Novel Cell-in-Gel System for Mechanotransduction Study at the Single Cell Level

用于单细胞水平机械转导研究的新型凝胶细胞系统

基本信息

批准号：
9321940
负责人：
Ye Chen-Izu
金额：
$ 39.16万
依托单位：
UNIVERSITY OF CALIFORNIA AT DAVIS
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-08-01 至 2019-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9321940
关键词：
3-Dimensional Arrhythmia Avidin Biochemical Reaction Biological Biology Biomedical Engineering Blood Circulation Cardiac Myocytes Cardiomyopathies Cell surface Cells Chemistry Complex Computer software Contracts Data Defect Devices Diastole Dilated Cardiomyopathy Dystroglycan Dystrophin Engineering Environment Focal Adhesions Functional disorder Gel Glass Glycoproteins Goals Heart Heart Diseases Heart failure Hydrogels Hypertension Image Integrins Lead Masks Measures Mechanical Stress Mechanics Molecular Molecular Target Molecular and Cellular Biology Muscle Muscle Cells Muscular Dystrophies Mutation Myocardial dysfunction Myocardium Pathway interactions Pharmaceutical Preparations Pharmacotherapy Polymers Proteins Role Scientist Signal Pathway Signal Transduction Stress Stretching Structural Protein Synthesis Chemistry System Systole Talin Techniques Technology Testing Time Vinculin base blood pump carbon fiber cell type crosslink effective therapy experience experimental study hemodynamics in vivo innovation mathematical model mechanical force mechanical load mechanotransduction mouse model new technology novel pressure protein complex public health relevance response retinal rods shear stress tool

项目摘要

DESCRIPTION (provided by applicant): The heart senses the changing mechanical load and adjusts the contractile strength, on a beat-to-beat basis, to match the load in order to effectivel pump blood into circulation. High blood pressure often leads to arrhythmias and heart diseases. Defects in structural proteins, such as in muscular dystrophy, can also lead to cardiomyopathy. How do the cardiomyocytes sense and respond to mechanical forces? What molecules serve as mechanosensors? What are the signaling pathways that transduce mechanical stress to biochemical reactions in the cell? All these important questions need to be answered by investigating the mechano-chemo- transduction (MCT) mechanisms at cellular and molecular levels. A major hindrance to studying MCT mechanisms is a lack of technology to achieve two important capabilities: one is to control mechanical stress at the single cell level in 3-D environment mimicking the myocardium; the other is to tug on specific cell-surface mechanosensors during myocyte contraction in order to interrogate their role in MCT. However, all currently available techniques come short of having both capabilities. In this project, the PI and her interdisciplinary team will combine synthetic chemistry, muscle mechanics, and cellular and molecular biology to achieve two major goals: one is the bioengineering goal to develop an innovative `Cell-in-Gel' system that have the above two capabilities; the other is the scientific goal of using the new tools to investigate the MCT mechanisms during cardiomyocyte contraction under mechanical load. The Cell-in-Gel system has two major advantages over existing techniques (stretching cells using carbon fibers or glass rods). (1) Live cardiomyocytes are embedded in a 3-D hydrogel (elastic matrix composed of crosslinking polymers) so they experience 3-D mechanical stresses (longitudinal tension, transverse compression, shear stress) during contraction, mimicking the in vivo environment. (2) The gel chemistry allows tethering specific cell-surface mechanosensors (e.g. dystroglycans, integrins) to the gel matrix to impose mechanical stress on them during cell contraction. The Cell-in-Gel system will enable scientists to study MCT complexes, their downstream signaling, and functional consequences in live cardiomyocytes and other cell types. We will test the central hypothesis that two major MCT complexes in cardiomyocytes-the dystrophin-glycoprotein complex (DGC) and the vinculin-talin-integrin complex (VTI)- transduce mechanical stress to modulate the Ca2+ signaling system on a beat-to-beat basis, which enhances Ca2+ transient and contractility in response to mechanical load, but this same mechanism can also cause Ca2+ dysregulation under excessive load. Resolving this MCT mechanism is fundamental to understanding how the heart responds to mechanical load to autoregulate contractility, how excessive loads cause heart diseases, and how DGC mutations in muscular dystrophy lead to Ca2+ dysregulation and cardiac dysfunction.

描述（由适用提供）：心脏会感觉到机械负载的变化，并以节拍对基础调整收缩力，以匹配负载，以便有效地将血液泵入循环。高血压通常会导致心律不齐和心脏病。结构蛋白的缺陷，例如肌营养不良症，也会导致心肌病。心肌细胞如何感知并对机械力反应？哪些分子用作机制？将机械应力转化为细胞中的生化反应的信号通路是什么？所有这些重要问题需要通过研究细胞和分子水平的机理 - 化学转移（MCT）机制来回答。研究MCT机制的一个主要障碍是缺乏实现两个重要功能的技术：一种是在模仿心肌的3-D环境中控制单细胞水平的机械应力；另一个是在肌细胞收缩期间拖延特定的细胞表面机制，以询问其在MCT中的作用。但是，当前所有可用的技术都没有两个功能。在这个项目中，PI和她的跨学科团队将结合合成化学，肌肉机制以及细胞和分子生物学，以实现两个主要目标：一个是开发具有以上两个功能的创新的“细胞内凝胶”系统的生物工程目标；另一个是科学目标是使用新工具在机械负载下调查心肌细胞收缩期间的MCT机制。与现有技术（使用碳纤维或玻璃棒拉伸细胞）相比，细胞内凝胶系统具有两个主要优势。（1）活心肌细胞嵌入到3-D水凝胶（由交联聚合物组成的弹性基质）中，因此它们在收缩过程中经历3-D机械应力（纵向张力，横向压缩，剪切应力），模仿体内环境。（2）凝胶化学允许将特定的细胞表面机理（例如，多糖蛋白，整联蛋白）绑定到凝胶基质中，以在细胞收缩期间对它们施加机械应力。细胞内凝胶系统将使科学家能够研究MCT复合物，其下游信号传导以及实时心肌细胞和其他细胞类型的功能后果。我们将测试中心假设，即心肌细胞中的两个主要MCT复合物 - 肌营养不良蛋白 - 糖蛋白复合蛋白复合物（DGC）和Vinculin-talin-----------------触发系统的机械压力（VTI） - 跨性压力，以使CA2+信号系统在Beat-Beat基础上调节CA2+临时响应，从而使CA2+信号系统调节，从而增强了响应的响应，但可以调节响应的机制，但可以调节CA2+信号系统，但可以调节CA2+信号系统。在超额负载下失调。解决这种MCT机制对于了解心脏如何应对机械负荷以自动调节收缩性，过度负荷导致心脏病以及肌肉营养不良中的DGC突变导致CA2+功能障碍和心脏功能障碍的方式至关重要。