人参皂苷Rg1对抗多巴胺对PC12细胞凋亡的诱导作用

Protective effect of ginsenoside Rg1 on PC12 cells against apoptosis induced by dopamine

通过测定细胞的凋亡率 ,内源性NO的水平和iNOSmRNA的表达及半胱天冬酶 3的活性 ,探讨人参皂苷Rg1对抗多巴胺对PC12细胞凋亡诱导作用的可能机理 .结果表明多巴胺 (0 .15～ 0 .60mmol·L- 1)可诱导PC12细胞凋亡 ,预先经过 10 μmol·L- 1Rg 1处理后 ,PC12细胞的凋亡率显著下降 (P <0 .0 0 1) ,同时NO2- 水平和iNOSmRNA表达水平及半胱天冬酶 3活力较单纯多巴胺处理组明显降低(P <0 .0 0 1) .结果提示 ,Rg1减少细胞内源性NO的生成及抑制半胱天冬酶 3的活化可能是Rg1对抗多巴胺诱导PC12细胞凋亡的重要机理 .

To explore the possible mechanism of the protective effect of ginsenoside Rg1 on PC12 cells against apoptosis induced by dopamine(DA), the ratio of apoptotic cells, endogenous nitric oxide, iNOS mRNA and caspase-3 activity were measured, respectively. The results showed: ①DA induced PC12 cells apoptosis at concentrations from 0.15 to 0.60 mmol·L -1; ②compared with application of DA alone, the ratio of apopto- tic cells decreased significantly after pretreatment with Rg1 at the concentration of 10 μmol·L -1, so did the levels of nitrite and caspase-3 activity(P<0.001); ③the expression of iNOS mRNA decreased after pretreatment with Rg1 (P<0.001). The results suggest that ginsenoside Rg1 protect against dopamine-induced apoptosis in PC12 cells and this effect be attributed to its reducing the formation of endogenous NO and its inhibitory action on the activation of caspase-3.