Protective effect of erythropoietin derived peptide on heart in rats with acute myocardial infarction

Objective To investigate the protective effect of helix B surface peptide (HBSP) on the heart of rats with acute myocardial infarction (AMI). Methods Thirty 8-week-old male SD rats were randomly divided into 3 groups: sham operation group (sham group), AMI group and HBSP group. The AMI rat model was established by ligating the anterior descending coronary artery. The treatment group was intraperitoneally injected with HBSP (90 μg/kg), the sham operation group and AMI group were intraperitoneally injected with the same amount of normal saline. Cardiac function was detected by color Doppler echocardiography 24 hours after operation. The myocardial signal transduction and transcription activator 3 (STAT3), B lymphocytoma 2 gene (Bcl-2) were detected by Western blotting in each group of rats. Apoptosis was detected by expression of Bcl-2, Bax protein (BCL2 associated X protein) and detection of myocardial fineness by in situ Nick end labeling (TUNEL). Results Compared with AMI group, myocardial infarction size and cardiac function of rats in HBSP group were significantly improved. STAT3, Bcl-2 expression in AMI group was significantly lower than that in sham operation group (P<0.01). In HBSP group, STAT3 was significantly higher than that in sham operation group (P<0.01). In HBSP group, the expression of Bcl-2 was significantly higher than that of AMI, while the expression of Bax was significantly decreased (P<0.01). Compared with the sham operation group, the cardiomyocyte apoptosis rate in the AMI group was significantly increased, while that in the HBSP group was significantly lower than that in the sham operation group (P<0.01). AMI model group was significantly lower than that in the sham operation group. The cardiac function in HBSP group was significantly higher than that in AMI model group (P<0.01). Conclusion HBSP can increase the expression of STAT3, Bcl-2 and inhibit the apoptosis of myocardial cells in rats with acute myocardial infarction, thereby protecting myocardial tissue and improving cardiac function in rats.