimmerová S.

Slovak Medical University, Bratislava, Slovakia.

Mould Stachybotrys chartarum (Ehrenb.) Hughes is known to pose a health risk in indoor environments. Most of its strains can produce several intra- and extracellular trichothecene mycotoxins. Complex secondary metabolites of stachybotrys isolates from mouldy dwellings/public buildings in Slovakia were intratracheally instilled in Wistar male rats (4 microg in 0.2 mL of 0.2 % dimethylsulphoxide; diacetoxyscirpenol as the positive control). After three days, haematological parameters were measured in peripheral blood and inflammatory response biomarkers in bronchoalveolar lavage fluid (BALF), and the results were statistically analysed. Exometabolites proved to suppress red blood cell (RBC), decreasing the total RBC count, haemoglobin, and haematocrit. The exposed rats showed significantly higher total BALF cell count, indicating inflammation, lower alveolar macrophage counts, and increased granulocyte count related to the BALF cells. Due to haematotoxic and inflammation-inducing properties, metabolites of S. chartarum can cause damage to the airways and haematological disorders in occupants of mouldy buildings.

PMID: 20061240 [PubMed - indexed for MEDLINE]

21. Vet Rec. 2009 Dec 12;165(24):713-8.

Effects of a deoxynivalenol-contaminated diet on the reproductive performance and immunoglobulin concentrations in pigs.

Jakovac-Strajn B, Vengust A, Pestevsek U.

Institute for Hygiene and Pathology of Animal Nutrition, Veterinary Faculty, University of Ljubljana, Gerbiceva 60, 1000 Ljubljana, Slovenia.

Two groups of 10 pregnant gilts (89 +/- 2 days gestation) were fed either an experimental diet that contained 5.08 mg/kg deoxynivalenol, 0.09 mg/kg zearalenone and 21.6 mg/kg fusaric acid, or a control diet that contained 0.29 mg/kg deoxynivalenol, <0.02 mg/kg zearalenone and <0.77 mg/kg fusaric acid. The concentrations of immunoglobulins were measured in sera of the gilts and in the colostrum and serum of the piglets by radial immunodiffusion. The feed consumption of the sows fed the experimental diet was significantly lower and the overall growth rate of their piglets was significantly reduced. On average, parturition took 80 minutes longer in sows fed the experimental diet. On day 17 after parturition, the concentration of IgM in the serum of the experimental gilts was significantly higher, but the concentration of IgA in their colostrum was significantly lower, than in the control gilts. In the serum of the piglets 12, 24 and 48 hours after first suckling, the concentrations of IgA and IgG were significantly lower in those farrowed by the sows fed the experimental diet than in those farrowed by the sows fed the control diet.

PMID: 20008344 [PubMed - indexed for MEDLINE]

22. Exp Toxicol Pathol. 2011 Jan;63(1-2):17-24. Epub 2009 Sep 27.

Rapid deposition of glomerular IgA in BALB/c mice by nivalenol and its modifying effect on high IgA strain (HIGA) mice.

Dewa Y, Kemmochi S, Kawai M, Saegusa Y, Harada T, Shimamoto K, Mitsumori K, Kumagai S, Sugita-Konishi Y, Shibutani M.

Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan.

To clarify the underlying mechanisms of IgA nephropathy (IgAN) induced by nivalenol (NIV), a trichothecene mycotoxin, we examined the time and dose relationships of glomerular deposition of IgA by NIV in BALB/c mice (Experiment 1), and also evaluated the modification of NIV on spontaneous IgAN in an inbred murine model, a high IgA strain (HIGA), during its early stage of pathogenesis (Experiment 2). In Experiment 1, female BALB/c mice were given a diet containing 0, 12, or 24 ppm concentration of NIV for 4 or 8 weeks. An increase in serum IgA levels was found at 24 ppm from 4 weeks. At week 8 of treatment, dose-dependent increases in serum IgA levels and glomerular deposition of IgA and IgG were observed without accompanying histopathological glomerular changes. On the other hand, in Experiment 2, control HIGA mice exhibited rather high levels of serum IgA as compared with BALB/c mice from 4 weeks of experiment as well as glomerular deposition of IgA and IgG and mesangial proliferation as revealed at week 8. NIV at 24ppm further increased serum IgA in this strain; however, it did not enhance glomerular immunoglobulin deposition or histopathological lesion. These results suggest that NIV-induced increase of serum IgA levels may be primarily responsible for glomerular immunoglobulin deposition; however, NIV does not enhance glomerular IgA deposition that may lead to exacerbation of predisposed IgAN in the short term, irrespective of the further elevation of serum IgA from the high basal levels.

Copyright © 2009 Elsevier GmbH. All rights reserved.

PMID: 19783131 [PubMed - indexed for MEDLINE]

23. Wei Sheng Yan Jiu. 2009 Jul;38(4):408-12.

[Effects of deoxynivalenol on apoptosis of human gastric carcinoma cell line SGC-7901, BGC-823 in vitro].

[Article in Chinese]

Liu J, Xing X, Xing L, Zhou B.

Laboratory of Experimental Pathology, Hebei Medical University, Shijiazhuang 050017, China.

OBJECTIVE: To explore the putative effects and possible mechanisms of deoxynivalenol (DON) on the apoptosis of human gastric carcinoma cell line SGC-7901, BGC-823 in vitro. METHODS: SGC-7901 and BGC-823 cells were treated with DON (50, 100, 1000 microg/L) for 72 hours, and then cells were harvested for the studies of apoptosis and the expression of Bax and Bcl-2 with flow cytometry (FCM), immunocytochemical staining and Western blot. RESULTS: FCM results showed that the apoptosis rates of SGC-7901 and BGC-823 cells in DON treatment groups were higher than that in control, and positive dose-effect correlations could be found in both cell lines (SGC-7901: r = 0.660, P < 0.05, n=4, BGC-823: r = 0.750, P < 0.01, n=4). FCM, immunocytochemical staining and Western blot results showed that the expression of Bax was increased while that of Bcl-2 was decreased in DON treatment groups of SGC-7901 and BGC-823. CONCLUSION: The results suggested that DON could induce apoptosis of SGC-7901, BGC-823 cells in vitro in a dose-dependent manner, and possible mechanisms may be increased formation of Bax-Bax homology dimer and decreased formationof Bax-Bcl-2 dimer by up-regulation of the expression of Bax and down-regulation of that Bcl-2.

PMID: 19689068 [PubMed - indexed for MEDLINE]

24. Toxicology. 2009 Oct 1;264(1-2):104-9. Epub 2009 Aug 5.

Pathway of deoxynivalenol-induced apoptosis in human colon carcinoma cells.

Bensassi F, El Golli-Bennour E, Abid-Essefi S, Bouaziz C, Hajlaoui MR, Bacha H.

Laboratory of Research on Biologically Compatible Compounds, Faculty of Dentistry, Rue Avicenne, 5019 Monastir, Tunisia.

The mycotoxin, deoxynivalenol (DON), is generally detected in cereal grains and grain-based food products worldwide. Therefore, DON has numerous toxicological effects on animals and humans. The present investigation was conducted to determine the molecular aspects of DON toxicity on human colon carcinoma cells (HT 29). To this aim, we have monitored the effects of DON on (i) cell viability, (ii) Heat shock protein expressions as a parameter of protective and adaptive response, (iii) oxidative damage and (iv) cell death signalling pathway. Our results clearly showed that DON treatment inhibits cell proliferation, did not induce Hsp 70 protein expression and reactive oxygen species generation. We have also demonstrated that this toxin induced a DNA fragmentation followed by p53 and caspase-3 activations. Finally, our findings suggested that oxidative damage is not the major contributor to DON toxicity. This mycotoxin induces direct DNA lesions and could be considered by this fact as a genotoxic agent inducing cell death via an apoptotic process.

2009 Elsevier Ireland Ltd.

PMID: 19664677 [PubMed - indexed for MEDLINE]

25. Toxicol In Vitro. 2009 Dec;23(8):1580-4. Epub 2009 Jul 14.

Development of a pig jejunal explant culture for studying the gastrointestinal toxicity of the mycotoxin deoxynivalenol: histopathological analysis.

Kolf-Clauw M, Castellote J, Joly B, Bourges-Abella N, Raymond-Letron I, Pinton P, Oswald IP.

Université de Toulouse, Ecole Nationale Vétérinaire (ENVT), 23 chemin des Capelles, BP 87614, 31300 Toulouse Cedex 3, France.

The digestive tract is a target for the mycotoxin deoxynivalenol (DON), a major cereals grain contaminant of public health concern in Europe and North America. Pig, the most sensitive species to DON toxicity, can be regarded as the most relevant animal model for studying the intestinal effects of DON. A pig jejunal explants culture was developed to assess short-term effects of DON. In a first step, jejunal explants from 9-13 week-old and from 4-5 week-old pigs were cultured in vitro for up to 8h. Explants from younger animals were better preserved after 8h, as assessed by morphological scores and by villi lengths. In a second step, DON dose-related alterations of the jejunal tissue were observed, including shortened and coalescent villi, lysis of enterocytes, oedema. After 4h of DON exposure of explants from 4-5 week-old pigs, a no-effect concentration level of 1 microM was estimated (corresponding to diet contaminated with 0.3mg DON/kg) based on morphological scores, and of 0.2 microM based on villi lengths. In conclusion, our data indicate that pig intestinal explants represent a relevant and sensitive model to investigate the effects of food contaminants.

PMID: 19607908 [PubMed - indexed for MEDLINE]

26. Toxicol Sci. 2009 Aug;110(2):363-75. Epub 2009 Jun 18.

Fusarial toxin-induced toxicity in cultured cells and in isolated mitochondria involves PTPC-dependent activation of the mitochondrial pathway of apoptosis.

Bouaziz C, Martel C, Sharaf el dein O, Abid-Essefi S, Brenner C, Lemaire C, Bacha H.

Laboratory of Research on Biologically Compatible Compounds, Faculty of Dentistry, Monastir 5000, Tunisia.

Mycotoxins produced by the Fusarium molds can cause a variety of human diseases and economic losses in livestock. Fusaria produce predominantly two types of mycotoxins: the nonestrogenic trichothecenes including T-2 toxin and the mycoestrogens such as zearalenone (ZEN). In a previous report, we demonstrated that the hepatotoxicity of these mycotoxins involves the mitochondrial pathway of apoptosis. Here, we observed that both fusarotoxins induced cell death by a mitochondria-dependent apoptotic process which includes opening of the mitochondrial permeability transition pore complex (PTPC), loss of mitochondrial transmembrane potential, increase in O(2)(.-) production, mitochondrial relocalization of Bax, cytochrome c release, and caspase activation. Studies performed on isolated mouse liver mitochondria showed that both ZEN and T-2 toxin might act directly on mitochondria to induce a PTPC-dependent permeabilization of mitochondrial membranes. Moreover, they may target different members of PTPC. Indeed, although the inner membrane protein adenine nucleotide translocase could be the target of T-2 toxin, ZEN seems to target the outer membrane protein voltage-dependent anion channel. Cells pretreatment with the p53 inhibitor pifithrin-alpha suggested that ZEN but not T-2 toxin triggered a p53-dependent mitochondrial apoptotic pathway. Finally, mitochondrial alterations induced by ZEN and T-2 toxin are mediated by Bcl-2 family proteins, such as Bax, and prevented by Bcl-x(L) and to a lesser extent by Bcl-2. Taken together, these data indicate that mitochondria play a pivotal role in both ZEN- and T-2 toxin-induced apoptosis and that PTPC members and proteins of Bcl-2 family should be interesting targets to overcome fusarotoxin toxicity.

PMID: 19541794 [PubMed - indexed for MEDLINE]

27. Toxicology. 2009 Aug 3;262(2):153-61. Epub 2009 Jun 12.

Oxidative stress induction by T-2 toxin causes DNA damage and triggers apoptosis via caspase pathway in human cervical cancer cells.

Chaudhari M, Jayaraj R, Bhaskar AS, Lakshmana Rao PV.

Division of Pharmacology and Toxicology, Defence Research and Development Establishment, Jhansi Road, Gwalior 474002, India.

T-2 toxin is the most toxic trichothecene and both humans and animals suffer from several pathological conditions after consumption of foodstuffs contaminated with trichothecenes. We investigated the molecular mechanism of T-2 toxin induced cytotoxicity and cell death in HeLa cells. T-2 toxin at LC50 of 10 ng/ml caused time dependent increase in cytotoxicity as assessed by dye uptake, lactatedehydrogenase leakage and MTT assay. The toxin caused generation of reactive oxygen species as early as 30 min followed by significant depletion of glutathione levels and increased lipid peroxidation. The results indicate oxidative stress as underlying mechanism of cytotoxicity. Single stranded DNA damage after T-2 treatment was observed as early as 2 and 4h by DNA diffusion assay. The cells exhibited apoptotic morphology like condensed chromatin and nuclear fragmentation after 4h of treatment. Downstream of T-2 induced oxidative stress and DNA damage a time dependent increase in expression level of p53 protein was observed. The increase in Bax/Bcl2 ratio indicated shift in response, in favour of apoptotic process in T-2 toxin treated cells. Western blot analysis showed increase in levels of mitochondrial apoptogenic factors Bax, Bcl-2, cytochrome-c followed by activation of caspases-9, -3 and -7 leading to DNA fragmentation and apoptosis. In addition to caspase-dependent pathway, our results showed involvement of caspase-independent AIF pathway in T-2 induced apoptosis. Broad spectrum caspase inhibitor z-VAD-fmk could partially protect the cells from DNA damage but could not inhibit AIF induced oligonucleosomal DNA fragmentation beyond 4 h. Results of the study clearly show that oxidative stress is the underlying mechanism by which T-2 toxin causes DNA damage and apoptosis.

PMID: 19524637 [PubMed - indexed for MEDLINE]

28. Pol J Vet Sci. 2009;12(1):89-95.

Influence of low doses of deoxynivalenol on histopathology of selected organs of pigs.

Zielonka Ł, Wiśniewska M, Gajecka M, Obremski K, Gajecki M.

Division of Veterinary Prevention and Feed Hygiene, Department of Veterinary Public Health Protection, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, 10-718 Olsztyn, Poland.

Deoxynivalenol is one of mycotoxins that are most frequently determined in animal feed manufactured in Poland. The examination of histopathological lesions concomitant with deoxynivalenol intoxication is difficult because of the common, often synergistic, reaction of this mycotoxin with other toxins, such as zearalenone or ochratoxin A, which has a strong nephrotoxic activity. The possibility of estimating histopathological lesions in the course of intoxication with pure toxin at various doses is therefore of interest. Dosages used in this experiment relate to clinical cases observed in feeding the animals with whole ration feed obtained by processing feedingstuffs contaminated with Fusarium moulds. However, concerning the fact of one-shot administration of clinically pure toxin, the main question was if it was a sufficient dose to cause changes in the histopathological picture of gastrointestinal tract organs. The experiment was carried out on 12 nursery pigs of mixed breed (Polish White Large x Polish White Ear-pendent) with an average body weigh of 35 kg. The experimental nursery pigs were divided into 3 groups: group I (n=4)--control; group II (n=4)--DON administered at a dose of 0.2 mg/kg b.w.; group III (n=4)--DON administered at a dose of 0.4 mg/kg b.w. After slaughter of the animals, macroscopic examination was performed and segments of duodenum, jejunum, ileum, liver and mesenteric lymph nodes were sampled and assigned for histopathological examination. The results obtained equate to the clinically observed signs in swine production involving some nutrient metabolism disturbances in the gastrointestinal tract in the course of deoxynivalenol mycotoxicosis. Histopathological examination of segments of the duodenum, the jejunum, the ileum, the liver and the lymph nodes indicate that the regressive lesions are more expressed in the experimental group treated with the highest concentration of deoxynivalenol.

PMID: 19459445 [PubMed - indexed for MEDLINE]

29. Toxicology. 2009 Apr 28;258(2-3):106-15. Epub 2009 Jan 20.

Metabolism and cytotoxic effects of T-2 toxin and its metabolites on human cells in primary culture.

Königs M, Mulac D, Schwerdt G, Gekle M, Humpf HU.

Institute für Lebensmittelchemie, Westfälische Wilhelms-Universität Münster, Germany.

T-2 toxin belongs to the large group of trichothecene mycotoxins synthesized by various Fusarium molds which can infect raw agriculture materials. Among the trichothecenes, T-2 toxin is one of the most potent mycotoxins and poses a potential health risk in human nutrition. Several acute and chronic toxic effects were observed in humans after consumption of contaminated food. Due to the rapid metabolism of T-2 toxin by esterases, several metabolites can be found in food and also in vivo after ingestion. The aim of this work was to determine the effects of T-2 toxin and of several of its metabolites, namely HT-2 toxin, neosolaniol, T-2-triol and T-2 tetraol, on two human cells in primary culture: human renal proximal tubule epithelial cells (RPTEC) and normal human lung fibroblasts (NHLF). Concerning the cytotoxicity of T-2 toxin and its metabolites, different studies were performed with animal cells and cell lines but there are only little data about cytotoxic effects in human cells. The use of human cells in primary culture gives a good completion of the already known data because these might be limited due to the disadvantages of cell lines (e.g., immortalization, tumor derivation, longtime cultivation). In order to study the cytotoxicity and mode of cell death, the parameters cell viability, caspase-3-activity and LDH-release were measured after exposure to T-2 toxin and several of its metabolites. With IC(50) values of 0.2 and 0.5 microM T-2 toxin showed the strongest cytotoxic effect in both cells with triggering apoptosis as kind of cell death starting at a concentration of 100nM. The metabolites HT-2 toxin and neosolaniol revealed weaker cytotoxic effects (IC(50): 0.7-3.0 microM) and induced apoptosis at higher concentrations (>1 microM). The other metabolites were less cytotoxic (IC(50): 8.3-25.1 microM) and did not activate caspase-3. In addition to the analysis of cytotoxic effects, we also studied the metabolism of T-2 toxin in these cells in primary culture. Using LC-ESI-MS/MS we could demonstrate that both cells are able to transform T-2 toxin into HT-2 toxin. Further metabolic activity could only be observed in renal proximal tubule (RPTEC) cells by forming neosolaniol as a second metabolite.

PMID: 19428930 [PubMed - indexed for MEDLINE]

30. Mol Nutr Food Res. 2009 Apr;53(4):479-91.

Potential of deoxynivalenol to induce transcription factors in human hepatoma cells.

Nielsen C, Lippke H, Didier A, Dietrich R, Märtlbauer E.

Central Institute of the Bundeswehr Medical Service, Department of Food Chemistry and Environmental Chemistry, Garching-Hochbrück, Germany.

To assess the hepatotoxicity of deoxynivalenol (DON), human hepatoma cells (Hep-G2) were used as an in vitro model. After exposing Hep-G2 cells to low (1 mciroM) and high dose (10 mciroM), gene expression profiles were analysed by microarray. More than 5% of genes were up-regulated, most of them being involved in transcriptional regulation. By real-time RT-PCR, elevated expression of transcription factors, commonly induced by activation of MAPK-pathway, was demonstrated for Hep-G2 cells on mRNA and protein level. Further studies, involving U937 human monocytes, showed that effects of DON treatment on mRNA and protein level were concentration-dependent and cell-specific. An inverse relation was noticed for the level of DON induced expression of transcription factors (JUN, FOS, EGR1 and ATF3) and the susceptibility of the cell lines towards the mycotoxin. This is the first report giving evidence that on a molecular level the mild hepatotoxic effects of DON are probably caused by the induction of transcription factors which are known to be associated with injury-induced liver regeneration processes. With ATF3, a novel downstream target gene was identified in DON-related cell signalling suggesting a potential linkage between molecular action and biological effects like reduction of glycogen storage in liver tissue.

PMID: 19360757 [PubMed - indexed for MEDLINE]

31. Pol J Vet Sci. 2008;11(4):339-45.

Histological estimation of the small intestine wall after administration of feed containing deoxynivalenol, T-2 toxin and zearalenone in the pig.

Obremski K, Zielonka L, Gajecka M, Jakimiuk E, Bakuła T, Baranowski M, Gajecki M.

Division of Veterinary Prophylaxis and Feed Hygiene, Department of Veterinary Health Protection, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Oczapowskiego 13, 10-718 Olsztyn, Poland.

Fusarium spp. moulds are common in moderate climate regions of North America, Asia and Europe. They produce hepatotoxic and nephrotoxic mycotoxins, acting like estrogens, impairing hemopoesis and immunosuppressing. Actively dividing skin cells, lymphatic tissue, haemopoetic tissue and gastrointestinal tissue are the most sensitive for these trichothecenes action. The mucosal membrane of the gastrointestinal tract is the first barrier of the organism contacting with foreign antigens like feed proteins, natural toxins, saprophytic and pathogenic microflora and mycotoxins. The aim of this study was to perform histological estimation of the porcine small intestine after short term intoxication with low doses of deoxynivalenol (DON), T-2 toxin (T-2) and zearalenone (ZEA) obtained from wheat naturally contaminated with Fusarium moulds. Experimental pigs (n=5) were fed for 14 days feed containing DON, T-2 and ZEA (28.9, 11.5 and 33.2 microg kg(-1) of feed). On the last day of the experiment, the animals were euthanised and samples of the jejunum were collected for histological examination. In the experimental pigs, normally developed intestinal villi and crypts were found. However, number of acidophilic granulocytes in the mucous membrane and decreased numbers of goblet cells, increased numbers of endothelial lymphocytes and numerous plasma cells in intestinal epithelium was observed. On the surface of the intestinal epithelium the glycocalyx was poorly developed. The results obtained suggest that short term intoxication with low doses of DON, T-2 and ZEA does not cause significant changes in the histological structure of the small intestine in the pig. However, low concentrations of DON, T-2 and ZEA probably influence enterocytes metabolism and evoke inflammation of the mucous membrane of the small intestine.

PMID: 19227132 [PubMed - indexed for MEDLINE]

32. Toxicology. 2008 Dec 5;254(1-2):19-28. Epub 2008 Sep 10.

Different apoptotic pathways induced by zearalenone, T-2 toxin and ochratoxin A in human hepatoma cells.

Bouaziz C, Sharaf El Dein O, El Golli E, Abid-Essefi S, Brenner C, Lemaire C, Bacha H.

Laboratory of Research on Biologically Compatible Compounds, Faculty of Dentistry, Rue Avicenne, Monastir 5000, Tunisia.

Mycotoxins, secondary metabolites produced by moulds, have been shown to cause diverse toxic effects in animals and are also suspected of disease causation in humans. The present study compares the molecular mechanisms of the toxicity of zearalenone (ZEN), T-2 toxin and ochratoxin A (OTA) in human hepatoma cells HepG2. The three mycotoxins-induced a caspase-dependent mitochondrial apoptotic pathway. The mitochondrial alterations include: bax relocalisation into the mitochondrial outer membrane, loss of the mitochondrial transmembrane potential, PTPC opening, and cytochrome c (but not AIF) release. In the presence of ZEN and T-2 toxin, reactive oxygen species (ROS) level was highly increased at an early stage even before mitochondrial alterations were observed, whereas OTA-induced only O(2)(-) generation among total ROS. This ROS production appears as a consequence of mitochondrial alterations. HepG2 cell treatment with the p53 inhibitor pifithrin-alpha (PFT) and western blot analysis suggested that both ZEN and OTA, but not T-2 toxin, trigger a p53-dependent apoptotic pathway. These results clearly point to a central role of mitochondria in the apoptotic process induced by ZEN, T-2 toxin and OTA and provide new insights into the molecular mechanisms by which these mycotoxins might promote hepatotoxicty.

PMID: 18834919 [PubMed - indexed for MEDLINE]

33. Arch Anim Nutr. 2008 Aug;62(4):263-86.

Effects of a Fusarium toxin-contaminated triticale, either untreated or treated with sodium metabisulphite (Na2S2O5, SBS), on weaned piglets with a special focus on liver function as determined by the 13C-methacetin breath test.

Dänicke S, Beineke A, Goyarts T, Valenta H, Beyer M, Humpf HU.

Institute of Animal Nutrition, Friedrich-Loeffler-lnstitute (FLI), Federal Research Institute for Animal Health, Braunschweig, Germany.

The aim of the present experiment was to test the effects of a wet preservation of triticale contaminated mainly with deoxynivalenol (DON) with sodium metabisulphite (Na2S2O5, SBS) on growth performance, liver function, clinical-chemical plasma parameters and organ histopathology of piglets. For this purpose both the uncontaminated control triticale and the DON contaminated triticale were included in the piglet diet either untreated (CON, FUS) or SBS-treated (CON-SBS, FUS-SBS) and fed for 28 d starting from weaning. The dietary concentrations of DON and DON sulfonate (DONS), the DON derivative resulting from the SBS treatment, amounted to 0.156, 0.084, 2.312 and 0.275 mg DON per kg CON, CON-SBS, FUS and FUS-SBS diet, and to <0.05, <0.05, <0.05 and 1.841 mg/kg diet, respectively. Feeding the FUS diet significantly reduced the feed intake compared to the other three groups as indicated by the significant interactions between triticale source and SBS treatment when the whole experimental period of 28 d was considered (p = 0.014) while live weight gain and feed to gain ratio remained unaffected. The total plasma protein concentration was significantly depressed due to feeding the contaminated diets whereas SBS treatment exerted an increasing effect at the same time (45.4, 49.5, 40.7 and 46.5 g/l for piglets fed the CON, CON-SBS, FUS and FUS-SBS diet, respectively). The liver function was tested by the 13C-methacetin breath test (MBT) allowing evaluation of the cytochrome P4501A2 activity. MBT results, expressed as cumulative percentage dose recovery after 360 min (cPDR360) revealed a slight stimulation of liver function due to SBS treatment (p = 0.052) (37.5, 39.4, 37.4 and 55.1% for piglets fed the CON, CON-SBS, FUS and FUS-SBS diet, respectively). Liver weight and histopathological scoring were only weakly related to the MBT results. Further histopathological examinations of kidneys, pancreas and heart revealed no treatment effects. It was concluded that the SBS treatment of the contaminated triticale restored the performance of piglets to the level of the piglets fed the control diet while the effects on liver function, clinical-chemical plasma parameters - excepting the protein concentration - and organ histopathology were only marginal.

PMID: 18763622 [PubMed - indexed for MEDLINE]

34. Vet Res Commun. 2008 Sep;32 Suppl 1:S311-3.

Immune effects of four Fusarium-toxins (FB1, ZEA, NIV, DON) on the proliferation of Jurkat cells and porcine lymphocytes: in vitro study.

Severino L, Russo R, Luongo D, De Luna R, Ciarcia R, Rossi M.

Department of Pathology and Animal Health, University of Naples Federico II, Naples, Italy.

PMID: 18683067 [PubMed - indexed for MEDLINE]

35. J Appl Toxicol. 2009 Jan;29(1):7-14.

In vitro evaluation of the chemoprotective action mechanisms of leontopodic acid against aflatoxin B1 and deoxynivalenol-induced cell damage.

Costa S, Schwaiger S, Cervellati R, Stuppner H, Speroni E, Guerra MC.

Department of Pharmacology, University of Bologna, Via Irnerio 48, Bologna 40126, Italy.

Several in vitro studies showed that free radical scavengers possess chemopreventive properties against mycotoxin-induced cell damage which are at least partially associated with the induction of phase II detoxifying enzymes and antioxidant enzymes like glutathione S-transferase (GST) and glutathione peroxidase (GPx). The aim of this project was to study the chemopreventive effects of leontopodic acid (LA), a potent natural occurring free radical scavenger isolated from the aerial parts of Leontopodium alpinum. Different mycotoxins were evaluated in two different cell lines on the basis of their specific toxicity: aflatoxin B1 (AFB1) on HepG2 cells and deoxynivalenol (DON) on U937 cells. Cell viability and reactive oxygen species concentration were determined, and the effects of pre-treatment with LA on these parameters were investigated together with the GST and GPx activity as well as the concentration of reduced glutathione. The results show that LA protects U937 cells from DON-induced cell damage but not HepG2 cells from AFB1. Moreover LA is able to enhance GPx activity in U937, but not GST activity in HepG2. We hypothesize that the increase in detoxifying enzymes is probably the main mechanism of antioxidant mediated chemoprevention.

Copyright (c) 2008 John Wiley & Sons, Ltd.

PMID: 18636399 [PubMed - indexed for MEDLINE]

36. Toxicon. 2008 Jul;52(1):156-62. Epub 2008 May 29.

Effects of four Fusarium toxins (fumonisin B(1), alpha-zearalenol, nivalenol and deoxynivalenol) on porcine whole-blood cellular proliferation.

Luongo D, De Luna R, Russo R, Severino L.

Department of Pathology and Animal Health, University of Naples Federico II, via F. Delpino 1, 80137 Naples, Italy.

The in vitro effects of four Fusarium toxins, fumonisin B(1) (FB(1)), alpha-zearalenol (alpha-ZEA), nivalenol (NIV) and deoxynivalenol (DON), on mitogen-induced cell proliferation were determined in swine whole-blood cultures. Considering the lack of sufficient toxicological data both on single and in combination effects, in vitro studies may contribute to risk assessment of these toxins. Incubation with increasing concentrations of FB(1) did not produce any consequence on proliferation; in contrast alpha-ZEA, NIV and DON showed an inhibitory effect. Dose-response curves for each mycotoxin were generated. NIV was found to be the most potent toxin followed by DON and alpha-ZEA. The effects of both FB(1)+alpha-ZEA and NIV+DON mixtures were also analysed to investigate possible interactions. The results indicated that combination of FB(1)+alpha-ZEA produces a synergistic inhibition of porcine cell proliferation; whereas there is no interaction between DON and NIV on porcine whole-blood proliferation, at tested concentrations.

PMID: 18620720 [PubMed - indexed for MEDLINE]

37. Toxicol Lett. 2008 Jul 10;179(3):113-7. Epub 2008 May 8.

The effect of feeding a diet naturally contaminated with deoxynivalenol (DON) and zearalenone (ZON) on the spleen and liver of sow and fetus from day 35 to 70 of gestation.

Tiemann U, Brüssow KP, Dannenberger D, Jonas L, Pöhland R, Jäger K, Dänicke S, Hagemann E.

Unit of Reproductive Biology, FBN Research Institute for the Biology of Farm Animals, Wilhelm Stahl-Allee 2, Dummerstorf, Germany.

Pregnant sows were fed a control diet (CON, 0.15 mg deoxynivalenol (DON) and 0.0035 mg zearalenone (ZON) per kg diet) or diet containing 15% of Fusarium toxin contaminated triticale (MYCO, 4.42 mg DON and 0.048 mg ZON per kg diet) during days 35-70 of gestation. All sows were fed in a restricted feeding regimen with the same amount of feed (2000 g/d) over the whole study. At the end of the experiment, fetuses were delivered by Caesarian section and samples of spleen and liver of euthanized sows and fetuses were analyzed. At terminal necropsy, no macroscopic lesion was observed in any organ of either sows or fetuses. The histopathological data indicated significant alteration only in elevated iron staining in the red pulp of spleens in sows of MYCO group after 35 days of feeding. The presence of hemosiderin particles in the spleen sections was confirmed by transmission electron microscopical investigation and by an enhanced Fe2+ concentration in spleen. A glycogen increase (p<0.05) was found in liver cells of fetuses in the experimental group. Together, the results provide evidence of spleen dysfunction (hemosiderosis) in sows fed a Fusarium toxin-contaminated wheat, however, with absence of clinical signs. Enhanced glycogen and an impairment of mitochondria in liver of fetuses was present when their mothers consumed the MYCO diet.

PMID: 18550300 [PubMed - indexed for MEDLINE]

38. Toxicol Appl Pharmacol. 2008 Apr 1;228(1):84-92. Epub 2007 Nov 22.

Both direct and indirect effects account for the pro-inflammatory activity of enteropathogenic mycotoxins on the human intestinal epithelium: stimulation of interleukin-8 secretion, potentiation of interleukin-1beta effect and increase in the transepithelial passage of commensal bacteria.

Maresca M, Yahi N, Younès-Sakr L, Boyron M, Caporiccio B, Fantini J.

Laboratoire des Interactions Moléculaires et Systèmes Membranaires (IMSM), Université Paul Cézanne, Faculté des Sciences et Techniques de Saint-Jérôme, Avenue Escadrille Normandie-Niemen, 13397, Marseille Cedex 20, France.

Mycotoxins are fungal secondary metabolites responsible of food-mediated intoxication in animals and humans. Deoxynivalenol, ochratoxin A and patulin are the best known enteropathogenic mycotoxins able to alter intestinal functions resulting in malnutrition, diarrhea, vomiting and intestinal inflammation in vivo. Although their effects on intestinal barrier and transport activities have been extensively characterized, the mechanisms responsible for their pro-inflammatory effect are still poorly understood. Here we investigated if mycotoxin-induced intestinal inflammation results from a direct and/or indirect pro-inflammatory activity of these mycotoxins on human intestinal epithelial cells, using differentiated Caco-2 cells as model and interleukin 8 (IL-8) as an indicator of intestinal inflammation. Deoxynivalenol was the only mycotoxin able to directly increase IL-8 secretion (10- to 15-fold increase). We also investigated if these mycotoxins could indirectly stimulate IL-8 secretion through: (i) a modulation of the action of pro-inflammatory molecules such as the interleukin-1beta (IL-1beta), and/or (ii) an increase in the transepithelial passage of non-invasive commensal Escherichia coli. We found that deoxynivalenol, ochratoxin A and patulin all potentiated the effect of IL-1beta on IL-8 secretion (ranging from 35% to 138% increase) and increased the transepithelial passage of commensal bacteria (ranging from 12- to 1544-fold increase). In addition to potentially exacerbate established intestinal inflammation, these mycotoxins may thus participate in the induction of sepsis and intestinal inflammation in vivo. Taken together, our results suggest that the pro-inflammatory activity of enteropathogenic mycotoxins is mediated by both direct and indirect effects.

PMID: 18308354 [PubMed - indexed for MEDLINE]

39. J Appl Toxicol. 2008 Aug;28(6):765-72.

Rat liver clone-9 cells in culture as a model for screening hepatotoxic potential of food-related products: hepatotoxicity of deoxynivalenol.

Sahu SC, Garthoff LH, Robl MG, Chirtel SJ, Ruggles DI, Flynn TJ, Sobotka TJ.

Division of Toxicology, Center for Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708, USA.

Deoxynivalenol (DON) is a mycotoxin food contaminant found in several cereal grains. The literature on the liver toxicity of DON in vivo is conflicting and does not clearly characterize its hepatotoxic effects. Cultured rat liver clone-9 cells were used as a model to assess the hepatotoxic potential of DON. The cell cultures, seeded onto 96-well plates, were treated at confluence with varying concentrations of DON (0-100 microg ml(-1)) for 48 h at 37 degrees C in 5% CO2. After the treatment period, the cells were assayed for a number of hepatotoxic endpoints that included cytotoxicity, double-stranded DNA (ds-DNA) content, oxidative stress and mitochondrial function. The concentration-dependent toxicity of DON, as measured by cytotoxicity and ds-DNA content, was observed over the entire concentration range studied beginning at 0.5 microg ml(-1). DON also induced a significant concentration-dependent increase in oxidative stress at DON concentrations starting at 10 microg ml(-1). The mitochondrial function of the treated cells decreased with the increasing concentration of DON exposure, but it was not statistically different from that of the control value. Liver histopathology observed at 3, 24 and 72 h following a single intraperitoneal administration dose of DON (10 mg kg(-1) BW) to adult male rats is consistent with early mild hepatotoxicity. The overall results of this study suggest that acute DON exposure has early mild cytotoxic effects on hepatocytes in vivo that are expressed as severe effects in rat liver clone-9 cells in vitro.

PMID: 18300328 [PubMed - indexed for MEDLINE]

40. Biol Pharm Bull. 2007 Sep;30(9):1808-12.

Toxic alterations in chick embryonic liver and spleen by acute exposure to Fusarium-producing mycotoxin deoxynivalenol.

Moon Y, Kim HK, Suh H, Chung DH.

Department of Microbiology and Immunology, Medical Research Institute, Pusan National University School of Medicine, Busan 602-739, Korea.

Food mycotoxin deoxynivalenol (vomitoxin, DON) produced by Fusarium graminearum and F. culmorum can induce rapid diminution of lymphoid tissues and lymphopenia in the growing chickens and mammals. We first investigated the direct acute effects of DON on the chick immune-related embryo tissues such as embryonic liver and spleen. Direct DON administration into the embryonic eggs caused toxin accumulation in liver in a time-dependent manner. Electron microscopic observation showed a notable accumulation of fat droplet in the liver tissue and the re-exposed hatched chicken showed more distinguishing enlarged fat globules, so-called fatty cysts like human steatosis. Regarding effects of deoxynivalenol on the chick embryonic spleen, fatty change was also observed in splenocytes. Functionally, mitogen-stimulated cellular and humoral lympho-proliferations were suppressed in the DON-treated embryo. Conclusively, acute direct exposure to deoxynivalenol in the chick embryo caused toxic histological alterations in the liver and spleen and suppressed in vitro lymphoblastogenesis.

