title: High dosage of ascorbic acid and alpha-tocopherol is not useful for diminishing oxidative stress and DNA damage in healthy elderly adults.
abstract: OBJECTIVE
  To determine the useful dosage of ascorbic acid and alpha-tocopherol against oxidative stress and DNA damage in the elderly.
  
  
  METHODS
  A double-blind controlled clinical assay carried out in a sample of 66 healthy subjects divided into three age-paired random groups with 22 subjects in each group. Group A received placebo and group B was administered 500 mg of ascorbic acid and 400 IU of alpha-tocopherol, whereas group C received 1,000 mg of ascorbic acid and 400 IU of alpha-tocopherol for a 6-month period. The following measurements were performed before and after the 6-month treatment period: thiobarbituric acid reactive substances (TBARS); total antioxidant status (TAS); superoxide dismutase (SOD), and glutation peroxidase (GPx) and DNA damage by comet assay.
  
  
  RESULTS
  After 6 months, group B subjects exhibited an increase in SOD and GPx enzyme levels; however, this was not statistically significant (p > 0.05). Likewise, TBARS and TAS concentrations remained unchanged (p > 0.05). In addition, in group C the decrease in TBARS and increase in SOD, GPx, and TAS were not statistically significant (p > 0.05). Similarly, average DNA migration showed no significant differences with high-dosage ascorbic acid and alpha-tocopherol.
  
  
  CONCLUSIONS
  These findings suggest that administration of 1,000 mg of ascorbic acid plus 400 IU of alpha-tocopherol for 6 months is not useful for diminishing oxidative stress and DNA damage in healthy elderly adults.
authors.affiliation: Unidad de Investigación en Gerontología, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, Mexico City, Mexico.
authors.forename: Raquel
authors.initials: R
authors.lastname: Retana-Ugalde
authors.forename: Esther
authors.initials: E
authors.lastname: Casanueva
authors.forename: Mario
authors.initials: M
authors.lastname: Altamirano-Lozano
authors.forename: Cristina
authors.initials: C
authors.lastname: González-Torres
authors.forename: Víctor Manuel
authors.initials: VM
authors.lastname: Mendoza-Núñez
mesh_terms: D000368:Aged; D000975:Antioxidants / Q000008:administration & dosage / Q000032:analysis / Q000627:therapeutic use*; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000097:blood / Q000627:therapeutic use*; D004249:DNA Damage / Q000187:drug effects*; D004311:Double-Blind Method; D004912:Erythrocytes / Q000201:enzymology; D005260:Female; D005979:Glutathione Peroxidase / Q000097:blood; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D008800:Mexico; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects*; D013482:Superoxide Dismutase / Q000097:blood; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D017211:Treatment Failure; D014505:Urban Population; D014810:Vitamin E / Q000097:blood; D024502:alpha-Tocopherol / Q000008:administration & dosage / Q000627:therapeutic use*
chemical_list: D000975:Antioxidants; D017392:Thiobarbituric Acid Reactive Substances; D014810:Vitamin E; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D024502:alpha-Tocopherol; D001205:Ascorbic Acid