Endothelial Toll-Like Receptor-4 Signaling in Sepsis

脓毒症中的内皮 Toll 样受体 4 信号转导

基本信息

批准号：
7418682
负责人：
JOHN Marshall HARLAN
金额：
$ 21.56万
依托单位：
UNIVERSITY OF WASHINGTON
依托单位国家：
美国
项目类别：
财政年份：
2005
资助国家：
美国
起止时间：
2005-05-01 至 2010-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7418682
关键词：
1-Phosphatidylinositol 4-Kinase Anti-Inflammatory Agents Anti-inflammatory Apoptosis Apoptotic Bacteria Binding Blood Circulation CD14 gene CD95 Antigens Caspase Inhibitor Cause of Death Cell Adhesion Molecules Cell Survival Cessation of life Complex Condition Data Development Disease Dominant-Negative Mutation Effector Cell Endothelial Cells Family Gram-Negative Bacteria Host Defense Immune response In Vitro Inflammatory Inflammatory Response Intensive Care Units Interleukin-1 Interleukin-1 Receptors Interleukin-1 beta Leukocytes Life Ligation Lipopolysaccharides Lung MAPK8 gene Mediating Modeling Molecular Mus NF-kappa B Pathogenesis Pathway interactions Pharmaceutical Preparations Phosphatidylinositols Phosphotransferases Play Proteins Proteomics Puncture procedure Receptor Signaling Research Personnel Role Sepsis Sepsis Syndrome Signal Pathway Signal Transduction TLR4 gene TNF receptor-associated factor 6 TRAF6 gene Techniques Testing Thinking Time Toll-like receptors Transcriptional Activation Transgenes Transgenic Mice Tumor Necrosis Factor-alpha Up-Regulation activated Protein C chemokine clinically relevant cytokine in vivo insight lipopolysaccharide-binding protein macrophage man member programs receptor response toll-like receptor 4 transcription factor

项目摘要

DESCRIPTION (provided by applicant): Sepsis and sepsis syndromes are life-threatening conditions and are leading causes of death in intensive care units. Sepsis is most commonly caused by Gram-negative bacteria. Lipopolysaccharide (LPS) is an important component of the bacteria wall that contributes to the pathogenesis of sepsis. Endothelial cells (ECs) are a major target of LPS and the pro-inflammatory cytokines interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNFalpha). Lipopolysaccharide, IL- 1beta, and TNFalpha all directly activate ECs and elicit an array of EC responses, including the upregulation of cytokines, chemokines, adhesion molecules, and procoagulant proteins. Most of these pro-inflammatory responses are mediated by the transcription factor NF-KappaB, which is also important for cell survival. Endothelial cell activation is thus thought to play a critical role in the development of both host defense and the systemic inflammatory response in sepsis. Increasing evidence also indicates that EC apoptosis contributes to the pathogenesis of experimental sepsis. Indeed, it has been suggested that a significant component of the beneficial effects of activated protein C, the only approved drug for the treatment of severe sepsis in man, may be due to its anti-apoptotic effects on ECs . The cellular receptor transducing the LPS signal has been identified as Toll-like receptor(TLR)4, a member of the larger family of TLR receptors. In this proposal we will examine further the molecular mechanisms of pro-inflammatory, pro-survival, and pro-apoptotic signaling by TLR4 in EC in vitro and determine the role of EC activation and apoptosis in vivo using transgenic mice in experimental sepsis induced by cecal ligation and puncture (CLP). The specific aims are: 1) To determine the role of phosphoinositide-3 kinase (PI3-K) in EC survival following LPS/TLR4 stimulation; 2) To determine the mechanisms of LPS/TLR4-lnduced pro-apoptotic signaling in ECs; 3) To identify new components of the TLR4-induced TRAF6-signaling complex in ECs; and 4) To determine the effect of inducible, selective blockade of EC NF-KappaB activation and apoptosis on sepsis induced by CLP.

描述（由申请人提供）：败血症和败血症是威胁生命的疾病，是重症监护病房中死亡的主要原因。败血症最常见于革兰氏阴性细菌引起。脂多糖（LPS）是有助于败血症发病机理的细菌壁的重要组成部分。内皮细胞（EC）是LPS和促炎性细胞因子白介素-1beta（IL-1BETA）和肿瘤坏死因子-Alpha（TNFalpha）的主要靶标。脂多糖，IL-1BETA和TNFALPHA都直接激活EC并引起一系列EC反应，包括细胞因子，趋化因子，粘附分子和proc凝蛋白的上调。这些促炎反应中的大多数是由转录因子NF-kappab介导的，这对于细胞存活也很重要。因此，人们认为内皮细胞激活在宿主防御和脓毒症的全身炎症反应的发展中起着至关重要的作用。越来越多的证据也表明EC凋亡有助于实验性败血症的发病机理。实际上，已经提出，激活蛋白C的有益作用的重要组成部分，即唯一被批准的人类治疗严重败血症的药物，可能是由于其对EC的抗凋亡作用所致。转导LPS信号的细胞受体已被鉴定为Toll样受体（TLR）4，这是TLR受体较大家族的成员。在该提案中，我们将进一步研究TLR4在EC体外的促炎，促生存和促凋亡信号的分子机制，并确定使用转基因小鼠在体内使用EC激活和凋亡在体内在实验性脓毒症中的作用。具体目的是：1）确定磷酸肌醇3激酶（PI3-K）在LPS/TLR4刺激后的EC存活中的作用； 2）确定EC中LPS/TLR4-LNDNDD的促凋亡信号的机制； 3）确定EC中TLR4诱导的TRAF6信号复合物的新组件； 4）确定EC NF-kappab激活和凋亡对CLP诱导的败血症的诱导，选择性阻断的影响。