Project 1:Diabetes, RAGE/DIAPH1 and Myocardial Infarction

项目1：糖尿病、RAGE/DIAPH1与心肌梗塞

• 批准号: 10642708
• 负责人: Ravichandran Ramasamy
• 金额: $ 56.49万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10642708
• 关键词: Address; Attenuated; Binding; Bioinformatics; Bone Marrow; Calcium; Cardiac; Cardiac Myocytes; Cardiovascular Diseases; Cell Communication; Cell Death; Cell Death Signaling Process; Cell Separation; Cells; Collaborations; Cytoplasmic Tail; Data; Diabetes Mellitus; Endoplasmic Reticulum; Endothelial Cells; Energy Metabolism; Fluorescence-Activated Cell Sorting; Foundations; Genetic Transcription; Glucose; Goals; Guanosine Triphosphate Phosphohydrolases; Heart; Hyperglycemia; Infarction; Inflammation; Injury; Ischemia; Knockout Mice; Ligands; LoxP-flanked allele; Macrophage; Magnetic Resonance Spectroscopy; Mass Spectrum Analysis; Measurement; Mediating; Metabolic; Metabolic dysfunction; Mitochondria; Molecular; Monitor; Morbidity - disease rate; Mus; Myocardial Infarction; Myocardial Ischemia; Myocardium; Oxidative Stress; Patients; Perfusion; Play; Process; Proteomics; Publishing; RAGE gene; Recovery; Recovery of Function; Regional Perfusion; Regulation; Reperfusion Injury; Reperfusion Therapy; Role; Sarcoplasmic Reticulum; Signal Transduction; Stress; Techniques; Testing; Therapeutic; Therapeutic Intervention; Tissues; Transplantation; Wild Type Mouse; Work; antagonist; cell motility; diabetic; heart cell; improved; in vivo; in vivo Model; ischemic injury; limb ischemia; monocyte; mortality; mouse model; mutant; myocardial injury; novel; preservation; programs; receptor for advanced glycation endproducts; recruit; repaired; rho GTP-Binding Proteins; small molecule; transcriptomics

Project Summary: Project 1 Cardiovascular disease (CVD), that include increased sensitivity of diabetic (DM) myocardium to ischemic injury, represents the major cause of morbidity and mortality in patients with diabetes. We have uncovered key roles for the receptor for advanced glycation end products (RAGE -gene symbol Ager) in DM and myocardial ischemia/reperfusion (I/R), as global deletion of Ager attenuated myocardial injury, reduced oxidative stress, increased functional recovery and preservation of ATP compared to wild-type (WT) littermates. Mechanisms by which Ager deletion confers metabolic and functional protection in DM and non-DM (NDM) I/R hearts will be the focus of this project. Our program discovered that the RAGE cytoplasmic domain interacts with diaphanous-1 (DIAPH1), an effector of RhoGTPases, is essential for RAGE ligand-mediated cellular migration and activation of cdc42/rac-1. Our recent studies demonstrated that DIAPH1 is expressed in cardiomyocytes (CMs) and that I/R increases expression of Diaph1. Key preliminary data reveal reduced infarct size and improved functional recovery after I/R in (a) WT mice transplanted with bone marrow derived cells from Ager null mice,(b) mice with CM specific deletion of Ager/Diaph1, and (c) WT mice hearts perfused with conditioned media from Ager null or Diaph1 null macrophages (MΦs). Novel findings in CMs and MΦs reveal that DIAPH1 interacts with mitochondrial GTPase mitofusin2 (MFN2) and augments MFN2's tethering of sarcoplasmic reticulum (SR) to mitochondria (mito) and consequently mito calcium regulation. Importantly, our data shows that high glucose, ligands of RAGE, and RAGE-DIAPH1 interaction further augments DIAPH1-MFN2 driven mito-SR tethering. Taken together, these data led us to hypothesize that RAGE/DIAPH1 mediates DIAPH1-MFN2 driven Mito- SR interactions, altered calcium regulation, cell death signaling and metabolic dysfunction in I/R hearts by cell intrinsic mechanisms in MΦs, and via MΦ-CM cross-talk. We will probe comprehensive mechanisms in cardiac stresses evoked by I/R using murine models, both in the absence and presence of DM. We will employ novel Ager and Diaph1 floxed mice, small molecule antagonists of RAGE-DIAPH1 interaction, state-of-the-art molecular techniques, proteomics, and magnetic resonance spectroscopy to uncover mechanisms of I/R injury in DM hearts.Proposed studies in this project will identify novel mechanism MΦ specific mechanism, as well as MΦ-CM cross talk mechanisms by which RAGE-DIAPH1 modulates I/R injury in hearts, particularly in DM hearts. Identification of these mechanisms, along with testing of novel small molecules that block RAGE/DIAPH1 interaction, will pave the way for therapeutic interventions to protect DM hearts from I/R injury. Project 1 will work closely with Projects 2 and 3 and the two Cores to achieve these goals.

