Assessment of estrogenic activity of flavonoids from Mediterranean plants using an in vitro short-term test

• Published in: Phytomedicine (Stuttgart) 2005, Vol.12 (1), p.143-147
• Main Authors: Garritano, S., Pinto, B., Giachi, I., Pistelli, L., Reali, D.
• Format: Article
• Language: English
• Subjects: beta-galactosidase; bioassays; Dosage and administration; Estradiol - pharmacology; estrogen receptor; Estrogen Receptor alpha - drug effects; estrogen responsive element; estrogenic properties; flavones; flavonoids; Flavonoids - administration & dosage; Flavonoids - pharmacology; Flavonoids - therapeutic use; gene expression; Genista; Genista ephedroides; Genista morisii; hormone receptors; Humans; Isoflavones; medicinal plants; Medicine, Traditional; Mediterranean Region; Phytoestrogens; Phytoestrogens - administration & dosage; Phytoestrogens - pharmacology; Phytoestrogens - therapeutic use; Phytotherapy; plant estrogens; Plant Extracts - administration & dosage; Plant Extracts - pharmacology; Plant Extracts - therapeutic use; promoter regions; Properties; Reporter gene assay; reporter genes; Saccharomyces cerevisiae; Saccharomyces cerevisiae - genetics; screening; Transcription, Genetic - drug effects; Yeast strain RMY 326 ER-ERE
• ISSN: 0944-7113; 1618-095X
• DOI: 10.1016/j.phymed.2004.01.004

Six isoflavones, daidzein (4′,7,-dihydroxyisoflavone), genistein (4′,5,7-trihydroxyisoflavone), genistin (genistein 7- O- β- D-glucopyranoside), isoprunetin (4′,7-dihydroxy, 5-metoxyisoflavone), isoprunetin 7- O- β- D-glucopyranoside, isoprunetin 4′,7-di- O- β- D-glucopyranoside and four flavones, luteolin (3′,4′,5,7-tetrahydroxyflavone), luteolin 7- O- β- D-glucopyranoside, luteolin 4′- O- β- D-glucopyranoside, licoflavone C (4′,5,7-trihydroxy,8-isoprenylflavone) were purified from Mediterranean plants ( Genista morisii and Genista ephedroides) and their estrogenic activity was assessed by a yeast reporter gene assay ( Saccharomyces cerevisiae RMY326 ER-ERE). Licoflavone C showed a powerful estrogenic activity at 10 −7 M (0.0338 μg/ml) and it was 47.45% than 10 −8 M 17 β-estradiol (0.00272 μg/ml). The estrogenicity of this flavone was found to be comparable to the activity showed by genistein at 10 −6 M (0.27 μg/ml). This study points out that a glucose substituent in flavones and isoflavones modulates the hormone-like activity in a different way. Isoflavone aglycones showed a more estrogenic activity than the corresponding glucosides. Conversely, the glucosidation made estrogenic the flavone luteolin and the position of substitution differently influenced the estrogenic activity of compounds.