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Fumonisin B1, T-2 toxin, and deoxynivalenol are frequently detected in feed materials. The mycotoxins induce free radical formation and, thereby, lipid peroxidation. The effects of mycotoxin exposure at the EU recommended limit (T-2/HT-2 toxin: 0.25 mg/kg; DON = 3AcDON/15-AScDON: 5 mg/kg; fumonisin B1: 20 mg/kg) and double dose (T-2/HT-2 toxin: 0.5 mg/kg, DON/3-AcDON/15-AcDON: 10 mg, and FB1: 40 mg/kg feed) were investigated during short-term (3 days) per os exposure in the liver of laying hens. On day 1 higher while on day 3 lower MDA concentrations were found in the low-dose group compared to the control. Fatty acid composition also changed: the proportion of monounsaturated fatty acids increased (p < 0.05) and the proportion of polyunsaturated fatty acids decreased by day 3. These alterations resulted in a decrease in the index of unsaturation and average fatty acid chain length. Histopathological alterations suggested that the incidence and severity of liver lesions were higher in the mycotoxin-treated laying hens, and the symptoms correlated with the fatty acid profile of total phospholipids. Overall, the findings revealed that mycotoxin exposure, even at the EU-recommended limits, induced lipid peroxidation in the liver, which led to changes in fatty acid composition, matched with tissue damage. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to use oxidative stress markers for investigating the effect of zeolite (315 mg/kg of complete feed) in the case of aflatoxin B1 contamination (92 μg/kg complete feed). In a 21-day feeding trial with broiler chickens, oxidative stress parameters such as conjugated dienes, conjugated trienes, malondialdehyde, reduced glutathione content and glutathione peroxidase activity were not changed significantly by supplementation with this mycotoxin absorbent. The relative gene expression of transcription factors KEAP1 and NRF2 was not modified by the absorbent either. Still, the expression of GSS, GSR and GPX4 genes increased significantly due to the aluminosilicate supplementation. The results suggest that zeolite reduced lipid peroxidation in the blood plasma but not in the red blood cell haemolysate or the kidney. The relative expression of the genes encoding the glutathione redox system also changed as a result of zeolite supplementation, but these changes were not found at the protein level. [ABSTRACT FROM AUTHOR]

Short-term effects of T-2 toxin (1.13 mg/kg feed) was investigated in broiler chicken, in connection with dietary addition of a medicinal herbal mixture. Three-week old Cobb 540 broiler chickens (n=120) were randomly assigned into five experimental groups. In three experimental groups Herbamix® Basic Premix were used (300, 600 and 1500 mg/kg) as two weeks long pre-treatment. Samplings were done at every twelve hour. Parameters of lipid peroxidation and glutathione redox system were measured in blood plasma and red blood cell haemolysates. T-2 toxin treatment increased the GSH concentration and GPx activity of plasma at 12h and 24h, while most marked elevations were found in T-2 toxin+medium Herbamix dose group. The results revealed that T-2 toxin had pro-oxidant effect, and consequently activated the glutathione redox system of broiler chickens. The applied herbal mixture had only moderate effect against the mild oxidative stress caused by T-2 toxin at the dose applied. [ABSTRACT FROM AUTHOR]

The purpose of present study was to investigate the short-term effect of DON and T-2 toxin exposure on some blood and liver lipid peroxide and glutathione redox parameters in broiler chickens. A total of 120 three-week old Cobb 540 broiler chickens were randomly assigned into five experimental groups of 24 chickens in each. The short-term trial lasted for 48 hours, after 12 hours of feed deprivation. The experimentally mycotoxin-contaminated diets contained (1 kg) 3.74 mg T-2 or 16.12 mg DON, respectively. Herbal mixture (Herbamix Basic Premix™, Herbamix Trade Ltd., Budapest) was added to the complete feed at the dose of 600 mg/kg. Six birds of each group were slaughtered at 12th, 24th, 36th and 48th hours of the experiment. Parameters of the lipid peroxidation (malondialdehyde) and the glutathione redox system (reduced glutathione content and glutathione peroxidase activity) were measured in blood plasma and liver homogenate. Malondialdehyde content did not change in blood plasma but it was significantly lower in liver homogenate in both mycotoxin loaded groups fed with herbal mixture supplemented feed at 24 hour as compared to the control. Reduced glutathione content did not change significantly in blood plasma, but in liver homogenate, at 24 hour sampling, T-2 toxin alone or in combination with herbal mixture showed significantly higher values as compared to the control. In conclusion, the investigated trichothecene mycotoxins at the dose applied, activated the glutathione redox system in liver of broiler chicken, while addition of herbal mixture has moderate effect against the mild oxidative stress as caused by DON or T-2 toxin. [ABSTRACT FROM AUTHOR]

Authors studied the effect of sterigmatocystin from infected corn (STC), purified sterigmatocystin (PSTC), and aflatoxin B1 from infected corn (AFB1) on lipid peroxidation and glutathione redox parameters, including the expression of their encoding genes in a sub-chronic (14 days) trial. A total of 144 three-week-old cockerels was divided into four experimental groups (n = 36 in each). Control feed was contaminated with STC or PSTC (1590 µg STC/kg or 1570.5 µg STC/kg feed), or with AFB1 (149.1 µg AFB1/kg feed). Six birds from each group were sampled at day 1, 2, 3, 7 and 14 of mycotoxin exposure. As parameters of lipid peroxidation, conjugated dienes (CD) and trienes (CT) were measured in the liver, while malondialdehyde (MDA) concentration was determined in blood plasma, red blood cell hemolysate and liver. Reduced glutathione (GSH) concentration and glutathione peroxidase (GPx) activity were determined in the same samples, and expression of glutathione peroxidase 4 (GPX4), glutathione synthetase (GSS) and glutathione reductase (GSR) genes was measured by RT-PCR in the liver. STC, PSTC or AFB1 caused a slight, but not significant, increase in CD and CT levels; however, in the case of MDA, no increase was found in the liver. Glutathione redox system was activated in the liver by AFB1, but less markedly by STC/PSTC. PSTC and AFB1 resulted in a higher expression of GPX4, while GSS expression was down-regulated by AFB1 on day 1, but up-regulated by STC on day 2 and by both mycotoxins on day 7. However, on day 14, GSS expression was down-regulated by PSTC. Expression of GSR was low on day 1 in AFB1 and PSTC groups, but later it was up-regulated by AFB1. The observed changes regarding gene expression strengthen the hypothesis that the mild oxidative stress, caused by the applied STC doses, activates the glutathione redox system of broiler chickens. [ABSTRACT FROM AUTHOR]