Vitamin C protects piglet liver against zearalenone-induced oxidative stress by modulating expression of nuclear receptors PXR and CAR and their target genes

Zearalenone (ZEN), one of the most common mycotoxins found in human food and animal feed, has been shown to be effectively detoxified by vitamin C (Vc). The aim of this study was to investigate how vitamin C protects the piglet liver against oxidative stress induced by ZEN. A total of thirty-two healthy female crossbred weaning piglets (Duroc x Landrace x Large white) with an initial weight of 12.27 +/- 0.30 kg were randomly divided into four treatment groups of eight piglets per group. The dietary treatments included two zearalenone levels (0 mg kg(-1) and 1.0 mg kg(-1)) and two vitamin C levels (2 mg kg-1 and 150 mg kg(-1)) in a 2 x 2 factorial arrangement, and the trial period was twenty-eight days. The results showed that dietary zearalenone could significantly increase the liver coefficient (P < 0.05) and ZEN residues in the liver of weaning piglets (P < 0.05), and hepatocyte swelling and granular degeneration were obvious. Additionally, dietary zearalenone significantly increased the level of MDA (P < 0.05) and decreased the level of SOD, T-AOC and GSHPx in the liver of piglets (P < 0.05). However, the addition of 150 mg kg-1 vitamin C to dietary zearalenone decreased the effects of zearalenone on the liver coefficient, ZEN residues and oxidative stress, which decreased the level of MDA and increased the levels of SOD, T-AOC and GSHPx in the liver of piglets. Overall, there was a significant increase in the mRNA levels of nuclear receptor genes (PXR, CAR), phase I metabolic enzyme genes (CYP1A1, CYP1A2, CYP1A6) and phase II metabolic enzyme genes (UGT1A1, UGT1A3, UGT1A6). In conclusion, vitamin C can alleviate damage to the liver of weaning piglets by modulating the nuclear receptor signaling pathway.