Effects of Yigan Decoction on proliferation and apoptosis of hepatic stellate cells

AIM: To investigate the effects of Chinese herb Yigan Decoction on proliferation and apoptosis of the hepatic stellate cells (HSC) in vitro. METHODS: The study in vitro was carried out in the culture of HSC lines. Various concentrations of Yigan Decoction were added and incubated. Cell proliferation was detected with MTT colorimetric assay. Cell apoptosis was detected by electron microscopy, flow cytometry and TUNEL. RESULTS: The proliferation of HSC was inhibited by Yigan Decoction, which depending on dose and time significantly. The HSC proliferation rates of groups at the end concentrations 144 and 72 (g.L-1) were 21.62 % and 40.54 % respectively, significantly lower than that of normal control group( P < 0.01). The HSC proliferation rates of groups at the end concentrations 36, 18 and 9 (g.L-1) were 54.05 %, 45.95 % and 51.35 % respectively, lower than that of control group( P < 0.05). When the end concentration was 4.5 g.L-1, the proliferation rate was 83.78 %, which appeared no significant differences compared with control group. At the same concentrations of 18 g.L-1, the inhibitory effects of Yigan Decoction at 24 h, 48 h and 72 h time point were observed, the effects were time-dependent, and reached a peak at 72 h. Meanwhile, it was showed that the inducing effects of Yigan Decoction on HSC apoptosis were dose-dependent and time-dependent, The apoptosis index(Al) was detected by TUNEL. After Yigan Decoction had been incubated for 48 h at the end concentration of 18 g.L-1, the Al(14.5 +/- 3.1) % was significantly higher than that of control group (4.3 +/- 1.3) % (P < 0.01). When visualized under transmission electron microscopy, some apoptotic stellate cells were found, i. e. dilated endoplasmic reticulum, irregular nuclei, chromatin condensation and heterochromatin ranked along inside of nuclear membrane. By flow cytometry detection, after HSC was treated with Yigan Decoction at different concentrations of 36, 18 and 9(g .L-1) for 48 h, Al(%) were 13.3 +/- 3.2, 10.7 +/- 2.7 and 10.1 +/- 2.5 respectively, which were significantly higher than that of control group (4.1 +/- 1.9) (P < 0.01). At the same concentration of 18 g.L-1 for 24 h, 48 h and 72 h, Al (%) were 9.3 +/- 1.8, 10.7 +/- 2.7 and 14.6 +/- 4.3 respectively, which were significantly higher than that of control group (P < 0. 01). CONCLUSION: Yigan Decoction could significantly inhibit HSC proliferation and increase the apoptosis index of HSC dose-dependently and time-dependently, which may be related to its mechanism of antifibrosis.