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

• 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
• 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; 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

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.

项目摘要 PI：Manu Ben-Johny博士 NAV1.5通道从根本上参与了心脏的正常功能和病理生理学。 NAV1.5 功能障碍与各种威胁生命的心脏疾病有关 心律不齐，心肌病和心力衰竭。这些病理的新兴共同点增加了 NA的晚期电流导致心脏作用电位的高原阶段中持续的NA涌入。 了解调节晚期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的药理学。我们最近的研究和初步数据 建议晚期Na电流由Na通道调节剂有力调节，称为成纤维细胞生长因子 对心肌细胞内源性的同源因子（FHF）。但是，FHF如何实现这一重要 NAV1.5的模式及其与疾病致病机制的相关性尚未完全确定。在这个 协作项目，我们寻求（1）剖析了后期NA电流的FHF调节的分子机制，并且 （2）确定该调节方案的生理和病理生理学相关性。武装 机械洞察力，我们试图设计后期Na电流的新型基于肽的抑制剂。特别是作为FHF 经历了广泛的替代替代性，我们使用 新颖的FRET分析和通过广泛的单通道分析。探测FHF的生理影响 调节晚期Na电流，我们在与长QT和Qut区别的心肌细胞中病毒操纵FHF水平 混合合成的患者衍生的诱导多能干细胞以及转基因小鼠心室 心肌细胞。在这样做的情况下，该提案承诺将新的生物物理和生理见解调节 心脏NAV1.5并告知NA通道病的可变临床表现的基础机制。