Preliminary Research On The Mechanism Of Apoptosis Of Hepatic Stellate Cells Induced By Curcumin

Objective1. To investigate the effect of curcumin on proliferation and apoptosis of hepatic stellate cell (HSC) in vitro.2. To explore the mechanism of curcumin in inducing apoptosis of HSC by studying the expressions of apoptosis-regulating proteins Fas, p53 and bcl-2 on HSC.MethodsHSC cell lines T6(HSC-T6) was incubated with different concentrations of curcumin. The effect of curcumin on cell proliferation was observed by XTT colormetric assay. HSC-T6 apoptosis was identified by flow cytometry (FCM) and agarose gel electrophoresis. And then the expression of apoptosis-regulating protein Fas, p53 and Bcl-2 on HSC-T6 after apoptosis induced by curcumin were examined by immunohistochemical staining assay(SABC).ResultsAdministration of 20~160μmol/L curcumin incubated with curcumin for 12h, 24h, 36h and 48h could significantly inhibit HSC proliferation in dose-dependent manner compared with the control group (p<0.05) . After treating HSC-T6 with curcumin at concentration of 20, 30, 40μmol/L for 24h, apoptosis index (%) of HSC-T6 were (11.6 ± 2.79) %, (25.2 ± 4.38) %, (87.1 ± 12.6)% respectively, which were significantly higher than that of control group (3.8±0.64) % ( P<0.05) . An oligonucleosomal DNA ladder of curcumin-treated cells was demonstrated. Incubated HSC-T6 with curcumin 20 ±mol/L for 24h , the positive expression rates ofapoptosis-regulating protein Fas, p53 and Bcl-2 were significantly difference from that of control group: (87.4 + 2.8) % vs (33.1 + 3.1) %, (43.10 + 7.3) % vs (20.6 + 7.2) % ,(28.7 + 6.06)% vs (95.4 + 3.6) % respectively (p<0.05).Conclusions1. Curcumin could significantly inhibit HSC proliferation and induce apoptosis.2. Expressions of Fas and p53 on apoptotic HSC were increased while expression of bcl-2 was reduced.3. The mechanism of Curcumin to induce HSC apoptosis may be associted with the up-regulating expressions of Fas, p53 and down-regulating expressions of bcl-2 on HSC.