The physiological actions of isoflavone phytoestrogens.

Isoflavones are a subgroup of phytoestrogens, natural plant substances with structure similar to 17-beta-estradiol and capable of binding to estrogen receptors (ERs). Isoflavones possess higher affinity to ERbeta than to ERalpha and may have a potency to activate both genomic and non-genomic estrogen signaling pathways. In addition, isoflavones interact with the metabolism of steroid hormones. Therefore, the actions of isoflavones are rather complex and may be related to large number of factors, which are not satisfactorily identified yet. Recently, isoflavones have come into focus of interest due to several reports about their positive effect on human health, in particular prevention of hormone-dependent cancers, cardiovascular diseases, osteoporosis, adverse menopausal manifestations and age-related cognitive decline. Isoflavones may bring new insights into the mechanisms of physiological regulations and increase the possibilities of medical interventions.