Mechanisms and significance of progenitor cell reduction in the metabolic syndrome.

Bone marrow-derived progenitor cells are involved in the homeostasis of the cardiovascular system through differentiation into endothelium, smooth muscle, and cardiomyocytes. Alterations of these extremely plastic cells have been recognized as both markers of cardiovascular risk and pathophysiological links between risk factors and development of atherosclerosis. Metabolic syndrome, as a cluster of well-defined cardiovascular risk factors, represents a strong predictor of cardiovascular events and death. Moreover, components of the syndrome interact with one another and synergistically increase this risk. Here we describe all metabolic syndrome components as being characterized by alterations in circulating progenitor cells, especially endothelial cells. We also highlight how endothelial progenitors may mediate the interactions between cardiometabolic risk factors in a complex interplay and discuss potential implications for prevention and therapy.