Bone marrow-derived, circulating endothelial progenitor cells (EPCs) contribute to neovascularization in various diseases, and represent a very interesting alternative cell source for enhancing vasculogenesis in regenerative medicine. In this study, we investigated the effects of Ginkgolide B (GB) on proliferation and differentiation of EPCs, and the involved signaling pathway in vitro. EPC proliferation, migration, adhesion and angiogenesis activities were assessed with the WST-8 assay,

more »

... ll chamber assay, cell counting and angiogenesis kit, respectively. Apoptosis was detected with annexin V and propidium iodide staining. The protein expression of angiogenesis-related makers was detected by Western blot, and related gene expression was determined by real-time polymerase chain reaction (RT-PCR). The results showed that GB promoted the proliferation and endothelial gene expression, and markedly enhanced vascular endothelial growth factor-induced migration response and the capability to incorporate into the vascular networks in EPCs. GB protected EPCs from H 2 O 2 -induced cell death. GB induced the phosphorylation of eNOS, Akt and p38, which in turn promoted cell proliferation and function. In conclusion, the present study demonstrates that GB, at a near medical applied dose, increases the number and functional activities of EPCs with involvement of Akt/endothelial nitric oxide synthase and mitogen-activated protein kinase (MAPK)/ p38 signal pathways. These findings raise the intriguing possibility that GB may play an important role in the protection and revascularization of blood vessels.