Prostacyclin Synthase and Receptors in Pulmonary Arterial Hypertension

肺动脉高压中的前列环素合酶和受体

• 批准号: 8134960
• 负责人: MARK W GERACI
• 金额: $ 11.48万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-15 至 2013-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8134960
• 关键词: Abbreviations; Accounting; Affect; Agonist; Biological Models; Blood Pressure; Blood Vessels; Cells; Chromosomal Loss; Complex; CpG Islands; Data; Development; Disease; Down-Regulation; Effectiveness; Endothelial Cells; Endothelin; Epigenetic Process; Epoprostenol; Epoprostenol Receptors; Fluorescent in Situ Hybridization; Frequencies; Gene Expression; Gene Expression Regulation; Genes; Genetic; Haplotypes; Heart; Human; Hypertension; Hypertrophy; Iloprost; Incidence; Lead; Length; Lesion; Loss of Heterozygosity; Lung; Lung diseases; Mediating; Membrane; Methylation; Minisatellite Repeats; Morbidity - disease rate; Mus; Nuclear; Nuclear Receptors; Onset of illness; Outcome; Pathology; Pathway interactions; Patients; Peroxisome Proliferator-Activated Receptors; Persons; Pharmaceutical Preparations; Population; Predisposition; Promoter Regions; Prostacyclin synthase; Prostaglandin-Endoperoxide Synthase; Prostaglandins I; Pulmonary Hypertension; Pulmonary artery structure; Rattus; Relative (related person); Research; Role; Severities; Signal Pathway; Signal Transduction; Single Nucleotide Polymorphism; Smooth Muscle; Smooth Muscle Myocytes; Transgenic Mice; Transgenic Organisms; Translating; Variant; Vascular remodeling; Woman; Work; analog; blood pump; cell growth; cell type; chromatin immunoprecipitation; combinatorial; gene repression; human disease; hypertension treatment; improved; inhibitor/antagonist; laser capture microdissection; mouse model; novel; phosphodiesterase V; pre-clinical; pressure; primary pulmonary hypertension; promoter; public health relevance; pulmonary arterial hypertension; receptor; rosiglitazone

DESCRIPTION (provided by applicant): Pulmonary Arterial Hypertension (PAH) is characterized by elevations in pulmonary artery pressure, vascular remodeling, and hyperproliferation of endothelial cells. While there is no cure or preventative treatment for this disease at present, newer targeted therapies can improve outcomes by altering vascular tone using prostacyclin (PGI2) analogues, dual endothelin antagonists, or phosphodiesterase - 5 inhibitors. Recent progress in the understanding of genetic aberrations in PAH suggests that it is a complex disorder and that modifier genes are potentially involved in mediating increased susceptibility and severity. Two genes that affect the level of prostacyclin signaling, prostacyclin synthase (PGIS) and the nuclear receptor PPAR?, are down- regulated in patients with PAH. Disruption of PGI2 signaling through the PPAR? pathway leads to aberrant cell growth. Our hypothesis proposes that PGI2 can signal through either PGIR or PPAR?. We hypothesize that signaling through PGIR results in more prominent effects on vascular tone (RV pressures, RV hypertrophy) while PPAR? stimulation results in more effects on vascular remodeling. The research proposed here focuses on 1) the effectiveness of augmenting signaling through the two different PGI2 receptors as a treatment to reverse remodeling of both smooth muscle and endothelial cells in PAH (PPAR?) or vascular tone (PGIR), 2) the potential modifier gene role of the PGIS and gene in conferring a predisposition to PAH and an increased likelihood of developing severe PAH, and 3) the mechanism of PGIS and PPAR? loss of expression in human disease. We will use two sophisticated murine modeling systems generated by our group to dissect the relative contribution of the two receptors to the development of PAH. Our proposed pre-clinical rat studies establish the effectiveness of a combinatorial treatment using a PGI2 analogue and a PPAR? agonist may quickly translate in to a human combined drug trial. Our preliminary work demonstrates that sequence variation in the proximal PGIS promoter region affects promoter activity leading to low PGIS expression, thus establishing a predisposition to PAH. We will sequence the PGIS promoters from familial pulmonary hypertension, correlating specific haplotypes with disease on-set, severity, and morbidity. Finally, because epigenetic silencing and chromosomal loss are common mechanisms of gene expression down-regulation, we will determine if either is responsible for PGIS or PPAR? down-regulation in micro-dissected PAH lesions using methylation specific PCR (MSP) and fluorescence in situ hybridization (FISH). Specific Aim 1: Delineate the contributions of PGIS and PPAR? pathways to PAH susceptibility and severity. Specific Aim 2: Define transcriptional activity of PGIS promoter sequence variations in relevant primary cells types, and their frequency and correlation in a defined human population. Specific Aim 3: Determine if methylation silencing and/or allelic loss account for PGIS and PPAR? down- regulation in micro-dissected lesions from patients with severe PAH. PUBLIC HEALTH RELEVANCE: Pulmonary Arterial Hypertension (PAH) is a very serious lung disease in which blood pressure in the lung's pulmonary artery increases making the heart work harder to pump blood into the lung. PAH is very rare with an annual incidence of 1 to 2 per million and occurs more often in women. While there is no cure or preventative treatment, newer targeted therapies can improve outcomes. This project will help us understand how current treatments are reducing the changes in the pulmonary artery that lead to the high blood pressure and may lead to newer therapies that are more effective in controlling the progression and severity of PAH.

