Soluble adenylyl cyclases in lung endothelial tauopathy

肺内皮tau蛋白病中的可溶性腺苷酸环化酶

基本信息

批准号：
10636060
负责人：
Troy Stevens
金额：
$ 49.68万
依托单位：
UNIVERSITY OF SOUTH ALABAMA
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-03-20 至 2027-02-28
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10636060
关键词：
Acute Lung Injury Address Adenylate Cyclase Alveolar Bacteria Bacterial Infections Bacterial Pneumonia Binding Bioenergetics Blood Blood Vessels Blood capillaries Bronchoalveolar Lavage Fluid Capillary Permeability Cells Cerebrospinal Fluid Clinical Communication Consumption Cyclic AMP Cyclic AMP-Dependent Protein Kinases Cyclic GMP Cyclic Nucleotides Data Dedications Dissociation Edema Endothelial Cells Endothelium Enzymes Functional disorder Gases Generations Homologous Gene Hydrolase Impairment Infection Interleukin-1 Receptors Knowledge Lung Mammalian Cell Membrane Microtubules Morbidity - disease rate Niacinamide Nicotinamide adenine dinucleotide Organ Patients Peripheral Permeability Phosphorylation Pneumonia Process Production Protein Kinase Pseudomonas aeruginosa Pseudomonas aeruginosa infection Recovery Role Signal Transduction Site Sterility Stimulus Structure Tauopathies Tertiary Protein Structure Testing Traction Type III Secretion System Pathway Variant Work brain parenchyma cytotoxic endothelial repair exoenzyme innate immune mechanisms lung injury lung repair metabolomics microorganism mortality mutant novel pathogen prevent repaired response tau Proteins tau-1

项目摘要

PROJECT SUMMARY/ABSTRACT The alveolar-capillary membrane facilitates efficient gas exchange while maintaining a restrictive permeability barrier. Pseudomonas aeruginosa infection disrupts the alveolar-capillary barrier leading to exudative edema and impaired oxygenation. P. aeruginosa utilizes a type III secretion system and its effectors to disrupt barrier integrity. In particular, the exoenzyme Y is introduced into lung endothelium, where it acquires nucleotidylyl cyclase activity and produces cGMP, cAMP, and cUMP. These cyclic nucleotide monophosphates activate protein kinase A resulting in endothelial tau phosphorylation, tau dissociation from microtubules, and microtubule breakdown, which collectively hinders repair following infection. Phosphorylated tau is released from endothelium as cytotoxic variants that contribute to lung injury. The signaling mechanisms used by exoenzyme Y to produce cytotoxic tau is incompletely understood, yet cUMP is produced at especially high concentrations and the cUMP signal parallels the generation of cytotoxic tau. Elevations in cUMP are sufficient to promote the production of cytotoxic tau variants. Our preliminary data demonstrate that the exoenzyme Y-induced cUMP signal also decreases endothelial nicotinamide adenine dinucleotide (NAD+) and increases nicotinamide, the product of NAD+ hydrolase activity, which may impair recovery following infection. Lung endothelium expresses sterile alpha and TIR motif containing 1 (SARM1), the only TIR (Toll/Interleukin-1 Receptor) domain protein in mammalian cells that possesses NAD+ hydrolase activity. Recent studies revealed a SARM1 bacterial homologue is directly activated by cUMP as an essential innate immune mechanism. While our studies illustrate an important role for cUMP in the endothelial cell response to infection, how exoenzyme Y generates the cUMP that leads to tau phosphorylation and production of cytotoxic tau variants, and how cUMP lowers NAD+ while hindering endothelial cell repair remains poorly understood. To address this knowledge gap in a rigorous way, this project tests the hypothesis that the P. aeruginosa exoenzyme Y generates cUMP, which contributes to the tau phosphorylation, microtubule breakdown, and SARM1-dependent NAD+ hydrolase activity that causes lung injury and hinders repair.

项目概要/摘要肺泡毛细血管膜促进有效的气体交换，同时保持限制性渗透性障碍。铜绿假单胞菌感染破坏肺泡毛细血管屏障，导致渗出性水肿和氧合作用受损。铜绿假单胞菌利用 III 型分泌系统及其效应器破坏屏障正直。特别是，外酶 Y 被引入肺内皮，在那里它获得核苷酸酰基环化酶活性并产生 cGMP、cAMP 和 cUMP。这些环核苷酸单磷酸激活蛋白激酶 A 导致内皮 tau 磷酸化、tau 从微管解离以及微管损坏，共同阻碍感染后的修复。磷酸化 tau 蛋白从内皮作为导致肺损伤的细胞毒性变异体。外酶使用的信号传导机制 Y 产生细胞毒性 tau 蛋白的机制尚不完全清楚，但 cUMP 的产生浓度特别高 cUMP 信号与细胞毒性 tau 蛋白的产生同时发生。 cUMP 的升高足以促进产生细胞毒性 tau 变体。我们的初步数据表明，外切酶 Y 诱导的 cUMP 信号还减少内皮烟酰胺腺嘌呤二核苷酸 (NAD+) 并增加烟酰胺， NAD+水解酶活性的产物，可能会损害感染后的恢复。肺内皮细胞表达包含 1 (SARM1) 的无菌 α 和 TIR 基序，这是细胞中唯一的 TIR（Toll/Interleukin-1 受体）结构域蛋白具有 NAD+ 水解酶活性的哺乳动物细胞。最近的研究揭示了一种 SARM1 细菌同源物作为一种重要的先天免疫机制被 cUMP 直接激活。虽然我们的研究表明 cUMP 在内皮细胞对感染的反应中发挥重要作用，外酶 Y 如何产生 cUMP 导致 tau 磷酸化和细胞毒性 tau 变体的产生，以及 cUMP 如何降低 NAD+，同时阻碍内皮细胞修复的机制仍知之甚少。为了以严格的方式解决这一知识差距，该项目测试了铜绿假单胞菌外切酶 Y 生成 cUMP 的假设，这有助于 tau 磷酸化、微管破坏和 SARM1 依赖性 NAD+ 水解酶活性导致肺损伤损伤并阻碍修复。