Androgen receptor expression in the rat prostate is down-regulated by dietary phytoestrogens.
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.
Lund
Trent D
TD
Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA. tlund@colostate.edu
Munson
Daniel J
DJ
Adlercreutz
Herman
H
Handa
Robert J
RJ
Lephart
Edwin D
ED
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*
D048789:Phytoestrogens; D011944:Receptors, Androgen