Stem Cells for Myocardial Regeneration

Cho, Myeong Chan

Abstract

Congestive heart failure is the most common ultimate consequence of many primary cardiovascular diseases. Despite significant advances in the understanding of its pathophysiology, and the development of improved medical therapies, it remains a major concern and a growing public health problem. Previously adult hearts were considered incapable of repair, but recently the role of replicating endogenous cardiomyocytes, and the recruitment of other cells (including stem cells), for myocardial regeneration has attracted much attention. There is now growing evidence that stem cells derived from numerous sources, such as embrygnal stem cells, bone marrow-derived (mesenchymal, hematopoietic and endothelial), neural and hepatocyte stem cells, are potential therapeutic options for the treatment of heart failure. It has been shown that stem cells survive and retain the capacity to differentiate into functional endothelial cells, smooth muscle cells and cardiomyocytes when transplanted into the myocardium of various species, including mice, rats, rabbits, and dogs. Stem cells have been introduced by direct intramyocardial injection, intracoronary infusion and systemic intravenous administration. Furthermore, the grafted cells have been reported to support myocardial regeneration following infarction, and improve cardiac function in experimental heart failure models. With recent major advances concerning the biology of adult stem cells (plasticity or transdifferentiation, milieu-dependent differentiation, immunotolerance of stem cells, and possibility of the presence of cardiac stem cells), stem cell transplantation is thus promising for the treatment of end-stage heart failure.