The role of macrophage metabolism and age in recovery from spinal cord injury

巨噬细胞代谢和年龄在脊髓损伤恢复中的作用

• 批准号: 10666769
• 负责人: JOHN C GENSEL
• 金额: $ 54.93万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2028-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10666769
• 关键词: 5 year old; Acetyl Coenzyme A; Age; Aging; Anatomy; Animal Model; Anti-Inflammatory Agents; Automobile Driving; Bioenergetics; Cardiovascular Diseases; Catalogs; Chronic; Citric Acid Cycle; Clinical; Data; Diabetes Mellitus; Dichloroacetate; Disease Progression; Dose; Drug Formulations; Evaluation; Fostering; Functional disorder; Gatekeeping; Genetic; Genetic Transcription; Genus Hippocampus; Gliosis; Glucose; Glycolysis; Health; Health Care Costs; Human; Impairment; In Vitro; Incidence; Individual; Inflammation; Inflammatory; Injury; Knockout Mice; Knowledge; Label; Laboratories; Link; Liposomes; Locomotor Recovery; Macrophage; Macrophage Activation; Malignant Neoplasms; Measures; Metabolic; Metabolic Pathway; Metabolic dysfunction; Metabolism; Microglia; Mission; Modeling; Mus; Myeloid Cells; Nervous System Trauma; Neurosciences; Outcome; Oxidative Phosphorylation; Oxygen Consumption; PDH kinase; Paralysed; Pathologic; Pathology; Pathway interactions; Patients; Peripheral; Pharmaceutical Preparations; Population; Public Health; Publishing; Pyruvate; Reaction; Recovery; Recovery of Function; Reporting; Research; Role; Secondary to; Sensory; Spinal Cord Contusions; Spinal cord injury; Techniques; Testing; Therapeutic; Therapeutic Effect; Time; Tissues; Translating; United States National Institutes of Health; Work; age related; aged; axonal sprouting; clinical practice; clinically relevant; design; disability; experimental study; extracellular; immunomodulatory therapies; immunoregulation; improved; in vivo; inhibitor; injury recovery; innovation; insight; juvenile animal; kinase inhibitor; liposomal formulation; metabolic profile; metabolomics; neuroinflammation; neuronal survival; novel; pharmacologic; pyruvate dehydrogenase; repair function; response; single-cell RNA sequencing; stable isotope; therapeutic evaluation; therapeutic target; tissue repair; tool; translational impact; treatment strategy

PROJECT SUMMARY/ABSTRACT The average age at the time of spinal cord injury (SCI) has increased to 50.5 years old in the US. Observations from several independent laboratories demonstrate that inflammation, specifically sustained pro-inflammatory macrophage activation, contributes to age-related SCI deficits. In addition, it was recently discovered that the efficacy of immunomodulatory SCI therapies is age-dependent. There is an urgent need to understand the age-dependent mechanisms of sustained pro-inflammatory macrophage activation in SCI. The purpose of this proposal is to investigate the role of macrophage bioenergetics in age-dependent inflammation and SCI pathophysiology. The central hypothesis is that age-dependent impairments in macrophage metabolism drive pro-inflammatory macrophage activation and contribute to secondary injury after SCI. The premise is that the pyruvate dehydrogenase (PDH) pathway is a key regulator of pro- or anti-inflammatory macrophage activation as a connecting link between glycolysis (pro-inflammatory) or oxidative phosphorylation (OXPHOS, i.e. TCA or Krebs cycle activity; anti-inflammatory). PDH kinase (PDK) regulates PDH thereby serving as the gatekeeper for OXPHOS. The hypothesis to be tested is that PDK inhibition will drive metabolic processes (i.e. increased OXPHOS) required for reparative macrophage activation and improved SCI recovery by PDK. Accordingly, three independent Aims are designed to selectively target macrophage metabolism mechanistically, using chimerization with PDK knockout mice, and therapeutically, using a newly generated liposomal drug formulation of dichloroacetate (DCA), a PDK inhibitor. 4 and 14-month-old mice will undergo T9 contusion SCI to model the current SCI demographic. Aim 1 will identify PDH as a bottleneck for SCI macrophage metabolism using a newly optimized purification approach that allows for isolation of macrophages after SCI and assessment of extracellular acidification (ECAR, i.e. glycolysis) and oxygen consumption (OCR, i.e. OXPHOS) rates using the Seahorse bioanalyzer. Aim 2 will identify metabolic targets for macrophage dysfunction after SCI using state-of-the-art techniques including single-cell RNA-sequencing and in vivo Stable Isotope-Resolved Metabolomics to determine the metabolic profiles of resident microglia and peripherally derived macrophages. Aim 3 will identify PDK inhibition as a therapeutic target to treat SCI through evaluation of anatomic and functional recovery. Completion of the proposed work will identify ways to harness the reparative functions of CNS macrophages and improve clinical practice by refining translational treatment strategies including age as a potential influence in SCI treatment and recovery. Understanding the extent to which metabolic activity regulates macrophage function will provide insight into age-dependent CNS inflammation, thereby advancing the fields of neurotrauma, neuroscience, and aging. Macrophage metabolism is a contributing factor in a host of inflammatory conditions including cardiovascular disease, diabetes, cancer, etc., and the completion of the proposed aims will advance the study of human health on multiple fronts.

