Different Plasma Levels of Vascular Endothelial Growth Factor and Nitric Oxide between Patients with Choroidal and Retinal Neovascularization

Abstract

Because the blood flow is much more intense in the choroid than in the retina, it is interesting to explore whether choroidal neovascularization (CNV) is more influenced by plasma angiogenic factors than retinal neovascularization. The aim of this study was to investigate plasma profiles of vascular endothelial growth factor (VEGF) and nitric oxide (NO) in patients with CNV due to age-related macular degeneration (AMD) and in those with retinal neovascularization due to proliferative diabetic retinopathy (PDR). Seventy-seven subjects with AMD, 22 with PDR, and 42 nondiabetic, non-AMD controls were enrolled in this comparative case series. AMD subjects were classified into three groups: dry type (dry AMD, n = 17), wet type with active CNV (CNV/AMD, n = 42), and disciform scar due to advanced wet AMD (scar/AMD, n = 18). Plasma VEGF and NO levels of each subject were measured with enzyme-linked immunosorbent assay and chemiluminescence, respectively. Plasma VEGF level in CNV/AMD (median 256.0 pg/ml, interquartile range 146.4–375.3 pg/ml) was significantly higher than in PDR (124.8 pg/ml, 75.7–215.3 pg/ml; p = 0.004) and controls (120.3 pg/ml, 82.8–168.2 pg/ml, p =0.001). CNV/AMD also had the highest VEGF level among the AMD subgroups. Plasma NO level was significantly elevated in PDR (137.4 µM, 63.7–240.1 µM) when compared with CNV/AMD (71.8 µM, 42.4–113.3 µM; p = 0.004) and controls (62.6 µM, 39.0–114.9 µM; p = 0.002). There was no significant difference in NO levels among the AMD subgroups. No significant correlation between VEGF and NO levels was noted. These findings indicate that both circulating VEGF and NO may play different roles in the pathogenesis of retinal neovascularization and CNV.

Endothelial Progenitor Cells and Plasma Vascular Endothelial Growth Factor and Stromal Cell-Derived Factor-1 During Ranibizumab Treatment for Neovascular Age-Related Macular Degeneration

“…First, we have found pretreatment plasma VEGF levels in the reported ranges for patients with nvAMD (a median of 208 24 or 256 pg/mL, 25 respectively, or 218.4 -59.3 pg/mL for active disease 37 ).…”

“…23 Interestingly, in AMD, VEGF plasma levels are even significantly higher than in proliferative diabetic retinopathy. 24,25 Another cytokine shown to induce mobilization of hematopoietic stem cells as well as EPCs from the bone marrow is stromal cell-derived factor 1 (SDF-1). 26,27 In the search for potential circulating biomarkers, a range of recent studies in cancer patients have evaluated EPCs as well as blood levels of VEGF and other cytokines during systemic therapy with bevacizumab or other antiangiogenic therapeutics (for an overview, see Ref.…”

Genetic markers and biomarkers for age-related macular degeneration

“…Interestingly, these researchers found significantly higher plasma VEGF levels in wet AMD patients compared with dry AMD patients (p < 0.05) [59]. These results suggest that high VEGF levels may play a role in predisposing individuals to NV AMD.…”

Development of Laser-Induced Choroidal Neovascularization in Rats after Retinal Damage by Sodium Iodate Injection

“…SI destroys the zonula occludens, the anatomic basis for the blood-retinal barrier [22] . Rupture of the RPE barrier may allow a higher concentration of proangiogenic growth factors from the plasma [23] . Another possible mechanism may be related to the presence of inflammatory cells, such as macrophages that are present in the retina 3 days after intravenous injection of SI, probably as a response to the retinal damage caused by SI [24] .…”