Aerobic Exercise and Granulocyte Colony-Stimulating Factor Treatment Augment Myocardial Regeneration in Rat with Myocardial Infarction

Objectives:To discuss the influence and possible mechanism of aerobic exercise(AE) and granulocyte colony-stimulating factor(G-CSF) treatment on myocardial regeneration and improvement of cardiac function in rats with myocardial infarction(MI).Methods:Adult male sprague-dawley rats,weight about 180²20g were randomly divided into:Sham-operated group(Sham),Sedentary MI group(MI),MI with AE group(ME),MI with G-CSF treatment group(MG) and MI with AE plus G-CSF treatment group(MGE).The MI model in rat was established by ligation of the left anterior descending(LAD) coronary artery,and rats in ME and MGE were subjected to 8-week treadmill training.At the end of the 8-week training,hemodynamic measurement was performed to evaluate cardiac function;hearts were picked for TTC dyeing and histological section;the expression levels of factors related to cell proliferation and stem cell homing were detected by immunohistochemical measurement,western blot or RT-PCR.Results:Compared to Sham,the MI rats were found to have impaired cardiac function and increased cardiac fibrosis,the expression levels of PCNA,Ki-67 and VLA-4 increased(P<0.01),and mRNA and protein levels of GATA4 decreased(P<0.01,P<0.05);compared to MI rats,AE or G-CSF treatment ameliorated cardiac remodeling,improved cardiac function,decreased infarct size(P<0.05),and increased the expression of PCNA,Ki-67,c-kit,CD29,CXCR4,VLA-4 in ME and MG rats;the combined treatment had a better effect than pure intervention factors.Conclusion:AE or G-CSF treatment significantly improved myocardial remodeling and cardiac function in MI rats,and increased myocardial cells regeneration and activation of the stem cell movement.The better effects were appeared with the combined treatment.