Pericyte KATP channel hyperactivity in cerebral small vessel disease

脑小血管疾病中周细胞 KATP 通道过度活跃

基本信息

批准号：
10750246
负责人：
Danielle A Jeffrey
金额：
$ 3.91万
依托单位：
UNIVERSITY OF COLORADO DENVER
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-07-16 至 2026-07-15
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10750246
关键词：
3-Dimensional Acute Agonist Arterial Disorder Arteries Blood Vessels Blood capillaries Brain Capillary Endothelial Cell Cells Cephalic Cerebral small vessel disease Cerebrovascular Circulation Cerebrovascular Disorders Cerebrum Chronic Complex Computer software DTR gene Data Dementia Deposition Diameter Disease Distal Endothelial Cells Epidermal Growth Factor Receptor Exposure to Extracellular Domain Functional disorder Genetic Glyburide Goals Hour Hyperactivity Image Immunohistochemistry Impairment Induced Mutation Ischemic Stroke Kinetics Ligands Link Literature Location Matrix Metalloproteinase Inhibitor Measures Membrane Potentials Metabolic Metabolic Diseases Microcirculation Microvascular Dysfunction Modality Modeling Morphology Mus Mutation NOTCH3 gene Nature Neurons Nutrient Paper Patients Perfusion Pericytes Physiological Pinacidil Population Potassium Preparation Production Property Proteins Publishing Reagent Receptor Aggregation Receptor Inhibition Receptor Signaling Regulation Relaxation Reporting Role Sentinel Signal Transduction Smooth Muscle Myocytes Subcortical Infarctions Subcortical Leukoencephalopathy Syndrome TIMP3 gene Techniques Testing Thinness Training Vascular Dementia Vascular Smooth Muscle Vasodilation antagonist arteriole autosome cell type comparison control electrical property experimental study extracellular genetic approach in vivo insight knock-down mouse model mutant neurovascular neurovascular coupling new therapeutic target novel parenchymal arterioles patch clamp receptor response two-photon uK-ATP-1 potassium channel

项目摘要

Project Summary Cerebral Autosomal Dominate Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is a common small vessel disease (SVD) that is characterized by microvascular dysfunction leading to ischemic stroke and vascular dementia. CADASIL is caused by mutations in the NOTCH3 gene expressed by smooth muscle cells (SMCs), that are associated with larger vasculature such as arteries/arterioles, and pericytes that wrap around capillaries. These mutations induce extracellular receptor aggregation and complex formation with other proteins including matrix metalloproteinase inhibitor, TIMP3. TIMP3 therefore accumulates around the microcirculation causing impaired cerebral blood flow (CBF) regulation. Downstream of TIMP3 accumulation, the pathomechanism includes epidermal growth factor receptor (EGFR) inhibition, resulting in decreased neurovascular coupling (NVC) and ATP production. While this pathomechanism has been investigated in other vascular cell types (endothelial cells and SMCs), pericytes remain understudied. Pericytes are an abundant, highly heterogenous population, that includes mesh pericytes which display fast on/off contractile responses and typically reside on 1-4th order capillaries. Recent studies have revealed a KATP channel, Kir6.1, is uniquely highly expressed in pericytes compared to other cells in the microvascular domain. This channel has proven to be highly relevant in CBF regulation where activation of the channel from low ATP, results in pericyte hyperpolarization, ensuing vasodilation to enhance regional cerebral perfusion to meet energy demands. Due to the CADASIL’s early presentation of neurovascular dysfunction, this proposal focuses on mesh pericytes and their impairment. My preliminary data show that, in CADASIL, mesh pericyte Kir6.1 channels are hyperactive in basal conditions, indicating dysregulation of channel activity. However further characterization of the channel is needed to elucidate potential treatment targets. Specifically, how TIMP3 and EGFR signaling influence Kir6.1 channel activity. This proposal’s first Aim is to characterize Kir6.1 channel properties using a bimodal approach looking at both function and expression in cerebral mesh pericytes. The goal of the second Aim is to expose the mechanism underlying Kir6.1 channel dysfunction including TIMP3 exogenous application and genetic knockdown. This Aim will also employ rescue techniques via EGFR ligand, HB-EGF, to restore Kir6.1 channel function, which due to its prominent expression in cerebral pericytes may be key to restoring CBF dysregulation in CADASIL. Completion of this proposal will fill a significant gap in the literature involving cerebral mesh pericytes and the devastating cerebrovascular disease, CADASIL which currently has no cure and limited treatment options.

项目概要伴有皮质下梗塞和白质脑病的常染色体主导性脑动脉病 (CADASIL) 是一种常见小血管病（SVD），其特征是微血管功能障碍导致缺血中风和血管性痴呆是由平滑肌细胞表达的 NOTCH3 基因突变引起的。肌肉细胞 (SMC)，与较大的脉管系统（如动脉/小动脉）和周细胞相关这些突变诱导细胞外受体聚集并形成复合物。因此，其他蛋白质（包括基质金属蛋白酶抑制剂 TIMP3）在 TIMP3 周围积聚。微循环导致 TIMP3 积累的下游脑血流 (CBF) 调节受损。其病理机制包括表皮生长因子受体 (EGFR) 抑制，导致神经血管耦合 (NVC) 和 ATP 产生，而这种病理机制已在其他方面进行了研究。血管细胞类型（内皮细胞和 SMC）、周细胞仍处于研究不足状态。周细胞是一个丰富的、高度异质的群体，其中包括显示速度快的网状周细胞开/关收缩反应，通常驻留在 1-4 级毛细血管上。最近的研究揭示了 KATP。与微血管域中的其他细胞相比，Kir6.1 通道在周细胞中独特地高表达。该通道已被证明与 CBF 调节高度相关，其中低 ATP 激活通道，导致周细胞超极化，随后血管舒张，增强局部脑灌注以满足能量需求由于 CADASIL 早期表现出神经血管功能障碍，因此该提案重点关注网格。周细胞及其损伤。我的初步数据表明，在 CADASIL 中，网状周细胞 Kir6.1 通道在基础条件下过度活跃，表明通道活动失调，但是需要进一步表征通道。具体来说，阐明潜在的治疗靶标，TIMP3 和 EGFR 信号传导如何影响 Kir6.1 通道。该提案的第一个目标是使用双峰方法来表征 Kir6.1 通道属性。第二个目标是揭示脑网状周细胞的功能和表达。 Kir6.1通道功能障碍的机制包括TIMP3外源应用和遗传该目标还将采用通过 EGFR 配体 HB-EGF 的救援技术来恢复 Kir6.1 通道。功能，由于其在大脑周细胞中的突出表达，可能是恢复 CBF 失调的关键该提案的完成将填补涉及脑网的文献的重大空白。周细胞和破坏性脑血管疾病 CADASIL 目前无法治愈且有限治疗方案。