PMID: 17827746 [PubMed - indexed for MEDLINE]

41. Toxicology. 2007 Oct 30;240(1-2):48-59. Epub 2007 Aug 1.

Cytotoxicity, metabolism and cellular uptake of the mycotoxin deoxynivalenol in human proximal tubule cells and lung fibroblasts in primary culture.

Königs M, Lenczyk M, Schwerdt G, Holzinger H, Gekle M, Humpf HU.

Institut für Lebensmittelchemie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 45, 48149 Münster, Germany.

At the level of the whole animal, the toxic effects of the mycotoxin deoxynivalenol (DON) range from causing diarrhoea, vomiting, gastro-intestinal inflammation to necrosis of several tissues. It also affects the immune system and leads to kidney lesions. Although DON has been tested in different human and animal cell lines for its cytotoxicity, these tests might be limited due to the disadvantages of cell lines (e.g. immortalization, tumour derivation, longtime cultivation) and do not necessarily reflect the response of normal cells. In order to overcome this problem and to be closer to the human situation, we studied the effect of DON in human kidney epithelial cells (renal proximal tubule epithelial cells, RPTEC) and human lung fibroblasts (normal human lung fibroblast, NHLF) in primary culture. Cell viability, apoptotic and necrotic cell death, collagens I, III and IV as well as fibronectin secretion were determined. It could be demonstrated that DON has a distinct cytotoxic effect on human primary cells. A reduction in viability can be observed in both cell types, with fibroblasts reacting more sensitive. Furthermore, DON caused mainly necrotic cell death in kidney cells whereas mainly apoptotic cell death in fibroblasts. DON had no effect on collagen secretion in RPTEC cells. Collagen secretion was partially decreased in NHLF. In both cells, fibronectin secretion was reduced after 5 days of exposure. We also studied the metabolism and the cellular uptake of DON using LC-MS/MS. DON was neither metabolized by proximal tubule cells nor by fibroblasts. DON is incorporated into the cells whereas the intracellular amount of DON in kidney cells is higher than in fibroblasts. No accumulation of DON occurred in the cells.

PMID: 17825972 [PubMed - indexed for MEDLINE]

42. Food Chem Toxicol. 2008 Jan;46(1):125-35. Epub 2007 Jul 18.

A 90-day subchronic toxicity study of nivalenol, a trichothecene mycotoxin, in F344 rats.

Takahashi M, Shibutani M, Sugita-Konishi Y, Aihara M, Inoue K, Woo GH, Fujimoto H, Hirose M.

Division of Pathology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan.

A subchronic toxicity study of nivalenol (NIV), a trichothecene mycotoxin, was conducted in male and female F344 rats fed diet containing 0, 6.25, 25 or 100 ppm concentration for 90 days. Decrease of body weight and loose stools were observed at 100 ppm in both sexes from the start of the experiment, and body weight reduction was also observed at 25 ppm in males from week 6. At necropsy, many organs demonstrated reduced absolute weights at 100 ppm in both sexes, mostly due to the reduction in the body growth, with reduction of relative thymus weight also being evident in females. Hematologically, decrease of the white blood cell count was found at 100 ppm in males and from 6.25 ppm in females. In addition, decreased platelet counts in both sexes, red blood cell counts in males, and the hemoglobin concentration in females were detected at 100 ppm. Histopathologically, treatment-related changes were predominantly observed in the hematopoietic and immune organs and the anterior pituitary in both sexes and female reproductive organs at 100 ppm, such as thymic atrophy, hypocellularity in the bone marrow, diffuse hypertrophy of basophilic cells with increase of castration cells in the anterior pituitary, and increase of ovarian atretic follicles. Based on the hematological data, the no-observed-adverse-effect level of NIV was determined to be less than 6.25 ppm (0.4 mg/kg body weight/day for both males and females).

PMID: 17765382 [PubMed - indexed for MEDLINE]

43. Ann Agric Environ Med. 2007;14(1):103-7.

Fusarium mycotoxins in Lithuanian cereals from the 2004-2005 harvests.

Mankeviciene A, Butkute B, Dabkevicius Z, Suproniene S.

Department of Plant Pathology and Protection, Lithuanian Institute of Agriculture, LT-58344 Akademija, Kedainiai district, Lithuania.

Fusarium mycotoxins deoxynivalenol (DON), T-2 toxin, and zearalenone (ZEN) contamination in 5 kinds of cereal grain harvested in 2004 and 2005 in different regions of Lithuania was examined for their occurrence frequency and level. In all cereal species DON was the most frequently detected mycotoxin with an incidence rate of 98.0-100% and range in positive samples from traces to 691 microg kg(-1) in 2004 and 62.5-94.0%, range from traces to 1,121 microg kg(-1) in 2005, respectively. All the tested oat samples collected in 2004-2005 were found to be contaminated with the T-2 toxin. In one sample from the year 2004 the level of T-2 toxin (121.5 microg kg(-1)) exceeded the allowable level. In 2004, ZEN contamination was more frequent in spring wheat, barley and oats grain, whereas in 2005 this toxin was identified at higher levels only in barley grain (68.0%). In one barley grain sample from 2004, ZEN content (193.4 microg kg(-1)) exceeded the allowable level. Variation in the relative air-humidity exerted some effect on the incidence of Fusarium spp. fungi and mycotoxin content in wheat grain. The weather conditions at harvesting contributed to an increase in the contents of Fusarium fungi and DON and ZEN mycotoxins produced by them in winter wheat grain. This risk factor increases the threat to human and animal health.

PMID: 17655186 [PubMed - indexed for MEDLINE]

44. Mycopathologia. 2007 Oct;164(4):171-81. Epub 2007 Jul 3.

The role of fungal proteinases in pathophysiology of Stachybotrys chartarum.

Yike I, Rand T, Dearborn DG.

Mary Ann Swetland Center for Environmental Health, Case Western Reserve University, Cleveland, OH 44106, USA.

The adverse health effects of Stachybotrys chartarum have often been linked to exposure to the trichothecene mycotoxins. Recent studies have shown that in addition to mycotoxins this fungus is capable of producing and secreting in vivo proteins such as hemolysins and proteinases. Spore extracts obtained from a high trichothecene producing isolate JS 58-17 exhibited a significantly lower proteolytic activity compared to the low trichothecene producer, JS 58-06. Growing isolates on rice or potato dextrose agar results in higher proteolytic activity of the spores compared to those grown on drywall. Proteinases in the spore extracts can hydrolyze gelatin and collagen I and IV. Analysis of zymograms shows the presence of several proteins with proteolytic activity in the spores of S. chartarum. Human tracheal epithelial cells exposed to spore extracts produced significantly higher levels of IL-6, IL-8, and TNF-alpha than control cells. This stimulation of cytokine production was completely abolished by Pefabloc, a serine protease inhibitor. Neutrophil numbers and proinflammatory cytokine (IL1-beta and TNF-alpha) concentrations were highly elevated in the lungs of 7 day old rat pups exposed intratracheally to 4 x 10(4) spores/gm body weight compared to control. No significant differences in those inflammatory indices in vivo were noted between the treatments with the high trichothecene producer, isolate JS 58-17 and JS 58-06, which does not produce macrocyclic trichothecenes. Immunohistochemistry revealed reduced collagen IV labeling in spore-induced lung granulomas in rat pups exposed to both isolates. These results suggest that proteinases from S. chartarum spores significantly contribute to lung inflammation and injury.

PMID: 17610048 [PubMed - indexed for MEDLINE]

45. Vet Res. 2007 Jul-Aug;38(4):635-46. Epub 2007 Jun 13.

Effect of subacute oral doses of nivalenol on immune and metabolic defence systems in mice.

Gouze ME, Laffitte J, Pinton P, Dedieux G, Galinier A, Thouvenot JP, Loiseau N, Oswald IP, Galtier P.

Laboratoire de Pharmacologie-Toxicologie, UR66, INRA, 180 Chemin de Tournefeuille, 31931 Toulouse, France.

Nivalenol (NIV) is a toxic Fusarium secondary trichothecene metabolite occurring naturally in cereal grains. In order to evaluate the no observed adverse effect level (NOAEL), we tested the effects of a large array of oral doses of this toxin for responses on plasma biochemistry, the immune system and hepatic drug metabolism in mice. C57Bl6 mice received oral doses of toxin (0.014, 0.071, 0.355, 1.774 or 8.87 mg/kg bw) 3 days a week for 4 weeks. Only the highest dose of NIV induced an increase in plasma phosphate, decreases in plasma urea and immunoglobulin M and additional changes like increases in plasma alkaline phosphatase and immunoglobulin G. Interleukin 4 production was increased in cultured murine splenocytes. Regarding liver drug metabolising enzymes, the only glutathione transferase activity accepting 1-chloro-2,4-dinitro-benzene as substrate was transiently increased in mice receiving low doses (0.071 and 0.355 mg/kg bw) of NIV. Regarding the cytochrome P450 monooxygenases, no significant change was observed in ethoxyresorufin O-deethylase activity whereas both methoxyresorufin and pentoxyresorufin O-dealkylase activities were decreased by 38-45% for the highest dose (8.87 mg/kg bw) of NIV. However, when analysed by Western blot analysis, the protein expression of mouse P450 1a, 2b, 2c, 3a and 4a subfamilies was unchanged in animals receiving NIV. In conclusion, the NOAEL of this toxin in our study was 1.774 mg/kg bw, corresponding to an exposure to 5 ppm contaminated food. Indeed hepatotoxicity appears in the only mice treated with a five fold higher oral dose of 8.87 mg/kg bw of NIV. Such exposure levels appear to be by far higher than the maximal natural occurrence measured in European cereals, known to range from 0.34 to 1.86 ppm.

PMID: 17565910 [PubMed - indexed for MEDLINE]

46. Toxicol Appl Pharmacol. 2007 Jul 15;222(2):190-201. Epub 2007 May 8.

Cytotoxicity of diacetoxyscirpenol is associated with apoptosis by activation of caspase-8 and interruption of cell cycle progression by down-regulation of cdk4 and cyclin B1 in human Jurkat T cells.

Jun DY, Kim JS, Park HS, Song WS, Bae YS, Kim YH.

Laboratory of Immunobiology, School of Life Sciences and Biotechnology, College of Natural Sciences, Kyungpook National University, Daegu 702-701, Republic of Korea.

To understand the mechanism underlying T-cell toxicity of diacetoxyscirpenol (DAS) from Fusarium sambucinum, its apoptogenic as well as growth retardation activity was investigated in human Jurkat T cells. Exposure to DAS (0.01-0.15 microM) caused apoptotic DNA fragmentation along with caspase-8 activation, Bid cleavage, mitochondrial cytochrome c release, activation of caspase-9 and caspase-3, and PARP degradation, without any alteration in the levels of Fas or FasL. Under these conditions, necrosis was not accompanied. The cytotoxicity of DAS was not blocked by the anti-Fas neutralizing antibody ZB-4. Although the DAS-induced apoptotic events were completely prevented by overexpression of Bcl-xL, the cells overexpressing Bcl-xL were unable to divide in the presence of DAS, resulting from the failure of cell cycle progression possibly due to down-regulation in the protein levels of cdk4 and cyclin B1. The DAS-mediated apoptosis and activation of caspase-8, -9, and -3 were abrogated by either pan-caspase inhibitor (z-VAD-fmk) or caspase-8 inhibitor (z-IETD-fmk). While the DAS-mediated apoptosis and activation of caspase-9 and caspase-3 were slightly suppressed by the mitochondrial permeability transition pore inhibitor (CsA), both caspase-8 activation and Bid cleavage were not affected by CsA. The activated normal peripheral T cells possessed a similar susceptibility to the cytotoxicity of DAS. These results demonstrate that the T-cell toxicity of DAS is attributable to not only apoptosis initiated by caspase-8 activation and subsequent mitochondrion-dependent or -independent activation of caspase cascades, which can be regulated by Bcl-xL, but also interruption of cell cycle progression caused by down-regulation of cdk4 and cyclin B1 proteins.

PMID: 17559898 [PubMed - indexed for MEDLINE]

47. Toxicol Sci. 2007 Aug;98(2):526-41. Epub 2007 May 4.

Neurotoxicity and inflammation in the nasal airways of mice exposed to the macrocyclic trichothecene mycotoxin roridin a: kinetics and potentiation by bacterial lipopolysaccharide coexposure.

Islam Z, Amuzie CJ, Harkema JR, Pestka JJ.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing, Michigan 48824, USA.

Macrocyclic trichothecene mycotoxins produced by indoor air molds potentially contribute to symptoms associated with damp building illnesses. The purpose of this investigation was to determine (1) the kinetics of nasal inflammation and neurotoxicity after a single intranasal instillation of roridin A (RA), a representative macrocyclic trichothecene; and (2) the capacity of lipopolysaccharide (LPS) to modulate RA's effects. C57Bl/6 female mice were intranasally instilled once with 50 mul of RA (500 mug/kg body weight [bw]) in saline or saline only and then nose and brain tissues were collected over 72 h and processed for histopathologic and messenger RNA (mRNA) analysis. RA-induced apoptosis specifically in olfactory sensory neurons (OSNs) after 24 h postinstillation (PI) causing marked atrophy of olfactory epithelium (OE) that was maximal at 72 h PI. Concurrently, there was marked bilateral atrophy of olfactory nerve layer of the olfactory bulbs (OBs) of the brain. In the ethmoid turbinates, upregulated messenger RNA (mRNA) expression of the proapoptotic gene FAS and the proinflammatory cytokines tumor necrosis factor-alpha, interleukin (IL)-6, IL-1, and macrophage inhibitory protein-2 was observed from 6 to 24 h PI, whereas expression of several other proapoptotic genes (PKR, p53, Bax, and caspase-activated DNAse) was detectable only at 24 h PI. Simultaneous exposure to LPS (500 ng/kg bw) and a lower dose of RA (250 mug/kg bw) magnified RA-induced proinflammatory gene expression, apoptosis, and inflammation in the nasal tract. Taken together, the results suggest that RA markedly induced FAS and proinflammatory cytokine expression prior to evoking OSN apoptosis and OE atrophy and that RA's effects were augmented by LPS.

PMID: 17483119 [PubMed - indexed for MEDLINE]

48. Food Addit Contam. 2007 Mar;24(3):306-14.

In vivo and in vitro effects of the mycotoxins zearalenone and deoxynivalenol on different non-reproductive and reproductive organs in female pigs: a review.

Tiemann U, Dänicke S.

Research Institute for the Biology of Farm Animals, Wilhelm Stahl-Allee 2, D-18196 Dummerstorf, Germany.

This review summarizes the toxicological data on the effects of the mycotoxins zearalenone (ZON), its metabolites, and deoxynivalenol (DON) on different parameters relating to reproductive and non-reproductive organs in female pigs. In vivo, 22 mg ZON kg(-1) in the diet cause alterations in the reproductive tract of swine such as in the uterus, and affects follicular and embryo development. ZON and its metabolites have been shown to bind competitively to oestrogen receptors in an in vitro system. The feeding of pigs with a 9 mg DON kg(-1)-contaminated diet can act on protein synthesis, humoral and cellular immune response depending on dose, exposure and timing of functional immune assay, and affect liver and spleen cell structures. Beside these effects, reproductive alterations were observed in pigs, too. Both in vivo and in vitro exposure to DON decreased oocyte and embryo development. In vitro application of DON to uterine cells inhibits their proliferation rate and modulates the process of translation at a different molecular level when compared with the in vivo application. The histopathological results provide evidence of spleen and liver dysfunction in the absence of clinical signs, especially in pigs fed higher concentrations of Fusarium toxin-contaminated wheat. Prepuberal gilts react more sensitively to DON > ZON feeding compared with pregnant sows. In the liver, histopathological changes such as glycogen decrease and interlobular collagen uptake were only observed in prepuberal gilts, whereas enhancement of haemosiderin was found in both perpuberal gilts and pregnant sows. This review presents some of the current knowledge on the biological activities of ZON and DON in pig. Altogether, ZON affects reproduction of pigs most seriously because it possesses oestrogenic activity. However, DON affects reproduction in pigs via indirect effects such as reduced feed intake, resulting in reduced growth or impairment of function in vital organs such as liver and spleen.

PMID: 17364934 [PubMed - indexed for MEDLINE]

49. Ann Agric Environ Med. 2006;13(2):259-62.

Pulmonary cytotoxicity of secondary metabolites of Stachybotrys chartarum (Ehrenb.) Hughes.

Pieckova E, Hurbankova M, Cerna S, Pivovarova Z, Kovacikova Z.

Slovak Medical University, Limbova 12, SK-83303 Bratislava, Slovakia.

Damp dwellings represent suitable conditions for extended indoor moulds. A cellulolytic micromycete Stachybotrys chartarum (Ehrenb.) Hughes is considered to be a tertiary colonizer of surfaces in affected buildings. Known adverse health effects of S. chartarum result from its toxins--trichothecenes or atranones, as well as spirolactams. Mechanism of their potential pathological effects on the respiratory tract has not yet been sufficiently clarified. The cytotoxic effects of complex chloroform-extractable endo- (in biomass) and exometabolites (in cultivation medium) of an indoor S. chartarum isolate of an atranone chemotype, grown on a liquid medium with yeast extract and sucrose at 25 degrees C for 14 d, on lung tissue were evaluated in the 3-day experiment. For the purpose, 4 mg of toxicants were intratracheally instilled in 200 g Wistar male rats. A trichothecene mycotoxin diacetoxyscirpenol was used as the positive control. Bronchoalveolar lavage (BAL) parameters--viability and phagocytic activity of alveolar macrophages (AM), activity of lactate dehydrogenase, acid phosphatase and cathepsin D in cell-free BAL fluid (BALF), as well as in BAL cells, were measured. Acute exposure to the metabolites caused statistically significant changes, indicating lung tissue injury in the experimental animals. Decreased AM viability and increased activity of lysosomal enzyme cathepsin D in BAL cells after fungal exometabolite exposure were the most impressive. As toxic principles were found predominantly in the growth medium, toxins were more likely responsible for lung cell damage than e.g. fungal cell wall components. S. chartarum toxic metabolites can contribute to the ill health of occupants of mouldy building after inhalation of contaminated aerosol.

PMID: 17195998 [PubMed - indexed for MEDLINE]

50. Cytokine. 2006 Oct;36(1-2):75-82. Epub 2006 Dec 12.

Mycotoxins nivalenol and deoxynivalenol differentially modulate cytokine mRNA expression in Jurkat T cells.

Severino L, Luongo D, Bergamo P, Lucisano A, Rossi M.

Department of Pathology and Animal Health, Division of Toxicology, University of Naples Federico II, via Delpino 1, 80137 Naples, Italy.

Deoxynivalenol (DON) and its hydroxylated form nivalenol (NIV) are Fusarium mycotoxins that occur in cereal grains alone or in combination. Several studies have shown that these metabolites affect lymphocyte functions. However, the molecular mechanisms underlying their activities are still partially known. To address this issue, we examined the influence of NIV and DON in modulating IFNgamma, IL-2 and IL-8 mRNA levels in Jurkat T cells. In PMA/ionomycin stimulated cells, pre-incubated with increasing concentrations of NIV, transcription was induced in the range 0.06-2 microM; higher concentrations of NIV were found non-stimulating (4 microM) or inhibitory (8 microM) for IFNgamma and IL-2 whereas IL-8 was still induced. DON administration elicited a similar profile for IL-8 and IFNgamma, whilst IL-2 mRNA was induced in a broader range of concentrations. Combination of NIV and DON at 1:1 and 1:10 ratios essentially restored the cytokine transcriptional pattern observed with NIV alone but the level of transcripts, with the exception of IL-8, peaked at lower concentrations suggesting interactive effects. Moreover both mycotoxins caused inhibition of cell proliferation, mediated by induction of apoptosis, confirming previous results and highlighting the usefulness of Jurkat as a T-cell model to study the effects of mycotoxins on the immune functions in humans.

PMID: 17166736 [PubMed - indexed for MEDLINE]

51. Zhonghua Yu Fang Yi Xue Za Zhi. 2006 Sep;40(5):314-8.

[Effects of vitamin C on the inhibition of human leucocyte antigen class I (HLA-I) expression of human peripheral blood mononuclear cells induced by deoxynivalenol in vitro].

[Article in Chinese]

Zhou BJ, Li YH, Zhang XH, Xing LX, Yan X, Wang JL, Liu J, Xing X.

Laboratory of Pathology, Hebei Medcial University, Shijiazhuang 050017, China.

OBJECTIVE: To explore the putative effects of Vitamin C (Vit C) on inhibition of human leucocyte antigen class I (HLA-I) expression of human peripheral blood mononuclear cells (HPBMCs) induced by deoxynivalenol (DON) in vitro. METHODS: The effects of Vit C on the changes of HLA-I expression of HPBMCs induced by DON in vitro were evaluated with cell culture, flow cytometry (FCM), Western blotting and immunocytochemical methods. RESULTS: FCM analysis showed that HLA-I expression of HPBMCs in DON treated cells was significantly lower than that in controls (FI 0.88 +/- 0.02 vs 1.00 +/- 0.03, P < 0.05). As compared with DON group, the HLA-I expressions of HPBMCs in the two Vit C (25 micromol/L and 100 micromol/L) pretreatment groups were all significantly increased (1.15 +/- 0.06 and 1.10 +/- 0.02 vs 0.88 +/- 0.02, P < 0.05). Exposure to different dosage of Vit C alone could dramatically increase the expression of HLA-I of HPBMCs in vitro as compared with that in the normal control (FI for 25 micromol/L and 100 micromol/L Vit C treatment group was 1.28 +/- 0.03 and 1.25 +/- 0.05 respectively, P < 0.05). Immunocytochemical results showed that the percentages of HLA-I positive expression of HPBMCs in Vit C pretreatment groups at different dosages were significantly higher than those in DON group (70.10 +/- 6.90)%, (64.50 +/- 5.50)% vs (42.20 +/- 4.30)%, P < 0.05. Western blotting confirmed the results of FCM and immunocytochemistry. CONCLUSIONS: Vitamin C pretreatment at different dosages could reverse at some extent the inhibitive effects of DON on HLA-I expression of HPBMCs.

PMID: 17166420 [PubMed - indexed for MEDLINE]

52. Zhonghua Yu Fang Yi Xue Za Zhi. 2006 Sep;40(5):309-13.

[Effects of vitamin C on apoptosis and proliferation inhibition of human peripheral blood mononuclear cells induced by deoxynivalenol in vitro].

[Article in Chinese]

Zhou BJ, Li YH, Zhang XH, Xing LX, Yan X, Wang JL, Liu J, Xing X.

Laboratory of Pathology, Hebei Medical University, Shijiazhuang 050017, China.

OBJECTIVE: To explore the effects of Vitamin C (Vit C) on the apoptosis and proliferation inhibition of human peripheral blood mononuclear cells (HPBMCs) induced by deoxynivalenol (DON) in vitro. METHODS: The effects of Vit C pretreatment at different dosages (25 micromol/L and 100 micromol/L) on apoptosis, apoptosis related genes expression and proliferation inhibition of HPBMCs induced by DON were evaluated with cell culture, flow cytometric DNA analysis and Western blotting. RESULTS: Flow cytometry (FCM) analysis showed that the apoptosis rate of HPBMCs in 2000 microg/L DON group was (28.82 +/- 1.67)%, which was significantly higher than that in control group (14.07 +/- 0.70, P < 0.05). Compared with DON group, the apoptosis rate of HPBMCs in 25 micromol/L Vit C pretreatment group was significantly decreased (28.82 +/- 1.67)% vs (22.39 +/- 1.05)%, P < 0.05, while that in 100 micromol/L Vit C pretreatment group was obviously increased (36.07 +/- 2.92)%, P < 0.05. Western blotting analysis showed that the expression of Bax and Caspase-3 up-regulated by DON was markedly decreased, while the expression of Bcl-2 down-regulated by DON was increased by 25 micromol/L Vit C pretreatment (P < 0.05). 100 micromol/L Vit C pretreatment could further increase the expression of Bax and Caspase-3 of HPBMCs induced by DON, while no significant effects on the Bcl-2 expression induced by DON were seen. FCM analysis showed that the proliferation index of HPBMCs in Vit C pretreatment groups at different dosages was all dramatically increased as compared with that in DON groups (P < 0.05). CONCLUSION: 25 micromol/L Vit C pretreatment could at certain extent inhibit the apoptosis and reverse the abnormal expression of apoptosis related genes of HPBMCs induced by DON in vitro, while 100 micromol/L Vit C pretreatment could further increase the apoptosis rate of HPBMCs induced by DON. Vit C pretreatment could reverse the proliferation inhibition of HPBMCs induced by DON in vitro.

PMID: 17166419 [PubMed - indexed for MEDLINE]

53. Toxicol In Vitro. 2007 Apr;21(3):457-65. Epub 2006 Nov 6.

Genotoxic potential associated with low levels of the Fusarium mycotoxins nivalenol and fusarenon X in a human intestinal cell line.

Bony S, Olivier-Loiseau L, Carcelen M, Devaux A.

UMR INRA-DGER Mycotoxines et Toxicologie Comparée des Xénobiotiques, Ecole Nationale Vétérinaire de Lyon, 1, av. Bourgelat, F-69280 Marcy l'Etoile, France.

This study aims to assess the genotoxic potential of nivalenol (NIV) and fusarenon X (FusX), produced by various Fusarium on cereals. Toxins were applied in time and dose-dependent experiments to the human enterocyte-like Caco-2 cell-line, both in dividing (undifferentiated) and in 10-12 days post-confluent cells (differentiated). Genotoxicity was evaluated through the alkaline Comet assay in a concentration range defined for each toxin as below the cytotoxicity threshold IC(10), determined by the MTS and the neutral red assays, to prevent false positive results because of DNA damage stemming from necrosis. Thus, genotoxicity was explored in the sub-cytotoxic 0-0.5 microM and 0-0.05 microM ranges respectively for NIV and FusX as the latter was found about 10-fold more cytotoxic than NIV. For both toxins, a 3h exposure did not cause any DNA damage, unlike after 24 and 72 h exposure in post confluent Caco-2 cells where DNA damage was significantly observed with a dose-dependent relationship. In dividing cells, only FusX increases DNA strand breaks in the 0.01-0.05 microM range after 72 h. These results demonstrated the existence of a genotoxic potential for NIV and FusX at low exposure levels and could contribute to the risk assessment process of these toxins that are of growing concern.

PMID: 17161579 [PubMed - indexed for MEDLINE]

54. Toxicon. 2007 Mar 1;49(3):306-17. Epub 2006 Oct 11.

Effects of combinations of Fusarium mycotoxins on the inhibition of macromolecular synthesis, malondialdehyde levels, DNA methylation and fragmentation, and viability in Caco-2 cells.

Kouadio JH, Dano SD, Moukha S, Mobio TA, Creppy EE.

Departement of Toxicology, University of Bordeaux 2, 146, rue Léo Saignat, 33076 Bordeaux, France.

We studied the interactive effects of either binary or tertiary mixtures of Fusarium mycotoxins, deoxynivalenol (DON), zearalenone (ZEA), and fumonisin B1 (FB1) on the human intestinal cell line, Caco-2, using the endpoints including malonedialdehyde (MDA) production, inhibition of protein and DNA syntheses, DNA methylation, DNA fragmentation, and cell viability as measured by the neutral red (NR) test. The mixtures of mycotoxins reduce cellular viability in increasing order: [FB1+ZEA]<[FB1+DON]<[ZEA+DON]<[FB1+DON+ZEA] in NR test. Because FB1 antagonizes the effects of estrogenic Zearalenone, FB1 was assayed against estradiol. In NR assay, mixture of FB1 and estradiol and/or ZEA improves Caco-2 cells viability in contrast to individual effects. Mixtures of ZEA or FB1 and DON, display synergistic effects in lipid peroxidation. The ability of the toxins to inhibit DNA synthesis is 45%, 70%, and 43% for 10 microM of ZEA, DON, and FBI, respectively. Their binary mixtures (at 10 microM each), inhibit DNA synthesis by 35%, 62%, and 65%, far less than additive effects. Surprisingly, the tertiary mixture (10 microM each) only inhibits DNA synthesis by 25%. ZEA, DON, and FB1 induce DNA fragmentation individually. However, mixtures of these mycotoxins always damage DNA to a greater extent. Each individual mycotoxin (10 microM) raises the percentage of 5-methylcytosine (m5dC) in DNA from 4.5% to 9%, while the combination does not increase this rate any further. Altogether, the data indicate that mixtures of Fusarium toxins are able to induce lipid peroxidation, DNA damage, DNA fragmentation, DNA methylation, and cytotoxicity in Caco-2 cells, and suggest a potential promoter effect in human intestinal cells.

PMID: 17109910 [PubMed - indexed for MEDLINE]

55. Toxicol Sci. 2007 Feb;95(2):412-26. Epub 2006 Nov 7.

Deoxynivalenol exacerbates viral bronchopneumonia induced by respiratory reovirus infection.

Li M, Harkema JR, Cuff CF, Pestka JJ.

Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan 48824, USA.

The trichothecene mycotoxin deoxynivalenol (DON), a frequent contaminant of cereal grains, is known to dysregulate mucosal and systemic immunity. In this study, we tested the hypothesis that DON interferes with the murine immune response to viral respiratory infection. Female Balb/c mice (5 weeks old) were orally gavaged with DON (10 mg/kg body weight [bw]) or saline vehicle and then intranasally instilled with 10(7) plaque-forming units of reovirus serotype 1, strain Lang (T1/L). At 10-day postinstillation (PI), both viral titers and reovirus L(2) gene expression were 10-fold higher in lungs of DON-treated mice than in saline controls. The lowest observed effective DON dose that impaired viral clearance was 2 mg/kg bw. Although DON amplified reovirus-induced interferon (IFN)-beta and IFN-gamma mRNA responses in lung, the toxin suppressed mRNA expression for IFN-alpha, IFN-alphabeta receptor (IFNAR), and IFN-gamma receptor (IFNGR). DON also impaired induction of two type 1 IFN-dependent antiviral genes, double-stranded RNA activated protein kinase R (PKR) and oligoadenylate synthase 2 (OAS2). Respiratory reovirus infection caused a mild bronchopneumonia in mice which was markedly exacerbated by DON as evidenced by severe inflammatory cell infiltration, marked alveolar damage, and a higher volume density of intraepithelial mucosubstances in pulmonary airways. At 3- and 7-day PI, elevations in total protein, MCP-1, TNF-alpha, total cells, macrophages, neutrophils, and lymphocytes were observed in bronchoalveolar lavage fluid (BALF) of control mice infected with reovirus. DON markedly enhanced viral-induced elevations of protein, MCP-1, TNF-alpha, and inflammatory cells in the BALF at 3-day PI. DON exposure also upregulated induction of reovirus-specific immunoglobulin A (IgA) in BALF, fecal pellets, and serum. DON's effect on BALF IgA was preceded by elevated IL-6 expression and secretion in the lung. Taken together, the results suggest that DON compromised resistance to respiratory viral infection. Reduced expression of IFNAR and type 1 IFN-mediated genes in the lung might contribute to DON impairment of pulmonary reovirus clearance, whereas exacerbation of bronchopneumonia and IgA responses corresponded to increased MCP-1, TNF-alpha, and IL-6 expression.

PMID: 17090620 [PubMed - indexed for MEDLINE]

56. Toxicol Appl Pharmacol. 2006 Nov 15;217(1):76-85. Epub 2006 Aug 12.

T-2 toxin impairs murine immune response to respiratory reovirus and exacerbates viral bronchiolitis.

Li M, Harkema JR, Islam Z, Cuff CF, Pestka JJ.

Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824-1224, USA.

Exposure to immunosuppressive environmental contaminants is a possible contributing factor to increased occurrence of viral respiratory diseases. The objective of this study was to test the hypothesis that the trichothecene mycotoxin T-2 toxin (T-2), a frequent food contaminant, alters host resistance to lung infection by reovirus, a model respiratory virus. Balb/c mice (4 week old) were treated intraperitoneally with T-2 toxin (1.75 mg/kg bw) or saline vehicle and then intranasally instilled 2 h later with 10(7) plaque forming unit (PFU) of reovirus, strain Lang (T1/L) or saline vehicle. At 10 days post-instillation (PI), both virus plaque-forming responses and reovirus L2 gene expression were 10-fold higher in lungs of T-2-treated mice compared to controls. No-effect and lowest-effect levels for T-2-induced suppression of reovirus clearance were 20 and 200 microg/kg bw, respectively. Respiratory reovirus infection resulted in a mild bronchiolitis with minimal alveolitis, which was markedly exacerbated by T-2 pretreatment. Reovirus exposure induced marked increases in total cells, neutrophils and lymphocytes at 3 and 7 days PI in bronchial alveolar lavage fluid (BALF) whereas macrophages were increased only at 7 days PI. Although prior T-2 exposure attenuated total cell and macrophage counts in BALF of control and infected mice at 3 days PI, the toxin potentiated total cell, macrophage, neutrophil and lymphocyte counts in infected mice at 7 days PI. At 3 days PI, T-2 suppressed reovirus-induced IFN-gamma elevation in BALF, but enhanced production of IL-6 and MCP-1. T-2 pretreatment also suppressed reovirus-specific mucosal IgA responses in lung and enteric tract, but potentiated serum IgA and IgG responses. Taken together, T-2 increased lung viral burden, bronchopneumonia and pulmonary cellular infiltration in reovirus-infected mice. These effects might be attributable to reduced alveolar macrophage levels as well as modulated cytokine and mucosal Ig responses.

PMID: 17005225 [PubMed - indexed for MEDLINE]

57. Environ Health Perspect. 2006 Jul;114(7):1099-107.

Satratoxin G from the black mold Stachybotrys chartarum evokes olfactory sensory neuron loss and inflammation in the murine nose and brain.

Islam Z, Harkema JR, Pestka JJ.

Center for Integrative Toxicology, Department of Microbiology and Molecular Genetics, and Department of Food Science and Human Nutrition, Michigan State University, East Lansing, Michigan, USA.

Satratoxin G (SG) is a macrocyclic trichothecene mycotoxin produced by Stachybotrys chartarum, the "black mold" suggested to contribute etiologically to illnesses associated with water-damaged buildings. Using an intranasal instillation model in mice, we found that acute SG exposure specifically induced apoptosis of olfactory sensory neurons (OSNs) in the olfactory epithelium. Dose-response analysis revealed that the no-effect and lowest-effect levels at 24 hr postinstillation (PI) were 5 and 25 microg/kg body weight (bw) SG, respectively, with severity increasing with dose. Apoptosis of OSNs was identified using immunohistochemistry for caspase-3 expression, electron microscopy for ultrastructural cellular morphology, and real-time polymerase chain reaction for elevated expression of the proapoptotic genes Fas, FasL, p75NGFR, p53, Bax, caspase-3, and CAD. Time-course studies with a single instillation of SG (500 microg/kg bw) indicated that maximum atrophy of the olfactory epithelium occurred at 3 days PI. Exposure to lower doses (100 microg/kg bw) for 5 consecutive days resulted in similar atrophy and apoptosis, suggesting that in the short term, these effects are cumulative. SG also induced an acute, neutrophilic rhinitis as early as 24 hr PI. Elevated mRNA expression for the proinflammatory cytokines tumor necrosis factor-alpha, interleukin-6 (IL-6) , and IL-1 and the chemokine macrophage-inflammatory protein-2 (MIP-2) were detected at 24 hr PI in both the ethmoid turbinates of the nasal airways and the adjacent olfactory bulb of the brain. Marked atrophy of the olfactory nerve and glomerular layers of the olfactory bulb was also detectable by 7 days PI along with mild neutrophilic encephalitis. These findings suggest that neurotoxicity and inflammation within the nose and brain are potential adverse health effects of exposure to satratoxins and Stachybotrys in the indoor air of water-damaged buildings.

PMCID: PMC1513335 PMID: 16835065 [PubMed - indexed for MEDLINE]

58. Food Chem Toxicol. 2006 Aug;44(8):1228-35. Epub 2006 Feb 23.

Influence of diets with cereal grains contaminated by graded levels of two Fusarium toxins on selected enzymatic and histological parameters of liver in gilts.

Tiemann U, Brüssow KP, Küchenmeister U, Jonas L, Kohlschein P, Pöhland R, Dänicke S.

Unit of Reproductive Biology, FBN Research Institute for the Biology of Farm Animal, Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany.

