Abstract: Objective:To investigate the lipid-lowering effect and antioxidant activity of polysaccharide from Schisandra Chinensis (SCP) in the rats with non-alcoholic fatty liver disease (NAFLD) induced by high-fat diet, and to provide a theoretical basis for the development and utilization of Schisandra Chinensis. Methods:A total of 32 male Wistar rats were selected. Sixteen from the 32 rats were randomly selected and divided into normal control group (intragastrical administration of water, combined with normal diet, n=8) and SCP group (intragastrical administration of 50 mg·kg^-1SCP, combined with normal diet, n=8). The remaining 16 rats were fed with high-fat diet for 4 weeks and the confirmed NAFLD rat models were set up. A total of 16 NAFLD rats were randomly divided into NAFLD group (intragastrical administration of water, combined with high-fat diet, n=8) and NAFLD+SCP group (intragastrical administration of 50 mg·kg^-1SCP, combined with high-fat diet, n=8). After treated for 12 weeks, the body weights of all the rats were weighed and the liver index was calculated. The levels of total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the serum of all the rats were determined. The levels of TC and TG in liver tissue of the rats were measured by enzymatic method.The malondialdehyde (MDA) levels and superoxide dismutase (SOD) activities in serum and liver tissue and the glutathione(GSH) levels in liver tissue of the rats were analyzed by TBA, xanthinoxidase and microscale enzyme methods, respectively. HE staining was used to observe the pathomorphology of liver tissue of the rats. Results:Compared with normal control group, the liver index of the rats in NAFLD group was increased (P < 0.01); the levels of TC, TG, LDL-C, ALT and AST in serum of the rats were increased(P < 0.01), the levels of TC and TG in liver tissue of the rats were increased (P < 0.01), the MDA level was increased(P < 0.01) and the SOD activity was decreased(P < 0.01), and the GSH levels in liver tissue and serum were decreased(P < 0.01). Compared with NAFLD group, the body weight and liver index, serum levels of TC, TG, LDL-C, ALT and AST of the rats in NAFLD+SCP group were decreased (P < 0.05), the levels of TC and TG in liver tissue were decreased(P < 0.01), the MDA level was decreased (P < 0.01),the SOD activities in serum and liver tissue were increased(P < 0.01), and the level of GSH in liver tissue was increased(P < 0.01). The HE staining results showed that the structure of hepatic lobules of the rats in NAFLD group was disordered and showed significant hepatic steatosis,and the hepatic steatosis in hepatic lobules of the rats in NAFLD+SCP group was significantly reduced. Conclusion:SCP has a regulation effect in the NAFLD rats induced by high-fat diet, and its mechanism may be related to the anti-oxidative stress.

Key words: Schisandra Chinensis, polysaccharide, oxidative stress, non-alcoholic fatty liver disease