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

• 批准号: 10371145
• 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
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10371145
• 关键词: AMD3100; Address; Adult; Affect; Apoptosis; Area; Biochemical; Biology; CXCR4 gene; Cardiac; Cause of Death; Cell Proliferation; Cicatrix; Collagen; Data; Deposition; Development; Eukaryotic Cell; Event; Extracellular Matrix; Fibroblasts; Fibrosis; Gel; Heart; Human; In Vitro; Infarction; Inflammatory Response; Investigation; Ischemia; Knockout Mice; Lead; Left Ventricular Function; Leukemic Cell; MAPK3 gene; Measures; Modeling; Molecular; Molecular Weight; Mus; Myocardial Infarction; Myocardial Ischemia; Myocarditis; Myocardium; Myofibroblast; Outcome; Patient-Focused Outcomes; Patients; Peptides; Phagocytes; Phenotype; Play; Proteins; Regulation; Reperfusion Injury; Reperfusion Therapy; Role; Signal Transduction; Smooth Muscle Actin Staining Method; Specificity; Testing; Therapeutic; Toxic effect; Ubiquitin; VEGFA gene; Ventricular Remodeling; Veterans; antagonist; base; beta-adrenergic receptor; cardioprotection; cell type; clinically relevant; cost effective; extracellular; healing; heart function; heart preservation; improved; improved outcome; in vivo; innovation; macrophage; migration; mouse model; mutant; neutrophil; novel; novel strategies; novel therapeutic intervention; receptor; regeneration potential; response; treatment strategy; wound

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。心肌梗死（MI） 这是IHD的严重后果，通常可归因于心肌梗死的有害影响。 缺血/再灌注（I/R）损伤。心脏炎症和细胞外基质沉积（瘢痕 形成）是MI后心脏重塑中的重要事件。靶向治疗方法 这些事件可能为MI患者带来希望。该提案研究了治疗潜力 泛素（UB;一种小分子量蛋白，通常与标记蛋白相关， 蛋白酶体降解）在心肌缺血和I/R损伤后心肌重构中的作用。的 该提议是基于我们的新观察，即外源性UB在β- 肾上腺素能受体刺激的心肌重塑。在人THP 1白血病细胞中，CXCR 4是 被鉴定为细胞外UB的受体。我们的初步数据使用- i）全球的孤立心脏模型 缺血/再灌注（I/R; Langendorff模型）;和ii）小鼠体内心肌I/R损伤现在表明 外源性UB在I/R损伤后心肌重塑中的保护作用。UB治疗 3天后梗死面积减小，心脏炎症反应减少，心功能改善 I/R后在体外，UB处理抑制中性粒细胞的迁移，并增强 巨噬细胞在成人心脏成纤维细胞中，UB处理激活了ERK 1/2， 血管内皮生长因子-A（VEGF-A）。UB与CXCR 4和CXCR 4共免疫沉淀 拮抗作用否定了细胞外UB对ERK 1/2激活和VEGF-A表达的影响。UB 处理增强α-平滑肌肌动蛋白（肌成纤维细胞分化的标志物）表达 和胶原凝胶收缩活性的成纤维细胞，同时减少成纤维细胞迁移到 伤口面积和抑制FBS刺激的细胞增殖。这些观察使我们假设 外源性UB，很可能通过CXCR 4起作用，调节心脏炎症反应， 细胞外基质生物学通过影响嗜中性粒细胞、巨噬细胞和巨噬细胞的表型和/或功能， 成纤维细胞，从而在缺血和I/R后的心肌重塑中发挥心脏保护作用 损伤目的1将在体内研究外源性UB对心肌细胞的治疗潜力， 心肌缺血再灌注损伤后的重构。目的2将在体内研究CXCR 4的作用， 在使用CXCR 4拮抗剂、UB突变体和 细胞类型特异性CXCR 4敲除小鼠。目的3将探讨其细胞和分子机制 外源性UB通过影响心脏炎症反应和细胞外基质生物学， 协调I/R后心脏保护反应。本课题的创新之处在于调查研究 外源性UB在心肌缺血后心肌重塑中的治疗潜力 和I/R损伤（临床相关模型）。研究外源性UB作用的拟定研究 在心脏炎症和细胞外基质生物学中的作用可能揭示新的治疗策略， 的IHD。