Impact of Bone Marrow Mesenchymal Stem Cells That Express Vascular Endothelial Growth Factor on Cardiac Function After Myocardial Infarction

Abstract

Transplanted bone marrow mesenchymal stem cells (MSCs) can differentiate into cardiomyocytes and may have the potential to replace necrotic cardiomyocytes resulting from myocardial infarction (MI). Here we established a method for transfection of MSCs with an expression vector encoding human vascular Eedothelial Ggowth Ffctor (hVEGF). We evaluated the impact of transplantation of transfected MSCs on the recovery cardiac function and angiogenesis in a rat model of MI. Rat MSCs were separated by density gradient centrifugation; their specific surface markers were examined as was their ability to differentiate. MSCs were then transfected with pcDNA 3.1-hVEGF 165 or control-containing liposomes. Rats in the experimental MI groups received transfected MSCs, MSCs alone, or gene-transfection alone; controls included a no intervention MI group and a group that was not subjected to ischemia. Among the results, MSCs were successfully isolated and cultured. Among the intervention groups, those that received transplantation of MSCs expressing hVEGF 165 included the smallest areas of infarction and demonstrated the best recovery of cardiac function overall. Moreover, capillary density detected in this group was significantly greater than in the control group and likewise greater than in rats transplanted with MSCs alone. BrdU and Troponin-T staining revealed differential increases in the number of viable cardiomyocytes within the infarction areas; some cardiomyocytes were double-positive. Likewise, evaluation using RT-PCR revealed higher expression levels of hVEGF in rats transplanted with transfected cells compared to those treated with gene transfection alone.