title: Diarylheptanoid phytoestrogens isolated from the medicinal plant Curcuma comosa: biologic actions in vitro and in vivo indicate estrogen receptor-dependent mechanisms.
abstract: BACKGROUND
  Diarylheptanoids isolated from Curcuma comosa Roxb. have been recently identified as phyto estrogens. However, the mechanism underlying their actions has not yet been identified.
  
  
  OBJECTIVE
  We characterized the estrogenic activity of three active naturally occurring diarylheptanoids both in vitro and in vivo.
  
  
  METHODS
  We characterized mechanisms of estrogenic action of the diarylheptanoids (3S)-1,7-diphenyl-(6E)-6-hepten-3-ol (D1), 1,7-diphenyl-(6E)-6-hepten-3-one (D2), and (3R)-1,7-diphenyl-(4E,6E)-4,6-heptadien-3-ol (D3) by using a real-time polymerase chain reaction assay, a mammalian transfection model, and a uterotrophic assay in mice.
  
  
  RESULTS
  All diarylheptanoids up-regulated estrogen-responsive genes in estrogen-responsive breast cancer cells (MCF-7). In HepG2 cells transfected with estrogen receptor (ER) beta or different ERalpha functional receptor mutants and the Vit-ERE-TATA-Luc reporter gene, all diarylheptanoids induced transcription through a ligand-dependent human ERalpha-ERE-driven pathway, which was abolished with ICI 182,780 (ER antagonist), whereas only D2 was active with ERbeta. An ERalpha mutant lacking the functional AF2 (activation function 2) region was not responsive to 17beta-estradiol (E(2)) or to any of the diarylheptanoids, whereas ERalpha lacking the AF1 domain exhibited wild-type-like activity. D3 markedly increased uterine weight and proliferation of the uterine epithelium in ovariectomized mice, whereas D1 and D2 were inactive. D3, like E(2), up-regulated lactoferrin (Ltf) gene expression. The responses to D3 in the uterus were inhibited by ICI 182,780. In addition, D3 stimulated both classical (Aqp5) and nonclassical (Cdkn1a) ER-mediated gene regulation.
  
  
  CONCLUSIONS
  The results suggest that the D3 diarylheptanoid is an agonist for ER both in vitro and in vivo, and its biological action is ERalpha selective, specifically requiring AF2 function, and involves direct binding via ER as well as ERE-independent gene regulation.
authors: Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand.
authors: Wipawee
authors: W
authors: Winuthayanon
authors: Pawinee
authors: P
authors: Piyachaturawat
authors: Apichart
authors: A
authors: Suksamrarn
authors: Mathurose
authors: M
authors: Ponglikitmongkol
authors: Yukitomo
authors: Y
authors: Arao
authors: Sylvia C
authors: SC
authors: Hewitt
authors: Kenneth S
authors: KS
authors: Korach
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D030024:Curcuma / Q000737:chemistry*; D036381:Diarylheptanoids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D004958:Estradiol / Q000031:analogs & derivatives / Q000494:pharmacology; D047628:Estrogen Receptor alpha / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology; D047629:Estrogen Receptor beta / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology; D005260:Female; D000077267:Fulvestrant; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008817:Mice, Mutant Strains; D009929:Organ Size / Q000187:drug effects; D010052:Ovariectomy; D048789:Phytoestrogens / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry*; D016133:Polymerase Chain Reaction; D011960:Receptors, Estrogen / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic / Q000187:drug effects / Q000235:genetics; D014599:Uterus / Q000166:cytology / Q000187:drug effects
chemical_list: D036381:Diarylheptanoids; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D048789:Phytoestrogens; D010936:Plant Extracts; D011960:Receptors, Estrogen; D000077267:Fulvestrant; D004958:Estradiol