Cardiac Stem Cells and Mechanisms of Myocardial Regeneration

Abstract

This review discusses current understanding of the role that endogenous and exogenous progenitor cells may have in the treatment of the diseased heart. In the last several years, a major effort has been made in an attempt to identify immature cells capable of differentiating into cell lineages different from the organ of origin to be employed for the regeneration of the damaged heart. Embryonic stem cells (ESCs) and bone marrow-derived cells (BMCs) have been extensively studied and characterized, and dramatic advances have been made in the clinical application of BMCs in heart failure of ischemic and nonischemic origin. However, a controversy exists concerning the ability of BMCs to acquire cardiac cell lineages and reconstitute the myocardium lost after infarction. The recognition that the adult heart possesses a stem cell compartment that can regenerate myocytes and coronary vessels has raised the unique possibility to rebuild dead myocardium after infarction, to repopulate the hypertrophic decompensated heart with new better functioning myocytes and vascular structures, and, perhaps, to reverse ventricular dilation and wall thinning. Cardiac stem cells may become the most important cell for cardiac repair.

Qualitative and quantitative analysis of rabbit's fat mesenchymal stem cells

“…The cells on culture were also show to be able to adhere on culture bottle, extending and converging like a tissue, forming a fibroblastoid colony (CFU-F), like other authors have observed [13][14][15][16] .…”

A safety and feasibility study of cell therapy in dilated cardiomyopathy

“…Larger randomized trials have confirmed the efficacy of this new therapy (28)(29)(30), although these results have been disputed (31). The beneficial effects of cell therapy in the setting of ischemic heart disease are not fully understood, and proposed mechanisms of action have included new myocyte formation, angiogenesis and secretion of trophic and anti-apoptotic factors by the mononuclear cell fraction of bone marrow (17,32). The capacity of bone marrow cells to regenerate myocytes has been a matter of intense debate (7,17,(32)(33)(34)(35)(36).…”

Limited plasticity of mesenchymal stem cells cocultured with adult cardiomyocytes

“…Several studies have reported that animals injected after an experimental infarction with autologous or etherologous MSCs have an improved recovery [Leri et al, 2005].…”

“…In particular, regarding heart repair, they have been shown to potentially originate both endothelial vascular cells and cardiomyocytes. Among the different strategies proposed to promote in vitro cardiac differentiation of MSCs, chronic exposure to 5-azacytidine has been amply tested [reviewed by Leri et al, 2005], as well as stimulation by exogenous cytokines and growth factors [Xaymardan et al, 2004, Shim et al, 2004, and coculture with neonatal cardiac cell [Lagostena et al, 2005] or immortalized cardiac cell lines [Rangappa et al, 2003]. Cocultures between MSCs and adult cardiomyocytes were performed mainly to show functional connection between the two cell types [Valiunas et al, 2004].…”