Feeding experiments with diets containing Fusarium toxin-contaminated wheat were conducted to clarify the pathogenesis of enzymatic and histopathological effects of Fusarium toxins on porcine liver cells. A total of 36 prepuberal gilts were divided into four groups and fed diets with increasing proportions of Fusarium toxin-contaminated wheat at a total wheat proportion of 40% over a period of 35 days. The concentrations of the indicator toxins deoxynivalenol (DON) and zearalenone (ZON) which were analyzed by HPLC methods were 210/4, 3070/88, 6100/235, and 9570/358 microg/kg in the diets fed to groups I-IV, respectively. The feeding of mycotoxin-contaminated diets did not cause gross pathological findings in the livers of the animals. Liver tissues were subjected to enzymatic, histological, and ultrastructural examinations. The percentages of the stained areas in periodic acid-Schiff (PAS), Berlin-Blue, and Masson Goldner's trichrome stainings were calculated using the AnalySIS 3.4-system. Significant histopathological findings of alterations with varying degrees in glycogen reduction and increase of hemosiderin particles were found in the liver cells of groups II, III and IV. The thickness of interlobular connective tissue septum in liver cells was significantly increased in groups III and IV. Qualitative ultrastructural alterations were observed in hepatocytes of gilts in groups III and IV. Dependent upon the mycotoxin concentration in the diet, the hepatocytes developed a dose-dependent, extensive, smooth endoplasmic reticulum, exhibited loss of ribosomes, and acquired an increased number of fatty and autophagic vacuoles. However, liver damage as measured by prominent elevated transaminase activities in serum was not detected. Together, the histopathological results provide evidence of liver dysfunction in the absence of clinical signs, especially in pigs fed higher concentrations of Fusarium toxin-contaminated wheat.

PMID: 16580769 [PubMed - indexed for MEDLINE]

59. Food Chem Toxicol. 2006 Jun;44(6):747-57. Epub 2005 Dec 2.

Effects of deoxynivalenol (DON, vomitoxin) on in utero development in rats.

Collins TF, Sprando RL, Black TN, Olejnik N, Eppley RM, Hines FA, Rorie J, Ruggles DI.

Center for Food Safety and Applied Nutrition, US Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708, USA.

Deoxynivalenol (DON, vomitoxin), is one of the most common contaminants of cereal grains world-wide. The effects of DON on fetal development were assessed in Charles River Sprague-Dawley rats. Pregnant female rats were gavaged once daily with DON at doses of 0, 0.5, 1, 2.5, or 5 mg/kg body weight on gestation days (GD) 6-19. At cesarean section on GD 20, reproductive and developmental parameters were measured. All females survived to cesarean section. DON caused a dose-related increase in excessive salivation by the pregnant females, a reaction probably linked to the lack of emetic reflex in rats. At 5 mg/kg, feed consumption and mean body weight gain were significantly decreased throughout gestation, mean weight gain (carcass weight), and gravid uterine weight were significantly reduced, 52% of litters (12/23) were totally resorbed, the average number of early and late deaths per litter was significantly increased, average fetal body weight and crown-rump length were significantly decreased, the incidence of runts was significantly increased, and the ossification of fetal sternebrae, centra, dorsal arches, vertebrae, metatarsals, and metacarpals was significantly decreased. At 2.5 mg/kg, DON significantly decreased average fetal body weight, crown-rump length, and vertebral ossification. These effects may be secondary to maternal toxicity and the reduced size of the fetuses. The incidence of misaligned and fused sternebrae was significantly increased at 5.0 mg/kg. No adverse developmental effects were observed at 0.5 and 1.0 mg/kg. Dose-related increases in maternal liver weight-to-body weight ratios were observed in all treated groups (significant at 1, 2.5, and 5 mg/kg). The weight changes were correlated with dose-related cytoplasmic alterations of hepatocytes. The NOEL for maternal toxicity for this study is 0.5 mg/kg based on the dose-related increase in liver-body weight ratio at 1 mg/kg. The NOEL for fetal toxicity is 1 mg/kg based on the general reduction in fetal development at 2.5 and 5 mg/kg. DON is considered a teratogen at 5 mg/kg day in Sprague-Dawley rats based on the anomalous development of the sternebrae.

PMID: 16325976 [PubMed - indexed for MEDLINE]

60. Exp Toxicol Pathol. 2005 Aug;57(1):15-28.

Microarray analysis of T-2 toxin-induced liver, placenta and fetal liver lesions in pregnant rats.

Sehata S, Kiyosawa N, Atsumi F, Ito K, Yamoto T, Teranishi M, Uetsuka K, Nakayama H, Doi K.

Medicinal Safety Research Laboratories, Sankyo Co., Ltd., 717 Horikoshi, Fukuroi-shi, Shizuoka 437-0065, Japan.

Pregnant rats on day 13 of gestation were treated orally with 2 mg/kg of T-2 toxin and sacrificed at 1, 3, 6, 9 and 12 h after the treatment (HAT). Histopathologically, the number of apoptotic cells was increased in the liver, placenta and fetal liver (peaked at 6, 12 and 9-12 HAT, respectively). To examine the gene expression profiles, we performed microarray analysis of these tissues at two selected time points based on the results of the TdT-mediated dUTP nick end labeling (TUNEL) staining. Increased expression of oxidative stress- and apoptosis-related genes was detected in the liver of dams, placenta and fetal liver of pregnant rats treated with T-2 toxin at the peak time point of apoptosis. Decreased expression of lipid metabolism- and drug-metabolizing enzyme-related genes was also detected in these tissues. The results suggested that the mitogen-activated protein kinase (MAPK) pathway might be involved in the mechanism of T-2 toxin-induced apoptosis. In addition, increased expression of the c-jun gene was consistently observed in these tissues. Our results suggest that the mechanism of T-2 toxin-induced toxicity in pregnant rats is due to oxidative stress followed by the activation of the MAPK pathway, finally inducing apoptosis. The c-jun gene may play an important role in T-2 toxin-induced apoptosis.

PMID: 16089316 [PubMed - indexed for MEDLINE]

61. Biol Pharm Bull. 2005 Jun;28(6):1025-30.

Two related cinnamic Acid derivatives from Brazilian honey bee propolis, baccharin and drupanin, induce growth inhibition in allografted sarcoma S-180 in mice.

Mishima S, Ono Y, Araki Y, Akao Y, Nozawa Y.

API Co. Ltd., R&D, Gifu, Japan.

Honey bee propolis is rich in cinnamic acid derivatives. Baccharin and drupanin from Brazilian honey bee propolis are cinnamic acid derivatives that contain prenyl moieties. We previously isolated these two compounds and demonstrated that they induce an apoptotic event in several tumor cell lines. In this study, we examined the tumoricidal activity of baccharin and drupanin in mice allografted with sarcoma S-180 and also studied the genotoxic effects on normal splenocytes using the alkaline single cell gel (comet) assay. We found that both baccharin and drupanin effectively suppressed growth of the tumor. Furthermore, these compounds induced a significant genotoxic effect on the tumor cells in comparison with normal splenocytes. Thus, baccharin and drupanin are potent tumor suppressive components of honeybee propolis.

PMID: 15930739 [PubMed - indexed for MEDLINE]

62. Toxicol Sci. 2005 Jun;85(2):916-26. Epub 2005 Mar 16.

Ribotoxic stress response to the trichothecene deoxynivalenol in the macrophage involves the SRC family kinase Hck.

Zhou HR, Jia Q, Pestka JJ.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing, Michigan 48824-1224, USA.

Trichothecene mycotoxins and other translational inhibitors activate mitogen-activated protein kinase (MAPKs) by a mechanism called the "ribotoxic stress response," which drives both cytokine gene expression and apoptosis in macrophages. The purpose of this study was to identify upstream kinases involved in the ribotoxic stress response using the trichothecene deoxynivalenol (DON) and the RAW 264.7 macrophage as models. DON (100 to 1000 ng/ml) dose-dependently induced phosphorylation of c-Jun N-terminal protein kinase (JNK), extracellular signal-regulated kinase (ERK), and p38 MAPKs. MAPK phosphorylation in response to DON exposure occurred as early as 5 min, was maximal from 15 to 30 min, and lasted up to 8 h. Preincubation with inhibitors of protein kinase C, protein kinase A, or phospholipase C had no effect on DON-induced MAPK phosphorylation. In contrast, the Src family tyrosine kinase inhibitors, PP1 (4-amino-5-[4-methylphenyl)]-7-[t-butyl]pyrazolo[3,4-d]-pyrimidine) and, PP2 (4-amino-5-[4-chlorophenyl]-7-[t-butyl]pyrazolo[3,4-d]-pyrimidine) concentration-dependently impaired phosphorylation of all three MAPK families. PP1 suppressed DON-induced phosphorylation of the MAPK substrates c-jun, ATF-2, and p90(Rsk). MAPK phosphorylation by two other translational inhibitors, anisomycin and emetine, were similarly Src-dependent. PP1 reduced DON-induced increases in nuclear levels and binding activities of several transcription factors (NF-kappaB, AP-1, and C/EBP), which corresponded to decreases in TNF-alpha production, caspase-3 activation, and apoptosis. Tyrosine phosphorylation of hematopoeitic cell kinase (Hck), a Src found in macrophages, was detectable within 1 to 5 min after DON addition, and this was suppressed by PP1. Knockdown of Hck expression with siRNAs confirmed involvement of this Src in DON-induced TNF-alpha production and caspase activation. Taken together, activation of Hck and possibly other Src family tyrosine kinases are likely to be critical signals that precede both MAPK activation and induction of resultant downstream sequelae by DON and other ribotoxic stressors.

PMID: 15772366 [PubMed - indexed for MEDLINE]

63. Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi. 2005 Mar;21(2):246-8.

[The inhibitory effect of deoxynivalenol on TAP-1 expression in human peripheral blood mononuclear cells in vitro].

[Article in Chinese]

Li YH, Zhang XH, Xing LX, Yan X, Wang JL, Wang FR.

Lab.of Experiment Pathology, Hebei Medical University, Shijiazhuang 050017, China.

AIM: To explore the effects of deoxynivalenol (DON) on transporter associated with antigen processing-1 (TAP-1) expression in human peripheral blood mononuclear cells (PBMCs). METHODS: Effects of various concentrations of DON on TAP-1 expression of in vitro cultured human PBMCs and the dose-effect relationship were analyzed by flow cytometry (FCM) and semi-quantitative RT-PCR at the protein and mRNA levels. RESULTS: FCM analysis indicated that treatment with various concentrations of DON could inhibit TAP-1 expressions in PBMCs, showing a negative correlation between DON concentration and TAP-1 expression. Semi-quantitative RT-PCR detection indicated that high concentrations of DON (1,000 and 2,000 microg/L) could distinctly inhibit TAP-1 mRNA expression. CONCLUSION: DON can down-regulate TAP-1 expression in human PBMCs in a dose-dependent manner in vitro, which suggests DON may interfere with host immunosurveillance, and this may account for the correlation between DON-contaminated grain and esophagus cancer in high risk area.

PMID: 15766417 [PubMed - indexed for MEDLINE]

64. Zhonghua Zhong Liu Za Zhi. 2004 Dec;26(12):705-8.

[Carcinogenic effects of sterigmatocystin and deoxynivalenol in NIH mice].

[Article in Chinese]

Huang XH, Zhang XH, Li YH, Wang JL, Yan X, Xing LX, Wang FR.

Laboratory of Experimental Pathology, Hebei Medical University, Shijiazhuang, Hebei 050017, China.

OBJECTIVE: To further explore the carcinogenic activity of Sterigmatocystin (ST) and the possible synergistic carcinogenic effect of deoxynivalenol (DON) in NIH mice. METHODS: NIH mice were randomly divided into 6 groups, 30 in each. Five groups of mice were given by gastric intubation ST 3 microg/kg, ST 30 microg/kg, ST 3 microg/kg + DON 1.5 microg/kg, ST 30 microg/kg + DON 1.5 microg/kg and DON 1.5 microg/kg respectively, 3 times a week for 24 weeks. The remaining group of mice was given normal saline accordingly, serving as control. All mice were fed with HPLC-confirmed mycotoxin-free food, analysis. The mice were killed and pathologically examined at 58th and 74th weeks. RESULTS: No pathological changes were found in the control group of mice. Adenocarcinoma of lung was observed in 25.0%, 41.7%, 62.5%, 69.2% and 37.5% of mice given ST 3 microg/kg, ST 30 microg/kg, ST 3 microg/kg + DON 1.5 microg/kg, ST 30 microg/kg + DON 1.5 microg/kg and DON 1.5 microg/kg, respectively. In addition, dysplasia of glandular stomach was detected in 50.0%, 58.3%, 37.5%, 53.8% and 25.0% of mice similarly treated. CONCLUSION: Oral administration of ST or DON can induce adenocarcinoma in lung and dysplasia of glandular stomach in NIH mice. There is synergistic carcinogenic effect when both ST and DON are given.

PMID: 15733384 [PubMed - indexed for MEDLINE]

65. Food Chem Toxicol. 2005 Apr;43(4):623-35.

Characterization of the effect of deoxynivalenol on selected male reproductive endpoints.

Sprando RL, Collins TF, Black TN, Olejnik N, Rorie JI, Eppley RM, Ruggles DI.

Food and Drug Administration, Division of Toxicology and Nutritional Product Studies, Office of Applied Research and Safety Assessment, Center for Food Safety and Applied Nutrition, Laurel, MD 20708, USA.

The effect of deoxynivalenol (DON) exposure on male reproductive function was assessed in the rat. Male rats were divided into a control group (n=15 rats) and four treatment groups (0.5 mg/kg, n=15; 1.0 mg/kg, n=15; 2.5 mg/kg, n=15; and 5.0 mg/kg DON, n=16) and exposed to DON daily for 28 days via gastric intubation. Both body weight gain and the final body weight of animals in the 5.0 mg/kg dose group and feed consumption in animals in the 2.5 mg/kg and 5.0 mg/kg dose groups were significantly reduced compared to controls. Fluid consumption was not affected in any of the treated groups. Epididymal and seminal vesicle weights expressed per gram of body weight and brain weight were significantly reduced, compared to control weights, in animals from the 2.5 and 5.0 mg/kg dose groups while prostate weight expressed per gram of brain weight and body weight was significantly lower than controls only in the 5.0 mg/kg dose group. A statistically significant, dose-related decrease in homogenization resistant testicular spermatid counts, spermatid numbers, absolute cauda epididymal sperm numbers and cauda epididymal sperm numbers per gram of cauda epididymis was observed in the 5.0 mg/kg DON treatment group. Sperm tail abnormalities (broken tails) in the 5.0 mg/kg dose group were significantly higher than in the control group. Sperm swimming speed (VSL and VCL) was significantly increased only in the 2.5 mg/kg dose group. Serum FSH and LH concentrations were increased in a dose dependent manner across all treated groups while serum testosterone concentrations were decreased in a dose-related manner across all dose groups. An increase in germ cell degeneration, sperm retention and abnormal nuclear morphology was observed in the 2.5 mg/kg and 5.0 mg/kg dose groups. Treatment related effects included lesions in the non-glandular stomach, thymic lymphoid depletion and splenic hematopoiesis in the 5.0 mg/kg treatment group.

PMID: 15721211 [PubMed - indexed for MEDLINE]

66. Exp Mol Pathol. 2005 Apr;78(2):144-9.

T-2 toxin-induced apoptosis in rat keratinocyte primary cultures.

Albarenque SM, Doi K.

Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan.

T-2 toxin, a kind of trichothecene mycotoxins produced by the genus Fusarium, induces apoptosis in basal keratinocytes when topically applied to the dorsal skin of rats. In the present study, direct effects of T-2 toxin on keratinocyte primary cultures obtained from newborn rats were examined after the third passage. Keratinocyte medium containing 0.25 microg/ml of T-2 toxin dissolved in dimethyl sulfoxide or solvent alone was added to 4-day cultures and incubated at 37 degrees C. At 0.5, 1, 3, 5, 7, and 9 h after treatment (h), feeder layer was separated from flasks, and cells were trypsinized. Cell viability was estimated by trypan blue exclusion method. In addition, RNA was obtained and RT-PCR was performed. Samples obtained from slide cultures at 3, 6, 9, and 12 h were fixed in 4% paraformaldehyde or 2.5% glutaraldehyde for morphological examination. After T-2 toxin application, cell viability decreased to 40% at 3 h. At 6 h, small-sized keratinocytes showed pyknosis or karyorrhexis, resulting in detachment from slides. The number of such cells increased until 12 h. These small-sized keratinocytes showed ultrastructural changes characteristic for apoptosis. At the same time, large squamous keratinocytes showed intracytoplasmic edema. The expression of apoptosis-related genes (c-fos and c-jun) and cytokines (TNF-alpha and IL-1beta) mRNAs markedly increased before the development of apoptosis. These findings indicate that c-fos and c-jun oncogenes and TNF-alpha and IL-1beta play an important role in the development of T-2 toxin-induced apoptosis in keratinocytes.

PMID: 15713441 [PubMed - indexed for MEDLINE]

67. Toxicol Sci. 2005 Apr;84(2):408-17. Epub 2005 Jan 12.

Acute inflammatory responses to Stachybotrys chartarum in the lungs of infant rats: time course and possible mechanisms.

Yike I, Rand TG, Dearborn DG.

Mary Ann Swetland Center for Environmental Health, Case Western Reserve University, Cleveland, Ohio 44106-3029, USA.

Stachybotrys chartarum has been linked to building-related respiratory problems including pulmonary hemorrhage in infants. The macrocyclic trichothecenes produced by S. chartarum have been the primary focus of many investigations. However, in addition to trichothecenes this fungus is capable of producing other secondary metabolites and a number of protein factors. This study examines the effects of intact, autoclaved, and ethanol-extracted spores on the lungs of infant rats as an approach to differentiate between secondary metabolites and protein factors. Seven-day-old infant rats were exposed intratracheally to 1 x 10(5) spores/g body weight (toxic strain JS58-17) and sacrificed at various times up to 72 h. The inflammatory response was measured by morphometric analysis of the lungs and determination of inflammatory cells and cytokine concentrations in bronchoalveolar lavage (BAL) fluid. Alveolar space was greatly reduced in animals exposed to fungal spores compared to phosphate buffered saline (PBS)-treated controls. The largest effects were observed in pups treated with intact spores where alveolar space 24 h after treatment was 42.1% compared to 56.8% for autoclaved spores, 51.1% for ethanol-extracted spores, and 60.6% for PBS-treated controls. The effects of different spore preparations on inflammatory cells, cytokine, and protein concentrations in the BAL fluid can be ranked as intact > autoclaved > extracted. Tumor necrosis factor alfa (TNF-alpha), interleukin 1-beta (IL-1beta), and neutrophils were the most sensitive indicators of inflammation. The difference between autoclaved (100% trichothecene toxicity, denatured/enzymatically inactive proteins) and intact (100% trichothecene activity, unaltered/released proteins) spores indicates the involvement of fungal proteins in the inflammatory response to S. chartarum and sheds new light on the clinical importance of "nontoxic" strains.

PMID: 15647601 [PubMed - indexed for MEDLINE]

68. Arch Anim Nutr. 2004 Oct;58(5):413-7.

The effect of increasing concentrations of Fusarium toxins in piglet diets on histological parameters of the uterus and vagina.

Döll S, Dänicke S, Schnurrbusch U.

Institute of Animal Nutrition, Federal Agricultural Research Centre (FAL), Braunschweig, Germany.

The effects of feeding diets containing 0.01, 0.06, 0.15, 0.22 and 0.42 mg zearalenone and 0.2, 0.8, 1.0, 1.9 and 3.9 mg deoxynivalenol per kg, originating from Fusarium toxin contaminated maize, on the uterus of 50 prepubertal piglets (10 pigs per treatment; BW 32.6+/-5.4 kg; approximately 70 days of age) were investigated. The mean weight of the uteri of animals receiving the most highly contaminated diet was significantly increased at the time of slaughtering. The histological investigation showed no marked differences between the feeding groups. Histometrical parameters of the surface epithelium of the uterus, of the uterine glands and the vaginal epithelium were not altered by the treatment.

PMID: 15595624 [PubMed - indexed for MEDLINE]

69. Toxicology. 2004 Nov 15;204(2-3):241-9.

Porcine hepatocyte apoptosis and reduction of albumin secretion induced by deoxynivalenol.

Mikami O, Yamamoto S, Yamanaka N, Nakajima Y.

Toxico-Pathology Section, Department of Safety Research, National Institute of Animal Health, Tsukuba, Ibaraki, 305-0856, Japan.

Deoxynivalenol (DON) is one of the major mycotoxic contaminants of grains, which causes reduced weight gain in pigs. The cytotoxicity of DON to porcine hepatocytes was examined in this study. DON was added at the final concentration of 100, 10, 1, 0.1 or 0.01 microg/ml to the medium of primary cultured hepatocytes. Cell death of the hepatocytes was observed in DON 100 and 10 microg/ml groups from 6 h after the addition, and in DON 100, 10, 1 and 0.1 microg/ml groups at 24 h in a dose-dependent manner. The dead hepatocytes showed chromatin condensation and fragmentation of the nuclei, which are considered characteristic morphological changes of apoptosis. The nuclei of the dead hepatocytes were stained positively by the TUNEL method. Lactate dehydrogenase (LDH) release, which is considered leakage from apoptotic hepatocytes into the medium, was apparent at 24 h after DON addition. Increased caspase-3 activity was seen in DON 100, 10 and 1 microg/ml groups. Albumin secretion into the medium was significantly reduced in DON 100, 10 and 1microg/ml groups, moderately in the 0.1 microg/ml group, and slightly in the 0.01 microg/ml group. These results indicate that DON induced apoptosis through the caspase-3 activation pathway and caused functional disorder in porcine hepatocytes.

PMID: 15388250 [PubMed - indexed for MEDLINE]

70. Exp Mol Pathol. 2004 Oct;77(2):149-52.

Development of early apoptosis and changes in T-cell subsets in mouse thymocyte primary cultures treated with nivalenol.

Poapolathep A, Kumagai S, Suzuki H, Doi K.

Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.

Nivalenol (NIV), a trichothecene mycotoxin, is a secondary fungal metabolite mainly produced by Fusarium nivale. We first reported that NIV could induce apoptosis and changes in lymphocyte subsets in lymphoid tissues of mice. In this study, to clarify the direct effects of NIV on thymocytes, mouse thymocyte primary cultures were treated with NIV at the dose levels of 0.25, 0.5 and 1.0 microg/ml and examined for up to 24 h after treatment by flow cytometry. The number of viable cells decreased significantly at and after 6 h in dose- and time-dependent manners, and FACS analysis revealed that the apoptotic cell index showed a significant increase in all treated groups at and after 3 h in a time-dependent manner. The index at 24 h was lowest in 1.0 microg/ml-group. The number of CD4(+)CD8(+) cells was prominently depleted in all groups in a time-dependent manner. On the other hand, the numbers of CD4(+)CD8(-) and CD4(-)CD8(+) cells were significantly depleted only in 1.0 microg/ml-group at 24 HAT. These results indicate that NIV directly affects thymocytes and induces apoptosis mainly in CD4(+)CD8(+)cells.

PMID: 15351239 [PubMed - indexed for MEDLINE]

71. Food Chem Toxicol. 2004 Nov;42(11):1727-36.

Morphological and microarray analysis of T-2 toxin-induced rat fetal brain lesion.

Sehata S, Kiyosawa N, Makino T, Atsumi F, Ito K, Yamoto T, Teranishi M, Baba Y, Uetsuka K, Nakayama H, Doi K.

Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.

To examine morphological and gene expression changes induced by T-2 toxin in the fetal brain in detail, pregnant rats on day 13 of gestation were treated orally with a single dose of T-2 toxin (2 mg/kg) and sacrificed at 1, 3, 6, 9, 12 and 24 h after treatment (HAT). Histopathologically, the number of apoptotic neuroepithelial cells in the telencephalon increased from 1 HAT and peaked at 12 HAT. Based on the histopathological examinations, microarray analysis was performed at 6, 12 and 24 HAT. Microarray analysis showed that the expression of oxidative stress-related genes (heat shock protein 70 (HSP70) and heme oxygenase (HO)) was strongly induced by T-2 toxin at 12 HAT, the peak time point of apoptosis induction. The expression of mitogen-activated protein kinase (MAPK)-related genes (MEKK1 and c-jun) and other apoptosis-related genes (caspase-2 and insulin-like growth factor-binding protein-3 (IGF-BP3)) was also induced by the T-2 toxin treatment. The changes observed by microarray analysis were confirmed for four up-regulated genes (HSP70, HO, IGF-BP3 and VEGF-A) using real-time RT-PCR. Our results suggest that the T-2 toxin-induced apoptosis in the fetal brain is due to oxidative stress, and that the MAPK pathway may be involved in T-2 toxin-induced toxicity.

PMID: 15350670 [PubMed - indexed for MEDLINE]

72. Am J Chin Med. 2004;32(3):377-87.

4-Acetyl-12,13-epoxyl-9-trichothecene-3, 15-diol from Isaria japonica mediates apoptosis of rat bladder carcinoma NBT-II cells by decreasing anti-apoptotic Bcl-2 expression and increasing pro-apoptotic Bax expression.

Kim HJ, Jang SI, Kim YJ, Pae HO, Won HY, Hong KH, Oh H, Kwon TO, Chung HT.

Immunopia Research Laboratory of Molecular and Cellular Immunology, Wonkwang University, Iksan, Chonbuk 570-749, South Korea.

We studied the effect of 4-acetyl-12,13-epoxyl-9-trichothecene-3, 15-diol (AETD) isolated from Isaria japonica, one of the most popular Chinese fungal medicines, on the induction of apoptosis in rat bladder carcinoma NBT-II cells. AETD was cytotoxic to NBT-II cells, and this cytotoxic effect appears to be attributed to its induction of apoptotic cell death, as AETD induced nuclear morphological changes and internucleosomal DNA fragmentation, and increased the proportion of hypodiploid cells and activity of caspase-3. AETD treatment also decreased the expression of the anti-apoptotic protein Bcl-2 and increased the expression of the pro-apoptotic protein Bax. These results provide important information in understanding the mechanism(s) of AETD-induced apoptosis.

PMID: 15344421 [PubMed - indexed for MEDLINE]

73. Oncol Rep. 2004 Aug;12(2):449-56.

Nivalenol, a main Fusarium toxin in dietary foods from high-risk areas of cancer of esophagus and gastric cardia in China, induced benign and malignant tumors in mice.

Hsia CC, Wu ZY, Li YS, Zhang F, Sun ZT.

Laboratory of Hepatitis and Related Emerging Agents, Division of Emerging and Transfusion Transmitted Diseases, Center for Biologics Evaluation and Research, FDA, Bethesda, MD, USA.

This is the first report that a Fusarium toxin nivalenol (NIV) naturally existing at high levels in dietary food in high-risk areas of cancer of esophagus and gastric cardia in China induced benign and malignant tumors in mice. The levels of two Fusarium toxins, nivalenol and deoxynivalenol (DON) were quantitated using high performance liquid chromatography (HPLC) in a total of 97 samples of dietary wheat flour, barley and corn collected from families in two areas with high mortality rate of cancer of esophagus and gastric cardia (132/100,000), Linxian, Henan province and Cixiang, Hepei province, China. The mean level of NIV and DON in three dietary foods was 830+/-927 microg/kg (range 584-1,780 microg/kg) and 4,281+/-6,114 microg/kg (range 732-10,980 microg/kg) respectively. The highest mean level of NIV was 1,780+/-1,705 microg/kg found in barley from Linxian, that of DON was 10,980+/-10,139 microg/kg found in corn from Cixiang. NIV was undetectable in 2 samples of rice from USA. The mean levels of NIV in three main dietary foods in those two high-risk areas were estimated at 400 to 800-fold higher than that in the USA, where NIV was undetectable in dietary food, and the mortality rate of esophageal cancer is <5/100,000 in white Caucasians in the USA, (odds ratio was estimated at 17-34, p<0.000005). These data suggest that Linxian and Cixiang peasants who consumed a diet with high NIV had significantly higher risk for developing esophageal cancer than the US residents who consumed food without or with negligible amounts of NIV. Three repeated experiments were performed using Balb/C mice with inter-mittent application of NIV, alternate with 12-Tetradeconoyl-phorbol-13-acetate (TPA) application on skin. Papillomas and carcinomas developed in a total of 23/49 (47%) mice that survived 11-60 weeks of experiments. Among all the tumors, 4 carcinomas in 3 mice were identified. No tumors were found in the 60 control mice applying either TPA or acetone (solvent) only on skin.

PMID: 15254715 [PubMed - indexed for MEDLINE]

74. Toxicon. 2004 Jul;44(1):111-3.

Placental and milk transmission of trichothecene mycotoxins, nivalenol and fusarenon-X, in mice.

Poapolathep A, Sugita-Konishi Y, Phitsanu T, Doi K, Kumagai S.

Department of Veterinary Pathology, Yayoi 1-1-1, Bunkyo, Tokyo 113-8657, Japan.

In order to investigate the transfer of nivalenol (NIV) and fusarenon-X (FX) from pregnant to fetal mice and from lactating to suckling mice, (3)H-NIV or (3)H-FX was given p.o. to pregnant or lactating mice. Radioactivity was detected in the whole fetal tissues as well as the fetal liver and kidney, the levels being comparable to those of the maternal tissues. Radioactivity was also detected in the milk, and liver and kidney tissues taken from suckling mice of both (3)H-NIV or (3)H-FX administered dams. HPLC analysis of fetal tissue homogenates from non-labeled FX- or NIV-administered pregnant mice revealed transmission of NIV to fetuses after administration of either toxin. In mice given the non-labeled FX, major and minor peaks of NIV and FX on HPLC were noted in suckling pup tissue homogenates. The results demonstrate that NIV transfers in unchanged form to fetal or suckling mice via placenta or milk, respectively, and that FX does so mainly after being metabolized to NIV in maternal body.

PMID: 15225570 [PubMed - indexed for MEDLINE]

75. Southeast Asian J Trop Med Public Health. 2003 Dec;34(4):899-905.

Effects of elephant garlic volatile oil (Allium ampeloprasum) and T-2 toxin on murine skin.

Nguansangiam S, Angsubhakorn S, Bhamarapravati S, Suksamrarn A.

Department of Pathology, Bangkok Metropolitan Administration Medical College and Vajira Hospital, Bangkok, Thailand.

Effects of elephant garlic (Allium ampeloprasum) volatile oil (GVO) and trichothecene (T-2) toxin were studied in Swiss albino mice. The animals were 1) topically applied GVO, 2) topically applied T-2 toxin, 3) topically applied GVO followed by T-2 toxin (GVO/T-2), and 4) T-2 toxin application followed by GVO (T-2/GVO) on the right footpad. All animals were observed by Langerhans cell enumeration and pathological changes of the footpad on days 1, 3, 5 and 7. The number of Langerhans cells in the GVO treated group (1,097 +/- 33/mm2 to 1,624 +/- 19/mm2) was not significantly different when compared with the corresponding control left footpad (1,143 +/- 33/mm2 to 1,674 +/- 21/mm2). Langerhans cells density in T-2 toxin treated group (629 +/- 29/mm2to 1,090 +/- 31/mm2) was reduced by 20-35% of the opposite control footpad (962 +/- 40/mm2 to 1,392 +/- 29/mm2). Furthermore, GVO/T-2 and T-2/GVO treated mice showed a decrease in Langerhans cell number than a single T-2 toxin treated group. While Langerhans cells in T-2 toxin, GVO/T-2 and T-2/GVO groups revealed a smaller cell size with shortening dendritic processes when compare to the normal control group. Histopathological findings of the footpad skin in T-2 toxin treated group revealed epidermal desquamation and necrosis with edema and inflammatory cells infiltration. While GVO/T-2 and T-2/GVO showed a similar sequence but a lesser severe degree. These findings suggested that GVO both in pre- and posttreatment could protect T-2 toxin induced epidermal damage in a mouse footpad.

PMID: 15115108 [PubMed - indexed for MEDLINE]

76. Exp Toxicol Pathol. 2004 Mar;55(5):357-66.

Gene expression profiles in pregnant rats treated with T-2 toxin.

Sehata S, Kiyosawa N, Sakuma K, Ito K, Yamoto T, Teranishi M, Uetsuka K, Nakayama H, Doi K.

Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.

Pregnant rats on day 13 of gestation were treated orally with T-2 toxin at a single dose of 2 mg/kg and sacrificed at 24 hours after treatment. Histopathologically, apoptosis was increased in the liver, placenta and fetal liver. Microarray analysis was performed to examine the gene expression in the liver, placenta, and fetal liver. The results of microarray analysis showed that the changes in the expression of apoptosis genes, metabolic enzymes and oxidative stress-related genes were detected in these tissues. Suppression of phase I and II enzymes-related genes expression in the liver, and suppression of phase II enzymes-related genes expression in the placenta and fetal liver were observed. Semiquantitive RT-PCR analysis also showed the same results as those of microarray analysis. From the results of microarray analysis and histopathological examination, T-2 toxin seems to induce oxidative stress in these tissues, following the changes in metabolism-related genes expression. These changes may alter the intracellular environments resulting in the induction of apoptosis. Further studies on the gene expression profiles at the earlier time point are necessary to clarify the detailed mechanisms of T-2 toxin-induced toxicity in pregnant rats.

PMID: 15088637 [PubMed - indexed for MEDLINE]

77. J Food Prot. 2004 Mar;67(3):536-43.

Multiplex real-time PCR detection of fumonisin-producing and trichothecene-producing groups of Fusarium species.

Bluhm BH, Cousin MA, Woloshuk CP.

Department of Botany and Plant Pathology, Purdue University, 915 West State Street, West Lafayette, Indiana 47907, USA.

Some species of Fusarium can produce mycotoxins during food processing procedures that facilitate fungal growth, such as the malting of barley. The objectives of this study were to develop a 5' fluorogenic (Taqman) real-time PCR assay for group-specific detection of trichothecene- and fumonisin-producing Fusarium spp. and to identify Fusarium graminearum and Fusarium verticillioides in field-collected barley and corn samples. Primers and probes were designed from genes involved in mycotoxin biosynthesis (TRI6 and FUM1), and for a genus-specific internal positive control, primers and a probe were designed from Fusarium rDNA sequences. Real-time PCR conditions were optimized for amplification of the three products in a single reaction format. The specificity of the assay was confirmed by testing 9 Fusarium spp. and 33 non-Fusarium fungal species. With serial dilutions of purified genomic DNA from F. verticillioides, F. graminearum, or both as the template, the detection limit of the assay was 5 pg of genomic DNA per reaction. The three products were detectable over four orders of magnitude of template concentration (5 pg to 5 ng of genomic DNA per reaction); at 50 ng template per reaction, only the TRI6 and FUM1 PCR products were detected. Barley and corn samples were evaluated for the presence of Fusarium spp. with traditional microbiological methods and with the real-time PCR assay. The 20 barley samples and 1 corn sample that contained F. graminearum by traditional methods of analysis tested positive for the TRI6 and internal transcribed spacer (ITS) PCR products. The five corn samples that tested positive for F. verticillioides by traditional methods also were positive for the FUMI and ITS PCR products. These results indicate that the described multiplex real-time PCR assay provides sensitive and accurate differential detection of fumonisin- and trichothecene-producing groups of Fusarium spp. in complex matrices.

PMID: 15035370 [PubMed - indexed for MEDLINE]

78. Pharmazie. 2004 Jan;59(1):42-9.

Apoptosis induction by 4beta-acetoxyscirpendiol from Paecilomyces tenuipes in human leukaemia cell lines.

Han HC, Lindequist U, Hyun JW, Kim YH, An HS, Lee DH, Kim HW.

Department of Life Science, University of Seoul, Korea.

The carpophores of Paecilomyces tenuipes are known in the Orient for their strong antitumor activity. In continuation of our study on acetoxyscirpendiol (ASD, 4beta-acetoxyscirpene-3alpha,15-diol) as a cytotoxic component from this fungus, we report particularly on the mode of action of ASD in inducing apoptosis in human MOLT-4, THP-1 and Jurkat T cell leukaemia in vitro. The antiproliferative effects of ASD seem attributable to its induction of apoptosis in the cells, as it blocked the cell cycle, induced hypodiploidity and bound annexin V and also cleaved poly-(ADP-ribose) polymerase (PARP) in these cell lines. The 50% inhibitory concentrations (IC50) of ASD on MOLT-4, THP-1 and Jurkat T cells were found to be 60, 85 and 60 ng/ml, respectively. ASD arrested the cell cycle at the G1/S transition and showed hypodiploidity due to the accumulation of sub-G0 population. Annexin V binding was increased in the presence of ASD in the MOLT-4 cell line in a time-dependent manner. ASD and three of its derivatives also induced cleavage of PARP in both MOLT-4 and Jurkat T cell lines. From these data, it is suggested that ASD exerts its cytotoxic activity by inducing apoptosis in leukaemia cell lines in vitro.

PMID: 14964421 [PubMed - indexed for MEDLINE]

79. Toxicol Sci. 2004 Apr;78(2):267-75. Epub 2004 Jan 12.

Comparison of inflammatory and cytotoxic lung responses in mice after intratracheal exposure to spores of two different Stachybotrys chartarum strains.

Flemming J, Hudson B, Rand TG.

