title: Serum cholesterol efflux potential in postmenopausal women treated with isolated isoflavones.
abstract: OBJECTIVE
  Based on the low cardiovascular risk in Asian populations, phytoestrogens are believed to provide vascular benefits. To elucidate the mechanisms behind the possible cardiovascular effects of phytoestrogens, we evaluated reverse cholesterol transport by assessing the capacity of serum to promote cholesterol efflux in postmenopausal women treated with isolated isoflavones.
  
  
  METHODS
  Thirty postmenopausal women were treated in a randomized, placebo-controlled, crossover trial with isoflavones or placebo for 3 months interrupted by a 2-month washout period. Serum samples were collected before and after each treatment period, and the cholesterol efflux potential was investigated by using H-cholesterol--labeled Fu5AH cells in culture.
  
  
  RESULTS
  Serum promoted 20.2% +/- 3.0% and 19.9% +/- 3.4% (mean +/- SD) cholesterol efflux after isoflavonoid treatment and after placebo treatment, respectively. Thus, the isoflavone treatment did not affect serum cholesterol efflux. We also studied separately women who produced high concentrations of the isoflavone metabolite equol into serum because some studies suggest that equol could exert favorable vascular effects. However, there was no difference in serum cholesterol efflux capacity between the equol producers (n = 15) and non-equol producers (n = 15).
  
  
  CONCLUSIONS
  In conclusion, isoflavone treatment did not affect serum cholesterol efflux potential in postmenopausal women. Based on our findings, isolated isoflavones do not provide vascular benefits by improving cholesterol efflux.
authors.affiliation: Department of Obstetrics and Gynecology, Helsinki University Central Hospital, Finland.
authors.forename: Riina M
authors.initials: RM
authors.lastname: Törmälä
authors.forename: Eini
authors.initials: E
authors.lastname: Nikander
authors.forename: Aila
authors.initials: A
authors.lastname: Tiitinen
authors.forename: Mervi
authors.initials: M
authors.lastname: Väisänen-Tommiska
authors.forename: Olavi
authors.initials: O
authors.lastname: Ylikorkala
authors.forename: Tomi S
authors.initials: TS
authors.lastname: Mikkola
mesh_terms: D000328:Adult; D000368:Aged; D002460:Cell Line; D002784:Cholesterol / Q000097:blood*; D004311:Double-Blind Method; D060754:Equol; D005260:Female; D019833:Genistein / Q000097:blood; D006801:Humans; D007529:Isoflavones / Q000097:blood / Q000627:therapeutic use*; D008055:Lipids / Q000097:blood; D008074:Lipoproteins / Q000097:blood; D008875:Middle Aged; D010919:Placebos; D017698:Postmenopause / Q000097:blood*; D014316:Tritium
chemical_list: C007610:4',7-dihydroxy-3,4-dihydroisoflavone; D007529:Isoflavones; D008055:Lipids; D008074:Lipoproteins; D010919:Placebos; D014316:Tritium; D060754:Equol; C004742:daidzein; D002784:Cholesterol; D019833:Genistein