Lipid peroxidation- and pyroptosis-induced tissue factor activation in pathogen-induced blood coagulation

病原体诱导的血液凝固中脂质过氧化和焦亡诱导的组织因子激活

基本信息

批准号：
10571353
负责人：
Shabbir Ahmed Ansari
金额：
$ 16.45万
依托单位：
BETH ISRAEL DEACONESS MEDICAL CENTER
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：
2023-04-01 至 2025-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10571353
关键词：
2019-nCoV 4 hydroxynonenal Acute myocardial infarction Adult Affect Aldehydes Apoptosis Arachidonate 15-Lipoxygenase Atherosclerosis Attenuated Bacteremia Bacterial Infections Blood coagulation CASP1 gene Caspase Cell Death Cell surface Cessation of life Coagulation Process Data Disease Disseminated Intravascular Coagulation Disulfiram Enzymes Epithelium Escherichia coli Evaluation FDA approved Functional disorder Generations Genes Host Defense Human In Vitro Infection Inflammasome Inflammatory Ischemic Stroke LOX gene Life Lipid Peroxidation Lung infections Macrophage Mediating Modeling Multiple Organ Failure Mus Myocardial Infarction Organ Pathogenicity Pathologic Pathway interactions Phase Phosphatidylserines Play Polyunsaturated Fatty Acids Positioning Attribute Process Proteins Pulmonary Embolism Reporting Resistance Role SARS-CoV-2 infection Sepsis Testing Therapeutically Targetable Thromboplastin Thrombosis Training United States Virus Diseases Work chemical genetics extracellular vesicles genetic approach human disease improved in vivo lipid metabolism monocyte mouse model new therapeutic target pathogen peroxidation prevent septic thrombotic vesicular release

项目摘要

Project Summary/Abstract Tissue factor (TF), the primary initiator of the blood coagulation cascade, is carefully regulated to prevent aberrant coagulation activation. However, pathological conditions including bacterial and viral infection induce intravascular TF expression and lead to thrombosis. As TF-induced thrombosis is a major cause of acute myocardial infarction, ischemic stroke, and pulmonary embolism, improved understanding of the mechanisms of pathological TF activation may lead to new therapeutic targets. Pyroptosis, a form of inflammatory cell death, drives TF-mediated intravascular coagulation activation in bacterial sepsis. Emerging studies also implicate inflammasome activation in SARS-CoV-2 infection, but its role in TF activation is unknown. Our preliminary studies demonstrate that SARS-CoV-2 and specifically its accessory protein ORF3A induce TF activation in a phosphatidylserine (PS)-dependent mechanism that requires TMEM16F, similar to PS-dependent TF activation in pyroptosis. In Aim 1, we will investigate whether ORF3a-induced TF activation is driven by inflammasome- mediated pyroptosis. Lipid peroxidation and its highly reactive end products such as 4-hydroxy-2-nonenal (HNE) are involved in various forms of programmed cell death including pyroptosis. However, the role of HNE, the most stable and toxic reactive aldehyde produced during lipid peroxidation, in pyroptosis-associated TF and coagulation activation is not known. Our preliminary data showed that HNE induces PS-dependent TF activation in LPS-primed macrophages and causes intravascular coagulation activation in mice. However, the complete mechanism by which HNE induces PS externalization and TF activation is not known. In Aim 2, we will use chemical genetic approaches to dissect the mechanism of HNE-induced TF activation via pyroptosis in vitro and in vivo. Although lipid peroxidation plays a central role in cell death and coagulation activation in bacterial sepsis, a therapeutically targetable enzyme responsible for the unbridled lipid peroxidation and generation of pathological levels of reactive radicals such as HNE is not known. In Aim 3, we will use genetically modified mice deficient in lipid peroxidation and HNE formation to investigate TF-dependent pathologic coagulation activation and thrombosis during sepsis. A successful completion of these studies will help delineate a common pathway involved in pathologic TF activation across varied pathogenic infections and will also help identify a specific therapeutically targetable enzyme to attenuate TF activation in disease.

项目概要/摘要组织因子 (TF) 是凝血级联的主要引发剂，经过仔细调节以防止凝血激活异常。然而，包括细菌和病毒感染在内的病理条件会导致血管内TF表达并导致血栓形成。由于 TF 诱导的血栓形成是急性血栓形成的主要原因心肌梗死、缺血性中风和肺栓塞，加深了对这些疾病机制的了解病理性 TF 激活可能会带来新的治疗靶点。焦亡，一种炎症细胞死亡形式，在细菌性脓毒症中驱动 TF 介导的血管内凝血激活。新兴研究也表明 SARS-CoV-2 感染中炎症小体的激活，但其在 TF 激活中的作用尚不清楚。我们的初步研究表明，SARS-CoV-2，特别是其辅助蛋白 ORF3A 在细胞中诱导 TF 激活需要 TMEM16F 的磷脂酰丝氨酸 (PS) 依赖性机制，类似于 PS 依赖性 TF 激活在焦亡中。在目标 1 中，我们将研究 ORF3a 诱导的 TF 激活是否由炎症小体驱动介导的细胞焦亡。脂质过氧化及其高反应性最终产物，例如 4-羟基-2-壬烯醛 (HNE) 参与各种形式的程序性细胞死亡，包括细胞焦亡。然而，HNE 的作用最脂质过氧化过程中产生的稳定且有毒的活性醛，在焦亡相关的 TF 和凝血激活作用尚不清楚。我们的初步数据表明 HNE 诱导 PS 依赖性 TF 激活存在于 LPS 引发的巨噬细胞中，并引起小鼠血管内凝血激活。然而，完整的 HNE 诱导 PS 外化和 TF 激活的机制尚不清楚。在目标 2 中，我们将使用化学遗传学方法剖析 HNE 通过体外细胞焦亡诱导 TF 激活的机制体内。尽管脂质过氧化在细菌性脓毒症的细胞死亡和凝血激活中起着核心作用，一种治疗靶向酶，负责不受限制的脂质过氧化和生成反应性自由基（例如 HNE）的病理水平尚不清楚。在目标 3 中，我们将使用转基因小鼠脂质过氧化和 HNE 形成缺陷，用于研究 TF 依赖性病理性凝血激活以及败血症期间的血栓形成。成功完成这些研究将有助于描绘出一条共同的途径参与各种病原体感染的病理性 TF 激活，也将有助于识别特定的治疗靶向酶可减弱疾病中的 TF 激活。