Endothelial Piezo1 channel and cerebral blood flow control

内皮Piezo1通道与脑血流控制

• 批准号: 10719633
• 负责人: Osama F Harraz
• 金额: $ 59.32万
• 依托单位: UNIVERSITY OF VERMONT & ST AGRIC COLLEGE
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2028-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10719633
• 关键词: Acceleration; Address; Affect; African American population; Angiotensin II; Animals; Blood Vessels; Blood capillaries; Blood flow; Brain; Brain region; Capillary Endothelial Cell; Cardiovascular Diseases; Cations; Cells; Cerebrovascular Circulation; Cerebrovascular system; Characteristics; Chronic; Coupled; Cues; Data; Deceleration; Disease; Electrophysiology (science); Endothelial Cells; Endothelium; Engineering; Feedback; Foundations; Friction; Future; Genetic; Genetic Engineering; Genetically Engineered Mouse; Goals; Health; High Prevalence; Human; Hyperemia; Hypertension; Image; Interoception; Kinetics; Knock-out; Knockout Mice; Laser-Doppler Flowmetry; Lasers; Learning; Measurement; Measures; Mechanics; Mediating; Membrane Potentials; Memory; Metabolic; Monitor; Mus; Mutation; Neurons; Nitric Oxide; Outcome; Peripheral; Piezo 1 ion channel; Population; Positioning Attribute; Probability; Production; Proteins; Regional Blood Flow; Regulation; Relaxation; Reporting; Research; Risk Factors; Shapes; Signal Transduction; Stimulus; System; Testing; Transgenic Mice; Translating; United States National Institutes of Health; Vasodilator Agents; Vibrissae; Work; arteriole; behavior test; blood pressure regulation; brain endothelial cell; brain health; cerebral capillary; cerebrovascular; clinically relevant; druggable target; experience; fluorescence imaging; gain of function; gain of function mutation; hemodynamics; hypertensive; improved; in vivo; interest; mechanical drive; mechanical force; mechanical stimulus; mouse model; neural; neurotransmission; neurovascular coupling; new therapeutic target; novel; pharmacologic; prevent; response; shear stress; spatiotemporal; time use; two photon microscopy; two-photon

Project Summary/Abstract: Cerebral blood flow (CBF) is precisely controlled to satisfy neuronal metabolic demands. Active neurons signal to the vasculature via multiple neurovascular coupling mechanisms to increase regional blood flow in a phenomenon known as functional hyperemia (FH). The hyperemic response increases the frictional forces imposed by blood flow onto endothelial cells (ECs) of arterioles and capillaries. We have recently demonstrated that the Piezo1 channel is a crucial mechanosensor in brain capillary ECs, and that it mediates Ca2+ signals in response to mechanical stimuli. However, the impact of Piezo1 signaling on CBF control remains unknown. In response to the NIH Notice of Special Interest (NOT-AT-21-002) “Promoting Research on Interoception and Its Impact on Health and Disease,” we provide compelling preliminary evidence that Piezo1-mediated interoception is crucial in CBF regulation, and that this mechanism is compromised during hypertension. Building on our preliminary data, we aim to test the overarching hypothesis that cerebrovascular Piezo1 regulates CBF at the local capillary level and at the large-scale level in extended brain regions. Aim 1 will employ EC-specific genetically encoded Ca2+ indicator mice, widefield and two-photon fluorescence imaging to determine the spatial, temporal, and spread characteristics of Piezo1-mediated Ca2+ transients in brain capillaries. Moreover, we will use genetic and pharmacological approaches to determine if Ca2+ signaling mediated by Piezo1 is coupled to the production of the potent vasodilator nitric oxide to increase local capillary blood flow. In Aim 2, we will determine how large-scale Piezo1 activation during FH triggers a cationic conductance, which dampens hyperpolarization-mediated FH, much like a built-in brake system. To achieve this goal, we will use genetically engineered mice with reduced Piezo1 activity in all ECs or brain ECs, along with near infrared laser imaging, and laser doppler flowmetry. In Aim 3, we will determine if cerebrovascular Piezo1 signaling is compromised in hypertension and whether a Piezo1 channelopathy-like effect leads ultimately to CBF deficits. We will directly measure Piezo1 channel activity and CBF in two mouse models of hypertension and in genetically engineered transgenic mice that harbor a human Piezo1 mutation. Use of this mutation is clinically relevant, in that PIEZO1 mutations are prevalent in African Americans, a population with the highest prevalence of hypertension worldwide. Completion of this project will support the concept that Piezo1 is crucial in CBF regulation, and that alteration of its activity is a novel risk factor for CBF decline. This work will further provide new therapeutic targets for improving CBF in cardiovascular disease.

项目摘要/摘要： 精确控制脑血流量（CBF）以满足神经元代谢需求。活跃的神经元信号 通过多种神经血管耦合机制进入脉管系统，以增加局部血流量 现象称为功能性充血（FH）。充血反应增加摩擦力 由血流施加到小动脉和毛细血管的内皮细胞（EC）上。我们最近展示了 Piezo1 通道是脑毛细血管内皮细胞中至关重要的机械传感器，并且它介导 Ca2+ 信号 对机械刺激的反应。然而，Piezo1 信号传导对 CBF 控制的影响仍不清楚。在 对 NIH 特别关注通知 (NOT-AT-21-002)“促进内感受及其研究”的回应 对健康和疾病的影响”，我们提供了令人信服的初步证据，证明 Piezo1 介导的内感受 在 CBF 调节中至关重要，并且这种机制在高血压期间会受到损害。建立在我们的 初步数据，我们的目的是测试脑血管 Piezo1 调节 CBF 的总体假设 局部毛细血管水平和扩展大脑区域的大规模水平。目标 1 将采用 EC 特定的 基因编码的 Ca2+ 指示小鼠，宽场和双光子荧光成像以确定空间， 脑毛细血管中 Piezo1 介导的 Ca2+ 瞬变的时间和传播特征。此外，我们将 使用遗传和药理学方法来确定 Piezo1 介导的 Ca2+ 信号是否与 产生强效血管扩张剂一氧化氮，以增加局部毛细血管血流量。在目标 2 中，我们将 确定 FH 期间大规模 Piezo1 激活如何触发阳离子电导，从而抑制 超极化介导的跳频，很像内置制动系统。为了实现这一目标，我们将利用基因 工程小鼠的所有 EC 或大脑 EC 中的 Piezo1 活性均降低，并进行近红外激光成像， 和激光多普勒血流计。在目标 3 中，我们将确定脑血管 Piezo1 信号传导是否受到损害 高血压以及 Piezo1 通道病样效应是否最终导致 CBF 缺陷。我们将直接 测量两种高血压小鼠模型和基因工程小鼠中的 Piezo1 通道活性和 CBF 携带人类 Piezo1 突变的转基因小鼠。这种突变的使用具有临床相关性，因为 PIEZO1 突变在非裔美国人中普遍存在，这是高血压患病率最高的人群 全世界。该项目的完成将支持 Piezo1 在 CBF 调节中至关重要的概念，并且 其活性的改变是 CBF 下降的一个新的危险因素。这项工作将进一步提供新的治疗靶点 改善心血管疾病的 CBF。