Cytokines, Oxidants, Neutrophils and Lung Injury

细胞因子、氧化剂、中性粒细胞和肺损伤

• 批准号: 6732639
• 负责人: Asrar B. Malik
• 金额: $ 35.07万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-06-01 至 2007-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6732639
• 关键词: NAD(P)H dehydrogenase; biological signal transduction; cell adhesion molecules; cytokine; gene expression; guanosinetriphosphatases; in situ hybridization; inflammation; laboratory mouse; lung injury; lung ischemia /hypoxia; neutrophil; northern blottings; oxidative stress; oxidizing agents; phosphorylation; protein kinase C; respiratory oxygenation; vascular endothelium

The overall objective of the proposed studies in this renewal application (yr. 13-17) is to address the critical signaling pathways by which pro- inflammatory cytokines such as TNFalpha mediate the expression of adhesion molecule, ICAM-1, in endothelial cells and thereby induce firm neutrophil (PMN) adhesion. We have shown an important function of oxidant signaling in endothelial cells in activating transcription of ICAM-1 and also a critical role of the NADPH oxidase complex in signaling ICAM-1 expression. In addition, we have identified signaling pathways involving PKC zeta and PI3 kinase/Akt that may activate oxidant signaling via NADPH oxidase. As stable and firm ICAM-1 dependent adhesion of PMN to endothelial cells will require rapid-onset protein synthesis independent of ICAM-1 expression as well as delayed protein synthesis-dependent ICAM-1 expression, we will explore both the early course of its expression involving cell surface alterations in the constitutive ICAM-1 in endothelial cells as well as delayed expression requiring de novo protein synthesis. In the proposed studies, we will determine (1) oxidant signaling of the gp91/phox and p41/phox NADPH oxidase subunits in mediating ICAM-1 expression and PMN adhesion to endothelial cells, (2) role of PKCzeta in activating oxidant signaling, and thereby in NF-kappaB activation and ICAM-1 expression, and finally (4) role of GTPases in oxidant signaling and mediating the early-onset protein synthesis-independent component of ICAM-1 expression and PMN adhesion. Studies will utilize molecular approaches to dissect the signaling pathways as well as physiological assessments of PMN sequestration and migration in lungs as well as pulmonary microvascular permeability and edema formation. With the completion of these studies, we will advance the understanding of the mechanisms by which TNFalpha induces endothelial cell ICAM-1 expression, and thereby mediates inappropriate PMN adhesion and migration across the pulmonary microvessel barrier. We hope to define the role of oxidant signaling and the signaling pathways in mediating ICAM-1 expression, and in thereby promoting endothelial adhesivity to PMN and their migration across the vessel wall. These studies will be important in providing a better understanding of the basis of inflammatory disease states such as the adult respiratory distress syndrome (ARDS) associated with increased PMN sequestration and migration so that agents can be developed to block specific signaling pathways.

本次续展申请中拟议研究的总体目标(年)13-17)阐述了促炎症细胞因子如肿瘤坏死因子α介导内皮细胞表达黏附分子ICAM-1从而诱导中性粒细胞(PMN)牢固黏附的关键信号通路。我们发现内皮细胞中的氧化信号在激活ICAM-1转录中起着重要作用，NADPH氧化酶复合体也在ICAM-1表达中起着关键作用。此外，我们还发现了涉及PKC Zeta和PI3激酶/Akt的信号通路，这些信号通路可能通过NADPH氧化酶激活氧化剂信号。由于依赖ICAM-1的PMN与内皮细胞的稳定而牢固的黏附需要快速的蛋白质合成，而不依赖于ICAM-1的表达以及延迟的蛋白质合成依赖的ICAM-1的表达，我们将探索其表达的早期过程涉及内皮细胞内构成的ICAM-1的细胞表面变化以及延迟表达需要从头开始的蛋白质合成。在拟议的研究中，我们将确定(1)gp91/Phox和p41/Phox NADPH氧化酶亚基在介导ICAM-1表达和PMN与内皮细胞黏附中的氧化信号，(2)PKcheeta在激活氧化信号中的作用，从而在NF-kappaB激活和ICAM-1表达中的作用，以及(4)GTP酶在氧化信号和介导ICAM-1表达和PMN黏附的早期蛋白合成非依赖性成分中的作用。研究将利用分子方法来剖析信号通路，以及对PMN在肺内的隔离和迁移以及肺微血管通透性和水肿形成的生理学评估。随着这些研究的完成，我们将进一步了解肿瘤坏死因子α诱导内皮细胞ICAM-1表达的机制，从而介导PMN不适当的黏附和跨越肺微血管屏障的迁移。我们希望明确氧化剂信号和信号通路在介导ICAM-1表达中的作用，从而促进内皮与PMN的黏附和它们在血管壁上的迁移。这些研究将有助于更好地了解炎症性疾病状态的基础，如与PMN隔离和迁移增加相关的成人呼吸窘迫综合征(ARDS)，以便开发出阻断特定信号通路的药物。