Effects Of HIF-1? Gene Modified Cardiac Stem Cells Transplantation On Cardiac Function After Myocardial Infarction In Rats

Objective: To study the effects of the hypoxia inducible factor 1 alpha gene modified cardiac stem cell transplantation and simple cardiac stem cell transplantation,on cardiac function in rats with ischemic heart failure,cardiac stem cell survival rate,the capillaries and myocardial cell apoptosis in the edge of the infarct area.Methods:1 The culture of cardiac stem cells :1 day old SD male rats were used for isolation,identification and purification of cardiac stem cells.2 Recombinant adenovirus infecting cardiac stem cells.HIF-1? mRNA expression in cardiac stem cells was detected by RT-qPCR.3 The ischemic heart failure model:24 SD rats were randomly divided into 3 groups: HIF-1? modified cardiac stem cell group,cardiac stem cell group and model group.The model of myocardial infarction was established by ligating the LAD coronary artery by thoracotomy.After 2 weeks,the cardiac stem cells,cardiac stem cells and PBS solution were injected respectively.4 After 4 weeks,the following indexes were collected: the cardiac function was measured by echocardiography.The survival rate of CSCs was observed by fluorescence microscope and the CSCs density was calculated.Myocardial pathological changes were evaluated by HE staining.Detection of myocardial apoptosis rate by TUNEL.Western Blot method was used to detect the expression of VEGF protein.The expression of CD31 was detected by immunohistochemical staining,and the capillary density was calculated.Correlation between LVEF and cardiac stem cell survival density.Results:1 The primary cultured rat heart tissue block 7~8 days,round,small volume,strong refraction of cardiac stem cells began to climb out from the tissue edge;2 Because of the anti-c-kit antibody and streptavidin-FITC labeling,the c-kit + CSCs can be clearly seen at 490 nm wavelength.C-kit + CSCs can be identified and recovered by flow cytometry,and the purity of CSCs is about13%.Culture the CSCs to the third generation;3 Recombinant adenovirus could successfully infect CSCs,and the cardiac stem cells was grew well.When the MOI value reached to 300,the infection efficiency was the best.In HIF-1?-EGFP+CSCs group(4.483±0.156),the mRNA transcription of HIF1?gene was significantly higher than that of EGFP+CSCs group(1.007±0.13)and CSCs group(1.18±0.03)(P<0.05);4 After 4 weeks of transplantation,the heart fuction was significant difference among three groups.Left ventricle of the fraction ejection were as follows :the model group(31.51±4.34),MI+CSCs+HIF1?group(43.99±4.95)and MI+CSCs group(39.41±3.72).The LVEF was more significant higher in group MI+CSCs+HIF1?(P<0.05);5 4 weeks after transplantation,the cardiac stem cell survival rate in MI+CSCs+HIF1? group(12.391±1.881)was significantly higher than that of group MI+CSCs(6.756±1.181)(P<0.05).The difference of LVEF before and after transplantation was positively correlated with the survival rate of CSCs(r=0.867,P<0.01);6 4 weeks after transplantation,apoptotic cells were found in the 3 group,the apoptosis rate in MI+CSCs+HIF1? group(47.40±3.06)% and MI+ CSCs group(53±3.65)% were decreased(P<0.05),and the apoptosis rate of MI+CSCs group was significantly lower than that of group MI(61.20±3.91)%(P<0.05);7 4 weeks after transplantation,The VEGF protein expression increased significantly(P<0.01)in CSC+HIF1?+MI group(4.747±0.969)than the MI group(1.17±0.088),and the capillary density was significantly higher in MI+CSCs+HIF1?group(12.82±0.86)than that of MI+CSCs group(8.86±1.08)(P<0.05).Conclusion:1 Transplantation of HIF1? gene modified CSCs and Cardiac stem cell transplantation can improve cardiac function in rats with heart failure after myocardial infarction,reduce myocardial apoptosis,and promote peripheral vascular regeneration in myocardial infarction rats.Among them,HIF1? gene modified CSCs effect is more significant.2 Left ventricular ejection fraction was positively correlated with the survival rate of cardiac stem cells.3 CSCs was infected with recombinant adenovirus HIF-1? and EGFP,which could increase the expression of HIF1? mRNA and protein content in CSCs.