In vivo and in vitro estrogenic activity of extracts from Erythrina poeppigiana (Fabaceae)

In developing countries, around 80% of the population still resorts on traditional medicine for their primary health care. (Walp.) O.F. Cook, one of these medicinal plants, was found to be particularly rich in isoflavonoids which exhibited, individually, significant estrogenic activity . The possible combined effects of these bioactive isoflavones, as they are naturally found in the crude extracts of , prompted us to assess their estrogenicity. We first tested the ability of the extracts to transactivate estrogen receptor alpha (ERα) using U2OS human osteosarcoma cells. We next investigated their effects in an uterotrophic assay, using ovariectomized rats treated with the extracts at the doses of 50, 100, 200, and 400 mg/kg BW/d orally for 3 days. Finally, we assessed their ability to relieve hot flushes, using data loggers. At the end of treatments, animals were sacrificed, and organs (mammary glands, vagina, and uteri) were collected for histo-morphometric analyses. The methanol extract significantly and dose-dependently transactivated ERα at all tested doses. All extracts induced significant increases of vaginal and uterine epithelial heights. Only the dichloromethane extract could significantly relieve hot flushes as estradiol. These results indicate that extracts have estrogen-like effects , suggesting that its active principles act in synergy when they are taken in combination in the crude extract. These findings, therefore, support the traditional use of to alleviate some menopausal problems; our previous phytochemical investigations contribute to the standardization of this phytomedicine.