黄芪皂苷Ⅳ对大鼠脑缺血/再灌注损伤海马神经元凋亡及相关基因表达的影响

摘要

目的 探讨黄芪皂苷Ⅳ对大鼠缺血/再灌注损伤后海马神经元Bcl-2、Bax及神经元细胞凋亡表达的影响.方法 实验动物随机分为假手术组、模型组、黄芪皂苷Ⅳ组、尼莫地平对照组.线栓法建立大鼠大脑中动脉缺血(MCAO)模型,免疫组织化学方法检测大鼠海马Bcl-2、Bax蛋白表达,TUNEL方法检测神经元细胞凋亡.结果 与模型组和尼莫地平对照组比较,黄芪皂苷Ⅳ组Bax蛋白表达和细胞凋亡指数明显降低(P<0.05),Bcl-2蛋白表达及Bcl-2/Bax比值明显上调(P<0.05).结论 黄芪皂苷Ⅳ能够促进海马神经元Bcl-2表达,抑制Bax表达,升高Bcl-2/Bax比值,降低细胞凋亡指数,这可能是其抑制脑缺血后神经元凋亡的机制之一.%Objective To investigate the effect of Astragaloside Ⅳ on the apoptosis of neural cells and the expressions of Bcl-2 and Bax in hippocampus after cerebral ischemia-reperfusion in rats. Methods CIR injury was induced by middle cerebral artery occlusion( MCAO)in rats. 42 healthy SD rats were randomly divided into sham operation group, model group, nimodipine group and Astragaloside Ⅳ group. The expressions of Bcl-2 and Bax protein in hippocampus were observed using immunochemistry method. The apoptosis of neural cells was detected by TUNEL method. Results Compared with the model group and the Nimodipine group ,the apoptotic index and the expression of Bax protein were significantly lower in the Astragaloside Ⅳ group( P ＜ 0.05 ), but the expression of Bcl-2 protein and the ratio of Bcl-2 to Bax were significantly increased (P ＜0.05). Conclusion Astragaloside Ⅳ can restrain the apoptosis of neural cells in rats after cerebral ischemia-reperfusion, which may be related to the up-regulation of Bcl-2 expression and the ratio of Bcl-2 to Bax, and the down-regulation of Bax expression and the apoptotic index.