RTP-801 in Cigarette Smoke-Emphysema

RTP-801在香烟烟雾-肺气肿中的应用

• 批准号: 8064153
• 负责人: Rubin M. Tuder
• 金额: $ 33.21万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-02-15 至 2015-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8064153
• 关键词: Abbreviations; Address; Adenoviruses; Air; Alveolar; Alveolar Cell; Antioxidants; Apoptosis; Brain; Bronchoalveolar Lavage; Cardiovascular Diseases; Cell Death; Cells; Cellular Stress; Cellular Stress Response; Chronic Obstructive Airway Disease; Cigarette smoke-induced emphysema; Complex; Data; Disease; Erythroid; Fibroblasts; Figs - dietary; Gene Expression; Gene Proteins; Genes; Growth Factor; Human; Hypoxia Inducible Factor; Immunofluorescence Immunologic; Immunohistochemistry; In Vitro; Inflammation; Inflammatory; Injury; Intervention; Knock-out; Knockout Mice; Knowledge; Left; Lung; Lung Inflammation; Lung diseases; Maintenance; Manuscripts; Mediating; Mediator of activation protein; Medicine; Molecular; Morbidity - disease rate; Mus; Muscle; NF-kappa B; Natural Immunity; Nature; Nuclear; Oxidative Stress; Oxygen; Paper; Pathogenesis; Patients; Physiological; Process; Proto-Oncogene Proteins c-akt; Pulmonary Emphysema; Role; Screening procedure; Signal Pathway; Signal Transduction; Sirolimus; Small Interfering RNA; Stress; Transduction Gene; Transgenic Mice; Tuberous sclerosis protein complex; Up-Regulation; Virus; Work; acquired immunity; biological adaptation to stress; cell growth; cell injury; cigarette smoke-induced; cigarette smoking; design; dynein light chain; human FRAP1 protein; in vivo; insight; lung injury; mTOR protein; mortality; novel; pollutant; programs; response; sensor; small hairpin RNA; transcription factor

DESCRIPTION (provided by applicant): Our work over the past 10 years has uncovered that the disruption of alveolar structural and molecular maintenance program by cigarette smoke contributes to the pathogenesis of emphysema. The present application is centered on the concept that environmental stresses, such as caused by cigarette smoke (CS) and pollutants activate "rheostat" molecules that govern harmful alveolar septal cell responses involving oxidative stress, apoptosis, and alveolar inflammation. In line with this overall paradigm, we propose mechanistic studies targeting the cellular stress response gene RTP801, which was discovered in a screening of genes upregulated by hypoxia inducible factor-1a (HIF-a) and shown to induce oxidative stress and apoptosis. RTP801 inactivates mTORC1 (for mammalian target for rapamycin complex 1), which controls a central cell signaling pathway that acts as a physiological molecular sensor of environmental stresses. mTORC therefore integrates growth factor signaling, cell growth, and survival adaptation to adverse environmental conditions. We hypothesize that oxidative stress caused by CS activates RTP801 expression, which suppresses mTOR signaling in alveolar cells, leading to alveolar cell inflammation and apoptosis. Upregulation of RTP801 causes oxidative stress-triggered release of dynein-light chain molecule 8 (LC8) from I?B and NF-?B-activation. Our preliminary data demonstrate that RTP801 knockout mice are protected against lung inflammation, apoptosis, and emphysema caused by cigarette smoke. Specific Aim 1 will demonstrate that the stress response gene RTP801 is required for cigarette smoke- induced emphysema in mice. Specific Aim 2 will demonstrate that RTP801-induced lung inflammation and apoptosis by cigarette smoke are mediated by suppression of its downstream target mTOR. Specific Aim3 will demonstrate that RTP801 suppression of mTOR signaling causes oxidative stress-dependent displacement of the dynein-light chain molecule 8 (LC8) from I?B, leading to activation of NF-?B. These aims rely on a translational and comprehensive approach that includes knockout and transgenic mice, in vivo and in vitro manipulation of RTP801/mTOR/AKT gene expression and signaling with adenoassociated virus or adenovirus gene transduction, and siRNA or short hairpin RNA, complementary pharmacological interventions aimed at mTOR and oxidative stress, and detailed morphometric and cellular assessments of alveolar injury. Our proposal advances the concept that CS-mediated lung injury in emphysema is controlled by alveolar septal cells, as the result of the interaction of oxidative stress and molecular switches involved in cell stress responses. This interaction mediated by RTP801 may constitute a critical modulator of innate and acquired immunity and of cellular protection by growth factors, which are central to the pathogenesis of emphysema. PUBLIC HEALTH RELEVANCE: Chronic obstructive pulmonary diseases (COPD) are the 4th leading cause of mortality and morbidity, with worldwide impact. Emphysema is part of COPD and compromises about 20-60% of patients with the disease. In emphysema, the lung literally disappears, leaving behind large holes, a profound inability to breath air into and out of the lungs, and decrease in the ability of the lungs to get oxygen. Our concept is that environmental stresses, such as those cause by cigarette smoke, cause the activation of cellular responses that are originally designed to protect the host. One of these sensor molecules is RTP801. The activation of RTP801 by cigarette smoke activates inflammation and causes lung cell death. Our proposal is to prove that RTP801 is involved in emphysema caused by cigarette smoke, and the potential mechanisms involved in this process. Our studies have relevance to lung diseases, and also to other manifestations of disease caused by cigarette smoke, such as weigh loss due to muscle damage and cardiovascular disease.

