Nitric Oxide in Pulmonary Hypertension

一氧化氮与肺动脉高压

• 批准号: 8857812
• 负责人: Serpil C. Erzurum
• 金额: $ 0.31万
• 依托单位: CLEVELAND CLINIC LERNER COM-CWRU
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-04-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8857812
• 关键词: Abnormal Cell; Accounting; Altitude; Antioxidants; Apoptosis; Biochemical; Biological Models; Blood Circulation; Blood Vessels; Bone Marrow; Boxing; Caring; Cell Culture Techniques; Cell Line; Cell Respiration; Cell Survival; Cell model; Cells; Clinical; Clinical Research; Data; Disease; Endothelial Cells; Enzymes; Erythropoietin; Event; Figs - dietary; Fostering; Functional disorder; Glucose; Glycolysis; Goals; Grant; Gray unit of radiation dose; Growth; Health; Hepatocyte Growth Factor; Human; Hypoxia; Hypoxia Inducible Factor; Immunodeficient Mouse; Implant; In Vitro; Knowledge; Link; Lung; Lung Transplantation; Malignant Neoplasms; Manganese Superoxide Dismutase; Measures; Metabolic; Metabolism; Methods; Mitochondria; Modeling; Molecular; Mus; Mutation; NOD/SCID mouse; Nature; Nitric Oxide; Nitric Oxide Synthase; Normal Cell; Outcome; Pathologic; Pathway interactions; Patient Care; Patients; Phenotype; Phosphorylation; Phosphorylation Inhibition; Physiological; Plasma; Population; Positron-Emission Tomography; Primary Cell Cultures; Production; Proteins; Pulmonary Hypertension; Pulmonary artery structure; Regulation; Research; Resistance; Respiration; STAT3 gene; Signal Transduction; Stat3 protein; Testing; Text; Threonine; Tibet; Time; Transducers; Vascular Diseases; Vascular Endothelial Cell; Vasodilator Agents; Work; Xenograft Model; Xenograft procedure; angiogenesis; autocrine; base; caveolin 1; endothelial dysfunction; glucose analog; glucose uptake; hemodynamics; human NOS3 protein; hypertension control; hypoxia inducible factor 1; improved; in vivo; matrigel; multidisciplinary; paracrine; patient population; pressure; progenitor; programs; pulmonary arterial hypertension; pulmonary artery endothelial cell; response; translational study

DESCRIPTION (provided by applicant): Pulmonary arterial hypertension (PAH) is a fatal disease associated with increased pulmonary artery pressure (PAP) and abnormalities in blood vessel growth. The excessive growth of the vascular endothelial cells is the focus of our research. Four years ago, we established methods for culture of pulmonary artery endothelial cells (PAEC) from PAH and donor lungs. The PAEC in culture reflect abnormalities found in PAH lungs and patients in vivo, and made it possible to test our hypotheses in translational mechanistic studies. We found that PAH PAEC have enhanced proliferation & survival, which is dependent on activation of signal transducer and activator of transcription-3 (STAT3), a fundamental regulator of cell survival and angiogenesis. The PAH cells have impaired production of the vasodilator nitric oxide (NO) due to post- translational mechanisms that include phosphorylation/inhibition of endothelial NO synthase (eNOS). In association with low NO, the cells have reduced mitochondria numbers & respiration, which is accompanied by ~3-fold increase in glycolysis for energy production. The shift to anaerobic glycolytic metabolism is related to expression of the pro-survival and pro-angiogenic signal transducer, hypoxia-inducible factor -1a (HIF-1a). Physiologic effects classically ascribed to HIF-expression [increased lung glucose uptake by 18F- fluoro-deoxy-glucose analogue - positron emission tomography (FDG-PET), high-levels of plasma erythropoietin (Epo) and mobilization of bone marrow progenitors] are present in patients and quantitatively associated with PAP. The HIF-expression is mechanistically linked to the alterations in STAT3, NO and Mn superoxide dismutase (MnSOD). Preliminary data show that the PAH PAEC secrete the potent growth- stimulatory & bone marrow-mobilizing hepatocyte growth factor (HGF). Present at high-levels in patient plasma and PAH cell cultures, HGF signals through STAT3 and induces HIF-1a, and is itself induced by STAT3 and increased by hypoxia, which endows the cells with autocrine and paracrine proliferative and pro-angiogenic effects. Here, we hypothesize that PAH endothelial cells have decreased NO production by eNOS and activation of survival pathways STAT3 and HIF-1a. These biochemical mechanisms account for the proliferative, glycolytic, and strongly pro-angiogenic phenotype of the cells. We identify mechanisms of reduced eNOS activity in aim 1, and focus on HIF-expression and mechanisms accounting for its expression in aim 2. In aim 3, we test if HIF-expression is mechanistically important in PAH pathophysiology using the primary cell culture model, a xenograft model of PAH cells in immunodeficient mice and a longitudinal clinical study, in which we test whether experimental outcomes of HIF-effects are associated with clinical outcomes in patients over time. Overall our goals are to define the pathophysiology of the abnormal vascular growth in PAH, and in so doing, apply the knowledge to improve the care of patients.

