Effect Of17-DMAG On Proliferation And Apoptosis Of Human Hepatic Satellite Cell Line LX2

Objective To investigate the anti-proliferative effect of Heat Shock Protein90(HSP90) inhibitor17-DMAG on the human hepatic satellite cell line LX2cells in vitro and explored the mechanism. Methods The LX2cells were cultured with or without17-DMAG (100,250,500or1000nmol/L) for24,48or72hour, then MTT assay was used to determine the anti-proliferation effect of17-DMAG on LX2cells. Inhibitory rate and IC50were calculated. For apoptosis assay, Annexin V-FITC/PI double-staining method with flow cytometry was used to assess the apoptosis rate of the treated cells after incubation for48or72hour. The expression level of α-SMA in the treated cells after48or72hour incubation was measured with western blotting. Results Our data demonstrated that17-DMAG could inhibit the proliferation of LX2cells in a time (24h、48h、72h) and dose (100-1000nmol/L) dependent manner (P<0.01). Higher dose of17-DMAG or longer exposure time resulted in significantly lower viability. The IC50after24,48and72hour exposure was757,380and121nmol/L, respectively. As determined with annexin V/PI double staining on flow cytometry,17-DMAG exposure on LX2cells for48or72hour significantly increased apoptotic rate relative to control group (46.68±2.46as to3.07±0.72after24hour exposure,62.84±2.73as to7.50±0.95after48hour exposure, respectively, P<0.01). Western blotting indicated significant decreased expression level of a-SMA in LX2cells exposed to17-DMAG for48or72hour compared to control group (P<0.05). Conclusions17-DMAG has anti-proliferation effect on LX2cells in a concentration (100-1000nmol/L) and time (24hour,48hour,72hour) dependent manners. The underlying mechanism involves increased apoptosis of LX2cells. Subsequently, the expression of a-SMA was decreased, suggesting therapeutic potential of17-DMAG against liver cirrhosis.