Cationic Amino Acid Transporters and Lung NO Production

阳离子氨基酸转运蛋白和肺 NO 产生

• 批准号: 7567823
• 负责人: LEIF D NELIN
• 金额: $ 4.61万
• 依托单位: RESEARCH INST NATIONWIDE CHILDREN'S HOSP
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-02-03 至 2010-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7567823
• 关键词: Address; Adult Respiratory Distress Syndrome; Affect; Arginine; Attention; Basic Amino Acid Transport Systems; Biological Assay; Biological Availability; Blood Vessels; Blood flow; Breathing; Cell Culture System; Cells; Chronic; Citrulline; Clinical; Clinical Trials; Critical Illness; Data; Development; Disease; Endothelial Cells; Equilibrium; Gene Expression Regulation; Gene Transfer; Goals; Hospitals; Hydrolysis; Hypertension; Hypoxia; Inflammation; Inflammatory; Intake; Ligase; Lipopolysaccharides; Lung; Lung diseases; MAP Kinase Gene; Mediating; Metabolism; Mitogen-Activated Protein Kinases; Nitric Oxide; Nitric Oxide Synthase; Outcome; Pathogenesis; Patients; Persistent Fetal Circulation Syndrome; Phosphotransferases; Physiological; Population; Production; Protein Biosynthesis; Protein Isoforms; Proteins; Pulmonary Hypertension; Rate; Rattus; Regulation; Research Personnel; Role; Signal Transduction; Small Interfering RNA; Testing; Tissues; Translations; Tumor Necrosis Factor-alpha; Tumor Necrosis Factors; Vascular remodeling; Vasodilation; Vasomotor; Western Blotting; Work; adenoviral-mediated; arginase; argininosuccinate lyase; cell growth regulation; design; extracellular; genetic manipulation; human TNF protein; improved; in vivo; inhaled nitric oxide; intravenous administration; knock-down; lung injury; neonatal pulmonary hypertension; programs; research study; src-Family Kinases; uptake; vasoconstriction

Nitric oxide (NO) is an important molecule involved in a myriad of physiological functions. In pulmonary hypertensive diseases, NO production is decreased resulting in vasoconstriction and vascular remodeling. While in pulmonary inflammatory diseases, NO production is increased resulting in tissue damage. NO is generated from L-arginine (L-arg) by the NO synthases (NOS). The cellular bioavailability of L-arg to NOS is determined in large part by uptake of extracellular L-arg via the cationic amino acid transporters (CAT). Preliminary studies suggest that manipulation of L-arg uptake modifies clinically important parameters in highly vulnerable patient populations. Thus, the studies described in the present application are focused on elucidation of the functional and mechanistic aspects of endothelial cell uptake of L-arg by CAT and its role in regulation of NO production in the lung. The long-term goals of these studies are to develop therapies that increase NO production by facilitating CAT-mediated L-arg uptake in pulmonary hypertensive diseases, and that decrease NO production by inhibiting CAT-mediated L-arg uptake in inflammatory lung diseases. The working hypothesis is that NO production can be modulated by control of L-arg bioavailability to NOS through alterations in CAT-mediated L-arg transport. The studies will address the hypothesis in 3 specific aims: 1) to test the hypothesis that alterations in CAT activities regulate NO production by altering the bioavailability of L-arg to NOS; 2) to test the hypothesis that Src-family tyrosine kinases and mitogen- activated protein kinases mediate inflammation-induced alterations in the expression of CAT and/or NOS; and 3) to test the hypothesis that gene transfer to regulate CAT expression in vivo will affect NO production in the lung, and thereby affect pulmonary vasomotor tone and lung injury. RELEVANCE: Therapies aimed at manipulating NO-mediated effects in lung diseases have centered on pharmacological inhibition of NO production or inhalation of exogenous NO, however a majority of these critically ill patients do not respond to these therapies. L-arg uptake represents a rate-limiting step in lung NO production. The present proposal will provide translational data necessary for the design of rational clinical trials to determine safe and effective pharmacological and genetic manipulations of L-arg uptake rates, and thereby NO production, in severe pulmonary diseases, such as ARDS and pulmonary hypertension.

一氧化氮（NO）是一种重要的分子，参与多种生理功能。肺 在高血压疾病中，NO产生减少，导致血管收缩和血管重塑。 而在肺部炎症性疾病中，NO产生增加，导致组织损伤。NO是 由L-精氨酸（L-arg）通过NO还原酶（NOS）产生。L-arg对NOS的细胞生物利用度为 这在很大程度上是通过阳离子氨基酸转运蛋白（CAT）摄取细胞外L-arg来确定的。 初步研究表明，L-arg摄取的操纵改变了临床上重要的参数， 非常脆弱的患者群体。因此，本申请中描述的研究集中于 通过CAT阐明内皮细胞摄取L-arg的功能和机制及其作用 调节肺中NO的产生。这些研究的长期目标是开发治疗方法， 通过促进CAT介导的肺动脉高压疾病中L-arg摄取增加NO产生， 其通过抑制炎性肺病中CAT介导的L-arg摄取来减少NO产生。的 工作假设是NO的产生可以通过控制L-arg对NOS的生物利用度来调节 通过CAT介导的L-arg转运的改变。这些研究将在3个具体的 目的：1）检验CAT活性的改变通过改变细胞内的NO含量来调节NO产生的假说。 L-arg对NOS的生物利用度; 2）检验Src家族酪氨酸激酶和促分裂原- 活化的蛋白激酶介导炎症诱导的CAT和/或NOS表达的改变; 3）验证体内转基因调控CAT表达会影响NO生成的假设 在肺中，从而影响肺血管张力和肺损伤。 相关性：旨在操纵肺部疾病中NO介导作用的治疗方法主要集中在 NO产生的药理学抑制或外源性NO的吸入，然而，大多数这些 重症患者对这些疗法没有反应。L-arg摄取是肺NO代谢的限速步骤， 生产本提案将为合理的临床设计提供必要的翻译数据。 确定L-arg摄取率的安全有效的药理学和遗传学操作的试验，以及 从而在严重的肺部疾病如ARDS和肺动脉高压中产生NO。