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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. lhwanganna@126.com
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. saura.sahu@fda.hhs.gov
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.
m.casteel@mh.vetmed.uni-muenchen.de
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. Ahmed.Osman@rivm.nl
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. bb_yaoyunfeng@126.com
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. elena.pieckova@szu.sk
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.
breda.jakovac-strajn@vf.uni-lj.si
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. m.kolf-clauw@envt.fr
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. lukasz.zielonka@uwm.edu.pl
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.
c.nielsen@mh.vetmed.uni-muenchen.de
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.
kazimierz.obremski@uwm.edu.pl
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.
sven.daenicke@fli.bund.de
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. lorella.severino@unina.it
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. stefano.costa6@unibo.it
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. tiemann@fbn-dummerstorf.de
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. saura.sahu@fda.hhs.gov
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. moon@pusan.ac.kr
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. audre@lzi.lt
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. ixy@case.edu
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. tiemann@fbn-dummerstorf.de
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.
elena.pieckova@szu.sk
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.
s.bony@vet-lyon.fr
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.
tiemann@fbn-dummerstorf.de
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. tcollins@cfsan.fda.gov
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. sehata@sankyo.co.jp
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. rsprando@cfsan.fda.gov
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. ixy@po.cwru.edu
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. susanne.doell@fal.de
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. mikami@affrc.go.jp
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.
sehata@sankyo.co.jp
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. hsia@cber.fda.gov
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.
asehata@mail.ecc.u-tokyo.ac.jp
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, Italy.fiorena.minervini@ispa.cnr.it
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. fvetamp@hotmail.com
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. jorn.holme@fhi.no
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.
doccroft@hotmail.com
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. pestka@pilot.msu.edu
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. a80518@mail.ecc.u-tokyo.ac.jp
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. a_stellamaris@yahoo.com
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. aa77/45@mail.ecc.u-tokyo.ac.jp
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. hartL@pilot.msu.edu
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. aa57133@hongo.ecc.u-tokyo.ac.jp
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. miurakaz@niah.affrc.go.jp
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. rihe@slv.se
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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