Abstract
The SDF-1/CXCR4 signaling plays a critical role in the trafficking of mesenchymal stem cells (MSCs) to the sites of tissue damage. Our recent study demonstrated that atorvastatin (ATV) treatment improved the survival of MSCs, and ATV pretreated MSCs (ATV-MSCs) exhibited enhanced engraftment to injured myocardium. In this study, we investigated whether combined treatment with ATV and ATV-MSCs enhances cardiac repair and regeneration by activating SDF-1/CXCR4 signaling in a rat model of acute myocardial infarction. Rats were randomized into eight groups: the Sham, AMI control and 6 other groups that were subjected to AMI followed by treatment with MSCs, ATV, ATV+MSCs, ATV-MSCs, ATV+ATV-MSCs, ATV+ATV-MSCs+AMD3100 (SDF-1/CXCR4 antagonist), respectively. ATV+ATV-MSCs significantly potentiated targeted recruitment of MSCs to peri-infarct myocardium and resulted in further improvements in cardiac function and reduction in scar size compared with MSCs treatment alone at 4-week after AMI. More importantly, the cardioprotective effects conferred by ATV+ATV-MSCs were almost completely abolished by AMD3100 treatment. Together, our study demonstrated that ATV+ATV-MSCs significantly enhanced the targeted recruitment and survival of transplanted MSCs, and resulted in subsequent cardiac function improvement by augmenting SDF-1/CXCR4 signaling.