Association between oxidative stress and macromolecular damage in elderly patients with age-related macular degeneration

BACKGROUND AND AIMS: The aim of the present study was to determine whether age and gender affect the imbalance between oxidant production and antioxidant levels in age-related macular degeneration (ARMD) patients. METHODS: Total superoxide dismutase (T-SOD), total glutathione peroxidase (T-GSHPx), and catalase (CAT) activities, as well as malondialdehyde (MDA), protein carbonyl (PC), 8-Hydroxy-29-deoxyguanosine (8-OHdG) and total oxidation status (TOS) levels, were measured in the following groups subdivided by age and gender: 156 early-ARMD patients; 80 wet-late ARMD patients; 72 dry-late ARMD patients; and 207 healthy controls. RESULTS: Among all study participants, women aged 50-54 had higher T-SOD and T-GSHPx activities and lower MDA, PC, TOS and 8-OHdG levels than age-matched men (p<0.05), whereas older women were not significantly different from agematched older men. Significantly increased oxidative damage was associated with ARMD patients >60 years of age in both sexes compared with controls (p<0.01 for 60-64 and 65-69-year-old ARMD subgroups; p<0.001 for 70-74 and 75-80-year-old ARMD subgroups). Multiple regression analysis demonstrates that age significantly affects antioxidant status and oxidative damage in ARMD patients compared with controls (controls, p<0.05; ARMD patients, p<0.001). A direct correlation with antioxidant enzyme activities and an inverse correlation with oxidative DNA, protein and lipid damage were also observed in premenopausal women (controls, p<0.05; ARMD patients, plt;0.001). CONCLUSIONS: Aging and postmenopausal status may be aggravating factors contributing to redox imbalance and oxidative damage in ARMD patients.