Circulating endothelial progenitor cells from healthy smokers exhibit impaired functional activities

Abstract Objective : Endothelial dysfunction is one of the earliest pathological effects of cigarette smoking. It has recently been suggested that endothelial progenitor cells (EPCs) could contribute to ongoing endothelial maintenance and repair. Accordingly, we tested the hypothesis that cigarette smoking is associated with EPC dysfunction. Methods and results : EPCs were isolated from the peripheral venous blood of 15 healthy smokers and 11 age-matched nonsmokers. The number of EPCs was significantly reduced in smokers versus control subjects (51.6 ± 1.9 versus 120.3 ± 10.0 per power field, p p p p Conclusions : Cigarette smoking is associated with a reduced number of EPCs together with an important impairment of EPC differentiation and functional activities. Our results suggest that EPC dysfunction could contribute to impair blood vessel healing and growth in smokers.