Effect of thrombin on proliferation of bone-marrow derived endothelial progenitor cells

Objective: To investigate the effects of thrombin on proliferation of bone-marrow derived endothelial progenitor cells(EPCs)and the underlying mechanism.Methods: EPCs were acquired from the bone marrow of SD rats by density gradient centrifugation.After 7 days of culture,EPCs were incubated with thrombin in different concentrations(10-2,10-1,1,10,100 U/mL)for different time points(6,12,24,48 h).EPCs proliferation was measured by Cell Counting Kit-8.Real time PCR was used to measure VEGF mRNA expression of EPCs after intervention by thrombin or pretreatment with NFκB inhibitor.ELISA assay was used to measure VEGF secretion.Results: EPCs proliferation was significant higher in the thrombin intervention group compared with control group,it reached a maximum at 10 U/mL after 24h of intervention(P0.05).Thrombin up-regulated VEGF mRNA level and increased the secretion,which process can be blocked by NFκB inhibitor.Conclusion: Thrombin could induce the proliferation of EPCs via increasing the expression of VEGF through NFκB pathway.