Keywords: 
• Schisandra chinensis /
• astragalus polysaccharides /
• paracetamol /
• liver injury

Abstract: Objective : To study the synergistic protective effect and mechanism of extracts from Fructus Schisandrae chinensis(EFS) with astragalus polysaccharides(APS) on paracetamol-induced liver injury in mice. Methods :Mice liver injury was induced by peritoneal injection paracetamol physiologic saline solution at a dose of 500 mg/kg.The activities of serum alanine aminotransferase(ALT) and asparate aminotransferase(AST),the contents of malondialdehyde(MDA) and glutathione(GSH) in the liver tissue,and the liver histopathological changes were observed to evaluate the effects of EFS,APS and their combination on liver injury. Results : The EFS(270 mg/kg) or APS(900 mg/kg) alone did not produce any effect on liver injury induced by paracetamol in mice.The combination of EFS at dose of 30、90 and 270 mg/kg respectively with APS at dose of 100、300 and 900 mg/kg significantly decreased the activities of ALT and AST in serum and MAD level in liver tissue(P<0.05 or P<0.01),increased the GSH content in liver tissue(P<0.05 or P<0.01),and improved liver histopathological changes.The coefficients drug interaction(CDI) of related parameters between EFS(270 mg/kg) and APS(900 mg/kg) were all less than 0.7. Conclusion :The combination of EFS and APS reduced the ALT and AST level in serum,improved the liver histopathological changes of liver injury mice through synergistically increasing GSH content and antioxidant ability of liver.