TY - JOUR
T1 - Effects of Long-term Zinc Supplementation on Plasma Thiol Metabolites and Redox Status in Patients With Age-related Macular Degeneration
AU - Moriarty-Craige, Siobhan E.
AU - Ha, Khoi Nguyen
AU - Sternberg, Paul
AU - Lynn, Michael
AU - Bressler, Susan
AU - Gensler, Gary
AU - Jones, Dean P.
N1 - Funding Information:
This study was supported by NIH Grants EY07892, EY08126, EY06360, Foundation Fighting Blindness, Owings Mills, Maryland and Research to Prevent Blindness, Inc, New York, New York. The authors indicate no financial conflict of interest. Involved in design and conduct of study (P.S., D.P.J.); Involved in collection, management, analysis and interpretation of data, and preparation of the data (P.S., S.M.-C., D.P.J.); Involved in collection of data (S.M.-C., S.B.); and involved in management, statistical analysis and interpretation of the data, and preparation of the manuscript (P.S., K.-N.H., S.M.-C., M.L., S.B., G.G., D.P.J.).
PY - 2007/2
Y1 - 2007/2
N2 - Purpose: To determine the effects of zinc supplementation on plasma thiol metabolites and their redox status in a cohort of patients with age-related macular degeneration (AMD). Design: Randomized clinical trial that evaluated the effects of high doses of zinc and antioxidants on plasma biomarkers of oxidative stress. Methods: This was an ancillary study of the Age-Related Eye Disease Study (AREDS). Subjects with AMD were randomized to one of four treatment groups: (1) antioxidants (vitamin C, 500 mg; vitamin E, 400 IU; and beta carotene, 15 mg), (2) zinc (80 mg zinc oxide, 2 mg cupric oxide), (3) antioxidants plus zinc, or (4) placebo. At 20 and 80 months after randomization, blood specimens were collected and analyzed for glutathione (GSH), oxidized glutathione (GSSG), cysteine (Cys), and cystine (CySS). Results: Although zinc supplementation had no apparent effect on plasma thiol/disulfide redox status at the first blood draw, the group of patients receiving zinc supplementation at the second blood draw had significantly less CySS compared with those not receiving zinc (54.9 vs 64.1 μM; P = .01). There was a time-dependent oxidation of the plasma GHS pool and was not affected by zinc supplementation. Conclusions: Because increased CySS level is associated with aging, oxidative stress, and age-related diseases, the apparent prevention of increased CySS by zinc supplementation warrants additional investigation.
AB - Purpose: To determine the effects of zinc supplementation on plasma thiol metabolites and their redox status in a cohort of patients with age-related macular degeneration (AMD). Design: Randomized clinical trial that evaluated the effects of high doses of zinc and antioxidants on plasma biomarkers of oxidative stress. Methods: This was an ancillary study of the Age-Related Eye Disease Study (AREDS). Subjects with AMD were randomized to one of four treatment groups: (1) antioxidants (vitamin C, 500 mg; vitamin E, 400 IU; and beta carotene, 15 mg), (2) zinc (80 mg zinc oxide, 2 mg cupric oxide), (3) antioxidants plus zinc, or (4) placebo. At 20 and 80 months after randomization, blood specimens were collected and analyzed for glutathione (GSH), oxidized glutathione (GSSG), cysteine (Cys), and cystine (CySS). Results: Although zinc supplementation had no apparent effect on plasma thiol/disulfide redox status at the first blood draw, the group of patients receiving zinc supplementation at the second blood draw had significantly less CySS compared with those not receiving zinc (54.9 vs 64.1 μM; P = .01). There was a time-dependent oxidation of the plasma GHS pool and was not affected by zinc supplementation. Conclusions: Because increased CySS level is associated with aging, oxidative stress, and age-related diseases, the apparent prevention of increased CySS by zinc supplementation warrants additional investigation.
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U2 - 10.1016/j.ajo.2006.09.056
DO - 10.1016/j.ajo.2006.09.056
M3 - Article
C2 - 17157802
AN - SCOPUS:33846337794
VL - 143
SP - 206-211.e2
JO - American Journal of Ophthalmology
JF - American Journal of Ophthalmology
SN - 0002-9394
IS - 2
ER -