Diabetic retinopathy (DR), a DM microvascular complication, is the leading cause of blindness. Angiogenic factors such as vascular endothelial growth factor (VEGF) are involved in the pathogenesis of DR. VEGF-A is a potent, multifunctional cytokine that acts through the receptors VEGFR-1 and VEGFR-2 expressed in the vascular endothelium and causing increased vascular permeability and neovascularization stimulation in both physiological and pathological processes. The expression of VEGFR-1 is upregulated by hypoxia and is less responsive to VEGF compared to VEGFR-2 which is the main mediator mitogenic, angiogenic, and increased vascular permeability. VEGF polymorphisms have been studied in DR susceptibility and progression. Significant association between the polymorphism 634C / G and the presence of RD is reported mainly in relation to allele C. The homozygous CC is associated to proliferative RD and to increased vitreous and serum levels of VEGF suggesting that the presence of the C allele is an independent risk factor for RD. The knowledgement of VEGF lead to the development of anti-VEGF drugs (pegaptanib, ranibizumab and bevacizumab) aiming to prevent pathological neovascularization. The anti-VEGF therapy is a reality in practice medical treatment of DR.
Diabetes mellitus; diabetic retinopathy; vascular endothelial growth factor; polymorphism
