Androgen receptor expression in the rat prostate is down-regulated by dietary phytoestrogens

Reprod Biol Endocrinol. 2004 Jan 16;2:5. doi: 10.1186/1477-7827-2-5.


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.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Administration, Oral
  • Animals
  • Down-Regulation
  • Gene Expression / drug effects
  • Male
  • Organ Size / drug effects
  • Phytoestrogens / administration & dosage
  • Phytoestrogens / analysis
  • Phytoestrogens / pharmacology*
  • Prostate / chemistry
  • Prostate / drug effects
  • Prostate / metabolism*
  • Rats
  • Rats, Long-Evans
  • Receptors, Androgen / genetics
  • Receptors, Androgen / metabolism*


  • Phytoestrogens
  • Receptors, Androgen