Protective Effects of Soybean Isoflavone on Myocardial Ischemia-Reperfusion Injury in Rats

Objective:To explore the protective effect of soybean isoflavone on myocardial ischemia-reperfusion injury in rats and its possible mechanism.Methods:Coronary artery ligation was adopted to establish myocardial ischemia-reperfusion model in rats.A total of 100 male SD rats were randomly divided into four groups(n=25)according to random number table,including sham operation(Sham)group,ischemia-reperfusion(I/R)group,soybean isoflavone(SI)treatment group,and SI+JAK kinase inhibitor AG490(SI+AG490)group.The apoptosis of myocardial cells was detected by TdT-mediated dUTP nick end labeling(TUNEL)assay;the expression levels of apoptosis-related factors including Bax and Bcl-2 were detected by immunohistochemistry;the expression levels of Janus activated kinase 2(JAK2),phosphorylated JAK2 and signal transducer and activator of transcription3(STAT3)proteins were detected by Western blotting.Results:Compared with I/R group,the apoptotic index(AI)was significantly decreased in SI group,the expression of Bcl-2 protein was significantly increased,the expression of Bax protein was significantly decreased,and the phosphorylated JAK2 and STAT3 proteins were significantly increased.There were significant differences(P0.01).Compared with SI group,AI was significantly increased in SI+AG490 group,the expression of Bcl-2 protein was significantly decreased,and the expression of Bax protein was significantly increased,the phosphorylated JAK2 and STAT3 proteins were significantly decreased.There were significant differences(P0.01).Conclusions:Soybean isoflavone intervention before myocardial ischemia-reperfusion can significantly reduce ischemia-reperfusion-induced myocardial apoptosis,and the protective mechanism may be related to the JAK-STAT signaling pathway.