MiR-181b, endothelial cells, and vascular inflammation

MiR-181b、内皮细胞和血管炎症

• 批准号: 8518457
• 负责人: MARK W FEINBERG
• 金额: $ 40.24万
• 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/8518457
• 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; 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; transcriptome sequencing; 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.

描述（由申请人提供）：内皮细胞（EC）激活和功能障碍与多种血管炎性疾病状态相关，包括动脉粥样硬化-西方社会发病率和死亡率的主要原因。越来越多的研究强调了增强的NF-κ B通路激活在动脉粥样硬化组织（包括血管内皮）中的关键作用。促炎性细胞因子和致动脉粥样硬化的危险因素如高脂血症导致NF-κ B活化，这种作用赋予EC促粘附、促血栓形成特性。因此，抑制血管内皮的炎症反应可能提供一种新的治疗方法来限制动脉粥样硬化血栓形成。MicroRNA（miRNAs）是一类小的单链非编码RNA，通过与mRNA靶点的3'非翻译区（3'-UTR）碱基配对抑制基因表达，参与多种病理生理过程，包括免疫和炎症反应的调节。然而，microRNA在动脉粥样硬化相关的内皮激活中的作用仍然不清楚。我们在内皮细胞（EC）中进行了微阵列分析方法，并确定了miR-181 b表达在对TNF-α的反应中以及在动脉粥样硬化倾向小鼠的血管内皮中迅速降低-在体内人类炎症范例中重现了观察结果。基于我们的初步研究，我们发现miR-181 b过表达抑制了TNF-α诱导的NF-κ B应答靶点，包括粘附分子（例如VCAM-1、E-选择素）、趋化因子（例如CX 3CL 1、CX CL 1）和促炎介质（例如考克斯-2、派-1），它们对病变形成、组成或血栓形成的易感性至关重要。获得和丧失功能的研究表明，miR-181 b有效地抑制白细胞粘附到内皮细胞单层，而抑制miR-181 b具有相反的效果。机械上，我们发现，miR-181 b抑制NF-？B途径的独特结合的3 '非翻译区的importin-a3，蛋白参与核转位的NF-？B，并降低其表达。最后，全身静脉内施用miR-181 b模拟物减少了体内EC活化和白细胞积聚。这些观察结果为核心假设提供了基础，即miR-181 b可能是EC激活和血管稳态的关键调节因子。为了更好地理解miR-181 b在NF-κ B信号传导和EC激活中的确切作用，提出了三个目标。在Aim 1中，我们将描述在EC中调控miR-181 b表达的上游机制。在目标2中，我们将确定miR-181 b调节NF-κ B信号传导和EC活化能力的分子基础。在目标3中，我们将探索改变miR-181 b表达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-181 b在EC生物学、血管炎症和动脉粥样硬化血栓形成中的功能的见解，并可能为抗炎治疗提供新的靶点。