Department of Biology, Saint Mary's University, 923 Robie St., Halifax, Nova Scotia, Canada B3H 3C3.

Stachybotrys chartarum is an important toxigenic fungus that has been associated with respiratory disease onset in animals and humans. While it can be separated into macrocyclic trichothecene- and atranone-producing chemotypes based on secondary metabolite production, effects of spores of the two chemotypes on lungs are poorly understood. In this study we used bronchoalveolar lavage fluid (BALF) to investigate dose-response (30, 300, 3000 spores/g body weight [BW]) and time-course (3, 6, 24, 48, 96 h post instillation [PI]) relationships in mice to exposure of macrocyclic trichothecene- (JS 58-17) and atranone-producing (JS 58-06) S. chartarum strains, as well as Cladosporium cladosporioides spores. BALF total protein, albumin, pro-inflammatory cytokine (IL-1beta, IL-6, and tumor necrosis factor-alpha [TNF-alpha]), and lactate dehydrogenase (LDH) concentrations showed significant (p < 0.05) fungal species (S. chartarum vs. C. cladosporioides) and strain (58-17 vs. 58-06), spore dose and time dependent changes. The no adverse effect level (NOAEL) due to exposure to spores of JS 58-17 and JS 58-06 was < 30 spores/g BW; for C. cladosporioides it was < 300 spores/g BW. At moderate and high S. chartarum doses, BALF composition reflects differences in strain toxicity while at the lowest dose, BALF composition of either S. chartarum strain were similar. This suggests that at low spore doses, it is spore sequestered factors common to both strains not strain dependent toxins that are contributing to lung disease onset.

PMID: 14718650 [PubMed - indexed for MEDLINE]

80. Toxicol Pathol. 2004 Jan-Feb;32(1):26-34.

Localization of satratoxin-G in Stachybotrys chartarum spores and spore-impacted mouse lung using immunocytochemistry.

Gregory L, Pestka JJ, Dearborn DG, Rand TG.

Department of Biology Saint Mary's University, Halifax, Nova Scotia, B3H 3C3.

Satratoxin-G (SG) is the major macrocyclic trichothecene mycotoxin produced by Stachybotrys chartarum (atra) and has been implicated as a cause of a number of animal and human health problems including pulmonary hemorrhage in infants. However, there is little understanding where this toxin is localized in the spores and mycelial fragments of this species or in the lung impacted by SG-sequestered spores. The purpose of this study was to evaluate the distribution of SG in S. chartarum spores and mycelium in culture, and spore-impacted mouse lung in vivo, using immunocytochemistry. SG was localized predominately in S. chartarum spores with moderate labelling of the phialide-apex walls. Labelling was primarily along the outer plasmalemma surface and in the inner wall layer. Only modest labelling was observed in hyphae. Toxin localization at these sites supports the position that spores contain the highest satratoxin concentrations and that the toxin is constitutively produced. In impacted mouse lung, highest SG labelling was detected in lysosomes, along the inside of the nuclear membrane in nuclear heterochromatin and RER within alveolar macrophages. Alveolar type II cells also showed modest labelling of the nuclear heterochromatin and RER. There was no evidence that the toxin accumulated in the neutrophils, fibroblasts, or other cells associated with the granulomas surrounding spores or mycelial fragments. These observations indicate that SG displays a high degree of cellular specificity with respect to its uptake in mouse lung. They further indicate that the alveolar macrophages play an important role in the sequestration and immobilization of low concentrations of the toxin.

PMID: 14713545 [PubMed - indexed for MEDLINE]

81. Toxicol In Vitro. 2004 Feb;18(1):21-8.

Toxicity and apoptosis induced by the mycotoxins nivalenol, deoxynivalenol and fumonisin B1 in a human erythroleukemia cell line.

Minervini F, Fornelli F, Flynn KM.

Istituto di Scienze delle Produzioni Alimentari, Consiglio Nazionale delle Ricerche, Viale Einaudi, 51, 70125 Bari,

The toxicity of the mycotoxins nivalenol (NIV), deoxynivalenol (DON) and fumonisin B1 (FB1) were studied in the K562 human erythroleukemia cell line using the Trypan Blue, MTT and BrdU uptake analyses of cytotoxicity, cell metabolism and cell proliferation, respectively. Nuclear staining with propidium iodide and DNA analysis by flow cytometry were used to identify apoptosis and cell cycle distribution. By the MTT and BrdU tests, both NIV and DON were significantly more toxic than FB1 by at least one order of magnitude, with ID50s ranging from 0.5 microM for NIV to 70 microM for FB1. The MTT test indicated that NIV was significantly (approximately four times) more toxic than DON. In contrast, the Trypan Blue test did not reveal any effects of mycotoxin exposure suggesting that, at the concentrations tested, NIV, DON and FB1 did not induce cytotoxicity through plasma membrane damage. Cell cycle analysis suggested apoptotic cytotoxicity, revealing 100% cellular debris at the highest concentrations of NIV and DON and approximately 2.9 times more debris than control at the highest FB1 concentration. Morphological evidence of apoptosis was related to the toxicity of the substances, such that the more toxic NIV and DON resulted in more late stage apoptotic events than FB1. This study suggests that human blood cells are sensitive to mycotoxin exposure, that NIV is more toxic than DON which is more toxic than FB1, and that DNA damage and apoptosis rather than plasma membrane damage and necrosis may be responsible for the observed cytotoxicity.

PMID: 14630058 [PubMed - indexed for MEDLINE]

82. Chem Biol Interact. 2003 Oct 25;146(2):105-19.

Potentiation of trichothecene-induced leukocyte cytotoxicity and apoptosis by TNF-alpha and Fas activation.

Uzarski RL, Islam Z, Pestka JJ.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI 48824, USA.

Trichothecene mycotoxins cause immunosuppression by inducing apoptosis in lymphoid tissue. Trichothecene-induced leukocyte apoptosis can be augmented by bacterial lipopolysaccharide (LPS) but the mechanisms involved in this potentiating effect are not completely understood. The objective of this study was to test the hypothesis that the trichothecene deoxynivalenol (DON, vomitoxin) can interact with LPS directly and other mediators or agonists associated with immune/inflammatory responses to induce apoptosis in primary murine leukocyte cultures. Primary leukocyte suspensions were prepared from murine thymus (TH), spleen (SP), bone marrow (BM) and Peyer's patches (PP) and then cultured with DON in the absence or presence of LPS, prostaglandin E2 (PGE2), anti-immunoglobulin (as antigen mimic), dexamethasone, Fas ligand, or TNF-alpha. Cytotoxicity and apoptosis were evaluated by MTT assay and morphologic assays, respectively. DON was found to inhibit LPS-induced proliferation and dexamethasone-induced apoptosis in SP cultures. In contrast, potentiation of DON-induced apoptosis and cytotoxicity was observed in BM cultures treated with anti-Fas and in TH cultures treated with TNF-alpha. When potentiation of DON-induced apoptosis by TNF-alpha was assessed using pharmacological inhibitors, generation of ROS, intracellular Ca2+, p38/SAPK, and caspase-3 activation were found to play roles. Taken together, these data demonstrate that LPS and its downstream mediators can interact with trichothecenes to modulate proliferative, cytotoxic and apoptotic outcomes in leukocytes in a tissue-specific manner.

PMID: 14597125 [PubMed - indexed for MEDLINE]

83. Toxicon. 2003 Jun;41(8):1047-54.

The fates of trichothecene mycotoxins, nivalenol and fusarenon-X, in mice.

Poapolathep A, Sugita-Konishi Y, Doi K, Kumagai S.

Department of Veterinary Pathology, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan.

In order to investigate the comparative fates of nivalenol (NIV) and 4-acetyl derivative of NIV (fusarenon-X, FX) in mice, 3H-FX or 3H-NIV was given p.o. to mice. Radioactivity was excreted mainly via the urine in mice given 3H-FX, but mainly via the feces in mice given 3H-NIV. The plasma radioactivity reached a peak at 30 or 60 min after the administration of 3H-FX or 3H-NIV, respectively. The plasma peak level was 5 times higher, and the area under curve (AUC) was 10 times higher, in 3H-FX-administered than 3H-NIV-administered mice. These findings clearly demonstrate that FX is absorbed from the gastrointestinal tract more rapidly and efficiently than NIV. The HPLC profile of radioactivity of acetonitrile extracts of urine and feces indicated that FX is rapidly metabolized to NIV after being absorbed from the gastrointestinal tract. In vitro incubation of tissue homogenates with 3H-FX demonstrated that the liver and kidney are the organs responsible for the FX-to-NIV conversion. Thus this study demonstrated that the higher oral toxicity of FX than NIV that has been observed in mice and rats is due to the efficient absorption of FX than NIV from the gastrointestinal tract, followed by its rapid conversion to NIV by the liver and kidney.

PMID: 12875880 [PubMed - indexed for MEDLINE]

84. Exp Mol Pathol. 2003 Aug;75(1):74-9.

Development of early apopotosis and changes in lymphocyte subsets in lymphoid organs of mice orally inoculated with nivalenol.

Poapolathep A, Nagata T, Suzuki H, Kumagai S, Doi K.

Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan.

Development of early apoptosis and changes in lymphocyte subsets were examined in lymphoid organs of female BALB/c mice after oral administration of 15 mg/kg b.w. of nivalenol (NIV), the major type B trichothecene mycotoxin, by FACS analysis. Judging from the results of viable cell count and apoptotic cell index, NIV attacked Peyer's patches first and thymus most severely. In thymus, selective damage in CD4(+)CD8(+) cells was observed at 12 and 24 h after inoculation (HAI), following the peak of apoptosis at 9 HAI. CD4(+) cells were clearly suppressed at 3 HAI in Peyer's patches, at and after 9 HAI in mesenteric lymph nodes, and 3 to 12 HAI in spleen, respectively. CD8(+) cells were also suppressed at 24 HAI in mesenteric lymph nodes and at 12 HAI in spleen, respectively. As to changes in B cell subsets, IgG(+) cells significantly decreased from 3 to 12 HAI and all B cell subsets at 24 HAI in mesenteric lymph nodes. In spleen, IgM(+) cells were suppressed at 9 HAI. On the other hand, in Peyer's patches, following clear decrease in the numbers of pan-T and pan-B cells and viable cells at 3 HAI, all B cell subsets, especially IgA(+) cells, showed a significant increase in their numbers at 9 HAI, and the numbers of IgA(+) and IgM(+) cells remained higher values than controls thereafter. Taken together, in the course of recovery from NIV-induced prominent damage in Peyer's patches at 3 HAI, interaction of NIV with Peyer's patches might result in in vivo stimulation of interleukin production at this site and result in increased proliferation and differentiation of IgA-secreting B cells at and after 9 HAI.

PMID: 12834628 [PubMed - indexed for MEDLINE]

85. Toxicol Sci. 2003 Aug;74(2):335-44. Epub 2003 May 28.

Role of double-stranded RNA-activated protein kinase R (PKR) in deoxynivalenol-induced ribotoxic stress response.

Zhou HR, Lau AS, Pestka JJ.

Departments of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan 48824-1224, USA.

Trichothecene mycotoxins and other protein synthesis inhibitors activate mitogen-activated protein kinase (MAPKs) via a mechanism that has been termed the "ribotoxic stress response." MAPKs are believed to mediate the leukocyte apoptosis that is observed following experimental exposure to these chemical agents in vitro and in vivo. The purpose of this research was to test the hypothesis that double-stranded, RNA-activated protein kinase R (PKR) is a critical upstream mediator of the ribotoxic stress response induced by the trichothecene deoxynivalenol (DON) and other translational inhibitors. DON was found to readily induce phosphorylation of JNK 1/2, ERK 1/2, and p38 in the murine macrophage RAW 264.7 cell line, within 5 min of culture addition, in a concentration-dependent fashion. Effects were maximal from 15 to 30 min and lasted up to 6 h. The translational inhibitors anisomycin and emetine also had similar effects when added to cultures at equipotent concentrations to DON. DON rapidly activated PKR within 1 to 5 min, as evidenced by autophosphorylation and by phosphorylation of eukaryotic initiation factor 2alpha (eIF2alpha). Interestingly, the latter effect was associated with rapid degradation of eIF2alpha. Pretreatment of RAW 264.7 cells with two inhibitors of PKR, 2-aminopurine (2-AP) or adenine (Ad), markedly impaired MAPK phosphorylation in RAW 264.7 cells according to the following rank order JNK>p38>ERK. The capacity of DON to induce MAPK phosphorylation was also markedly suppressed in a stable transformant of the human promonocytic U-937 cell line containing an antisense PKR expression vector. This suppression followed a rank order of JNK>p38>ERK in this PKR-deficient cell line when compared to control cells transfected with vector only. Apoptosis induction by DON and two other translational inhibitors, anisomycin and emetine, was almost completely abrogated in PKR-deficient cells. Together, the results indicate that PKR plays a critical upstream role in the ribotoxic stress response inducible by translational inhibitors.

PMID: 12773753 [PubMed - indexed for MEDLINE]

86. Bioorg Med Chem. 2003 Jun 12;11(12):2511-8.

Cancer preventive potential of trichothecenes from Trichothecium roseum.

Konishi K, Iida A, Kaneko M, Tomioka K, Tokuda H, Nishino H, Kumeda Y.

Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.

Bioassay-guided separation of extracts from the culture broth and mycelium of the fungus Trichothecium roseum, aiming at the discovery for cancer preventive agents, resulted in the isolation of three new trichothecene sesquiterpenes, trichothecinols A-C (1-3) together with three known analogues, trichothecin (4), trichodermol (5) and trichothecolone (6). Compounds 1-6 exhibited remarkably potent inhibition against Epstein-Barr virus early antigen (EBV-EA) activation induced by the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA). Further compound 1 strongly inhibited TPA-induced tumor promotion on mouse skin initiated with 7,12-dimethylbenz[a]anthracene (DMBA) in two-stage carcinogenesis tests. These results suggest that compound 1 might be a valuable lead for further evaluation as a cancer preventive agent. In addition to their cancer preventive activity, compound 2 was found to show modest antifungal activity against Crypotcoccus albidus and Saccharomyces cerevisiae.

PMID: 12757719 [PubMed - indexed for MEDLINE]

87. Mycopathologia. 2003;156(2):119-31.

Histological, immunohistochemical and morphometric changes in lung tissue in juvenile mice experimentally exposed to Stachybotrys chartarum spores.

Rand TG, White K, Logan A, Gregory L.

Department of Biology Saint Mary's University, Halifax, Nova Scotia, Canada, B3H 3C3. thomas.rand@STMARYS.CA

Stachybotrys chartarum is an important toxigenic fungus often associated with chronically wet cellulose-based building materials. The purpose of this study was to evaluate some histological, immunohistochemical and morphometric changes in mouse lung tissues exposed intratracheally to either 50 microl of 1.4 x 10(6) S. chartarum spores (< or = 35 ng toxin/kg BW), isosatratoxin-F (35 ng/kg BW), 50 microl of 1.4 x 10(6) Cladosporium cladosporioides spores, or 50 microl saline. Exposure of lung tissues to S. chartarum or C. cladosporioides spores resulted in granuloma formation at the sites of spore impaction. Some of the lung tissues impacted by S. chartarum spores also showed erythrocyte accumulation in the alveolar air space, dilated capillaries engorged with erythrocytes, and hemosiderin accumulation at spore impaction sites, which were features not noted in the C. cladosporioides-spore treated animals. Immunohistochemistry revealed reduced collagen IV distribution in lung granulomas in S. chartarum-treated animals especially at 48 and 72 hr post-exposure compared to that in lungs of mice with C. cladosporioides-spore induced granulomas. Quantitative analysis of pooled S. chartarum and C. cladosporioides spore impacted lungs revealed significant depression (P < 0.05) of alveolar air space from 71.4 +/- 6.1% in untreated animals to 56.04 +/- 6.1% in the S. chartarum- and 60.24 +/- 5.5% in the C. cladosporioides-spore treated animals. It also revealed that alveolus air space in S. chartarum treated animals declined significantly from 63.74 +/- 3.1% at 12 hr post-exposure to 42.94 +/- 7.9% at 72 hr post-exposure and was increased to 54.84 +/- 5.2% at 96 hr post-exposure. Alveolus air space in C. cladosporioides treated animals also decreased significantly from 64.84 +/- 7.1% at 12 hr exposure to 54.94 +/- 5.4% at 48 hr post-exposure and was increased to 64.64 +/- 10.1% at 96 hr post-exposure. It also revealed significant (P < 0.05) alveolar accumulation of erythrocytes from 1.24 +/- 1.4% in the untreated animals to 3.44 +/- 1.5% in the pooled S. chartarum spore treated animals. Erythrocyte abundance in S. chartarum treated animals increased significantly (P < 0.001) from 2.14 +/- 1.7% at 12 hr post-exposure to 5.54 +/- 1.5% at 72 hr and 4.94 +/- 1.4% at 96 hr post-exposure. These results further reveal that exposure to S. chartarum spores elicit tissue responses in vivo significantly different from those associated with exposure to pure trichothecene toxin and to spores of a non-toxigenic fungus.

PMID: 12733633 [PubMed - indexed for MEDLINE]

88. Cell Biol Toxicol. 2003 Feb;19(1):53-68.

Mechanisms involved in the induction of apoptosis by T-2 and HT-2 toxins in HL-60 human promyelocytic leukemia cells.

Holme JA, Morrison E, Samuelsen JT, Wiger R, Låg M, Schwarze PE, Bernhoft A, Refsnes M.

Division of Environmental Medicine, Norwegian Institute of Public Health, Nydalen, Oslo, Norway.

T-2 and HT-2 toxins belong to a group of mycotoxins that are widely encountered as natural contaminants known to elicit toxic responses in hematopoietic cells. In the present study, HL-60 cells were used to characterize the apoptotic effects of T-2 and a major metabolite, HT-2, and to examine the mechanisms involved. Apoptotic cells were identified microscopically by chromatin condensation and nuclear fragmentation, by flow cytometric analysis, and by DNA gel electrophoresis. T-2 and HT-2 induced concentration-dependent apoptosis after 24 h in HL-60 cells, starting at concentrations of 3.1 and 6.25 ng/ml respectively. An increased number of apoptotic cells could be observed 4-6 h after exposure to 12.5 ng/ml of toxin. Little cytotoxicity (plasma membrane damage) was observed even after exposure to concentrations of toxins (25-50 ng/ml) inducing apoptosis in 60-100% of the cells. The apoptotic process was almost completely blocked in the presence of the general caspase inhibitor zVAD.fmk. In contrast, no or only minor effects were observed with the more specific caspase inhibitors DEVD.CHO, IETD.fmk, and DEVD.fmk. As judged by Western blotting, the levels of several procaspases (-3, -7, -8, -9, but not -12) were reduced 3-6 h after exposure to toxin. Substantial increases in the presumed active form(s) of caspase-8 and -9 were observed. Furthermore, poly(ADP-ribose) polymerase (PARP) was already markedly cleaved 3 h after toxin treatment, indicative of active caspase-3 and -7. No or only minor changes in Bcl-2, Bcl-XL and Bax levels were observed. BAPTA-AM and ZnCl2 blocked the degradation of procaspases, the fragmentation of PARP, and the induction of apoptosis. In summary, both T-2 and HT-2 induced apoptosis, with T-2 being somewhat more potent than HT-2. The divalent calcium concentration, [Ca2+], appears to be involved in the activation of several caspases, resulting in DNA fragmentation, chromosomal condensation, and nuclear fragmentation.

PMID: 12661987 [PubMed - indexed for MEDLINE]

89. J Environ Biol. 2002 Jul;23(3):301-20.

Clinical confirmation of trichothecene mycotoxicosis in patient urine.

Croft WA, Jastromski BM, Croft AL, Peters HA.

Environmental Diagnostic Group Inc., Department of Environmental Pathology and Toxicology, 521 Hilltop Drive, Madison, Wisconsin 53711, USA.

The investigations of four Cases involving mold-contaminated buildings and human reaction to exposure, documents tests of extracted urine containing trichothecene mycotoxins confirming exposure and the diagnosis of mycotoxicosis in humans. In each of four Cases, the urine demonstrated antibiotic activity, sulfuric acid charring, and protein release. Urine was extracted using ethyl acetate 40V/60V[EA]. Extracted mycotoxin spotted on (TLC) displayed color and a range of (rf) between 0.2-0.6 using various solvents. Extract was re-suspended using 50% ethanol V/V to inject mycotoxins into weanling female Sprague-Dawley rats. Degeneration and necrosis of the rat's tissue followed. Koch's Postulates conditions were fulfilled by isolation of the causative agent, the trichothecene mycotoxins and the reproduction of disease. Examination of human tissue within the urine extraction group confirms Koch's Postulates and comparative pathology confirms inhalation Mycotoxicosis, with severe necrosis of the central nervous system and severe scarring within the lungs. Extraction of mycotoxins from human patient urine is a very useful confirmatory test to demonstrate exposure and identify mycotoxicosis. Low concentrations (6%) of sodium hypochlorite were ineffective against the activity of trichothecene mycotoxin. The severity or stages of disease directly correlates the level of exposure or poisoning (Patent Pending).

PMID: 12597576 [PubMed - indexed for MEDLINE]

90. Wei Sheng Yan Jiu. 2000 Nov;29(6):387-9.

[Effects of deoxynivalenol on proliferation and tumor necrosis factor-alpha secretion of human peripheral blood mononuclear cells in vitro].

[Article in Chinese]

Wang H, Zhang X, Yang Y, Yan X.

Lab of Experimental Pathology, Hebei Medical Unviersity, Shijiazhuang 050017, China.

Deoxynivalenol (DON) is one of the most common contaminating mycotoxins in food at high risk areas of esophageal carcinoma in China. The effects of DON on proliferation and tumor necrosis factor-alpha (TNF-alpha) secretion of human peripheral blood mononuclear (HPBM) cells in vitro were determined with flow cytometric (FCM) analysis, cell counting, MTT bioassay and ELISA method respectively. FCM analysis revealed that after HPBM were prestimulated with PHA for 48 h, the proliferation indexes(PI) of the cells treated with low concentration of DON (50-500 ng/ml) for 6 h were all dramatically lower than that of normal control (19.80%-26.01% vs 37.84%), while the PI of cells treated with high concentration of DON(1000-2000 ng/ml) for 24 h were higher than that of normal control (35.74%-34.37% vs 22.85%). Cell number counting and MTT bioassay results showed that at the presence of PHA, DON inhibited the proliferation of HPBM. Double antibody sandwich enzyme linked immunosorbent assay (ELISA) showed that the secretion of TNF-alpha in cells treated with DON(500-1000 ng/ml) was significantly lower than that in the control (P < 0.01). The results suggested that DON could either inhibit or stimulate cell proliferation depending on active time, concentration and PHA stimulation. In general, DON mainly inhibited the proliferation of HPBM and decrease TNF-alpha secretion in vitro. Thus, DON might have some negative impacts on human immunological system.

PMID: 12520964 [PubMed - indexed for MEDLINE]

91. J Food Prot. 2002 Dec;65(12):1955-61.

Multiplex polymerase chain reaction assay for the differential detection of trichothecene- and fumonisin-producing species of Fusarium in cornmeal.

Bluhm BH, Flaherty JE, Cousin MA, Woloshuk CP.

Department of Botany and Plant Pathology, Purdue University, 1155 Lilly Hall, West Lafayette, Indiana 47907, USA.

The genus Fusarium comprises a diverse group of fungi including several species that produce mycotoxins in food commodities. In this study, a multiplex polymerase chain reaction (PCR) assay was developed for the group-specific detection of fumonisin-producing and trichothecene-producing species of Fusarium. Primers for genus-level recognition of Fusarium spp. were designed from the internal transcribed spacer regions (ITS1 and ITS2) of rDNA. Primers for group-specific detection were designed from the TRI6 gene involved in trichothecene biosynthesis and the FUM5 gene involved in fumonisin biosynthesis. Primer specificity was determined by testing for cross-reactivity against purified genomic DNA from 43 fungal species representing 14 genera, including 9 Aspergillus spp., 9 Fusarium spp., and 10 Penicillium spp. With purified genomic DNA as a template, genus-specific recognition was observed at 10 pg per reaction; group-specific recognition occurred at 100 pg of template per reaction for the trichothecene producer Fusarium graminearum and at 1 ng of template per reaction for the fumonisin producer Fusarium verticillioides. For the application of the PCR assay, a protocol was developed to isolate fungal DNA from cornmeal. The detection of F. graminearum and its differentiation from F. verticillioides were accomplished prior to visible fungal growth at <10(5) CFU/g of cornmeal. This level of detection is comparable to those of other methods such as enzyme-linked immunosorbent assay, and the assay described here can be used in the food industry's effort to monitor quality and safety.

PMID: 12495016 [PubMed - indexed for MEDLINE]

92. Biomed Environ Sci. 2002 Jun;15(2):145-52.

Effects of sterigmatocystin, deoxynivalenol and aflatoxin G1 on apoptosis of human peripheral blood lymphocytes in vitro.

Sun XM, Zhang XH, Wang HY, Cao WJ, Yan X, Zuo LF, Wang JL, Wang FR.

Department of Experimental Pathology, Hebei Medical University, Shijiazhuang 050017, Hebei, China.

OBJECTIVE: To explore the effects of Sterigmatocystin (ST), Deoxynivalenol (DON) and Aflatoxin G1 (AFG1) on apoptosis of human peripheral blood lymphocytes (HPBLs) in vitro and thus to further elucidate the putative roles of these three mycotoxins on human immunosystem. METHODS: The effects of ST, DON and AFG1 on apoptosis of HPBLs were studied with cell culture, flow cytometric (FCM) DNA analysis and DNA agarose gel electrophoresis. RESULTS: DNA agarose gel electrophoresis results showed the characteristic "ladder" pattern of apoptosis in HPBLs treated with ST, DON and AFG1. Flow cytometric DNA analysis revealed that typical subdiploid peaks of apoptosis in DNA histogram could be seen in all groups treated with the three mycotoxins. Significant time-effect and dose-effect relationships were found between the apoptosis rates and treatment time as well as concentrations of the three mycotoxins. CONCLUSION: ST, DON and AFG1 can induce apoptosis of HPBLs in vitro and may have some negative effects on human immunosystem.

PMID: 12244755 [PubMed - indexed for MEDLINE]

93. Exp Toxicol Pathol. 2002 Feb;53(6):441-6.

Nivalenol--induced apoptosis in thymus, spleen and Peyer's patches of mice.

Poapolathep A, Ohtsuka R, Kiatipattanasakul W, Ishigami N, Nakayama H, Doi K.

Department of Veterinary Pathology, Faculty of Agriculture, The University of Tokyo, Japan.

ICR:CD-1 male mice were orally administered with Nivalenol(NIV) at the dose levels of 5, 10 and 15 mg/kg body weight, and examined at 12, 24 and 48 hours after inoculation (HAI), respectively, to elucidate the process of development of apoptosis in the thymus, spleen and Peyer's patch. There were no signs of clinical disorders and no changes in body and organ weights until 48 HAI except for that the thymus weight significantly decreased at 48 HAI. Immunohistochemically, the number of apoptotic lymphocytes evaluated by in situ detection for fragmented DNA showed a dose-dependent increase at 12 HAI in both the thymus and the Peyer's patch, while it became to increase at 24 HAI in the spleen. Dead lymphocytes in the thymus, spleen and Peyer's patch showed ultrastructural characteristics of apoptosis. Moreover, the DNA ladder was first detected by agarose gel electrophoresis at 12 HAI in the thymus of 15 mg/kg-group. The results clearly indicate that NIV is able to induce apoptosis in the lymphoid tissues of mice.

PMID: 11926285 [PubMed - indexed for MEDLINE]

94. Toxicol Appl Pharmacol. 2002 Apr 1;180(1):43-55.

Endotoxin potentiation of trichothecene-induced lymphocyte apoptosis is mediated by up-regulation of glucocorticoids.

Islam Z, Moon YS, Zhou HR, King LE, Fraker PJ, Pestka JJ.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing, Michigan 48824-1224, USA.

Exposure to bacterial endotoxin (lipopolysaccharide, LPS) is quite common and may increase human susceptibility to chemical-induced tissue injury. The purpose of this study was to identify mechanisms by which LPS potentiates lymphoid tissue depletion in B6C3F1 mice exposed to the common food-borne trichothecene mycotoxin, vomitoxin (VT). As demonstrated by DNA fragmentation and flow cytometric analysis, apoptosis in thymus, Peyer's patches, and bone marrow was marked in mice 12 h after administering Escherichia coli LPS (0.1 mg/kg body wt ip) concurrently with VT (12.5 mg/kg body wt po), whereas apoptosis in control mice or mice treated with either toxin alone was minimal. Based on observed increases in tumor necrosis factor-alpha (TNF-alpha) and interleukin (IL)-6 serum concentrations following LPS and VT cotreatment, the roles of these cytokines in apoptosis potentiation were assessed. Injection with rolipram, an inhibitor of TNF-alpha expression, or use of IL-6 knockout mice was ineffective at impairing thymic apoptosis induction by the toxin cotreatment, suggesting that these cytokines did not mediate LPS potentiation. Toxin cotreatment increased splenic cyclooxygenase-2 mRNA expression, suggesting possible involvement of prostaglandins in apoptosis. However, indomethacin, a broad spectrum inhibitor of cyclooxygenases, failed to block thymus apoptosis. Toxin cotreatment increased serum corticosterone and, furthermore, RU 486, a glucocorticoid receptor antagonist, significantly abrogated apoptosis in thymus, Peyer's patches, and bone marrow following LPS + VT exposure. The results presented herein and the known capacity of glucocorticoids to cause apoptosis indicate that hypothalamic-pituitary-adrenal axis plays a key role in LPS potentiation of trichothecene-induced lymphocyte apoptosis.

(c)2002 Elsevier Science (USA).

PMID: 11922776 [PubMed - indexed for MEDLINE]

95. Food Chem Toxicol. 2002 Apr;40(4):479-86.

Effect of T-2 toxin on in vivo lipid peroxidation and vitamin E status in mice.

Vilà B, Jaradat ZW, Marquardt RR, Frohlich AA.

Department of Animal Science, University of Manitoba, Winnipeg, R3T 2N2, Manitoba, Canada.

The effects of an acute administration of T-2 toxin on vitamin E status and the corresponding degree of lipid peroxidation, as determined by the plasma and organ content of malondialdehyde (MDA), was studied in mice. The effects of T-2 toxin administration on the body weight and weights of liver, spleen and thymus were also assessed. T-2 toxin was administered in doses ranging from 1 to 6.25 mg/kg body weight, depending on the experiment, while the dietary content of vitamin E ranged from near 0 to 5000 IU/kg. There was a significant decrease in vitamin E content of plasma after the administration of the toxin with the concentrations remaining low for periods as long as 48-72 h. MDA content of liver increased significantly after 24-48 h of toxin administration in contrast to the controls. However, MDA levels returned to the control range after 72 h. The concentrations of MDA in liver were inversely related to the vitamin E content of the diet, and were always higher for the toxin-treated animals (significant linear regression between MDA content of liver and the log10 of vitamin E content of the diet). Weights of spleen and thymus decreased after T-2 toxin administration; however, the weight of liver either increased or did not change in the different experiments. In conclusion, T-2 toxin treatment of mice increased lipid peroxidation in the liver as measured by MDA production. This process was maximal after 48 h of T-2 challenge, and decreased thereafter. Plasma alpha-tocopherol levels decreased as soon as 6 h after the toxin challenge, while MDA did not increase until there was a severe depletion of vitamin E. These changes were accompanied by decrease in weight of spleen and thymus.

PMID: 11893407 [PubMed - indexed for MEDLINE]

96. J Nutr. 2002 Feb;132(2):261-9.

Dietary fish oil suppresses experimental immunoglobulin a nephropathy in mice.

Pestka JJ, Zhou HR, Jia Q, Timmer AM.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI 48824, USA.

Dietary fish oil (FO) supplementation reportedly retards the progression of renal disease in patients with immunoglobulin (Ig)A nephropathy (IgAN), the most common glomerulonephritis worldwide. Using an experimental mouse model in which early immunopathological hallmarks of IgAN are induced by the mycotoxin vomitoxin (VT), the ameliorative effects of FO ingestion on this disease were evaluated in two studies. In Study 1, the capacity of VT to induce IgAN was evaluated in mice fed for 12 wk AIN-76A diets containing 50 g/kg corn oil (CO), 50 g/kg CO plus 9 mg/kg tert butylhydroquinone (TBHQ), or 5 g/kg CO plus 45 g/kg menhaden FO that contained 200 mg/kg TBHQ. Serum IgA, serum IgA immune complexes and kidney mesangial IgA deposition were greater in mice fed VT + CO compared with the CO control group, whereas all three variables were significantly attenuated in mice fed VT + FO. Although TBHQ also had attenuating effects, these were significantly less than those for the VT + FO group. In Study 2, the effects of feeding modified AIN 93G diets containing either 70 g/kg CO or 10 g/kg CO plus 60 g/kg FO for 20 wk on VT-induced IgAN were compared. Again, consumption of FO attenuated all three immunopathological variables. In addition, spleen cell cultures from the VT + FO group produced markedly less IgA than those cultures from mice fed VT + CO. Taken together, the results suggested that diets containing FO may impair early immunopathogenesis in VT-induced IgAN and that this was not totally dependent on the presence of the antioxidant TBHQ.

PMID: 11823588 [PubMed - indexed for MEDLINE]

97. Am J Ther. 2002 Jan-Feb;9(1):5-14.

Biological and chemical agents: a brief synopsis.

Rosenbloom M, Leikin JB, Vogel SN, Chaudry ZA.

Northwestern University School of Medicine, Chicago, IL, USA.

The objective of this article is to provide a concise overview of the most likely biological and chemical agents that could be used as biochemical weapons. The diagnosis, pathology, prevention, decontamination, treatment, and disposition of these biological and chemical agents are presented in a tabular format for quick reference purposes. The information provided outlines the bare essentials needed to deal with any emergency or catastrophic event involving these agents.

PMID: 11782813 [PubMed - indexed for MEDLINE]

98. Arch Environ Health. 2001 Sep-Oct;56(5):413-7.

Possible sources of sick building syndrome in a Tennessee middle school.

Scheel CM, Rosing WC, Farone AL.

Department of Biology, Middle Tennessee State University, Murfreesboro 37132, USA.

Sick Building Syndrome has been reported with increasing frequency during recent years. Buildings that have sustained water damage harbor various molds, some of which may be toxic. Students and staff at Central Middle School in Murfreesboro, Tennessee, reported symptoms similar to those associated with Sick Building Syndrome. Upon investigation, investigators noted that a black fungal growth occurred throughout the building on wet cellulose ceiling tiles. Fungal growth of this type is consistent with the genus Stachybotrys. Stachybotrys spores contain macrocyclic trichothecenes, which may cause harm when inhaled or ingested. Bulk sampling of the black mold was initiated, and the samples were cultured in a moist chamber. Testing of the samples confirmed the presence of Stachybotrys spp., a finding that implies that air sampling procedures should ensue. Professional remediation of this potentially hazardous fungal contaminant is therefore recommended.

PMID: 11777022 [PubMed - indexed for MEDLINE]

99. Exp Toxicol Pathol. 2001 Sep;53(4):309-15.

Development of apoptosis and changes in lymphocyte subsets in thymus, mesenteric lymph nodes and Peyer's patches of mice orally inoculated with T-2 toxin.

Nagata T, Suzuki H, Ishigami N, Shinozuka J, Uetsuka K, Nakayama H, Doi K.

Department of Veterinary Pathology, Faculty of Agriculture, The University of Tokyo, Japan.

Development of apoptosis and changes in lymphocyte subsets were examined mainly by flow cytometer in thymus, mesenteric lymph nodes and Peyer's patches of mice up to 24 hours after oral inoculation with T-2 toxin (10 mg/kg). T-2 toxin attacked Peyer's patches first, then mesenteric lymph nodes, and finally thymus in relation to the course of enteric absorption of orally inoculated T-2 toxin. The degree of lymphocyte apoptosis was prominent in the thymus, moderate in the Peyer's patches, and somewhat mild in the mesenteric lymph nodes, suggesting the difference in lymphocyte population susceptible to T-2 toxin. As to the changes in lymphocyte subsets, CD4+ CD8+ T cells were most sensitive to T-2 toxin, and CD4+ CD8- T cells were more severely depressed than CD4- CD8+ T cells in the thymus. In the mesenteric lymph nodes, CD3+ cells was more clearly affected than CD19+ cells, and the numbers of CD4+ and CD8+ cells were similarly decreased. In the Peyer's patches, the numbers of CD3+, CD 19+, CD4+ and CD8+ cells were unexceptionally decreased. In addition, among IgM+, IgG+ and IgA+ B cells, the number of IA+ B cells which are more important in the mucosal immunity was most severely affected.

