靶向磷酸二酯酶5的短发夹RNA导入后的间充质干细胞对心肌梗死后心室重构的影响

目的 探讨磷酸二酯酶5(PDE5)短发夹RNA(shRNA)重组腺病毒载体PDE5shRNA]导入后的间充质干细胞(MSCs)对心肌梗死(MI)后心室重构的影响.方法 构建PDE5shRNA转染的MSCs,结扎大鼠冠状动脉左前降支(LAD)建立MI模型,随机分成假手术组(n =4,只穿线不结扎LAD);模型组(n =...

Effects of MSCs with shRNA targeting phosphodiesterase 5 on ventricular remodeling after myocardial infarction

Objective To investigate the effects of mesenchymal stem cells(MSCs)with short hairpin RNA(shRNA)targeting phosphodiesterase 5(PDE5)on ventricular remodeling after myocardial infarction(MI).Methods MI model rats were established by ligating left anterior descending coronary artery(LAD),and MSCs were constructed by transfecting with PDE5 shRNA.The rats were randomly divided into sham operation group(n=4,only threading without ligating LAD),the model group(n=4,threading and ligating LAD),MSCs-Ad-Null group(n=4,injected with MSCs transfected with blank adenovirus vector based on MI model)and MSCs-shRNA-PDE5 group(n=4,injected with MSCs transfected with PDE5shRNA based on MI model).After modeling,one rat heart from each group was taken for pathological examination to judge the success of modeling.The relevant indicators were observed in other rats.After 4 weeks,cardiac function indexes were measured by echocardiography,including left ventricular end-systolic diameter(LVESd),left ventricular end-distolic diameter(LVEDd),left ventricular ejection fraction(LVEF)and percent fractional shortening(FS)of left ventricular short axis;myocardial pathological changes were observed by HE staining;myocardial fibrosis was observed by Masson staining;the relative expression level of PDE5,cyclic guanosine monophosphate(cGMP)and protein kinase G(PKG)mRNA were detected by real-time quantitative polymerase chain reaction(qRT-PCR).Results After 4 weeks,echocardiography showed the obviously dilated ventricle cavity and decreased myocardial systolic function of left ventricle in MI rats.Compared with sham operation group,LVESd and LVEDd increased,and LVEF and FS decreased in other three groups(all P<0.05).Compared with model group,LVESd and LVEDd decreased in MSCs-Ad-Null group and MSCs-shRNA-PDE5 group,and LVEF and FS increased in MSCs-shRNA-PDE5 group(all P<0.05).Myocardial pathological results showed that the myocardial pathological changes were alleviated gradually in MSCs-Ad-Null group and MSCs-shRNA-PDE5 group.qRT-PCR results showed that compared with sham operation group,the expression of PDE5 mRNA increased,and the expressions of cGMP and PKG mRNA decreased in model group and MSCs-Ad-Null group(all P<0.05).According to the order of model group,MSCs-Ad-Null group and MSCs-shRNA-PDE5 group,the expression of PDE5 mRNA decreased gradually,and the expressions of cGMP and PKG mRNA increased gradually(P<0.05,P<0.01).Conclusion MSCs with PDE5shRNA can improve cardiac function,alleviate myocardial pathological changes and myocardial fibrosis after MI and inhibit ventricular remodeling by regulating the expressions of PDE5,cGMP and PKG.