Estrogenic/antiestrogenic activities of a Epimedium koreanum extract and its major components: in vitro and in vivo studies

• Published in: Food and chemical toxicology Vol. 50; no. 8; pp. 2751 - 2759
• Main Authors: Kang, Hyun Ku, Choi, Yun-Ho, Kwon, Hyosuk, Lee, Sang-Bum, Kim, Dong-Hyun, Sung, Chung Ki, Park, Young In, Dong, Mi-Sook
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.08.2012; Elsevier
• Subjects: Animals; Biological and medical sciences; Cell Line; Epimedium; Epimedium - chemistry; Epimedium koreanum; Estrogen Receptor Modulators - pharmacology; estrogen receptors; estrogenic properties; Estrogenic/antiestrogenic activity; Estrogens - pharmacology; Female; gene expression regulation; glycosides; Humans; Icariin; Icaritin; In Vitro Techniques; in vivo studies; Medical sciences; medicinal plants; ovariectomy; plant estrogens; Plant Extracts - pharmacology; quercetin; Rats; Rats, Sprague-Dawley; Reporter gene assay; reporter genes; Toxicology; Uterotrophic assay; China; Korean Peninsula; Icariin; Estrogenic/antiestrogenic activity; ICA; Icaritin; Uterotrophic assay; ER; REA; OVX; Epimedium koreanum; Reporter gene assay; ERE; Epi ext; ICT; Mimetic hormone; Antiestrogen; Extract; Endocrine disruptor; Experimental study; In vitro; Biological activity; In vivo; Reporter gene; Uterus
• ISSN: 0278-6915; 1873-6351
• DOI: 10.1016/j.fct.2012.05.017

► ICT and quercetin exhibited in vitro ER mediated estrogenic activity with a more potent interaction with ERβ. ► Prenylflavonoid glycosides did not show any in vitro estrogenic activities. ► The potency of in vitro estrogenic activity was in the order of ICT>Epi ext>ICA. ► ICA had the strongest estrogenic activity in ovariectomized rats. The estrogenic and antiestrogenic activities of Epimedii Herba, which is a traditional medicinal herb used in Korea and China were investigated in this study. The in vitro estrogen receptor (ER) mediated estrogenic/antiestrogenic activities of an Epimedii Herba extract (Epi ext) and its major components were determined using an estrogen responsive element driven reporter gene assay in MCF-7/ERE and HEK293T cells. The Epi ext exhibited ERα- and ERβ-mediated estrogenic activity with an EC50 of 5.0 and 17.8μM in HEK293T cells, respectively. Prenylflavonoid glycosides such as icariin (ICA), epimedin A, B, and C did not show any in vitro estrogenic or antiestrogenic activities. Icaritin (ICT) and quercetin exhibited in vitro ER mediated estrogenic activity with a more potent interaction with ERβ. In vivo estrogenic activities of the Epi ext, ICA and ICT were compared using an uterotrophic assay. Although the potency of in vitro estrogenic activity was in the order of ICT>Epi ext>ICA, ICA had the strongest estrogenic activity and next ICT in ovariectomized rats. These results collectively suggest that phytoestrogens possess both estrogenic and antiestrogenic activity, and that the differential expression of these two compounds with opposing activities is dependent on the physiological environment in terms of estrogen level, which may be the case in humans.