Bone Marrow–Derived Progenitor Cells Modulate Vascular Reendothelialization and Neointimal Formation

Abstract

Objective— Atherosclerosis and restenosis after vascular injury are both characterized by endothelial dysfunction, apoptosis, inappropriate endothelialization, and neointimal formation. Bone marrow–derived endothelial progenitor cells have been implicated in neovascularization, resulting in adult blood vessel formation. Despite the anticipated stem cell plasticity, the role of bone marrow–derived endothelial progenitor cells has not been clarified in vascular lesion development. Methods and Results— We investigated vascular lesion formation in mice after transplantation of bone marrow transfected by means of retrovirus with enhanced green fluorescent protein. Carotid artery injury was induced, resulting in neointimal formation. Fluorescence microscopy and immunohistological analysis revealed that bone marrow–derived progenitor cells are involved in reendothelialization of the vascular lesions. Treatment with rosuvastatin (20 mg/kg body wt per day), a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, enhanced the circulating pool of endothelial progenitor cells, propagated the advent of bone marrow–derived endothelial cells in the injured vessel wall, and, thereby, accelerated reendothelialization and significantly decreased neointimal formation. Conclusions— Vascular lesion development initiated by endothelial cell damage is moderated by bone marrow–derived progenitor cells. 3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibition promotes bone marrow–dependent reendothelialization and diminishes vascular lesion development. These findings may help to establish novel pathophysiological concepts and therapeutic strategies in the treatment of various cardiovascular diseases.