Genetic Variants Affecting Lipid and Glucose Metabolism in Obese Pediatric Population

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Preliminary investigations into the effect of feeding mannan oligosaccharide(MOS) on the genotoxic effect of T-2 toxin in rabbits measured by comet assay

T-2 toxin is a secondary fungal metabolite produced by Fusarium species. Several in vitro and in vivo studies described genotoxic potential of T-2 toxin, which is generally accepted to be caused by oxidative stress. There are some data showing that colonic probiotic bacteria can remove mycotoxins via physical binding. Mannan oligosaccharides (MOS) are widely used animal feed to improve gastrointestinal health. Because of their interaction with microbes, the aim of our study was to determine the possible protective effect of MOS in T-2 toxicosis. Sucking rabbits were randomly assigned into two experimental groups, the control (C, n = 20) and the prebiotic (P, n = 20) group. In group P the feed of the does was completed with MOS. The young rabbits were allowed to consume the feed of the does from about the 17th days of age. The rabbits were weaned on the 35th day. At 7 weeks of age both groups (C and P) were divided into two (n = 10 in each), and half of the C and P rabbits were fed with the same diet as before, but contaminated with 2 mg/kg feed T-2 toxin (groups CT and PT). The animals were fed the toxin containing diet for the duration of 21 days. At the end of the 10th week blood samples were collected from 6 animals from group C, CT and PT. Mononuclear cells obtained from the rabbits were tested in comet assay to detect the genotoxic effect of T-2. All control samples (C) were negative in the test, i.e. all cells were scored as ‘0’. T-2 toxin in 2 mg/kg feed concentration had genotoxic effect on the rabbits’ lymphocytes, as could be concluded from the comet values. MOS supplementation in the feed had significant protective effect against T-2 as seen by the lower comet score frequencies compared to T-2 treated animals. These results demonstrate that MOS may reduce risk associated with the uptake of mycotoxins probably by their binding capacity or antioxidative properties

Preliminary investigations on the single and combined cytotoxic effect of T-2 and HT-2 measured by Methyl Thiazol Tetrazolium (MTT) cytotoxicity test using pig lymphocytes

Fusariotoxins are frequently existing contaminants in cereal and other plant products. High relationship was found between the levels of the trichothecene T-2 and HT-2 toxin detected in contaminated commodities. Many in vitro studies investigated the cytotoxicity of T-2 and HT-2, but the interaction between them has not been thoroughly studied yet. The aim of the study was to examine the dose dependent cytotoxic effect of T-2 and HT-2 toxins, single and in combination, using pig lymphocytes in the methyl thiazol tetrazolium (MTT ) assay. The mycotoxins were added at various concentrations, i.e. 0.5, 0.1, 0.05, 0.01 and 0.001 μM of T-2; 1.0, 0.5, 0.2., 0.1 and 0.05 μM of HT-2; and both mycotoxins combined. Two exposure times (6 and 24 h) were tested. Both T-2 and HT-2 toxins exerted a dose dependent effect. After 6 h incubation, the increase in concentration of T-2 from 0.001 to 0.5 μM and HT-2 for 0.05 to 1.0 μM resulted in lower cell viability by 22 and 17%, respectively. After 24 h cell viability was significantly lower compared to values obtained at 6 h, except 0.5 μM T-2 and 0.05, 1.0 μM HT-2, respectively. Measured cell viability for combinations of T-2 and HT-2 was higher compared to the calculated expected values. The two toxins caused lower cell survival when applied together than in single administration after 6 h incubation. After 24 h incubation this tendency was not consistent

DOSE-RELATED GENOTOXIC EFFECT OF T-2 TOXIN MEASURED BY COMET ASSAY USING PERIPHERAL BLOOD MONONUCLEAR CELLS OF HEALTHY PIGS

T-2 toxin is the most acutely toxic trichothecene mycotoxin: it inhibits protein, DNA and RNA synthesis. The main goal of this study was to evaluate the rate of DNA damage caused by T-2 toxin in porcine mononuclear cells in increasing concentrations (0.1, 0.5 and 1.0 μmol) and after two different incubation periods (24 and 42 h). The lowest concentration caused DNA damage and about 50% of the treated cells could be categorised as having 1 to 4 scores in comet assay. In parallel with the increase of T-2 toxin concentration, the frequency of intact lymphocytes decreased from 50.2% (0.1 μM) to 36.3% (1.0 μM) in the first 24 h. In case of score 3, the highest concentration of T-2 toxin resulted in a 5-fold change, as compared to the lowest dose. Cells with score 4 were found only after exposure to 1.0 μM T-2 toxin. The exposure time did not have a significant effect on the results, while concentration did (P < 0.0001). However, a significant interaction between concentration and time as fixed factors (P < 0.0001) was found. When these were combined as a single factor, the results showed a significant toxin treatment effect on the results. It was concluded that a time- and dose-dependent DNA damaging effect of T-2 toxin could be demonstrated using peripheral blood mononuclear cells from healthy pigs by comet assay

