Abstract: Objective: To investigate the protective effects of Ginkgo biloba extract(GBE) on paracetamol(APAP)-induced acute hepatic injury in mice and its mechanism. Methods: Thirty mice were randomly divided into control group, model group, GBE low, medium and high-dose(50,100,and 200 mg·kg^-1)groups,with 6 mice in each group. All mice except control group were administered with APAP(300 mg/kg)for one time by intraperitoneal injection. The mice in GBE low, medium and high-dose groups were intragastric administered with GBE for 2 d consecutively, then samples were harvested for analysis. The appearance and pathology of liver were observed. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in serum and the levels of superoxide dismutase (SOD), myeloperoxidase(MPO), glutathione (GSH) and malondialdehyde (MDA) in hepatic tissue were measured. Western blot was used to detect the protein expressions of Nrf2 and HO-1. Results: Compared with control group, in model group, the appearance and pathology of liver were bad, the levels of ALT,AST,TNF-α and IL-6 in serum were increased significantly(P<0.01),the levels of GSH and SOD were decreased while the levels of MDA and MPO were increased in hepatic tissue(P<0.01), the expressions of Nrf2 and HO-1 were increased in hepatic tissue(P<0.05). Compared with model group, in GBE groups, the appearance and pathology of liver were improved, the levels of ALT,AST,TNF-α and IL-6 in serum were decreased significantly(P<0.01), the levels of GSH and SOD were increased while the levels of MDA and MPO were decreased in hepatic tissue(P<0.01), the expression of Nrf2 and HO-1 were increased in hepatic tissue(P<0.05). The high-dose of GBE possessed the most obvious treatment effect among them. Conclusion: GBE may play a protective role in APAP-induced acute hepatic injury through Nrf2/HO-1 pathway.

Key words: Ginkgo biloba extract, paracetamol, oxidative stress, mice, acute hepatic injury