The Unfolded Protein Response in Human Airway and Alveolar Epithelial Cells

人类气道和肺泡上皮细胞中未折叠的蛋白质反应

基本信息

批准号：
7837633
负责人：
SALIM MERALI
金额：
$ 7.5万
依托单位：
TEMPLE UNIV OF THE COMMONWEALTH
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-05-11 至 2012-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7837633
关键词：
Alveolar Anti-Inflammatory Agents Anti-inflammatory Antioxidants Apoptosis Apoptotic Biochemical Pathway Biological Calnexin Cell Death Cells Chronic Chronic Obstructive Airway Disease Cigarette Cigarette Smoker Data Development Disease Endoplasmic Reticulum Epithelial Cells Erythroid Fibrosis GRP78 gene Gene Expression Gold Harvest Homeostasis Human In Situ In Vitro Individual Lasers Lectin Lung Lung Inflammation Lung diseases Metaplasia Microscopy Molecular Chaperones NF-E2-related factor 2 Nuclear Oxidants Pathogenesis Phosphotransferases Predisposition Protein Disulfide Isomerase Proteins Pulmonary Emphysema Research Risk Factors Signal Pathway Signal Transduction Smoke Smoker Staging Stream Structure of parenchyma of lung Techniques Testing Tissue Sample Tissues Up-Regulation Work abstracting activating transcription factor 4 base calreticulin cell type cigarette smoke-induced cigarette smoking cigarette smoking common cellular transcription factor ATF endoplasmic reticulum stress improved novel oxidant stress prevent protein kinase R public health relevance response transcription factor transcription factor CHOP

项目摘要

DESCRIPTION (provided by applicant): Cigarette smoking induced chronic obstructive pulmonary disease (COPD) is characterized by alveolar epithelial cell death and airway metaplasia and fibrosis. We have shown that the lungs of chronic cigarette smokers without COPD manifest a compensatory response to endoplasmic reticulum stress termed the unfolded protein response (UPR) and that the UPR-related transcription factors, ATF-4 and Nrf2, proteins which regulate anti-oxidant gene expression, are up-regulated by CS in cultured airway epithelial cells. These data raise the possibility that the UPR protects lung cells against oxidant stress and the development of COPD. However, when ER stress is sufficiently severe and protein homeostasis cannot be restored, the UPR causes apoptosis by up-regulating expression of the pro-apoptotic transcription factor, CHOP. These latter observations raise the alternative possibility that the UPR may contribute to the pathogenesis of emphysema by inducing cell apoptosis. Our previous studies were performed in whole lung lysates and cultured airway epithelial cells. We have not studied the in situ response of specific lung cell types to cigarette smoke exposure. Accordingly, the specific Aim of this 2 year project is to characterize the UPR induced by cigarette smoke in a lung cell involved in the pathogenesis of COPD, i.e., airway epithelial cells. We will test the hypotheses that UPR response to cigarette smoke is impaired in the airway epithelial cells of subjects with COPD. Expression of the UPR hallmark proteins (i.e., GRP78, calreticulin, calnexin and protein disulfide isomerase), oxidant defense (i.e., Nrf2 and ATF4) and apoptosis (i.e., CHOP) will be compared in airway epithelial cells from subjects with and without COPD. Cells will be harvested from ex-- smokers without COPD (n=10) and ex-smokers with COPD in GOLD stages II (n=10) and IV (n=10) using the technique of laser capture microscopy applied to HOPE fixed, inflated lung tissue sections. A better understanding of the cellular basis of the UPR induced by CS should enhance our understanding of the pathogenesis of COPD. PUBLIC HEALTH RELEVANCE: Cigarette smoking is a risk factor for chronic obstructive pulmonary disease (COPD), a disease characterized by inflammation, and lung cell death. However, the pathogenesis of this disease remains incompletely understood and current therapies are inadequate. Our recent work shows that a novel biochemical pathway induced in the lung by cigarette smoking can be protective. This response and its biological consequences will be studied in cell type known to be involved with COPD. The results obtained are expected to improve our understanding of cigarette smoke-related lung disease and contribute to the development of new and better treatments. (End of Abstract)

描述（由申请人提供）：吸烟诱发的慢性阻塞性肺疾病（COPD）的特点是肺泡上皮细胞死亡和气道化生和纤维化。我们已经证明，没有慢性阻塞性肺病的慢性吸烟者的肺部表现出对内质网应激的代偿性反应，称为未折叠蛋白反应（UPR），并且 UPR 相关转录因子 ATF-4 和 Nrf2（调节抗氧化基因的蛋白质）在培养的气道上皮细胞中，CS 上调表达。这些数据提出了 UPR 保护肺细胞免受氧化应激和 COPD 发展的可能性。然而，当 ER 应激足够严重并且蛋白质稳态无法恢复时，UPR 通过上调促凋亡转录因子 CHOP 的表达来引起细胞凋亡。后面的这些观察结果提出了另一种可能性，即 UPR 可能通过诱导细胞凋亡而促进肺气肿的发病机制。我们之前的研究是在全肺裂解物和培养的气道上皮细胞中进行的。我们尚未研究特定肺细胞类型对香烟烟雾暴露的原位反应。因此，这个为期两年的项目的具体目标是表征香烟烟雾在参与 COPD 发病机制的肺细胞（即气道上皮细胞）中诱导的 UPR。我们将测试 COPD 受试者气道上皮细胞对香烟烟雾的 UPR 反应受损的假设。将比较患有和不患有 COPD 的受试者的气道上皮细胞中 UPR 标志蛋白（即 GRP78、钙网蛋白、钙连接蛋白和蛋白质二硫键异构酶）、氧化防御（即 Nrf2 和 ATF4）和细胞凋亡（即 CHOP）的表达。使用适用于 HOPE 固定、膨胀的肺组织切片。更好地了解 CS 诱导的 UPR 的细胞基础应该可以增强我们对 COPD 发病机制的理解。公共卫生相关性：吸烟是慢性阻塞性肺病 (COPD) 的危险因素，慢性阻塞性肺病是一种以炎症和肺细胞死亡为特征的疾病。然而，这种疾病的发病机制仍不完全清楚，目前的治疗方法也不足。我们最近的工作表明，吸烟在肺部诱导的一种新的生化途径可以起到保护作用。这种反应及其生物学后果将在已知与慢性阻塞性肺病有关的细胞类型中进行研究。所获得的结果预计将提高我们对与香烟烟雾相关的肺部疾病的了解，并有助于开发新的更好的治疗方法。（摘要完）