Methionine hydroxy analogue prevents oxidative damage and improves antioxidant status of intestine and hepatopancreas for juvenile Jian carp (Cyprinus carpio var. Jian)

Oxidative damage and antioxidant status of intestine and hepatopancreas for juvenile Jian carp (Cyprinus carpio var. Jian) fed graded levels of methionine hydroxy analogue (MHA: 0, 5.1, 7.6, 10.2, 12.7, 15.3 g kg(-1) diet) for 60 days were studied. Radical scavenging ability, antioxidant enzymes activities such as superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), glutathione peroxidase (GPX) and glutathione reducase (GR), as well as glutathione (GSH), protein carbonyl (PC) and malondialdehyde (MDA) contents were assayed in these tissues. Results indicated that anti-superoxide anion capacity in intestine and anti-hydroxyl radical capacity in hepatopancreas significantly improved with dietary MHA levels up to 7.6 and 10.2 g kg(-1) diet respectively, whereupon they decreased (P < 0.05). SOD, CAT, GST, GPX, GR activities in intestine and hepatopancreas, as well as GSH content in hepatopancreas significantly increased with optimal MHA levels which were in the range of 5.1-10.2 g kg(-1) diet, and thereafter decreased (P < 0.05). Meanwhile, MDA and PC contents in these tissues together with GOT and GPT activities in plasma significantly decreased with optimal MHA levels which were in the range of 5.1-7.6 g kg(-1) diet, and thereafter increased (P < 0.05). These results suggested that MHA improved antioxidant status and depressed lipid and protein oxidation in intestine and hepatopancreas.