Effects of homocysteine on number and activity of endothelial progenitor cells from peripheral blood

AIM: To investigate whether homocysteine (Hcy) has influences on endothelial progenitor cell (EPCs) number and activity from peripheral blood. METHODS: Total mononuclear cells (MNCs) were plated on fibronectin-coated culture dishes and cultured for 7 days, and then attached cells were stimulated with Hcy or vehicle control for 6 h, 12 h, 24 h and 48 h. The adhesion, proliferation, migration and in vitro vasculogenesis activity of EPCs were assayed, respectively. RESULTS: Incubation of isolated human MNCs with Hcy dose and time-dependently decreased the number of EPCs with maximum at 200 μmol/L for 24 hours (35.7±6.7 vs 62.5±10.6， P＜0.01). In addition, Hcy impaired EPC proliferative (0.531±0.061 vs 0.328±0.055， P＜0.05), migratory (26.3±6.4 vs 6.4±3.7， P＜0.01), adhesive (33.1±8.1 vs 17.4±7.5， P＜0.01) and vasculogenesis capacity (25.4±9.1 vs 10.4±4.7， P＜0.01) in a dose and time-dependent manner. CONCLUSION: It is suggested that Hcy may result in the reduction of EPCs and decrease EPC functional activity.