IMPACT OF DIETARY CALCIUM AND OXALATE RATIOS, AND OXALOBACTER FORMIGENES COLONIZ

膳食钙和草酸盐比例以及产草酸杆菌菌落的影响

• 批准号: 8167047
• 负责人: DEAN GEORGE ASSIMOS
• 金额: $ 12.12万
• 依托单位: WAKE FOREST UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-03-01 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8167047
• 关键词: Anaerobic Bacteria; Calcium; Calcium Oxalate; Calculi; Carbon; Carbon Dioxide; Complex; Computer Retrieval of Information on Scientific Projects Database; Diet; Dietary Calcium; Dietary Practices; Epidemiologic Studies; Equilibrium; Excretory function; Feces; Formates; Funding; Grant; Human; Individual; Institution; Intake; Intestines; Kidney Calculi; Organism; Oxalates; Oxalobacter formigenes; Population; Research; Research Personnel; Resources; Risk; Risk Factors; Source; Stream; United States National Institutes of Health; response; urinary

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. Epidemiological studies have indicated that low calcium and high oxalate intakes are risk factors for the formation of calcium oxalate kidney stones. Oxalate normally complexes with calcium in the intestine forming insoluble cyrstals which are eliminated in the fecal stream. We have shown using diets controlled in oxalate content that urinary oxalate excretion is proportional to the amount of oxalate ingested which is directly correlated with the risk of stone formation. Oxalobacter formigenes has been identified as the predominant organism degrading oxalate in human feces so colonization with this organism has been hypothesized to limit stone risk. This non-pathogenic, anaerobic bacterium uses oxalate as its main carbon source, converting it to formate and carbon dioxide. Several studies have suggested that calcium oxalate stone formers are less likely to have OxF than non-stone formers. Most dietary studies to date have used a constant ratio of calcium to oxalate in meals. This may not truly represent the normal dietary patterns in most of the U.S. population. We propose that maintaining an optimal balance between calcium and oxalate intake with each meal may limit transient episodes of increased oxalate excretion and thus reduce stone risk. We further propose that such transient increases in urinary oxalate excretion are greater in non-colonized individuals. This study will compare the response of colonized and non-colonized individuals to diets balanced and imbalanced in their calcium to oxalate ratios.

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 流行病学研究表明，低钙和高草酸盐摄入是草酸钙肾结石形成的危险因素。草酸盐通常在肠道中与钙络合，形成不溶性的钙盐，其在粪便流中被消除。我们已经表明，使用控制草酸盐含量的饮食，尿草酸盐排泄量与摄入的草酸盐量成正比，这与结石形成的风险直接相关。已确定产草酸杆菌是降解人类粪便中草酸盐的主要微生物，因此假设该微生物的定植可限制结石风险。这种非致病性厌氧细菌使用草酸盐作为其主要碳源，将其转化为甲酸盐和二氧化碳。几项研究表明，草酸钙结石患者比非结石患者患OxF的可能性更小。迄今为止，大多数饮食研究都使用膳食中钙与草酸盐的恒定比例。这可能并不能真正代表大多数美国人的正常饮食模式。我们建议，保持每餐钙和草酸盐摄入量之间的最佳平衡可能会限制草酸盐排泄增加的短暂发作，从而降低结石风险。我们进一步提出，这种短暂的增加尿草酸排泄更大的非殖民化的个人。这项研究将比较殖民和非殖民个人的反应，饮食平衡和不平衡的钙草酸盐的比例。