P5386Transplantation of endothelial progenitor cells in the treatment of coronary artery microembolism in rats

Objective As the impairment of myocardial micro-environments due to coronary micro-embolization (CME) compromises the treatment effect of percutaneous coronary intervention and leads to adverse prognosis, we hypothesized that endothelial progenitor cells (EPCs) transplantation could improve cardiac function in the condition of CME. Materials and methods Low- (2×105) and high- (2×106) dose rat bone marrow-derived EPCs were transplanted in a model of CME. To develop a CME model, rats were injected with autologous micro-blood clots into the left ventricle. Echocardiography was examined before and 1, 7, and 28 days after EPC transplantation; serum cTNI, vWF,and cardiac microRNA expression were examined one day after EPCs transplantation. Heart morphology and VEGF, vWF, and bFGF expression were examined one day after EPC transplantation. Figure 1. Results Results After 10 days of culture inductions, BM-EPCs have high purity as confirmed by flow cytometry. Cardiac function reflected by LVEF significantly decreased after CME treatment and rescued by low-dose EPC. Compared to the sham group, cTNI, and vWF serum levels increased significantly after CME treatment and rescued by low-dose EPC and high-dose EPC. Low-dose EPC treatment decreased myocardial necrosis and fibrosis and elevated cardiac expression of VEGF and vWF, while decreasing the cardiac expression of bFGF. Low-dose EPC treatment significantly suppressed cardiac expression of microRNA-19a but significantly enhanced microRNA-21, microRNA-214, and microRNA-486-3p expression. In conclusion, our results indicate that low-dose EPC transplantation may play a pro-angiogenic, anti-fibroblast, anti-fibrosis, and anti-necrosis role and enhance cardiac function in a rat model of CME through a microRNA-related pathway. Acknowledgement/Funding Supported by the State Key Laboratory of Low-Dimensional Quantum Physics Open Project Fund (No. KF201608)