Effect of 17ß­estradiol in rat bone marrow­derived endothelial progenitor cells.

The aim of the present study was to investigate the bionomics of rat bone marrow endothelial progenitor cells (EPCs) following 17ß­estradiol treatment at various concentrations. Total mononuclear cells were extracted from rat bone marrow by density gradient centrifugation. Following cultivation for 7 days, attached cells were incubated with various concentrations of 17ß­estradiol (0, 10 and 100 nmol/l). The proliferation and migration activities of EPCs were measured by MTT and transwell chamber assays. In vitro vasculogenic activities were measured using type I collagen. Flow cytometry was performed to analyze differentiation into endothelial cells. The results indicated that at 7 days following culture, CD133 and CD34 cell markers were 69.44 and 81.05%, respectively. MTT assay demonstrated that the optical density (OD) value of the 10 nmol/l group was markedly higher than that of the 0 and 100 nmol/l groups. The OD value of the 0 nmol/l group was higher than the 100 nmol/l group (P<0.05). EPC migration, in vitro vascularization and differentiation were higher in the 100 and 10 nmol/l groups compared with the 0 nmol/l group. These parameters were higher in the 100 nmol/l than the 10 nmol/l group (P<0.05). In conclusion, the results of the present study demonstrated that migration, in vitro vasculogenesis and differentiation into endothelial cells is regulated by 17ß­estradiol and enhanced in a concentration-dependent manner. Proliferation levels were contrary to these observations, with levels decreasing as the concentration of 17ß­estradiol increased.