MicroRNA-181b and Sepsis

MicroRNA-181b 和脓毒症

基本信息

批准号：
8944822
负责人：
Rebecca M Baron
金额：
$ 46.25万
依托单位：
BRIGHAM AND WOMEN'S HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-08-15 至 2019-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8944822
关键词：
3&apos Untranslated Regions Adhesions Adhesives Adult Respiratory Distress Syndrome Anti-Inflammatory Agents Anti-inflammatory Binding Biological Biological Assay Biological Markers Blood Vessels Bronchoalveolar Lavage Fluid Cause of Death Cell Adhesion Cell Adhesion Molecules Cell Communication Cell physiology Cessation of life Clinical Critical Illness Data Disease E-Selectin Endothelial Cells Endotoxemia Event Experimental Models Extravasation Foundations Functional disorder Gene Targeting Generations Genetic Goals Human Importins Infection Inflammation Inflammation Mediators Inflammatory Injury Laboratories Lead Leukocytes Link Lung Mediator of activation protein MicroRNAs Modeling Molecular Mus Mutation NF-kappa B NFKB Signaling Pathway Nuclear Translocation Organ Organ failure Outcome PTGS2 gene Pathogenesis Pathway interactions Patients Permeability Phosphoric Monoester Hydrolases Phosphorylation Plasma Plasminogen Activator Inhibitor 1 Production Property Proteins Proto-Oncogene Proteins c-akt Regulation Replacement Therapy Reporter Genes Resveratrol Role Sampling Sepsis Sepsis Syndrome Septic Shock Severities Signal Transduction Small Interfering RNA Stimulus Therapeutic Thrombin Thrombosis Time Tissues Tumor Necrosis Factor-alpha Untranslated RNA Untranslated Regions Vascular Cell Adhesion Molecule-1 Vascular Diseases Vascular Endothelium Vascular Permeabilities base crosslinking and immunoprecipitation sequencing cytokine endothelial dysfunction human subject improved in vivo inflammatory marker insight intravenous administration intravital microscopy lung injury monolayer mortality novel novel therapeutic intervention overexpression protective effect public health relevance response septic small molecule therapy development transcriptome sequencing vascular inflammation

项目摘要

DESCRIPTION (provided by applicant): Accumulating studies highlight a critical role for endothelial cell (EC) inflammation and dysfunction in the pathogenesis of septic shock and sepsis-induced lung injury, leading causes of death among critically ill patients. Excessive generation of pro-inflammatory mediators can lead to collateral vascular dysfunction, an effect that confers pro-adhesive, pro-permeability, and pro-thrombotic properties to ECs. Therefore, modulating these events in the vascular endothelium may provide a novel therapeutic approach to limit the sequelae of sepsis and sepsis-induced lung injury. MicroRNAs (miRNAs) are small, non-coding RNAs that suppress the expression of target genes at the post-transcriptional level and are involved in a range of biological responses. However, the role of microRNAs in sepsis-associated endothelial dysfunction remains poorly defined. Using a microarray profiling approach in ECs, we identified that miR-181b expression is rapidly reduced in the vascular endothelium from endotoxemic mice - observations that are recapitulated in human subjects with sepsis in vivo. Our studies have uncovered that miR-181b inhibits targets that control 2 key signaling pathways, NF-kB and AKT/eNOS, that govern EC adhesion, vascular permeability, and proinflammatory mediators implicated in sepsis and sepsis-induced lung injury. Preliminary functional studies in ECs reveal that miR-181b potently inhibits effects on leukocyte adhesion, EC permeability, and thrombin-induced EC inflammation. MiR-181b suppresses the activation of the NF-kB pathway uniquely in ECs by binding to the 3'UTR of importin-a3, a protein involved in NF-kB nuclear translocation in ECs and not leukocytes. In contrast, miR-181b induces eNOS-phosphorylation by directly targeting the phosphatase PHLPP2, known to inhibit AKT-phosphorylation. Finally, treatment of mice by systemic intravenous administration of miR-181b mimics as "replacement therapy" reduces endotoxemia-induced EC inflammatory markers, leukocyte accumulation, lung injury, and markedly improves survival. Thus, we hypothesize that miR-181b may serve as a critical homeostatic regulator of ECs and vascular dysfunction in sepsis and sepsis-induced lung injury. To further understand the protective role of miR-181b in sepsis, we propose: in Aim1, to delineate the proximal events during sepsis regulating miR-181b expression. In Aim2, using inflammatory stimuli including human plasma samples from patients with sepsis and sepsis-induced lung injury, we will dissect the mechanisms by which miR-181b regulates NF-kB and AKT signaling in response to EC dysfunction. In Aim3, we will explore the effect and timing of altered miR-181b expression, or its targets (using genetic, siRNA, or pharmacological approaches to importin-a3 or PHLPP2), on experimental models of sepsis and EC function in vivo. Successful completion of the proposed studies will identify significant insights regarding miR-181b function in EC inflammation, vascular leak, and microvascular thrombosis, and may provide discrete, novel targets for sepsis-induced lung injury.

