Aloperine Activates the PI3K/Akt Pathway and Protects Against Coronary Microembolisation-Induced Myocardial Injury in Rats

BACKGROUND: Coronary microembolisation (CME)-induced myocardial apoptosis is a key factor in progressive cardiac dysfunction. Aloperine (ALO) plays a protective role in the cardiovascular system, but its role and the mechanism -underlying its protection against CME are unclear. Therefore, we aimed to verify whether ALO has a protective effect against CME-induced myocardial injury, as well as whether this effect has a relationship with regulation of the PI3K/Akt pathway for rats. METHODS: Forty Sprague-Dawley rats were randomised into 4 equal groups: CME, CME + ALO, CME + ALO + LY294002 (LY) and a Sham group. Twelve hours after surgery, the rats' cardiac function, apoptosis index, microinfarct and serum cardiac-troponin I (cTnI) level were measured. Levels of p-Akt, total Akt, Bcl-2, Bax and cleaved caspase-3 were detected. RESULTS: ALO improved cardiac dysfunction induced by CME, while also decreasing serum levels of cTnI and microinfarct areas. In addition, ALO inhibited myocardial apoptosis, which may have been partially as a result of downregulated cleaved caspase-3 and Bax, upregulated Bcl-2 and increased protein levels in phosphorylated Akt. However, these ALO effects were blocked if ALO was administered along with LY. CONCLUSIONS: ALO can inhibit cardiomyocyte apoptosis and consequently attenuate CME-induced myocardial injury. These functions are realised by activating PI3K/Akt signalling pathway.