RTP-801 in Cigarette Smoke-Emphysema

RTP-801在香烟烟雾-肺气肿中的应用

• 批准号: 8396393
• 负责人: Rubin M. Tuder
• 金额: $ 31.2万
• 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/8396393
• 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; 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; public health relevance; response; screening; 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.

描述（由申请人提供）：我们在过去10年的工作中发现，香烟烟雾对肺泡结构和分子维持程序的破坏与肺气肿的发病机制有关。目前的应用集中在环境压力，如香烟烟雾（CS）和污染物引起的激活“变阻器”分子的概念，这些变阻器分子控制有害的肺泡间隔细胞反应，包括氧化应激、细胞凋亡和肺泡炎症。根据这一总体模式，我们提出了针对细胞应激反应基因RTP801的机制研究，RTP801是在对缺氧诱导因子-1a （HIF-a）上调的基因筛选中发现的，并被证明可以诱导氧化应激和细胞凋亡。RTP801灭活了mTORC1（哺乳动物雷帕霉素复合物1的靶点），它控制着作为环境应激生理分子传感器的中枢细胞信号通路。因此，mTORC整合了生长因子信号、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，抑制肺泡细胞mTOR信号，导致肺泡细胞炎症和凋亡。RTP801的上调引起氧化应激触发的动力蛋白轻链分子8的释放。B和NF-?B活化。我们的初步数据表明，RTP801基因敲除小鼠对香烟引起的肺部炎症、细胞凋亡和肺气肿具有保护作用。特异性目的1将证明应激反应基因RTP801是香烟引起的小鼠肺气肿所必需的。Specific Aim 2将证明rtp801通过抑制其下游靶点mTOR介导香烟烟雾诱导的肺部炎症和凋亡。特异性Aim3将证明RTP801对mTOR信号的抑制导致氧化应激依赖性的动力蛋白轻链分子8 （LC8）从I？B，导致NF-?B的活化。这些目标依赖于翻译和综合方法，包括敲除和转基因小鼠，体内和体外操纵RTP801/mTOR/AKT基因表达和信号传导，腺相关病毒或腺病毒基因转导，siRNA或短发夹RNA，针对mTOR和氧化应激的补充药物干预，以及详细的形态学和肺泡损伤的细胞评估。我们的研究提出了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。这种由RTP801介导的相互作用可能构成先天免疫和获得性免疫以及生长因子的细胞保护的关键调节剂，这是肺气肿发病机制的核心。