Network signature of low-flow endothelial dysfunction

低流量内皮功能障碍的网络特征

• 批准号: 10666476
• 负责人: MARK STEPHEN TAYLOR
• 金额: $ 38.5万
• 依托单位: UNIVERSITY OF SOUTH ALABAMA
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10666476
• 关键词: Abate; Arteries; Atherosclerosis; Blood Vessels; Blood flow; Calcium-Activated Potassium Channel; Cardiovascular Diseases; Cardiovascular system; Carotid Arteries; Cell membrane; Cessation of life; Chronic; Chronic Disease; Clinical; Complex; Coupling; Data; Development; Distal; Endoplasmic Reticulum; Endothelial Cells; Endothelium; Event; Exhibits; Feedback; Fire - disasters; Frequencies; G-Protein-Coupled Receptors; Genetic; Hemostatic function; Homeostasis; Human; Hypertension; ITPR1 gene; Image; Impairment; Inflammation; Inositol; Intervention; Island; Knockout Mice; Lead; Ligation; Liquid substance; Modeling; Molecular; Mus; Obstruction; Pathologic; Pathology; Patients; Pattern; Peripheral; Peripheral arterial disease; Permeability; Phenotype; Physiological; Play; Potassium Channel; Role; Signal Transduction; Specificity; Structure; TRP channel; Time; Tunica Intima; Vascular Diseases; Vascular remodeling; Vasodilation; confocal imaging; endothelial dysfunction; extracellular; functional loss; inorganic phosphate; mouse model; novel; novel therapeutics; preservation; prevent; receptor; response; shear stress; therapeutic target; vasoconstriction

PROJECT SUMMARY/ABSTRACT The endothelium is a crucial regulator of vascular homeostasis and endothelial dysfunction is a hallmark of cardiovascular disease. The challenge in searching for new therapies is finding early control points that prevent the shift to broad pathologic signaling profiles and disrupt the endothelial network. Employing novel imaging and analysis approaches, we have identified discrete patterns of dynamic Ca2+ signalling along the vascular intima that underlie vascular function and direct the specificity, sensitivity and intensity of prevailing vascular responses. These patterns, defined by profiles of dynamic event parameters (frequency, amplitude, duration and spatial spread), form distinct signatures along the endothelial network. The complex spectrum of endothelial Ca2+ events (from isolated brief transients to broad multicellular waves) result from positive feedback interaction between plasma membrane TRP channels (Ca2+ entry) and endoplasmic reticulum IP3Rs (Ca2+ release). Small conductance Ca2+-activated K+ channels (KCa) play a key role in this signaling by exerting Ca2+-dependent hyperpolarization and amplifying Ca2+ influx through TRP channels (particularly fluid shear stress (FSS)- activated TRPV4 channels). In flow-deprived distal arteries from patients with peripheral artery disease, the endothelium exhibits a distinctive truncated Ca2+ signature characterized by spatially restricted small amplitude transients. This anomalous Ca2+ profile appears early in a low-flow carotid ligation mouse model, giving rise to endothelial dysfunction and vascular remodelling. These low-flow adaptations involve progressive loss of endothelial KCa2.3 channels and suggest an early loss of cooperative KCa/TRPV4 action. We hypothesize that disruption of TRPV4-KCa2.3 signaling under conditions of low FSS causes a progressive, highly restricted endothelial Ca2+ signature that promotes endothelial dysfunction and vascular remodeling. Aim 1 will characterize the role of TRPV4-KCa2.3 signaling in physiologic Ca2+ signatures along the arterial endothelium. We will conduct confocal imaging (with novel high-content analysis) and employ endothelium- specific knockout mice (ecKCa2.3-/- and ecTRPV4-/-) as well as human peripheral arteries to elucidate cooperative channel impacts under differential FSS. Aim 2 will determine whether low/oscillatory FSS causes truncation of the TRPV4-KCa2.3-dependent endothelial Ca2+ signature that leads to endothelial dysfunction and vascular remodeling. We will employ a partial ligation mouse model to assess the magnitude and time course of TRPV4- KCa2.3-specific impacts on Ca2+ signaling, vasoreactivity and vascular wall thickening. Aim 3 will determine whether preservation of endothelial TRPV4-KCa2.3 Ca2+ signaling ameliorates development of functional and structural vascular changes resulting from chronic low flow. We will also assess whether interventions to preserve the Ca2+ signature directly abate pathologic impacts of low flow.

项目摘要/摘要 内皮是血管稳态和内皮功能障碍的关键调节器 心血管疾病。寻找新疗法的挑战是找到防止的早期控制点 转向广泛的病理信号传导轮廓并破坏内皮网络。采用新颖的成像和 分析方法，我们已经确定了沿血管内膜的动态Ca2+信号传导的离散模式 这是血管功能的基础，并指导流行血管反应的特异性，灵敏度和强度。 这些模式，由动态事件参数（频率，振幅，持续时间和空间）的曲线定义 传播），沿着内皮网络形成不同的签名。内皮Ca2+事件的复杂频谱 （从孤立的短暂瞬变到宽的多细胞波）是由于反馈相互作用而导致的 质膜TRP通道（CA2+进入）和内质网IP3R（Ca2+释放）。小的 电导Ca2+激活的K+通道（KCA）在此信号中起着关键作用，通过施加Ca2+依赖性 超极化并通过TRP通道扩增Ca2+涌入（尤其是流体剪应力（FSS） - 激活的TRPV4通道）。在流动性远端的远端动脉中，来自周围动脉疾病的患者 内皮表现出独特的截短的Ca2+特征，其特征在于空间限制的小幅度 瞬态。这种异常的Ca2+轮廓出现在低流量颈动脉连接鼠标模型中，从而产生 内皮功能障碍和血管重塑。这些低流量的适应涉及 内皮KCA2.3通道，并提出合作KCA/TRPV4作用的早期丧失。我们假设这一点 在低FSS条件下TRPV4-KCA2.3信号传导的破坏会导致渐进性高度 受限的内皮CA2+签名，可促进内皮功能障碍和血管重塑。 AIM 1将表征TRPV4-KCA2.3信号在沿动脉的生理CA2+签名中的作用 内皮。我们将进行共聚焦成像（通过新颖的高含量分析），并采用内皮 - 特定的敲除小鼠（ECKCA2.3 - / - 和ECTRPV4 - / - ）以及人类外周动脉以阐明合作 频道在差异FS下的影响。 AIM 2将确定低/振荡FSS是否引起截断 TRPV4-KCA2.3依赖性内皮CA2+签名导致内皮功能障碍和血管 重塑。我们将采用部分连接小鼠模型来评估TRPV4-的幅度和时间过程 KCA2.3对Ca2+信号传导，血管反应性和血管壁增厚的影响。 AIM 3将确定 保存内皮TRPV4-KCA2.3 CA2+信号传导是否可以改善功能和 慢性低流量引起的结构血管变化。我们还将评估是否保存干预措施 CA2+签名直接减轻低流量的病理影响。