Zhen Yuan Capsule Protects Myocardial Ischemia-reperfusion Injury By Regulating Autophagy Through PI3K/Akt/mTOR Signaling Pathway

In this study,the in vivo rat myocardial ischemia-reperfusion injury animal model was used to observe the protective effect of Zhenyuan capsule(ZYC)pretreatment on myocardial ischemia-reperfusion injury and its molecular mechanism.Research method: 150 Wistar rats were randomly divided into Sham group,MI/R group,ZYC(300,600 mg/kg)dose group and alprostadil group.By ligating the left anterior descending coronary artery of rats,ischemia 2 h,reperfusion 2 h to establish a model of myocardial ischemia-reperfusion injury in rats.Color Doppler ultrasound portable machine was used to detect rat heart function;determination of myocardial infarction area;application of biochemical kits to determine serum creatine kinase(CK-MB),Aspartate aminotransferase(AST)and LDH activity;spectrophotometric detection of SOD,GSH-Px,catalase(CAT)activity and MDA content in myocardial tissue;observation of H&E staining in myocardial tissue;detection by TUNEL method Apoptosis of myocardial tissue;Western Blot detection of apoptosis-related pathway protein expression in myocardial tissue,detection of expression and phosphorylation levels of LC3I/II、Atg5、Beclin1 and p62 proteins in autophagy-related pathway and PI3K/Akt/m TOR pathway of myocardial tissue.Research result: 1.ZYC 300 and 600 mg/kg can reduce LVIDd and LVIDs in MI/R rats,while increasing LVEF and LVFS,indicating that ZYC pretreatment can significantly improve the cardiac function of myocardial ischemia-reperfusion injury rats Compared with the MI/R group,ZYC 300 and 600 mg/kg can significantly reduce the myocardial infarction area in rats;ZYC reduce the pathological damage of MI/R rat myocardial tissue and reduce the CK-in rat serum MB,AST and LDH activities suggest that ZYC can protect myocardial ischemia-reperfusion injury.2.Compared with the MI/R group,ZYC 300 and 600 mg/kg can reduce the MDA content in myocardial tissue and increase the activities of SOD,CAT and GSH-Px,suggesting that ZYC exert myocardial protection by inhibiting oxidative stress response effect.3.Tunel staining results show that compared with the MI/R group,the ZYC 300,600 mg/kg group can significantly reduce the myocardial cell apoptosis index after myocardial ischemiareperfusion;Western Blot detection found that ZYC 300,600 mg/kg up-regulated Procaspase-3,Procaspase-9 and Bcl-2 protein expression levels,and down-regulated Bax protein expression levels,suggesting that ZYC can inhibit myocardial cell apoptosis induced by ischemia-reperfusion injury.4.Western Blot results show that ZYC pretreatment can significantly reduce the protein expression of Atg5,Beclin1 and LC3I/II in MI/R rat myocardial tissue,and upregulate the protein expression of p62,suggesting that ZYC is resistant to myocardial ischemia-reperfusion injury The effect is closely related to the inhibition of autophagy;ZYC can significantly increase the phosphorylation level of PI3 K,Akt and m TOR protein in the myocardial tissue of MI/R rats,suggesting that its activation of PI3K/Akt/m TOR signaling pathway play a important role in anti-myocardial ischemia-reperfusion injury effect.Research conclusion: This study confirmed that ZYC pretreatment has a protective effect on myocardial ischemia-reperfusion injury in rats,and its mechanism of action was initially described.ZYC pretreatment inhibits autologous activity by activating PI3K/Akt/m TOR signaling pathway.