Modulation of Endothelial Cell Function by the Shear Stress-Responsive miR-155

剪切应力响应性 miR-155 对内皮细胞功能的调节

• 批准号: 8668133
• 负责人: CHARLES D SEARLES
• 金额: $ 31.63万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-01 至 2016-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8668133
• 关键词: Actins; Address; Adhesions; Angiotensin II Receptor; Anti-Inflammatory Agents; Anti-inflammatory; Antiatherogenic; Aorta; Apoptosis; Arterial Fatty Streak; Atherosclerosis; Biological Process; Blood Platelets; Blood Vessels; Blood flow; Brain; Cell Culture Techniques; Cell physiology; Cells; Cellular Morphology; Cellular biology; Coronary; Critical Pathways; Cytoskeleton; Data; Development; Diabetes Mellitus; Differentiation and Growth; Disease; Endothelial Cells; Etiology; Functional disorder; Gene Expression; Gene Expression Regulation; Gene Targeting; Genes; Heart Diseases; Hematopoiesis; Hematopoietic; Homeostasis; Hour; Human; Hypertension; Inflammatory; Knowledge; Leukocytes; Lymphocyte; Mediating; MicroRNAs; Modeling; Molecular; Molecular Biology; Morphogenesis; Mus; Pathway interactions; Pattern; Permeability; Phenotype; Play; Process; Production; Publishing; Regulation; Regulator Genes; Regulatory Pathway; Relative (related person); Research; Rho-associated kinase; Risk Factors; Role; Signal Pathway; Signal Transduction; Skeletal Muscle; Smoking; Smooth Muscle Myocytes; Stimulus; Testing; Trees; Umbilical vein; Untranslated RNA; Vascular Diseases; Vascular remodeling; Work; angiogenesis; atheroprotective; blood pressure regulation; cardiogenesis; cell motility; cell type; gene function; gene interaction; hypercholesterolemia; in vivo; insight; member; migration; monolayer; mortality; mouse model; myo-inositol-1 (or 4)-monophosphatase; overexpression; receptor expression; response; shear stress; tumorigenesis

DESCRIPTION (provided by applicant): The purpose of this proposal is to define the influence of microRNA expression on specific changes in endothelial cell function that occur in response to shear stress forces. Shear stress forces, generated by blood flow, play an important role in the regulation of vascular tone, vascular remodeling, and the focal development of atherosclerotic lesions. In the arterial tree, endothelial cells are exposed to different shear stress forces that induce distinct effects on gene expression and function. Unidirectional shear stress, which occurs in the straight part of the tree, elicits a change in endothelial gene expression that is generally anti-inflammatory and atheroprotective. In contrast, oscillatory shear stress, which occurs at branch points in the arterial tree, induces an overall pro-inflammatory and proatherosclerotic response. MicroRNAs (miRNAs) are a recently recognized class of short (19-25 nt), single stranded, noncoding RNAs that have become a major focus in molecular biology research because they posttranscriptional regulate the expression of genes involved in an array of cell functions, including differentiation, growth, proliferation, and apoptosis. Although an important role for miRNA expression has been demonstrated for various biological processes, including cardiogenesis and angiogenesis, data on the role of specific miRNAs in endothelial cell biology is currently limited. In preliminary studies of human endothelial cells subjected to prolonged unidirectional shear stress (24 hrs, 15 dynes/cm2), a group of miRNAs was identified whose expression was significantly upregulated in response to this stimulus, suggesting that these miRNAs are important in regulating gene expression and function in endothelial cells. To further define the role of miRNA expression in modulating shear stress-induced changes in endothelial cell biology, the function of one highly shear-responsive miRNA, miR-155, will be studied. Specifically, the proposed research will define the impact of miR-155-target gene interaction on endothelial cell apoptosis, barrier function and migration. To study the mechanism by which miR-155 modulates apoptosis, we will focus on the SHIP1/PI3K/Akt pathway. To study the mechanism by which miR-155 modulates endothelial monolayer permeability and migration, we will focus on the RhoA/Rho kinase pathway. We will test the influence of miR- 155 on these critical pathways by experimentally manipulating expression of miR-155, its target gene, or members of the pathway that are downstream of the miRNA-target gene interaction. Subsequently, the effect of these manipulations on endothelial cell apoptosis, monolayer permeability, and migration will be quantified. Finally, the association between shear-induced miR-155 expression and activity of endothelial cell regulatory pathways will be studied in vivo, in a mouse model of altered aortic flow. We anticipate that these studies will help address a deficit in our knowledge about the function of miRNAs in endothelial cells and will enhance our understanding of the mechanisms by which shear stress forces modulate vascular disease.

描述(申请人提供)：本提案的目的是确定在剪切力作用下，microRNA表达对内皮细胞功能的特定变化的影响。血流产生的剪应力在调节血管张力、血管重塑和动脉粥样硬化病变的局灶性发展中起着重要作用。在动脉树中，内皮细胞暴露在不同的剪切力下，对基因表达和功能产生不同的影响。单向剪应力发生在树的直线部分，引起内皮基因表达的变化，这通常是抗炎和动脉粥样硬化保护的。相反，发生在动脉树分支点的振荡切应力会诱导整体的促炎和动脉粥样硬化反应。MicroRNAs(MiRNAs)是最近发现的一类短小(19-25nT)、单链、非编码RNA，由于它们在转录后调节一系列细胞功能相关基因的表达，包括分化、生长、增殖和凋亡，因此已成为分子生物学研究的主要焦点。虽然已经证明miRNA的表达在包括心脏生成和血管生成在内的各种生物学过程中都发挥着重要的作用，但目前关于特定miRNA在内皮细胞生物学中的作用的数据仍然有限。在对人内皮细胞承受持续的单向剪切应力(24小时，15dynes/cm2)的初步研究中，发现了一组miRNAs，它们的表达显著上调，表明这些miRNAs在调控内皮细胞的基因表达和功能方面起着重要作用。为了进一步确定miRNA表达在调节剪切力诱导的内皮细胞生物学变化中的作用，将研究一个高度剪切响应的miRNA的功能，miR-155。具体地说，拟议的研究将确定miR-155靶基因相互作用对内皮细胞凋亡、屏障功能和迁移的影响。为了研究miR-155调控细胞凋亡的机制，我们将重点研究SHIP1/PI3K/Akt通路。为了研究miR-155调节内皮细胞单层通透性和迁移的机制，我们将重点研究RhoA/Rho激酶途径。我们将通过实验操作miR-155、其靶基因或miRNA-靶基因相互作用下游的途径成员的表达，来测试miR-155对这些关键途径的影响。随后，将量化这些操作对内皮细胞凋亡、单层通透性和迁移的影响。最后，将在体内研究剪切诱导的miR-155表达与血管内皮细胞调节通路活性之间的关系，在小鼠的主动脉血流改变的模型中。我们预计，这些研究将有助于解决我们对血管内皮细胞中miRNAs功能的认识不足，并将加强我们对剪切力调节血管疾病的机制的理解。