Neuroprotective effects of ginsenoside Rg1 on 1-methyl-4-phenylpyridinum-induced apoptosis in PC12 cells

Abstract

Objective To explore the neuroprotective effect of ginsenoside Rg1 against PC12 cell apoptosis induced by 1-methyl-4-phenylpyridinum(MPP+).Methods MPP+-induced apoptosis in PC12 cells,with the characteristics of dopaminergic neuron,were taken as the model of Parkinson disease in vitro.The cells were divided into control group,MPP+ group and 3 ginsenoside Rg1 pretreatment groups(concentrations 10,20,and 50 μmol/L).MTT assay was used for detecting the cell viability,FCM for apoptosis ratio,TUNEL enzyme labelling for DNA fragment of the cell nuclear,and Western blotting analysis for cytochrome C protein.Results Ginsenoside Rg1(10,20,and 50 μmol/L) showed protective effect against MPP+-induced PC12 cells injury.Compared with MPP+-treated cells([52±4.7]%),pretreatment with 10,20,and 50 μmol/L ginsenoside Rg1 increased the cell viability to(64±3.4)%,(72±5.2)% and(83±6.2)%,respectively(P0.05 or P0.01).FCM analysis indicated that apoptosis rates decreased by ginsenoside Rg1 pretreatment,with the apoptosis rates in the control,MPP+ and 3 ginsenoside Rg1 groups(10,20,50 μmol/L) being 1.8%,44.5%,32.9%,21.1% and 14.2%,respectively.We also found that ginsenoside Rg1 pretreatment greatly decreased DNA fragment of PC12 cells.Western blotting analysis indicated that the cytochrome C was depressed by the ginsenoside Rg1 pretreatment.Conclusion Ginsenoside Rg1 can protect PC12 cells against MPP+-induced apoptosis in a concentration-dependent manner,which may be closely related to down-regulation of cytochrome C over-expression in the mitochondria.