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.

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