COLONIZATION WITH OXALOBACTER FORMIGENES AND OXALATE EXCRETION

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。 饮食中的草酸在肾结石的形成中起着关键作用。初步证据表明，肠道有机体草酸杆菌对膳食草酸的降解可能会限制尿液中草酸的吸收和排泄。为了确定草酸杆菌的作用，我们将研究正常受试者对饮食草酸和钙变化的反应，这些受试者无论是被定植还是未被定植。这些研究将使用GCRC的新陈代谢厨房来准备控制草酸、钙和其他营养素含量的饮食。受试者将食用3种水平的草酸和3种水平的钙。每种饮食将持续7天，受试者将收集所有通过分析的尿液和粪便。这些样本将进行草酸杆菌、草酸盐和钙的分析。这些结果将阐明草酸杆菌定植在肾结石形成中的潜在重要性，并确定饮食中草酸和钙如何调节草酸杆菌在肠道中的定植水平。

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. Dietary oxalate plays a critical role in kidney stone formation. Preliminary evidence suggests that degradation of dietary oxalate by the gut organism, Oxalobacter formigenes, may limit the amount of oxalate absorbed and excreted in urine. To identify the role of Oxalobacter formigenes we will examine the response of normal subjects, who are either colonized or not colonized with the bacterium, to changes in dietary oxalate and calcium. These studies will be performed using the metabolic kitchen of the GCRC to prepare diets that are controlled in their contents of oxalate, calcium and other nutrients. Subjects will consume diets with 3 levels of oxalate and 3 levels of calcium. Each diet will be consumed for 7 days and subjects will collect all urine and feces passed for analysis. These samples will be analyzed for Oxalobacter, oxalate and calcium. The results will illustrate the potential importance of Oxalobacter colonization in kidney stone formation and identify how dietary oxalate and calcium regulate colonization levels of Oxalobacter in the gut.