DIETARY FRUCTOSE AND URINARY 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。 肾结石是一种流行的医学疾病，10%的高加索男性在一生中的某个时候会受到这种疾病的困扰，其中80%的结石主要是草酸钙。尿液中草酸排泄量是结石形成的一个重要风险因素，与饮食摄入量和内源性合成的影响差不多。草酸的内源合成是糖和氨基酸代谢的结果，主要发生在肝脏。最近，果糖摄入量被确定为结石形成的风险因素。受试者被分成五等分，并获得5.6%到15.2%的能量作为果糖。一些证据表明，果糖代谢导致草酸的合成比葡萄糖代谢的合成更多。在分离的大鼠肝细胞中，Rofe et el报告说，在糖浓度为10 mM时，果糖产生的草酸是葡萄糖的10倍。我们最近在初步的、未发表的实验中观察到，培养的人肝细胞在含有果糖的培养液中生长时，合成的草酸是含有葡萄糖的培养液中的3倍。

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. Kidney stone disease is a prevalent medical condition that afflicts 10% of Caucasian males at some point in their lifetime with 80% of these stones being predominately calcium oxalate. The amount of oxalate excreted in urine is an important risk factor for stone formation and is derived about equally from dietary intake and endogenous synthesis. The endogenous synthesis of oxalate results from the metabolism of sugars and amino acids and occurs primarily in the liver. Fructose consumption was recently identified as a risk factor for stone formation. Subjects were divided into quintiles and received between 5.6% and 15.2% of their energy as fructose. Several lines of evidence indicate that fructose metabolism results in greater synthesis of oxalate than from the metabolism of glucose. With isolated rat hepatocytes, Rofe et el reported that at sugar concentrations of 10mM, fructose produced 10 times more oxalate than glucose. We have recently observed in preliminary, unpublished experiments that cultured human hepatocytes synthesize 3 times as much oxalate when growing in media containing fructose compared with media containing glucose.