Correlation Between Circulating Endothelial Progenitor Cells And Coronary Stenosis With Patients After Myocardial Infarction

Objectives: The repaire capacity of myocardial cells is extremely limited, so after myocardial infarction the myocardial cells with complete function losed,damaged myocardium repaired by fibrous scar tissue,this lead to ventricular remodeling,rapid decline in cardiac function,and heart failture. The aim of present study is to measure the number of circulating EPCs in patients after myocardial infarction to see if there is a relationship between number of EPCs and angiographically determined severity of coronary artery disease, as well as cardiovascular risk fctors;explore the method for isolation ,cultivation and precisely identify EPCs;prove that EPCs can be induced by 5-aza to differentiated into cadiomyocyte, We hope to find a new source of cellular cardiomyoplasty and provide experimental and theoretical basis for EPCs transplantation for treating heart failure after myocardial infarction.Material and methods: (1) One hundred and one patients undergoing cardiac catheterization in lihuili hospital during septemper 2008 and octtober 2009 were enrolled in the study.Number of circulating EPCs was measured by fluorescent-activated cell sorter (FACS),analysis the relationship between number of EPCs and angiographically determined severity of coronary artery disease, as well as cardiovascular risk fctors.(2) Isolating, culturing and identifiing EPCs: the EPCs was isolated and cultured by the method of Ficoll density gradient centrifugation and adhering to the culture flask. Primary cells were taken immunofluorescence,andCD14,CD45,CD34,CD105,CD14,CD44,CD31,CD133,VEGFR with immunocytochemistry method .(3) Induced EPCs in vitro. Primary cells were induced by 5-aza. On the 7th,14th,21st,28th day, use immunocytochemistry method to determine the cardiac-specific phenotype.and RT-PCR method to detect the expression of cardiac-specific genes Nkx-2.5,GATA4,ANP. The results using SPSS13.0 statistical software with statistical analysis, P<0.05 mean significant difference between.Result:Compared with patients normal coronary artery, the number of Circulating EPCs was significantly reduced among patients after myocardial infarction(p <0.05), The number of EPC sinversely correlated with age(P=0.012) Diabetes (P = 0.036), smoking history (P = 0.001), hyperlipidemia (P = 0.045).We also observed that hypertension , family history of CAD and sex showed infection on the number of EPCs, however, no significant difference . Induced cells became bigger and longer. The connection of the cells was formed. The direction of cell arraying was gradually similar. The cells were stained positively for Troponin T and RT-PCR results showed expression of cardiac-specific genes Nkx-2.5,GATA4,ANP.Conclusion: Among patients after myocardial infarction,the reduced number of circulating EPCs correlates with the severity of coronary stenosis and the cardiovascular risk factors. EPCs may differentiate into cardiomyocytes.