Aqueous Humor and Plasma Levels of Vascular Endothelial Growth Factor and Nitric Oxide in Patients With Pseudoexfoliation Syndrome and Pseudoexfoliation Glaucoma

Abstract

To investigate levels of vascular endothelial growth factor (VEGF) and nitric oxide (NO) in the aqueous humor and plasma of patients with pseudoexfoliation syndrome (PXS) and pseudoexfoliation glaucoma (PXG), compared with controls. This prospective study involved 37 patients with PXS, 15 with PXG, and 32 control subjects in whom cataract surgery was indicated. Aqueous humor and plasma VEGF and NO levels were measured with enzyme-linked immunosorbent assay and chemiluminescence methods, respectively. Aqueous humor and plasma VEGF concentrations were higher in patients with PXS and PXG than in controls (P<0.001). Aqueous humor NO concentrations were higher in patients with PXS and PXG than in controls (P<0.05 and P=0.001, respectively). Plasma NO concentrations did not differ between the 3 groups. Aqueous humor and plasma VEGF and NO levels were not significantly different in patients with PXS versus PXG. VEGF and NO levels showed no significant correlation among the 3 groups (P>0.05). Elevated aqueous humor VEGF and NO levels and plasma VEGF concentrations in eyes with PXS and PXG can be explained by the ischemic nature of these disorders. The lack of correlation between VEGF and NO levels may indicate impaired downregulation, which may have a role in the progression to PXG.