描述（由申请人提供）：我们过去 10 年的工作发现，香烟烟雾对肺泡结构和分子维持程序的破坏导致了肺气肿的发病机制。本申请的核心概念是，诸如由香烟烟雾(CS)和污染物引起的环境应激会激活“变阻器”分子，该分子控制涉及氧化应激、细胞凋亡和肺泡炎症的有害肺泡间隔细胞反应。根据这一总体范式，我们提出针对细胞应激反应基因 RTP801 的机制研究，该基因是在筛选缺氧诱导因子 1a (HIF-a) 上调的基因时发现的，并被证明可诱导氧化应激和细胞凋亡。 RTP801 使 mTORC1（雷帕霉素复合物 1 的哺乳动物靶标）失活，mTORC1 控制着中央细胞信号传导通路，充当环境压力的生理分子传感器。因此，mTORC 整合了生长因子信号传导、细胞生长和对不利环境条件的生存适应。我们假设CS引起的氧化应激激活RTP801表达，从而抑制肺泡细胞中的mTOR信号传导，导致肺泡细胞炎症和凋亡。 RTP801 的上调会导致氧化应激触发 IκB 和 NF-κB 激活中动力蛋白轻链分子 8 (LC8) 的释放。我们的初步数据表明，RTP801 基因敲除小鼠可以免受香烟烟雾引起的肺部炎症、细胞凋亡和肺气肿的影响。具体目标 1 将证明应激反应基因 RTP801 是香烟烟雾诱发的小鼠肺气肿所必需的。具体目标 2 将证明香烟烟雾引起的 RTP801 诱导的肺部炎症和细胞凋亡是通过抑制其下游靶标 mTOR 介导的。具体的 Aim3 将证明 RTP801 对 mTOR 信号传导的抑制会导致 IκB 中动力蛋白轻链分子 8 (LC8) 的氧化应激依赖性置换，从而导致 NF-κB 的激活。这些目针对 mTOR 和氧化应激，以及肺泡损伤的详细形态测量和细胞评估。我们的建议提出了这样的概念：CS 介导的肺气肿肺损伤是由肺泡间隔细胞控制的，这是氧化应激和参与细胞应激反应的分子开关相互作用的结果。 RTP801 介导的这种相互作用可能构成先天性和获得性免疫以及生长因子细胞保护的关键调节剂，而生长因子是肺气肿发病机制的核心。 公共卫生相关性：慢性阻塞性肺疾病 (COPD) 是导致死亡和发病的第四大原因，具有全球影响。肺气肿是 COPD 的一部分，约 20-60% 的患者患有肺气肿。在肺气肿中，肺部实际上消失了，留下大洞，严重无法将空气吸入和呼出肺部，并且肺部获取氧气的能力下降。我们的概念是，环境压力（例如由香烟烟雾引起的压力）会激活最初旨在保护宿主的细胞反应。 RTP801 就是这些传感器分子之一。香烟烟雾激活 RTP801 会激活炎症并导致肺细胞死亡。我们的建议是证明RTP801与香烟烟雾引起的肺气肿有关，以及该过程中涉及的潜在机制。我们的研究与肺部疾病以及香烟烟雾引起的其他疾病表现相关，例如肌肉损伤和心血管疾病引起的体重减轻。