ORAL ADMINISTRATION OF SOY ISOFLAVONES AND DETERMINATION OF SERUM ISOFLAVONE LEVELS IN SPRAGUE-DAWLEY RATS

摘要

Soybean isoflavones have been shown to have various physiological effects that may be relevant to human health. Daidzein, genistein and glycitein are isoflavone aglycons in soybeans, and occur predominately in a Β-glucoside form in plants and foodstuffs (Kudou el al., 1991). One of the main products of daidzein metabolism in humans appears to be equol (Kerry el at, 1993). Genistein, daidzein, glycitein and equol have estrogenic activity, which are termed phytoestrogen (Setchell el al., 1998), and have been found to influence in vivo estrogenic metabolism (Cassidy el al., 1994; Scmitt el al., 2001). Epidemiological reports have shown that consumption of soy isoflavones decrease the risk of breast cancer, lung cancer, leukemia, and prostate cancer (Messina et al., 1994). These results suggest that soybean isoflavones in foodstuffs are absorbed in our body to exert a biological effect. Thus, it is important to determine the amount of these compounds in biological samples such as serum and various tissues in order to clarify the expression and biological action mecanism.