The Impact of miR-21 Expression on Endothelial Cell Apoptosis and Inflammation

miR-21表达对内皮细胞凋亡和炎症的影响

• 批准号: 7931520
• 负责人: CHARLES D SEARLES
• 金额: --
• 依托单位: VETERANS HEALTH ADMINISTRATION
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-10-01 至 2014-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7931520
• 关键词: Address; Adhesions; Anti-Inflammatory Agents; Anti-inflammatory; Antiatherogenic; Aorta; Apoptosis; Apoptotic; Arterial Fatty Streak; Atherosclerosis; Biological Process; Blood Vessels; Blood flow; Brain; Cell Adhesion Molecules; Cell physiology; Cells; Cellular Morphology; Cellular biology; Coronary; Data; Development; Diabetes Mellitus; Differentiation and Growth; Disease; Endothelial Cells; Etiology; Gene Expression; Gene Targeting; Genes; Heart Diseases; Hematopoietic; Hour; Human; Hypertension; Inflammation; Inflammatory; Inhibition of Apoptosis; Intercellular adhesion molecule 1; Knowledge; Mediating; MicroRNAs; Molecular; Molecular Biology; Morbidity - disease rate; Morphogenesis; PTEN gene; Pathway interactions; Pattern; Phenotype; Play; Population; Process; Regulation; Relative (related person); Research; Risk Factors; Role; Signal Pathway; Signal Transduction; Skeletal Muscle; Smoking; Stimulus; Testing; Trees; Untranslated RNA; Vascular Diseases; Vascular remodeling; Veterans; angiogenesis; atheroprotective; cardiogenesis; gene function; gene interaction; hypercholesterolemia; in vivo; insight; member; migration; monocyte; mortality; mouse model; research study; response; shear stress; therapeutic target; tumorigenesis

DESCRIPTION (provided by applicant): Project Summary 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 posttranscriptionally 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 the most highly regulated miRNA, miR-21, will be studied. Specifically, the proposed experiments will define the impact of miR-21-target gene interaction on shear stress-induced changes in apoptosis and inflammatory molecule expression. Studies will be performed on cultured human endothelial cells subjected to unidirectional and oscillatory shear stress. The activity of apoptotic or inflammation signaling pathways containing miR-21 target genes, such as PI3K/Akt and MAP2K3, will be assessed. Pathway involvement will be tested by experimentally manipulating expression of miR-21, 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 and adhesion molecule expression will be quantified. Finally, the interaction between miR-21 expression and apoptotic or inflammatory pathway activity 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 largest cause of mortality in the U.S and a major cause of morbidity and mortality among the nation's veteran population. 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 a newly identified class of regulatory molecules, known as microRNAs, modulate vascular gene expression and function in response to flow. Findings from this project will provide insight into new potential therapeutic targets.

描述（由申请人提供）： 本提案的目的是确定microRNA表达对内皮细胞功能响应剪切力的特定变化的影响。由血流产生的剪切应力在调节血管张力、血管重构和动脉粥样硬化病变的局灶性发展中起重要作用。在动脉树中，内皮细胞暴露于不同的剪切应力，其诱导对基因表达和功能的不同影响。单向剪切应力，发生在树的直的部分，elevening内皮基因表达的变化，通常是抗炎和动脉粥样硬化保护。相反，在动脉树中的分支点处发生的振荡剪切应力诱导总体促炎和促动脉粥样硬化反应。微小RNA（miRNA）是最近公认的一类短（19-25 nt）、单链、非编码RNA，它们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、增殖和细胞凋亡。虽然已经证明了miRNA表达在各种生物学过程中的重要作用，包括心脏发生和血管生成，但目前关于特定miRNA在内皮细胞生物学中作用的数据有限。在人内皮细胞经受长时间单向剪切应力（24小时，15达因/cm 2）的初步研究中，鉴定了一组miRNA，其表达响应于该刺激而显著上调，表明这些miRNA在调节内皮细胞中的基因表达和功能中是重要的。为了进一步确定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，将研究最高度调节的miRNA miR-21的功能。具体而言，拟议的实验将确定miR-21-靶基因相互作用对剪切应力诱导的细胞凋亡和炎症分子表达变化的影响。研究将在单向和振荡剪切应力下培养的人内皮细胞上进行。将评估含有miR-21靶基因（如PI 3 K/Akt和MAP 2K 3）的细胞凋亡或炎症信号传导途径的活性。将通过实验操作miR-21、其靶基因或miRNA-靶基因相互作用下游的通路成员的表达来测试通路参与。随后，将量化这些操作对内皮细胞凋亡和粘附分子表达的影响。最后，将在体内研究miR-21表达与细胞凋亡或炎症途径活性之间的相互作用，在改变主动脉血流的小鼠模型中。我们预计，这些研究将有助于解决我们对内皮细胞中miRNA功能的认识不足，并将增强我们对剪切应力调节血管疾病的机制的理解。 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，是美国最大的死亡原因，也是美国退伍军人发病和死亡的主要原因。虽然动脉粥样硬化的病因与危险因素有关，如糖尿病、高血压、高胆固醇血症和吸烟，但炎症过程优先发生在与低血流和受干扰血流相关的动脉区域，而不影响未受干扰的血流区域，表明血流模式对疾病过程至关重要。该项目的目的是研究一种新发现的调节分子（称为microRNA）调节血管基因表达和功能以响应流量的机制。该项目的发现将为新的潜在治疗靶点提供深入了解。