Nitric Oxide Production and Reactions in the Lung

肺中一氧化氮的产生和反应

• 批准号: 7822969
• 负责人: Serpil C. Erzurum
• 金额: $ 2.37万
• 依托单位: CLEVELAND CLINIC LERNER COM-CWRU
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-01 至 2010-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7822969
• 关键词: 3-nitrotyrosine; Abnormal Endothelial Cell; Accounting; Arginine; Arteries; BMPR2 gene; Biology; Blood Vessels; Cell Culture Techniques; Cell Proliferation; Cells; Consumption; DNA biosynthesis; Data; Disease; Endothelial Cells; Environment; Enzymes; Etiology; Evaluation; Event; Fingerprint; Functional disorder; Gene Targeting; Genes; Goals; Growth; Half-Life; Human Herpesvirus 8; Hypertension; In Vitro; Infection; Interleukin-6; Investigation; Lead; Longitudinal Studies; Lung; Measures; Mediating; Methods; Modeling; Mutation; Nitrates; Nitric Oxide; Nitric Oxide Synthase; Ornithine; Outcome; Oxidants; Pathogenesis; Pathway interactions; Patient Care; Patients; Peroxonitrite; Production; Proteomics; Pulmonary Hypertension; Pulmonary artery structure; RNA Interference; Reaction; Regulation; STAT protein; STAT3 gene; Signal Transduction; Stat3 protein; Superoxide Dismutase; Superoxides; Testing; Transcriptional Activation; Tube; Tyrosine; VEGFA gene; Vascular Endothelial Growth Factors; Vasodilation; Vasodilator Agents; Work; angiogenesis; arginase; arginylarginine; autocrine; bone morphogenetic protein receptor type II; disorder control; enzyme substrate; hemodynamics; hypertension control; improved; in vivo; migration; neutralizing antibody; novel; pressure; primary pulmonary hypertension; pulmonary artery endothelial cell; research study; stem

DESCRIPTION (provided by applicant): Primary pulmonary hypertension (PPH) is a fatal disease of unknown etiology characterized by impaired regulation of both pulmonary hemodynamics and vascular growth. Our preliminary data show that primary pulmonary artery endothelial cells (PAEC) from PPH lung have enhanced proliferation, migration and abnormal tube formation in vitro. The signal transducer and activator of transcription (STAT) 3, recently identified as a critical regulator for angiogenesis, is persistently activated in PPH PAEC, but not in control cells. High-level expression of putative downstream target genes, arginase II and vascular endothelial growth factor (VEGF), are present only in PPH PAEC. Previously, we showed that diminished vasodilator nitric oxide (NO) is important in the pathophysiology of PPH, but NO synthases (NOS) expression are intact. Here, we propose a post-translational mechanism for low NO, i.e. arginase II, an enzyme that competes for the NOS substrate arginine, is increased. Thus, we hypothesize that the pathogenesis of PPH stems from abnormal endothelial cells, which have persistent STAT3 activation with consequent expression of VEGF and arginase II, that leads to increased proliferation, deregulated angiogenesis, and loss of NO. Initially, we will quantitate proliferation, migration and tube formation of PPH PAEC in comparison to healthy and disease controls. To identify mechanisms that account for the altered biology of PPH cells and low NO in PPH, we focus our investigations on arginase II using strategies of over-expression, RNA silencing or pharmacologic inhibition of arginase under conditions that assess enzyme substrate and product effects, and NO synthesis. To investigate mechanisms for high-level arginase expression in PPH, we plan to analyze STAT-mediated transcriptional activation of arginase II. Our studies also include evaluation for type II bone morphogenetic protein receptor (BMPR2) mutations and Human Herpesvirus 8 (HHV8) infection, both implicated in PPH pathogenesis, and use proteomic methods to discover novel differences between control and PPH. Our previous study showed an inverse correlation of NO to pulmonary artery pressure. Here, we propose a longitudinal study of PPH patients to test our hypothesis that determinants of NO synthesis, i.e. arginase and arginine, predict outcomes in PPH. Taken together, these studies will conclusively reveal fundamental and inherent alterations in PPH endothelial cells, identify the causal mechanisms, and lead to novel therapies for treatment of PPH.

描述（由申请人提供）：原发性肺动脉高压（PPH）是一种病因不明的致死性疾病，其特征是肺血流动力学和血管生长调节受损。我们的初步数据表明，PPH肺原代肺动脉内皮细胞（PAEC）在体外增殖、迁移和异常管形成增强。转录信号换能器和激活因子（STAT） 3，最近被确定为血管生成的关键调节因子，在PPH PAEC中持续激活，但在对照组细胞中不激活。推测的下游靶基因精氨酸酶II和血管内皮生长因子（VEGF）的高水平表达仅存在于PPH PAEC中。先前，我们发现血管扩张剂一氧化氮（NO）的减少在PPH的病理生理中很重要，但NO合成酶（NOS）的表达是完整的。在这里，我们提出了低NO的翻译后机制，即精氨酸酶II，一种与NOS底物精氨酸竞争的酶，增加。因此，我们假设PPH的发病机制源于内皮细胞异常，内皮细胞持续的STAT3激活导致VEGF和精氨酸酶II的表达，从而导致增殖增加，血管生成失控和NO的丢失。首先，我们将量化PPH PAEC与健康和疾病对照的增殖、迁移和管形成。为了确定PPH细胞生物学改变和PPH中低NO的机制，我们在评估酶底物和产物效应以及NO合成的条件下，利用精氨酸酶的过表达、RNA沉默或药物抑制策略，重点研究了精氨酸酶II。为了研究PPH中精氨酸酶高水平表达的机制，我们计划分析stat介导的精氨酸酶II的转录激活。我们的研究还包括评估II型骨形态发生蛋白受体（BMPR2）突变和人类疱疹病毒8 （HHV8）感染，两者都与PPH的发病机制有关，并使用蛋白质组学方法发现对照组和PPH之间的新差异。我们之前的研究显示NO与肺动脉压呈负相关。在这里，我们建议对PPH患者进行纵向研究，以验证我们的假设，即NO合成的决定因素，即精氨酸酶和精氨酸，预测PPH的预后。综上所述，这些研究将最终揭示PPH内皮细胞的基本和固有改变，确定其因果机制，并导致治疗PPH的新疗法。