Puerarin pretreatment inhibits myocardial apoptosis and improves cardiac function in rats after acute myocardial infarction through the PI3K/Akt signaling pathway

Background.Puerarin demonstrates a protective effect in many cardiovascular diseases.However, the role of puerarin in acute myocardial infarction (AMI)-induced injury and the exact molecular mechanisms are not fully understood.Objectives.To investigate whether puerarin pretreatment improves cardiac function and to study the mechanism of action of puerarin. Materials and methods.Thirty rats were grouped into sham group, AMI group and AMI+puerarin (PUE) group at random (n = 10 per group).Except for the sham group, a model of AMI was established via left anterior descending artery ligation.The PUE group received puerarin 120 mg/(kg × day) for 7 days before the operation.Echocardiography was used for evaluation of cardiac function in rats and TUNEL staining for measuring myocardial apoptosis.The expression levels of p-PI3K, t-Akt, p-Akt, Bax, Bcl-2, and cleaved caspase-3 proteins were measured with western blot.Results.Compared to the sham group, the AMI group demonstrated poor cardiac function and decreased p-PI3K, p-Akt and Bcl-2 proteins levels, while Bax, cleaved caspase-3, and myocardial apoptosis levels increased.Compared with the AMI group, the PUE group showed significant improvement in cardiac function and increased protein expression of p-PI3K, p-Akt and Bcl-2, while Bax and cleaved caspase-3 levels decreased and myocardial apoptosis was attenuated.Conclusions.Puerarin pretreatment in AMI can effectively improve cardiac function by inhibiting myocardial apoptosis.The molecular mechanism of this protective effect may be mediated by activating the PI3K/Akt pathway in cardiomyocytes.