Integrated System for Mechanoelectrical Studies of Cardiac Myofibroblasts

心脏肌成纤维细胞机电研究集成系统

• 批准号: 8176273
• 负责人: DANIEL H REICH
• 金额: $ 24.05万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-05 至 2013-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8176273
• 关键词: Actins; Adhesives; Advanced Development; Aleurites; Architecture; Arrhythmia; Biological Models; Calcium; Cardiac; Cell Shape; Cells; Cicatrix; Collaborations; Coupling; Cues; Development; Disease; Disease Progression; Duchenne muscular dystrophy; Electric Stimulation; Electrophysiology (science); Elements; Fibroblasts; Generations; Glaucoma; Glioma; Goals; Individual; Investigation; Joints; Laboratories; Link; Magnetism; Measurement; Measures; Mechanical Stimulation; Mechanics; Membrane; Membrane Potentials; Microfabrication; Monitor; Muscle; Myocardial Infarction; Myocardium; Myofibroblast; Nanotechnology; Pattern; Physics; Play; Polycystic Kidney Diseases; Printing; Process; Production; Proteins; Research; Research Personnel; Resolution; Role; Shapes; Signal Transduction; Source; Stress; Stress Fibers; System; Techniques; Technology; Time; Tissues; Traction; Universities; base; bone cell; cell growth; cell type; elastomeric; flexibility; innovation; insight; nanoparticle; nanowire; novel; response; sensor; tumorigenesis; voltage; voltage clamp

DESCRIPTION (provided by applicant): In diverse cell types such as muscle, fibroblasts and bone, the cells can generate contractile or traction forces while being responsive to electrophysiological and mechanical signals. Although subsets of these interactions have been studied under the themes of mechanotransduction and excitation-contraction coupling, a full understanding of the interrelationship between cell mechanics and cell electrophysiology requires the simultaneous measurement of cell force, cell voltage and cell current during the application of external forces. The goal of this project is to assemble, for the first time, an integrated measurement and force application system that will enable the functional role of mechanosensitive channels, transmembrane voltage, and specific membrane currents to be examined in cells having different cytoskeletal architectures. The model system that will be studied is the cardiac myofibroblast, a cell that plays a prominent role in myocardial infarcts and scar formation and is capable of force sensing, force production, and electrophysiological activity. In recent years, micropatterned flexible substrates, such as arrays of elastomeric micrometer-scale posts that deflect under cellular traction forces have emerged as novel systems for measuring cellular contractility with sub-cellular resolution. Further, by embedding magnetic nanoparticles in some of the posts, it is now possible to apply forces to adherent cells while measuring their mechanical responses via the surrounding non-magnetic posts. In this project, magnetic micropost-based force generation and measurement systems will be combined with electrophysiological techniques to enable simultaneous electrical and mechanical stimulation and readout of single cells. This project will be a joint effort between the laboratories of two Investigators with complementary expertise in cardiac electrophysiology, experimental physics, patterned cell growth, magnetism, microfabrication, and cell mechanics. Specific Aim 1 will integrate single cell traction force measurements via the micropost arrays with electrophysiological measurements of transmembrane potential and membrane ionic currents. Micro contact printing will be used to vary the shape of the myofibroblasts to manipulate their internal distribution of actin stress fibers, and to explore the effect of sub-cellular force distributions on transmembrane potential and currents. Specific Aim 2 will integrate magnetic actuation of mechanical forces and strains into the electromechanical readout system developed in Aim 1, and will study the mutual interactions of cellular mechanical and electrophysiological responses to external force and strain. By creating a unified technology for the study of cellular mechanoelectrical function, this project will open new directions for the elucidation of biologically and clinically important systems. ) PUBLIC HEALTH RELEVANCE: This research will combine electrophysiology techniques with recent, advanced developments in magnetic nanotechnology to develop a new platform to study the interplay between mechanical and electrical processes in heart, muscle, and other tissues. A number of diseases have been attributed to abnormal interactions between mechanical and electrical functiontransduction of mechanical cues at the cellular level, including cardiac arrhythmias, polycystic kidney disease, glioma, glaucoma, Duchenne muscular dystrophy and tumorigenesis. This research will enable new insights into cellular mechano-electrical processes at the cellular level, and will have the potential to contribute significantly to the understanding of the progression of these diseases.

描述(申请人提供)：在肌肉、成纤维细胞和骨骼等不同类型的细胞中，细胞可以在响应电生理和机械信号的同时产生收缩或牵引力。虽然这些相互作用的子集已经在机械转导和兴奋-收缩耦合的主题下进行了研究，但要充分理解细胞力学和细胞电生理学之间的相互关系，就需要在外力的作用下同时测量细胞力、细胞电压和细胞电流。该项目的目标是首次组装一个集成的测量和施力系统，使机械敏感通道、跨膜电压和特定的膜电流的功能作用能够在具有不同细胞骨架结构的细胞中得到检测。将研究的模型系统是心肌成纤维细胞，这是一种在心肌梗死和瘢痕形成中发挥重要作用的细胞，能够进行力感知、力产生和电生理活动。近年来，微图案化的柔性基板，如弹性微米级柱子阵列，在细胞牵引力的作用下发生偏转，成为以亚细胞分辨率测量细胞收缩能力的新系统。此外，通过在一些柱子中嵌入磁性纳米颗粒，现在可以向附着的细胞施加力，同时通过周围的非磁性柱子测量它们的机械响应。在这个项目中，基于磁性微柱的力产生和测量系统将与电生理技术相结合，以实现对单个细胞的同时电和机械刺激和读出。这个项目将是两个在心脏电生理学、实验物理、图案化细胞生长、磁性、微制造和细胞力学方面具有互补专业知识的研究人员的实验室共同努力的结果。具体目标1将通过微柱阵列将单电池牵引力测量与跨膜电位和膜离子电流的电生理测量相结合。微接触印迹技术将用于改变肌成纤维细胞的形状，以控制其肌动蛋白应激纤维的内部分布，并探索亚细胞力分布对跨膜电位和电流的影响。特殊目标2将把机械力和应变的磁驱动集成到目标1开发的机电读出系统中，并将研究细胞对外力和应变的机械和电生理反应的相互作用。通过创建一种研究细胞机电功能的统一技术，该项目将为阐明生物和临床上重要的系统开辟新的方向。) 与公共健康相关：这项研究将结合电生理学技术和磁性纳米技术的最新先进发展，开发一个新的平台，研究心脏、肌肉和其他组织中机械和电子过程之间的相互作用。许多疾病被归因于机械和电功能之间的异常相互作用，以及细胞水平的机械信号转导，包括心律失常、多囊肾病、胶质瘤、青光眼、Duchenne肌营养不良和肿瘤发生。这项研究将使人们能够在细胞水平上对细胞的机械-电气过程有新的见解，并将有可能对了解这些疾病的进展做出重大贡献。