项目概要：项目1 心血管疾病（CVD），包括糖尿病（DM）心肌对缺血性损伤的敏感性增加， 是糖尿病患者发病和死亡的主要原因。我们发现了一些关键角色 对于DM和心肌梗死患者晚期糖基化终末产物受体（β-基因符号Ager）， 缺血/再灌注（I/R），因为Ager的整体缺失减轻了心肌损伤，降低了氧化应激， 与野生型（WT）同窝仔相比，ATP的功能恢复和保存增加。机制 其中Ager缺失在DM和非DM（NDM）I/R心脏中赋予代谢和功能保护， 成为这个项目的焦点。我们的程序发现，胞质结构域与 diaphanous-1（DIAPH 1）是RhoGTPases的效应子，在RhoGTPases配体介导的细胞迁移中起重要作用 和CDC 42/RAC-1的活化。我们最近的研究表明DIAPH 1在心肌细胞中表达， (CMs)I/R增加了Diaph 1的表达。关键的初步数据显示， （a）移植有来自Ager缺失的骨髓衍生细胞的WT小鼠中I/R后改善的功能恢复 小鼠，（B）具有Ager/Diaph 1的CM特异性缺失的小鼠，和（c）用条件培养基灌注的WT小鼠心脏 来自Ager null或Diaph 1 null巨噬细胞（MΦs）。CM和MΦ中的新发现揭示DIAPH 1相互作用 与线粒体GTP酶mitofusin 2（MFN 2）结合，并增强MFN 2对肌浆网（SR）的束缚 线粒体（mito），因此mito钙调节。重要的是，我们的数据显示高血糖， RAGE-DIAPH 1相互作用进一步增强DIAPH 1-MFN 2驱动的线粒体-SR束缚。 综上所述，这些数据使我们假设，MIPH 1/DIAPH 1介导DIAPH 1-MFN 2驱动的Mito-2。 I/R心脏中SR相互作用、钙调节改变、细胞死亡信号和代谢功能障碍 通过MΦ中的细胞内在机制，以及通过MΦ-CM串扰。我们将探索全面的机制， 使用小鼠模型，在不存在和存在DM的情况下，I/R诱发的心脏应激。我们会委聘 新型Ager和Diaph 1 floxed小鼠，RAGE-DIAPH 1相互作用的小分子拮抗剂，最新技术水平 分子技术、蛋白质组学和磁共振波谱学来揭示I/R损伤的机制 在DM心脏中。该项目中提出的研究将确定新的机制MΦ特异性机制，以及 RAGE-DIAPH 1调节心脏（特别是DM心脏）I/R损伤的MΦ-CM串扰机制。 这些机制的鉴定，沿着对阻断CD 4/DIAPH 1的新型小分子的测试 这种相互作用将为保护DM心脏免受I/R损伤的治疗干预铺平道路。项目1将 与项目2和3以及两个核心密切合作，以实现这些目标。