Diarylheptanoid Phytoestrogens Isolated from the Medicinal Plant Curcuma comosa : Biologic Actions in Vitro and in Vivo Indicate Estrogen Receptor–Dependent Mechanisms

Abstract

BackgroundDiarylheptanoids isolated from Curcuma comosa Roxb. have been recently identified as phyto estrogens. However, the mechanism underlying their actions has not yet been identified.ObjectivesWe characterized the estrogenic activity of three active naturally occurring diarylheptanoids both in vitro and in vivo.MethodsWe 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.ResultsAll diarylheptanoids up-regulated estrogen-responsive genes in estrogen-responsive breast cancer cells (MCF-7). In HepG2 cells transfected with estrogen receptor (ER) β or different ERα functional receptor mutants and the Vit-ERE-TATA-Luc reporter gene, all diarylheptanoids induced transcription through a ligand-dependent human ERα-ERE–driven pathway, which was abolished with ICI 182,780 (ER antagonist), whereas only D2 was active with ERβ. An ERα mutant lacking the functional AF2 (activation function 2) region was not responsive to 17β-estradiol (E2) or to any of the diarylheptanoids, whereas ERα 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 E2, 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.ConclusionsThe results suggest that the D3 diarylheptanoid is an agonist for ER both in vitro and in vivo, and its biological action is ERα selective, specifically requiring AF2 function, and involves direct binding via ER as well as ERE-independent gene regulation.

Micronutrients and Oral Clefts

“…High-dose alcohol alters normal embryogenesis and is a known risk factor for oral clefts and one explanation for this association (Munger et al, 1996;DeRoo et al, 2008). Chinese herbs (e.g., curcuma comosa, angelica sinensis) in some supplements may have estrogenic effects, which could alter oral cleft risk (Winuthayanon et al, 2009;Natural Standard, 2013). Some herbs (angelica sinesis) may be prepared in or combined with alcohol (Natural Standard, 2013).…”

“…In contrast, we hypothesized that liver intake, a micronutrient-dense food, decreases the risk of having an affected child. Menstrual regulation supplements may contain alcohol or herbs with estrogenic effects that could increase oral cleft risk (Winuthayanon et al, 2009;Natural Standard, 2013). We examined other environmental risk factors, including maternal diabetes and cold, in relation to CL ± P risk.…”

Determination of the Marker Diarylheptanoid Phytoestrogens in <i>Curcuma comosa</i> Rhizomes and Selected Herbal Medicinal Products by HPLC-DAD

“…5) Our unpublished in silico-study also found that all compounds exhibited affinity to estrogen receptors and that supported the findings of previous studies in estrogen-like activity of 2 and 3. [18][19][20] Meanwhile, other diarylheptanoids isolated previously by Suksamrarn et al 5) are minor components, indicating a lower degree of potential markers. A very small amount in the plant rhizomes was also found for (6E)-1,7-diphenylhept-6-en-3-one.…”

“…[6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] Pure compounds and plant extracts of C. comosa exhibited several pharmacological activities including anti-allergic, 9) anti-inflammatory, 13) anti-melanogenesis, 8) hepatoprotective, 16) bonesparing 17) and estrogenic effects. 20) Among these pharmacological activities, the estrogen-like property of the C. comosa has evoked public interest and led to research studies for its application as a hormone replacement therapy instead of estrogen treatment.…”

“…21) Compound 2 was identified as the most potent phytoestrogenic agent. [18][19][20] In recombinant yeast system, the relative potency of estrogenic activity of 2 and 3 showed 4 and 1% respectively compared to 17β-estradiol. 5) Our unpublished in silico-study also found that all compounds exhibited affinity to estrogen receptors and that supported the findings of previous studies in estrogen-like activity of 2 and 3.…”