RÉSUMÉ
Objective To investigate the role of Hedgehog pathway in hepatic fibrosis and its association with activation of hepatic stellate cells. Methods Twenty male Spragur-Dawley rats were divided into control and model groups with 10 each. The animal models were induced by injection with CCl4 and fed with fat-rich diet. The rats in both groups were sacrified at the 8 week with 5 each and the liver tissues were removed for HSC-T6 culture. The deposition of collagen fiber in liver was detected with HE and Masson staining. RT-PCR was used to detect the expressions of Sonic hedgehog (Shh), smoothened (Smo), patched (Ptc), Gli-1 and α-smooth muscle action (α-SMA) mRNA in HSC-T6 and liver tissues. The influence of cyclopamine (Cyc) and lipopolysaccharide (LPS) on HSC-T6 proliferation were assayed by MTT. The expressions of Shh, Smo, Ptc, Gli-1 and α-SMA mRNA after intervention with Cyc (100μmol/L) and LPS were measured by real-time PCR. Results A lot of lipo and collagen deposited in liver of model rats. The Shh,Smo,Gli-1 and α-SMA mRNA were highly expressed in model rats than those in control group (2-△△Ct were 20.45±3.31 vs. 1, 12.78 ± 0. 53 vs. 1, 10.88 ± 2.41 vs. 1, 4.91 ± 2. 59 vs. 1, respectively, all P value <0. 05). In vitro Cyc inhibited HSC-T6 proliferation in dose dependant manner (F=636.81, P<0.01). Compared to the control group, the mRNA expressions of Smo, Ptc, Gli-1,α-SMA in HSC-T6 were significantly reduced after Cyc intervention (2△△Ct, were 0. 20±0. 11, 0. 21 ± 0. 08, 0. 28 ± 0. 05,0. 27±0.10,respectively, all P values<0.01). Conclusion The expression of members of Hedgehog pathway are increased in the progress of hepatic fibrosis, which may accelerate the hepatiee fibrosis by activating HSC.