2,3-cis-2R,3R-(−)-epiafzelechin-3-O-p-coumarate, a novel flavan-3-ol isolated from Fallopia convolvulus seed, is an estrogen receptor agonist in human cell lines

BMC Complementary and Alternative Medicine

Research Article

Dirk M Holstege¹  James R Millam²  Elisa G Gutierrez³  Michael S Denison⁴  Anatoly A Soshilov⁴  Jennifer C Brennan⁴  Prokopios Magiatis⁵  Jerry L Dallas⁶ 

[1] Agricultural and Natural Resources Analytical Laboratory, University of California, One Shields Avenue, 95616, Davis, CA, USA;Department of Animal Science, University of California, One Shields Avenue, 95616, Davis, CA, USA;Department of Chemistry, One Shields Avenue, 95616, Davis, CA, USA;Department of Environmental Toxicology, University of California, One Shields Avenue, 95616, Davis, CA, USA;Department of Pharmacognosy and Natural Products Chemistry, Faculty of Pharmacy, University of Athens, Panepistimioupolis Zografou, 15 771, Athens, Greece;Nuclear Magnetic Resonance (NMR) Facility Office, University of California, One Shields Avenue, 95616, Davis, CA, USA;

关键词: Fallopia convolvulus;    Phytoestrogens;    Bioassay-directed fractionation;    HPLC/MS/NMR;    O;    Emodin;    Transfection;    Estrogen receptor;    Relative estrogenic potency;   

DOI  :  10.1186/1472-6882-13-133

 received in 2012-07-05, accepted in 2013-05-22,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundThe plant genus Fallopia is well-known in Chinese traditional medicine and includes many species that contain bioactive compounds, namely phytoestrogens. Consumption of phytoestrogens may be linked to decreased incidence of breast and prostate cancers therefore discovery of novel phytoestrogens and novel sources of phytoestrogens is of interest. Although phytoestrogen content has been analyzed in the rhizomes of various Fallopia sp., seeds of a Fallopia sp. have never been examined for phytoestrogen presence.MethodsAnalytical chemistry techniques were used with guidance from an in vitro estrogen receptor bioassay (a stably transfected human ovarian carcinoma cell line) to isolate and identify estrogenic components from seeds of Fallopia convolvulus. A transiently transfected human breast carcinoma cell line was used to characterize the biological activity of the isolated compounds on estrogen receptors (ER) α and β.ResultsTwo compounds, emodin and the novel flavan-3-ol, (−)-epiafzelechin-3-O-p-coumarate (rhodoeosein), were identified to be responsible for estrogenic activity of F. convolvulus seed extract. Absolute stereochemistry of rhodoeosein was determined by 1 and 2D NMR, optical rotation and circular dichroism. Emodin was identified by HPLC/DAD, LC/MS/MS, and FT/ICR-MS. When characterizing the ER specificity in biological activity of rhodoeosein and emodin, rhodoeosein was able to exhibit a four-fold greater relative estrogenic potency (REP) in breast cells transiently-transfected with ERβ as compared to those transfected with ERα, and emodin exhibited a six-fold greater REP in ERβ-transfected breast cells. Cell type-specific differences were observed with rhodoeosein but not emodin; rhodoeosein produced superinduction of reporter gene activity in the human ovarian cell line (> 400% of maximum estradiol [E2] induction) but not in the breast cell line.ConclusionThis study is the first to characterize the novel flavan-3-ol compound, rhodoeosein, and its ability to induce estrogenic activity in human cell lines. Rhodoeosein and emodin may have potential therapeutic applications as natural products activating ERβ, and further characterization of rhodoeosein is necessary to evaluate its selectivity as a cell type-specific ER agonist.

【 授权许可】

CC BY   
© Brennan et al.; licensee BioMed Central Ltd. 2013