mtDNA damage and DAMPs in multiple organ dysfunction syndrome

多器官功能障碍综合征中的 mtDNA 损伤和 DAMP

• 批准号: 9921454
• 负责人: MARK N GILLESPIE
• 金额: $ 43.86万
• 依托单位: UNIVERSITY OF SOUTH ALABAMA
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-05-01 至 2023-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9921454
• 关键词: Address; Animal Model; Biological; Biological Markers; Blood Circulation; Characteristics; Chimeric Proteins; Clinical; Clinical Management; DNA Damage; DNA Repair Enzymes; Development; Distant; Drug Targeting; Evolution; Family suidae; Functional disorder; Goals; Hemorrhage; Inflammatory; Injury; Interruption; Intervention; Ischemia; Laboratories; Length; Link; Liver; Mediating; Mesentery; Mitochondria; Mitochondrial DNA; Modeling; Molecular; Multiple Organ Failure; Observational Study; Organ; Organ failure; Outcome; Pathway interactions; Patients; Pattern; Pattern Formation; Pharmaceutical Preparations; Pharmacology; Physiological; Play; Prevention; Production; Reperfusion Therapy; Reporting; Research; Rodent; Rodent Model; Role; Series; Source; System; Testing; Tissues; Translating; Translations; Trauma; Variant; cell type; clinical application; clinical practice; clinically relevant; cytotoxic; cytotoxicity; human subject; innovation; insight; intestinal epithelium; laboratory experiment; lymphatic drainage; novel; operation; oxidative damage; predictive marker; repaired; severe injury; targeted treatment

Management of severely injured patients is challenging because Multiple Organ Dysfunction Syndrome may advance relentlessly even if the initial insult is controlled. However, a series of reports point to the prospect that mitochondrial (mt)-associated pathways play a central role. Specifically, it has been discovered that oxidative mtDNA damage is both cytotoxic and leads to its fragmentation into proinflammatory mtDNA Damage Associated Molecular Patterns with the potential to disseminate injury to distant organs. Against this background, the goal of this project is to provide insight into the origin, characteristics, and biological effects of mtDNA DAMPs in the setting of trauma-related MODS as a prelude for translating mtDNA- directed therapies into clinical application. We will use a clinically-relevant porcine model of MODS induced by hemorrhage with truncal ischemia and reperfusion to address three Aims. Because conventional strategies for analysis of circulating mtDNA DAMPs use PCR to quantify sequences of about 200 bp in length, it is likely that the most prevalent or biologically relevant mtDNA DAMP species have not been identified. In addition, there are tissue-specific differences in mtDNA sequences that may dictate sequence characteristics of circulating mtDNA DAMPs. Accordingly, Aim 1 will define sequence characteristics of mtDNA DAMPs released during the evolution of trauma-related MODS and test the hypothesis that unique variant signatures of circulating mtDNA can be traced to specific organs and that fail. The second aim addresses the origin of mtDNA fragments accumulating in the circulation after trauma. In this regard, it has been known for decades that interuption of mesenteric lymphatic drainage forestalls MODS, thus supporting the concept that the liver- gut-mesenteric axis could be a major source of circulating mtDNA DAMPs, perhaps stimulating mtDNA DAMP production in other organs. Aim 2 will therefore test the hypotheses that in trauma, mtDNA DAMPs are present in the mesenteric lymphatic drainage and that an intact mesenteric lymphatic drainage system is required for systemic mtDNA DAMP accumulation and MODS. Finally, prevention or reversal of mtDNA damage with novel fusion protein constructs targeting DNA repair enzymes to mitochondria and pharmacological enhancement of mtDNA DAMP degradation with a repurposed agent, DNase1, forestalls IR injury in rodents. Importantly, however, neither of these strategies have been explored in a clinically-relevant animal model. As a consequence, critical mechanistic insight, particularly the purported operation of a feed- forward pathway linking mtDNA damage to mtDNA DAMP production, is unavailable. Accordingly, to provide information needed for translation of mtDNA-directed therapies into clinical application, Aim 3 will use test the hypothesis that mt-targeted Ogg1 and DNase1, given alone or in combination, alter disposition of circulating mtDNA DAMPs and suppress MODS.

严重创伤患者的处理是具有挑战性的，因为多器官功能障碍综合征可能 即使最初的侮辱得到了控制，也要坚持不懈地前进。然而，一系列报告指出了这一前景 线粒体(Mt)相关通路起着核心作用。具体地说，人们已经发现， 氧化性mtDNA损伤既有细胞毒性，又会导致其断裂为促炎性mtDNA损伤 与可能将损伤传播到远处器官的相关分子模式。反对这一点 背景，这个项目的目标是提供对起源、特征和生物学的洞察 线粒体DNA抑制在创伤相关多器官功能障碍综合征中的作用 指导治疗进入临床应用。我们将使用临床相关的多器官功能障碍综合征猪模型 通过出血合并躯干缺血再灌流达到三个目的。因为常规策略 为了分析循环中的线粒体DNA损伤，使用聚合酶链式反应来量化大约200个碱基的序列，很可能 最普遍的或与生物相关的线粒体DNA潮湿物种尚未确定。此外, 线粒体DNA序列中存在组织特异性差异，这可能决定了 循环中的线粒体DNA受到抑制。因此，目标1将定义释放的mtDNA阻滞剂的序列特征 在创伤相关多器官功能障碍的演变过程中，并检验以下假设 循环中的线粒体DNA可以追溯到特定的器官，但这是失败的。第二个目标是解决 线粒体DNA片段在创伤后循环中积聚。在这方面，它已经被知道了几十年 肠系膜淋巴引流的阻断阻止了MODS，从而支持了肝脏- 肠道-肠系膜轴可能是循环线粒体DNA抑制的主要来源，可能刺激线粒体DNA抑制 其他器官的生产。因此，《目标2》将检验以下假设：在创伤中，线粒体DNA抑制物 存在于肠系膜淋巴引流中，且完整的肠系膜淋巴引流系统 全身性线粒体DNA潮湿积累和多器官功能障碍综合征所必需的。最后，防止或逆转线粒体DNA 靶向DNA修复酶的新型融合蛋白构建物对线粒体和 改良剂DNase1对线粒体DNA抑制降解的药理促进作用 啮齿动物的伤害。然而，重要的是，这两种策略都没有在临床相关的研究中得到探索。 动物模型。因此，批判性的机械洞察力，特别是所谓的馈送操作- 将线粒体DNA损伤与线粒体DNA抑制产生联系起来的正向途径是不可用的。因此，为了提供 将线粒体DNA导向疗法转化为临床应用所需的信息，Aim 3将使用测试 假设MT靶向Ogg1和DNase1单独或联合给药，改变循环的处置 线粒体DNA抑制和抑制MODS。