Daidzein estrogenic activity

Besides the affinity of genistein, daidzein, biochanin A, formononetin, coumestrol and some other flavonoids, there is little information regarding other isoflavones, of which more than 300 have been reported to exist [6], One such example is glycitein, whose estrogenic activity has been reported in one study. The data indicated that glycitein, when fed to female mice at 3 mg/day for 4 days, produced weak estrogenic activity comparable to that of other isoflavones, but much lower than that produced by diethylstilbestrol and 17[3-estradiol [54],... 

Isoflavones Genistein, daidzein, formononetin (D 22.3.3) Estrogenic activity in mammals and birds... 

A recent study found that mycorrhizal red clover showed impaired levels of isoflavones with estrogenic activity, such as biochanin A, formononetin, genistein, or daidzein [150], and natural plant metabolites called phytoestrogens, which are believed to play an important preventive role in osteoporosis, menopausal... 

Isoflavonoids show fungicidal and bactericidal effects. They play an important role as constitutive constituents and also as phytoalexins. From the pharmacological point of view estrogenic activity of isoflavones such as genistein and daidzein is of increasing relevance (Harbome and Williams 2000). Rotenoids, especially rotenone, are potent insecticides. 

Coumestrol, genistein, biochanin A, and daidzein have estrogenic activities on ruminants. Stndies have also demonstrated that coumestrol when fed to pullets increases the age of matnrity and depresses egg... 

ZHANG Y, SONG T T, CUNNICK J E, MURPHY p A and HENDRICH s (1999a) Daidzein and genistein glucuronides in vitro are weakly estrogenic and activate human natural killer cells in nutritionally relevant concentrations. /iVMr 129 (2) 399-405. 

Structural similarity of the isoflavones to estrogen has been responsible for claims that they are natural alternatives to hormone replacement therapy (HRT). Soy isoflavones are not usually present in humans, unless caused by acute or chronic administration of soy products in the diet. If not in the diet, supplementation is required. One synthetic isoflavone, ipriflavone, has been shown to increase bone mass in postmenopausal women. The soy isoflavone daidzein makes up 10%o of the metabolites of ipriflavone, and it appears to be one of the metabolites that inhibit osteoclast activity in vitro. A number of studies have been reported on the effects of soy protein and genistein on bone density in rats, and it appears that it is the isoflavones that are responsible for the beneficial effects. Positive data from studies with cultured bone cells support a... 

Zhang, Y., Song, T.T., Cunnick, J.E., and Murphy, P.A. 1999. Daidzein and genistein glucu-ronides in vitro are weakly estrogenic and activate human natural killer cells at nutritionally relevent concentrations. J. Nutr. 129 399 405. 

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