Molecular Mechanisms of Myofilament Dysfunction in Heart Failure

心力衰竭肌丝功能障碍的分子机制

基本信息

批准号：
7919147
负责人：
Pieter P. de TOMBE
金额：
$ 38.8万
依托单位：
UNIVERSITY OF ILLINOIS AT CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-06-01 至 2015-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7919147
关键词：
Action Potentials Area Automobile Driving Award Biochemical Calcium Cardiac Cardiac Myocytes Cavia Cell physiology Cells Characteristics Chemicals Collaborations Complement Congestive Heart Failure Contractile Proteins Controlled Study Coupling Data Defect Depressed mood Development Elements Endocardium Epicardium Functional disorder Gene Delivery Generations Goals Harvest Heart Heart Diseases Heart Hypertrophy Heart failure Homeostasis Human Hypertrophy Kinetics Lead Left Link Measures Mechanics Metabolism Microfilaments Modeling Modification Molecular Morphology Muscle Myocardium Myofibrils Myosin Light Chains Paper Pathway interactions Patients Phosphoric Monoester Hydrolases Phosphorylation Phosphotransferases Post-Translational Protein Processing Preparation Production Protein Kinase Proteins Proteomics Recombinant Proteins Regulation Relaxation Research Right ventricular structure Sampling Sarcomeres Secondary to Signal Pathway Site Staging Structure Structure-Activity Relationship Techniques Testing Time Troponin Troponin T Variant Ventricular Dysfunction Work base combat design hemodynamics mortality myosin-binding protein C novel novel therapeutics pressure programs reconstitution research study

项目摘要

Congestive heart failure (CHF) is associated with an abnormality in cardiac cell function. The molecular mechanisms that underlie this depressed function in CHF are unknown. In previous work we have shown that myofilament function is depressed in CHF in terms of depressed maximum force generating capacity, calcium responsiveness, and cross-bridge cycle kinetics. Experimental mechanical/biochemical data suggest that dys-regulated myofilament contractile protein phosphorylation causes myofilament dysfunction in CHF, possibly via altered phosphorylation of myosin light chain (MLC), myosin binding protein C (MyoBPC), and Troponin-l (Tnl). However, the precise structure-function relationship has not been determined. In this proposal for continued support we will employ a well-established model of CHF in the guinea-pig secondary to pressure overload. The guinea-pig model allows study of control, compensatory hypertrophy, and CHF in a model that closely resembles the myofilament and EC-coupling parameters as found in the human. Biochemical proteomics analysis will be used to identify pathways and proteins that are targeted in CHF and the impact of identified post-translational modifications on contractile function will be determined using a variety of biophysical techniques ranging from intact electrically stimulated isolated muscle to single myofibrils (aim 1). Contractile protein post-translational modifications and signal pathways will be manipulated via adenoviral gene delivery, kinase/phosphatase treatment and recombinant protein contractile protein exchange in permeabilized isolated myocardium (aim 1). As we recently demonstrated, regional myofilament function is not uniform in the heart and this distribution is significantly altered in heart failure. Experiments proposed in specific aim 2 will determine the signal pathways and contractile protein posttranslational modifications that underlie these phenomena. Finally, experiments proposed in aim3 will determine the dynamic and temporal coupling between the driving Ca2+ transient and the mechanical dynamic contractile protein force production; these experiments will be performed in single cardiac myofibrils. Overall, our aim is to determine the mechanisms that underlie contractile protein dysfunction in CHF. Our research will aid in the development of new therapeutic strargies to combat OHF in patients.

充血性心力衰竭（CHF）与心脏细胞功能异常有关。 CHF中这种抑郁症功能的基础的分子机制尚不清楚。在先前的工作中，我们已经表明，肌丝功能在CHF的最大产生能力，钙反应能力和跨桥循环动力学方面处于降低。实验机械/生化数据表明，Dys调节的肌丝收缩蛋白磷酸化会导致CHF中的肌膜功能障碍，这可能是通过肌球蛋白光链（MLC），肌球蛋白结合蛋白C（MyOBPC）和MyOBPC的磷酸化改变而引起的。 Troponin-L（TNL）。但是，尚未确定确切的结构功能关系。在这项持续支持的建议中，我们将采用继发压力超负荷的几内亚猪中的CHF模型。豚鼠模型允许在与人类中发现的相似类似于肌丝和EC偶联参数的模型中研究对照，补偿性肥大和CHF。生化蛋白质组学分析将用于识别针对CHF的途径和蛋白质，并且将使用鉴定的翻译后修饰对收缩功能的影响将使用从完整的电刺激的孤立肌肉到单个肌原纤维的多种生物物理技术（AIM 1）。收缩蛋白的翻译后修饰和信号途径将通过腺病毒基因递送，激酶/磷酸酶处理以及重组蛋白收缩蛋白在透化的分离心肌中的交换来操纵（AIM 1）。正如我们最近所证明的那样，区域肌丝功能在心脏中并不统一，并且这种分布在心力衰竭中发生了明显改变。特定目标2中提出的实验将确定基于这些现象的基础的信号途径和收缩蛋白的翻译后修饰。最后，在AIM3中提出的实验将确定驱动Ca2+瞬态与机械动态收缩蛋白力产生之间的动态和时间耦合。这些实验将在单个心脏肌纤维中进行。总体而言，我们的目的是确定CHF中收缩蛋白功能障碍的机制。我们的研究将有助于开发新的治疗性跨度，以对抗患者的OHF。