Epithelial JNK-TGFb1 Signaling Axis in Airway Remodeling

气道重塑中的上皮 JNK-TGFb1 信号轴

• 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
• 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' 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

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（由申请人提供）：上皮下纤维化的发展代表了哮喘气道重塑的一个重要特征，并且上皮细胞的关键作用正在显现，即促纤维化细胞因子转化生长因子β-1（TGF-¿1）。 ) ) 在纤维形成中起着重要作用。 1 信号传导高度依赖于与其他信号传导途径的合作，我们最近发现 c-Jun-N-末端激酶 1 (JNK1) 在增强 TGF-¿ 1，与气道上皮细胞间质转化（EMT）相关，具体来说，我们已经证明：1）JNK主要在卵清蛋白致敏和攻击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对卵清蛋白、TGF-¿ 产生纤维化1，或博来霉素3) TGF-¿ 1 诱导的 EMT 需要 JNK1，通过连接域中 SMAD3 的 JNK1 依赖性磷酸化这些数据表明，气道上皮来源的 JNK1 依赖性信号在协调气道纤维化中发挥着关键作用。气道上皮通过促进上皮间质转化，是房尘螨诱发的气道疾病中上皮下纤维化发展所必需的(EMT)，我们勇敢地承认 JNK1 增强了 TGF-¿通过连接结构域中 SMAD3 的磷酸化产生 1 信号传导，从而增强 SMAD3 减少 let-7 microRNA (miRNA) 表达的能力。let-7 miRNA 的减少反过来会增强高迁移率组 A2 (HMGA2) 基因的表达，作为 EMT 的近端调节因子，导致上皮下胶原沉积的事件在特定目标 1 中，我们将确定 JNK1 依赖性磷酸化的重要性。连接结构域中的 SMAD3 抑制肺上皮细胞中的 let-7 microRNA (miRNA)，并随后增强高迁移率组 A2 (HMGA2) 基因。我们还将分析支气管上皮细胞中 let-7 miRNA 和 HMGA2 的表达。与对照组相比，从哮喘患者中提取，并确定哮喘和正常上皮细胞对 TGF-¿ 1 诱导 EMT，并阐明 JNK 和 SMAD3 在其中的作用。在特定目标 2 中，我们将阐明气道上皮内 JNK1 的激活是否在室内尘螨诱导的上皮间质转化、气道纤维化和气道间质转化中至关重要。改变体内的呼吸力学，并利用全身缺乏 JNK1 的小鼠，或者特别是在细支气管上皮内，以下和CRE 重组酶介导的消融在特定目标 3 中，我们将通过创建 TetOP 来确定 SMAD3 接头结构域磷酸化和由此产生的 let-7g miRNA 减少在促进上皮间质转化、气道纤维化和体内呼吸力学改变中的重要性。 -FLAG-SMAD3-EPSM小鼠，其对接头结构域中的JNK磷酸化具有抵抗力，以及TetOP-FLAG-SMAD3-野生型 (WT) 转基因小鼠作为对照，我们将评估 let-7g pre-miRNA 的递送对 HDM 诱导的重塑的影响。