title: The short-term effects of antioxidant and zinc supplements on oxidative stress biomarker levels in plasma: a pilot investigation.
abstract: OBJECTIVE
  To determine if short-term Age-Related Eye Disease Study (AREDS) antioxidant and zinc supplementation affects biomarkers of oxidative stress, possibly serving as a predictor of their efficacy.
  
  
  METHODS
  Prospective interventional case series.
  
  
  METHODS
  Nineteen subjects, 12 with intermediate or advanced age-related macular degeneration (AMD) (AREDS categories 3 or 4) and 7 non-AMD controls, were admitted to the Vanderbilt General Clinical Research Center and placed on a controlled diet for 7 days. Antioxidant and zinc supplements were stopped 2 weeks prior to study enrollment. Dietary supplementation with 500 mg vitamin C, 400 IU vitamin E, 15 mg β-carotene, 80 mg zinc oxide, and 2 mg cupric oxide per day was instituted on study day 2. Blood was drawn on study days 2 and 7, and plasma concentrations of cysteine (Cys), cystine (CySS), glutathione (GSH), isoprostane (IsoP), and isofuran (IsoF) were determined.
  
  
  RESULTS
  Short-term AREDS supplementation significantly lowered mean plasma levels of CySS in participants on a regulated diet (P = .034). No significant differences were observed for Cys, GSH, IsoP, or IsoF. There were no significant differences between AMD patients and controls.
  
  
  CONCLUSIONS
  This pilot interventional study shows that a 5-day course of antioxidant and zinc supplements can modify plasma levels of CySS, suggesting that this oxidative stress biomarker could help predict how likely an individual is to benefit from AREDS supplementation. Further, CySS may be useful for the evaluation of new AMD therapies, particularly those hypothesized to affect redox status.
authors.affiliation: Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN 37232-8808, USA.
authors.forename: Milam A
authors.initials: MA
authors.lastname: Brantley
authors.forename: Melissa P
authors.initials: MP
authors.lastname: Osborn
authors.forename: Barton J
authors.initials: BJ
authors.lastname: Sanders
authors.forename: Kasra A
authors.initials: KA
authors.lastname: Rezaei
authors.forename: Pengcheng
authors.initials: P
authors.lastname: Lu
authors.forename: Chun
authors.initials: C
authors.lastname: Li
authors.forename: Ginger L
authors.initials: GL
authors.lastname: Milne
authors.forename: Jiyang
authors.initials: J
authors.lastname: Cai
authors.forename: Paul
authors.initials: P
authors.lastname: Sternberg
mesh_terms: D000368:Aged; D000975:Antioxidants / Q000008:administration & dosage*; D001205:Ascorbic Acid / Q000008:administration & dosage; D015415:Biomarkers / Q000097:blood*; D003300:Copper / Q000008:administration & dosage; D003545:Cysteine / Q000097:blood*; D003553:Cystine / Q000097:blood; D019587:Dietary Supplements; D005260:Female; D005663:Furans / Q000097:blood; D005978:Glutathione / Q000097:blood; D006801:Humans; D028421:Isoprostanes / Q000097:blood; D008268:Macular Degeneration / Q000097:blood / Q000188:drug therapy*; D008297:Male; D018384:Oxidative Stress; D010865:Pilot Projects; D011446:Prospective Studies; D014810:Vitamin E / Q000008:administration & dosage; D015034:Zinc Oxide / Q000008:administration & dosage*; D019207:beta Carotene / Q000008:administration & dosage
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D005663:Furans; D028421:Isoprostanes; D019207:beta Carotene; D014810:Vitamin E; D003553:Cystine; D003300:Copper; D005978:Glutathione; D003545:Cysteine; D001205:Ascorbic Acid; D015034:Zinc Oxide; C030973:cupric oxide