Abstract: The purpose was to explore the protective effect and mechanism of the extract fraction of the Hypericum japonicum Thunb (HJT) on hepatic fibrosis induced by carbon tetrachloride (CCl₄) in rats.60 male rats were randomly divided into normal group,model group,colchicine (0.12 mg/kg) group and HJT (16 000,8 000,4 000 mg/kg,crude drug dose) groups,with 10 rats in each group.Except for the normal group,other rats were intraperitoneal injection of 40% CCl₄ olive oil mixed solution (1 mL/kg) twice a week for 6 weeks.From the first day of modeling,each administration group was administered by gavage with the corresponding drugs for intervention.Normal group and model group were given the same volume of distilled water once a day.After the last administration,the eyeballs was removed for taking blood and liver tissues were collected.The pathological changes of liver were observed by hematoxylin-eosin staining (HE) and Masson staining.The serum levels of alanine aminotransferase (ALT),aspartate aminotransferase (AST),hyaluronic acid (HA),laminin (LN),procollagetype Ⅲ (PCⅢ) and collage type Ⅳ (Ⅳ-C) were detected by biochemical detection.The levels of superoxide dismutase (SOD),glutathione glutathione peroxidase (GSH-PX),malonaldehyde (MDA),interleukin-1β (IL-1β),interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay (ELISA).Western blot was used to detect the protein expression of transforming growth factor-β1 (TGF-β1) and α-smooth muscle actin (α-SMA).The results showed that HJT (16 000,8 000,4 000 mg/kg) and colchicine could significantly reduce the activities or contents of ALT,AST,PC-Ⅲ,Ⅳ-C,reduce the level of MDA in liver tissue,increase the activities of SOD and GSH-PX,and reduce the secretions of IL-1β,IL-6 and TNF-α.The results of histological sections showed that the degree of inflammatory necrosis and hepatic fibrosis in liver of each HJT dose group and colchicine group were significantly reduced.The results of the study show that HJT has a significant protective effect on CCl₄-induced hepatic fibrosis,and its mechanism may be related to anti-inflammation,anti-oxidation and inhibition of TGF-β1 protein expression.

Key words: Hypericum japonicum Thunb, hepatic fibrosis, carbon tetrachloride, anti-inflammator, antioxidant, TGF-β1