Effect of simvastatin on the quantity and function of human umbilical cord blood-derived late endothelial progenitor cells

Objective:To investigate the effect of simvastatin on the quantity and function of late endothelial progenitor cells(EPCs)from human umbilical cord blood in vitro.Method:Mononuclear cells were isolated from human umbilical cord blood by density gradient centrifugation and cultured on fibronectin-coated culture flask, then the cells cultured in EGM-2MV medium differentiated into late EPCs which were identified by flow cytometry and fluorescent staining.The good growth state of late EPCs of second generation were treated with simvastatin in a series of concentrations(10-8,10-7,10-6,10-5 mol/L)for 24,48,72hand the proliferation,adhesion and tubule-formation activity of EPCs were analyzed by CCK-8reagent kit,adhesive assay and tubule-formation assay respectively.Result:Late EPCs were isolated and cultured successfully from human umbilical cord blood.Com- pared with control group,lower concentrations of simvastatin(10-8,10-7,10-6 mol/L)significantly promoted cell proliferation,adhesion and in vitro vascularization and the concentration of 10-7 mol/L was the most prominent,while higher concentration(1 0-5 mol/L)inhibited the functions above.Simvastatin increased the proliferative capacity of EPCs in a time dependent manner,but adhesion and tubule-formation activity were the most prominent at 48h.Conclusion:Simvastatin enhances the count of late EPCs and improve cell functions remarkably at lower concentrations,while higher concentration elicit inhibitory effects.