描述（由申请人提供）：肺动脉高压（PAH）是一种与肺动脉压力（PAP）增加和血管生长异常相关的致命疾病。血管内皮细胞的过度生长是我们研究的重点。四年前，我们建立了从 PAH 和供体肺中培养肺动脉内皮细胞 (PAEC) 的方法。培养物中的 PAEC 反映了 PAH 肺部和患者体内发现的异常，并使得在转化机制研究中检验我们的假设成为可能。我们发现 PAH PAEC 具有增强的增殖和存活能力，这依赖于信号转导器和转录激活剂 3 (STAT3) 的激活，STAT3 是细胞存活和血管生成的基本调节因子。由于翻译后机制，包括内皮一氧化氮合酶（eNOS）的磷酸化/抑制，PAH细胞产生血管扩张剂一氧化氮（NO）受到损害。与低NO相关，细胞线粒体数量和呼吸减少，伴随着能量产生的糖酵解增加约3倍。向无氧糖酵解代谢的转变与促生存和促血管生成信号转导器缺氧诱导因子-1a (HIF-1a) 的表达有关。存在通常归因于 HIF 表达的生理效应 [18F-氟脱氧葡萄糖类似物 - 正电子发射断层扫描 (FDG-PET) 增加肺葡萄糖摄取、高水平的血浆促红细胞生成素 (Epo) 和骨髓祖细胞的动员]与 PAP 定量相关。 HIF 表达在机制上与 STAT3、NO 和 Mn 超氧化物歧化酶 (MnSOD) 的改变有关。初步数据表明，PAH PAEC 分泌有效的生长刺激和骨髓动员肝细胞生长因子 (HGF)。 HGF 在患者血浆和 PAH 细胞培养物中以高水平存在，通过 STAT3 发出信号并诱导 HIF-1a，并且其本身由 STAT3 诱导并因缺氧而增加，从而赋予细胞自分泌和旁分泌增殖和促血管生成作用。在这里，我们假设 PAH 内皮细胞减少了 eNOS 产生的 NO 以及激活了生存途径 STAT3 和 HIF-1a。这些生化机制解释了细胞的增殖、糖酵解和强促血管生成表型。我们在目标 1 中确定了 eNOS 活性降低的机制，在目标 2 中重点关注 HIF 表达及其表达机制。在目标 3 中，我们使用原代细胞培养模型测试 HIF 表达在 PAH 病理生理学中是否具有重要的机制。免疫缺陷小鼠 PAH 细胞的异种移植模型和一项纵向临床研究，其中我们测试 HIF 效应的实验结果是否与患者随时间的临床结果相关。总体而言，我们的目标是确定 PAH 异常血管生长的病理生理学，并在此过程中应用这些知识来改善患者的护理。