Mechanisms of Nitric Oxide Mediated Cell Injury

描述：最近的研究表明，多种炎症性疾病 与诱导型一氧化氮的上调有关 诱导型一氧化氮合酶(INOS)及其引发的自由基生成增强 一氧化氮(NO)。我们的长期目标是更好地理解氧化剂 而由高产量的NO产生的亚硝化化学可能有助于 与炎症相关的组织功能障碍和/或损伤。更多 具体地说，还没有确定它在多大程度上发挥作用 NO介导的S亚硝化反应引起的改变(增加了一个 NO+基团到硫醇残基)可能有助于细胞停滞。初步 我们实验室的研究表明，细胞内NO的产生 通过激活iNOS抑制细胞增殖，抑制线粒体 呼吸作用，引起谷胱甘肽代谢的改变，并介导 S-细胞蛋白质和多肽的亚硝化。这个项目的总体目标是 建议确定活性氮氧化物物种是如何从NO中衍生出来的 可能有助于细胞停滞，并更好地了解 与NO有关的细胞内亚硝化化学。我们建议 S-亚硝化反应有助于抑制细胞呼吸和 与NO产量增加相关的扩散。具体的 该项目的目标是：1)在被动反应之间建立因果联系 氮物种与NO介导的细胞抑制；2)研究 细胞介导的S亚硝硫醇的形成；3)确定细胞途径 对S-亚硝硫酚分解的影响；4)表征其分解机理。 活性氮氧化物抑制细胞呼吸并检测其 与细胞停滞的关系。为了解决这些具体目标，我们将重点放在 一个主要的生物系统，小鼠成纤维细胞系 表达人类形式的诱导型一氧化氮合酶。我们还将 细胞内S-亚硝硫醇代谢的动力学和平衡研究 使用最新开发的色谱、荧光光谱和 化学发光技术。这些研究可能对 细胞增殖和毒性，如在巨噬细胞诱导下观察到 与宿主防御机制有关的细胞抑制，在细胞增殖中 血管生成过程中的血管细胞，以及环境和医学中的 肺暴露于NO。

DESCRIPTION: Recent studies indicate that a variety of inflammatory disorders are associated with the up-regulation of the inducible form of nitric oxide synthase (iNOS) and the consequential enhanced production of the free radical nitric oxide (NO). Our long-term goal is to better understand how the oxidative and nitrosative chemistry emanating from high output of NO may contribute to the tissue dysfunction and/or injury associated with inflammation. More specifically, it has not yet been established to what extent functional alterations caused by NO-mediated S-nitrosation reactions (the addition of an NO+ group to a thiol residue) might contribute to cytostasis. Preliminary studies in our laboratory demonstrate that the intracellular production of NO via activation of iNOS inhibits cell proliferation, inhibits mitochondrial respiration, induces alteration in glutathione metabolism, and mediates the S-nitrosation of cellular proteins and peptides. The overall goal of this proposal is to determine how reactive nitrogen oxide species derived from NO may contribute to cytostasis and to obtain a better understanding of the intracellular nitrosative chemistry associated with NO. We propose that S-nitrosation reactions contribute to the inhibition of cell respiration and proliferation that is associated with increased NO production. The specific aims of this project are 1) to establish a causative link between reactive nitrogen species and NO-mediated cytostasis; 2) to examine the mechanisms of cell mediated formation of S-nitrosothiols; 3) to define the cellular pathways of S-nitrosothiol decomposition; 4) to characterize the mechanisms by which reactive nitrogen oxide species inhibit cell respiration and to examine their relationship with cytostasis. To address these specific aims, we will focus on one major biological system, a murine fibroblast cell line that constitutively expresses the human form of the inducible nitric oxide synthase. We will also examine the kinetics and equilibria of intracellular S-nitrosothiol metabolism using newly developed chromatographic, spectrofluorometric and chemiluminescence techniques. These studies may have important implications for cellular proliferation and toxicity, such as observed in macrophage-induced cytostasis associated with host defense mechanisms, in the proliferation of vascular cells during angiogenesis, and in environmental as well as medical pulmonary exposure to NO.