关键词: CCl4, 壳寡糖, 肝保护 , 抗氧化

Abstract: The protective effects of chitosan oligosaccharide (COS), D-glucosamine (GlcNH2) and N-acetyl-D-glucosamine (GlcNAc) on carbon tetrachloride (CCl4) induced hepatotoxicity in male ICR mice were investigated and the possible mechanisms involved were discussed . CCl4(20mg/kg body weight) administration induces marked increase in serum AST and ALT activities, primes liver lipid peroxidation, depletes sulfhydryl content, impairs total antioxidant capabilities (T-AOC) and induces genotoxicity 24h after administration. Pretreatment with COS, GlcNH2, and GlcNAc (1.5g/kg body weight) for 12 consecutive days prior to CCl4 challenge significantly induces metallothionein (MT) expression. Thus, the antioxidant defensive system in the body is strengthened to counteract the oxidative damage induced by the CCl4 administration. Serum AST and ALT activities are effectively decreased. Hepatic malondialdehyde (MDA) formation is inhibited, and sulfhydryl contents and T-AOC are markedly restored. Genotoxicity as reflected by DNA fragmentation, however, it is not mitigated by pretreatment with COS, GlcNH2, and GlcNAc. The results suggest that pretreatment with COS, GlcNH2, and GlcNAc can efficiently protect mice against CCl4-induced toxicity, of which GlcNH2 is the most effective.

Key words: hepatoprotective activity , antioxidant activity, chitosan oligosaccharide, carbon tetrachloride