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: 8162633
• 负责人: CHARLES D SEARLES
• 金额: $ 32.28万
• 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 2015-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8162633
• 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. PUBLIC HEALTH RELEVANCE: Coronary atherosclerotic heart disease is an inflammatory disease that is the greatest cause of mortality in the U.S. Although the etiology of atherosclerosis is related to risk factors, such as diabetes, hypertension, hypercholesterolemia, and smoking, the inflammatory process occurs preferentially in arterial regions associated with low and disturbed blood flow while sparing the undisturbed flow regions, indicating that blood flow patterns are essential to the disease process. The purpose of this project is to examine the mechanisms by which an important new class of regulatory molecules, known as microRNAs, modulate vascular gene expression and function in response to flow.

描述（由申请人提供）：本提案的目的是确定 microRNA 表达对响应剪切应力而发生的内皮细胞功能特定变化的影响。血流产生的剪切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发挥着重要作用。在动脉树中，内皮细胞受到不同的剪切应力，这会对基因表达和功能产生不同的影响。发生在树的笔直部分的单向剪切应力会引起内皮基因表达的变化，这种变化通常具有抗炎和动脉粥样硬化的作用。相反，发生在动脉树分支点的振荡剪切应力会诱导整体促炎和促动脉粥样硬化反应。 MicroRNA (miRNA) 是最近公认的一类短 (19-25 nt)、单链非编码 RNA，已成为分子生物学研究的主要焦点，因为它们在转录后调节参与一系列细胞功能的基因的表达，包括分化、生长、增殖和凋亡。尽管已经证明 miRNA 表达对各种生物过程（包括心脏发生和血管生成）具有重要作用，但目前有关特定 miRNA 在内皮细胞生物学中的作用的数据有限。在对人类内皮细胞进行长时间单向剪切应力（24小时，15达因/厘米2）的初步研究中，鉴定出一组miRNA，其表达在这种刺激下显着上调，表明这些miRNA在调节基因表达方面很重要和内皮细胞的功能。为了进一步明确 miRNA 表达在调节剪切应力诱导的内皮细胞生物学变化中的作用，将研究一种高度剪切响应的 miRNA miR-155 的功能。具体来说，拟议的研究将确定 miR-155 与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 调节细胞凋亡的机制，我们将重点关注 SHIP1/PI3K/Akt 通路。为了研究 miR-155 调节内皮单层通透性和迁移的机制，我们将重点关注 RhoA/Rho 激酶通路。我们将通过实验操纵 miR-155、其靶基因或 miRNA-靶基因相互作用下游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，将在主动脉血流改变的小鼠模型中体内研究剪切诱导的 miR-155 表达与内皮细胞调节途径活性之间的关联。我们预计这些研究将有助于解决我们对内皮细胞中 miRNA 功能的了解不足，并将增强我们对剪切应力调节血管疾病机制的理解。 公共卫生相关性：冠状动脉粥样硬化性心脏病是一种炎症性疾病，是美国死亡的最大原因。虽然动脉粥样硬化的病因与糖尿病、高血压、高胆固醇血症和吸烟等危险因素有关，但炎症过程优先发生在动脉区域与低血流和血流紊乱相关，同时保留未受干扰的血流区域，这表明血流模式对于疾病过程至关重要。该项目的目的是研究一类重要的新型调节分子（称为 microRNA）调节血管基因表达和响应血流功能的机制。