PMID: 11665856 [PubMed - indexed for MEDLINE]

100. Exp Toxicol Pathol. 2001 Sep;53(4):271-4.

Kinetics of cytokines mRnas expression in the dorsal skin of WBN/ILA-Ht rats following topical application of T-2 toxin.

Albarenque SM, Suzuki K, Nakayama H, Doi K.

Departament of Veterinary Pathology, Faculty of Agriculture, The University of Tokyo, Japan.

The kinetics of cytokines mRNAs expression was examined in the dorsal skin of Wistar-derived hypotrichotic WBN/ILA-Ht rats topically applied with T-2 toxin. After the application of 10 microl (0.5 microg/microl) of T-2 toxin solution, the total mRNA was obtained from skin biopsies at 3, 6, 12 and 24 hours after treatment (HAT). Reverse transcription-polymerase chain reaction (RT-PCR) was carried out with pairs of oligonucleotide primers corresponding to the cDNA sequences of rat TNF-alpha, IL-1 alpha, IL-1beta, IL-6 and IL-10 cytokines. The level of TNF-alpha mRNA showed marked elevation at 3HAT and decreased toward 24HAT, but it remained significantly higher level even at 24HAT. In addition, the level of IL- 1beta mRNA expression showed a sligth but significant elevation at 3 and 24HAT. On the other hand, no significant differences were observed in other cytokines mRNAs expression between T-2 toxin-treated and control groups througth the observation period. Together with our previous report describing the sequence of epidermal cell apoptosis (Albarenque et al. 1999), the present results suggest that the elevation of TNF-alpha mRNA expression may play an important role in T-2 toxin-induced epidermal cell apoptosis.

PMID: 11665851 [PubMed - indexed for MEDLINE]

101. Exp Toxicol Pathol. 2001 Feb;52(6):553-6.

Kinetics of apoptosis-related genes mRNA expression in the dorsal skin of hypotrichotic WBN/ILA-ht rats after topical application of T-2 toxin.

Albarenque SM, Suzuki K, Shinozuka J, Nakayama H, Doi K.

Department of Veterinary Pathology, Faculty of Agriculture, The University of Tokyo, Japan.

The expression of apoptosis-related genes mRNAs was examined in the dorsal skin of hypotrichotic WBN/ILA-Ht rats topically applied with T-2 toxin (10 microl of 0.5 microg/microl solution). The total mRNA was obtained from skin biopsy samples from each rat at 3, 6, 12 and 24 hours after T-2 toxin treatment (HAT), and RT-PCR was carried out with pairs of oligonucleotide primers corresponding to the cDNA sequences of rat p53, bcl-2, c-ki-ras, c-fos and c-jun oncogenes. The expression of c-fos mRNA markedly increased at 3 HAT, peaked at 6 HAT, and greatly decreased at 12 HAT. However it maintained a higher level, compared with the control level, even at 24 HAT. Although not prominent, the expression of c-jun mRNA also showed significant elevation from 3 to 12 HAT. On the other hand, there were no changes in the expression of p53, bcl-2 and c-ki-ras mRNAs throughout the observation period. Judging from the present results and our previous report that epidermal cells developed apoptosis at 12 HAT (Histol Histopathol 1999; 14: 337-342), the induction of c-fos and perhaps of c-jun mRNAs may be associated with T-2 toxin-induced epidermal cell apoptosis.

PMID: 11256758 [PubMed - indexed for MEDLINE]

102. Exp Toxicol Pathol. 2001 Feb;52(6):493-501.

Apoptosis in mouse fetuses from dams exposed to T-2 toxin at different days of gestation.

Ishigami N, Shinozuka J, Katayama K, Nakayama H, Doi K.

Department of Veterinary Pathology, Faculty of Agriculture, The University of Tokyo, Japan. aa77/

T-2 toxin (2 mg/kg b.w.) was orally inoculated to pregnant mice at gestational day (GD) 8.5, 9.5, 10.5, 11.5, 12.5, 13.5, 14.5, 15.5 and GD 16.5, respectively, and the fetuses were examined 24 hours later. The number and region of pyknotic or karyorrhectic cells varied according to inoculation date. In the GD 13.5-subgroup, a moderate to high number of pyknotic or karyorrhectic neuronal cells were observed in the central nervous system, peri-ventricular zone to subventricular zone, and pyknosis or karyorrhexis were also observed in a small number of chondroblasts and chondrocytes. In the GD 16.5-subgroup, a moderate to high number of pyknotic or karyorrhectic cells were observed in the thymus and renal subcapsular parenchyma. The nuclei of these pyknotic or karyorrhectic cells were strongly stained by the terminal deoxy nucleotidyl transferase (TdT)-mediated dUTP-digoxigenin nick end labeling method widely used for the in situ detection of apoptotic nuclei. In addition, a few fetuses from dams which were given T-2 toxin at GD 13.5 or GD 14.5 and killed at GD 17.5 showed skeletal abnormalities such as wavy ribs and short scapula. From the present findings and the well known fact that T-2 toxin readily crosses the rat placenta, it seems that T-2 toxin-induced apoptosis in the developing mouse fetuses might be a direct effect of T-2 toxin on fetuses.

PMID: 11256751 [PubMed - indexed for MEDLINE]

103. Vopr Pitan. 2000;69(5):24-7.

[Effects of bioflavonoids on the toxicity of T-toxin in rats. A morphological study].

[Article in Russian]

Pozdniakov AL, Kravchenko LV, Avren'eva LI, Kazenkina NB.

Subacute toxicity of T-2 toxin in rats was characterized by a primary defeat of liver, thymus, spleen and intraorgan arteries. In 75% of animals found out increase of the size and adipose infiltration of a liver, in all animals--reduction of the size of thymus (sharp) and spleen (moderate) and pronounced hypoplasia of lymphoid tissue. In the majority of rats vacuolation of cytoplasma of smooth-muscular walls of coronary and intrarenal arteries was revealed. In animals received T-2 toxin against a background of a diet with addition a flour from seeds of milk thistle with high contents of flavonoids, described morphological changes were expressed to a lesser degree and were observed less often. Moderate periportal adipose infiltration of a liver was revealed in 30% of animals, occupancy by cells of lymphoid tissue increased, the quantity and sizes of vacuoles in walls of vessels decreased.

PMID: 11247161 [PubMed - indexed for MEDLINE]

104. Exp Toxicol Pathol. 2000 Aug;52(4):297-301.

Kinetics and distribution of transforming growth factor (TGF)-beta 1 mRNA in the dorsal skin of hypotrichotic WBN/ILA-Ht rats following topical application of T-2 toxin.

Albarenque SM, Shinozuka J, Suzuki K, Nakayama H, Doi K.

Department of Veterinary Pathology, Faculty of Agriculture, The University of Tokyo, Japan.

Depression of basal cell proliferating activity and subsequent induction of basal cell apoptosis in the epidermis and infiltration of inflammatory cells including mast cells in the dermis were observed in the dorsal skin of hypotrichotic WBN/ILA-Ht rats following the topical application of T-2 toxin in our previous study (ALBARENQUE et al. 1999). In the present study, kinetics of TGF-beta 1 mRNA was investigated using the same experimental system. The level of TGF-beta 1 mRNA of the whole skin tissue measured by competitive RT-PCR method showed a slight elevation from 6 to 12 hours after treatment (HAT) and reached the significantly higher level at 24HAT compared with the control skin. The increase in signals of TGF-beta 1 mRNA detected by in situ hybridization method started at 3HAT in the epidermis and progressed thereafter both in the epidermis and in the dermis. These results suggest that the elevated level of TGF-beta 1 mRNA may have a close relation to the induction of epidermal basal cell apoptosis as well as to the intradermal infiltration of mast cells and fibroblasts following the topical application of T-2 toxin.

PMID: 10987180 [PubMed - indexed for MEDLINE]

105. Cell Biol Toxicol. 1999;15(4):203-15.

Effects of four trichothecene mycotoxins on activation marker expression and cell proliferation of human lymphocytes in culture.

Johannisson A, Bjökhag B, Hansson W, Gadhasson IL, Thuvander A.

Department of Pathology, Faculty of Veterinary Medicine, Swedish University of Agricultural Sciences, Uppsala.

Four trichothecene mycotoxins--the type A trichothecenes T2-toxin and diacetoxyscirpenol and the type B trichothecenes nivalenol and deoxynivalenol--were studied. The effects of these mycotoxins on the expression of the sequentially expressed activation markers CD69, CD25, and CD71 and on proliferation of human lymphocytes were studied in culture with a duration of up to 72 h. All the examined toxins affected activation marker expression in a similar way. After 6 h, the CD69 expression was lower in exposed cultures compared to controls. After 24 and 48 h of exposure, an increased frequency of cells expressing CD69 was found in exposed cultures, indicating a delay in downregulation of CD69 expression. Stimulation of CD25 expression was observed for doses below the IC50 value, while suppression was found for higher doses. The pattern was different from that detected for CD69 expression, in that an increased expression of CD25 never occurred after exposure to the highest concentration of the toxin, and in that no stimulatory effects were found after 48 h of exposure, indicating that the response was inhibited and not delayed. The effects of toxin exposure on CD71 expression were in many respects similar to the effects on CD25 expression. We conclude that the trichothecene mycotoxins investigated in this study inhibited the cell cycle in a similar way and exert their main antiproliferative action rather early in the cell cycle, before or in conjunction with CD25 expression.

PMID: 10696820 [PubMed - indexed for MEDLINE]

106. Toxicol Sci. 2000 Feb;53(2):253-63.

Lipopolysaccharide and the trichothecene vomitoxin (deoxynivalenol) synergistically induce apoptosis in murine lymphoid organs.

Zhou HR, Harkema JR, Hotchkiss JA, Yan D, Roth RA, Pestka JJ.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing 48824-1224, USA.

Human exposure to Gram-negative bacterial lipopolysaccharide (LPS) is common and may have an important influence on chemical toxicity. LPS has been shown previously to enhance synergistically the toxicity of trichothecene mycotoxins. Because either of these toxin groups alone characteristically target lymphoid organs at high doses, we evaluated the effects of coexposure to subthreshold doses of Salmonella typhimurium LPS and vomitoxin (VT) administered by intraperitoneal injection and oral gavage of B6C3F1 mice, respectively, on apoptosis in lymphoid tissues after 12-h exposure. The capacity of LPS (0.5 mg/kg body weight) and VT (25 mg/kg body weight) to act synergistically in causing apoptosis in thymus, spleen, and Peyer's patches was suggested by increased internucleosomal DNA fragmentation in whole cell lysates as determined by gel electrophoresis. Following terminal deoxynucleotidyl transferase (TdT)-mediated fluorescein-dUTP nick end-labeling (TUNEL) of tissue sections, a dramatic enhancement of fluorescence intensity indicative of apoptosis was observed in thymus, spleen, Peyer's patches, and bone marrow from coexposed animals as compared to those given the agents alone. Evaluation of hematoxylin and eosin-stained tissue sections of treatment mice revealed the characteristic features of lymphocyte apoptosis, including marked condensation of nuclear chromatin, fragmentation of nuclei, and formation of apoptotic bodies in tissues from mice. Combined treatment with VT (25 mg/kg body weight) and LPS (0.5 mg/kg body weight) significantly increased (p<0.05) the amount of apoptotic thymic and splenic tissue as compared to the expected additive responses of mice receiving either toxin alone. When apoptosis was examined in cell suspensions of thymus, spleen, Peyer's patches, and bone marrow by flow cytometry in conjunction with propidium iodide staining, the percentage of apoptotic cells was significantly increased (p<0.05) in cotreatment groups as compared to the additive responses to LPS and VT given alone. The results provide qualitative and quantitative evidence for the hypothesis that LPS exposure markedly amplifies the toxicity of trichothecenes and that the immune system is a primary target for these interactive effects.

PMID: 10696773 [PubMed - indexed for MEDLINE]

107. Appl Environ Microbiol. 1999 Aug;65(8):3279-86.

Identification of mimotope peptides which bind to the mycotoxin deoxynivalenol-specific monoclonal antibody.

Yuan Q, Pestka JJ, Hespenheide BM, Kuhn LA, Linz JE, Hart LP.

Departments of Botany and Plant Pathology, Michigan State University, East Lansing, Michigan 48824, USA.

Monoclonal antibody 6F5 (mAb 6F5), which recognizes the mycotoxin deoxynivalenol (DON) (vomitoxin), was used to select for peptides that mimic the mycotoxin by employing a library of filamentous phages that have random 7-mer peptides on their surfaces. Two phage clones selected from the random peptide phage-displayed library coded for the amino acid sequences SWGPFPF and SWGPLPF. These clones were designated DONPEP.2 and DONPEP.12, respectively. The results of a competitive enzyme-linked immunosorbent assay (ELISA) suggested that the two phage displayed peptides bound to mAb 6F5 specifically at the DON binding site. The amino acid sequence of DONPEP.2 plus a structurally flexible linker at the C terminus (SWGPFPFGGGSC) was synthesized and tested to determine its ability to bind to mAb 6F5. This synthetic peptide (designated peptide C430) and DON competed with each other for mAb 6F5 binding. When translationally fused with bacterial alkaline phosphatase, DONPEP.2 bound specifically to mAb 6F5, while the fusion protein retained alkaline phosphatase activity. The potential of using DONPEP.2 as an immunochemical reagent in a DON immunoassay was evaluated with a DON-spiked wheat extract. When peptide C430 was conjugated to bovine serum albumin, it elicited antibody specific to peptide C430 but not to DON in both mice and rabbits. In an in vitro translation system containing rabbit reticulocyte lysate, synthetic peptide C430 did not inhibit protein synthesis but did show antagonism toward DON-induced protein synthesis inhibition. These data suggest that the peptides selected in this study bind to mAb 6F5 and that peptide C430 binds to ribosomes at the same sites as DON.

PMCID: PMC91492 PMID: 10427007 [PubMed - indexed for MEDLINE]

108. Histol Histopathol. 1999 Jul;14(3):729-33.

Apoptosis in the developing mouse embryos from T-2 toxin-inoculated dams.

Ishigami N, Shinozuka J, Katayama K, Uetsuka K, Nakayama H, Doi K.

Department of Veterinary Pathology, Faculty of Agriculture, University of Tokyo, Japan.

T-2 toxin (3 mg/kg b.w.) was orally inoculated to pregnant mice at 11 days of gestation to examine the effect of T-2 toxin on the developing embryos. At 24 hours after T-2 toxin-inoculation, moderate pyknosis or karyorrhexis was generally observed in some layers of the central nervous system, caudal sclerotomic segment, caudal region of the tongue to pharyngeal- to laryngeal-mesenchyma, trachea and facial mesenchyma. These pyknotic or karyorrhectic nuclei were strongly stained by the modified TUNEL method widely used for the in situ detection of apoptotic nuclei and also showed ultrastructural changes characteristic for apoptosis. This is the first report of mycotoxin-induced apoptosis in embryos.

PMID: 10425541 [PubMed - indexed for MEDLINE]

109. J Toxicol Environ Health A. 1999 May 28;57(2):115-36.

Amplified proinflammatory cytokine expression and toxicity in mice coexposed to lipopolysaccharide and the trichothecene vomitoxin (deoxynivalenol).

Zhou HR, Harkema JR, Yan D, Pestka JJ.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing 48824, USA.

A single oral exposure to the trichothecene vomitoxin (VT) has been previously shown in the mouse to increase splenic mRNA levels for several cytokines in as little as 2 h. Since one underlying mechanism for these effects likely involves superinduction of transiently expressed cytokine genes, VT may also potentially amplify cytokine responses to inflammatory stimuli. To test this possibility, the effects of oral VT exposure on tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and IL-1beta expression were measured in mice that were intraperitoneally injected with lipopolysaccharide (LPS), a prototypic inflammatory agent. As anticipated, VT alone at 1, 5, and 25 mg/kg body weight increased splenic mRNA expression of all three cytokines after 3 h in a dose-response fashion. LPS injection at 1 and 5 mg/kg body weight also induced proinflammatory cytokine mRNA expression. There was a synergistic increase in TNF-alpha splenic mRNA levels in mice treated with both VT and LPS as compared to mice treated with either toxin alone, whereas the effects were additive for IL-6 and IL-1beta mRNA expression. When relative mRNA levels were examined over a 12-h period in mice given LPS (1 mg/kg) and/or VT (5 mg/kg), significant enhancement was observed up to 6, 12, and 3 h for TNF-alpha, IL-6, and IL-1beta, respectively. When plasma cytokine concentrations were measured, TNF-alpha was found to peak at 1 h and was significantly increased at 1, 3, and 6 h if mice were given LPS and VT, whereas LPS or VT alone caused much smaller increases in plasma TNF-alpha Plasma IL-6 peaked at 3 h in LPS, VT, and LPS/VT groups, with the combined toxin group exhibiting additive effects. Plasma IL-1beta was not detectable. The potential for VT and LPS to enhance toxicity was examined in a subsequent study. Mortality was not observed up to 72 h in mice exposed to a single oral dose of VT at 25 mg/kg body weight or to an intraperitoneal dose of LPS at 1 or 5 mg/kg body weight; however, all mice receiving VT and either LPS dose became moribund in less than 40 h. The principal histologic lesions in the moribund mice treated with VT and LPS were marked cell death and loss in thymus, Peyer's patches, spleen, and bone marrow. In all of these lymphoid tissues, treatment-induced cell death had characteristic histologic features of apoptosis causing lymphoid atrophy. These results suggest that LPS exposure may markedly increase the toxicity of trichothecenes and that the immune system was a primary target of these interactive effects.

PMID: 10344227 [PubMed - indexed for MEDLINE]

110. Histol Histopathol. 1999 Apr;14(2):337-42.

T-2 toxin-induced acute skin lesions in Wistar-derived hypotrichotic WBN/ILA-Ht rats.

Albarenque SM, Shinozuka J, Iwamoto S, Nakayama H, Doi K.

Department of Veterinary Pathology, Faculty of Agriculture, University of Tokyo, Japan.

Acute lesions in the dorsal skin topically applied with T-2 toxin (10 microliters of 0.5 mg/ml-solution to 1 cm2) were examined in Wistar-derived hypotrichotic WBN/ILA-Ht rats up to 24 hours after treatment (24HAT). In the epidermis, depression of basal cell proliferating activity was detected at 3HAT by immunostaining for proliferating cell nuclear antigen (PCNA), and the percentage of PCNA-positive basal cells decreased thereafter. At 12HAT, in addition to intracytoplasmic edema of spinous cells, acidophilic degeneration of basal cells characterized by shrinkage of cell body with acidophilic cytoplasm and pyknotic or karyorrhectic nuclei became prominent. Most of these nuclei were positive for TUNEL which is a widely used immunostaining for the in situ detection of fragmented DNA, i.e. apoptosis, and the percentage of TUNEL-positive basal cells increased thereafter. The nuclei of these basal cells also showed ultrastructural changes characteristic for apoptosis. On the other hand, in the dermis, infiltration of inflammatory cells including mast cells started at 3HAT and increased thereafter. In addition, capillary and small vessel endothelial degeneration developed at 6HAT and progressed thereafter. These results suggest that T-2 toxin directly affects the epidermis and produces apoptosis in basal cells.

PMID: 10212794 [PubMed - indexed for MEDLINE]

111. Food Chem Toxicol. 1998 Dec;36(12):1095-106.

Experimental murine IgA nephropathy following passive administration of vomitoxin-induced IgA monoclonal antibodies.

Yan D, Rumbeiha WK, Pestka JJ.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing 48824, USA.

Oral exposure of mice to vomitoxin (VT) induces elevated levels of serum IgA, circulating IgA immune complexes (IgA-IC), mesangial IgA deposition and haematuria, which all mimic the clinical signs of human IgA nephropathy (IgAN). To further assess the effects of VT-induced IgA in the murine model, B6C3F1 and BALB/C mice were injected intraperitoneally with affinity-purified monoclonal IgA derived from Peyer's patch hybridomas of VT-exposed mice. In B6C3F1 mice, serum IgA, IgM and IgA-IC levels were increased two- to fivefold in treatment groups after 4 and 6 wk compared with controls, whereas increases in serum IgG as high as 18-fold were observed. Urinary erythrocyte counts were also significantly elevated in treatment groups after 2, 4 and 6 wk compared with controls. Concurrent increases in IgA and IgG complexes containing casein, the dietary protein source, occurred in treatment mice. Mesangial IgA, IgG, IgM and C3 deposition were significantly increased in all treatment mice after 6 wk. Electron-dense deposits occurred in the glomeruli of IgA-injected mice after 6 wk. All the above parameters were similarly affected in BALB/C mice. Injection of IgA-secreting hybridoma cells into BALB/C mice increased serum IgA, IgA-IC and IgG levels as well as elevated mesangial IgA, IgG and C3 deposition and haematuria after 2-3 weeks compared with controls. In total, these data indicate that passive administration of VT-induced IgAs can induce the hallmarks of IgA nephropathy. Casein, an antigen found in the diet used for these mice, appeared to form IC with IgA or IgG and these IC may participate in the pathogenesis of this nephropathy.

PMID: 9862652 [PubMed - indexed for MEDLINE]

112. Virchows Arch. 1998 Nov;433(5):443-7.

The process of ultrastructural changes from nuclei to apoptotic body.

Ihara T, Yamamoto T, Sugamata M, Okumura H, Ueno Y.

Department of Pathology, Tochigi Institute of Clinical Pathology, Japan.

There have been many reports on the formation of apoptotic bodies, but little is known about the cellular pathological processes and the morphological changes involved. We induced apoptotic cell death by administering nivalenol (NIV), a trichothecene mycotoxin produced by Fusarium species, and investigated the ultrastructural process of formation of apoptotic bodies. The thymus was examined by electron microscopy 6, 12, and 18 h after administration. Apoptotic cell death was induced in the thymus of NIV-treated mice. The nuclei became invaginated and pinched off to give fragments, and crescent-shaped spaces (CSS) were found around the nuclear envelopes of these cells at quite an early stage. In some of these spaces, myelin figures were observed. We divided the process of formation into four stages and characterized each of them. These are easily recognized in morphological stages and are also useful for clarifying the apoptotic mechanism.

PMID: 9849859 [PubMed - indexed for MEDLINE]

113. Toxicol Pathol. 1998 Sep-Oct;26(5):674-81.

T-2 toxin-induced apoptosis in hematopoietic tissues of mice.

Shinozuka J, Suzuki M, Noguchi N, Sugimoto T, Uetsuka K, Nakayama H, Doi K.

Department of Veterinary Pathology, Faculty of Agriculture, University of Tokyo, Japan.

We examined T-2 toxin-induced lesions in the bone marrow and splenic red pulp as many as 48 hr after oral inoculation with 10 mg/kg body weight of T-2 toxin in female ICR:CD-1 mice. Histopathologically, the bone marrow and splenic red pulp showed a significant hypocellularity. In the bone marrow, the number of myelocytes significantly decreased due to the loss of immature granulocytes, erythroblasts, and lymphocytes. The nuclei of the remaining cells showing pyknosis or karyorrhexis were positively stained by the TdT-mediated dUTP nick end labeling (TUNEL) method, and these TUNEL-positive cells showed ultrastructural characteristics of apoptosis. With agarose gel electrophoresis, DNA ladders were clearly detected in bone marrow samples. The number of TUNEL-positive cells in splenic red pulp increased earlier than it did in the splenic white pulp. Thus, T-2 toxin induced-lesions in the hematopoietic tissues and in the lymphoid tissues were brought about by apoptosis of component cells. We believe that damage to the hematopoietic microenvironment may also play an indirect role in the induction of apoptosis in the bone marrow.

PMID: 9789955 [PubMed - indexed for MEDLINE]

114. J Toxicol Sci. 1998 Jul;23 Suppl 2:148-54.

Fine structural changes and apoptotic cell death by T-2 mycotoxin.

Sugamata M, Hattori T, Ihara T, Okumura H, Yoshino N, Ueno Y.

Department of Pathology, Institute of Tochigi Clinical Pathology, Inc., Japan.

PMID: 9760453 [PubMed - indexed for MEDLINE]

115. Toxicology. 1998 May 15;127(1-3):195-206.

Induction of apoptosis with fusarenon-X in mouse thymocytes.

Miura K, Nakajima Y, Yamanaka N, Terao K, Shibato T, Ishino S.

Feed Safety Research Division, National Institute of Animal Health, Tsukuba, Ibaraki, Japan.

The effects of fusarenon-X (12,13-epoxytrichothecene; FX) on mouse thymus and T-cell subpopulations were studied. In mice that received three intraperitoneal injections of FX, the thymus showed severe atrophy, the thymic cortex almost completely disappeared, and the total number of thymocytes decreased to 2.2% of that of normal mice. CD4+ CD8+ thymocytes were almost completely depleted by this treatment while CD4+ CD8-, CD4- CD8+ and CD4- CD8- thymocytes were not reduced to such an extent, suggesting that selective damage in CD4+ CD8+ thymocytes was induced by FX. In spleen, CD4+ or CD8+ lymphocytes and CD4- CD8- non-T cells remained unchanged. Next, the mode of damage in thymocytes was investigated by a single injection with FX. The lymphocyte nuclei were fragmented and positive for TUNEL (TdT-mediated dUTP nick-end labeling) staining in the thymic cortex 20 h after FX injection. By electron microscopy, apoptotic lymphocytes with condensed nuclei and stroma cells ingesting many nuclear fragments were frequently observed in the thymic cortex. Internucleosomal DNA fragmentation was apparent in the thymocytes treated with FX both in vivo and in vitro. Thus, we demonstrated that the trichothecene mycotoxin FX is a new cause of apoptosis in CD4+ CD8+ thymocytes of mice besides the other factors that cause similar effects.

PMID: 9699806 [PubMed - indexed for MEDLINE]

116. J Exp Clin Cancer Res. 1998 Mar;17(1):33-40.

T-2 toxin affects proliferation of three different neoplastic cell lines.

Juranić Z, Stojiljković MP, Bocarov-Stancić A, Kilibarda V, Milovanović SR, Juranić I, Bijelogrlić S, Vuletić N, Radulović S.

Institute of Oncology and Radiology of Serbia, Belgrade, Yugoslavia.

The antiproliferative effect of T-2 toxin (T-2) towards mouse melanoma B16 cells, human myelogenous leukemia K562 cells, and human cervix carcinoma, HeLa cells, was studied. For the first four days of T-2 presence B16 cell survival was decreased in dose dependent fashion. However, cell survival after eleven days T-2 action may be dual: some stimulation of cell growth that was direct function of the number of seeded cells per well was observed and cell survival (for the highest number of seeded cells) six times greater than control, was noticed at 20 nM T-2 toxin concentration. A smaller cell growth stimulation (cell survival more than 3 times higher than control) was observed with a lower cell number seeded per well. Nevertheless, by eleventh day concentrations of T-2 higher than 35 nM completely inhibited B16 cell proliferation. The same trend was noticed for T-2 action towards K562 cells. Treatment of HeLa cells with various T-2 concentrations led to a marked inhibition of cell survival that was more pronounced at the end of 44th or 72nd hour, than after the 20th hour of agent's action. ICs50 values obtained in the present work, suggest that B16 cells were the most sensitive to T-2 antiproliferative action, while HeLa cells were the most resistant. When PBMC were cultured with HeLa cells the antagonism against various T-2 concentrations was observed; cell survival determined after 44, or 72 hours of cells incubation, was less decreased compared to cultures treated with T-2, or with PBMC only. In addition, it was shown that T-2 and cis-DDP had an antagonist effect on HeLa cells survival.

PMID: 9646231 [PubMed - indexed for MEDLINE]

117. Toxicol Appl Pharmacol. 1998 Feb;148(2):205-14.

T-2 toxin induces thymic apoptosis in vivo in mice.

Islam Z, Nagase M, Yoshizawa T, Yamauchi K, Sakato N.

Faculty of Agriculture, Kagawa University, Miki-cho, Kita-gun, Kagawa, 761-0795, Japan.

A single intraperitoneal injection of T-2 toxin (0.35, 1.75, or 3.5 mg/kg body wt) induced time- and dose-dependent thymic atrophy in young female BALB/c mice. T-2 toxin (1.75 mg/kg) induced maximal atrophy by day 3 with complete recovery by day 7. Flow cytometric analysis showed that the CD4(+)CD8(+) double positive thymocyte population decreased markedly. Histopathological examination of the thymus indicated that the pattern of cell death in the thymocytes had a characteristic apoptotic morphology with cell shrinkage and nuclear condensation. The in vivo effects of T-2 toxin included the induction of DNA fragmentation of approximately 200 base pairs in ladder form and cell death in thymocytes. Furthermore, flow cytometric analysis of PI-stained thymocytes from animals dosed with T-2 toxin revealed the formation of apoptotic cells. Of nine kinds of trichothecene mycotoxins tested, T-2 toxin appeared to be the most potent agent to induce apoptosis in the thymus. We sought insight into the mechanism of T-2 toxin-induced apoptosis in vivo. Administration of the protein synthesis inhibitor, CHX (15 mg/kg ip), 5 min after T-2 toxin (1.75 mg/kg ip) inhibited the induction of apoptosis in thymocytes, suggesting that the de novo protein synthesis was necessary. By using adrenalectomized mice and anti-TNF-alpha antibody-injected mice, it was shown that neither endogenous glucocorticoid nor TNF-alpha appeared to be involved in the apoptotic process. Taken together, these findings suggest that T-2 toxin-induced thymic atrophy is associated with cell death through a mechanism of apoptosis.

Copyright 1998 Academic Press.

PMID: 9473527 [PubMed - indexed for MEDLINE]

118. Exp Toxicol Pathol. 1997 Dec;49(6):447-50.

T-2 toxin-induced apoptosis in intestinal crypt epithelial cells of mice.

Li G, Shinozuka J, Uetsuka K, Nakayama H, Doi K.

Department of Veterinary Pathology, Faculty of Agriculture, The University of Tokyo, Japan.

The characteristics of T-2 toxin-induced cell damage in the intestinal crypt epithelia was investigated in mice. Following T-2 toxin-inoculation (0, 2.5, 5 and 10 mg/kg b.w.), dead cells showing pyknosis were sporadically observed in the crypt epithelia, and the nuclei of these cells were strongly stained by the modified TUNEL method which detects fragmented DNA in situ. Electron microscopically, the dead cells were characterized by shrinkage of the cell body and condensation of nuclear chromatin frequently along the nuclear membrane, and such nuclei were sometimes fragmented into small pieces. These morphological characteristics are well consistent with those of apoptosis. The mitotic index in the crypt epithelia drastically decreased at 6 hours after T-2 toxin-inoculation (6 HAI), but thereafter it recovered to almost the same value with that in control mice at 48 HAI. On the other hand, the apoptotic index in the crypt epithelia increased with the lapse of time. Clear mouse strain- and sex-differences were detected in the apoptotic index but not in the mitotic index. This is the first report that T-2 toxin caused apoptotic cell death in the intestinal crypt epithelial cells.

PMID: 9495644 [PubMed - indexed for MEDLINE]

119. Exp Toxicol Pathol. 1997 Dec;49(5):387-92.

T-2 toxin-induced apoptosis in lymphoid organs of mice.

Shinozuka J, Li G, Kiatipattanasakul W, Uetsuka K, Nakayama H, Doi K.

Department of Veterinary Pathology, Faculty of Agriculture, University of Tokyo.

Lymphoid organs of male and female mice of 4 strains (ICR: CD-1, BALB/c, C57BL/6 and DBA/2) were histologically and biochemically examined at 24 hours after oral inoculation of T-2 toxin (0, 2.5, 5 and 10 mg/kg b.w.). Light microscopically, dose-dependent decrease in number of lymphocytes was observed in the thymic cortex and splenic follicles. The nuclei of lymphocytes showed pyknosis or karyorrhexis, and they were positively stained by the modified TUNEL method which detects fragmented DNA in situ. Electron microscopic characteristics of damaged lymphocytes were shrinkage of the cell body, nuclear chromatin condensation and fragmentation. Agarose gel electrophoresis of DNA extracted from the thymus showed DNA fragmentation into nucleosome units, i.e. ladder formation. The above-mentioned findings clearly showed that T-2 toxin could induce apoptotic cell death in the lymphoid organs of mice. These changes were more prominent in female BALB/c and C57BL/6 mice.

PMID: 9455687 [PubMed - indexed for MEDLINE]

120. Vet Rec. 1997 Apr 12;140(15):399-400.

Case study of bovine dermatitis caused by oat straw infected with Fusarium sporotrichioides.

Wu W, Cook ME, Chu FS, Buttles T, Hunger J, Sutherland P.

Department of Poultry Science, University of Wisconsin, Madison 53706, USA.

A dermatitis characterised by discrete, raised, plaque-like and cracked skin lesions of variable sizes on the udder, the hind quarters, the lips and muzzle of all the cows in a herd was suspected of being caused by the oat straw used in bedding, after initial feed analysis and skin culture were negative for toxins and dermatophytes. Mycological analysis indicated an extensive infestation of the oat straw by Fusarium sporotrichioides, a toxic mould, and an immunochemical assay indicated dermatotoxic trichothecenes in the straw (0.22 microgram/g dried straw). An ethyl acetate extract of the straw induced a necrotic response on shaved rat skin. Ingestion of the toxic bedding straw and inhalation of toxic straw dust probably also caused the internal haemorrhage and lung emphysema observed in the two cows that died. The regression of the dermatitis and the recovery of general herd health after the withdrawal of the oat straw further supported the diagnosis.

PMID: 9141223 [PubMed - indexed for MEDLINE]

121. Exp Anim. 1997 Apr;46(2):117-26.

Process of the development of T-2 toxin-induced apoptosis in the lymphoid organs of mice.

Shinozuka J, Guanmin L, Uetsuka K, Nakayama H, Doi K.

Department of Veterinary Pathology, Faculty of Agriculture, University of Tokyo, Japan.

Female ICR:CD-1 mice orally treated with 10 mg/kg b.w. of T-2 toxin were killed at 1, 3, 6, 9, 12, 24 and 48 hr after treatment (HAT) and subjected to examination of the process of the development of T-2 toxin-induced apoptosis in the thymus and spleen. The early ultrastructural changes in lymphocytes characterized by shrinkage of the cell body and condensation of nuclear chromatin were detected at 3HAT in the thymus. The number of apoptotic lymphocytes observed by the in situ detection method for fragmented DNA increased drastically from 9 to 24 HAT in the thymus while it began to increase at 12 HAT in the spleen. The DNA ladder was first detected by agarose gel electrophoresis at 9 HAT and became clearer at 12 and 24 HAT in the thymus but was not clearly detected in the spleen throughout the observation period. Thus T-2 toxin-induced apoptosis developed earlier and was apparently severer in the thymus than in the spleen. Apoptotic was first detected by electron microscopy, then by the in situ detection method for fragmented DNA, and finally by DNA agarose gel electrophoresis.

PMID: 9145291 [PubMed - indexed for MEDLINE]

122. J Vet Med Sci. 1997 Mar;59(3):191-9.

Course of apoptotic changes in the rat gastric mucosa caused by oral administration of fusarenon-X.

Li J, Shimizu T.

Laboratory of Veterinary Pathology, Faculty of Agriculture, Kagoshima University, Japan.

Male 5-week-old Wistar rats orally (po) administered with fusarenon-X (FX) 1.5 mg/kg and control rats po-treated with distilled water were sacrificed at 0-48 hr after gavage. FX-administered rats showed significant dilatation of the stomach with increased fluid contents at 1-24 hr postadministration (PA). Histopathologically, karyopyknosis of chief cells in the basal region of the gastric glands began to appear at 1 hr, and nuclear fragments were seen in the neck cell region at 1.5 hr PA. At 2-4 hr PA, apoptotic cells appeared diffusely in the neck region and focally in the basal region. Electron microscopy revealed that cells phagocytosing apoptotic bodies were the surface epithelia, undifferentiated neck cells, parietal cells and chief cells. No evidence was detected to show that parietal cells underwent apoptotic changes. The apoptotic lesions peaked at 4-6 hr PA, gradually subsided at 12 hr PA, and became minimal leaving apoptotic remnants in the basal region at 24 hr PA. At 48 hr PA, however, diffuse apoptotic lesions reappeared in the basal region at a level similar to that at 2-3 hr PA. This might be attributable to absorption of FX retaining in the stomach for 24 hr. In situ detection of DNA breaks by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) reaction was consistent with the histopathologic findings. Agarose gel electrophoresis of DNA fragments isolated from the gastric mucosae of FX-administered rats showed a ladder pattern after 1.5 hr PA and the pattern became more distinct at 2-4 hr PA.

PMID: 9101478 [PubMed - indexed for MEDLINE]

123. Fundam Appl Toxicol. 1997 Feb;35(2):182-8.

Effects of intranasal exposure to spores of Stachybotrys atra in mice.

Nikulin M, Reijula K, Jarvis BB, Veijalainen P, Hintikka EL.

Veterinary Microbiology and Epidemiology, University of Helsinki, Helsinki, Finland.