项目摘要/摘要 在美国，脊髓损伤时的平均年龄已增加到50.5岁。观察 从几个独立的实验室中表明，炎症，特定持续的促炎性 巨噬细胞激活有助于与年龄有关的SCI缺陷。此外，最近发现 免疫调节科学疗法的功效是年龄依赖的。迫切需要了解 SCI中持续促炎性巨噬细胞激活的年龄依赖性机制。这个目的 提案是研究巨噬细胞生物能力在年龄依赖性炎症和SCI中的作用 病理生理学。中心假设是巨噬细胞代谢中的年龄依赖性损害驱动 促炎性巨噬细胞激活，并在SCI后导致继发性损伤。前提是 丙酮酸脱氢酶（PDH）途径是促或抗炎巨噬细胞激活的关键调节剂 作为糖酵解（促炎）或氧化磷酸化之间的连接联系（Oxphos，即TCA或 克雷布斯周期活动；消炎（药）。 PDH激酶（PDK）调节PDH，从而充当守门人 用于oxphos。要检验的假设是PDK抑制作用将推动代谢过程（即增加 oxphos）需要修复巨噬细胞激活和PDK改善SCI恢复。因此， 三个独立目标旨在使用机理选择性地靶向巨噬细胞代谢 使用新生成的脂质体药物用PDK敲除小鼠进行嵌合 PDK抑制剂二氯乙酸（DCA）的配方。 4个月大的小鼠将接受T9挫伤科学 建模当前的SCI人群。 AIM 1将把PDH识别为Sci巨噬细胞的瓶颈 使用新优化的纯化方法的代谢，该方法允许在SCI后隔离巨噬细胞 以及评估细胞外酸化（ECAR，即糖酵解）和氧气消耗（OCR，即 使用海马生物分析仪的oxphos）。 AIM 2将识别巨噬细胞的代谢靶标 SCI后使用最先进的技术（包括单细胞RNA-severing and Bentable）的功能障碍 同位素分辨的代谢组学，以确定居民小胶质细胞和周围的代谢特征 衍生的巨噬细胞。 AIM 3将确定PDK抑制作用是通过评估治疗SCI的治疗靶标 解剖和功能恢复。拟议工作的完成将确定利用的方法 CNS巨噬细胞的修复功能并通过完善转化处理来改善临床实践 包括年龄在SCI治疗和恢复中的潜在影响在内的策略。了解程度 哪种代谢活性调节巨噬细胞功能将提供对年龄依赖性CNS的洞察力 炎症，从而促进了神经科，神经科学和衰老的领域。巨噬细胞代谢 是在许多炎症状况中的促成因素，包括心血管疾病，糖尿病，癌症， 等等，拟议的目标的完成将在多个方面推进对人类健康的研究。