[Estrogenic activity and its mechanism of ethanol extract from black soybean].

OBJECTIVE

To explore the estrogenic activity and its mechanism of ethanol extract from black soybean (BSE).

METHOD

The modified MCF-7 cell proliferation assay was used to evaluate the estrogenic activity of BSE. And the possible mechanisms were addressed using RT-PCR measurements in which pure estrogen receptor antagonist ICI182,780 was employed as a tool.

RESULT

The estrogenic activity of BSE at various concentrations (1-1000 microg x mL(-1)), expressed as proliferative effect (PE) relative to that of solvent control, was examined. The results indicated that, at low concentration range (10-200 microg x mL(-1)), BSE was able to induce MCF-7 cell growth with a maximum at 100 microg x mL(-1). The results of RT-PCR showed that pS2 and PR mRNA could be significantly induced by BSE in MCF-7 cells, which was relative to the concentration of BSE. Moreover, the specific estrogen receptor antagonist, ICI182,780 could block these reactions.

CONCLUSION

Ethanol extract of black soybean can stimulate the growth of MCF-7 cells and increase the expression of estrogen receptor-responsive gene, suggesting that the estrogenic effects of BSE are mediated by the estrogen receptor.