title: Age-related sex differences in glutathione peroxidase and oxidative DNA damage in a healthy Mexican population.
abstract: OBJECTIVE
  It has been proposed that women have an estrogen activity-linked biological antioxidant advantage and that this advantage is lost in the postmenopausal stage. The latter remains controversial. Our aim was to determine age-related sex differences in oxidative stress and oxidative DNA damage in a healthy Mexican population.
  
  
  METHODS
  A cross-sectional and comparative study was carried out in a convenience sample of 162 healthy subjects aged as follows: (1) 25-44 years (n = 35 women and 38 men), (2) 45-64 years (n = 41 women and 27 men), and (3) >or=65 years (n = 13 women and 8 men). We measured plasma lipoperoxides (LPO), superoxide dismutase (SOD), glutathione peroxidase (GPx), and DNA damage by comet assay.
  
  
  RESULTS
  We found greater activity of GPx in women than in men according to age increase (p < 0.05). This activity is maintained in old age in women. In contrast, men exhibited a significant diminution in GPx according to age increase. Similarly, we observed a greater percentage of cells without oxidative DNA damage in women in the 45-64-years age group and in the group of women aged >or=65 years.
  
  
  CONCLUSIONS
  Our findings suggest that women have a more efficient antioxidant activity than men, which has been linked with the greater longevity observed in women.
authors.affiliation: Unidad de Investigación en Gerontología, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, México DF, México.
authors.forename: Víctor Manuel
authors.initials: VM
authors.lastname: Mendoza-Núñez
authors.forename: Ada
authors.initials: A
authors.lastname: Beristain-Pérez
authors.forename: Silvia Patricia
authors.initials: SP
authors.lastname: Pérez-Vera
authors.forename: Mario A
authors.initials: MA
authors.lastname: Altamirano-Lozano
mesh_terms: D000328:Adult; D000367:Age Factors; D020552:Comet Assay; D003430:Cross-Sectional Studies; D004249:DNA Damage; D005260:Female; D005979:Glutathione Peroxidase / Q000097:blood*; D006801:Humans; D008054:Lipid Peroxides / Q000097:blood*; D008297:Male; D008800:Mexico; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology*; D012737:Sex Factors; D012907:Smoking; D013482:Superoxide Dismutase / Q000097:blood*; D011795:Surveys and Questionnaires; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D055815:Young Adult
chemical_list: D008054:Lipid Peroxides; D017392:Thiobarbituric Acid Reactive Substances; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase