Exposure to a Combination of Fusarium Mycotoxins Leads to Lipid Peroxidation and Influences Antioxidant Defenses, Fatty Acid Composition of Phospholipids, and Renal Histology in Laying Hens

Abstract

The effects of combined short-term (3 days) exposure to Fusarium mycotoxins at both the EU recommended limit (T-2/HT-2 toxin: 0.25 mg/kg; DON/3-AcDON/15-AcDON: 5 mg/kg; FB₁: 20 mg/kg) and twice the dose (T-2/HT-2 toxin: 0.5 mg/kg, DON/3-AcDON/15-AcDON: 10 mg/kg, and FB₁: 40 mg/kg feed) on the kidneys of laying hens were examined. Our study aimed to investigate how these mycotoxins interacted with membrane lipid fatty acid (FA) composition and lipid peroxidation processes. It was observed that the levels of conjugated dienes and trienes were higher than the control in the low-mix group on day 3, and malondialdehyde concentration was higher on days 2 and 3. The proportion of phospholipid (PL) FAs showed that saturated and monounsaturated FAs increased. Still, both n3 and n6 polyunsaturated FAs decreased significantly on day 2 of exposure in the high-mix group. Among the n3 FAs, the level of docosahexaenoic (C22:6 n3) and among n6 FAs, arachidonic (C20:4 n6) acids decreased mainly on day 2 in the high-mix group. The results suggest that the combined exposure to Fusarium mycotoxins induced lipid peroxidation in the kidneys of laying hens, which resulted in marked changes in the PL FA profile. Histological examination revealed time- and dose-dependent increases as consequences of mycotoxin exposure.

Keywords: T-2 toxin; deoxynivalenol; fumonisin B1; glutathione redox system; laying hens; lipid composition; lipid peroxidation; oxidative stress.

Figure A1

Results of histological examination: (A) marked focal mononuclear cell infiltration in the interstitium (H-E; 400X); (B) mild mononuclear cell infiltration in the interstitium surrounded with normal tubuli (H-E; 400X); (C) multifocal tubular damage with marked cellular detachment (H-E; 400X); (D) marked tubular lesions in the kidney with cellular detachment (black arrow), hydropic degeneration (white arrow), and karyopyknosis (arrowhead). Detached cells and cellular debris can be seen in multiple tubuli (asterisk)—H-E; 600X.

Figure 1

The oxidative (“(A)” CD, “(B)” CT, “(C)” MDA) parameters in the kidneys of laying hens (mean ± S.D.; n = 6). * p  <  0.05; ** p  <  0.01; *** p  <  0.001; **** p  <  0.0001. Low-mix group: T-2/HT-2 toxin: 0.25 mg/kg; DON/3-AcDON/15-AcDON: 5 mg/kg; FB₁: 20 mg/kg, High-mix group: T-2/HT-2 toxin: 0.5 mg/kg, DON/3-AcDON/15-AcDON: 10 mg; FB₁:40 mg/kg feed.

Figure 2

Changes in the unsaturation index dependent on exposure time and mycotoxin dose (A) and the mean length of fatty acid chains (B); ** p  <  0.01; **** p  <  0.0001. Low-mix group: T-2/HT-2 toxin: 0.25 mg/kg; DON/3-AcDON/15-AcDON: 5 mg/kg; FB₁: 20 mg/kg feed, high-mix group: T-2/HT-2 toxin: 0.5 mg/kg, DON/3-AcDON/15-AcDON: 10 mg; FB₁:40 mg/kg feed.