Elucidating the role of cardiac myofibroblasts on matrix and vasculature remodeling

阐明心肌成纤维细胞对基质和脉管系统重塑的作用

基本信息

批准号：
9909793
负责人：
EMILY OLSZEWSKI
金额：
$ 4.07万
依托单位：
UNIVERSITY OF WASHINGTON
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-05-16 至 2023-05-15
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9909793
关键词：
3-Dimensional Affect Aging Aortic Valve Stenosis Apoptosis Area Arteries Artificial Heart Atomic Force Microscopy Automobile Driving Biochemical Biometry Blood Vessels Cardiac Cardiac Myocytes Cardiovascular Physiology Cause of Death Cells Characteristics Chemical Structure Chemicals Chemistry Collagen Collagen Fiber Confocal Microscopy Contracts Coronary Cues Data Deposition Disease Endothelial Cells Endothelium Engineering Environment Extracellular Matrix Extracellular Space Fibroblasts Fibrosis Freeze Drying Gel Gene Activation Generations Genetic Models Goals Heart Heart Diseases Heart failure Hypertension Hypertrophy Image In Vitro Injury Lectin Left Length Liquid Chromatography Longitudinal Studies MAP2K6 gene Maps Measurement Measures Mechanics Mediating Methods Modeling Molecular Mus Myocardial Infarction Myofibroblast Nature Operative Surgical Procedures Organ Pathway interactions Perfusion Perivascular Fibrosis Phenotype Phosphotransferases Physiological Physiology Preparation Process Property Protein Kinase Proteomics Pump Regulation Role Signal Transduction Stimulus Stress Stretching Structure System Therapeutic Three-Dimensional Image Time Tissues Traction Transgenes Transgenic Mice Vascular remodeling Ventricular Work blebbistatin cell growth cell motility cell type combinatorial coronary fibrosis density experimental study extracellular heart function image reconstruction in vitro Model in vivo in vivo Model interstitial knock-down mathematical model mechanical properties microscopic imaging migration overexpression preservation pressure response scaffold second harmonic tandem mass spectrometry two-photon

项目摘要

In every form of heart disease, the secretion of extracellular matrix (ECM) by activated fibroblasts, or myofibroblasts, results in cardiac fibrosis. Fibrosis impedes compliance and pumping function, ultimately leading to heart failure due to left ventricular dilation and loss of mechanical function. Little is known about endothelial cell and vessel adaptations to the environment or how local mechanics and chemistry impact vessel structure and flow in vivo. Combinatorial fibroblast and ECM mechanical and chemical crosstalk with endothelial cells are unknown. Moreover, in vitro models aiming to assess vascular adaptations to an extracellular environment lack physiologically relevant ECMs and instead provide exogenous ECM components to optimize control of variables. A system for in vivo, cell-specific phenotypic manipulation will allow for controlled perturbations at an organ level while maintaining relevant, native ECM remodeling over time. Thus, I propose to examine transgenic mice with cardiac fibroblast-specific overexpression of a constitutively active mitogen-activated protein kinase kinase 6 (MKK6) to study vascular remodeling with respect to the fibroblasts and the ECM they secrete. These mice were previously shown to develop interstitial and perivascular fibrosis after 16-20 weeks of the MKK6 gene activation without an injury stimulus, serving as an effective model of the interstitial fibrosis preserved across the results of aging, hypertension, aortic stenosis, and other diseases of the heart. Importantly, the remodeling seen in these diseases does not involve a massive loss of cardiomyocytes, as in a myocardial infarction, but rather a conserved fibroblast phenotypic change, an altered extracellular space, and/or restricted vascular flow over time. Similarly, manipulation of the MKK6 pathway allows for overexpression or knockdown of cardiac fibroblast activation, corresponding to increased ECM or the inability to secrete ECM as a response to a stimulus, respectively. First, I propose to study the biochemical, structural, and mechanical properties of the ECM as well as the macro- and microvascular responses to activated, quiescent, and control cardiac fibroblast phenotypes in vivo. Second, three-dimensional vessel-like structures with controlled fibroblasts and ECMs will be engineered as in vitro platforms to define the molecular regulators of vascular remodeling induced by microenvironmental cues. The effects of combined signaling will be resolved by global characterization along with a reductionist method. The goal of this work is to inform heart therapies by providing targets for steering cardiac vascular remodeling.

在各种形式的心脏病中，细胞外基质 (ECM) 的分泌成纤维细胞或肌成纤维细胞导致心脏纤维化。纤维化妨碍依从性和泵血功能，最终因左心室扩张和丧失而导致心力衰竭机械功能。关于内皮细胞和血管对环境的适应知之甚少。环境或局部力学和化学如何影响体内血管结构和流动。成纤维细胞和 ECM 与内皮细胞的机械和化学串扰的组合未知。此外，体外模型旨在评估血管对细胞外的适应环境缺乏生理相关的 ECM，而是提供外源 ECM 组件来优化变量的控制。体内细胞特异性表型系统操纵将允许在器官水平上进行受控扰动，同时保持相关性，随着时间的推移，原生 ECM 重塑。因此，我建议检查具有心脏功能的转基因小鼠组成型活性丝裂原激活蛋白激酶的成纤维细胞特异性过表达激酶 6 (MKK6) 用于研究成纤维细胞及其 ECM 的血管重塑分泌。先前显示这些小鼠在接受治疗后会出现间质和血管周围纤维化。在没有损伤刺激的情况下，MKK6 基因激活 16-20 周，作为有效的间质纤维化模型保留了衰老、高血压、主动脉疾病的结果狭窄和其他心脏疾病。重要的是，这些疾病中出现的重塑并不像心肌梗死那样涉及心肌细胞的大量损失，而是保守的成纤维细胞表型变化、细胞外空间改变和/或受限血管流量随时间的变化。类似地，操纵 MKK6 通路可实现过度表达或心脏成纤维细胞活化的敲低，对应于 ECM 增加或无法分别分泌 ECM 作为对刺激的反应。首先，我建议研究 ECM 的生化、结构和机械特性以及宏观和微血管对激活、静止和控制心脏成纤维细胞表型的反应体内。其次，具有受控成纤维细胞和 ECM 的三维血管样结构将被设计为体外平台来定义血管重塑的分子调节剂由微环境因素诱发。组合信号的影响将通过以下方式解决全局表征以及还原论方法。这项工作的目标是让心脏了解通过提供指导心脏血管重塑的目标来进行治疗。