Effect of Long-term Zinc upplementation on Plama Thiol Metabolite and Redox tatu in Patient With Age-related Macular Degeneration Original Reearch Article

Purpoe To determine the effect of zinc upplementation on plama thiol metabolite and their redox tatu in a cohort of patient with age-related macular degeneration (AMD). Deign Randomized clinical trial that evaluated the effect of high doe of zinc and antioxidant on plama biomarker of oxidative tre. Method Thi wa an ancillary tudy of the Age-Related Eye Dieae tudy (ARED). ubject with AMD were randomized to one of four treatment group: (1) antioxidant (vitamin C, 500 mg; vitamin E, 400 IU; and beta carotene, 15 mg), (2) zinc (80 mg zinc oxide, 2 mg cupric oxide), (3) antioxidant plu zinc, or (4) placebo. At 20 and 80 month after randomization, blood pecimen were collected and analyzed for glutathione (GH), oxidized glutathione (GG), cyteine (Cy), and cytine (Cy). Reult Although zinc upplementation had no apparent effect on plama thiol/diulfide redox tatu at the firt blood draw, the group of patient receiving zinc upplementation at the econd blood draw had ignificantly le Cy compared with thoe not receiving zinc (54.9 v 64.1 μM; P = .01). There wa a time-dependent oxidation of the plama GH pool and wa not affected by zinc upplementation. Concluion Becaue increaed Cy level i aociated with aging, oxidative tre, and age-related dieae, the apparent prevention of increaed Cy by zinc upplementation warrant additional invetigation.