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: 10265316
• 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/10265316
• 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; 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。 IHD 的严重后果，通常可归因于心肌的窘迫效应 缺血/再灌注（I/R）损伤。心脏炎症和细胞外基质沉积（疤痕）。 形成）是心肌梗死后心脏重塑的重要事件。 这些事件可能为心肌梗死患者带来希望。该提案调查了治疗潜力。 泛素（UB；一种小分子量蛋白质，通常与标记蛋白相关 心肌缺血和 I/R 损伤后心肌重塑中的蛋白酶体降解）。 该提案基于我们的新观察，即外源性 UB 在 β- 中发挥保护作用 在人 THP1 白血病细胞中，CXCR4 是肾上腺素受体刺激的心肌重塑。 我们使用的初步数据确定为细胞外 UB 的受体 - i) 全球分离心脏模型。 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。 减少梗塞面积、减少心脏炎症反应并改善心脏功能 3 天 在体外，UB 治疗抑制中性粒细胞的迁移，并增强吞噬细胞的活性。 在成人心脏成纤维细胞中，UB 治疗激活了 ERK1/2，并增加了表达。 血管内皮生长因子-A (VEGF-A) 与 CXCR4 和 CXCR4 免疫共沉淀。 拮抗作用消除了细胞外 UB 对 ERK1/2 激活和 VEGF-A 表达的影响。 治疗增强 α-平滑肌肌动蛋白（肌成纤维细胞分化的标志物）表达 和成纤维细胞的胶原凝胶收缩活性，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。 外源性 UB 最有可能通过 CXCR4 发挥作用，调节心脏炎症反应 通过影响中性粒细胞、巨噬细胞和细胞外基质生物学的表型和/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 目标 1 将研究外源性 UB 对心肌的体内治疗潜力。 心肌缺血和 I/R 损伤后的重塑将在体内检查 CXCR4 的作用。 使用 CXCR4 拮抗剂、UB 突变体和外源性 UB 调节外源性 UB 的心脏保护作用 Aim 3 将研究细胞类型特异性 CXCR4 敲除小鼠的细胞和分子机制。 外源性 UB 通过影响心脏炎症反应和细胞外基质生物学来 协调缺血再灌注后心脏保护反应。该项目的创新在于调查。 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）。拟议的研究调查了外源性 UB 的作用。 心脏炎症和细胞外基质生物学可能会揭示新的治疗策略 的 IHD。