异源脱细胞基质心肌补片改善大鼠心肌梗死后心功能OA

Objective To explore the therapeutic effect and underlying mechanism of a porcine-derived decellularized extracellular matrix(dECM)patch in rats with myocardial infarction(MI).Methods Porcine cardiac dECM patches were prepared using a physico-chemical combined method.SD rats were randomly divided into sham group,MI group,and MI+dECM group.Four weeks after surgery,cardiac function was assessed by echocardiography,including left ventricular ejection fraction(LVEF),left ventricular fractional shortening(LVFS),and left ventricular internal dimension at end-systole(LVIDs).Pathological changes of myocardial tissue were observed by hematoxylin-eosin and Masson staining.The in vivo immune response was evaluated by immunofluorescence staining and the expres-sion of key proteins in the PI3K/Akt pathway was detected by Western blot.Results The rat models of myocardial infarction and dECM patch transplantation were successfully established.Compared with sham group,MI group had significantly decreased LVEF and LVFS(P<0.05),remarkably increased LVIDs(P<0.05),aggravated myocardial fibrosis,significantly increased myocardial infarct size(P<0.05),and notably down-regulated expression of p-PI3K and p-Akt proteins(P<0.05).Compared with MI group,LVEF and LVFS significantly increased while LVIDs significantly reduced in MI+dECM group(all P<0.05);the myocardial fibrosis was allevi-ated and myocardial infarct size reduced in MI+dECM group(P<0.05);no obvious immune cell infiltration was observed in MI+dECM group;moreover,the expression levels of p-PI3K and p-Akt were significantly up-regulated(P<0.05).Conclusion The xenogeneic dECM patch may improve cardiac function and reduce myocardial fibrosis after myocardial infarction by activating the PI3K/Akt signaling pathway.And it does not cause obvious immune rejection,showing good tissue compatibility.These findings suggest that the xenogeneic dECM patch is a promising myocardial repair material for clinical application.