Epithelial JNK-TGFb1 Signaling Axis in Airway Remodeling

气道重塑中的上皮 JNK-TGFb1 信号轴

基本信息

批准号：
8459777
负责人：
Yvonne M. W. Janssen-Heininger
金额：
$ 39.27万
依托单位：
UNIVERSITY OF VERMONT & ST AGRIC COLLEGE
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-07-01 至 2017-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8459777
关键词：
3&apos Untranslated Regions Ablation Address Alleles Allergens Antigens Asthma Binding Bleomycin Cells Cicatrix Collagen Data Deposition Development Disease Enterobacteria phage P1 Cre recombinase Epithelial Epithelial Cells Epithelium Etiology Event Fibrosis Future Genes Genetic In Vitro Lead Left Lung MADH3 gene MAPK8 gene Mediating Mediator of activation protein Mesenchymal Messenger RNA MicroRNAs Modeling Mus N-terminal Outcome Ovalbumin Patients Phosphorylation Phosphotransferases Play Predisposition Process Publishing Pyroglyphidae Refractory Repression Resistance Respiratory Mechanics Role Signal Pathway Signal Transduction Signaling Molecule Signaling Protein Therapeutic Time Transgenic Mice airway epithelium airway remodeling allergic airway disease cell type cytokine epithelial to mesenchymal transition fibrogenesis human TGFB1 protein in vivo prevent public health relevance response stress-activated protein kinase 1 tool transcription factor

项目摘要

DESCRIPTION (provided by applicant): The development of subepithelial fibrosis represents an important feature of airway remodeling in asthma, and a critical role for epithelial cells herei is emerging. The pro-fibrotic cytokine, transforming growth factor beta-1 (TGF-¿1) plays a cardinal role in fibrogenesis. The outcome of TGF-¿1 signaling is highly dependent upon cooperation with other signaling pathways. We have recently identified a critical role for c-Jun-N-terminal- kinase 1 (JNK1) in augmenting the pro-fibrotic effects of TGF-¿1, in association with the causation of a mesenchymal transition of airway epithelial cells (EMT). Specifically, 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, TGF-¿1, or bleomycin; 3) TGF-¿1-induced EMT requires JNK1, through JNK1-dependent phosphorylation of SMAD3 in the linker domain. These data, suggest a critical role of airway epithelium-derived JNK1-dependent signals in orchestrating airways fibrosis. The hypothesis addressed herein is that activation of JNK1 in the airway epithelium is required for the development of subepithelial fibrosis in house dust mite- induced airways disease by promoting epithelial-mesenchymal transition (EMT). Specifically, we hypothesize that JNK1 enhances TGF-¿1 signaling via phosphorylation of SMAD3 in the linker domain, which enhances the competency of SMAD3 to decrease expression of let-7 microRNA (miRNA). Decreases in let-7 miRNA in turn enhances expression of the high mobility group A2 (HMGA2) gene, a proximal regulator of EMT, events that lead to subepithelial collagen deposition. In Specific Aim 1 we will determine the importance of JNK1-dependent phosphorylation of SMAD3 in the linker domain in repressing let-7 microRNA (miRNA) in lung epithelial cells, and subsequent enhancement of the high mobility group A2 (HMGA2) gene. We will also analyze expression of let-7 miRNA and HMGA2 in bronchial epithelial cells derived from asthmatics, compared to controls, and determine the susceptibility of asthmatic and normal epithelial cells to TGF-¿1-induced EMT, and elucidate the role of JNK and SMAD3 therein. In Specific Aim 2 we will elucidate whether activation of JNK1 within the airway epithelium is critical in the orchestration of house dust mite-induced epithelial to mesenchymal transition, airways fibrosis, and altered respiratory mechanics in vivo, and utilize mice that globally lack JNK1, or specifically within the bronchiolar epithelium, following and CRE-recombinase mediated ablation. In Specific Aim 3 we will determine the importance of SMAD3 linker domain phosphorylation and resultant decreases of let-7g miRNA in promoting epithelial to mesenchymal transition, airways fibrosis, and altered respiratory mechanics in vivo, via the creation of TetOP-FLAG-SMAD3-EPSM mice, which are refractory to phosphorylation by JNK in the linker domain, and TetOP-FLAG-SMAD3-wild type (WT) transgenic mice, as a control. We will assess the impact of delivery of let-7g pre-miRNA on HDM-induced remodeling.

描述（通过应用程序提供）：上皮下纤维化的发展代表了气道重塑在哮喘中的重要特征，并且在这里出现了上皮细胞的关键作用。促纤维化细胞因子转化生长因子β-1（TGF-€1）在纤维发生中起着基本作用。 TGF-€1信号的结果高度取决于与其他信号通路的合作。最近，我们确定了C-Jun-N-末端 - 激酶1（JNK1）在增强TGF- - 1的促纤维化作用方面的关键作用，这与气道上皮细胞（EMT）间充质过渡的原因有关。具体而言，我们已经证明：1）JNK主要在卵巢蛋白敏感和挑战的小鼠的气道上皮中被激活； 2）缺乏JNK1（JNK1 - / - ）的小鼠无法诱导间充质基因或反应纤维蛋白，以响应卵蛋白，TGF- - 1或博来霉素； 3）TGF-¿1诱导的EMT需要JNK1，通过链接域中SMAD3的JNK1依赖性磷酸化。这些数据表明，气道上皮衍生的JNK1依赖性信号在编排气道纤维化中的关键作用。本文所述的假设是，通过促进上皮 - 间质转变（EMT）来开发呼吸道上皮中JNK1的激活是需要在房屋尘埃中的纤维化发展中上皮纤维化所引起的。 Smad3的降低let-7 microRNA（miRNA）的表达。 Let-7 miRNA的减小反过来又增强了高迁移率A2（HMGA2）基因的表达，EMT的近端调节剂，导致下地下胶原沉积的事件。在特定目的1中，我们将确定在抑制肺上皮细胞中抑制Let-7 microRNA（miRNA）和随后增强高迁移率A2 A2（HMGA2）基因的LET-7 microRNA（miRNA）时，SMAD3在接头结构域中的JNK1依赖性光磷酸化的重要性。我们还将分析与对照组相比，在源自哮喘的支气管上皮细胞中Let-7 miRNA和HMGA2的表达，并确定了哮喘和正常上皮细胞对TGF-诱导的EMT的敏感性，并阐明了JNK和SMAD3的作用。 In Specific Aim 2 we will elucidate whether activation of JNK1 within the airway epithelium is critical in the orchestration of house dust mite-induced epithelial to mesenchymal transition, airways fibrosis, and altered respiratory mechanics in vivo, and utilize mice that globally lack JNK1, or specifically within the bronchiolar epithelium, following and CRE-recombinase mediated ablation. In Specific Aim 3 we will determine the importance of SMAD3 linker domain phosphorylation and resultant declines of let-7g miRNA in promoting epithelial to mesenchymal transition, airways fibrosis, and altered respiratory mechanics in vivo, via the creation of TetOP-FLAG-SMAD3-EPSM mice, which are refractory to phosphorylation by JNK in the linker domain, and TETOP-FLAG-SMAD3野型（WT）转基因小鼠作为对照。我们将评估Let-7g前MIRNA对HDM诱导的重塑的影响。