Oxidative stress in the red blood cells of patients with primary open-angle glaucoma

BACKGROUND: This study was designed to examine oxidative and antioxidative changes in the red blood cells (RBCs) of patients presenting with glaucomatous degeneration. METHODS: The experimental design was a case-control study of strictly selected patients who required antiglaucomatous surgery during primary open-angle glaucoma despite relatively regulated intraocular pressure (IOP) (POAGgroup, n = 30) and patients who underwent an operation for nonpathological cataracts (cataract group, n = 25). The activities of total superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT), as well as the concentration of malondialdehyde (MDA), were measured. Glaucomatous damage was estimated from a transient pattern electroretinogram. RESULTS: Significant increases in GPX (p = 0.026) and CAT (p = 0.000) activity were noted in the RBCs of POAG patients compared to those of cataract patients. Although SOD was elevated in patients with POAG, the differences compared to cataract controls were not significant (p = 0.079). MDA concentrations were significantly increased in the glaucoma group compared to the cataract controls. CONCLUSION: An oxidative disorder primarily represented by catalase upregulation was observed during the course of glaucoma.