Inhibitory mechanism of taurine against CCl4 induced hepatic fibrosis in rats

Effects of Ginkgo biloba extract on liver fibrosis induced by carbon tetrachloride in rats

AIM: To study the effects of Ginko biloba extract (EGb) on hepato-fibrosis induced by carbon tetrachloride (Cl₄) in rat model.

METHODS: Rat liver fibrosis model was induced by Cl₄ administration. Wistar rats were randomly divided into 5 groups: normal control group, a model group, a interven-tional group, a therapeutic group, and a EGb group. The EGb interventional group, apart from administration of Cl₄, was treated concurrently with EGb 0.3 g/kg, ig once a day; the EGb therapeutic group was treated with EGb 0.3 g/kg, ig once a day after cirrhosis was induced successfully, and the EGb group was treated only with EGb 0.3 g/kg, ig once a day. At the end of wk 8 and 16, all the rats were sacrificed. The pathological changes of liver were observed by H-E and Von-Gieson staining.The expression of mRNA and proteins of collagen I/TGF₁ in liver were determined by RT-PCR and immunohistochemistry.

RESULTS: The degree of liver fibrosis and level of mRNA and proteins of collagen I/TGF₁ in liver were significantly reduced in the EGb interventional and therapeutic groups compared with those in the model group (type I collagen mRNA: 0.0 778±0.054 vs 0.2 361±0.113, 0.1 075±0.007 vs 0.2 361±0.113, P < 0.01; type I collagen proteins: 0.2 563±0.0 009 vs 0.2 885±0.0 025, 0.2 541±0.0 076 vs 0.2 885±0.0 025 , P < 0.01; TGF₁ mRNA: 0.523±0.015 vs 0.956±0.049 , 0.524±0.009 vs 0.956±0.049, P < 0.01; TGF₁ proteins: 0.2 785±0.0 012 vs 0.3 015±0.0 012, 0.2 791±0.0 016 vs 0.3 015±0.0 012, P < 0.01).The EGb group had the same results as the normal control group.

CONCLUSION: EGb has prophylactic and therapeutic effects on CCl₄-induced rat liver fibrosis, probably through its anti-lipoperoxidation, suppressing the activation of hepatic stellate cells and transition and reducing the synthesis of hepatic type I collagen and TGF₁.