High Glucose On Human Vascular Endothelial Progenitor Cell Proliferation Mechanism And The Impact Of The Initial Study

Diabetes is common clinical metabolic diseases,and vascular diseases are chronic complications of its main performance,which is an important impact factor on the prognosis for patients with diabetes and the quality of life.Many studies have shown that In some microvascular tissues,the result is pathologic neovascularization and increased vascular permeability.These responses account for much of the visual loss associated with diabetic retinopathy(DR).The function of neovascularization in DR is imperfect,thus leading to repeated vitreous hemorrhage,fiber proliferation,retinal detachment and loss of vision. Recen studies found that angiogenesis in DR is closely related to some kind of stem cells,endothelial progenitor cells(EPCs),EPCs as multipotent stem cells can be found in self-renewal,proliferation,and differentiation of endothelial Cells.A lot of evidences show that EPCs play an important role in the formation of blood vessels,especially in ischemic conditions,Grant,etc.found that bone marrow-derived EPCs play an important role in adult retinal angiogenesis model.Experiments show that NO is also closely linked with diabetes,the number of EPCs in the peripheral blood may reduce according to NO decrease.However, in DR the role of NO and EPC have not been reported.This study was thus conducted to examine the direct effects of high glucose on the number/proliferation and differentiation of EPCs and,more importantly, to investigate the individual roles of NO mechanisms in high glucose-induced impairments,if there are any.We successfully isolated from human umbilical cord blood mononuclear cells,cultured cells with medium EGM-2MV in vitro, observed with inverted microscope,immunohistochemical staining identificated marks on the surface of CD133,KDR,vWF expression.P2 cultured cells were divided into four groups,normal control group: EGM-2MV medium culture;high glucose group:final concentration: 33 mmol/L;high glucose+L-NAME group:containing glucose concentration of 33 mmol/L EGM medium-2MV joined the endothelial nitric oxide synthase(eNOS)inhibitor L-NAME 10μmol/L;mannitol (osmotic pressure control group):-Mannitol final concentration:33 mmol/L.The samples were incubated for 48 hours,observed with CCK-8 and flow cytometry,immunofluorescence staining of cells differentiation and the expression of 3-NT protein.The cells in high glucose-treated group demonstrated the same marker as normal control group;Compared with the control group,high glucose promote EPC proliferation(p＜0.001).;Immunofluorescence assay found:3-NT protein expression was significantly increased compared with the normal control group.Together with our studies,we concluded that:high glucose may enhance cell number proliferation in EPCs,but does not affect EPCs differentiation,NO could be the main contributor to high glucose-induced EPC proliferation...