RESPIRATORY ENDOTHELIAL INJURY BY XANTHINE OXIDASE

黄嘌呤氧化酶引起的呼吸内皮损伤

• 批准号: 2028569
• 负责人: JOHN E REPINE
• 金额: $ 32.58万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-02-10 至 2001-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2028569
• 关键词: adult respiratory distress syndrome; aldehyde /ketone oxidoreductase; enzyme activity; enzyme mechanism; free radical oxygen; gene expression; genetic mapping; genetic polymorphism; human genetic material tag; immunocytochemistry; in situ hybridization; laboratory rat; lung injury; molecular cloning; nucleic acid sequence; oxidative stress; protein structure; respiratory epithelium; xanthine oxidase

We recently cloned two human genes (AOX1 and AOX2) that encode the obligatory oxygen radical generating enzyme, aldehyde oxidase (AO) and discovered unanticipated genetic complexity in this molybdenum hydroxylase family which includes xanthine oxidase (XO). It also appears that AO could contribute to acute lung leak: First, AO, but not XO, was expressed in human lung. Second, treatment with benzoquinone or SKF-525 (AO inhibitors), but not allopurinol (an XO inhibitor), decreased lung leak in rats given interleukin-1 (IL-1)-intratracheally. Third, lung slices given AO substrate made H2O2, and more H2O2 was observed using cerium chloride staining in electron micrographs of lungs given IL-1 than in control or IL-1 and AO inhibitor treated rats Our specific hypothesis is that AO generated O2 radicals contribute to acute lung lead. Our specific aims are: 1. To characterize human and rat AOX1 and AOX2 genes by DNA sequence analysis, functional expression, antigenic mapping, and amino acid sequence analysis. 2. To determine the levels and cellular localization of AO activity and characterize AO antigen and mRNA expression in human and rat lung by in situ hybridization, immunochemistry, and histochemistry. 3. To determine the contribution of AO to the development of acute lung leak in vivo. The primary justification for the proposed approach is that: (a) The expression of AO,but not XO, in the human lung suggests a heretofore unrecognized pathway for oxygen radical generation in acute lung leak (the so called acute respiratory distress syndrome, ARDS). (b) The structures, expression and regulation of AO and XO and their genes needs to be determined to understand their specific and possibly different functional contributions to oxygen radical mediated lung leak. (c) Combined analysis of the rat and human AO genes will enable us to determine the significance of AO and to assess the potential for manipulating AO to prevent acute lung leak (ARDS) in humans.

我们最近克隆了两个人类基因（AOX 1和AOX 2），它们编码 专性氧自由基生成酶，醛氧化酶（AO） 和 在这种钼中发现了意想不到的遗传复杂性 羟化酶家族，包括黄嘌呤氧化酶（XO）。 它还 似乎 AO可能导致急性肺漏：首先，AO，而不是XO， 是 在人肺中表达。 第二，用苯醌或 SKF-525 (AO抑制剂），但不是别嘌呤醇（XO抑制剂），减少 肺 白细胞介素-1（IL-1）-经气管内给药大鼠渗漏。 第三、 肺 在AO衬底上的切片产生H2 O2，并且观察到更多的H2 O2 使用 氯化铈染色的肺部电子显微镜照片， IL-1比 在对照或IL-1和AO抑制剂处理大鼠中 我们的具体假设是，AO产生的O2自由基有助于 到 急性肺铅中毒 我们的具体目标是： 1.通过DNA鉴定人和大鼠AOX 1和AOX 2基因 序列 分析、功能表达、抗原定位和氨基酸 序列分析 2.确定AO活性的水平和细胞定位 和 表征人和大鼠肺中AO抗原和mRNA表达 采用 原位杂交、免疫化学和组织化学。 3.为了确定AO对急性脑梗死发生的作用， 肺 体内泄漏。 拟议方法的主要理由是： (a)人肺中AO而非XO的表达表明， 迄今为止未认识到氧自由基产生途径 急性 肺渗漏（所谓的急性呼吸窘迫综合征， ARDS）。 (b)AO和XO的结构、表达和调控， 他们的 基因需要被决定去理解它们的特定的， 可能 氧自由基介导肺的不同功能贡献 漏水 (c)对大鼠和人类AO基因的联合分析将使我们能够 到 确定AO的重要性，并评估 操纵AO以防止人类的急性肺渗漏（ARDS）。