Altered expression of vascular endothelial growth factor and its receptor in the kidneys of patients with type 2 diabetic nephropathy

Objective:To evaluate the distribution and expression of vascular endothelial growth factor(VEGF)and its receptor(VEGF R)in the kidneys of patients with type 2 diabetic nephropathy(DN)and their relationship with clinical and pathological manifestations. Methodology:30 patients with renal biopsy proven DN were enrolled in this study,whose renal tissue were subjected to immunohistochemical staining by 4 layed PAP method using monoclonal anti VEGF and anti VEGF R antibodies.Residual normal renal tissue from nephrectomy was served as control.The relationship of expression pattern of VEGF and its receptor and clinicopathological manifestation was also investigated. Results:It was found that there were a strong differences in both of the distribution and staining intensity of VEGF and VEGF R in the kidneys of patients with DN as compared with normal controls.Upregulated glomerular VEGF expression closely associated with the glomerular endothelial proliferation(66 6% vs 33 3%, P 0 05),microaneuyrism formation(61 6% vs 25 0%, P 0 05)and nodular lesions(72 2% vs 16 7%, P 0 05).VEGF upregulation also correlated to marked proteinuria(Upro≥3 0 g/d,76 5% vs 38 5%, P 0 05)and diabetic retinopathy(58 8% vs 23 1%, P 0 05).No relationship of VEGF upregulation with hypertension or uncontrolled HbA 1c was found. Conclusion:Upregulated glomerular VEGF expression closely associated with marked proteinuria,diabetic retinopathy and glomerular endothelial lesions in patients with DN.VEGF may participate in the glomerular endothelial impairment and the increased capillary permeability of glomeruli in patients with DN.