title: The effects of short-term oral phytoestrogen supplementation on the hypothalamic-pituitary-testicular axis in prostate cancer patients.
abstract: BACKGROUND
  Here we evaluate the effects of oral phytoestrogen supplementation on hypothalamic-pituitary-testicular (HPT) axis in CaP patients.
  
  
  METHODS
  We recruited 40 men about to undergo radical prostatectomy for CaP to receive either 240 mg of clover phytoestrogens or placebo daily for 2 weeks. Serum hormone levels were measured before and after treatment. In addition, recombinant cell bioassay was used to measure serum androgen bioactivity (ABA).
  
  
  RESULTS
  Phytoestrogen treatment increased serum LH from mean of 3.4-5.2 IU, P = 0.03. Concomitantly, non-significant trend towards decline in serum T, cfT and ABA values was noted. However, mean serum LH/T ratio was upregulated from 0.20 to 0.48 IU/nM, P = 0.004, suggesting compensated hypogonadism. During the course of treatment, serum concentration of equol correlated strongly with the concomitant decrease in ABA (r = -0.586, P = 0.022).
  
  
  CONCLUSIONS
  Phytoestrogen treatment interferes with HPT axis in CaP patients by inducing testicular resistance to LH and compensated hypogonadism.
authors.affiliation: Department of Urology, Helsinki University Central Hospital, Helsinki, Finland. antti.rannikko@hus.fi
authors.forename: Antti
authors.initials: A
authors.lastname: Rannikko
authors.forename: Anssi
authors.initials: A
authors.lastname: Petas
authors.forename: Taneli
authors.initials: T
authors.lastname: Raivio
authors.forename: Olli A
authors.initials: OA
authors.lastname: Jänne
authors.forename: Sakari
authors.initials: S
authors.lastname: Rannikko
authors.forename: Herman
authors.initials: H
authors.lastname: Adlercreutz
mesh_terms: D000284:Administration, Oral; D000368:Aged; D000728:Androgens / Q000097:blood; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D006801:Humans; D007006:Hypogonadism / Q000209:etiology / Q000503:physiopathology; D007031:Hypothalamus / Q000187:drug effects / Q000503:physiopathology*; D007986:Luteinizing Hormone / Q000097:blood / Q000502:physiology; D008297:Male; D008875:Middle Aged; D048789:Phytoestrogens / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use*; D010902:Pituitary Gland / Q000187:drug effects / Q000503:physiopathology*; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology*; D013737:Testis / Q000187:drug effects / Q000503:physiopathology*; D013739:Testosterone / Q000097:blood
chemical_list: D000728:Androgens; D048789:Phytoestrogens; D013739:Testosterone; D007986:Luteinizing Hormone