Résumé
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.