MiR-181b, endothelial cells, and vascular inflammation

MiR-181b、内皮细胞和血管炎症

• 批准号: 8345479
• 负责人: MARK W FEINBERG
• 金额: $ 42.27万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-01 至 2017-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8345479
• 关键词: 3' Untranslated Regions; Acute; Adhesions; Adhesives; Anti-Inflammatory Agents; Anti-inflammatory; Atherosclerosis; Base Pairing; Binding; Bioluminescence; Blood Vessels; CX3CL1 gene; Cell Adhesion Molecules; Cell Communication; Cell physiology; Cellular biology; Characteristics; Chronic; Deletion Mutation; Disease; Disease Progression; E-Selectin; Endothelial Cells; Foundations; Functional RNA; Functional disorder; Gene Expression; Gene Targeting; Goals; Homeostasis; Human; Hyperlipidemia; Immune response; Importins; Inflammation; Inflammation Mediators; Inflammatory; Inflammatory Response; Lead; Lesion; Leukocyte Rolling; Leukocytes; Link; Mediating; Mediator of activation protein; Messenger RNA; MicroRNAs; Molecular; Morbidity - disease rate; Mus; Myocardial Infarction; NF-kappa B; Nuclear Translocation; PTGS2 gene; Pathway interactions; Patients; Peripheral Vascular Diseases; Physiological; Plasma; Plasminogen Activator Inhibitor 1; Process; Property; Proteins; RNA; Regulation; Reporter Genes; Risk Factors; Role; Signal Transduction; Societies; Stimulus; Stroke; TNF gene; Thrombosis; Tissue Sample; Tissues; Vascular Cell Adhesion Molecule-1; Vascular Endothelium; acute coronary syndrome; atherogenesis; atherothrombosis; base; cell type; chemokine; cytokine; in vivo; insight; intravenous administration; intravital microscopy; leukocyte activation; loss of function; molecular imaging; monolayer; mortality; novel; novel therapeutic intervention; overexpression; response; vascular inflammation

DESCRIPTION (provided by applicant): Endothelial cell (EC) activation and dysfunction have been linked to a variety of vascular inflammatory disease states including atherosclerosis-the major cause of morbidity and mortality in Western Societies. Accumulating studies highlight a critical role for enhanced NF-kB pathway activation in atherosclerotic tissues including the vascular endothelium. Proinflammatory cytokines and proatherogenic risk factors such as hyperlipidemia lead to NF-kB activation, an effect that confers pro-adhesive, pro-thrombotic properties to ECs. Therefore, suppressing the inflammatory response in the vascular endothelium may provide a novel therapeutic approach to limit atherothrombosis. MicroRNAs (miRNAs) are small, single-stranded, non-coding RNAs capable of repressing gene expression by base pairing to the 3' untranslated regions (3'-UTRs) of mRNA targets and are involved in a variety of pathophysiological processes including the regulation of immune and inflammatory responses. However, the role of microRNAs in atherosclerotic-associated endothelial activation remains poorly defined. We undertook a microarray profiling approach in endothelial cells (ECs) and identified that miR-181b expression is rapidly reduced in response to TNF-a and in the vascular endothelium from atherosclerotic-prone mice - observations that are recapitulated in human inflammatory paradigms in vivo. Based on our preliminary studies, we find that miR-181b overexpression inhibited TNF-a-induced NF-kB-responsive targets including adhesion molecules (e.g. VCAM-1, E-selectin), chemokines (e.g. CX3CL1, CXCL1), and proinflammatory mediators (e.g. COX-2, PAI-1) that are critical to lesion formation, composition, or pre-disposition to thrombosis. Gain and loss-of function studies reveal that miR-181b potently inhibited leukocyte adhesion to endothelial monolayers, whereas inhibition of miR-181b had the opposite effect. Mechanistically, we find that MiR-181b suppressed the activation of the NF-?B pathway by binding uniquely to the 3'UTR of importin-a3, a protein involved in the nuclear translocation of NF-?B, and reduced its expression. Finally, systemic intravenous administration of miR-181b mimics reduced EC activation and leukocyte accumulation in vivo. These observations provide the foundation for the central hypothesis that miR-181b may serve as a critical regulator of EC activation and vascular homeostasis. To better understand the precise role of miR-181b in NF-kB signaling and EC activation, three aims are proposed. In Aim1, we will delineate the upstream mechanisms governing miR-181b expression in ECs. In Aim 2, we will determine the molecular basis for miR-181b's ability to regulate NF-kB signaling and EC activation. In Aim 3, we will explore the effect of altered miR-181b expression on acute and chronic vascular inflammation. The results of these studies will provide insights regarding miR-181b function in EC biology, vascular inflammation, and atherothrombosis and may provide new targets for anti-inflammatory therapy. PUBLIC HEALTH RELEVANCE: The activation of the vascular endothelium is a characteristic feature seen in atherosclerosis and other chronic inflammatory diseases, an effect that may promote disease progression leading to heart attack, stroke, or peripheral vascular disease. We have identified a novel microRNA, termed miR- 181b, that is rapidly reduced in response to pro-inflammatory cytokines in endothelial cells and our studies indicate that miR-181b may act to dampen vascular inflammation within the vessel wall. The proposed studies will provide a detailed understanding underlying the function of this factor with the goal of developing novel therapies for the treatment of acute and chronic inflammatory disease.