描述（由适用提供）：累积研究突出了内皮细胞（EC）炎症和功能障碍在败血性休克和败血症引起的肺损伤的发病机理中的关键作用，这是重症患者死亡的主要原因。过度产生的促炎性介体会导致附带血管功能障碍，这种效果使ECS具有亲粘性，促渗透性和亲栓性特性。因此，调节血管森林中的这些事件可能会提供一种新型的热方法，以限制败血症和败血症诱导的肺损伤的后遗症。 microRNA（miRNA）是小的非编码RNA，可在转录后抑制靶基因的表达，并参与一系列生物学反应。然而，microRNA在与败血症相关的室外功能障碍中的作用仍然很差。使用EC中的微阵列分析方法，我们确定MiR -181b的表达在血管内皮中迅速降低了内毒素小鼠 - 在体内败血症受试者中概括的观察结果。我们的研究发现，miR-181b抑制了控制2个关键信号通路，NF-KB和Akt/eNOS的靶标，这些靶标控制EC粘附，血管渗透性，以及在脓毒症和SPSIS诱导的肺损伤中实施的促进介质。 ECS中的初步功能研究表明，miR-181b可能抑制对白细胞粘附，EC渗透性和凝血酶诱导的EC炎症的影响。 miR-181b通过与importin-a3的3'UTR结合，抑制了EC中NF-KB途径的激活，ECS a3的3'UTR是一种参与ECS中NF-KB核转运的蛋白质，而不是白细胞。相反，miR-181b通过直接靶向磷酸酶PHLPP2来影响eNOS磷酸化，该磷酸酶PHLPP2已知会抑制Akt磷酸化。最后，通过全身性静脉内给予miR-181b模拟“替代疗法”来治疗小鼠，可减少内毒素毒素引起的EC炎症标记，白细胞积累，肺损伤，并显着提高生存率。这就是我们假设miR-181b可能是败血症和败血症诱导的肺损伤的ECS和血管功能障碍的关键稳态调节剂。为了进一步了解miR-181b在败血症中的受保护作用，我们提出：在AIM1中，在败血症调控miR-181b表达过程中描绘了代理事件。在AIM2中，使用炎症刺激，包括败血症患者和败血症诱导的肺损伤患者的人血浆样品，我们将剖析miR-181b对EC功能障碍响应EC功能障碍的NF-KB和AKT信号传导的机制。 AIM3，我们将探讨MiR-181b表达改变的效果和时机，或其靶标（使用遗传，siRNA或药物方法对importin-A3或PHLPP2进行遗传，siRNA或药物方法），对体内败血症和EC功能的实验模型。成功完成拟议的研究将确定有关MiR-181b功能在EC注射，血管泄漏和微血管血栓形成中的重要见解，并可能为败血症诱导的肺损伤提供离散的新靶标。