Investigation of therapeutic potential of exogenous ubiquitin following myocardial ischemia/reperfusion injury

外源性泛素治疗心肌缺血/再灌注损伤潜力的研究

基本信息

批准号：
10619513
负责人：
KRISHNA SINGH
金额：
--
依托单位：
JAMES H QUILLEN VA MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-04-01 至 2024-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10619513
关键词：
AMD3100 Actins Address Adult Affect Apoptosis Area Biochemical Biology CXCR4 gene Cardiac Cause of Death Cicatrix Co-Immunoprecipitations Collagen Data Deposition Development Eukaryotic Cell Event Extracellular Matrix Fibroblasts Fibrosis Gel Heart Human In Vitro Infarction Inflammatory Response Investigation Ischemia Knockout Mice Left Ventricular Function Leukemic Cell MAPK3 gene Macrophage Measures Modeling Molecular Molecular Weight Mus Myocardial Infarction Myocardial Ischemia Myocardial Reperfusion Injury Myocarditis Myocardium Myofibroblast Outcome Patient-Focused Outcomes Patients Peptides Phagocytes Phenotype Play Proteins Regulation Reperfusion Injury Reperfusion Therapy Role Signal Transduction Smooth Muscle Specificity Stimulation of Cell Proliferation Testing Therapeutic Toxic effect Ubiquitin VEGFA gene Ventricular Remodeling Veterans antagonist beta-adrenergic receptor cardioprotection cell type clinically relevant cost effective extracellular healing heart function heart preservation improved improved outcome in vivo innovation migration mouse model mutant neutrophil novel novel strategies novel therapeutic intervention receptor regeneration potential response treatment strategy wound

项目摘要

Ischemic heart disease (IHD) is a leading cause of death among veterans. Myocardial infarction (MI) is a serious outcome of IHD, and is generally attributable to the detrimental effects of myocardial ischemia/reperfusion (I/R) injury. Cardiac inflammation and extracellular matrix deposition (scar formation) are essential events in the cardiac remodeling post-MI. Therapeutic approaches targeting these events may hold promise for patients with MI. This proposal investigates the therapeutic potential of ubiquitin (UB; a small molecular weight protein typically associated with tagging proteins for proteasomal degradation) in myocardial remodeling following myocardial ischemia and I/R injury. The proposal is based on our novel observations that exogenous UB plays a protective role in β- adrenergic receptor-stimulated myocardial remodeling. In human THP1 leukemia cells, CXCR4 is identified as a receptor for extracellular UB. Our preliminary data using - i) isolated heart model of global ischemia/reperfusion (I/R; Langendorff model); and ii) in vivo myocardial I/R injury in mice now suggest a protective role of exogenous UB in myocardial remodeling following I/R injury. UB treatment decreased infarct size, reduced cardiac inflammatory response and improved heart function 3 days post-I/R. In vitro, UB treatment inhibited migration of neutrophils, and enhanced phagocytic activity of macrophages. In adult cardiac fibroblasts, UB treatment activated ERK1/2, and increased expression of vascular endothelial growth factor-A (VEGF-A). UB co-immunoprecipitated with CXCR4, and CXCR4 antagonism negated the effects of extracellular UB on ERK1/2 activation and VEGF-A expression. UB treatment augmented α-smooth muscle actin (a marker for myofibroblast differentiation) expression and collagen gel contractile activity of fibroblasts, while decreasing migration of fibroblasts into the wound area and inhibiting FBS-stimulated cell proliferation. These observations led us to hypothesize that exogenous UB, most likely acting via CXCR4, modulates cardiac inflammatory response and extracellular matrix biology by affecting phenotype and/or function of neutrophils, macrophages and fibroblasts, thereby playing a cardioprotective role in myocardial remodeling following ischemia and I/R injury. Aim 1 will investigate, in vivo, the therapeutic potential of exogenous UB in myocardial remodeling following myocardial ischemia and I/R injury. Aim 2 will examine, in vivo, the role of CXCR4 in modulation of cardioprotective effects of exogenous UB using CXCR4 antagonist, UB mutants and cell type-specific CXCR4 knockout mice. Aim 3 will investigate the cellular and molecular mechanisms by which exogenous UB affects cardiac inflammatory response and extracellular matrix biology to coordinate post-I/R cardioprotective response. The Innovation of this project lies in the investigation of therapeutic potential of exogenous UB in myocardial remodeling following myocardial ischemia and I/R injury (clinically relevant model). The proposed studies investigating the role of exogenous UB in cardiac inflammation and extracellular matrix biology may uncover novel strategies for the treatment of IHD.

缺血性心脏病（IHD）是退伍军人死亡的主要原因。心肌梗塞（MI）是 IHD的严重结果，通常归因于心肌的有害影响缺血/再灌注（I/R）损伤。心脏感染和细胞外基质沉积（疤痕形成）是MI后心脏重塑的重要事件。靶向治疗方法这些事件可能对MI患者有希望。该建议调查了治疗潜力泛素（UB；一种小分子量蛋白，通常与标记蛋白有关心肌缺血和I/R损伤后心肌重塑的蛋白酶体降解）。这提案是基于我们新颖的观察结果，即外源UB在β-中起受保护的作用肾上腺素受体刺激的心肌重塑。在人类THP1白血病细胞中，CXCR4为被识别为细胞外UB的接收器。我们使用 - i）全局的孤立心脏模型的初步数据缺血/再灌注（I/R; Langendorff模型）; ii）现在的小鼠体内心肌I/R损伤建议 I/R损伤后，外源UB在心肌重塑中的受保护作用。 UB治疗梗塞大小降低，心脏炎症反应降低和心脏功能改善3天 i/r。在体外，UB治疗抑制了中性粒细胞的迁移，并增强了巨噬细胞。在成人心脏成纤维细胞中，UB治疗激活ERK1/2，表达增加血管内皮生长因子-A（VEGF-A）的。 UB与CXCR4和CXCR4共免疫沉淀拮抗作用否定了细胞外UB对ERK1/2激活和VEGF-A表达的影响。 UB 治疗增强α-平滑肌肌动蛋白（肌纤维细胞分化的标记）表达成纤维细胞的胶原蛋白凝胶收缩活性，同时减少成纤维细胞迁移到伤口区域并抑制FBS刺激的细胞增殖。这些观察结果使我们假设这种外源UB，最有可能通过CXCR4作用，调节心脏炎症反应和细胞外基质生物学通过影响中性粒细胞，巨噬细胞和/或功能的表型和/或功能成纤维细胞，从而在心肌重塑后扮演心脏保护作用受伤。 AIM 1将在体内调查心肌中外源UB的治疗潜力心肌缺血和I/R损伤后进行重塑。 AIM 2将在体内检查CXCR4的作用使用CXCR4拮抗剂，UB突变体和细胞类型特异性CXCR4基因敲除小鼠。 AIM 3将研究细胞和分子机制外源UB会影响心脏炎症反应和细胞外基质生物学对协调i/r心脏保护响应。该项目的创新在于调查心肌缺血后心肌重塑中外源UB的治疗潜力 I/R伤害（临床相关模型）。提出的研究研究了外源UB的作用在心脏感染和细胞外基质生物学中可能会发现治疗的新策略 IHD。