Protective effect of Schisandra polysaccharide on acute liver injury induced by CCl_4 in mice and its mechanism

Objective To explore the protective effect of Schisandra polysaccharide(SCP)on acute chemical liver injury induced by carbon tetrachloride(CCl4)in mice and to reveal its mechanism.Methods 50 mice were randomly divided into normal control group,model group,low dose of SCP group(SCP,50mg·kg-1),high dose of SCP group(SCP,100mg·kg-1)and positive control group(bifendate,150mg·kg-1).All the mice were intragastrically administrated the corresponding agents respectively for 15d.1hafter the last administration, 10% CCl4(2.0mL·kg-1)was given to mice in all groups except control group in a single intraperitoneal injection to establish the acute liver injury mouse models.6hlater,the mice were sacrificed,and the liver index,alanine aminotransferase(ALT)and aspartate aminotransferase(AST)activities,total bilirubin(TBIL)level in serumwere detected,and the malondialdehyde(MDA)and glutathione(GSH)levels,and nitric oxide synthase(NOS) activity in liver tissue were tested.HE staining was performed for observing the pathological changes of the liver tissue.Results Compared with normal control group,the liver quality,liver index,ALT,AST levels and TBIL level in serum,the MDA level and NOS activity in liver tissue in model group were all increased significantly(P0.01),and the GSH level in liver tissue was decreased(P0.01).Compared with model group,the liver quality and liver index of the mice in high dose of SCP group were decreased(P0.05);the ALT and AST activities in serum,and the MDA level in liver tissue in low dose of SCP,high dose of SCP and positive control groups were decreased significantly(P0.05or P0.01),while the GSH levels in liver tissue were increased(P0.05);both the serum TBIL level and NOS activity in liver tissue in high dose of SCP group were reduced(P0.05or P0.01).Moreover,the HE staining results showed that the size of liver cells was increased and the cytoplasm was stained lightly,and eosinophilic degeneration could be also seen in some individual liver cells in model group.The morphological damage of liver cells and the eosinophilic degeneration were significantly improved in SCP group.Conclusion SCP has a significantly protective effect on CCl4-induced acute liver injury,which might be related to the anti-oxidation.