Duplex miR-223 and Exosomes in Sepsis

败血症中的双链 miR-223 和外泌体

• 批准号: 9195740
• 负责人: Guo-Chang Fan
• 金额: $ 30万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9195740
• 关键词: Affect; Animals; Apoptosis; Attenuated; Blood; Blood Vessels; Bone Marrow; Cardiac; Cardiac Death; Cardiac Myocytes; Cardiomyopathies; Cardiovascular system; Cause of Death; Cells; Cessation of life; Clinical; Clinical Research; Code; Critical Illness; Data; Development; Engineering; Functional disorder; Goals; Heart; Heart failure; Human; Impairment; Inflammation; Inflammation Mediators; Inflammatory; Inflammatory Response; Injection of therapeutic agent; Injury; Interleukin-1; Interleukin-6; Knock-out; Knockout Mice; Knowledge; Lead; Ligands; Ligation; Macrophage Inflammatory Protein-1; Mediating; Mediator of activation protein; Membrane Proteins; Mesenchymal Stem Cells; MicroRNAs; Mission; Modeling; Morbidity - disease rate; Mus; Muscle Cells; Myocardial; Myocardial dysfunction; Myocardium; Nitric Oxide Synthase; Pathway interactions; Patients; Peritoneal; Peritoneal Fluid; Play; Production; Public Health; Puncture procedure; RNA; Reagent; Reducing Agents; Research; Role; STAT3 gene; Semaphorin-3A; Sepsis; Septic Shock; Serum; Signal Pathway; Source; Stress; Study of serum; TNF gene; TNFRSF1A gene; Testing; Therapeutic; Therapeutic Agents; Therapeutic Effect; Therapeutic Intervention; Tissues; Transgenic Mice; Treatment Efficacy; United States National Institutes of Health; Untranslated Regions; Up-Regulation; Work; base; chemokine; cytokine; disability; exosome; improved; insight; interest; macrophage; mortality; mouse model; nanovesicle; novel; novel therapeutics; overexpression; public health relevance; receptor; receptor expression; screening; septic; survival outcome; therapeutic evaluation; tool; transcription factor; translational study

DESCRIPTION (provided by applicant): Cardiovascular dysfunction is a major contributor to sepsis-induced death in critically ill patients. Despite decades of intensive study, the basic mechanisms remain elusive. In particular, therapeutic interventions aimed at a single mediator or pathways of inflammation have failed to improve cardiac function and survival outcome in sepsis. Thus, continuing search for effective therapeutic reagents which target multiple factors is greatly needed. Recent identified microRNAs may provide new targets for effective sepsis therapy. Our latest work has discovered, for example, that: 1) miR-223 (-5p & -3p) are significantly reduced in mouse hearts after severe sepsis; 2) global loss of duplex miR-223 aggravated sepsis-induced cardiac dysfunction and mortality; and 3) miR-223-5p inhibited the expression of TNFR1 and Sema3A (a ligand of TLRs), while miR-223-3p repressed the expression of IL-6, STAT3, MIP-1�MIP-2 in macrophages and myocytes. Given that each of these molecules can potentially contribute to sepsis-induced cardiac dysfunction and mortality, it will be significant to test the effects of global elevation of duplex miR-223 on sepsis-caused injury. Our pilot data also indicate that: 1) lesser amounts of duplex miR-223 are encased within exosomes isolated from the blood of septic mice (referred to as septic exosomes), compared to healthy exosomes and 2) septic exosomes impaired cardiomyocyte contractility and stimulated macrophages to release pro-inflammatory cytokines (i.e. TNF-�IL-6). Thus, it will be important to test whether duplex miR-223 is a critical limiting factor whose reduction contributes to septic exosome-induced detrimental effects on cardiac function and mortality. Finally, an important translational question is raised: are there any positive therapeutic effects of engineering exosomes to contain extra miR-223 on sepsis? In this proposal, we hypothesize that global elevation of duplex miR-223 limits sepsis-induced cardiac dysfunction and mortality through targeting diverse mediators at multiple levels, and loss of duplex miR-223 contributes to septic exosome-triggered cardiac dysfunction. These ideas will be tested by pursuing three specific aims: 1) Using a transgenic mouse model, we will test whether global elevation of duplex miR-223 attenuates sepsis-induced myocardial depression and mortality; 2) Utilizing duplex miR-223-null exosomes and septic exosomes isolated from the blood of miR-223-knockout mice and CLP-operated mice to test whether septic exosome-mediated cardiac dysfunction and mortality is ascribed to the reduction of duplex miR-223; and 3) We will use bone marrow-derived mesenchymal stem cells (MSCs) as a source of miR-223-exosomes to determine the therapeutic effects of duplex-miR-223-engineered exosomes on sepsis-induced cardiac dysfunction and mortality. Together, the proposed studies are expected to unveil a previously unrecognized role of duplex miR-223 in sepsis-induced heart failure. Additionally, they are expected to provide novel insights that lead to the development of original exosome-based therapeutic strategies for reducing septic death.

