Redox Activity of the Pulmonary Endothelial Surface

肺内皮表面的氧化还原活性

• 批准号: 6924083
• 负责人: MARILYN P MERKER
• 金额: $ 22.05万
• 依托单位: MEDICAL COLLEGE OF WISCONSIN
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-08-20 至 2009-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6924083
• 关键词: NAD(P)H dehydrogenase; antioxidants; blood lipoprotein metabolism; cell membrane; electron transport; enzyme activity; enzyme induction /repression; enzyme model; human tissue; hydroquinones; membrane proteins; oxidation reduction reaction; oxidative stress; paraquat; pulmonary circulation; pyridine nucleotide; quinones; tissue /cell culture; toxin metabolism; ubiquinone; vascular endothelium

DESCRIPTION (provided by applicant): The pulmonary endothelium influences the redox status of blood borne redox active endogenous, pharmacological, toxicological and dietary compounds. It does so by acting as a large chemical reactor surface comprised of cell surface and intracellular redox enzymes situated between the venous and arterial circulations. The impact of the endothelium on the redox status of these compounds affects their bioactivity, including pro-or anti-oxidant effects, tissue permeation, and chemical reactivity. Quinones represent 1 important class of redox-active compounds with a range of physiological, pharmacological, and toxicological activities. The hypothesis underlying this proposal is that redox metabolism of quinones by pulmonary endothelial cells determines the quinone reduction products, and their bioactivity, within the lung and endothelial cells, the plasma, and downstream vessels and organ systems. The goal of the proposed research is to identify and quantify the factors, with regard to properties of both the cells and quinones, that determine the fate of a given quinone that comes in contact with the pulmonary endothelium. The specific aims are to: 1. Identify and quantify the pulmonary endothelial quinone reductase and hydroquinone oxidase mediated reactions contributing to the fate of a series of quinones with varying physical and chemical properties: 2. Determine the dependence of the activities of quinone reductases contributing to the fate of a given quinone on the pulmonary endothelial redox status: 3. Determine the influence of adaptation of the pulmonary endothelium to hyperoxia on the redox processes contributing to quinone fate. To achieve these aims, the general approaches include: measuring the kinetics of intracellular and cell surface quinone reduction, hydroquinone oxidation and associations with cellular constituents using intact normoxic pulmonary arterial endothelial cells in culture and cells adapted to hyperoxia, as a model of oxidant stress. A panel of inhibitors and kinetic modeling will provide the means for functional and quantitative identification of the contributions of the quinone reductases and hydroquinone oxidases involved. Cell redox status will be manipulated experimentally to determine its role in the fate of the quinones that come in contact with the endothelial cells. Finally, the quinone reductases in the control and hyperoxia-adapted cells will be isolated and identified to further characterize their contributions to the net effect of both cell types to quinone fate. Since quinone reductases and hydroquinone oxidases are important in metabolism of a wide range of other redox active compounds, the results will have implications for endothelial processing of substances as well. The results will reveal pulmonary endothelial mechanisms involved in processing blood borne redox active substances, and their adaptation to oxidative stress, with implications for their pharmacological, physiological and toxicological activities throughout the body.

描述（由申请方提供）：肺内皮影响血液中氧化还原活性内源性、药理学、毒理学和饮食化合物的氧化还原状态。它通过充当由位于静脉和动脉循环之间的细胞表面和细胞内氧化还原酶组成的大型化学反应器表面来实现。内皮对这些化合物的氧化还原状态的影响影响其生物活性，包括促氧化或抗氧化作用、组织渗透和化学反应性。醌类化合物是一类重要的氧化还原活性化合物，具有广泛的生理、药理和毒理学活性。该提议的基础假设是肺内皮细胞对醌的氧化还原代谢决定了肺和内皮细胞、血浆以及下游血管和器官系统内的醌还原产物及其生物活性。拟议研究的目标是确定和量化与细胞和醌的性质有关的因素，这些因素决定了与肺内皮接触的给定醌的命运。具体目标是：1.鉴定和定量肺内皮醌还原酶和氢醌氧化酶介导的反应，这些反应有助于一系列具有不同物理和化学性质的醌的命运：2.确定醌还原酶的活动的依赖性，有助于肺内皮细胞氧化还原状态的一个给定的醌的命运：3。确定肺内皮细胞适应高氧对醌命运的氧化还原过程的影响。为了实现这些目标，一般的方法包括：测量细胞内和细胞表面醌还原，氢醌氧化和协会与细胞成分使用完整的常氧培养的肺动脉内皮细胞和细胞适应高氧，作为氧化应激模型的动力学。一个面板的抑制剂和动力学建模将提供功能和定量鉴定的醌还原酶和氢醌氧化酶的贡献所涉及的手段。将通过实验操作细胞氧化还原状态，以确定其在与内皮细胞接触的醌类命运中的作用。最后，在控制和高氧适应细胞中的醌还原酶将被分离和鉴定，以进一步表征它们对两种细胞类型对醌命运的净效应的贡献。由于醌还原酶和氢醌氧化酶在广泛的其他氧化还原活性化合物的代谢中是重要的，因此该结果也将对物质的内皮加工产生影响。这些结果将揭示参与处理血液中氧化还原活性物质的肺内皮机制，以及它们对氧化应激的适应，并对它们在全身的药理学、生理学和毒理学活性产生影响。