描述（由申请人提供）：内皮细胞（EC）激活和功能障碍与各种血管炎性疾病状态有关，包括动脉粥样硬化 - 西方社会发病和死亡率的主要原因。累积研究强调了在包括血管内皮在内的动脉粥样硬化组织中增强NF-KB途径激活的关键作用。促炎性细胞因子和促孕激素危险因素（例如高脂血症）导致NF-KB激活，这种作用赋予了ECS的亲粘连，亲栓性特性。因此，抑制血管内皮中的炎症反应可能会提供一种新型的治疗方法来限制动脉粥样硬化。 microRNA（miRNA）是小的，单链的非编码RNA，能够通过基础配对抑制基因表达的mRNA靶标的3'未翻译区域（3'-UTRS），并且参与了多种病理生理过程，包括调节免疫和炎症反应。然而，microRNA在动脉粥样硬化相关的内皮激活中的作用仍然很差。我们在内皮细胞（EC）中进行了一种微阵列分析方法，并确定MiR-181b表达响应于TNF-A和来自动脉粥样硬化的易启发的小鼠的血管内皮而迅速降低，这些观察值是在体内炎症范式中被追溯到的。基于我们的初步研究，我们发现miR-181b过表达抑制了TNF-A诱导的NF-KB响应性靶标，包括粘附分子（例如VCAM-1，E-选择蛋白），趋化因子，趋化因子，CX3CL1，CXCL1，CXCL1，以及对E.G. cox.g. cox。组成或血栓形成前置置。功能丧失研究表明，miR-181b有效抑制白细胞对内皮单层的粘附，而miR-181b的抑制作用具有相反的作用。从机械上讲，我们发现miR-181b通过独特地结合了Importin-A3的3'UTR，这是一种参与NF-？b的核转运并降低其表达的蛋白，从而抑制了NF-？B途径的激活。最后，全身静脉注射miR-181b模拟于体内的EC激活和白细胞的积累降低。这些观察结果为中心假设奠定了基础，即miR-181b可以作为EC激活和血管稳态的关键调节剂。为了更好地了解miR-181b在NF-KB信号传导和EC激活中的确切作用，提出了三个目标。在AIM1中，我们将描述有关ECS中miR-181b表达的上游机制。在AIM 2中，我们将确定miR-181b调节NF-KB信号传导和EC激活能力的分子基础。在AIM 3中，我们将探讨MIR-181B表达改变对急性和慢性血管炎症的影响。这些研究的结果将提供有关MiR-181b在EC生物学，血管炎症和动脉粥样硬化中的功能的见解，并可能为抗炎疗法提供新的靶标。 公共卫生相关性：血管内皮的激活是动脉粥样硬化和其他慢性炎症性疾病中看到的特征，这种作用可能促进疾病进展，从而导致心脏病发作，中风或周围血管疾病。我们已经鉴定出一种称为miR-181b的新型microRNA，该microRNA对内皮细胞中促炎性细胞因子的响应迅速降低，我们的研究表明，miR-181b可能作用于减轻血管内血管炎症的作用。拟议的研究将提供对该因素功能的详细理解，目的是开发用于治疗急性和慢性炎症性疾病的新型疗法。