Epithelial JNK-TGFb1 Signaling Axis in Airway Remodeling

气道重塑中的上皮 JNK-TGFb1 信号轴

• 批准号: 7367482
• 负责人: Yvonne M. W. Janssen-Heininger
• 金额: $ 37.63万
• 依托单位: UNIVERSITY OF VERMONT & ST AGRIC COLLEGE
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2012-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7367482
• 关键词: Activins; Address; Alleles; Allergic; Antigens; Applications Grants; Attenuated; Automobile Driving; Biochemical; Bleomycin; Breathing; Causations; Cell Line; Cicatrix; Collagen; Complex; Cultured Cells; Data; Dependence; Deposition; Development; Dimerization; Dominant-Negative Mutation; E-Cadherin; End Point; Enterobacteria phage P1 Cre recombinase; Environment; Epithelial; Epithelial Cells; Epithelium; Evaluation; Event; Facility Construction Funding Category; Fibroblasts; Fibronectins; Fibrosis; Gene Expression; Gene Proteins; Gene Targeting; Genes; Human; Human Cell Line; In Vitro; Inflammation; JUN gene; Knock-out; Laboratories; Lead; Link; Lung; MADH2 gene; MADH3 gene; MADH4 gene; MAPK8 gene; Measures; Mediating; Mediator of activation protein; Mesenchymal; Modeling; Molecular; Molecular Target; Mus; Other Finding; Outcome; Ovalbumin; Pathway interactions; Personal Satisfaction; Phosphorylation; Phosphotransferases; Play; Primary Cell Cultures; Process; Production; Proline; Proteins; Publishing; Refractory; Relative (related person); Resistance; Respiratory physiology; Role; Serine; Signal Pathway; Signal Transduction; Site; Smooth Muscle Actin Staining Method; Source; Structure of parenchyma of lung; TGF-beta type I receptor; Testing; Transcription Factor AP-1; Transcriptional Activation; Transgenic Mice; Tube; airway epithelium; airway hyperresponsiveness; airway remodeling; allergic airway disease; attenuation; base; cell type; cytokine; epithelial to mesenchymal transition; fibrogenesis; human TGFB1 protein; improved; in vivo; insight; mouse model; mutant; novel; novel therapeutics; protein expression; receptor; response; stress-activated protein kinase 1

DESCRIPTION (provided by applicant): The development of fibrosis represents a critical parameter of airway remodeling, and likely is the outcome of numerous signaling cascades operative in different cell types. The pro-fibrotic cytokine, transforming growth factor beta-1 (TGF-1) plays a cardinal role in the development of fibrosis, and the outcome of TGF-1 induced signaling is highly dependent upon the cellular environment, and the cooperation with other signaling pathways. Exciting new preliminary studies from our laboratory have identified a critical role for c-Jun-N- terminal-kinase (JNK) in augmenting the pro-fibrotic effects of TGF-1, in association with the causation of a mesenchymal transition of airway epithelial cells (EMT). We have demonstrated that; 1) JNK is predominantly activated in airway epithelium from ovalbumin sensitized and challenged mice; 2) Mice lacking JNK1 (JNK1-/-) fail to induce mesenchymal genes or develop fibrosis in response to ovalbumin challenge or TGF-1, or bleomycin administration; 3) Primary tracheal epithelial cells derived from JNK1-/- mice are refractory to TGF-1-induced expression of mesenchymal genes and proteins; and 4) TGF-1 induced epithelial-to mesenchymal transition requires JNK1. Our data, suggest a critical role of airway epithelium-derived JNK- dependent signals in orchestrating airways fibrosis. The hypothesis of this proposal is that activation of JNK1 in the airway epithelium is required for the development of subepithelial fibrosis in murine models of airway remodeling by promoting epithelial to mesenchymal transition (EMT). We hypothesize that JNK1 enhances TGF-1 signaling, via coordinated linker phosphorylation of receptor SMADs, and phosphorylation of c-Jun, resulting in enhanced expression of mesenchymal genes, critical to TGF-1-induced fibrosis. In Specific Aim #1, we will determine the requirement for JNK1 in TGF-1-induced epithelial to mesenchymal transition in primary cultures of tracheal epithelial cells. In Specific Aim #2, we will determine whether increases in mesenchymal gene expression in airway epithelium, and development of subepithelial fibrosis in mice require a JNK1-TGF- signaling axis. Specific Aim #3 proposes to elucidate the relative importance of JNK1- dependent phosphorylation of c-Jun or rSMADs linker regions in augmenting TGF-1 induced signaling, whereas Specific Aim #4 will unravel whether JNK1 activation, c-Jun and SMAD3 linker phosphorylation, and subsequent c-Jun and SMAD4 dependent transcriptional responses within the airway epithelium are critical in the orchestration of OVA or TGF-1-induced airways fibrosis. The outcome of our study, which is based on cell culture and genetically altered mouse models, will provide a better understanding of the molecular signals that lead to collagen deposition (scarring) of airways, and the relevance of epithelial cells in this process. Project Narrative: Epithelial cells that line the airways (breathing tubes) are now well known to play a critical role in the defense against inhaled materials, and are important in maintaining normal lung function. However, our laboratories have identified that epithelial cells play a negative role in promoting stiffening of the lung tissue, thereby decreasing lung function. We have identified some critical biochemical signals that promote this possibly negative event. Project Narrative: This grant proposal has four specific aims to test the importance of these biochemical signals in lung stiffening, and will use primary cell cultures from mouse airways, a human epithelial cell line, and the construction of genetically altered mice. Completion of this project will provide new insights into the process of lung stiffening, and may lead to the development of new therapeutics to limit lung stiffening, and also potentially reverse this process.