The effects of highly toxic and nontoxic spores of Stachybotrys atra were investigated in mice after six intranasal administrations of 1 x 10(5) and 1 x 10(3) spores in phosphate-buffered saline during a 3-week period. Toxic spores contained the trichothecene mycotoxins, satratoxins G and H, as well as the immunosuppressant stachybotrylactones and -lactams. No trichothecenes were detected in the nontoxic spores, and they contained only minor amounts of stachybotrylactones and -lactams. In mice injected with toxic and nontoxic spores, the platelet count was decreased and leucocyte and erythrocyte counts, hemoglobin concentration, and hematocrit were increased. No IgG antibodies to S. atra were detected in sera of mice exposed intranasally to spores. No histological changes were detected in spleen, thymus, or intestines of mice. The mice receiving 1 x 10(5) toxic spores intranasally developed severe inflammatory changes within both bronchioles and alveoli. Hemorrhage was detected in alveoli. The mice receiving 1 x 10(5) nontoxic spores also developed inflammatory changes in the lungs, but these changes were significantly milder than those in mice receiving toxic spores. The mice receiving 1 x 10(3) toxic spores developed inflammatory changes in the lungs that were less severe than those in the mice receiving 1 x 10(5) toxic spores. No inflammatory changes were detected in the mice receiving 1 x 10(3) of nontoxic spores. The present findings indicate that exposure to S. atra spores containing toxins (satratoxins) can be a significant health risk.

PMID: 9038239 [PubMed - indexed for MEDLINE]

124. Nat Toxins. 1997;5(6):238-46.

Influence of dietary nivalenol exposure on gross pathology and selected immunological parameters in young pigs.

Hedman R, Thuvander A, Gadhasson I, Reverter M, Pettersson H.

Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, Uppsala, Sweden.

Young pigs were fed diets to which 0, 2.5, or 5 mg/kg of purified nivalenol (NIV) had been added. The exposure continued for 3 weeks without any signs of feed refusal, vomiting, or change in clinical appearance, and there were no changes in body or organ weights due to the exposure. However, the concluding macroscopic examination revealed gastrointestinal erosions and signs of nephropathy in most of the exposed pigs. There were no differences in total or differential blood leukocyte counts between control and exposed pigs in blood samples collected after 0, 1, or 3 weeks, nor in the number of thymocytes at the end of the trial. Spleen cell numbers showed a dose-dependent decrease after 3 weeks of exposure that was statistically different from controls in pigs exposed to 5 mg NIV/kg. Flow cytometric analysis of lymphocytes revealed decreased numbers of both the CD4+ and the CD8+ subpopulations in the spleen at this point in time, reflecting the lower numbers of splenocytes; but no proportional changes were seen. In blood, exposure to NIV caused a transient decrease in the proportion of CD4+ cells after 1 week of exposure. Analysis of IgG and IgA in plasma showed a time-dependent tendency of increasing plasma concentrations of IgA and decreasing concentrations of IgG in the 2.5 mg/kg group, but differences in Ig levels between experimental groups and controls were not observed at any time. No differences were seen in the mitogen-induced proliferation by lymphocytes from blood, spleen, or thymus. In conclusion, exposure of young pigs to NIV in the diet caused pathological alterations in the kidneys and gastrointestinal tract and reduced the number of splenocytes. The results also indicated that exposure to NIV caused a time-dependent increase in IgA production in the 2.5 mg/kg group.

PMID: 9615312 [PubMed - indexed for MEDLINE]

125. Nat Toxins. 1997;5(4):141-5.

Apoptotic cellular damage in mice after T-2 toxin-induced acute toxicosis.

Ihara T, Sugamata M, Sekijima M, Okumura H, Yoshino N, Ueno Y.

Department of Pathology, Institute of Tochigi Clinical Pathology, Tochigi, Japan.

By histopathologic, electron microscopic, and immunochemical observation, the mechanism of cellular death was investigated in thymus, spleen, and liver of mice given intraperitoneally sublethal doses of T-2 toxin, a trichothecene mycotoxin. In the thymus and spleen of mice given 5.0 mg/kg body weight of T-2 toxin and killed 12 hours later, a massive cellular destruction characterized by chromatin condensation was evident, and electron microscopy analysis revealed the presence of apoptotic bodies. In the liver of mice given 2.5 mg/kg of T-2 toxin and killed 2 hours later, the induction of apoptotic cellular lesions was observed by electron microscopy, and Kupffer cells phagocytosed the apoptotic bodies. Such lesions were not observed in the mice killed 12 hours after receiving the toxin. In situ nick translation analysis (Tunel method) revealed DNA fragmentation in thymus, spleen, and liver shortly after administration of T-2 toxin. As previously observed in vitro, these findings indicated that T-2 toxin is a potent inducer of apoptotic cell death in thymus, spleen, and liver in vivo; especially in liver, apoptosis is induced rapidly as compared with the other tissues observed, and Kupffer cells play an important role for clearance of apoptosis.

PMID: 9407556 [PubMed - indexed for MEDLINE]

126. Nephron. 1997;75(4):469-78.

Experimental IgA nephropathy induced by a low-dose environmental mycotoxin, nivalenol.

Hinoshita F, Suzuki Y, Yokoyama K, Hara S, Yamada A, Ogura Y, Hashimoto H, Tomura S, Marumo F, Ueno Y.

Kidney Center, Toranomon Hospital, Tokyo, Japan.

Based on the hypothesis that IgA nephropathy (IgAN) is triggered by some exogenous antigen(s) which induces dysregulation of the mucosal immune system, we developed an experimental model of orally induced IgAN by an environmental mycotoxin, nivalenol (NIV), which often contaminates agricultural products in Southeast Asia and Japan. In the present study, low doses of oral NIV reproducibly induced significant IgA deposits in the glomerular mesangium and elevated serum IgA levels in mice irrespective of the strain; the degree of immunopathological changes analogous to human IgAN was associated with the dose and duration of NIV treatment. Furthermore, a competitive enzyme-linked immunosorbent assay with an NIV analogue-protein conjugate disclosed that the IgA antibody in the sera from the NIV model mice had a higher affinity to the mycotoxin. Conclusively, these findings suggest that NIV induces some pathological changes in mice which resemble those in human IgAN, and that this mycotoxin is associated with pathogenesis in some types of glomerulonephritis.

PMID: 9127336 [PubMed - indexed for MEDLINE]

127. J Vet Med Sci. 1997 Jan;59(1):17-22.

Rapid apoptotic changes in the gastric glandular epithelium of rats administered intraperitoneally with fusarenon-X.

Li J, Shimizu T, Miyoshi N, Yasuda N.

Laboratory of Veterinary Pathology, Faculty of Agriculture, Kagoshima University, Japan.

Fusarenon-X (FX) 1.5 mg/kg was administered intraperitoneally (i.p.) to 6-week-old male Wistar rats for examination of pathologic effects on the glandular stomach. Rats ip-treated with sterilized physiological saline were used as control. FX-administered rats showed dilatation of the stomach with increased fluid contents after 1-4 hr. Light microscopically, a few apoptotic karyopyknosis were seen in chief cells in the basal region at 1 hr postadministration (PA) and mitotic inhibition was evident after 2 hr PA. Marked apoptosis of nuclear pyknosis and cytoplasmic inclusions in both zymogenic and oxyntic cells developed from basal to middle regions of the gastric mucous membrane at 2-4 hr PA with a peak at 3 hr. Apoptotic changes of differentiating neck cells and surface epithelia were less evident. Electron microscopy revealed that the chief cells were the main target of FX-induced apoptotosis. The parietal cells were secondarily involved because they phagocytosed chief cell-derived apoptotic bodies. In situ detection of DNA breaks by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) reaction revealed the positive nuclei after 1 hr PA, which increased with time and reached a peak at 3 hr PA, in accordance with apoptotic changes in histological study. Agarose gel electrophoresis of DNA isolated from the gastric mucosae of FX-administered rats showed ladder pattern of DNA fragments after 1.5 hr PA with the maximum distinctness at 3 hr PA.

PMID: 9035072 [PubMed - indexed for MEDLINE]

128. Int J Exp Pathol. 1996 Oct;77(5):213-8.

Experimental lung mycotoxicosis in mice induced by Stachybotrys atra.

Nikulin M, Reijula K, Jarvis BB, Hintikka EL.

University of Helsinki, Finland.

Stachybotrys atra is often isolated from building materials in houses with moisture problems. Spores of S. atra can contain mycotoxins which may lead to various symptoms in exposed residents in damp houses. The pathogenesis of S. atra-induced lung diseases has not been elucidated. The purpose of the present study was to investigate lung mycotoxicosis experimentally in mice after an intranasal exposure to spores of S. atra-fungus. One group of mice received one intranasal injection of spores of a toxic strain of S. atra (1 x 10(6) spores) and the other group spores of a less toxic strain. Spores of both strains contained spirolactones and spirolactams while the highly toxic strain contained also trichothecene mycotoxins, satratoxins. The spores containing satratoxins caused severe intra-alveolar, bronchiolar and interstitial inflammation with haemorrhagic exudative processes in the alveolar and bronchiolar lumen. A significant difference was observed in the severity of the lung damage caused by the two strains of S. atra. The spores without satratoxins induced a milder inflammation, so that the toxic compounds of S. atra-spores are most likely responsible for the severity of the lung injury.

PMCID: PMC2691636 PMID: 8977373 [PubMed - indexed for MEDLINE]

129. J Comp Pathol. 1996 Oct;115(3):229-37.

Mycotoxin T-2 and aflatoxin B1 as immunosuppressors in mice chronically infected with Toxoplasma gondii.

Venturini MC, Quiroga MA, Risso MA, Lorenzo CD, Omata Y, Venturini L, Godoy H.

Department of Parasitology, Faculty of Veterinary Science, National University of La Plata, Argentina.

The aim of this study was to determine whether repeated ingestion of mycotoxin T-2 (T2) or aflatoxin B1 (AFL) at low doses could contribute to the activation of toxoplasmosis in experimentally infected mice. Mice were divided into two groups: Control (C) and Infected (I). The cyst-forming Beverley strain of Toxoplasma gondii was used to produce the infection one month before treatment with mycotoxins. Mycotoxins were given intragastrically for a 50-day period. The average weight gain was reduced in the groups treated with mycotoxins. Mice developed specific IgG to T. gondii. Histopathological studies showed severe encephalitis in all groups infected. The number of unruptured and ruptured cysts was established and the severity of the lesions was evaluated, the groups treated with mycotoxins being the most severely affected. Immunohistochemical studies of the brain showed free antigen in tissues surrounding ruptured cysts. It is suggested that low and repeated doses of mycotoxins, necessary to produce a subclinical intoxication, precipitate Toxoplasma cyst rupture and consequently the activation of chronic toxoplasmosis.

PMID: 8923234 [PubMed - indexed for MEDLINE]

130. Nat Toxins. 1996;4(5):234-41.

Transient elevation of intracellular calcium ion levels as an early event in T-2 toxin-induced apoptosis in human promyelotic cell line HL-60.

Yoshino N, Takizawa M, Akiba H, Okumura H, Tashiro F, Honda M, Ueno Y.

Faculty of Pharmaceutical Sciences, Science University of Tokyo, Japan.

Recently we have reported that T-2 toxin, a trichothecene mycotoxin produced by Fusarium species, is a potent inducer of apoptosis in the human promyelotic cell line HL-60. To clarify the signal transduction pathway of apoptosis primed by T-2 toxin, T-2 toxin-induced apoptosis was investigated in detail using confocal laser microscopy and flow cytometry. Apoptosis in HL-60 cells induced by T-2 toxin was dose dependent when the cells were treated with concentrations of 5-100 ng/ml for more than 2 hr. The apoptosis proceeds through various cell cycle stages of HL-60 cells. Prior to apoptosis, the intracellular calcium ion (Ca+2i) level was markedly elevated within 3-5 min after exposure to T-2 toxin and returned to normal level thereafter. A well-known chelator for Ca+2i, ethylene-N,N,N', N'-tetraacetic acid 4K acetoxymethyl ester (BAPTA-AM), a Ca+2-dependent endonuclease inhibitor ZnCl2, and calpain inhibitor 1 sharply blocked T-2 toxin-induced apoptosis. These results strongly suggest that the Ca+2 signal triggered by T-2 toxin is transduced by the activation of endonuclease and protease, and ultimately evokes apoptosis.

PMID: 8946399 [PubMed - indexed for MEDLINE]

131. Proc Soc Exp Biol Med. 1995 Dec;210(3):260-5.

Altered tissue amino acid metabolism in acute T-2 toxicosis.

Meloche JL, Smith TK.

Department of Nutritional Sciences, University of Guelph, Ontario, Canada.

T-2 toxin is a Fusarium trichothecene mycotoxin that has been shown to alter brain neurochemistry and eating behavior in animals eating contaminated diets. Experiments were conducted to determine the role of altered tissue amino acid metabolism in the etiology of acute T-2 toxicosis. Fasted weanling rats were orally dosed with 0 or 2.0 mg T-2 toxin/kg body weight. Blood, brain, liver, and muscle tissue were excised 4 and 8 hr after dosing, and amino acid concentrations were determined. Hepatic enlargement coupled with reduced liver concentrations of free small neutral, large neutral, and basic amino acids were seen 4 hr after dosing. Brain and muscle amino acid concentrations were largely refractory to treatment, while the plasma concentrations of tyrosine and lysine, and the sum of the basic amino acids fell. Hepatic amino acid concentrations returned to control levels 8 hr after dosing at which time aminoacidemia was seen. This was due partially to an increase in plasma concentrations of large neutral amino acids including particularly the branched-chain amino acids. A subsequent experiment was conducted to determine the effect of T-2 toxin on 14C-leucine uptake and incorporation into protein in liver slices 4 hr after dosing. Exposure to T-2 toxin reduced total (free + protein-bound) uptake of leucine due primarily to reduced incorporation of leucine into newly-synthesized hepatic protein. It was concluded that reduced amino acid uptake by liver preceded aminoacidemia in acute T-2 toxicosis, although it is not clear how this might influence subsequent changes in brain neurochemistry and behavior.

PMID: 8539264 [PubMed - indexed for MEDLINE]

132. Z Lebensm Unters Forsch. 1995 Jul;201(1):83-6.

[Comparative investigations of mycotoxological status of alternatively and conventionally grown crops].

[Article in German]

Marx H, Gedek B, Kollarczik B.

Institut für medizinische Mikrobiologie, Infektions- und Seuchenlehre, Ludwig-Maximilians-Universität, München, Germany.

100 samples of rye and 101 samples of wheat coming out of both conventional and alternative or ecological production were investigated for contamination with mycotoxins with interest for our degree of latitude. Deoxynivalenol (DON) was found with thin-layer-chromatography in 131 of 201 samples altogether. A top level of 1250 micrograms DON kg-1 in rye of alternative offspring was detected. The average burden in contaminated rye coming from ecological production was 427 micrograms kg-1 and a mean level of 160 micrograms kg-1 resulting in rye out of conventional growth conditions. In wheat, conventionally grown yield showed slightly lower contamination (mean levels of 420 micrograms DON kg-1 towards 486 micrograms kg-1). The toxins 3-acetyl-deoxynivalenol, nivalenol and fusarenone X were detected in some samples by thin-layer-chromatography. This results could not be confirmed by gas chromatography -mass spectrometry. Zearalenone was found in 40 out of the number of 201 samples of grain by HPLC with fluorescence detection. An average of 6 micrograms and 24 micrograms zearalenone kg-1 in conventionally and alternatively grown wheat and 4 micrograms and 51 micrograms zearalenone kg-1 in conventionally and alternatively produced rye was detected. The highest finding of zearalenone was 199 micrograms kg-1 in alternatively grown rye. Skin toxicity testing did not show any reference of contamination with type-A-trichothecenes. No correlation between contamination of zearalenone or deoxynivalenol and thousand-kernel-weight was detected.

PMID: 7571872 [PubMed - indexed for MEDLINE]

133. Fundam Appl Toxicol. 1995 Jun;26(1):107-16.

Effects of dihydrotestosterone and estradiol on experimental IgA nephropathy induced by vomitoxin.

Greene DM, Azcona-Olivera JI, Murtha JM, Pestka JJ.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing 48824-1224, USA.

Ingestion of the trichothecene vomitoxin (VT) by mice induces effects that mimic the common human glomerulonephritis, IgA nephropathy (IgAN). These include elevation of serum IgA, IgA immune complexes, and mesangial IgA deposition. Based on previous observations that male mice are more prone to VT-induced IgAN, the effects of castration of male and female B6C3F1 mice and sex hormone supplementation on several immunopathologic indicators of the disease were compared. In the first study, castrated and intact male and female mice were fed control AIN-76A diet or the same diet containing 10 ppm VT for 12 weeks. At Week 12, all but the intact female group fed VT exhibited increased serum IgA, with castrated female mice having greater levels than intact females. When microscopic hematuria was used as an indicator of disease severity in intact VT-fed mice, erythrocyte counts for males exceeded those for females at weeks 4 and 12. VT-fed, castrated females exhibited greater hematuria than intact counterparts, whereas VT-fed, castrated males had lower urinary erythrocyte counts than intact counterparts. In a second study, castrated male and female mice were implanted with controlled release pellets of placebo, 5 alpha-dihydrotestosterone (DHT), or 17 beta-estradiol (E2) and then were fed either control diet or a 10 ppm VT diet for 8 weeks. Castrated male and female mice treated with VT and DHT pellet exhibited more severe hematuria, higher IgA levels, and greater mesangial IgA deposition than mice exposed to the same diet with placebo or E2 pellet at Week 8. While VT-fed animals with an E2 pellet exhibited greater hematuria and mesangial IgA deposition at Week 8 than the placebo groups, their IgA levels were not significantly elevated over those for VT-fed mice with a placebo pellet. Relative to two other pathologic markers for IgAN, the aforementioned effects in both studies were generally consistent with mesangial deposition of complement component C3 but not IgG. The results suggest that (1) enhanced male susceptibility to VT-induced IgAN may be related to modulation by the biologically active androgen DHT and (2) while castration of females increased severity of VT-induced IgAN, supplementation of castrated male or female mice with E2 did not reverse this effect but rather increased disease severity.

PMID: 7657054 [PubMed - indexed for MEDLINE]

134. Vet Rec. 1995 May 20;136(20):511-4.

Effect of various levels of T-2 toxin in the immune system of growing pigs.

Rafai P, Tuboly S, Bata A, Tilly P, Ványi A, Papp Z, Jakab L, Túry E.

Department of Animal Hygiene, University of Veterinary Science, Budapest, Hungary.

Four groups of seven-week-old pigs weighing about 9 kg were fed for three weeks a prestarter that contained 0.5, 1.0, 2.0 or 3.0 mg/kg of highly purified T-2 toxin. The average daily intakes of toxin by the pigs were 0.38, 0.81, 1.24 and 1.43 mg, respectively. The experimental and control pigs were immunised with 5 ml aluminum hydroxide gel-absorbed purified horse globulin on the first and fourth days of the treatment period. Blood samples were withdrawn on days 7, 14 and 21 and used for the determination of the titre of anti-horse globulin antibody, for an in vitro lymphocyte proliferation test, using purified horse globulin, phytohaemagglutinin and concanavalin-A and for determinations of the immune complex, the cytotoxic reaction and the phagocytic activity and phagocytic index of circulating granulocytes. The samples taken on day 21 were also used to determine the erythrocyte count, the mean cell volume of the erythrocytes, the haematocrit, the blood haemoglobin concentration, the leucocyte count and the proportion of T lymphocytes. At the end of the experiment samples were taken from the thymus, spleen and mesenteric lymph nodes for histological examination. The diets that contained 2 and 3 mg T-2 toxin/kg caused a significant decrease in the red blood cell count, the mean corpuscular volume and the haemoglobin concentration. A significant decrease in the leucocyte count and the proportion of T lymphocytes was observed in all the treatment groups. There were also dose-dependent, significant decreases in antibody formation and in the blastogenic transformation of lymphocytes, and mild to moderate reactive processes were observed histologically in the lymphoid organs.

PMID: 7660548 [PubMed - indexed for MEDLINE]

135. Vet Rec. 1995 May 13;136(19):485-9.

Effect of various levels of T-2 toxin on the clinical status, performance and metabolism of growing pigs.

Rafai P, Bata A, Ványi A, Papp Z, Brydl E, Jakab L, Tuboly S, Túry E.

Department of Animal Hygiene, University of Veterinary Science, Budapest, Hungary.

In two sets of experiments eight groups of seven-week-old pigs weighing about 9 kg were fed for three weeks a prestarter that contained 0.5, 1.0, 2.0, 3.0, 4.0, 5.0, 10.0 or 15.0 mg/kg of highly purified T-2 toxin. The feed of the two control groups was free from T-2 toxin. Average daily intakes of toxin by the pigs were 0.38, 0.81, 1.24, 1.43, 0.93, 0.81, 0.99 and 2.5 mg, respectively. The weight gains, the feed intakes, the extent of feed refusal, the parameters of energy and protein metabolism and the serum concentrations of calcium, inorganic phosphorus and magnesium were affected to different extents by the different doses of T-2 toxin, but the data indicated that feed consumption was reduced and the activity of aspartate aminotransferase was increased by the smallest amount of T-2 toxin tested.

PMID: 7645184 [PubMed - indexed for MEDLINE]

136. Food Chem Toxicol. 1995 Mar;33(3):217-22.

Lack of initiation and promotion potential of deoxynivalenol for skin tumorigenesis in Sencar mice.

Lambert LA, Hines FA, Eppley RM.

Division of Science and Applied Technology, US Food and Drug Administration, Washington, DC 20204.

The mycotoxin deoxynivalenol (DON; vomitoxin) was tested for its potential to initiate or promote skin tumours through a two-stage treatment regimen in female Sencar mice. DON's capability for initiation was tested by applying a single topical dose (200 micrograms) followed by multiple treatments of the promoter phorbol 12-myristate 13-acetate (PMA). The test for promotion involved initiation with the carcinogen 7,12-dimethylbenz[a]anthracene (DMBA) followed by multiple DON treatments (50 micrograms). Appropriate control groups were included in the study design. Mice were observed for 26 wk and skin tumours were counted. Results of the study showed that DON was not an initiator or a promoter. When DON was tested as an initiator, there were no statistically significant differences in the number of cumulative tumours or the number of tumour-bearing mice between the DON-initiated/PMA-promoted group and its control, the vehicle-initiated/PMA-promoted group. When DON was administered as a promoter, no tumours were observed. Histopathology of the skin revealed that DON induced a mild diffuse squamous hyperplasia, but there was no progression of the lesion to neoplasia.

PMID: 7896232 [PubMed - indexed for MEDLINE]

137. Teratog Carcinog Mutagen. 1995-1996;15(6):283-306.

Chronic feeding study of deoxynivalenol in B6C3F1 male and female mice.

Iverson F, Armstrong C, Nera E, Truelove J, Fernie S, Scott P, Stapley R, Hayward S, Gunner S.

Toxicology Research Division, Health Protection Branch, Ottawa, Ontario, Canada.

A 2 year feeding study was conducted with male and female B6C3F1 mice that consumed diets containing 0, 1, 5, or 10 ppm deoxynivalenol (DON). Survivability was good and, while the test animals gained less weight with increasing levels of DON in the diet, there were no consistent toxic manifestations associated with DON consumption. There was some evidence for an increase in serum IgA and IgG in females, and there were sporadic changes noted in the clinical chemistry and hematology parameters conducted at the terminal sacrifice. However, these changes were not considered to be biologically significant. The pathology results provided statistically significant dose-related evidence for a decrease in liver preneoplastic and neoplastic lesions as the dose level of DON increased. This negative trend probably results from the known positive correlation between body weight and the appearance of spontaneous hepatic neoplasms in this strain of mouse.

PMID: 8732880 [PubMed - indexed for MEDLINE]

138. Nat Toxins. 1995;3(3):129-37.

Induction of apoptosis by T-2 toxin and other natural toxins in HL-60 human promyelotic leukemia cells.

Ueno Y, Umemori K, Niimi E, Tanuma S, Nagata S, Sugamata M, Ihara T, Sekijima M, Kawai K, Ueno I, et al.

Faculty of Pharmaceutical Sciences, Science University of Tokyo, Japan.

Based on the DNA fragmentation profile in gel electrophoresis and the morphological changes in electron microscopy, the induction of apoptotic nuclear changes by mycotoxins and other microbial products, in total 31 chemicals, was investigated in HL-60 human promyelotic leukemia cells, along with the cytotoxicity tests with 3-[4,5-dimethylthiazol-zyl]-2,5-diphenyltetrazolium bromide (MTT) and trypan blue exclusion. Among the chemicals tested, trichothecenes (T-2 toxin, roridin A, nivalenol, deoxynivalenol), certain anthraquinones (luteoskyrin, skyrin, 2-hydroxyemodin), diketopiperazines (emethallicin A, emestrin), isocoumarins (ochratoxin A, citrinin), lactone (penicillic acid), dihydrobisfuran (aflatoxin B1), potassium ionophore (valinomycin), and an inhibitor of interleukin-2 synthesis (cyclosporin A) were positive for the induction of DNA fragmentation. No DNA fragmentation was observed under the present conditions with fumonisin B1, cyclic peptides (cyclochlorotine, phalloidin, microcystin-LR), certain anthraquinones (emodin, chrysophanol, rugulosin), and others (sterigmatocystin, cytochalasin A, griseofulvin, fusaric acid, kojic acid, rubratoxin B, butenolide, wortmannin, FK506, and sphingosine). The apoptotic changes in the cells exposed to T-2 toxin and luteoskyrin were confirmed by electron microscopic observation. Detailed experiments on dose and time dependencies revealed that T-2 toxin induced the apoptosis at 10 ng/ml (= 4 x 10(-8) M) levels within 2-6 hr without significant cytotoxicity evaluated by the dye exclusion and MTT.

PMID: 7648021 [PubMed - indexed for MEDLINE]

139. Toxicology. 1994 Sep 6;92(1-3):245-60.

Vomitoxin (deoxynivalenol)-induced IgA nephropathy in the B6C3F1 mouse: dose response and male predilection.

Greene DM, Azcona-Olivera JI, Pestka JJ.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing 48824-1224.

Oral exposure to the trichothecene vomitoxin (VT or deoxynivalenol) in mice induces marked elevation of total and autoreactive IgA, IgA immune complexes, and mesangial IgA deposition in a manner that is highly analogous to human IgA nephropathy. In this study, immunopathologic markers indicative of IgA nephropathy were compared in male and female B6C3F1 mice fed semipurified AIN-76A diet containing 0, 2, 10 or 25 ppm VT for 12 weeks. Males fed 10 and 25 ppm VT and females fed 25 ppm VT had increased serum IgA at 4 weeks. At week 8, male mice fed the minimal dose of 2 ppm VT and female mice fed 10 ppm also exhibited elevated serum IgA. IgA levels were consistently higher in treatment males than females with significant differences being observed in the 10-ppm dose group at 4 and 12 weeks. IgA coproantibodies were marginally increased (maximum of 2-fold) in mice of both genders fed 10 and 25 VT. At 8 and 12 weeks, serum IgM was depressed in male and female mice eating 10 and 25 ppm VT, whereas consistent effects on serum IgG or IgE were not observed. In similar fashion, male mice in the 2, 10 and 25 ppm VT groups exhibited microscopic hematuria as early as 4 weeks, whereas this occurred in females fed 10 and 25 ppm VT only at week 10 with urinary erythrocyte counts being lower than male counterparts. Mesangial deposition of IgA and C3 was significantly increased in males exposed to 2, 10 and 25 ppm VT and in females exposed to 10 and 25 ppm VT, with males exhibiting a greater deposition than corresponding females. Based on these immunological parameters, males appeared more susceptible than female mice to VT-induced IgA dysregulation and IgA nephropathy in terms of latency, threshold dose, and severity.

PMID: 7940564 [PubMed - indexed for MEDLINE]

140. Toxicon. 1994 Sep;32(9):1115-23.

Hematopoietic alterations after exposure to T-2 mycotoxin.

Smith BJ, Holladay SD, Blaylock BL.

Department of Biomedical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg 24061-0442.

Adult mice were exposed by oral gavage to 0.75, 1.25, or 1.75 mg/kg body weight T-2 mycotoxin for 5 consecutive days. Thymic atrophy on the 2nd day following cessation of dosing was profound, and was characterized by significant decreases in the total number of cells within all phenotypes defined by CD4 and CD8 cell-surface antigen expression. Further, the distribution of thymocytes within these phenotypes was significantly altered. Increased percentages of CD4-8- (DN) and decreased percentages of CD4+8+ (DP) cells in thymuses from treated animals suggested that T-2 toxin may inhibit thymocyte maturation. In addition to thymus, the bone marrow of treated animals showed a highly significant hypocellularity, indicating that this hematopoietic compartment may also be targeted by T-2 toxin. A trend toward reduced splenic cellularity was additionally observed in exposed animals, but failed to reach significance. A significant decrease in the total number of both B and T-lymphocytes present within the spleen was observed, however. These data, taken together, indicate that effects at multiple hematopoietic compartments involved in the production of T-lymphocytes may contribute to the peripheral T-cell lymphocytopenia and T-cell mediated immunosuppression produced by T-2 toxin.

PMID: 7801347 [PubMed - indexed for MEDLINE]

141. Nat Toxins. 1994;2(6):371-7.

Injury and recovery process of intestine caused by okadaic acid and related compounds.

Ito E, Terao K.

Research Center for Pathogenic Fungi and Microbial Toxicoses, Chiba University, Japan.

The injuries and repair processes in the intestines of mice induced by dinophysistoxin 3 (DTX 3) were compared morphologically to those induced by okadaic acid (OA) and dinophysistoxin 1 (DTX 1). DTX 3 impaired intestinal villi by the oral route only, whereas OA and DTX 1 caused intestinal injury with both oral and intraperitoneal exposures. The character of the lesions caused by the 3 toxins and the recovery processes were highly similar. Within 5 min of dosing, the basal portion of the covering epithelium became homogeneous and peeled from the lamina propria, while the upper portion containing microvilli remained intact. There were two types of villous injury and recovery: 1) When the injuries were limited to the villi, new cells from the crypts moved upward and differentiated into columnar cells. 2) When injuries progressed into the glands of Lieberkuhn, clusters of crypt cells were exposed to the intestinal lumen, and in the most severe case they were completely separated. Villous fusion was often seen in the recovery process of the type 2 cases. Recovery from the injuries was almost completed within 2 days. When mice were pretreated with fusarenon-X, a mycotoxin which injuries undifferentiated crypt cells preferentially, the injury induced by OA to the intestinal crypts was exacerbated and the recovery was delayed.

PMID: 7704451 [PubMed - indexed for MEDLINE]

142. J Toxicol Sci. 1993 Aug;18(3):155-66.

Recombinant human granulocyte colony-stimulating factor accelerates regeneration after T-2 toxin-induced hemopoietic injury and lessens lethality in mice.

Ohtani K, Nanya T, Aoyama Y, Matsunami S, Sekijima M, Kawamura O, Ohtsubo K, Ueno Y.

Department of Toxicology and Microbial Chemistry, Faculty of Pharmaceutical Sciences, Science University of Tokyo.

The effects of rhG-CSF on T-2-induced leukopenia and lethal toxicity in mice were investigated. First, T-2 was administered by gavage to adult male mice at a dose of 3 mg/kg b.w. daily for 7 days, and rhG-CSF was given i.p. in daily dose of 10 or 30 micrograms/kg b.w./day, beginning on the 2nd day, for 5 days. The peripheral WBC of mice receiving T-2 alone was decreased to one fourth of control counts, and bone marrow (BM) cell counts were also markedly diminished. The administration of rhG-CSF prevented those T-2-induced depressions. Histologically, the delation of the hematopoietic cells from BM and spleen of mice given T-2 was remarkably counteracted by administration of rhG-CSF. In the other experiment, rhG-CSF was injected i.p. for 5 days beginning on the next day of the 7-day T-2 administration. The recovery of WBC and BM cell counts was hastened by rhG-CSF reaching the control level in 6 days, and differential leukocyte analysis revealed an increase of neutrophils. Furthermore, simultaneous administration of rhG-CSF depressed the T-2-induced lethal toxicity, dose-dependently. The results revealed that rhG-CSF possesses a potent ability to protect T-2-induced leukopenia and lethality in mice, and it could be as an antidote against T-2 and related trichothecene-induced acute intoxication.

PMID: 7504113 [PubMed - indexed for MEDLINE]

143. Vet Res Commun. 1993;17(4):283-94.

The effects of naturally deoxynivalenol-contaminated oats on the clinical condition, blood parameters, performance and carcass composition of growing pigs.

Bergsjø B, Langseth W, Nafstad I, Jansen JH, Larsen HJ.

Department of Toxicology and Chemistry, National Veterinary Institute, Oslo, Norway.

A feeding trial with naturally deoxynivalenol (DON)-contaminated oats included in feed mixtures at graded levels was conducted in growing pigs. The DON concentrations were 0, 0.7, 1.7, and 3.5 mg/kg of complete feed mixture given ad libitum to different groups. The data recorded were feed consumption, body weight gain, slaughter weight, biochemical and haematological data including serum immunoglobulin A, clinical condition and post-mortem pathology including histopathology. Significantly decreasing body weight gain throughout the experimental period, decreased slaughter weight and reduced feed utilization efficiency were observed for the group fed a diet containing 3.5 mg/kg of DON. At the same DON concentration, there were increased liver weights and decreased concentrations of serum protein and albumin, and a temporary fall in packed blood cell volume, serum calcium and serum phosphorus. For the groups fed diets containing 1.7 and 3.5 mg/kg of DON, a statistically significant, dose-related decrease in daily feed consumption was observed. No other effects on haematological, biochemical or immunological parameters were recorded. The carcass quality was not affected in any group. It was concluded that significant effects in growing pigs may be observed at a dietary DON concentration of 1.7 mg/kg, originating from naturally contaminated oats included in a diet that was otherwise adequate and contained only minor traces of other mycotoxins.

PMID: 8146954 [PubMed - indexed for MEDLINE]

144. Appl Environ Microbiol. 1992 Oct;58(10):3233-9.

Toxin production by Fusarium species from sugar beets and natural occurrence of zearalenone in beets and beet fibers.

Bosch U, Mirocha CJ.

Department of Plant Pathology, University of Minnesota, St. Paul 55108.

Fifty-five Fusarium isolates belonging to nine species were collected from fungus-invaded tissue of stored sugar beets and identified as F. acuminatum (11 isolates), F. avenaceum (1 isolate), F. culmorum (1 isolate), F. equiseti (23 isolates), F. graminearum (4 isolates), F. oxysporum (1 isolate), F. solani (4 isolates), F. sporotrichioides (7 isolates), and F. subglutinans (2 isolates). All isolates were cultured on autoclaved rice grains and assayed for toxicity by feeding weanling female rats the ground-rice cultures of the isolates in a 50% mixture with a regular diet for 5 days. Fifty-eight percent of the isolates were acutely toxic to rats, 26% caused hematuria, 18% caused hemorrhages, and 29% caused uterine enlargement. In most cases, toxicity could not be accounted for by the known toxins found. The following mycotoxins were found in extracts of the rice cultures: zearalenone (22 to 6,282 micrograms/g), chlamydosporol (HM-8) (68 to 4,708 micrograms/g), moniliformin (45 to 400 micrograms/g), deoxynivalenol (10 to 34 micrograms/g), 15-acetyldeoxynivalenol (5 to 10 micrograms/g), diacetoxyscirpenol (22 to 63 micrograms/g), monoacetoxyscirpenol (21 to 26 micrograms/g), scirpenetriol (24 micrograms/g), T-2 toxin (4 to 425 micrograms/g), HT-2 toxin (2 to 284 micrograms/g), neosolaniol (2 to 250 micrograms/g), and T-2 tetraol (4 to 12 micrograms/g). F. equiseti was the predominant species found on visibly molded beets in the field. Six of 25 moldy sugar beet root samples collected in the field contained zearalenone in concentrations ranging between 12 and 391 ng/g, whereas 10 samples from commercial stockpiles were negative for zearalenone.(ABSTRACT TRUNCATED AT 250 WORDS)

PMCID: PMC183085 PMID: 1444361 [PubMed - indexed for MEDLINE]

145. Toxicol Lett. 1991 Jun;57(1):1-9.

Central effects of cycloheximide alone and of its combination with T-2 toxin.

Bergmann F, Feinmesser M, Yagen B.

Department of Pharmacology, School of Pharmacy, Hebrew University-Hadassah Medical School, Jerusalem, Israel.

The antibiotic cycloheximide inhibits protein synthesis in eukaryotic cells. This overall effect is similar to that of T-2 toxin, but the mechanism of intoxication by these two inhibitors are different. This is shown here by intracerebral injections of mixtures of T-2 toxin and cycloheximide, leading to potentiation of their toxic effects. The histopathology of cerebral intoxication by the two compounds is similar, but after cycloheximide the lesions appear earlier, and repair is faster.

