A Novel Metabolic Pathway Regulates Urinary Tract Infections in the Bladder

一种调节膀胱尿路感染的新代谢途径

• 批准号: 10022311
• 负责人: JONATHAN M. BARASCH
• 金额: $ 23.5万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-24 至 2021-09-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10022311
• 关键词: Affect; Americas; Autoradiography; Back; Bacteria; Bacterial Genes; Biliverdine; Biological; Biological Assay; Biology; Bladder; Bladder Urothelium; Bladder mucosa; Blood Circulation; Candidate Disease Gene; Carbon Monoxide; Carrier Proteins; Cell division; Cells; Chelating Agents; Chemicals; Citrates; Communication; Complex; Critical Pathways; DNA biosynthesis; DNA metabolism; Data; Drug Metabolic Detoxication; Endocytic Vesicle; Enzymes; Epithelial; Epithelium; Erythrocytes; Escherichia coli; Event; Evolution; Gases; Gene Deletion; Gene Expression; Generations; Genes; Genetic; Growth; Hematuria; Heme; Heme Iron; Homeostasis; Human; Imaging Device; Immune; Immune response; Immunity; Infection; Intervention; Investments; Iron; Kidney; Klebsiella pneumoniae; Knockout Mice; LCN2 gene; Lead; Ligands; Liquid substance; Measures; Medical; Medicine; Membrane; Metabolic; Metabolic Pathway; Metabolism; Metals; Microscopic; Mucous Membrane; Mus; Mutation; Nature; Nutrient; Nutritional; Nutritional Immunity; Outcome; Pathway interactions; Patients; Phase; Physiology; Play; Process; Production; Protein Engineering; Proteins; Proteus mirabilis; RNA; Reporter; Research; Role; Science; Scientist; Site; Starvation; Symptoms; System; Testing; Theft; Time; Transferrin; Tropism; Universities; Ureter; Urethra; Urinary system; Urinary tract infection; Urine; Urogenital Diseases; Urology; Uropathogenic E. coli; Urothelial Cell; Urothelium; Virulence; Water; Woman; Work; apical membrane; circadian pacemaker; experimental study; falls; host-microbe interactions; innate immune mechanisms; inorganic phosphate; interest; lower urinary tract symptoms; microbial genomics; mutant; nanomolar; novel; pressure; receptor; recruit; response; tool; urinary

PROJECT 3: PROJECT ABSTRACT/SUMMARY Urinary tract infections are the most common medical problem in Urology, and one of the most pervasive medical illnesses. Patient presentation falls along a spectrum of intensive, lower urinary tract symptoms, to transient less defined discomfort and non-diagnostic urinary findings. We believe the spectrum of presenting symptoms results from different sites of colonization of bacteria and different levels of virulence at those sites. Our preliminary data indicates the bacterial tropism and virulence is directly related to the capacity of bacteria to obtain nutrients, and the most coveted substance is iron. Iron is a “precious metal” for bacteria because all metabolic processes, including energy production and cell division requires 100,000 atoms per bacteria. The urinary system is a particularly intriguing site of iron acquisition, because while the urine fluid contains only Nano-Molar iron content, the urine also contains 106 red blood cells/day, containing 109 heme iron atoms each. In this setting of iron starvation, yet potentially heme-iron abundance, bacteria can rapidly deploy tools to transfer iron from mammalian proteins, and from heme rings directly across their membrane. We propose that this setting is dominated by heme iron, and that heme transport systems take priority initially in stealing our iron. This hypothesis not only derives from analysis of bacterial gene expression, but also our study of the epithelial response to the invasion of the bladder. By creating novel tools to isolate snapshots of nascent RNA, we discovered that the urothelium and specialized cells elsewhere in the urinary system activate their own system of heme capture, heme metabolism, and iron sequestration. These activated mammalian pathways are of great interest because of the immediacy of their responses, the recruitment of novel heme transporters at the site of bacterial attack, and the production of the heme product, Carbon Monoxide, a bacteriostatic agent. In addition, these pathways not only decontaminate heme, but they are the core complex of the Circadian Clock. We are cognizant that the implications of these findings will require considerable research, but they include our finding that the apical membrane of the bladder, the urothelium, can transport heme with a novel mechanism and the realization that bacteria stimulate this process as a mechanism of innate immune defense known as nutritional immunity. As a result of these mechanisms, we found that night time and day time UTI generate different biological outcomes. In this renewal proposal for Project 3 of the Columbia University George M. O’Brien Urology Research Center we go back to basic iron biology and we carefully document heme and iron transport across the bladder, cell and bacterial responses using novel imaging tools and novel iron and CO capture tools, mouse ko’s and bacteria carrying mutations in iron pathways that are critical in mice and human infection. We work with leading microbiologists (Uhlemann), geneticists (Mendelsohn, Gharavi) and lead scientist in iron biology (Hamza). Together, our studies will demonstrate that the urothelium is a metabolically active cell layer that uses iron biology to detoxify the daily microscopic hematuria and for immune defense upon their invasion.

