葛根素对实验性缺血性脑血管病保护作用的细胞分子机理研究

目的探讨葛根素对大鼠缺血性脑细胞损伤的保护作用,以HSP70蛋白、Fas蛋白表达水平、神经细胞死亡情况等指标阐明其作用机制.方法采用闭夹大脑中动脉制作局部特定区域急性脑缺血大鼠模型,闭夹和重新开放大脑中动脉引起再灌注损伤制作缺血再灌注损伤模型,并在损伤前给予葛根素进行干预.对实验标本作HE染色,及用免疫组化SP法测定HSP70和Fas表达情况,光镜观察脑组织损伤程度.结果①在急性脑缺血期,葛根素干预组的HSP70蛋白表达明显强于单纯缺血组(P＜0.01),两组间Fas表达比较则无统计学意义(P＞0.05);葛根素干预组的神经细胞死亡率明显少于单纯缺血组,葛根素干预暴露因素与神经细胞死亡呈显著负相关(P＜0.01).②在脑缺血再灌注期,葛根素保护组的HSP70蛋白表达明显强于非保护组(P＜0.01),而Fas蛋白表达明显弱于非保护组(P＜0.01),葛根素保护组的神经细胞死亡率明显少于非保护组,葛根素干预暴露因素与神经细胞死亡呈显著负相关(P＜0.01).结论葛根素对急性脑缺血及缺血再灌注所致的脑细胞损伤均有保护作用,对急性缺血性损伤的保护作用可能主要通过上调HSP70蛋白的表达而实现的,而与Fas蛋白的表达相关不强;对脑缺血再灌注损伤的保护作用除上调HSP70表达外,还可能与下调Fas蛋白的表达、减少细胞凋亡有关.

The Molecular Mechanism of Puerarin on the Protection of Cerebral Ischemia injury in rat

Objective To study the protection of puerarin and its effect on the expressions of HSP_ 70 and Fas as well as its protected molecular mechanism in rat's cerebral ischemia injury.Methods Rat models of acute local cerebral ischemia and cerebral ischemia-reperfusion were made by ligated middle cerebral artery.The puerarin was injected into the rat's belly before ligating the cerebral artery.The histopathological damage was assessed and the expressions of HSP_ 70 and Fas protein were detected by histochemistry in SP method.Results In the acute cerebral ischemia injury groups,The number of death neurons were significantly less and the expression of HSP_ 70 was strongly higher in puerarin treated group than that of without using puerarin(P<0.01).While there was no significant difference in Fas expression in both groups(P>0.05).There was negative association between the number of death cells and puerarin interference(P<0.01).In the cerebral ischemia-reperfusion groups,the number of death neurons were significantly less and the expression of HSP_(70) was strongly higher,while the Fas expression was weaker in the puerarin treated group than that of without using puerarin(P<0.01).There was negative association between the number of death cells and puerarin interference(P<0.01).Conclusion Puerarin can prevent the neuron damage after acute cerebral ischemia and reperfusion injury in rats.It can up-regulate the expression of HSP_ 70 to protect the neurons during acute cerebral ischemia.While during the cerebral ischemia-reperfusion injury,it is not only up-regulated the expression of HSP_(70) but down-regulated the expression of Fas to reduce the neuronal apoptosis as well in order to protect the cerebral tissue.