三七总皂苷对脑缺血再灌注后神经元凋亡及凋亡线粒体途径和c-Jun氨基末端激酶表达的影响

Effect of Panax Notoginseng Saponins on Neuronal Apoptosis and Mitochondrial Apoptosis Pathway Expression c-Jun N-terminal Kinase after Cerebral Ischemia-reperfusion in Mice

目的:研究三七总皂苷对小鼠脑缺血再灌注后神经元凋亡及凋亡的线粒体途径相关蛋白细胞色素C(CytC),半胱氨酰天冬氨酸蛋白酶-9(caspase-9),caspase-3和磷酸化c-Jun氨基末端激酶(p-JNK1/2)表达的影响,探讨其抗脑缺血后神经元凋亡的机制。方法:C57BL/6小鼠随机分成假手术组、模型组、三七总皂苷组及依达拉奉组,连续给药4 d后结扎双侧颈总动脉造成脑缺血20 min,再灌注24,48 h,用Tunel法检测神经元凋亡,Western-blot法检测脑组织caspase-9,caspase-3,CytC和p-JNK1/2蛋白的表达。结果:脑缺血再灌注后24,48 h,模型组神经元凋亡率增加,脑组织CytC,caspase-9,caspase-3,p-JNK1/2蛋白表达均显著增强,与假手术组比较,差异具有统计学意义(P<0.01)。三七总皂苷组神经元凋亡率显著下降,脑组织CytC,caspase-9,caspase-3,p-JNK1/2蛋白表达均显著降低,与模型组比较,差异均具有统计学意义(P<0.05或P<0.01)。结论:三七总皂苷可抑制脑缺血再灌注后神经元凋亡,其机制可能与其抑制JNK信号转导蛋白激活、抑制线粒体凋亡途径有关。

Objective：To investigate the effect of Panax Notoginseng Saponins（PNS）on neuronal apoptosis and mitochondrial apoptosis pathway and c-Jun N-terminal kinase（JNK） activation after cerebral ischemia-reperfusion injury in mice.Method：C57BL /6 mice were randomly divided into sham-operation group,model group,PNS group and edaravone group.Cerebral ischemia-reperfusion injury was prepared by bilateral common carotid artery ligation for 20 min followed by reperfusion for 24 h and 48 h after drug administration for 4 days.Neuronal apoptosis was determined with Tunel and the expression of p-JNK1 /2,cysteine-asparate protease-9（caspase-9）,caspase-3 and cytochrome C（CytC） protein in brain tissue was detected with Western-blot.Result：After cerebral ischemia for 20 min followed reperfusion for 24 and 48 h,the neuronal apoptosis rate was enhanced significantly（P 〈 0.01）,the expression of p-JNK1 /2,CytC,caspase-9 and caspase-3 protein in brain tissue was increased（P 〈0.01）.The neuronal apoptosis rate in the PNS group was significantly lower than that of the model group（P 〈 0.01）,the expression of p-JNK1 /2,CytC,caspase-9 and caspase-3 protein in PNS group was lower than that of the model group significantly（P 〈 0.01 or P 〈 0.05）.Conclusion： PNS could attenuate neuronal apoptosis rate by inhibiting activation of signal transduction of JNK and mitochondrial apoptosis pathway after cerebral ischemia / reperfusion injury in mice.