描述（由申请人提供）：心血管功能障碍是危重患者脓毒症所致死亡的主要原因。尽管经过数十年的深入研究，基本机制仍然难以捉摸。特别是，针对单一介质或炎症途径的治疗干预未能改善脓毒症的心脏功能和生存结果。因此，持续寻找针对多种因素的有效治疗试剂是 非常需要。最近发现的 microRNA 可能为有效的脓毒症治疗提供新的靶点。例如，我们最新的工作发现：1）严重脓毒症后小鼠心脏中的 miR-223（-5p 和 -3p）显着减少； 2) 双链体 miR-223 的整体缺失加剧了脓毒症引起的心功能障碍和死亡率； 3）miR-223-5p抑制TNFR1和Sema3A（TLR配体）的表达，而miR-223-3p抑制巨噬细胞和肌细胞中IL-6、STAT3、MIP-1�MIP-2的表达。鉴于这些分子中的每一个都可能导致脓毒症引起的心脏功能障碍和死亡，因此测试双链体 miR-223 整体升高对脓毒症引起的损伤的影响将具有重要意义。我们的试验数据还表明：1）与健康外泌体相比，从脓毒症小鼠血液中分离的外泌体（称为脓毒症外泌体）中包裹的双链体 miR-223 含量较少，2）脓毒症外泌体损害心肌细胞收缩性并刺激巨噬细胞释放促炎细胞因子（即 TNF-αIL-6）。因此，测试双链体 miR-223 是否是一个关键的限制因素非常重要，其减少会导致脓毒症外泌体对心脏功能和死亡率产生不利影响。最后，提出了一个重要的转化问题：改造外泌体以包含额外的 miR-223 对脓毒症有任何积极的治疗作用吗？在该提议中，我们假设双链体 miR-223 的整体升高通过在多个水平上靶向不同的介质来限制脓毒症引起的心脏功能障碍和死亡率，而双链体 miR-223 的缺失会导致脓毒症外泌体触发的心脏功能障碍。这些想法将通过追求三个具体目标来检验：1）使用转基因小鼠模型，我们将测试双链体 miR-223 的整体升高是否会减轻脓毒症引起的心肌抑制和死亡率； 2)利用从miR-223敲除小鼠和CLP手术小鼠的血液中分离出的双链体miR-223无效外泌体和脓毒症外泌体来测试脓毒症外泌体介导的心脏功能障碍和死亡率是否归因于双链体miR-223的减少； 3) 我们将使用骨髓间充质干细胞（MSC）作为 miR-223 外泌体的来源，以确定双链 miR-223 工程外泌体对脓毒症引起的心功能障碍和死亡率的治疗效果。总之，拟议的研究有望揭示双链体 miR-223 在脓毒症诱发的心力衰竭中先前未被认识的作用。此外，他们有望提供新颖的见解，从而开发出基于外泌体的原创治疗策略，以减少脓毒症死亡。