Netrin-1 Work Together With UNC5B To Regulate The Angiogenesis Of Diabetic Nephropathy

BackgroundsMany studies have found that the neural development and angiogenesis may use the same set of regulating factors.The nerve axon guidance factor1(Netrin-1)and its receptor UNC5B can not only play an important role active or repulsive in neural axon growth but also in angiogenesis.Importing the recombinant gene of netrin-1 or product in Diabetic nephropathy(DN)rats can improve proteinuria and renal protection.Diabetic retinopathy is also an diabetic vascular complications which is familiar with diabetic nephropathy,and there are more researches about the Netrin-1,UNC5B for diabetes retina(DR)abnormal angiogenesis.But the role of Netrin-1 and UNC5B in kidney angiogenesis in DN has not been studied.We purport in the study to learn the expression of Netrin-1 and UNC5B in the kidney and in vitro to learn their effect on glomerular endothelial cells(HRGECs)in the Cell migration assay and tube formation assay,and to lesm the corresponding adjustment mechanism on glomerular angiogenesis.MethodsDetect the Netrin-1 levels in the urine of patients clinical diagenosisde of DN.Detect the UNC5B expression levels in Renal biopsy of pations diagnosed DN and minimal change nephropathy and detect the UNC5B expression levels in the kidneys of Wistar mice and SD mice by immunohistochemical staining and immuno-fluorescence staining.Use a UNC5B specific si-RNA to silence the UNC5B expression in human glomerular endothelial cells(HRGEC)in vitro,and cultured with exogenous recombinant Netrin-1,VEGF-165 factors,then test the cells' effect of cell migration,proliferation or capacity of tube formation.At the same time,observe the changes of vascular endothelial growth factor(VEGF)and the of its pathway molecular.ResultsIn the kidney,UNC5B expression was mainly on the glomerular capillary endothelial cells.Netrin-1 and UNC5B were at high levels in DN group than that of the corresponding control group.In vitro,Netrin-1 could inhibit cell migration and tube formation in HRGEC.This role of inhibition was by suppressing the activation of Src to become phospho-Src.Netrin-1 could counteract the effect of VEGF-165 which could promot human glomerular endothelial cells migration and tube formation,however this effect of Netrin-1 could be neutralized by UNC5B.ConclusionsNetrin-1 could inhibit cell migration and tube formation in HRGEC with the relevant of suppressing the VEGFA/VEGFR2 Downstream pathway molecules Src to become the active partern named phosho-Src.In our research the effect of Netrin-1 could be neutralized by UNC5B.So the increased expression of UNC5B in the kidneys of DN may be one of the reason for the increase of angiogenesis in DN.Inhibit the UNC5B expression in kidney glomerular endothelial cells at the same time increase the exogenous Netrin-1 May be an effective way to curb kidney angiogenesis in DN,which could slowsdown the progress of kidney damage to ESRD.