RESUMO
This study is to investigate the therapeutic effect and mechanism of indole-3-carbinol (I3C) on pig serum-induced liver fibrosis of rats. The liver fibrotic model of rats was induced by pig serum. After models were successfully established, rats in the treatment groups were administered with I3C through intraperitoneal injection or curcumin by intragastric administration, daily for 17 days. Hepatic hydroxyproline (Hyp) content was measured. The liver histology and immunohistochemistry with a-smooth muscle actin (alpha-SMA) were assayed. Hepatic stellate cells line, HSC-T6 was incubated with different concentrations of I3C (25, 50, and 100 micromol x L(-1)) for 24 h. The effect of I3C on cell apoptosis was identified by FITC-Annexin V/PI double labeled assay. And the mRNA expressions of Bax and Bcl-2 were measured by real time RT-PCR. The results showed that hepatic content of Hyp decreased by I3C treatment, as compared with the fibrotic model control. Histopathological changes, such as steatosis, necrosis, deposition of collagenous fiber reduced remarkably and the expression of alpha-SMA was significantly down-regulated in the I3C-treated groups (P < 0.01). Apoptosis analysis showed that I3C significantly increased HSC-T6 apoptosis rate and the expressional ratio of Bax to Bcl-2. The results indicated that I3C could effectively cure pig serum-induced liver fibrosis in vivo by inducing HSC apoptosis and promoting ECM degradation.