Mechanism-inspired Strategies to Prevent Pathogenic Late Na Current in Cardiac Arrhythmias

预防心律失常致病性晚钠电流的机制启发策略

基本信息

批准号：
10587033
负责人：
Manu Ben Johny
金额：
$ 57.58万
依托单位：
COLUMBIA UNIVERSITY HEALTH SCIENCES
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：
2023-02-17 至 2026-11-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10587033
关键词：
Action Potentials Adult Alternative Splicing Amino Acids Arrhythmia Binding Sites Biological Assay Biophysics Cardiac Cardiac Myocytes Cardiomyopathies Cells Clinical Closure by clamp Data Disease Dizziness Doctor of Philosophy Engineering Etiology Exhibits Fibroblast Growth Factor Fibroblasts Fluorescence Resonance Energy Transfer Functional disorder Future Heart Heart Diseases Heart failure Homeostasis Human Kinetics Life Link Long QT Syndrome Maps Measurement Molecular Morphology Muscle Cells Mutagenesis Mutation Names Optics Pathogenicity Pathology Patients Penetration Peptides Pharmacology Phase Phenotype Phosphorylation Physiological Physiology Post-Translational Protein Processing Protein Isoforms Proteins RNA Splicing Regulation Rodent Role Scheme Specificity Syndrome System Therapeutic Transgenic Mice Variant Ventricular Viral clinically relevant effectiveness evaluation fluorescence imaging heart function induced pluripotent stem cell induced pluripotent stem cell derived cardiomyocytes inhibitor insight novel preservation prevent protective factors stem voltage

项目摘要

PROJECT SUMMARY PI: Manu Ben-Johny, Ph.D. NaV1.5 channels are fundamentally involved in the normal function and pathophysiology of the heart. NaV1.5 dysfunction is linked to a variety of life-threatening cardiac diseases, including congenital and acquired cardiac arrhythmias, cardiomyopathies, and heart failure. An emerging commonality for these pathologies is increased late Na current, that results in sustained Na influx during the plateau phase of the cardiac action potential. Understanding mechanisms that regulate late Na current is pivotal to understanding NaV1.5 dysfunction in cardiac pathophysiology and for developing long-sought pharmacology. Our recent studies and preliminary data suggest that late Na current is powerfully tuned by a Na channel modulator named fibroblast growth factor homologous factor (FHF) that is endogenous to cardiomyocytes. Yet, how FHF accomplishes this important mode of NaV1.5 regulation and its relevance to disease pathogenic mechanisms is not fully determined. In this collaborative project, we seek (1) to dissect the molecular mechanism of FHF regulation of late Na current, and (2) to identify the physiological and pathophysiological relevance of this modulatory scheme. Armed with in depth mechanistic insights, we seek to engineer novel peptide-based inhibitors of late Na current. In particular, as FHF undergoes extensive alternative-splicing, we evaluate isoform-specificity of late Na current regulation using a novel FRET assay and through extensive single-channel analysis. To probe the physiological impact of FHF regulation of late Na current, we virally manipulate FHF levels in cardiomyocytes differentiated from long-QT and mixed-syndrome patient-derived induced pluripotent stem cells as well as transgenic mouse ventricular myocytes. In so doing, this proposal promises new biophysical and physiological insights into modulation of cardiac NaV1.5 and inform upon mechanisms underlying variable clinical manifestations of Na channelopathies.

项目概要 PI：Manu Ben-Johny 博士 NaV1.5 通道从根本上参与心脏的正常功能和病理生理学。钠V1.5 功能障碍与多种危及生命的心脏病有关，包括先天性和获得性心脏病心律失常、心肌病和心力衰竭。这些病症的新出现的共性有所增加晚期 Na 电流，导致心脏动作电位平台期持续 Na 流入。了解调节晚期 Na 电流的机制对于理解 NaV1.5 功能障碍至关重要心脏病理生理学和开发长期寻求的药理学。我们最近的研究和初步数据表明晚期 Na 电流由称为成纤维细胞生长因子的 Na 通道调节剂强力调节心肌细胞内源性同源因子（FHF）。然而，FHF 如何实现这一重要目标 NaV1.5的调节模式及其与疾病致病机制的相关性尚未完全确定。在这个合作项目，我们寻求（1）剖析FHF调节晚Na电流的分子机制，以及 (2)确定该调节方案的生理学和病理生理学相关性。深度武装基于机制的见解，我们寻求设计新型的基于肽的晚Na电流抑制剂。特别是，作为 FHF 经历广泛的选择性剪接，我们使用新颖的 FRET 测定并通过广泛的单通道分析。探讨 FHF 的生理影响通过调节晚Na电流，我们通过病毒方式操纵从长QT和分化而来的心肌细胞中的FHF水平混合综合征患者来源的诱导多能干细胞以及转基因小鼠心室肌细胞。通过这样做，该提案有望对调节的新的生物物理和生理学见解心脏 NaV1.5 并了解 Na 离子通道病不同临床表现的潜在机制。