title: Androgen receptor expression in the rat prostate is down-regulated by dietary phytoestrogens.
abstract: BACKGROUND
  It is well established that the growth of the prostate gland is a hormone-dependent phenomenon involving both androgenic and estrogenic control. Proliferation of prostate cells is, at least in part, under control of estrogen receptor beta (ER-beta). Phytoestrogens bind ER-beta with high affinity and therefore may have antiproliferative effects in the prostate.
  
  
  METHODS
  The prostates of male Long-Evans rats fed a diet high in phytoestrogens (Phyto-600) or very low levels of phytoestrogens (Phyto-free) were analyzed to determine the impact of dietary phytoestrogens on prostate weight and androgen receptor (AR) expression in the prostate.
  
  
  RESULTS
  Dietary phytoestrogens significantly decreased post-pubertal prostate weight gain in Phyto-600 vs Phyto-free fed males. Additionally, dietary phytoestrogens (Phyto-600) decreased AR expression in the prostate as determined by in situ hybridization.
  
  
  CONCLUSIONS
  Soy phytoestrogens, present in diet, alter prostate growth presumably by binding ER-beta and subsequently reducing AR expression within the prostate.
authors.affiliation: Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA. tlund@colostate.edu
authors.forename: Trent D
authors.initials: TD
authors.lastname: Lund
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Munson
authors.forename: Herman
authors.initials: H
authors.lastname: Adlercreutz
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Handa
authors.forename: Edwin D
authors.initials: ED
authors.lastname: Lephart
mesh_terms: D000284:Administration, Oral; D000818:Animals; D015536:Down-Regulation; D015870:Gene Expression / Q000187:drug effects; D008297:Male; D009929:Organ Size / Q000187:drug effects; D048789:Phytoestrogens / Q000008:administration & dosage / Q000032:analysis / Q000494:pharmacology*; D011467:Prostate / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D020318:Rats, Long-Evans; D011944:Receptors, Androgen / Q000235:genetics / Q000378:metabolism*
chemical_list: D048789:Phytoestrogens; D011944:Receptors, Androgen