Enhanced therapeutic effects of mesenchymal stem cells on myocardial infarction by ischemic postconditioning through paracrine mechanisms in rats.

Abstract Ischemic postconditioning (IPC) is cardioprotective against ischemia–reperfusion injury which impairs the myocardial micro-environment and reduces the survival of transplanted cells. We tested the hypothesis that IPC may improve the survival of transplanted cells and enhance their therapeutic effects. In this study, bone marrow-derived mesenchymal stem cells (BMSCs) from Sprague–Dawley rats were infected with lentivirus carrying green fluorescent protein (GFP) gene. The left main coronary arteries of rats were occluded for a 30-min ischemia, followed by a 72 h or 28 d reperfusion. IPC was induced by 3 cycles of 10 s reperfusion and 10 s ischemia before sustained reperfusion. GFP–BMSCs were intramyocardially injected at 2 h reperfusion. At 70 h after transplantation, IPC treatment increased the level of interleukin-10, B-cell leukemia-lymphoma-2 (BCL-2), and vascular endothelial and basic fibroblast growth factor (VEGF and bFGF), and decreased the level of tumor necrosis factor-α, interleukin-1β and BCL-2-associated X protein by ELISA or PCR or western blotting. The BMSCs therapy with IPC produced more surviving GFP-positive cells than the BMSCs therapy alone by fluorescent staining [at 70 h, (90 ± 14)/mm 2 vs. (61 ± 12)/mm 2 , and at 28 days, (55 ± 14)/mm 2 vs. (26 ± 8)/mm 2 , P