Interaction of Cardiotonic Drugs with Cardiac Troponin

强心药与心肌肌钙蛋白的相互作用

基本信息

批准号：
7269825
负责人：
Brian Douglas Sykes
金额：
$ 13.11万
依托单位：
UNIVERSITY OF ALBERTA
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-08-04 至 2010-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7269825
关键词：
Address Affinity Amides Amino Acids Amplifiers Area Attenuated Bepridil Binding Binding Proteins Binding Sites Biological Cardiac Cardiac Muscle Contraction Cardiac Myocytes Cardiotonic Agents Cell Nucleus Chemicals Complex Computational Technique Contracts Data Development Diagnostic Disease Drug Binding Site Drug Compounding Drug Design Drug Interactions Drug effect disorder Electronics Environment Equilibrium Fiber Generations Goals Heart Heart Diseases Heart failure In Situ In Vitro Investigation Kinetics Knowledge Label Lead Levosimendan Ligands Liquid substance Location Mathematics Medical Methodology Methods Microfilaments Modeling Modification Molecular Molecular Biology Molecular Conformation Molecular Structure Molecular Weight Monitor Morbidity - disease rate Movement Muscle Contraction Muscle Fibers Mutation Myocardium N Domain NMR Spectroscopy NOESY Nature Noise Nuclear Nuclear Magnetic Resonance Numbers Object Attachment Pathology Personal Satisfaction Pharmaceutical Preparations Phosphorylation Physiologic pulse Physiology Plastics Process Protein Binding Protein Subunits Proteins Pulse taking Pump Range Rationalization Recombinant Proteins Regulation Relaxation Research Research Personnel Residual state Resolution Rest Role Sampling Sarcomeres Shapes Signal Pathway Signal Transduction Site Societies Solutions Specificity Speed Standards of Weights and Measures Structure Structure-Activity Relationship TOCSY Techniques Testing Therapeutic Therapeutic Intervention Thick Thin Filament Time Titrations Troponin Troponin C Troponin I Troponin T Width Work base caN protocol computer program design heart function improved insight interest molecular dynamics mortality pharmacophore protein structure reconstitution research study size solid state stoichiometry three dimensional structure tool

项目摘要

DESCRIPTION (provided by applicant): The overall goal of the proposed research is to elucidate the molecular mechanisms involved in the regulation of cardiac muscle contraction by troponin and to determine its role as a target for the development of therapeutic protocols that can be used to attenuate heart disease, the leading cause of morbidity and mortality in the Western society. The hypothesis behind the proposed research is that troponin is a molecular switch, directly regulating the Ca2+-dependent activation of myofilament in cardiac muscle contraction and therefore serves as an attractive and logical target for the design of cardiotonic drugs. These drugs are clinically useful because they can be used to modulate the Ca2+-sensitivity of troponin. This approach is therapeutically desirable because intracellular [Ca2+] is not perturbed, preserving the regulation of other Ca2+-based signaling pathways. Towards defining cardiotonic structure-activity relationships, we have shown that several cardiotonic agents specifically bind troponin C (cTnC) and determined high resolution structures of two cTnC-drug complexes, the C-domain of cTnC in complex with EMD 57033, cCTnC.2Ca2+.EMD57033, and the N-domain of cTnC in complex with bepridil and the switch region of cardiac troponin I (cTnI), cNTnC.Ca2+.cTnl147-163.bepridil. These structures have provided a basis for our ongoing effort in addressing the key issues such as: 1) what is the mechanism underlining the mode of action of cardiotonic drugs on cTnC; 2) what is the common pharmacophore responsible for the action of these drugs; 3) what are the effects of these drugs on the structure of troponin in vitro and in situ. Our major tool is nuclear magnetic resonance (NMR) spectroscopy, especially the use of multi-nuclear and multi- dimensional NMR techniques combined with the computational techniques of energy minimization and molecular dynamics to determine the structure of proteins in solution. We will also develop wide line 19F NMR methodologies that can be utilized to study proteins and drugs embedded in muscle fibers. Our specific aims are to 1) elucidate the nature and significance of the effective binding sites of drugs on cTnC and determine the three dimensional solution structures of cTnC-drug complexes, 2) evaluate the relevance of these structures in the whole troponin complex, 3) test the relevance of these structures in muscle fibers. Knowledge gained from this research will help to understand the molecular mechanism underlining the pharmacological effects of the drugs under investigation and will provide insights into the features that are important for the design of cardiotonic drugs in general.

描述（申请人提供）：拟议研究的总体目标是阐明肌钙蛋白调节心脏肌肉收缩的分子机制，并确定其作为开发治疗方案的目标的作用，可用于减弱治疗方案心脏病，是西方社会发病和死亡率的主要原因。拟议的研究背后的假设是，肌钙蛋白是一种分子开关，直接调节心脏肌肉收缩中肌丝的Ca2+依赖性激活，因此是心脏化药物设计的有吸引力和逻辑的目标。这些药物在临床上很有用，因为它们可用于调节肌钙蛋白的Ca2+敏感性。这种方法在治疗上是可取的，因为细胞内[Ca2+]不受干扰，从而保留了其他基于CA2+的信号通路的调节。为了定义心脏的结构 - 活性关系，我们表明几种心源剂特异性结合了肌钙蛋白C（CTNC），并确定了两个CTNC-drug复合物的高分辨率结构，即与EMD 57033，CCTNC.2CA2+CTNC中CTNC的C TNC CTNC的C-domain。 EMD57033，与Bepridil的CTNC的N域和心脏肌钙蛋白I（CTNI）的开关区域，CNTNC.CA2+.CTNL147-163.BEPRIDIL。这些结构为我们持续解决关键问题的努力提供了基础，例如：1）强调心脏药物在CTNC上的作用方式的机制是什么？ 2）什么是负责这些药物作用的常见药效团； 3）这些药物对肌钙蛋白在体外和原位的结构有什么影响。我们的主要工具是核磁共振（NMR）光谱，尤其是使用多核和多维NMR技术，结合了能量最小化和分子动力学的计算技术来确定溶液中蛋白质的结构。我们还将开发宽线19F NMR方法，可用于研究嵌入肌肉纤维中的蛋白质和药物。我们的具体目的是1）阐明药物在CTNC上有效结合位点的性质和意义，并确定CTNC-Prug配合物的三维溶液结构，2）评估这些结构在整个肌钙蛋白复合物中的相关性，3）测试这些结构在肌肉纤维中的相关性。从这项研究中获得的知识将有助于理解强调正在研究的药物的药理作用的分子机制，并将提供有关对心脏药物设计至关重要的特征的见解。