描述（由申请人提供）：肺动脉高压（PAH）的特征为肺动脉压升高、血管重塑和内皮细胞过度增殖。虽然目前这种疾病没有治愈或预防性治疗，但新的靶向治疗可以通过使用前列环素（PGI 2）类似物，双重内皮素拮抗剂或磷酸二酯酶-5抑制剂改变血管张力来改善结局。对PAH遗传畸变理解的最新进展表明，PAH是一种复杂的疾病，修饰基因可能参与介导易感性和严重程度增加。影响前列环素信号水平的两个基因，前列环素合酶（PGIS）和核受体PPAR？，在PAH患者中表达下调。破坏PGI 2信号通过过氧化物酶体增殖物激活受体？导致细胞生长异常。我们的假设提出PGI 2可以通过PGIR或PPAR？发出信号。我们推测，通过PGIR信号的结果在更突出的影响血管紧张度（右心室压力，右心室肥大），而过氧化物酶体增殖物激活受体？刺激对血管重塑的影响更大。本文提出的研究重点是1）通过两种不同的PGI 2受体增强信号传导作为逆转PAH（PPAR？）平滑肌和内皮细胞重塑的治疗方法的有效性。或血管紧张度（PGIR），2）PGIS和基因在赋予PAH易感性和增加发生重度PAH的可能性方面的潜在修饰基因作用，3）PGIS和PPAR？在人类疾病中失去表达。我们将使用两个复杂的小鼠模型系统，由我们的小组产生的两个受体的PAH的发展的相对贡献进行剖析。我们提出的临床前大鼠研究建立了使用PGI 2类似物和PPAR？激动剂可能很快转化为人体联合药物试验。我们的初步工作表明，在近端PGIS启动子区域的序列变异影响启动子活性，导致低PGIS表达，从而建立了PAH的易感性。我们将对家族性肺动脉高压的PGIS启动子进行测序，将特定的单倍型与疾病的发作、严重程度和发病率相关联。最后，由于表观遗传沉默和染色体丢失是基因表达下调的常见机制，我们将确定是否是负责PGIS或PPAR？使用甲基化特异性PCR（MSP）和荧光原位杂交（FISH）在显微解剖的PAH病变中下调。具体目标1：描述PGIS和PPAR的贡献？PAH易感性和严重程度的途径。具体目标二：定义相关原代细胞类型中PGIS启动子序列变异的转录活性，以及它们在特定人群中的频率和相关性。具体目标3：确定甲基化沉默和/或等位基因丢失是否是PGIS和PPAR的原因？重度PAH患者的显微解剖病变中的下调。 公共卫生相关性：肺动脉高压（PAH）是一种非常严重的肺部疾病，其中肺的肺动脉中的血压增加，使心脏更难将血液泵入肺部。PAH非常罕见，年发病率为1 - 2/百万，女性更常见。虽然没有治愈或预防性治疗，但新的靶向治疗可以改善结果。该项目将帮助我们了解目前的治疗方法如何减少导致高血压的肺动脉变化，并可能导致更有效控制PAH进展和严重程度的新疗法。

项目成果

Genetics and genomics of pulmonary arterial hypertension.

• DOI: 10.1016/j.jacc.2009.04.015
• 发表时间: 2009-06-30
• 期刊: JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY
• 影响因子: 24
• 作者: Machado, Rajiv D.;Eickelberg, Oliver;Elliott, C. Gregory;Geraci, Mark W.;Hanaoka, Masayuki;Loyd, James E.;Newman, John H.;Phillips, John A., III;Soubrier, Florent;Trembath, Richard C.;Chung, Wendy K.
• 通讯作者: Chung, Wendy K.

Genomics of pulmonary arterial hypertension: implications for therapy.

• DOI: 10.1016/j.hfc.2009.08.001
• 发表时间: 2010-01
• 期刊: Heart failure clinics
• 影响因子: 3.4
• 作者: Geraci MW;Bull TM;Tuder RM
• 通讯作者: Tuder RM