MASS SPECTROMETRIC IDENTIFICATION OF NEW LIPID MEDIATORS

新脂质介质的质谱鉴定

• 批准号: 6520392
• 负责人: MICHAEL BALAZY
• 金额: $ 19.44万
• 依托单位: NEW YORK MEDICAL COLLEGE
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-03-01 至 2006-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6520392
• 关键词: arachidonate; bacterial disease; chemical synthesis; cyclic GMP; electrospray ionization mass spectrometry; endotoxins; free radical oxygen; high performance liquid chromatography; infrared spectrometry; laboratory rat; lipopolysaccharides; membrane; membrane lipids; nitrogen oxides; nuclear magnetic resonance spectroscopy; oxidative stress; pathology; phospholipids; plasmalogens; protein degradation; technology /technique development; tissue /cell preparation; toxicant interaction

DESCRIPTION (Applicant's abstract): The overall aim of this application is to characterize new mechanisms of biological membrane injury resulting form infection with bacterial endotoxin (LPS). The role of free radicals in LPS-induced endotoxemia is becoming well established, however, little is known about the processes involved in the damage to biomembrane lipids by nitrogen dioxide (NO2) radical (a product of nitric oxide oxidation). We have developed a new methodology based on electrospray tandem mass spectrometry, which allows identification and quantification of specific lipid products formed by the reaction of NO2 with arachidonic acid. Preliminary studies have revealed that this reaction generates a complex mixture of lipids containing characteristic products: trans isomers of arachidonic acid and lipids containing nitrogen-carbon bond (nitroeicosanoids). In addition, plasmalogen phospholipids reacted with NO2, which resulted in complete removal of this group of lipids and generation of 1 -lyso-phospholipids. We hypothesize that increased production of NO generates NO2. which is a key radical that targets arachidonic acid and phospholipids. thereby causing membrane injury. Specific aims are to: 1) study relationships between the magnitude of trans-arachidonic acid generation and other markers of free radical damage (isoprostaglandin, nitrite/nitrate, nitrotyrosine); 2) examine the nitration of arachidonic acid and the effects of nitroeicosanoids on NO and cGMP levels in tissues; 3) characterize modifications of plasmalogen phospholipids in endotoxemia. In order to address the role of NO, L-NMA, a NO synthase inhibitor will be used to prevent generation of NO. Uric acid was shown to scavenge NO2, and thus serve as a good probe to study effects of NO2 in LPS-induced injury. Thus these probes will be used to determine the role of NO and NO2 in arachidonic acid isomerization, nitration and plasmalogen degradation. We anticipate that in the long term the proposed studies will provide a foundation for a rational design of new strategies for development of new drugs (inhibitors of lipid isomexization and nitration), and therapies to treat symptoms of sepsis related to the N02-induced cytotoxicity.

描述(申请人摘要)：本申请的总体目标是 细菌引起生物膜损伤的新机制 感染细菌内毒素(LPS)。自由基在人类免疫系统中的作用 脂多糖诱导的内毒素血症已得到证实，然而，鲜为人知。 关于氮气对生物膜脂类损伤的过程 二氧化氮(NO2)自由基(一氧化氮氧化的产物)。我们已经开发出 一种基于电喷雾串联质谱仪的新方法，允许 细菌形成的特定脂类产物的鉴定和定量 NO2与花生四烯酸的反应。初步研究表明， 这种反应会产生一种复杂的脂类混合物，其中含有 产品：花生四烯酸的反式异构体和含有 氮-碳键(硝基二十烷)。此外，纤溶酶原磷脂 与NO2反应，导致这组脂质完全去除 和1-溶血磷脂的生成。我们假设增加了 NO的产生会产生NO2。这是一个针对花生四烯酸的关键激进分子 酸和磷脂。从而造成膜损伤。具体目标是： 1)研究了反式花生四烯酸的大小与 产生和其他自由基损伤的标志物(异前列腺素， 亚硝酸盐/硝酸盐、硝基酪氨酸)；2)检测花生四烯酸的硝化 以及硝基二十烷类化合物对组织中NO和cGMP水平的影响； 内毒素血症中纤溶酶原磷脂的修饰特征。在……里面 为了解决NO的作用，一氧化氮合酶抑制剂L-NMA将用于 防止NO的产生。尿酸被证明可以清除NO2，从而服务于 为研究NO2在脂多糖诱导的损伤中的作用提供了一个很好的探针。因此，这些 将使用探针来确定NO和NO2在花生四烯酸中的作用 异构化、硝化和血浆蛋白原降解。我们预计这将在 长远来说，建议的研究将为合理的设计提供基础。 开发新药(脂类抑制剂)的新策略 异构化和硝化)，以及治疗脓毒症相关症状的方法 对N02诱导的细胞毒作用。