Therapeutic potential of human adipose stem cells in a rat myocardial infarction model

Stem cell transplantation is expected to have good effects in the treatment of myocardial infarction (MI). We tested the effect of the transplantation of human adipose-derived cells (ASCs) in Sprague-Dawley (SD) rats with myocardial infarctions.

ASCs were isolated from the waste of elective abdominal surgery. The MI model was set up in SD rats by permanent ligation of the left anterior descending coronary artery. One week after MI, either 1 x 10(6) ASCs or an equal volume of phosphate-buffered saline (PBS) was injected into the infarct zone. Cardiac function was assessed by echocardiography, 1 day, 1 week, 2 weeks, and 4 weeks after treatment. Four weeks after transplantation, immunohistochemistry was performed.

Left ventricular function, including fractional shortening (FS), and ejection fraction (EF) showed a significant improvement in the ASCs transplantation group compared to the PBS group 4 weeks after treatment (p < 0.05). The anterior wall thickness of the left ventricle was significantly thicker in the ASCs transplantation group compared to the PBS group (p < 0.01). Multiple troponin T staining, and irregular, small amounts of connexin 43 expression also was observed in the ASCs transplantation group. Infarcted myocardium showed higher capillary density in the ASCs transplantation group than in the PBS injected group (p < 0.01).

This study provides encouraging evidence that transplantation of ASCs can improve cardiac function of infarct myocardium in rat models with a limitation of cardiac remodeling, improved wall thickness, and increased neovascularization.