title: Transdermal estradiol reduces F2alpha-isoprostane levels in postmenopausal women.
abstract: OBJECTIVE
  F2alpha-isoprostanes are considered the most reliable index of in vivo oxidative stress. Given the implication of oxidative stress in the pathogenesis of atherosclerosis, we investigated the effects of hormone therapy on the plasma levels of F2alpha-isoprostanes.
  
  
  METHODS
  Sixty-one healthy postmenopausal women were treated in a randomized trial with estradiol either orally (2 mg/day, 28 women) or transdermally (50 mug/day, 33 women) for 4 weeks. Then women in each group were randomly assigned to oral progestogen, either micronized progesterone (300 mg/day) or medroxyprogesterone acetate (5 mg/day) for 2 additional weeks. Plasma samples were collected before and at the end of each treatment period, either estradiol alone or estradiol plus progestogen. F2alpha-isoprostanes were measured by a commercial enzyme immunoassay.
  
  
  RESULTS
  A significant reduction in the levels of F2alpha-isoprostanes was detected only in women receiving transdermal estradiol, alone or in combination with medroxyprogesterone acetate.
  
  
  CONCLUSIONS
  Transdermal estradiol alone or associated with medroxyprogesterone acetate decreased plasma levels of F2alpha-isoprostanes. These data elucidate additional details of the beneficial effect of estradiol on oxidative stress, a relevant mechanism in atherogenesis.
authors.affiliation: Research Foundation, Hospital Clínico Universitario de Valencia, Valencia, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Hermenegildo
authors.forename: Pilar J
authors.initials: PJ
authors.lastname: Oviedo
authors.forename: Andrés
authors.initials: A
authors.lastname: Laguna
authors.forename: Miguel Angel
authors.initials: MA
authors.lastname: García-Pérez
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Tarín
authors.forename: Antonio
authors.initials: A
authors.lastname: Cano
mesh_terms: D000279:Administration, Cutaneous; D000284:Administration, Oral; D002784:Cholesterol / Q000097:blood; D004958:Estradiol / Q000008:administration & dosage*; D015914:Estrogen Replacement Therapy; D028441:F2-Isoprostanes / Q000097:blood*; D005260:Female; D006801:Humans; D008074:Lipoproteins / Q000097:blood; D008525:Medroxyprogesterone / Q000008:administration & dosage; D008875:Middle Aged; D017698:Postmenopause / Q000097:blood*; D011372:Progestins / Q000008:administration & dosage
chemical_list: D028441:F2-Isoprostanes; D008074:Lipoproteins; D011372:Progestins; C030104:lipoprotein cholesterol; D004958:Estradiol; D002784:Cholesterol; D008525:Medroxyprogesterone