Soy phytoestrogens genistein

Kim H, Xu J, Su Y et al. Actions of the soy phytoestrogen genistein in models of human chronic disease potential involvement of transforming growth factor p. Biochem. Soc. Trans. 29, 216-222, 2001. 

Dang, Z.-C. V. Audinot S.E. Papapoulos J.A. Boutin C.W.G.M. Lowik. Peroxisome proliferator-activated receptor gamma (ppargamma) as a molecular target for the soy phytoestrogen genistein. 

De Lemos ML. Effects of soy phytoestrogens genistein and daidzein on breast cancer growth. Ann Pharmacother 2001 35 1118-1121. 

The mayor soy phytoestrogens are genistein and daidzein, and genistein in particular has been used in animal experiments for inhibition of growth of a number of cancer cell lines. It has been shown to inhibit breast and skin cancer, and inhibit the formation of... 

Soy phytoestrogens, especially isoflavone derivatives daid-zein and genistein, are nutritional factors that, among many other effects, may affect iodine utilization. 

Si H, Liu D (2008) Genistein, a soy phytoestrogen, upregulates the expression of hiunan endothelial nitric oxide synthase and lowers blood pressure in spontaneously hypertensive rats. J Nutr 138 297-304... 

The mucosa of the GIT represents an interface between the external and internal environments. The expansive surface area is necessary for the efficient hydrolysis of foodstuffs and the absorption of energy and nutrients. The mucosa also influences the systemic availability of non-nutrient compounds in the diet, both beneficial and detrimental. Digestion and absorption of glucosinolates are critical determinants of health benefits (see Chapter 4) Similarly, the bioavailability and health benefits of phytoestrogens, such as genistein (see Chapters 5 and 10) are at least partly dependent on the carrier-mediated processes of absorption associated with the GIT (Oitate et al, 2001). Moreover, the metabolic activities of the mucosa can influence the systemic concentrations and forms of dietary phytochemicals, as exemplified by research with soy isoflavones (Andlauer et al., 2000). 

An inverse correlation between thyroid cancer risk and phytoestrogens was recently proposed as a result of a multi-ethnic population-based case control study conducted in the San Francisco Bay Area (Hom-Ross et al., 2002). In this study, dietary habits and phytoestrogen consumption were assessed by a food-frequency questionnaire and by a nutrient database. The outcome of the study was that soy-based foods and alfalfa sprouts were associated with a reduction of thyroid cancer risk, whereas a Western diet did not influence cancer risk. No difference was observed between American and Asian women or between pre- and postmenopausal women. Furthermore, among the few compounds examined, the isoflavones genistein and daidzein and the lignan secoisolariciresinol were the phytoestrogens most frequently associated with risk reduction (Horn-Ross et al., 2002). 

In 1987, Ken Setchell first described the method for the isolation of phytoestrogen in soy (Setchell et al., 1987). The phytoestrogens daidzein, genistein, coumestrol, formononetin, and biochanin-A were separated on a Cl8 reversed-phase column (Hypersil ODS) with methanol-0.1 M ammonium acetate buffer, pH 4.6 (60 40 v/v), as eluent. The retention and resolution were affected by buffer concentrations, pH type, and proportion of organic solvent in the mobile phase. Detection in the low picograms range was achieved with an electrochemical detector, and the compounds were positively identified by HPLC-thermospray mass spectrometry. 

The isoflavones found in soy bean extracts, such as genistein and daidzein, that are phytoestrogens, are also able to enhance HA deposition.281,282 Their estrogen-like structures may account for their ability to enhance HA deposition. 

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