人参皂苷Rg1可能通过丝裂素活化蛋白激酶途径抑制细胞凋亡人参皂苷Rg1可能通过丝裂素活化蛋白激酶途径抑制细胞凋亡

目的探讨人参皂苷Rg1对MPP⁺诱导细胞凋亡保护作用的可能信号传导途径。方法用吖啶橙-溴化乙锭染色观察SHSY5Y细胞凋亡率,流式细胞仪检测细胞内活性氧ROS水平,Western Blotting法检测JNK(c-jun NH₂-terminal kinase)激酶活性,免疫细胞化学染色法检测裂解的Caspase-3阳性细胞的表达率。结果经10 μmol·L^-1 Rg1或2.5 mmol·L^-1 N-乙酰半胱氨酸预处理后,MPP⁺诱导的SHSY5Y细胞凋亡受到明显抑制,同时细胞内ROS下降,JNK激酶的活性减弱,裂解的Caspase-3阳性细胞表达率下降。结论Rg1可抑制MPP⁺诱导的SHSY5Y细胞凋亡,其作用机制可能是通过清除ROS、减弱JNK激酶的活性,从而减少Caspase-3的激活

Ginsenoside Rg1 may protect SHSY5Y cells from apoptosis induced by MPP+ through JNK way

AIM: To explore possible signal transmission way through which ginsenoside Rg1 protect cells from MPP(+)-induced apoptosis. METHODS: The apoptosis of SHSY5Y induced by 1-methyl-4-phenylpyridinium (MPP+) was observed by AO-EB staining. Flow cytometry was used to quantitate the reactive oxygen species (ROS). Western Blotting was used to detect the c-jun NH2-terminal kinase (JNK) activity in SHSY5Y cells. Immunocytochemistry staining was used to detect cleaved Caspase-3 positive cells. RESULTS: MPP+ was shown to induce apoptosis in SHSY5Y cells. The percentage of apoptotic SHSY5Y cells induced by MPP+ was obviously lower in those groups pretreated with 10 mumol.L-1 Rg1 or 2.5 mmol.L-1 N-acetylcysyteine (NAC). It showed more ROS in MPP+ groups than in control. JNK activity increased with time within 72 hours in 1 mmol.L-1 MPP+ group. Simultaneously, it showed decrease of ROS, less activity of JNK and lower expression of cleaved Caspase-3 in 10 mumol.L-1 Rg1 and 2.5 mmol.L-1 NAC pretreated groups compared with groups treated with MPP+ only. CONCLUSION: Rg1 protects against MPP(+)-induced apoptosis in SHSY5Y cells and the effect might be attributed to its removal of ROS, inhibition of the activity of JNK and expression of cleaved Caspase-3.