描述（由申请人提供）：纤维化的发展代表了气道重塑的关键参数，并且可能是在不同细胞类型中起作用的众多信号级联的结果。促纤维化细胞因子转化生长因子β-1（transforming growth factor beta-1，TGF-1）在纤维化的发展中起着重要作用，并且TGF-1诱导的信号传导的结果高度依赖于细胞环境以及与其他信号传导途径的合作。来自我们实验室的令人兴奋的新的初步研究已经确定了c-Jun-N-末端激酶（JNK）在增强TGF-1的促纤维化作用中的关键作用，其与气道上皮细胞（EMT）的间充质转化的原因相关。我们已经证明，1）JNK主要在来自卵清蛋白致敏和激发的小鼠的气道上皮中被激活; 2）缺乏JNK 1（JNK 1-/-）的小鼠不能诱导间充质基因或响应于卵清蛋白激发或TGF-1或博来霉素施用而发生纤维化; 3）来源于JNK 1-/-小鼠的原代气管上皮细胞对TGF-1诱导的间充质基因和蛋白质的表达不敏感; TGF-1诱导的上皮细胞向间充质细胞转化需要JNK 1。我们的数据表明气道上皮来源的JNK依赖性信号在协调气道纤维化中的关键作用。该建议的假设是，气道上皮中JNK 1的活化是通过促进上皮向间质转化（EMT）而在气道重塑的鼠模型中上皮下纤维化的发展所需的。我们假设JNK 1通过受体SMADs的协调连接磷酸化和c-Jun的磷酸化增强TGF-1信号传导，导致间充质基因的表达增强，这对TGF-1诱导的纤维化至关重要。在具体目标#1中，我们将确定在气管上皮细胞的原代培养物中TGF-1诱导的上皮向间充质转化中对JNK 1的需求。在具体目标#2中，我们将确定小鼠气道上皮中间充质基因表达的增加和上皮下纤维化的发展是否需要JNK 1-TGF-信号传导轴。具体目标#3提出阐明c-Jun或rSMAD接头区的JNK 1依赖性磷酸化在增强TGF-1诱导的信号传导中的相对重要性，而具体目标#4将阐明JNK 1活化、c-Jun和SMAD 3接头磷酸化，以及随后的c-Jun和SMAD 4依赖的气道上皮细胞内的转录反应在OVA或TGF-1的协调中是至关重要的。导致气道纤维化。我们的研究结果是基于细胞培养和基因改变的小鼠模型，将更好地理解导致气道胶原沉积（瘢痕形成）的分子信号，以及上皮细胞在这一过程中的相关性。项目叙述：现在众所周知，排列在气道（呼吸管）上的上皮细胞在防御吸入物质方面起着关键作用，并且在维持正常肺功能方面很重要。然而，我们的实验室已经确定，上皮细胞在促进肺组织硬化，从而降低肺功能方面起着负面作用。我们已经确定了一些关键的生化信号，促进了这一可能的负面事件。项目叙述：这项拨款提案有四个具体目标，以测试这些生化信号在肺硬化中的重要性，并将使用来自小鼠气道的原代细胞培养物，人类上皮细胞系，以及基因改造小鼠的构建。该项目的完成将为肺硬化过程提供新的见解，并可能导致新疗法的开发，以限制肺硬化，并可能逆转这一过程。