白藜芦醇对大鼠缺血再灌注心肌细胞凋亡的抑制作用与PI3K-Akt信号通路的关系

Inhibitory effect of resveratol on ischemia reperfusion-induced cardiocyte apoptosis and its relationship with PI3K-Akt signaling pathway

目的:探讨白藜芦醇对大鼠缺血再灌注心肌细胞凋亡的影响及与PI3K-Akt信号通路的关系。方法:50只成年雄性SD大鼠,随机分为5组,即对照组(SH组)、缺血再灌注组(I/R组)、白藜芦醇预处理组(Res组)、白藜芦醇预处理+渥曼青霉素组(Res+Wom组)、缺血再灌注+渥曼青霉素组(I/R+Wom组)。结扎冠状动脉左前降支制备心肌缺血模型,缺血45 min,再灌注120 min,测定再灌注心肌组织中NOS,NO的含量,并用末端脱氧核苷酸转移酶介导的带生物素的dUTP缺口末端标记(TUNEL)的方法测定细胞凋亡,免疫组化测定心肌组织中Bcl-2,Bax蛋白的表达,利用Western blot测定Akt(又称PKB,即蛋白激酶B)及p-Akt(即磷酸化蛋白激酶B)含量。结果:与I/R组及Res+Wom组比较,Res组NOS及NO表达增加,显著减轻心肌细胞凋亡,Bcl-2蛋白表达显著升高,Bax/Bcl-2降低,Akt的磷酸化水平增高,上述各项指标差异具有统计学意义(P<0.05),而上述变化能够被PI3K-Akt信号通路的特异性阻断剂渥曼青霉素所阻断,且其差异具有统计学意义(P<0.05)。结论:白藜芦醇能够抑制缺血再灌注所致的心肌细胞凋亡,此过程有PI3K-Akt信号通路的参与。

Objective： To study the effect of resveratol on ischemia reperfusion-induced cardiocyte apoptosis and its relationship with PI3K-Akt signaling pathway.Method： Fifty male SD rats were divided randomly into five groups： the control group（SH group）,the ischemia reperfusion group（I/R group）,the resveratol pretreatment group（Res group）,the resveratol pretreatment＋wortmannin group（Res＋Wom group） and the ischemia reperfusion＋wortmannin group（I/R＋Wom group）.The myocardial ischemia model was established by ligating left coronary artery for 45 min followed by 120 min reperfution,in order to observe the contents of NOS and NO.Cardiac myocyte apoptosis was determined by terminal deoxynueleotidyl transferase-mediated dUTP nick end labeling（TUNEL）.Bcl-2 and Bax proteins were detected by immunohistochemistry.The t-Akt and p-Akt signaling protein expressions were determined by Western blotting analysis.Result： Compared with the I/R groups and the Res＋Wom group,the Res group showed significant increase in the expressions of NOS,NO,Bcl-2 protein and p-Akt and notable decrease in cardiocyte apoptosis and Bax/Bcl-2.The difference of above indicators showed a statistical significance（P〈0.05）.Furthermore,above changes can be blocked by wortmannin,a specific blocker of PI3K-Akt signaling pathway,indicating a statistical significance in their changes（P〈0.05）.Conclusion： Resveratol can inhibit the ischemia reperfusion-induced cardiocyte apoptosis,in which PI3K-Akt signaling pathway gets involved.