Aqueous concentrations of VEGF and soluble VEGF receptor-1 in diabetic retinopathy patients

Background: the aim of this study was to simultaneously measure the concentrations of vascular endothelial growth factor (vegf) and soluble vegf receptor-1 (svegfr-1, also known as sflt-1) in the aqueous humor of patients with non-proliferative diabetic retinopathy (npdr) and to investigate whether aqueous levels of vascular endothelial growth factor (vegf) and vegfr-1 are related to diabetic macular edema. materials and methods: aqueous humor was collected from 27 diabetic patients and 33 age- and sex-matched normoglycemic controls and analyzed for pro-angiogenic vegf and angiogenic inhibitor vegfr-1 by enzyme-linked immunosorbent assay (elisa). the mean foveal thickness was measured by optical coherence tomography (oct). results: there was no significant difference in the aqueous levels of vegf in patients with npdr compared with control subjects (p > 0.05), while the npdr patients had significantly lower svegfr-1 in their aqueous humor. furthermore, a significant (p < 0.01) positive correlation was observed between vegf/svegfr-1 concentration and the mean foveal thickness measured on oct. conclusion: the results suggest that decreased chelating effect of svegfr-1 may be the preliminary event allowing vegf to activate the proangiogenic endothelial cell state and to induce permeability. the imbalance between angiogenic agent (vegf) and the antiangiogenic factors (sflt-1), which is disturbed in the diabetic state, may determine the fate of diabetic macular edema.