Small Molecules that Induce Cardiomyogenesis in Embryonic Stem Cells

摘要

Stem cells are multipotent cells with the ability to self-renew and differentiate into specialized cells in response to appropriate signals. Most tissues have endogenous stem/progenitor cells which, upon injury to the organ, can proliferate and differentiate at the damaged site. The adult heart is composed mainly of postmitotic and terminally differentiated cells. Although a subpopulation of myocardial cells with cardiac stem cell character was identified recently, their limited availability hinders therapeutic applications. Stem cells derived from other tissues, such as bone marrow, have been shown to be capable of repairing heart damage in animal models, but inefficient differentiation and possible fusion with somatic cells limit their use in cardiac repair. Pluripotent embryonic stem (ES) cells represent a possible unlimited source of functional cardiomyocytes. However, the in vitro differentiation of ES cells into cardiomyocytes involves a poorly defined, inefficient, and relatively nonselective process. Consequently, the development of new approaches for the directed differentiation of ES cells into cardiomyocytes will likely facilitate therapeutic application of ES cells in heart disease, as well as provide important tools for probing the molecular mechanism of cardiomyocyte differentiation and heart development.