Mesenchymal Stem Cells Promote Cardiac Muscle Repair via Enhanced Neovascularization

Background/Aims: Transplantation of bone-marrow derived stem/progenitor cells has an established therapeutic effect on cardiac muscle repair after injury. However, the exact mechanism that underlies this phenomenon is not completely understood. Methods: Here we transplanted mesenchymal stem cells (MSCs), a major population from the bone-marrow derived stem/progenitor cells, and studied its effects on cardiac muscle repair after injury. Results: MSCs transplantation significantly improved cardiac muscle repair after injury. The grafted MSCs did not significantly differentiate into cardiac muscle cells themselves, but appeared to induce neovascularization in the injured heart. In a loss-of-function experiment, we further show that production and secretion of placental growth factor, but not vascular endothelial growth factor A in MSCs, were essential for the MSCs-induced neovasularization after cardiac muscle injury to facilitate cardiac muscle repair. Conclusion: Our study thus sheds light on an undescribed role of placental growth factor in cardiac muscle regeneration