项目3：项目摘要/摘要 尿路感染是泌尿外科中最常见的医学问题，也是最普遍的医学之一 疾病。患者的表现沿着大量，较低的尿路症状降低，以较少 定义的不适和非诊断性尿液发现。我们相信呈现符号结果的范围 来自细菌定植的不同部位和这些部位的不同水平的病毒。我们的初步数据 表明细菌的向性和病毒与细菌获得营养的能力直接相关，并且 最令人垂涎​​的物质是铁。铁是细菌的“贵金属”，因为所有代谢过程， 包括能量生产和细胞分裂需要每个细菌100,000个原子。尿液系统是 特别有趣的铁采集部位，因为虽然尿液仅包含纳米摩尔铁含量，但 尿液还含有106个红细胞​​/天，每个尿液中含有109个血红素原子。在这种铁环境中 饥饿，但可能是血红素铁的抽象，细菌可以迅速部署工具以转移铁 哺乳动物蛋白质，以及直接从膜上的血红素环。我们建议这种设置是 以血红素铁为主，而血红素运输系统最初优先窃取我们的铁。 假设不仅源自细菌基因表达的分析，而且我们对上皮的研究 对入侵膀胱的反应。通过创建新颖的工具来隔离新生RNA的快照，我们 发现泌尿系统中其他地方的尿路上皮和专门细胞激活了自己的系统 血红素捕获，血红素代谢和铁隔离。这些激活的哺乳动物途径很棒 兴趣是由于他们的反应即时，在现场招募了新型血红素转运蛋白 细菌攻击以及血红素产物的产生，一氧化碳，抑制剂。此外， 这些途径不仅是净化血红素的，而且是昼夜节律的核心综合体。我们是 认识到这些发现的含义将需要考虑研究，但它们包括我们的发现 膀胱尿皮细胞的顶膜可以用一种新颖的机制运输血红素， 意识到细菌刺激这一过程是一种先天免疫防御的机制，称为营养 免疫。由于这些机制，我们发现夜间时间和白天uti产生了不同的 生物结果。在哥伦比亚大学项目3的续签建议中 研究中心我们回到基本的铁生物学，我们仔细记录了血红素和铁的运输 使用新型成像工具以及新颖的铁和CO捕获工具，鼠标，膀胱，细胞和细菌反应，鼠标 在铁路和人类感染中至关重要的铁途径中携带突变的KO和细菌。我们与之合作 领先的微生物学家（Uhle​​mann），遗传学家（Mendelsohn，Gharavi）和铁生物学领域的主要科学家 （hamza）。总之，我们的研究将证明尿路上皮是一种代谢活性细胞层，使用 铁生物学可在入侵时对每日微观血尿和免疫防御进行排毒。