JAK2/STAT3信号通路在人参皂苷Re预处理预防异丙肾上腺素致急性心肌缺血损伤中的作用

摘要

目的 观察人参皂苷Re预处理对异丙肾上腺素致急性心肌缺血大鼠心肌JAK2/STAT3通路的影响.方法 应用异丙肾上腺素建立SD大鼠急性心肌缺血模型,将75只大鼠随机分为空白对照组(Control)、模型组(Model)、葛根素对照组(PUE)、Re高剂量组(Re-H,20 mg·kg-1)、Re低剂量组(Re-L,10 mg·kg-1).Moor激光血流成像系统观测各组大鼠心脏表面血流值;ELISA法测定各组大鼠心肌中CK、LDH、SOD、MDA、GSH的含量;免疫组化法检测Bax、Bcl-2蛋白表达;Western blot方法检测各组大鼠心肌JAK、p-JAK、STAT3、p-STAT3蛋白的表达变化.结果 与对照组比较,模型组大鼠心脏表面平均血流量明显下降,心肌CK、LDH、MDA含量升高,GSH、SOD含量下降,Bcl-2/Bax比值下降(P<0.05),JAK2/STAT3通路蛋白的表达有所增加;与模型组比较,Re-H组心肌表面平均血流有明显提升(P<0.05);CK、LDH、MDA含量降低,GSH-Px含量升高(P<0.05),Bcl-2/Bax比值上升(P<0.05),JAK2/STAT3通路蛋白的表达明显增强(P<0.05).结论 人参皂苷Re预处理对急性心肌缺血大鼠心肌有较好的保护作用,该作用可能与JAK2/STAT3通路的激活有关.%Aim To observe the protective effect of ginsenoside Re pretreatment on rats with isoproterenol-induced acute myocardial ischemia via JAK 2/STAT3 signaling pathway .Methods SD rat model with acute myocardial ischemia was established using isoprotere-nol.Seventy-five rats were randomly divided into five groups: control group, model group , puerarin group (PUE), high dose group (Re-H, 20 mg· kg -1) and Re low-dose group ( Re-L, 10 mg kg -1 ) .The blood flow on the heart surface of rats in each group was ob-served by moor laser blood flow imaging system .The levels of CK , LDH, SOD, MDA and GSH in myocar-dium were measured by ELISA .The expressions of Bax and Bcl-2 proteins were detected by immunohistochem-istry.The expressions of JAK , p-JAK, STAT3 and p-STAT3 proteins were detected by Western blot .Re-sults Compared with the control group , the mean blood flow on the heart surface of rats in the model group significantly decreased , the levels of CK , LDH and MDA in the myocardium increased , the levels of GSH and SOD decreased , the ratio of Bcl-2/Bax de-creased ( P <0.05 ) , and the expression of JAK 2/STAT3 pathway related proteins was enhanced ( P <0.05 ) . The mean blood flow on the heart surface markedly increased , the levels of CK , LDH and MDA decreased , the level of GSH-Px increased , the ratio of Bcl-2/Bax increased, and the expression of JAK2/STAT3 pathway proteins evidently increased in the Re-H group compared with those of the model group ( P<0.05 ) .Conclusion Ginsenoside Re pretreatment has a good protective effect on the myocardium in rats with acute myocardial ischemia , which may be related to the activation of JAK2/STAT3 signaling pathway .