DCAF7/HDAC4/TFEB axis in acute lung injury

DCAF7/HDAC4/TFEB 轴在急性肺损伤中的作用

基本信息

批准号：
10183301
负责人：
Yuan Liu
金额：
$ 47.17万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-08-01 至 2023-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10183301
关键词：
Acute Acute Lung Injury Adrenal Cortex Hormones Adult Respiratory Distress Syndrome Alveolar Attenuated Autophagocytosis Bacteria Bacterial Infections Behavior Bioenergetics Biogenesis Cell Death Cell Nucleus Cells Data Defect Disease Dose Energy Supply Epithelial Epithelial Cells Equilibrium Exhibits FDA approved Functional disorder HDAC4 gene Half-Life Histone Deacetylase Inhibitor Homeostasis Housekeeping Hypoxemia Immune Immunity Impairment Inflammasome Inflammation Inflammatory Inflammatory Response Injury Innate Immune System Libraries Link Lung Lung Inflammation Lysosomes Mass Spectrum Analysis Mechanical ventilation Mediating Mitochondria Mitochondrial DNA Modality Modeling Molecular Natural Immunity Oxygen Oxygen Consumption Pathway interactions Patients Pattern Peptide Hydrolases Permeability Pharmaceutical Preparations Pneumonia Process Proteins Proteomics Reactive Oxygen Species Resolution Role Scheme Severities Signal Transduction Stress Structure of parenchyma of lung Testing Therapeutic Transcription Coactivator Work airway epithelium alveolar epithelium base cytokine cytokine release syndrome improved inhibitor/antagonist knock-down mitochondrial dysfunction molecular modeling mortality new therapeutic target novel overexpression pathogen preservation prevent protein degradation receptor recruit screening small molecule targeted treatment therapeutic development transcription factor ubiquitin-protein ligase

项目摘要

ABSTRACT Acute Respiratory Distress Syndrome (ARDS) or Acute Lung Injury (ALI) is an acute lung inflammatory process that is associated with an overall mortality ranging from 35% to 50%, and pneumonia is one of the most frequent causes. The central pathophysiology of ARDS/ALI is injury to the epithelium in the airway/alveoli, and overproduction of inflammatory factors in lung tissue. Mitochondria provide the energy supply for numerous cellular activities, and are also the powerhouses of immunity. Bacterial infection impairs mitochondria, and dysfunctional mitochondria need to be cleared through lysosomal degradation, a process termed autophagy/mitophagy. Endogenous damage-associated molecular patterns DAMPs (mtDNA, ATP, ROS) released from damaged mitochondria activate inflammasomes and inflammation. We identify that the deficiency of TFEB, a master transcription factor of autophagy and lysosome biogenesis, impairs mitophagy leading to deleterious DAMP and pro-inflammatory cytokines release, thus activating inflammasomes and inflammation. Through screening a library of FDA-approved drugs (1068 drugs), we identify that the HDAC inhibitor Panobinostat elevates TFEB protein abundance by inhibiting HDAC4. Through unbiased proteomic mass spectrometry analysis, we identify DCAF7 as a substrate receptor for CRL4 ubiquitin E3 ligase recruiting TFEB. DCAF7 overexpression dose-dependently decreases TFEB protein abundance. DCAF7 knockdown prolongs TFEB protein half-life and accumulates its protein levels in the nucleus. Specifically, our preliminary data suggest that 1) bacterial infection decreases TFEB protein levels; 2) TFEB deficiency aggravates harmful DAMP and cytokine release that in turn postpone inflammation resolution; 3) Panobinostat-mediated HDAC4 inhibition preserves TFEB proteins and alleviates bacteria-induced lung inflammation; 4) CRL4 ubiquitin E3 ligase subunit DCAF7 recruits TFEB for proteasomal degradation; 5) a novel small molecule DCAF7 inhibitor BC1753 protects TFEB against degradation. These data led to our hypothesis that inhibiting DCAF7/HDAC4 axis to prevent TFEB from degradation will attenuate bacterial infection-induced lung inflammation and improve inflammation resolution. We will conduct mechanistic studies to determine if TFEB exerts an essential role in bacterial lung inflammation through inhibiting necroptosis (Aim 1). We will examine the role of HDAC4 in regulating TFEB protein stability and lung inflammatory responses in experimental ALI models (Aim 2). We will also test if the small molecule DCAF7 inhibitor alleviates bacterial lung inflammation through preventing TFEB protein degradation (Aim 3). This will be the first study to intervene DCAF7/HDAC4/TFEB axis for inflammatory disease such as ARDS/ALI. Execution of this project will lay the groundwork for a fundamental, paradigm-changing therapeutic advance to regulate innate immunity and treat lung inflammation that will ultimately set the stage for a new translational initiative.

抽象的急性呼吸窘迫综合征 (ARDS) 或急性肺损伤 (ALI) 是一种急性肺部疾病与 35% 至 50% 的总体死亡率相关的炎症过程，以及肺炎是最常见的原因之一。 ARDS/ALI 的核心病理生理学是气道/肺泡上皮损伤以及肺部炎症因子过度产生组织。线粒体为许多细胞活动提供能量供应，也是免疫力的强国。细菌感染会损害线粒体，导致功能失调线粒体需要通过溶酶体降解来清除，这一过程称为自噬/线粒体自噬。内源性损伤相关分子模式 DAMP（mtDNA、受损线粒体释放的 ATP、ROS）会激活炎症小体和炎症。我们发现，自噬的主要转录因子 TFEB 的缺乏和溶酶体生物发生，损害线粒体自噬，导致有害的 DAMP 和促炎症细胞因子释放，从而激活炎症小体和炎症。通过筛选一个在 FDA 批准的药物库（1068 种药物）中，我们确定 HDAC 抑制剂 Panobinostat 通过抑制 HDAC4 提高 TFEB 蛋白丰度。通过公正的蛋白质组质量光谱分析，我们确定 DCAF7 是 CRL4 泛素 E3 连接酶的底物受体招募 TFEB。 DCAF7 过表达剂量依赖性地降低 TFEB 蛋白丰度。 DCAF7 敲低可延长 TFEB 蛋白半衰期并在细胞中积累其蛋白水平核。具体来说，我们的初步数据表明 1) 细菌感染会降低 TFEB 蛋白质水平； 2) TFEB 缺乏会加剧有害的 DAMP 和细胞因子的释放，进而推迟炎症消退； 3) 帕比司他介导的 HDAC4 抑制可保留 TFEB 蛋白质并减轻细菌引起的肺部炎症； 4) CRL4泛素E3连接酶亚基 DCAF7 招募 TFEB 进行蛋白酶体降解； 5）新型小分子DCAF7抑制剂 BC1753 保护 TFEB 免遭降解。这些数据得出我们的假设：抑制 DCAF7/HDAC4 轴防止 TFEB 降解，从而减弱细菌感染引起的肺部炎症并改善炎症消退。我们将进行机理研究确定 TFEB 是否通过抑制在细菌性肺部炎症中发挥重要作用坏死性凋亡（目标 1）。我们将研究 HDAC4 在调节 TFEB 蛋白稳定性中的作用和实验性 ALI 模型中的肺部炎症反应（目标 2）。我们还将测试是否小分子 DCAF7 抑制剂通过预防 TFEB 减轻细菌性肺部炎症蛋白质降解（目标 3）。这将是第一个干预 DCAF7/HDAC4/TFEB 轴的研究用于治疗 ARDS/ALI 等炎症性疾病。该项目的实施将为调节先天免疫和治疗的根本性的、改变范式的治疗进展肺部炎症最终将为新的转化计划奠定基础。