Objective  To investigate the effect of walnut oligopeptides (WOPs) on acute alcohol-induced liver damage and the mechanism of the effect in rats.

  Methods  Seventy-two male Sprague-Dawley (SD) rats were randomly assigned into 6 groups: a normal, a model, and a whey protein group (220 mg/kg·bw) and 3 WOPs intervention groups (220, 440, 880 mg/kg·bw). Ethanol at the dose of 7 g/kg·bw was given intragastricly after WOPs treatment for 30 days. The content of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and the levels of reduced glutathione (GSH), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and malondialdehyde (MDA) in liver were measured using oxidative stress kit.

  Results  By the end of the intervention, the mental state and behavioral abnormalities of the WOPs group were better than those of the model control group. Compared with those of the model control group, the serum ALT level of the low, moderate and high WOPs groups (62.38 ± 9.36, 52.57 ± 9.11 and 64.17 ± 10.40 U/L) and AST contents (200.40 ± 50.87, 191.80 ± 76.12, 173.63 ± 41.35 U/L) were significantly lower (all P < 0.05); in liver tissues of the moderate and high WOPs groups, the SOD (149.21 ± 20.28, 153.45 ± 19.37 ng/L), GSH-PX (138.82 ± 9.93, 146.99 ± 15.05 IU/L) and GSH (568.15 ± 67.31, 571.61 ± 74.98 ng/L) were significantly increased (P < 0.05 for all) but the MDA, the lipid peroxidation metabolite induced by alcohol in liver tissues of the the low, moderat and high WOPs (3.83 ± 0.56, 3.62 ± 0.47, 3.94 ± 0.24 nmol/L) were decreased significantly (P < 0.05 for all).

  Conclusion  WOPs have protective effects on alcohol-induced acute liver injury in rats; the effects may be related to the inhibition of excessive oxidative stress and lipid peroxidation induced by alcohol and the improvement of antioxidant capacity.