Preliminary results on the interactive effects of deoxynivalenol, zearalenone and fumonisin B1 on porcine lymphocytes

Fusarium mycotoxins, such as fumonisin B1 (FB1), deoxynivalenol (DON) and zearalenone (ZEN), frequently co-occur in feed raw materials and their presence is ubiquitous. The aims of this study were to determine the concentration that inhibits cell viability by 50% (IC50 values) for each mycotoxin (after 24, 48 and 72 h) and to investigate their combined effects in binary (DON + ZEN: DZ, DON + FB1: DF, FB1 + ZEN: FZ) and ternary (DFZ) mixtures using cyto- and genotoxicity on porcine lymphocytes as endpoints. The potency of cytotoxicity of the three toxins in an increasing order was FB1 1 (50% viability was reached only after 72 h). The main interaction observed was antagonism regarding cytotoxicity. Lower and higher sets of concentrations were used for the genotoxicity (comet assay) experiments. When lower concentrations were used, antagonism was again the main interaction observed. However, at higher concentrations an antagonism was confirmed only for DFZ, whereas for DZ and FZ a synergism was observed. Interactions of DF were inconsistent in different exposure periods in both series of experiments. Further studies with additional endpoints should be performed (e.g. DNA fragmentation, protein synthesis) in order to elucidate the mechanisms underlying the interactions observed

No association of the cytotoxic T-lymphocyte associated gene CTLA4 +49A/G polymorphisms with Crohn’s disease and ulcerative colitis in Hungarian population samples

AIM: The goal of the current work was to analyse the prevalence of the +49A/G variant of the cytotoxic T-lymphocyte antigen 4 gene (CTLA4) in Hungarian patients with Crohnos disease (CD) and ulcerative colitis (UC). METHODS: A total of 130 unrelated subjects with CD and 150 with UC, and 170 matched controls were genotyped for the single nucleotide polymorphism (SNP). The genotypes were determined by using PCR/RFLP test. RESULTS: The G allele frequency and the prevalence of the GG genotype were 38.1% and 12.3% in the CD group, 40.6% and 18.6% in the UC patients, and 37.4% and 15.9% in the control group, respectively. CONCLUSION: The results of the current study show that carriage of the +49G SNP in heterozygous or in homozygous form does not confer risk either for CD or for UC in the Hungarian population

Individual and combined effects of feed artificially contaminated with with fumonisin B 1 and T-2 toxin in weaned rabbits

Co-contamination of feed and feed raw materials with two or more mycotoxins is frequently reported, however, only a few studies have investigated the combined effects of low doses of multiple mycotoxins. In the present study the individual and combined effects of 10 mg/kg fumonisin B1 and 2 mg/kg T-2 toxin (n=12/group) were investigated in weaned rabbits. Mycotoxin contaminated feed was produced by adding fungal cultures of Fusarium verticillioides and Fusarium sporotrichioides, and fed to 40 days old rabbits during 28 days. Feed intake and body weight were measured weekly, serum biochemistry and antioxidant parameters on day 0, 14 and 28, while histopathological examination and comet assay were performed at the end of the experiment. T-2 exposure both alone and in combination resulted in 15-18% less final body weight compared to the control and FB1 treatment. There was a significant increase in the concentration of plasma total protein, albumin, fructosamine and creatinine in the group treated with FB1 compared to the control. The liver and the kidney of most animals treated with T-2 toxin, FB1 and their combination showed pathological changes, occurring more frequent in animals exposed to both toxins. T-2 resulted in depletion of lymphocytes in the spleen. FB1 and T-2 exerted synergistic effect on the antioxidant/oxidative parameters after 2 weeks of exposure, manifesting in less glutathione and glutathione peroxidase, while more malondialdehyde was produced. Both toxins caused DNA damage in the lymphocytes, which was more pronounced in the group fed T-2 toxin and T-2 combined with FB1, without additive or synergistic effects