Overexpression of MicroRNA-1 Improves the Efficacy of Mesenchymal Stem Cell Transplantation after Myocardial Infarction

Background: The aim of this research was to study whether transplantation of mesenchymal stem cells (MSCs) overexpressing microRNA-1 into mouse infarcted myocardium can enhance cardiac myocyte differentiation and improve cardiac function efficiently. Methods: Eight-week-old female C57BL/6 mice underwent ligation of the left coronary artery to produce models of myocardial infarction. The ligated animals were randomly divided into 4 groups (20 in each). One week later, they were intramyocardially injected at the heart infarcted zone with microRNA-1-transduced MSCs (MSCmiR-1 group), mock-vector-transduced MSCs (MSCnull group), MSCs (MSC group) or medium (PBS group). At 4 weeks post-transplantation, transthoracic echocardiographic assessment, histological evaluation and Western blot were performed. Results: The transplanted MSCs were able to differentiate into cardiomyocytes in the infarcted zone. Cardiac function in the MSC, MSCnull and MSCmiR-1 groups was significantly improved compared to the PBS group (p < 0.01 or p < 0.001). However, treatment of MSCs expressing microRNA-1 was more effective for cardiac repair and improved cardiac function more efficiently by enhancing cell survival and cardiac myocyte differentiation compared to the MSC group or the MSC null groups (p < 0.05 or p < 0.01, respectively). Conclusions: Transplantation of microRNA-1-transfected MSCs was more conducive to repair of infarct injury and improved heart function by enhancing transplanted cells survival and cardiomyogenic differentiation. Copyright (C) 2013 S. Karger AG, Basel