PMID: 2048154 [PubMed - indexed for MEDLINE]

146. Acta Vet Hung. 1991;39(1-2):29-37.

Changes induced in newborn piglets by the trichothecene toxin T-2.

Ványi A, Glávits R, Gajdács E, Sándor G, Kovács F.

University of Veterinary Science, Budapest, Hungary.

Three pregnant sows, being in the last quarter of gestation, were used in an experiment to study the changes induced in newborn piglets by T-2 toxin. One sow was used as control (C). The other two received 24 mg (sow A) and 6 mg (sow B) T-2 toxin, respectively, mixed in the feed, daily, up to the time of farrowing. The piglets of sow A became ill by 48-72 h after birth, while the litters of sow B and C remained healthy. The clinical symptoms included faintness, diarrhoea, decreased blood glucose level, and collapse followed by death. The milk and urine of sow A and the stomach contents of affected and dead piglets contained T-2 toxin and its metabolites. Pathological changes seen at necropsy included acute enteritis, degeneration of the liver and kidneys, and oedema of the mesentery. The stomach was filled with clotted milk. Histopathological and electron-microscopic findings consisted of reduced glycogen content and pathological simple fatty infiltration of the liver cells, lymphocyte depletion and necrosis in the lymphoid follicles of the intestinal mucosa, atrophy of the thymic cortex, and hyperfunction of the adrenal and thyroid glands compared to the control.

PMID: 1750363 [PubMed - indexed for MEDLINE]

147. J Comp Pathol. 1990 Nov;103(4):379-85.

Differentiation of lesions caused by mycotoxin T-2 from autolytic morphologic change in CD-1 mice.

Rousseaux CG, Schiefer HB, Hancock DS, Olfert ED.

Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada.

Experiments with topically applied T-2 trichothecene mycotoxin were undertaken to determine whether lesions caused by this toxin could be differentiated from autolysis. Two pathologists, who had previously seen lesions caused by T-2 toxin, graded lesions without knowledge of treatment group and stated whether the animal had received the toxin or not. Both pathologists differentiated T-2 toxin-treated mice up to 6 h post-mortem. Failure to distinguish between treated and control mice resulted in false-negative diagnoses only. It was concluded that the diagnosis of trichothecene mycotoxicosis would probably be missed more than 6 h post-mortem.

PMID: 2079553 [PubMed - indexed for MEDLINE]

148. Food Chem Toxicol. 1990 Oct;28(10):687-92.

Modulation of resistance to mastitis pathogens by pretreatment of mice with T-2 toxin.

Cooray R, Jonsson P.

Department of Zoophysiology, University of Uppsala, Sweden.

T-2 toxin, a secondary metabolite of Fusarium species, is a mycotoxin with immunomodulatory activity. In the present investigation the effects of T-2 toxin on host resistance was studied. The virulence of Escherichia coli and Staphylococcus aureus in the mammary glands of mice treated with T-2 toxin was compared with their virulence in control mice. Virulence was estimated from the ability to induce various types of lesions and bacterial growth in the mammary gland. Pretreatment of mice with a single dose (3 mg/kg body weight) of T-2 toxin by gavage reduced the virulence of both E. coli (P less than 0.05) and S. aureus (P less than 0.01). Microscopic lesions in the infected glands varied in character, from consistently non-reactive necrosis of the entire mammary gland to limited inflammatory reactions. The former were more abundant in control mice than in mice treated with T-2 toxin. Although treatment by gavage with T-2 toxin (0.75 mg/kg body weight/day) for 14 days prior to inoculation had no significant effect on the course of the mastitis infection, virulence was slightly lower in the T-2 toxin treated mice. Both single-dose and successive treatment with T-2 toxin enhanced the respiratory burst activity of macrophages. Pre-inoculation treatment with T-2 toxin also caused a significant increase in the number of peritoneal cells, T-2 toxin did not show bacterial effects on the E. coli or S. aureus strains used for the inoculations. The data indicate that T-2 toxin has modulatory effects on the cell-mediated immune system, and that enhancement of resistance to common mastitis pathogens in mice pretreated with a single dose of T-2 toxin is associated with migration and activation of macrophages.

PMID: 2276697 [PubMed - indexed for MEDLINE]

149. Anticancer Res. 1990 Jul-Aug;10(4):1013-7.

Selective effect of trichotecolone on hemopoietic tumor cells.

Goetsch L, Thomasset N, Vila J, Philip I, Doré JF.

INSERM U.218, Centre Leon Berard, Lyon, France.

The effects of trichothecolone, a mycotoxin produced by the mould Trichothecium roseum, were tested at graded concentrations (50 to 250 micrograms/ml) on the in vitro growth of human and murine normal (CFU-GM, IARC 171, FDC-P2) and tumoral (HL60, P388, L1210) hemopoietic cells. A selective cytotoxicity towards tumor cells was observed: an irreversible, concentration dependent inhibition of growth being seen on all tumor cell lines under consideration, while normal cells appeared to be rather insensitive to this drug. In vivo, trichothecolone significantly increased the survival of mice bearing P388 leukemia: a 150 mg/kg/dose, 5 times a day, for 5 days led to a T/C of 145%. Both in vitro and in vivo data suggest that trichothecolone may be an interesting antitumor agent, particularly considering the clear difference in sensitivity of normal and tumor cells to this drug.

PMID: 2382972 [PubMed - indexed for MEDLINE]

150. J Vet Diagn Invest. 1990 Jul;2(3):227-9.

Cutaneous ulceration and necrosis in pigs fed aflatoxin- and T-2 toxin-contaminated diets.

Harvey RB, Kubena LF, Corrier DE, Huff WE, Rottinghaus GE.

USDA, Agricultural Research Service, Veterinary Toxicology and Entomology Research Laboratory, College Station 77840.

PMID: 2094450 [PubMed - indexed for MEDLINE]

151. J Environ Pathol Toxicol Oncol. 1990 May-Jun;10(3):103-5.

A method for accurate measurement of cutaneous irritancy of trichothecenes.

Hayes MA, Schiefer HB.

Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada.

Conventional skin irritation bioassays for trichothecenes are semiquantitative because test animals vary in sensitivity, and the intensity of cutaneous inflammation is poorly correlated with dose. A quantitative bioassay was therefore devised for toxicological studies on the irritancy of trichothecenes. A graded series of six standard solutions of T-2 toxin (10-60 micrograms/mL) in 2 microL volumes was applied to the shaved skin of young female Wistar rats. Each test sample was applied at least twice to each of five rats. After 48 hours, reactions were rated in units of equivalent concentrations of T-2 toxin, so that measurements were independent of the intensity of inflammatory reaction. Mean concentrations of replicate measurements of test solutions of T-2 toxin between 10 and 60 micrograms/mL were precise (SEM less than 1.6 micrograms/mL) and accurate (within 13% of actual concentrations).

PMID: 2254857 [PubMed - indexed for MEDLINE]

152. Mycopathologia. 1990 Mar;109(3):149-55.

T-2 toxin impairment of murine response to Salmonella typhimurium: a histopathologic assessment.

Tai JH, Pestka JJ.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing 48824-1224.

T-2 toxin and other trichothecene mycotoxins experimentally impair normal immune function and may predispose humans and animals to infectious disease. In this study, the histopathologic effects of Salmonella typhimurium challenge concurrently with sublethal T-2 toxin exposure were examined in the Salmonella-resistant C3H/HeN mouse. Oral administration of T-2 toxin (1 mg/kg) every other day for 10 d had little effect on the tissues examined when compared to control animals. Mice challenged with S. typhimurium and then treated with T-2 toxin every other day for 10 d had markedly larger and more bacterial-related lesions in the spleens, kidneys, and livers than animals challenged with S. typhimurium alone. Differences in bone marrow, Peyer's patches and ileal tissues were less discernable between S. typhimurium and S. typhimurium plus T-2 toxin treated groups. These results were consistent with previous findings that T-2 toxin compromised murine resistance to S. typhimurium infection and ultimately caused death in animals challenged with a sublethal dose of the organism.

PMID: 2191223 [PubMed - indexed for MEDLINE]

153. Appl Environ Microbiol. 1990 Feb;56(2):520-5.

Absence of trichothecenes in toxigenic isolates of Fusarium moniliforme.

Mirocha CJ, Abbas HK, Vesonder RF.

Department of Plant Pathology, University of Minnesota, St. Paul 55108.

Thirty-four isolates of Fusarium moniliforme were obtained from cereal grains collected in various parts of the world. The isolates were grown on rice and tested as a diet for toxicity to rats. Of these isolates, 53% caused death, 12% caused congestion and hemorrhage of the stomach and intestine as well as hematuria, 21% caused diarrhea, 38% caused weight loss, and 9% were nontoxic. The cultures were tested to T-2, HT-2, neosolaniol, acetyl-T-2, T-2-tetraol, iso-T-2, diacetoxyscirpenol, monoacetoxyscirpenol, deoxynivalenol, nivalenol, fusarenone-X, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, zearalenone, moniliformin, fusarochromanone, fusarin-C, and wortmannin; all were negative. In addition, F. moniliforme NRRL A25820 was grown on corn and banana fruit as solid substrates as well as on a defined liquid medium; none of the above toxins were found. When F. moniliforme NRRL A25820 was incorporated into a rat diet, no toxicity was noted. Twenty-eight additional isolates of F. moniliforme, isolated from feed associated with equine leukoencephalomalacia, were grown on cracked corn for 2 weeks. The cultures were negative when tested for deoxynivalenol, 15-acetyldeoxynivalenol, diacetoxyscirpenol, monoacetoxyscirpenol, nivalenol, and fusarenone X. Seventy-five percent of the isolates were toxic to ducklings, indicating the presence of a toxin other than trichothecenes. Our results support the conclusion that F. moniliforme does not produce trichothecenes.

PMCID: PMC183371 PMID: 2306091 [PubMed - indexed for MEDLINE]

154. Arch Toxicol. 1990;64(3):251-3.

Prevention of T-2 toxin-induced morphologic effects in the rat by highly activated charcoal.

Bratich PM, Buck WB, Haschek WM.

Department of Veterinary Biosciences, University of Illinois, College of Veterinary Medicine, Urbana.

The efficacy of a highly activated charcoal in preventing the morphologic effects of T-2 toxin was examined in female rats. T-2 toxin at 25 mg/kg (6 x LD50) was given orally to all rats. Half the rats also received the charcoal, at a dose of 9 ml/kg and a concentration of 104 mg/ml, while the other half received water. A charcoal-treated rat (T-2 toxin + charcoal) was killed at the time of death of each positive control animal (T-2 toxin alone). Severe necrosis was seen in the spleen, thymus, stomach, small intestine, liver and adrenal glands of the positive controls (T-2 toxin alone). Lesions were absent or minimal in the paired charcoal-treated rats (T-2 toxin + charcoal).

PMID: 2372237 [PubMed - indexed for MEDLINE]

155. Fundam Appl Toxicol. 1990 Jan;14(1):54-9.

Acute inhalation toxicity of T-2 mycotoxin in the rat and guinea pig.

Creasia DA, Thurman JD, Wannemacher RW Jr, Bunner DL.

Pathophysiology Division, U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland 21701-5011.

In this study, concentration-response parameters were determined for rats and guinea pigs systematically exposed to an aerosol of T-2 toxin. The LC50 for a 10-min exposure to T-2 toxin aerosol was 0.02 mg T-2/liter air for rats and 0.21 mg T-2/liter air for guinea pigs. Data from total T-2 deposition in rats and guinea pigs exposed to their respective LC50 aerosol concentration gave an LD50 of 0.05 mg T-2/kg body weight for the rat and 0.4 mg T-2/kg body weight for the guinea pig. These data show that inhaled T-2 toxin is approximately 20 times more toxic to the rat (0.05 mg T-2/kg body wt inhaled vs 1.0 mg T-2/kg body wt ip) and at least twice as toxic to the guinea pig (0.4 mg T-2/kg body wt inhaled vs 1-2 mg T-2/kg body wt ip) than ip administered T-2 toxin. Histopathologic examination of major organs in both the rat and guinea pig after respiratory exposure to T-2 toxin indicated that lesions were similar to those described after systemic administration of the toxin. Gross and microscopic alterations of respiratory tract tissue after T-2 aerosol exposure were minimal and could not account for the increase in toxicity.

PMID: 2307322 [PubMed - indexed for MEDLINE]

156. J Environ Pathol Toxicol Oncol. 1990 Jan-Apr;10(1-2):69-73.

Synergistic effects of T-2 toxin and a low protein diet on erythropoiesis in mice.

Hayes MA, Schiefer HB.

Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada.

Young male Swiss mice fed on a semipurified diet containing 8% protein and 10 ppm of T-2 toxin developed erythroid hypoplasia within 2 weeks. Red blood cell counts declined to 36% of control values by 6 weeks but had risen to 45% of control values by 8 weeks. Between 4 and 8 weeks, erythropoietic tissues regenerated and reticulocyte counts became greatly elevated. The toxin-free semipurified diet was adequate for normal growth and did not cause anemia in control mice fed either ad lib, or at a restricted rate. Anemia did not occur in mice fed the 10-ppm level to T-2 toxin in either a semipurified diet containing 16% protein, or in a balanced natural-ingredient mouse diet. These observations demonstrated that the inhibitory effect of T-2 toxin in erythropoiesis in mice was transient, and depended on the nutritional composition of the diet.

PMID: 2231317 [PubMed - indexed for MEDLINE]

157. J Environ Pathol Toxicol Oncol. 1990 Jan-Apr;10(1-2):52-5.

Experimental fusariotoxicosis of swine produced by zearalenone and T-2 toxins.

Palyusik M, Harrach B, Horvath G, Mirocha CJ.

Veterinary Medical Research Institute, Hungarian Academy of Sciences, Budapest.

PMID: 2146383 [PubMed - indexed for MEDLINE]

158. Reprod Toxicol. 1990;4(3):215-22.

Anguidine-induced testicular injury in Lewis rats.

Conner MW, Conner BH, Rogers AE, Newberne PM.

Department of Pathology, Boston University School of Medicine, Massachusetts.

Anguidine (diacetoxyscirpenol, DAS) and other trichothecene mycotoxins are potent inhibitors of protein synthesis and injure organs with rapidly dividing cell populations, including the testis. Testicular structure and function were studied in male Lewis rats 1, 3, 7, 30, 60, and 90 days after exposure at age 12 weeks to anguidine at 1.7 mg/kg body weight given by ip injection. The dose was equivalent to 75% of the ip LD50. Anguidine caused a gradual decline in testicular weight beginning 30 days after treatment. Sperm production was also reduced by 30 days, and the frequency of hypocellular seminiferous tubules increased by day 60. There was no evidence of recovery by 90 days. These changes are consistent with injury to proliferating cells early in the maturation sequence. Epididymal sperm reserves were reduced by 3 days after anguidine administration, prior to the reduction in sperm production, suggesting premature release of spermatozoa from the epididymis.

PMID: 2136039 [PubMed - indexed for MEDLINE]

159. Mycopathologia. 1989 Nov;108(2):73-9.

Toxicity and toxin production by Fusarium isolates from New Zealand.

Bosch U, Mirocha CJ, Abbas HK, di Menna M.

Department of Plant Pathology, University of Minnesota, St. Paul 55108.

Sixty-two isolates of Fusarium were obtained from pasture grass and soil from various areas of New Zealand and identified as F. anthophilum, F. avenaceum, F. crookwellense, F. culmorum, F. graminearum, F. nivale, F. oxysporum, F. sambucinum, F. semitectum, F. tricinctum and an unidentified Fusarium spp. These isolates were grown on autoclaved rice and tested for toxicity to rats in feeding tests. Eighty two percent of the isolates were toxic, of which twenty-four percent were severely toxic and caused hemorrhages of stomach and intestine, hematuria, and finally death. Cultures of the most toxic isolates contained 0.1 to 104 ppm of deoxynivalenol, 0.7 and 7 ppm of 15- and 3-acetyldeoxynivalenol respectively, 0.2 to 4 ppm of fusarenon-X, 11 to 1021 ppm zearalenone, 40 to 272 ppm of the hemorrhagic factor (wortmannin), 2,100 to 7,200 ppm of moniliformin, 565 ppm of the cytotoxic factor (HM-8) and enniatin in substantial concentrations. F. sambucinum is reported as a moniliformin producer for the first time.

PMID: 2594049 [PubMed - indexed for MEDLINE]

160. Lab Anim Sci. 1989 Nov;39(6):603-6.

Effect of T-2 toxin on feed intake, digestion and pathology of rabbits.

Fekete S, Tamas J, Vanyi A, Glavits R, Bata A.

Department of Animal Nutrition, University of Veterinary Sciences, Budapest, Hungary.

Feed containing sublethal T-2 toxin concentrations (12.5 and 25 ppm) was fed to adult rabbits. The animals ate 60-70% less toxin-containing food. The dry matter content of their feces decreased significantly (on an average by 10%). The nutrient digestibility of the feed containing 12.5 ppm T-2 toxin, was increased by 2-6% and that of the 25 ppm T-2 toxin level decreased by 4-11% as compared to the control values. The rabbits showed emaciation, subacute catarrhal gastritis, necrosis of the lymphoid cells of the intestinal mucosa, depletion and necrosis in the lymphoid follicles of the ampulla ilei, spleen and lymph nodes. Necrosis of the cells of mononuclear phagocyte system and myeloid hemacytogenesis was characteristic. The toxin concentration of feces, cecotroph and urine was proportional to intake.

PMID: 2593640 [PubMed - indexed for MEDLINE]

161. Fundam Appl Toxicol. 1989 Oct;13(3):523-32.

Evaluation of a superactivated charcoal paste and detergent and water in prevention of T-2 toxin-induced local cutaneous effects in topically exposed swine.

Biehl ML, Lambert RJ, Haschek WM, Buck WB, Schaeffer DJ.

Illinois Animal Poison Information Center, Department of Veterinary Biosciences, Urbana.

T-2 toxin (6 mg) dissolved in 90% DMSO was topically applied to nine 9-cm2 sites on the dorsum of each of nine young, crossbred, specific pathogen-free, female pigs, 20.6 +/- 1.9 kg in weight. A superactive charcoal paste (SAC) and/or a soap-and-water wash (SOAP) was applied to eight of the T-2-exposed sites on each animal. These treatments were applied at various times postexposure ranging from 5 to 65 min. The site that received T-2 alone served as a positive control. DMSO was applied to a tenth site on each pig as a negative control. Animals were killed 1, 3, or 6 days after treatment. Skin lesions were examined and graded grossly and histologically. No adverse systemic clinical signs were observed in any of the animals. Marked reddening and slight swelling of the T-2 toxin-treated positive control sites were present throughout the study. Ulceration of this site was first noted on Day 3. All therapeutic regimens effectively reduced lesion severity resulting from T-2 toxin application. Significant differences in relative effectiveness were also seen between treatments. In each significant pair, the ordering of mean lesion severity was SAC/SOAP less than SAC or SOAP and SOAP less than SAC. As a single treatment, SOAP appears to be more effective than SAC in reducing lesion severity. These results failed to provide unequivocal evidence of an additive therapeutic effect when SAC and SOAP were used sequentially on the same site.

PMID: 2612785 [PubMed - indexed for MEDLINE]

162. J Assoc Off Anal Chem. 1989 Sep-Oct;72(5):807-12.

Use of deuterated internal standards for quantitation of T-2 and HT-2 toxins in human blood by tandem mass spectrometry.

Pawlosky RJ, Mirocha CJ, Wen Y, Abbas HK.

University of Minnesota, Department of Plant Pathology, St. Paul 55108.

Deuterated acetyl derivatives (3-trideutero-acetyl-T-2 and 15-trideutero-HT-2) were prepared for use as internal standards for the quantitation of T-2 and HT-2 in blood by tandem mass spectrometry. The method used was multiple reaction monitoring (MRM), which essentially involves the selection of a parent ion for analysis followed by monitoring of the daughter ions generated by collision activated decomposition. The parent ions chosen for the trifluoroacetate derivative of T-2 and HT-2 were m/z+ 478 and 532, respectively. Both parents yield the same daughter ions, i.e., 180, 138, and 121. HT-2 and T-2 were added to blood extracts in amounts ranging from 1 to 20 ppb. The limit of detection is about 0.5 ppb with an effective detection limit of 1.0 ppb in a range of 1-20 ppb. The recovery is about 90%. This method can be used by veterinarians for purposes of diagnostics. It can be used for urine as well as blood.

PMID: 2808242 [PubMed - indexed for MEDLINE]

163. Toxicol Appl Pharmacol. 1989 Sep 1;100(2):201-7.

Anti-idiotypic antibodies against a monoclonal antibody specific for the trichothecene mycotoxin T-2.

Chanh TC, Huot RI, Schick MR, Hewetson JF.

Department of Virology and Immunology, Southwest Foundation for Biomedical Research, San Antonio, Texas 78284.

A BALB/c murine monoclonal antibody against the trichothecene mycotoxin T-2 was generated. The antibody, designated HD11, specifically bound T-2 mycotoxin. The binding of HD11 to T-2 conjugated to bovine serum albumin was inhibited by free T-2 toxin but not by the water-soluble heterocyclic guanidines saxitoxin and tetrodotoxin. The T-2 detection limit in an enzyme-linked immunosorbent assay with HD11 was in the nanogram range. The in vitro cytotoxicity of T-2, as measured by the inhibition of radiolabeled leucine uptake of the human epidermoid carcinoma Hep-2 and KB cell lines, was completely reversed by the addition of HD11. Rabbit anti-idiotypic antibodies specific for HD11 were generated and characterized.

PMID: 2789441 [PubMed - indexed for MEDLINE]

164. Food Chem Toxicol. 1989 Sep;27(9):591-8.

Chronic toxicity of nivalenol in female mice: a 2-year feeding study with Fusarium nivale Fn 2B-moulded rice.

Ohtsubo K, Ryu JC, Nakamura K, Izumiyama N, Tanaka T, Yamamura H, Kobayashi T, Ueno Y.

Department of Clinical Pathology, Tokyo Metropolitan Institute of Gerontology, Japan.

Groups of 42 7-wk-old female C57BL/6CrSlc SPF mice were fed diets containing 0, 6, 12 and 30 ppm nivalenol (NIV) for 2 years. Body-weight gain was reduced in all treated groups of animals and feed efficiency was reduced, significantly so, in the high-dose group. The absolute weights of the liver in the 30-ppm group, and of the kidneys in the 12- and 30-ppm groups were significantly reduced, compared with those of the controls. When expressed relative to brain weight there was a reduction in the kidney weight of the 12-ppm NIV group only. Some leucopenia was seen in the treated mice, particularly in the 30-ppm group, although this was not statistically significant, and there were dose-dependent increases in the serum concentrations of alkaline phosphatase and non-esterified fatty acids. No tumours attributable to NIV were found in any of the experimental groups. Naturally occurring tumours, mostly lymphomas, were of similar incidence in all groups, but developed later and appeared to grow more slowly in the mice of the 30-ppm group than in those of other groups. The incidence of amyloidosis, particularly in the small intestine, was low in the two higher dose groups compared with that in the control group. The mortality rate of the 30-ppm NIV group was lower than that of the control group and this may be partly due to the lower tumour incidence in the earlier period and partly due to the lower incidence of amyloidosis.

PMID: 2530144 [PubMed - indexed for MEDLINE]

165. Toxicol Lett. 1989 Jul;48(1):49-56.

Comparison of the toxicity of two trichothecenes applied topically to brain and liver of rats.

Bergmann F, Yarom R, Yagen B.

Department of Pharmacology, School of Pharmacy, Hebrew University-Hadassah Medical School, Jerusalem, Israel.

T-2 toxin has been found previously to be markedly more toxic upon intracerebral than upon systemic administration. In order to study the generality of this difference, we have applied to brain and liver of albino rats two different types of trichothecenes: T-2 toxin as a representative of 'simple' and myrotoxin B as a representative of 'macrocyclic' members of this series. Myrotoxin B, when applied intracerebrally, was about 100 times more poisonous than T-2 toxin. In contrast, upon intrahepatic injection both compounds exhibited similar degrees of toxicity. The different behavior of the two trichothecenes in the organs tested may be due to local metabolic factors.

PMID: 2749779 [PubMed - indexed for MEDLINE]

166. Am J Vet Res. 1989 Jun;50(6):942-4.

Effects of testosterone on the prevention of T-2 toxin-induced adrenocortical necrosis in mice.

Thurman JD, Creasia DA, Trotter RW.

Division of Pathology, US Army Medical Research Institute of Infectious Diseases, Frederick, MD 21701-5011.

To evaluate the effect of exogenous testosterone on the development of T-2 toxin-induced necrosis of adrenal glands, mice were allotted to 3 treatment groups. Each treatment group contained castrated male, and castrated and sexually intact female mice. Each mouse in group 1 was given 0.16 mg testosterone propionate at 48-hour intervals for a total of 12 injections, group-2 mice were given similar injections of only the vehicle, and group-3 mice were given no treatment. Twenty-four hours after the last injection, the mice in all 3 groups were exposed for 10 minutes to an aerosol of T-2 toxin. All mice alive at 24 hours after exposure were euthanatized and the adrenal glands and thymuses were examined histologically. Necrosis of the adrenal cortex was not found in any of the mice given preexposure treatment with exogenous testosterone, whereas all mice given vehicle only or no treatment had T-2 toxin-induced necrosis of the inner portion of the adrenal cortex. Lymphocytolysis in the cortex of the thymus confirmed that each mouse of all 3 treatment groups had experienced systemic mycotoxicosis. The uniform severity of the lesion in all mice suggests that the thymus was not protected by exogenous testosterone administration or by the castration status of the mice. We propose that T-2 toxin-induced adrenal necrosis in mice is prevented by the presence of testosterone.

PMID: 2764347 [PubMed - indexed for MEDLINE]

167. Food Chem Toxicol. 1989 Jun;27(6):361-8.

Dysregulation of IgA production and IgA nephropathy induced by the trichothecene vomitoxin.

Pestka JJ, Moorman MA, Warner RL.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing 48824.

The effect of dietary exposure to vomitoxin on serum immunoglobulin A (IgA) was evaluated in the B6C3F1 mouse. Levels of serum IgA were elevated maximally in mice fed 25 ppm vomitoxin in comparison with levels in mice fed 2, 10 or 50 ppm vomitoxin. Significant increases were detectable after as few as 4 wk in mice fed 25 ppm vomitoxin, and IgA levels were increased more than 17-fold after 24 wk of toxin exposure. Serum IgA also exhibited a marked shift from primarily monomeric IgA to primarily polymeric IgA during vomitoxin treatment. Serum IgG and IgM decreased in treated mice, suggesting that the effect was isotype-specific. Elevated serum IgA was not observed in mice when control diet was fed at levels equivalent to those consumed by vomitoxin-treated mice, which exhibited feed refusal. IgA production was significantly increased in both spontaneous and mitogen-stimulated splenocyte cultures from mice exposed to vomitoxin in comparison with cultures prepared from ad lib. or feed-restricted controls. Immunofluorescence staining revealed marked accumulation of mesangial IgA and electron microscopy showed electron-dense deposits in the glomeruli of vomitoxin-treated mice but not in those of controls. Dysregulation of IgA production and accumulation of glomerular IgA as observed in this study were highly analogous to the characteristics of human IgA nephropathy, the most common form of glomerulonephritis worldwide.

PMID: 2676788 [PubMed - indexed for MEDLINE]

168. Toxicol Appl Pharmacol. 1989 Mar 1;97(3):512-24.

Reduction of anguidine toxicity in rats by atropine and methylatropine.

Malarkey DE, Conner BH, Rogers AE, Conner MW, Newberne PM.

Department of Pathology, Boston University School of Medicine, Mallory Institute of Pathology, Massachusetts.

Lethality of anguidine (diacetoxyscirpenol) in rats and mice appears to be the result of primary or secondary cardiovascular collapse and to be related to severe tissue destruction in the gut and elsewhere. Experiments were performed in rats to examine the effect on anguidine lethality of treatment with several agents that alter gut function or toxic effects of other chemicals in the gut. Administration of atropine sulfate or methylatropine nitrate by sc injection to rats immediately following administration of an LD50 of anguidine and again 4 hr later gave modest but significant protection against anguidine lethality. The drugs were effective over a range of doses between 2.5 and 20 mg/kg, without a clear dose response, and probably were effective at doses lower than 2.5 mg/kg. S-Adenosylmethionine, 25 mg/kg, given to rats at the time of administration of an LD50 of anguidine and again 4 hr later gave some evidence of protection also. Semiquantitative evaluation of pathologic changes in the small intestine, a target of anguidine, indicated partial protection by atropine sulfate against anguidine toxicity at that site. Atropine-treated rats showed less severe damage, earlier resolution of damage, or both.

PMID: 2609347 [PubMed - indexed for MEDLINE]

169. Physiol Behav. 1989 Mar;45(3):501-6.

Effects of T-2 toxin on saccharin aversion and food consumption in adult rats.

Wellman PJ, Rowe LD, Clark DE, Cockroft RD.

Department of Psychology, Texas A&M University, College Station 77843.

The present experiment used a saccharin aversion paradigm to evaluate the potential aversive action of T-2 toxin, a trichothecene mycotoxin that induces emesis and weight loss. Adult male rats were fed either a control diet or a diet adulterated with 640 ppm lithium chloride (positive control) or with 2.5, 5.0 or 10.0 ppm T-2 toxin and given access to a 0.1% saccharin solution and to tap water during four training days. The rats were then shifted to the control diet during three extinction days. Moderate saccharin aversion induced by the positive control diet and the 5.0 and 10.0 ppm T-2 diets was apparent on the third day of exposure and the aversion to the saccharin solution abated during the extinction trials. Saccharin aversion was evident at levels of T-2 toxin that did not induce obvious tissue pathology.

PMID: 2547222 [PubMed - indexed for MEDLINE]

170. Mycopathologia. 1989 Mar;105(3):143-51.

Mycotoxins produced by toxic Fusarium isolates obtained from agricultural and nonagricultural areas (Arctic) of Norway.

Abbas HK, Mirocha CJ, Gunther R.

Department of Plant Pathology, School of Medicine, University of Minnesota, St. Paul 55108.

Twenty-five isolates of F. acuminatum, 38 of F. avenaceum, 1 of F. culmorum, 31 of F. oxysporum and 56 of F. sambucinum were obtained in 1983, 1984 and 1986 from cereal grains and soil from various parts of Norway. The isolates were grown on an autoclaved Uncle Ben's parboiled rice medium and examined for production of trichothecenes and other toxins and for toxicity in rat feeding tests. F. culmorum N46C(2) and Fusarium sambucimum 45-86-A produced zearalenone (F-2) 864 and 665 ppm, respectively and caused uterine enlargement in rats. Most of these isolates produced no known trichothecene mycotoxins that could account for the toxicity that was demonstrated in the rat feeding tests. All but F. avenaceum N26B produced fusarin C (1.5 ppm) but caused no toxic effects in rat feeding test. None of the isolates produced fusarochromanone (TDP-1). Thirteen isolates of F. acuminatum, 16 of F. avenaceum, 14 of F. oxysporum and 3 of F. sambucinum produced a cytotoxic factor which we named HM-8. One isolate of F. avenaceum, 12 of F. oxysporum and 46 of F. sambucinum produced a hemorrhagic factor which we named H-1 (wortmannin). Twenty isolates of F. acuminatum, 22 of F. avenaceum, 17 of F. oxysporum and 1 of F. sambucinum produced moniliformin. Four isolates of F. acuminatum, 9 of F. avenaceum, 25 of F. oxysporum and 52 of F. sambucinum caused death to rats. Three isolates of F. avenaceum, 19 of F. oxysporum and 47 of F. sambucinum induced hemorrhage in various organs. All isolates caused decreased weight gain, relative to the control diets.

PMID: 2527336 [PubMed - indexed for MEDLINE]

171. Cancer Chemother Pharmacol. 1989;24(4):264-7.

The cytotoxicity of T-2 toxin and related 12,13-epoxytrichothecenes to Adriamycin-sensitive and -resistant P388 leukemia cells.

Ramu A, Yagen B, Ramu N.

Department of Radiation and Clinical Oncology, Hadassah University Hospital, Jerusalem, Israel.

The cytotoxicity of T-2 toxin and related trichothecenes was studied in Adriamycin-sensitive and -resistant P388 leukemia cells in vitro. The structure-activity relationship indicated that a free hydroxyl in the C-3 position contributed to the activity. Free hydroxyls at the 4, 8, and 15 positions interfered with the activity, and their estrification resulted in improved cytotoxicity. The cytotoxic activity of these trichothecenes did not seem to be related to their degree of lipophilicity. Adriamycin-resistant P388 cells were cross-resistant to the trichothecenes, and this resistance could be circumvented by verapamil.

PMID: 2752509 [PubMed - indexed for MEDLINE]

172. Am J Vet Res. 1988 Dec;49(12):2147-50.

Effects of T-2 mycotoxin on tumor susceptibility in mice.

Corrier DE, Norman JO.

USDA, Veterinary Toxicology and Entomology Research Laboratory, College Station, TX 77841.

The effect of Fusarium-produced T-2 toxin on tumor growth was evaluated in ICR, CFW, and C57B6/6 mice inoculated with murine sarcoma, Ehrlich ascites carcinoma, or B16F1 melanoma tumor cell lines. Mice were given T-2 toxin intragastrically either at the rate of 2 mg of toxin/kg of body weight daily for 5 days or a single dosage of 4 mg of toxin/kg and were inoculated SC with tumor cells 1 or 2 days after administration of toxin. Tumor growth was assessed 15 to 41 days after tumor challenge by determining the frequency of tumor development and tumor weights. Significant increases in the frequency of development of murine sarcoma (P less than 0.005), Ehrlich ascites carcinoma (P less than 0.01), and B16F1 melanoma tumors (P less than 0.05) were detected in toxin-treated mice, compared with control mice. Murine sarcoma and B16F1 melanoma tumor weights also were significantly (P less than 0.01) higher in toxin-treated mice. The effect of T-2 toxin on tumor growth was more marked after 5 daily treatments than after a single dose.

PMID: 3239851 [PubMed - indexed for MEDLINE]

173. Am J Vet Res. 1988 Dec;49(12):2151-60.

Pathologic, hematologic, and serologic changes in rabbits given T-2 mycotoxin orally and exposed to aerosols of Aspergillus fumigatus conidia.

Niyo KA, Richard JL, Niyo Y, Tiffany LH.

USDA, National Animal Disease Center, Ames, IA 50010.

The influence of immunosuppression by T-2 mycotoxin on the fungal disease aspergillosis was investigated in rabbits. Four groups of rabbits (groups 1A, 1B, 3A, and 3B) were given 0.5 mg of T-2 toxin/kg of body weight/day, PO; in addition, rabbits of groups 3A and 3B were exposed to aerosols of Aspergillus fumigatus conidia from days 7 through 16. Rabbits of groups 2A and 2B were exposed to A fumigatus aerosols, but were not given T-2 toxin, and rabbits of group 0 served as controls. Two rabbits of group 1A, 1 rabbit of group 1B, and 1 rabbit of group 3A died before scheduled necropsy. Rabbits of groups 1A, 2A, and 3A were killed and necropsied on day 17, and the remaining rabbits (groups 0, 1B, 2B, and 3B) were killed and necropsied on day 28. Changes caused by T-2 toxin included leukopenia, marginal anemia, and increased number of and morphologic changes in nucleated erythrocytes by day 21, followed by a regenerative hematologic response. Serum alkaline phosphatase and sorbitol dehydrogenase activities and antibody response to A fumigatus (as measured by an indirect hemagglutination test) were decreased by T-2 toxin ingestion. Rabbits with aspergillosis had leukocytosis, increased PCV, and increased antibody response to A fumigatus. Histologic lesions consisting of centrilobular hepatocellular swelling, portal and periportal fibrosis, and lymphocyte necrosis and/or depletion within secondary lymphoid tissue were observed in most rabbits treated with T-2 toxin. Normal defense mechanisms against A fumigatus infection were compromised by T-2 treatment, as evidenced by the severity and extent of lung lesions, greater number of hyphal elements observed, and greater number of colonies of A fumigatus isolated from rabbits of groups 3A and 3B. There were no significant changes in group-0 rabbits.

PMID: 3071196 [PubMed - indexed for MEDLINE]

174. Am J Vet Res. 1988 Nov;49(11):1928-31.

Mycotoxicosis caused by aerosolized T-2 toxin administered to female mice.

Thurman JD, Creasia DA, Trotter RW.

Division of Pathology, US Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, MD 21701-5011.

