Schmitt Elmar, Metzler Manfred, Jonas Rene, Dekant Wolfgang, Stopper Helga
Institute of Pharmacology and Toxicology, University of Wuerzburg, Versbacher Strasse 9, D-97078 Wuerzburg, Germany.
Mutat Res. 2003 Dec 9;542(1-2):43-8. doi: 10.1016/j.mrgentox.2003.08.003.
Products containing phytoestrogens are increasingly promoted as the "natural" alternative to estrogen replacement therapy. In the present study, we have used the in vitro micronucleus assay in L5178Y mouse lymphoma cells to investigate the genotoxic potential of the isoflavone daidzein, and of four daidzein metabolites known to be formed in humans. Whereas no induction of micronuclei was observed with daidzein up to the limit of solubility (100 microM), all four daidzein metabolites, i.e. equol (2.3-fold induction at 100 microM), O-desmethylangolensin (6.2-fold induction at 10 microM), 4',6,7-isoflavone (6.7-fold induction at 100 microM) and 3',4',7-isoflavone (8.2-fold induction at 100 microM) induced micronuclei in a concentration-dependent manner. Thus, both reductive and oxidative metabolites of the soy isoflavone daidzein exhibit genotoxic potential in vitro.
含有植物雌激素的产品越来越多地被宣传为雌激素替代疗法的“天然”替代品。在本研究中，我们使用L5178Y小鼠淋巴瘤细胞的体外微核试验来研究异黄酮大豆苷元及其已知在人体内形成的四种代谢产物的遗传毒性潜力。在大豆苷元达到溶解度极限（100微摩尔）之前未观察到微核诱导现象，而所有四种大豆苷元代谢产物，即雌马酚（100微摩尔时诱导2.3倍）、O-去甲基安哥拉紫檀素（10微摩尔时诱导6.2倍）、4',6,7-异黄酮（100微摩尔时诱导6.7倍）和3',4',7-异黄酮（100微摩尔时诱导8.2倍）均以浓度依赖方式诱导微核。因此，大豆异黄酮大豆苷元的还原和氧化代谢产物在体外均表现出遗传毒性潜力。
