Intrapulmonary itaconate as a host-protective metabolite during ER Stress and Klebsiella pneumoniae infection

肺内衣康酸作为内质网应激和肺炎克雷伯菌感染期间宿主保护性代谢物

基本信息

批准号：
10600071
负责人：
Tomeka L Suber
金额：
$ 16.07万
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：
2022
资助国家：
美国
起止时间：
2022-04-01 至 2027-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10600071
关键词：
Aconitic Acid Acute Acute Lung Injury Address Affect Alveolar Macrophages Antibiotic Resistance Bacteria Basic Science Biology Bleomycin Bone Marrow Carboxy-Lyases Cell Death Cell Line Cell Survival Cells Cellular Stress Cellular biology Chimera organism Citric Acid Cycle Clinical Critical Care Critical Illness Development Plans Elderly Enzymes Epithelial Cells Equilibrium Exhibits Experimental Models Exposure to Fibroblasts Focal Infection Foundations Goals Gram-Negative Bacteria Hospitalization Host Defense Host Defense Mechanism Human Immune Immunocompromised Host Immunophenotyping In Vitro Infection Inflammation Inflammatory Response Injury Intensive Care Units Interferon Type I K-Series Research Career Programs Klebsiella pneumoniae Knockout Mice Knowledge Lipopolysaccharides Lower Respiratory Tract Infection Lung Lung infections Macrophage Mediator Medicine Mentors Mentorship Metabolic Metabolism Mitochondria Modeling Multi-Drug Resistance Mus Myelogenous Myeloid Cells Nosocomial pneumonia Outcome Pathway interactions Patients Physicians Pneumonia Population Predisposition Prevalence Production Proliferating Proteins Publishing Pulmonary Fibrosis Regulation Research Research Personnel Resolution Role Scientist Sepsis Single Nucleotide Polymorphism Slice Small Interfering RNA Source Specificity Structure of parenchyma of lung Syndrome Systemic disease Techniques Testing Tissues Training Translational Research Work alveolar epithelium biological adaptation to stress career development cell injury conditional knockout cytokine defense response effective therapy endoplasmic reticulum stress epithelial injury improved improved outcome in vivo in vivo Model interest knock-down metabolomics monocyte mortality mouse model multidisciplinary novel pathogen patient population pneumonia model programs resilience resistant Klebsiella pneumoniae response skills stressor success targeted treatment therapy design therapy development tissue injury tool transcriptomics wound healing

项目摘要

PROJECT ABSTRACT Gram negative bacteria are the most common pathogens implicated in nosocomial pneumonia in critically ill patients. Klebsiella pneumoniae (KP) in particular has grown in prominence worldwide with increasing prevalence of antibiotic resistance, hypervirulent strains, and invasive clinical syndromes. Mechanisms of host defense responsible for effective clearance of KP infection from the lung in susceptible hosts are still unclear. Cis-aconitate decarboxylase 1 (Acod1) is a mitochondrial enzyme robustly induced in murine and human alveolar macrophages that catalyzes the production of itaconate. Itaconate suppresses inflammatory responses through a proposed Nrf2-dependent mechanism. The goal of this proposal is to define the role of myeloid-derived itaconate in pulmonary host defense during KP infection and to determine how it confers protection from local tissue injury. In a murine model of pneumonia using KP as the pathogen, we have shown that Acod1 deficiency is associated with decreased survival and increased bacterial dissemination. We have also shown that itaconate depletion reduces expression of key proteins of the cellular integrated stress response (ISR) pathway during ER stress, suggesting that it may regulate this pathway. Our proposal will address the following specific aims: 1) To determine if myeloid cell-derived itaconate limits local KP infection and protects against extrapulmonary sepsis; and 2) To determine whether itaconate is host-protective through the ISR and decreases cellular injury during KP infection. We hypothesize that Acod1, and thus itaconate production, is protective against sepsis and associated tissue injury in this model and increases host resilience. We also anticipate that macrophage-derived itaconate increases protection from ER stress both in macrophages and lung epithelial cells in vitro and in vivo. These studies will utilize in vitro and translational tools including an in vivo intrapulmonary KP infection model using wild-type and Acod1-/- mice, bone marrow chimeras, RAW 264.7 macrophage cell lines (wild-type and Acod1-/-), human and mouse precision-cut lung tissue slices, and human alveolar macrophages to address our research questions. In addition, we will perform transcriptomic and metabolomic profiling across affected tissues during disseminated KP infection, immunophenotype myeloid subsets, and execute complementary cell biology studies to examine key targets of the integrated stress response pathway in the presence or absence of itaconate in myeloid and epithelial cells. This work will elucidate novel immune mechanisms that may be exploited to reduce mortality associated with this pathogen. The proposal incorporates a strong mentorship team led by Dr. Janet Lee as Director of the Acute Lung Injury Center of Excellence and a robust career development plan. Support of this proposal with a K08 Career Development Award will establish a foundation for success and independence for the candidate as a physician-scientist in pulmonary and critical care medicine.

项目摘要革兰氏阴性细菌是危及肺炎的最常见病原体患者。尤其是肺炎克雷伯氏菌（KP）随着全球的突出性增长抗生素耐药性，高呼吸菌株和侵入性临床综合征的患病率。宿主的机制尚不清楚负责有效清除肺部肺部KP感染KP感染的防御。顺式 - 脱羧酶1（ACOD1）是一种在鼠和人牙槽中鲁棒诱导的线粒体酶催化Itaconate产生的巨噬细胞。 Itaconate通过提出的NRF2依赖机制。该提议的目的是定义髓样衍生的作用 KP感染期间肺部宿主防御中的Itaconate，并确定其如何赋予局部保护组织损伤。在使用KP作为病原体的肺炎的鼠模型中，我们表明ACOD1缺乏症与生存降低和细菌传播增加有关。我们还表明了Itaconate 耗竭降低了ER期间细胞整合应力反应（ISR）途径的关键蛋白的表达压力，表明它可以调节这一途径。我们的建议将解决以下具体目标：1）确定髓样细胞衍生的Itaconate是否限制了局部KP感染并防止肺外败血症； 2）确定Itaconate是否通过ISR进行宿主保护并减少细胞损伤 KP感染。我们假设Acod1及其产量是针对败血症和在该模型中相关的组织损伤并提高宿主的弹性。我们还期望巨噬细胞衍生 Itaconate在体外和体内增加了巨噬细胞和肺上皮细胞中的ER胁迫的保护。这些研究将利用体外和翻译工具，包括体内肺内KP感染模型使用野生型和ACOD1 - / - 小鼠，骨髓嵌合体，RAW 264.7巨噬细胞系（野生型和 ACOD1 - / - ），人和小鼠精确切割肺组织切片以及人肺泡巨噬细胞来解决我们的研究问题。此外，我们将在受影响的组织中进行转录组和代谢组分析在传播KP感染期间研究在存在或不存在Itaconate的情况下检查集成应力响应途径的关键目标在髓样和上皮细胞中。这项工作将阐明可以利用的新型免疫机制降低与这种病原体相关的死亡率。该提案结合了由博士博士领导的强大指导团队。珍妮特·李（Janet Lee）是急性肺部损伤卓越中心和强大的职业发展计划的主任。获得K08职业发展奖的该提案的支持将为成功建立基础候选人是肺和重症监护医学的医师科学家的独立性。