ROS Mechanisms in BAV Aortopathy

BAV 主动脉病中的 ROS 机制

• 批准号: 8842688
• 负责人: Thomas Gillette Gleason
• 金额: $ 51.22万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-01 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8842688
• 关键词: 3-Dimensional; Abbreviations; Age; Aneurysm; Aortic Aneurysm; Architecture; Biochemistry; Biomechanics; Blood Vessels; Caliber; Caring; Cause of Death; Cell Survival; Cells; Clinical; Collagen; Collagen Fiber; Confocal Microscopy; Congenital Abnormality; Congenital Heart Defects; Data; Detection; Development; Diagnostic; Dissection; Early Diagnosis; Ehlers-Danlos Syndrome; Elastin; Elastin Fiber; Electron Spin Resonance Spectroscopy; Enzymatic Biochemistry; Exhibits; Extracellular Matrix; Fluorescence; Generations; Genes; Goals; High Pressure Liquid Chromatography; Histology; Hospital Mortality; Human; Image; In Vitro; Individual; Knowledge; Matrix Metalloproteinases; Mediating; Microscopy; Modeling; Molecular; Morphology; Mutation; Operative Surgical Procedures; Oxidative Stress; Patients; Phenotype; Population; Property; Reactive Oxygen Species; Research; Research Design; Research Personnel; Risk; Rupture; Smooth Muscle Myocytes; Specimen; Spin Trapping; Staging; Techniques; Testing; Thoracic Aortic Aneurysm; Time; Tissue Banking; Tissue Banks; United States; adjudicate; aortic valve; ascending aorta; base; bicuspid aortic valve; biological adaptation to stress; cohort; febuxostat; improved; inhibitor/antagonist; innovation; mortality; multi-photon; novel strategies; prevent; scaffold; second harmonic; sex; tissue culture; tool

DESCRIPTION (provided by applicant): This project will test the hypothesis that reactive oxygen species (ROS) accumulation in aortic smooth muscle cells (SMCs) mediates the aortopathy in patients with bicuspid aortic valve (BAV). The interdisciplinary investigative team possesses a unique composition of expertise and has devised a novel approach to prove that ROS accumulation in BAV-ascending aortic aneurysm (TAA) specimens leads to de-differentiation of SMCs, abnormal extracellular matrix (ECM) composition and architecture and altered biomechanical strength of the aortic wall. The hypothesis is supported by the team's strong preliminary data demonstrating ROS accumulation, reduced cell viability in the presence of ROS, diminished oxidative stress responses, de- differentiation of SMCs, disrupted matrix architecture and altered biomechanical tensile and delamination strengths in the ascending aorta of BAV patients compared with tricuspid aortic valve (TAV)-TAA and non- aneurysmal patients. The innovative strategy is accomplished in a two-aim approach: 1) Define what changes in SMC phenotype, ECM composition and architecture, and biomechanical tensile and delamination strengths are associated with ROS accumulation in BAV aortopathy and 2) Prove that ROS accumulation in aortic SMCs mediates the BAV aortopathy. This study will exploit 1) the PI's extensive tissue bank of human ascending aortic specimens and primary SMCs isolated from the following patient cohorts: a) BAV-TAA compared with b) non-aneurysmal BAV, c) TAV-TAA, and d) non-aneurysmal TAV "normal"; and 2) the team's established scaffold-based 3-D tissue culture model. ROS will be evaluated using the investigators' expertise in electron paramagnetic resonance spin trapping and confocal microscopy of fluorescence-based ROS probes. Innovative assessment of ECM composition and architecture will be achieved using multi-photon microscopy with second harmonic generation to define alignment of collagen and elastin fibers, histological detection of collagen and elastin, and quantification of MMP activity. The team's pioneering techniques for studying blood vessel biomechanics will be utilized throughout the research design. This study will, for the first time, define and prove that ROS mechanisms mediate the BAV aortopathy. The results will potentiate significant long-term clinical benefits including the development of improved diagnostic tools for earlier detection and better surveillance of the BAV aortopathy and the discovery of pharmacologic therapies directed at modulation of ROS in the aortic wall to prevent aneurysm formation in BAV patients.

描述(由申请者提供)：本项目将验证这样一种假设，即在二尖瓣主动脉瓣(BAV)患者中，主动脉平滑肌细胞(SMCs)中活性氧物种(ROS)的积累介导了主动脉病变。这个跨学科的研究团队拥有独特的专业知识组成，并设计了一种新的方法来证明BAV-升主动脉瘤(TAA)标本中ROS的积聚导致SMC去分化，异常的细胞外基质(ECM)组成和结构，以及主动脉壁生物力学强度的改变。这一假说得到了该团队强有力的初步数据的支持，这些数据显示，与三尖瓣主动脉瓣(TAV)-TAA和非动脉瘤患者相比，BAV患者升主动脉中ROS积累、细胞活力降低、氧化应激反应减弱、SMC去分化、基质结构破坏以及生物力学拉伸和分层强度改变。这一创新策略是通过两个目标完成的：1)确定在BAV主动脉病变中，SMC表型、ECM成分和结构以及生物力学拉伸和分层强度的变化与ROS积聚有关；2)证明主动脉SMCs中ROS积聚介导了BAV主动脉病变。这项研究将利用1)从以下患者队列分离的人升主动脉标本和原始SMC的PI的广泛组织库：a)BAV-TAA与b)非动脉瘤BAV，c)TAV-TAA，以及d)非动脉瘤TAV“正常”；2)该团队建立的基于支架的三维组织培养模型。将利用研究人员在电子顺磁共振、自旋捕获和基于荧光的ROS探针的共聚焦显微镜方面的专业知识来评估ROS。使用多光子显微镜和二次谐波产生来确定胶原和弹性蛋白纤维的排列、胶原和弹性蛋白的组织学检测以及基质金属蛋白酶活性的量化，将实现对细胞外基质成分和结构的创新评估。 该团队研究血管生物力学的开创性技术将在整个研究设计中使用。这项研究将首次定义和证明ROS机制介导BAV大动脉病变。这些结果将加强重大的长期临床益处，包括开发改进的诊断工具以更早地发现和更好地监测BAV大动脉病变，以及发现针对调节主动脉壁ROS以防止BAV患者动脉瘤形成的药物疗法。