ABSTRACT
ObjectiveTo investigate the effect of NGF on apoptosis of HSC in vitro and explore the possible mechanism.MethodsHSC was incubated with different concentrations of NGF.HSC apoptosis was identified by FCM.The expressions of apoptosis-regulating proteins Caspase-3,p53 and Bcl-2 of HSC after apoptosis induced by NGF were examined by immunohistochemical staining.Expressions of NGF and p75NTR were detected by immunofluorescence.ResultsApoptosis index of HSC was higher than that of control group [(22.36±9.51)％ vs (5.88±1.36)％] after treated with NGF (100 ng/ml) (P＜0.05).After incubating with 100 ng/ml NGF for 24 h,the positive expression rates of p53 and Caspase-3 of HSC increased significantly than those of control group [(78.41±4.00)％ vs (34.96±3.84)％,(39.26±1.57)％ vs (9.27±1.01)％,P ＜0.05].The positive expression rate of Bcl-2 protein of HSC significantly decreased compared with that of control group (18.12±1.38)％ vs (91.53±2.98)％ (P＜0.05).When HSC was stimulated with 100 ng/ml NGF for 24 h,the average optical density of NGF increased significantly than control group (6.53±1.40 vs 1.77±0.17) (P＜0.05),while the expression of p75NTR was not significantly changed (3.52±0.36 vs 4.24±0.38) (P＞0.05).ConclusionsThe mechanism of NGF to induce HSC apoptosis may be associated with the up-regulating expression of Caspase3,P53 and down-regulating expression of Bcl-2 on HSC.NGF could be used as an initiating factor and effect factor to increase the expression of NGF on HSC,but it had no significant effect on p75NTR expression.
ABSTRACT
Objective To explore the different concentrations of glycyrrhizin on hepatic stellate cell proliferation and its regulation mechanism.MethodsHepatic stellate cell proliferation rate of three different concentrations of glycyrrhizin was detected by MTT assay.The expression of cyclin E was detected by immunocytochemistry.ResultsMTT assay was used to detect the cell proliferation inhabitation in different concentration groups,from control group 0.8 mg/L glycyrrhizin group to 1.2 mg/L glycyrrhizin group and 1.6 mg/L glycyrrhizin group.The cell proliferation inhibited rates were 0,2.73%,14.75 % and 25.96%.The difference was significant (P＜0.05).The numbers of Cyclin E positive cells in different concentrations of glycyrrhizin group were significantly different compared with control group,and it was concentration dependently decreased (P＜0.01).ConclusionsGlycyrrhizin concentration dependently inhibited rat hepatic stellate cells proliferation and it could reduce the expression of cyclin E and inhibit the proliferation of rat hepatic stellate cells.