Thymus, spleen, adrenal glands, and small intestine of female mice exposed to aerosolized T-2 mycotoxin were examined at postexposure hours (PEH) 0.25, 1, 2, 4, 6, 9, 12, and 24. Lymphocyte necrosis was observed at PEH 1 in the thymus, spleen, and lamina propria and Peyer patches of the small intestine. Necrosis of small intestinal crypt epithelial cells was observed at PEH 2, and necrosis of parenchymal cells and increased number of neutrophils were seen in sinusoids of the adrenal cortex at PEH 4. These results indicated that the earliest microscopic evidence of T-2 mycotoxicosis after aerosol exposure was necrosis of lymphocytes in the thymus, spleen, and lamina propria and Peyer patches of the small intestine.

PMID: 3247917 [PubMed - indexed for MEDLINE]

175. Toxicol Lett. 1988 Nov;44(1-2):191-200.

Synergistic interaction between the trichothecene T-2 toxin and Salmonella typhimurium lipopolysaccharide in C3H/HeN and C3H/HeJ mice.

Tai JH, Pestka JJ.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing 48824-1224.

The capacity of the trichothecene T-2 toxin to alter resistance to bacterial lipopolysaccharide (LPS) was examined in the mouse. Both LPS-susceptible (C3H/HeN) and LPS-resistant (C3H/HeJ) mouse strains exhibited markedly enhanced mortality when a single oral dose of T-2 toxin (1 mg/kg) was coadministered with a subacute i.p. dose of Salmonella typhimurium LPS. In the absence of LPS, T-2 toxin did not cause lethal effects when administered at this level. LD50 values for LPS decreased by 14-fold and 4.5-fold upon co-administration with T-2 toxin (1 mg/kg) in C3H/HeN and C3H/HeJ mice, respectively. Increased mortality was accompanied by an impaired splenic response to LPS in C3H/HeN mice. C3H/HeN mice pretreated with a sublethal dose of LPS 24 h prior to T-2 toxin administration also exhibited significantly increased susceptibility to T-2 toxin. Histopathological assessment revealed that the liver and spleen of mice exposed to T-2 toxin and LPS exhibited extensive cell death as compared to control mice treated with T-2 toxin or LPS only. The results suggest that bacterial LPS and trichothecenes such as T-2 toxin interact synergistically. This interaction may contribute to increased mortality that has been observed previously in animals challenged with Salmonella and T-2 toxin.

PMID: 3055430 [PubMed - indexed for MEDLINE]

176. Food Addit Contam. 1988 Oct-Dec;5(4):629-39.

A sensitive enzyme-linked immunosorbent assay for detection of T-2 toxin with monoclonal antibodies.

Chiba J, Kawamura O, Kajii H, Ohtani K, Nagayama S, Ueno Y.

Department of Pathology, National Institute of Health, Tokyo, Japan.

Six monoclonal antibodies (mAbs, T-2.1, 2, 3, 4, 5, 6) which react with a trichothecene mycotoxin, T-2 toxin (T-2), were prepared. All antibodies specifically reacted with T-2 but less (0.5% of T-2) with the metabolites such as HT-2 toxin and 3'-hydroxy-T-2 toxin. Significant but less than 0.02% cross-reactivity was observed with T-2 triol, 3'-hydroxy-HT-2 toxin and neosolaniol. No significant reaction with other trichothecenes such as deoxynivalenol, nivalenol, fusarenon-X, crotocin, or roridin A was observed. The least detectable amount of T-2 with the best mAb T-2.1 was 2.5 pg T-2 per assay. This specific and highly sensitive assay for T-2 was applied for the quantitation of T-2 in wheat flour spiked with mycotoxin, with combination of a simple extraction procedure.

PMID: 3192013 [PubMed - indexed for MEDLINE]

177. Am J Vet Res. 1988 Oct;49(10):1766-73.

Effects of T-2 mycotoxin ingestion on phagocytosis of Aspergillus fumigatus conidia by rabbit alveolar macrophages and on hematologic, serum biochemical, and pathologic changes in rabbits.

Niyo KA, Richard JL, Niyo Y, Tiffany LH.

USDA, Agricultural Research Service, National Animal Disease Center, Ames, IA 50010.

Rabbits were given T-2 mycotoxin orally at 0, 0.25, 0.5, and 0.75 mg/kg of body weight/day for 21 days. Only rabbits in the 0.75 mg/kg/day group (4 of 5 rabbits) died. Alveolar macrophages were harvested on day 22 and used for in vitro phagocytosis of killed Aspergillus fumigatus conidia. Cultures included sera from untreated rabbits or rabbits treated with T-2. Phagocytosis was significantly (P less than 0.01) reduced in cultures that used serum from rabbits treated with 0.5 mg of T-2/kg/day and alveolar macrophages from untreated rabbits or rabbits treated with T-2. There was little reduction in phagocytosis when alveolar macrophages from rabbits treated with T-2 and normal serum were used. Ingestion of 0.5 mg of T-2 toxin/kg/day significantly (P less than 0.05) reduced weight gain, serum alkaline phosphatase activity, serum sorbitol dehydrogenase activity, and serum bacteriostasis. Similar changes were found in the 0.75 mg/kg/day group, as well as a significant (P less than 0.05) reduction in PCV, total WBC, and differential leukocyte counts. Neutrophil counts decreased, but not significantly (0.05 less than P less than 0.10). Significant changes were not detected in alanine transaminase activity, aspartate transaminase activity, blood urea nitrogen concentration, or complement hemolytic activity. Histopathologic changes consisting of centrilobular hepatocellular swelling, mild portal and periportal fibrosis and lymphocyte necrosis within secondary lymphoid tissues developed in most rabbits treated with T-2. Thymic atrophy, bile duct reduplication, and lymphocyte depletion of secondary lymphoid tissues developed in the group given 0.75 mg/kg/day.(ABSTRACT TRUNCATED AT 250 WORDS)

PMID: 3056139 [PubMed - indexed for MEDLINE]

178. Zhonghua Zhong Liu Za Zhi. 1988 Sep;10(5):339-41.

[Papilloma of forestomach induced by Fusarium T-2 toxin in mice].

[Article in Chinese]

Yang S.

Cancer Institute, Chinese Academy of Medical Sciences, Beijing.

T-2 toxin is one of the important representatives of trichothecin metabolites of Fusarium species. Various proliferative changes in epithelia of forestomach including papillomas were induced in mice after prolonged feeding of T-2 toxin by intubation at 0.1 mg/kg, 3 times a week for 25 weeks. The incidences of hyperkeratosis, papillary hyperplasia, moderate dysplasia and papilloma were 82.9%, 28.6%, 42.9% and 14.3% respectively. The earliest papilloma in forestomach of mice occurred as early as 6th week of the experiment. While in forestomach of mice in the control group, only 4.20% hyperkeratosis and 4.2% simple hyperplasia were found, no papillary hyperplasia or papilloma occurred. The above results indicate that T-2 toxin has a selective tumorigenic effect on the forestomach which is actually the extension of the esophagus in mice. These findings may give important hint to the study of human esophageal carcinogenesis.

PMID: 3248499 [PubMed - indexed for MEDLINE]

179. Cancer Lett. 1988 Aug 30;41(3):287-94.

Acute and chronic effects of diacetoxyscirpenol on cell replication in rat esophagus and stomach.

Craddock VM, Hill RJ, Henderson AR.

MRC Toxicology Unit, Carshalton, Surrey, U.K.

The effect of the mycotoxin diacetoxyscirpenol (DS) on the upper alimentary tract was studied on account of the association between the consumption of food contaminated by Fusaria and esophageal cancer. Previously it had been shown that a single high dose of DS induced basal cell replication in esophagus and in squamous and glandular stomach. To assess the significance of this effect in relation to the levels of exposure likely to be encountered by man and agricultural animals, it was essential to examine the dose response relationship. Also, the long-term effect of repeated intubations of DS, and of chronic feeding of DS at 10 ppm in the diet, was studied. Intubation of progressively lower doses of DS produced a decreasing effect on replication in esophagus and stomach, but at 0.06 mg/kg replication in squamous and glandular stomach was still more than in the control animals. Intubation repeated weekly for 6-8 weeks produced no detectable change in esophagus or stomach in the surviving animals which were killed at 9 months. When DS was fed in the diet, there was marked hyperplasia in the squamous stomach of two of the four animals which survived for 9 months. These results suggest that DS per se is not carcinogenic for esophagus or for stomach, and that exposure to occasional high doses does not cause persisting abnormalities in replication. However, repeated exposure to high doses would cause repeated periods of hyperplasia, and chronic exposure in some animals could result in continuing hyperplasia. Any increase in replication is likely to promote cancer by increasing the vulnerability of the gastric and esophageal mucosa to carcinogens.

PMID: 3409207 [PubMed - indexed for MEDLINE]

180. Food Chem Toxicol. 1988 Aug;26(8):691-8.

Impaired murine resistance to Salmonella typhimurium following oral exposure to the trichothecene T-2 toxin.

Tai JH, Pestka JJ.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing 48824-1224.

On orally exposing Salmonella-resistant C3H/HeN mice to the trichothecene T-2 toxin (1 mg/kg body weight), challenging with Salmonella typhimurium, and continuing to dose with T-2 toxin on alternate days for 3 wk, the LD50 for the organism decreased by five orders of magnitude, in comparison with control mice not treated with T-2 toxin. In the absence of S. typhimurium, T-2 toxin did not cause lethal effects when administered at this level. Increased mortality in response to S. typhimurium challenge was dependent on T-2 toxin dose in the range 0 to 1 mg/kg for this regimen. The toxin did not significantly affect intestinal infection but did increase splenic counts in mice challenged with a range of S. typhimurium doses and also accelerated body-weight loss in infected animals. Mice challenged with the organism exhibited similar mortality when T-2 toxin treatment was begun 1 day prior to infection or at 5 or 9 days after infection. A time-related decrease in mortality, relative to that found for the standardized co-challenge described above, was observed when T-2 toxin administration was begun at 9, 13 or 23 days after infection. The results indicated that, depending on the challenge dose of the organism, both early and late phase acquired immune response to S. typhimurium could be impaired by T-2 toxin. Markedly enhanced susceptibility to gram-negative bacterial infection is another manifestation of trichothecene toxicity and may be an important aetiological factor in animal health problems that are associated with these mycotoxins.

PMID: 3058560 [PubMed - indexed for MEDLINE]

181. Arch Toxicol. 1988 Jan;61(3):241-4.

Dermal toxicity of Fusarium toxins in combinations.

Bhavanishankar TN, Ramesh HP, Shantha T.

Department of Microbiology and Sanitation, Central Food Technological Research Institute, Mysore, India.

T 2 toxin (T 2), diacetoxyscirpenol (DAS), fusarenon X (FX) and butenolide (Bd) at concentrations of 0.2, 0.3, 5 and 10 micrograms/site, respectively, were applied individually and in combinations on shaved skin of guinea pigs. Erythema and induration were observed on skin patches treated with the toxins. Increase in the thickness of stratum malpighii was the major histological change observed. Mild to moderate degeneration of fibrocytes and cellular infiltration were found in the corium of skin treated with FX, Bd, DAS and T 2. The order of toxicity of individual toxins was T 2 greater than DAS greater than FX greater than Bd. Combinations of T 2 + FX and T 2 + Bd resulted in antagonism, while DAS + FX and DAS + Bd caused synergism.

PMID: 3355369 [PubMed - indexed for MEDLINE]

182. Acta Vet Hung. 1988;36(1-2):37-41.

Effect of trichothecene mycotoxins (satratoxin H and T-2 toxin) on the lymphoid organs of mice.

Glávits R, Ványi A.

PMID: 3202049 [PubMed - indexed for MEDLINE]

183. Toxicon. 1988;26(10):923-30.

Cerebral toxicity of the trichothecene toxin T-2, of the products of its hydrolysis and of some related toxins.

Bergmann F, Soffer D, Yagen B.

Department of Pharmacology, Hebrew University-Hadassah Medical School, Jerusalem.

T-2 toxin and its metabolites (resulting from enzymatic hydrolysis by rat brain homogenate) were applied to the midbrain of albino rats, either in solid form or dissolved in dimethyl sulfoxide (DMSO). Solid implants of HT-2 toxin and of T-2 triol were lethal in the range of 10-20 micrograms per rat, i.e. similar to the effect of T-2 toxin itself. For four further trichothecenes, the following decreasing order of toxicities was found: T-2 tetraol = iso-T-2 toxin greater than T-2 tetraol tetraacetate greater than T-2 toxin acetate. Implants of the last compound were the least toxic in the present series of trichothecenes; its LD50 value was nearly ten times higher than that of T-2 toxin. A similar gradation of toxicity was observed upon intracerebral injection of the compounds dissolved in DMSO. Here the only exception was the markedly reduced toxicity of T-2 toxin itself. From these data, the role of free 3 alpha- and 4 beta-hydroxyl groups has been evaluated. For subcutaneous applications, the largest ratio of LD50 values was 5, i.e. for the pair T-2 triol-T-2 tetraol tetraacetate. Among the signs of central intoxication, convulsions, adipsia and aphagia were marked. Pathological changes in the brain tissue, mainly involving necrotic, hemorrhagic and inflammatory lesions at the sites of application, were similar for all trichothecenes tested in this study.

PMID: 3201481 [PubMed - indexed for MEDLINE]

184. Cancer Detect Prev. 1988;13(2):79-86.

Natural occurrence and clastogenic effects of nivalenol, deoxynivalenol, 3-acetyl-deoxynivalenol, 15-acetyl-deoxynivalenol, and zearalenone in corn from a high-risk area of esophageal cancer.

Hsia CC, Wu JL, Lu XQ, Li YS.

Department of Pathology, Chinese Academy of Medical Sciences, Beijing.

This is the first report of the natural coexistence of a group of Fusarium mycotoxins (nivalenol [NIV], deoxynivalenol [DON], 3-acetyl-deoxynivalenol [3-ADON], 15-acetyl-deoxynivalenol [15-ADON], and zearalenone [ZEN]) in corn from Linxian, China, an area with a high risk of esophageal cancer. Using thin layer chromatography (TLC), high pressure liquid chromatography (HPLC), and gas chromatography (GC), 107 corn samples from Linxian were analyzed. The average levels of NIV and DON were 757 +/- 707 (54-2,760) ng/g and 5,376 +/- 4,460 (360-12,670) ng/g, respectively, with 100% positivity in 24 corn samples consumed as staple food by esophageal cancer patients and their families. Other corn samples collected from five villages in Linxian at different seasons in 1984-1986 also revealed high levels of NIV and DON contamination, with 100% positivity, suggesting that they are consistently and widely present in corn in that area. Levels of 3-ADON and 15-ADON in Linxian corn were 113 +/- 57 and 495 +/- 538 ng/g, respectively. Crude extracts of corn samples collected from esophageal cancer patients' families and the HPLC-purified NIV and DON fractions induced significant chromosome aberrations in V79 cells. Pure toxins of NIV, DON, T-2, and 3-ADON also induced chromosome aberrations in V79 cells at very low concentrations (ng levels/ml medium). Cytotoxic effects were observed at slightly higher concentrations. The levels and kinds of trichothecenes were in positive co-relation with the incidence of esophageal cancer. The data suggest that trichothecenes in food may possibly be associated with esophagitis and esophageal cancer in Linxian.

PMID: 2977296 [PubMed - indexed for MEDLINE]

185. Fundam Appl Toxicol. 1987 Oct;9(3):595-7.

Effect of fusarochromanone and T-2 toxin on articular chondrocytes in monolayer culture.

Wright GC Jr, Marasas WF, Sokoloff L.

Department of Pathology, State University of New York, Stony Brook 11794.

The effect of fusarochromanone and T-2 toxin on DNA synthesis and radio-sulfate incorporation by rabbit articular chondrocytes was studied in monolayer culture. T-2 toxin reduced DNA more than 50% at 5 x 10(-9) M; fusarochromanone caused small but progressive decrements over a range of 5 x 10(-8) to 10(-6) M. These actions are not specific for chondrocytes. The findings lend no support to the hypothesis that fusarochromanone, at least in unmodified form, is the etiologic agent in Kashin-Beck disease.

PMID: 3692017 [PubMed - indexed for MEDLINE]

186. Am J Vet Res. 1987 Oct;48(10):1516-9.

Listeriosis in diacetoxyscirpenol-treated mice.

Ziprin RL, Corrier DE.

Veterinary Toxicology and Entomology Research Laboratory, USDA, College Station, TX 77841.

Mice were treated with the trichothecene mycotoxin diacetoxyscirpenol (DAS) and subsequently were inoculated intraperitoneally with Listeria monocytogenes. The effect of the mycotoxin on the course of the infection was monitored by observing the resultant mortality and the bacterial content of the spleens from inoculated mice. Mice given 3 mg of DAS/kg of body weight, PO, at days -2 and -1 before inoculation had increased mortality and splenic Listeria counts. In these mice, thymus weights were reduced, and lymphocytes were depleted from the thymus cortex and from splenic lymphoid follicles and periarteriolar lymphoid sheaths. A single dose of 4 mg of DAS/kg given on day 6 before challenge exposure did not affect mortality compared with that in nontreated controls. Mice treated with DAS and subsequently inoculated with Listeria had significantly (P = 0.006) increased neutrophil populations compared with Listeria-infected control mice.

PMID: 3674563 [PubMed - indexed for MEDLINE]

187. Exp Mol Pathol. 1987 Oct;47(2):143-53.

T-2 toxin effect on rat aorta: cellular changes in vivo and growth of smooth muscle cells in vitro.

Yarom R, Sherman Y, Bergmann F, Sintov A, Berman LD.

Department of Pathology, School of Pharmacy, Hebrew University, Hadassah Medical School, Jerusalem, Israel.

Rats were injected intraperitoneally with T-2 toxin and their aortas were studied by light and electron microscopy. The growth of smooth muscle cell explants taken from the tunica media of aortas of similarly treated animals was observed. A single large dose (2 mg/kg) or four injections of 0.3 mg/kg T-2 toxin caused damage and occasional necrosis of endothelial cells, accumulation of basement membrane-like material in the intima, and swelling and activation of smooth muscle cells in the tunica media. Three or more weeks after the last injection of 0.3 mg/kg T-2 toxin the endothelial cells were normal but an excess of fragmented intimal basement membrane-like material persisted and smooth muscle cells were still activated. Outgrowths from explants of aortic tunica media taken within 1 week of the last dose of T-2 toxin showed marked inhibition of smooth muscle cell growth. Three or more weeks after the toxin, the explants showed significantly increased outgrowths. These findings suggest that T-2 toxin causes early endothelial and smooth muscle cell injury accompanied by inhibition of smooth muscle cell growth in culture. This is followed by stimulation of the proliferative capacity of smooth muscle cells in vitro. If a similar mechanism is operative in vivo, it could explain the chronic vascular changes observed after limited exposure to T-2 toxin.

PMID: 3653343 [PubMed - indexed for MEDLINE]

188. Food Chem Toxicol. 1987 Aug;25(8):593-601.

Effects of low-level long-term oral exposure to T-2 toxin in CD-1 mice.

Schiefer HB, Rousseaux CG, Hancock DS, Blakley BR.

In a 16-month feeding study male and female CD-1 mice received semi-synthetic diets containing 0, 1.5 or 3.0 ppm T-2 toxin. Feed consumption, body-weight gains, clinical findings (including haematological examinations at 16 months) and the development of external lesions were recorded. At 3, 6, 12 and 16 months, animals were killed for assessment of their immune function. Disease-related deaths did not differ among groups. Histological examination of all organs revealed statistically significant differences from controls in the incidence of pulmonary adenomas and hepatic adenomas in the 3.0-ppm group. Other treatment-related findings were an increased prevalence of epithelial hyperplasia in the forestomach of animals treated with T-2 toxin, and increased heart weights in treated male mice. T-lymphocyte-dependent humoral immunity tests did not reveal treatment effects and haematology revealed no particular trends. It is concluded that chronic feeding of T-2 toxin at low levels is not immunosuppressive but has a carcinogenic or tumour-promoting effect in mice.

PMID: 3497853 [PubMed - indexed for MEDLINE]

189. Fundam Appl Toxicol. 1987 Jul;9(1):41-9.

The toxicity of T-2 toxin in swine following topical application. I. Clinical signs, pathology, and residue concentrations.

Pang VF, Swanson SP, Beasley VR, Buck WB, Haschek WM.

T-2 toxin at 0 or 15 mg/kg in 0.75 ml dimethyl sulfoxide was topically applied to 11- to 12-week-old specific-pathogen-free derived crossbred female pigs. Animals were killed on Days 1, 3, 7, or 14 after treatment. Clinical signs and morphologic changes in the skin and internal organs, as well as the residual concentrations of T-2 toxin and its metabolites in plasma, bile, urine, skin, and subcutaneous tissue, were examined. The T-2-treated pigs had signs of lethargy, anorexia, posterior weakness or paresis, and persistent fever. The skin at the site of application was red and swollen initially and progressively became dark red and then purple. By Day 7, at the margin of the exposed area, clefts had formed and were covered by serosanguinous exudate. By Day 14, the affected skin was focally separated from the underlying tissue and covered by a thick scab. The initial skin lesions were characterized as a spongiotic dermatitis and were located mainly in the dermal papillae and stratum germinativum of the epidermis. These lesions progressed to a locally extensive necrotizing dermatitis between Days 3 and 7 that was still evident at Day 14. Healing began on Day 7 and was more prominent on Day 14. Morphologic changes in the internal organs were minimal. They consisted of necrosis of single cells in the follicles of lymphoid tissues and in the exocrine pancreas.(ABSTRACT TRUNCATED AT 250 WORDS)

PMID: 3622962 [PubMed - indexed for MEDLINE]

190. Am J Vet Res. 1987 Jun;48(6):998-1002.

T-2 toxin-enhanced resistance against listeriosis in mice: importance of gastrointestinal lesions.

Ziprin RL, Corrier DE, Ziegler HK.

The role of T-2 toxin-induced gastrointestinal lesions in T-2 toxin-enhanced resistance to listeriosis in mice was evaluated. The T-2 toxin-induced lesions did not cause a starvation effect sufficient to enhance resistance to listeriosis. Administration of polymyxin E markedly reduced the gram-negative intestinal microflora and did not eliminate the toxin-induced resistance to listeriosis. The T-2 toxin did not cause an increased expression of Ia surface antigens on peritoneal macrophages. Thus, toxin-induced anorexia and starvation or absorption of gram-negative intestinal bacteria and endotoxins through toxin-induced gastrointestinal lesions did not account for the enhancing effect of T-2 toxin on resistance to Listeria monocytogenes infection in mice.

PMID: 3111316 [PubMed - indexed for MEDLINE]

191. Fundam Appl Toxicol. 1987 Apr;8(3):298-309.

Experimental T-2 toxicosis in swine. III. Morphologic changes following intravascular administration of T-2 toxin.

Pang VF, Lorenzana RM, Beasley VR, Buck WB, Haschek WM.

The gross and microscopic changes in swine following a single intravascular (iv) dose of T-2 toxin are described and evaluated quantitatively. T-2 toxin, in 70% ethanol, was given iv at 0 (5 pigs), 0.6 (5 pigs), 1.2 (1 pig), 4.8 (5 pigs), or 5.4 (2 pigs) mg/kg to 40 to 60 kg female crossbred pigs. The 4.8 and 5.4 mg/kg group pigs died between 5 and 10.5 hr after treatment, while the 0, 0.6, and 1.2 mg/kg pigs were killed at 24, 24, and 12 hrs after treatment, respectively. Morphologic examination was performed at the gross and light microscopic levels. In addition, a quantitative evaluation of microscopic changes present in lymphoid tissues and intestinal tract was performed using a semiquantitative scoring system. Gross lesions in the T-2-treated pigs consisted of edema, congestion, and hemorrhage of the lymph nodes and pancreas; congestion and hemorrhage of the gastrointestinal mucosa, subendocardium, adrenal gland, and meninges; and edema of the gall bladder. Histologic examination confirmed the gross observations. Additional microscopic lesions included widespread degeneration and necrosis of the lymphoid tissues as well as of the surface and crypt epithelium of the gastrointestinal mucosa; mild scattered necrosis of pancreatic acinar cells, myocardium, bone marrow cells, adrenal cortical cells, and tubular epithelium of renal medulla; and mild interstitial pneumonia. A dose-dependent increase in lesion severity was observed except for the pancreatic lesion which was slightly more apparent in the pigs from the 0.6 mg/kg group. These findings indicate that T-2 toxin-induced lesions in the lymphoid tissues and gastrointestinal tract of pigs are similar to those of other species the pancreas and heart should be considered as additional target organs in the pig, and both rapidly dividing cells and those with little or no turnover are damaged by T-2 toxin.

PMID: 3569701 [PubMed - indexed for MEDLINE]

192. Toxicol Lett. 1987 Mar;36(1):15-22.

Cardiovascular pathology induced by passive transfer of splenic cells from syngeneic rats treated with T-2 toxin.

Sherman Y, More R, Yagen B, Yarom R.

Mononuclear cells were separated from spleens and lymph nodes of Lewis rats treated 5 weeks previously with repeated small doses of T-2 toxin or solvent only. The cells from each site were then injected intraperitoneally into 4 groups of syngeneic Lewis rats. The animals injected with spleen cells from T-2 toxin-treated donors developed marked cardiovascular changes which were similar to those due to T-2 toxin itself. Rats injected with lymph node cells as well as those given each kind of cell from solvent-treated donors showed only occasional mild vascular changes. The changes seen after splenic cell transfer may be due to superinduction of interleukin 2 by T-2 toxin.

PMID: 3494329 [PubMed - indexed for MEDLINE]

193. J Natl Cancer Inst. 1987 Mar;78(3):419-23.

Effects of tumor promoters and cocarcinogens on growth and differentiation of cultured human esophageal epithelial cells.

Sasajima K, Willey JC, Banks-Schlegel SP, Harris CC.

The acute effects of 12-O-tetradecanoylphorbol-13-acetate [(TPA) CAS: 56937-68-9], T-2 toxin (CAS: 21259-20-1), capsaicin (CAS: 404-86-4), cigarette smoke condensate (CSC), and ethanol (CAS: 3807-77-0) were examined in secondary cultured human esophageal epithelial cells in serum-free LHC-8 medium. Effects were evaluated by morphology and measurement of clonal growth rate (population doublings per day), cross-linked envelope (CLE) formation, and the enzymatic activities of ornithine decarboxylase (ODC) and plasminogen activator (PA). All compounds tested were inhibitory to clonal growth; concentrations causing 50% growth inhibition were estimated as 10 nM TPA, 6 nM T-2 toxin, 40 microM capsaicin, 8 micrograms CSC/ml, 540 mM ethanol, and 0.8 microgram CSC/ml with 220 mM ethanol. None of the compounds tested induced CLE formation, although calcium ionophore (A23187) could induce CLE in at least 60% of the cells. TPA (10 and 100 nM) decreased the ODC activity of cells, and capsaicin (100 microM) induced ODC by 220%. TPA (1-100 nM) and capsaicin (100 microM) also induced PA activity. Slight increases in ODC activity by CSC (10 micrograms/ml), CSC (1 microgram/ml) with ethanol, and T-2 toxin (1 nM) were observed, but PA activity was not affected by these compounds. The results indicated that the response of human esophageal epithelial cells to TPA is both similar to and different from that reported for human epidermal and bronchial cells in vitro. Enhancement of PA activity and decrease in ODC by TPA are found in all three human epithelial cell types. However, these changes are not associated in esophageal cells with increased CLE formation as reported in studies with the use of bronchial and epidermal epithelial cells. The results from these acute studies provide the basis for designing in vitro carcinogenesis investigations using these agents.

PMID: 3469455 [PubMed - indexed for MEDLINE]

194. J Toxicol Sci. 1987 Feb;12(1):11-21.

Effects of nivalenol on the bone marrow in mice.

Ryu JC, Ohtsubo K, Izumiyama N, Mori M, Tanaka T, Ueno Y.

In order to investigate the toxic effects of nivalenol, one of the trichothecene mycotoxins, we performed a short-term feeding trial for 24 days using feed supplemented with rice artificially molded with nivalenol producing fungus, Fusarium nivale Fn 2B, in female C57BL/6CrSlc SPF mice. A significant erythropenia and slight leukopenia were observed in the 30 ppm group, but no marked changes were observed in other hematological parameters, feed consumption, body weight gain, or weights of the liver, spleen, and thymus. Ultrastructural studies also revealed polyribosomal breakdowns of the bone marrow cells in the 30 ppm group.

PMID: 3599102 [PubMed - indexed for MEDLINE]

195. J Natl Cancer Inst. 1987 Feb;78(2):321-5.

Carcinogenicity of Fusarium moniliforme culture material in rats.

Jaskiewicz K, van Rensburg SJ, Marasas WF, Gelderblom WC.

Two isolates of Fusarium moniliforme from corn were used in a chronic study with groups of 30 inbred male BD IX rats fed a semipurified diet that was marginally adequate nutritionally. Group 1 served as the controls and received the semipurified diet containing 5% cornmeal, group 2 received 5% of strain MRC 1069 culture material that was nontoxic to rats, and group 3 received 0.5% of strain MRC 826 culture material that was highly toxic to rats. The amount of the mutagen fusarin C detected in the culture material of strains MRC 826 and MRC 1069 was 104 and 364 mg/kg, respectively. Survival up to 2 years was good in all groups. Pathologic examination showed that many rats in group 2 had mild ductular cell hyperplasia. Almost all rats in group 3 had neoplastic nodules, gamma-glutamyltransferase-positive foci, adenofibrosis, and esophageal basal cell hyperplasia. Whereas no tumors were induced in groups 1 and 2, the 21 long-term survivors in group 3 developed 8 cholangiocarcinomas, 2 hepatocellular carcinomas, 4 carcinomas of the forestomach epithelium, and 1 esophageal papilloma. Since neoplastic lesions were confined to rats in group 3 and the diet of these rats contained much less fusarin C than that of group 2, it is highly unlikely that fusarin C was responsible for the carcinogenicity of the MRC 826 culture material. It appears that the toxicity of F. moniliforme strains may be related to their carcinogenicity, but the chemical nature of the toxic and carcinogenic metabolite(s) produced by F. moniliforme MRC 826 remains unknown.

PMID: 3468296 [PubMed - indexed for MEDLINE]

196. Toxicol Pathol. 1987;15(3):308-19.

Experimental T-2 toxicosis in swine following inhalation exposure: effects on pulmonary and systemic immunity, and morphologic changes.

Pang VF, Lambert RJ, Felsburg PJ, Beasley VR, Buck WB, Haschek WM.

Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana 61801.

Thirty-four, 9- to 11-week-old, male castrated, crossbred, specific pathogen-free derived pigs were exposed to a T-2 toxin aerosol at a nebulized dose of 0 or 9 mg/kg in pairs, each pair consisting of 1 control and 1 T-2 treated pig which were exposed on the same day. Twenty to 30% of the toxin (1.8 to 2.7 mg/kg) was retained by the pigs. Five pairs were killed on each of 1, 3 and 7 days after dosing. Two pairs of pigs were designated as a 0.33-day group when one T-2 treated pig died and the other was killed in a moribund state at 8 to 10 hours after dosing. The pulmonary and systemic immunity and morphologic changes of the lungs and other organs were examined. Bronchoalveolar lavage was performed to obtain alveolar macrophages (AM) and pulmonary lymphocytes (PL). The phagocytic ability of AM and mitogen-induced blastogenic responses of enriched PL and peripheral blood lymphocytes were evaluated. Clinically, all of the T-2 treated pigs vomited and were cyanotic, anorexic, lethargic and laterally recumbent. In the 0.33-, 1-, and 3-day T-2 treated pigs, there was a marked reduction in AM phagocytosis and mitogen-induced blastogenic responses of PL but not of peripheral blood lymphocytes. Mild to moderate, multifocal interstitial pneumonia was seen in the majority of the T-2 treated pigs. In pigs dying following inhalation of T-2 toxin, there was a more severe pneumonia, as well as marked necrosis of lymphoid tissues, severe necrohemorrhagic gastroenteritis and edema of the gall bladder wall, and multifocal necrosis of the heart and pancreas. Thus, inhalation exposure to T-2 toxin can result in clinical signs and morphologic changes resembling those reported previously in pigs given T-2 toxin intravascularly (iv) at a dose of 1.2 mg/kg (approximate LD50) or greater, as well as death. Mild pulmonary injury as well as transient impairment of pulmonary immunity was present in pigs surviving inhalation exposure.

PMID: 3685791 [PubMed - indexed for MEDLINE]

197. Toxicon. 1987;25(2):167-74.

Cutaneous injury by topical T-2 toxin: involvement of microvessels and mast cells.

Yarom R, Bergmann F, Yagen B.

Topical applications of various doses of T-2 toxin to rats led to delayed skin reactions. Following a dose-dependent latent period of 12-24 hr, there appeared vascular dilation, stasis, edema and mononuclear cell infiltration, with many degranulating mast cells. These signs were earliest and strongest in the subcutis. Epidermal necrosis occurred 1-2 days later and was probably caused secondarily by ischemia, due to microcirculatory failure. Ultrastructurally, endothelial cells of small vessels were the earliest sites of change. While intercellular junctions remained closed and pinocytosis decreased, the cytoplasm contained many ribosomes, vacuoles, and abnormal mitochondria. Another early effect of topical T-2 toxin was an increase in number and degranulation of mast cells, especially in the subcutis. The resemblance of the skin injury to that produced by irradiation is noted.

PMID: 3576633 [PubMed - indexed for MEDLINE]

198. Food Addit Contam. 1987 Jan-Mar;4(1):49-56.

Protein synthesis inhibition and cardiac lesions associated with deoxynivalenol ingestion in mice.

Robbana-Barnat S, Loridon-Rosa B, Cohen H, Lafarge-Frayssinet C, Neish GA, Frayssinet C.

Deoxynivalenol (DON), an occasional contaminant of foodstuffs, has been implicated in outbreaks of mycotoxicosis. Balb-c mice that had ingested 0.35 mg/kg of DON showed a drastic decrease in food intake and concomitant loss of weight. Severe depletion of the lymphoid organs and liver were also observed. Cardiac lesions, appeared as calcified pericarditis foci in young animals fed a diet contaminated by 10 to 20 ppm of DON for a period of a few weeks. DON inhibited protein synthesis. This inhibition occurred at lower doses for the heart than for the other organs. This preferential effect on cardiac tissue correlated with the cardiotoxicity observed.

PMID: 3556676 [PubMed - indexed for MEDLINE]

199. Biull Eksp Biol Med. 1986 Oct;102(10):482-5.

[Hepatocyte ultrastructure in mice with chronic T-2 mycotoxicosis].

[Article in Russian]

Kravchenko LV, Khvylia SI, Levitskaia AB.

Trichothecene mycotoxin (T-2 toxin) was administered by gastric intubation to CBAXC57BL/6 mice at a dose of 0.33-0.45 mg/kg for 6 months. No symptoms of intoxication were observed, however, electron microscopic studies revealed a severe damage of hepatocyte structure, especially of smooth and rough endoplasmic reticulum. Besides the destruction of hepatocytes an increase in the number of primary and secondary lysosomes was observed. Regenerating foci were found in the majority of liver cells. In chronic T-2 mycotoxicosis there is a strong correlation between the damage of hepatocyte ultrastructure and the changes in organella-specific enzymatic activity in the liver, that was described previously.

PMID: 3768521 [PubMed - indexed for MEDLINE]

200. Toxicol Appl Pharmacol. 1986 Sep 15;85(2):207-14.

Scanning cytophotometric analysis of brain neuronal nuclear chromatin changes in acute T-2 toxin-treated rats.

Martin LJ, Doebler JA, Anthony A.

Male Sprague-Dawley rats (200 g) were injected intraperitoneally with T-2 toxin, a trichothecene mycotoxin protein synthesis inhibitor, at dosages of 0.75, 1.0, 1.5, and 6.0 mg/kg (1 LD50 = 0.9 mg/kg) before decapitation at 8-hr postexposure. Correlative data were obtained on changes in physicochemical properties of nuclear chromatin, chromatin dispersion, and nuclear volume of cerebrocortical (layer III) and striatal neurons using Feulgen-DNA (F-DNA) cytophotometry and ocular filar micrometry. Decreased lability of neurons to F-DNA acid hydrolysis (reduced F-DNA yield), nuclear shrinkage, and chromatin aggregation (decreased chromophore area) were used as indices of suppression of genomic template activity, i.e., neuronal nuclear functioning. Conversely, increased F-DNA yield, chromophore area, and nuclear volume signify enhanced neuronal activation. At 8 hr following T-2 toxin exposure, cerebrocortical and striatal neurons exhibited a dose-dependent decrease in F-DNA hydrolyzability, i.e., impaired chromatin activity, and increases in both chromatin dispersion and nuclear volume. Microscopic observation revealed no gross evidence of T-2 induced neurotoxicity. These data indicate that T-2 toxin elicits both neurochemical injury and adaptive or compensatory processes simultaneously. The toxicological importance of observed nuclear alterations and the role of impairments in central nervous system metabolism in acute T-2 toxicity remain to be ascertained.

PMID: 3764907 [PubMed - indexed for MEDLINE]

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