THE EFFECT OF GENISTEIN AND ISOFLAVONE METABOLITES ON CALCIUM ABSORPTION AND

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 几种含有异黄酮类的植物产品正在作为雌激素替代疗法的替代品上市，以预防绝经后妇女的骨质疏松症。雌激素抑制骨吸收，并可能增加钙的吸收。异黄酮类药物对骨骼健康的疗效好坏参半，这可能取决于异黄酮类药物的剂量和相互作用，以及个体产生等量激素的能力。该项目将确定染料木素的剂量效应以及与其他大豆异黄酮的相互作用对绝经后妇女钙吸收和骨吸收的影响，这些妇女是马匹和非马匹的生产者。我们将使用长寿命的同位素41Ca来标记骨骼，并使用加速器质谱仪(AMS)来监测饮食的扰动。这种研究骨吸收的创新方法是一种直接测量骨吸收的方法，与骨转换和传统钙动力学的生化标记物相比，它比研究骨密度的变化更快，而且不像骨组织形态计量学那样具有侵入性。我们能够通过测量尿中41Ca排泄的变化，系统地测定不同类型和剂量的含异黄酮类植物产品在同一绝经后妇女体内抑制骨吸收的效果。作为阳性对照，异黄酮的效果将与Actonel进行比较，Actonel是一种常见的骨质疏松症治疗方法。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Several types of botanical products containing isoflavones are being marketed as an alternative to estrogen replacement therapy to prevent osteoporosis in postmenopausal women. Estrogen suppresses bone resorption and may increase calcium absorption. Efficacy of isoflavones on bone health has mixed results which may depend on the dose and interaction of isoflavones and the ability of individuals to produce equal. This project will determine the dose response of effect of genistein and the interaction with other soy isoflavones on calcium absorption and bone resorption in postmenopausal women who are equol vs. nonequol producers. We will use 41Ca, a long-lived isotope, to label the skeleton and an Accelerator Mass Spectrometry (AMS) to monitor perturbations by diet. This innovative approach to study bone resorption is a direct measure of bone resorption in contrast to biochemical markers of bone turnover and traditional calcium kinetics, rapid compared to studying changes in bone density, and not as invasive as bone histomorphometry. We are able to systematically determine the effect of various types and dosages of isoflavone-containing botanical products sequentially in the same postmenopausal women for their effectiveness in suppressing bone resorption by measuring changes in 41Ca excretion in the urine. As a positive control the effect of isoflavones will be compared to Actonel , a common osteoporosis treatment therapy.