The Role of Perilipin 2 in Macrophages after Experimental Spinal Cord Injury

Perilipin 2 在实验性脊髓损伤后巨噬细胞中的作用

• 批准号: 10683728
• 负责人: Ethan Phares Glaser
• 金额: $ 5.27万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-09 至 2026-08-08
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10683728
• 关键词: Ablation; Acute; Alzheimer' s Disease; Arterial Fatty Streak; Atherosclerosis; Bone Marrow; Cells; Cholesterol; Cholesterol Homeostasis; Chronic; Cirrhosis; Custom; Cytosol; Data; Disease; Environment; Enzyme-Linked Immunosorbent Assay; Enzymes; Extramural Activities; Family; Fluorescent in Situ Hybridization; Foam Cells; Foundations; Functional disorder; Gene Expression; Genes; Genetic; Grant; Health Care Costs; Immunofluorescence Immunologic; In Vitro; Individual; Infiltration; Inflammation; Inflammatory; Injury; Interleukin-1 beta; Interleukin-6; Lesion; Leukocytes; Lipid-Laden Macrophage; Lipids; Locomotor Recovery; Macrophage; Mediating; Metabolism; Microscopy; Modeling; Morphology; Motor; Mus; Myelin; Myeloid Cells; Nervous System Trauma; Paralysed; Pathology; Pathway interactions; Phagocytosis; Phenotype; Physicians; Process; Production; Publishing; Quantitative Reverse Transcriptase PCR; Recovery; Recovery of Function; Research Support; Role; Scientist; Sensory; Site; Sorting; Spinal Cord; Spinal cord injury; Stains; Stimulus; System; Testing; Time; Tissues; Training; Transgenic Model; Up-Regulation; Visualization; Western Blotting; Work; collected works; cytokine; design; experimental study; histological stains; improved; in vitro Model; inflammatory milieu; injured; injury recovery; insight; lipid metabolism; molecular sequence database; monocyte; mouse model; nano-string; neuroinflammation; new therapeutic target; nonalcoholic steatohepatitis; novel; perilipin; prevent; repaired; response; responsible research conduct; single-cell RNA sequencing; skills; therapeutic target; uptake

PROJECT SUMMARY/ABSTRACT Spinal cord injury (SCI) leads to permanent motor and sensory loss that is exacerbated by persistent inflammation months after the injury. After SCI, monocyte-derived macrophages (MDMs) infiltrate the lesion to aid in cellular debris clearance. However, this response is emerging as a double- edged sword. Lingering debris inhibits repair and plasticity while clearance of the debris by infiltrating MDMs induces a proinflammatory and damaging phenotype. Clearance of cholesterol-rich myelin debris causes MDMs to resemble proinflammatory foam cells both phenotypically and morphologically. Foam cells are lipid- laden macrophages with numerous lipid droplets (LDs) that form when excessive cholesterol uptake overwhelms cholesterol metabolism. Foam cells also drive chronic inflammation in atherosclerosis and non- alcoholic steatohepatitis (NASH). Foam cells persist chronically in the injured cord and may contribute to the sustained proinflammatory lesion environment. However, their role in the chronic inflammatory state is poorly understood. Therefore, elucidating the effect of foam cell formation after SCI is integral to understanding the contribution of MDMs to injury pathology. Preliminary and published data identify Perilipin 2 (Plin2) as a key differentially upregulated gene in both infiltrating MDMs after SCI and foam cells in atherosclerosis. Plin2 is essential in regulating the formation and storage of cholesterol (i.e., lipid droplets (LDs)) in macrophages as lipid metabolites are either exported from these cells or stored in LDs. Plin2 coats LDs, sequesters them in the cytosol and prevents lipolytic enzymes from accessing their cargo. Reducing Plin2, may, therefore, reduce LD accumulation and mitigate foam cell formation after SCI. In models of atherosclerosis and NASH, Plin2 deficient mice produced fewer foam cells and were protected from atherosclerotic plaque formation and cirrhosis, respectively. To understand the effects of Plin2 upregulation in MDMs after SCI a novel targeted deletion of Plin2 using a LysMCre/lox system will be employed. Using this mouse model, this project will determine (1) the role of Plin2 in myelin-induced foam cell formation using an in vitro approach and (2) the effects of targeted Plin2 deletion in MDMs on foam cell formation, inflammation, and locomotor recovery after experimental. These experiments will test the hypothesis that cell-specific Plin2 ablation in MDMs suppresses foam cell formation after SCI, inhibits inflammation, and promotes functional recovery. If successful, this project will provide novel insight into how CNS macrophages metabolize myelin and may provide new therapeutic targets to improve SCI recovery by resolving chronic intraspinal inflammation. Through the completion of this training grant, the PI will receive ample training regarding the implementation of project management, responsible conduct of research, and the dissemination of findings. This training will provide the PI with the skillset necessary to carry out the specific aims and lay the foundation for the PI to become an independent physician-scientist with an extramurally supported research portfolio in the field of neurotrauma.

项目摘要/摘要 脊髓损伤 (SCI) 会导致永久性运动和感觉丧失， 受伤后几个月持续炎症加剧。 SCI 后，单核细胞来源的巨噬细胞 (MDM) 渗透病变部位以帮助清除细胞碎片。然而，这种反应正在成为一种双重反应 有刃的剑。残留的碎片会抑制修复和可塑性，同时通过渗透 MDM 清除碎片 诱导促炎和破坏性表型。清除富含胆固醇的髓磷脂碎片的原因 MDM 在表型和形态上都类似于促炎泡沫细胞。泡沫细胞是脂质 充满大量脂滴 (LD) 的巨噬细胞在过量摄入胆固醇时形成 压倒胆固醇代谢。泡沫细胞还会导致动脉粥样硬化和非慢性炎症 酒精性脂肪肝炎（NASH）。泡沫细胞长期存在于受伤的脊髓中，可能有助于 持续的促炎病变环境。然而，它们在慢性炎症状态中的作用很差 明白了。因此，阐明 SCI 后泡沫细胞形成的影响对于理解 SCI 后泡沫细胞形成的影响至关重要。 MDM 对损伤病理学的贡献。初步和已发表的数据将 Perilipin 2 (Plin2) 确定为关键 SCI 后浸润性 MDM 和动脉粥样硬化泡沫细胞中的基因差异上调。 Plin2 是 对于调节巨噬细胞中胆固醇（即脂滴（LD））的形成和储存至关重要 脂质代谢物要么从这些细胞中输出，要么储存在 LD 中。 Plin2 包裹 LD，将它们隔离在 细胞质并阻止脂肪分解酶接触其货物。因此，减少 Plin2 可能会减少 LD SCI 后的积累并减轻泡沫细胞的形成。在动脉粥样硬化和 NASH 模型中，Plin2 有缺陷的小鼠产生的泡沫细胞较少，并且免受动脉粥样硬化斑块形成的影响 分别是肝硬化。为了了解 SCI 后 Plin2 上调对 MDM 的影响，一种新的靶向药物 将使用 LysMCre/lox 系统删除 Plin2。使用该鼠标模型，该项目将 使用体外方法确定 (1) Plin2 在髓磷脂诱导的泡沫细胞形成中的作用，以及 (2) MDM 中靶向 Plin2 缺失对泡沫细胞形成、炎症和运动恢复的影响 实验性的。这些实验将检验 MDM 中细胞特异性 Plin2 消融抑制的假设 SCI后泡沫细胞形成，抑制炎症，促进功能恢复。如果成功的话，这个项目 将为中枢神经系统巨噬细胞如何代谢髓磷脂提供新的见解，并可能提供新的治疗方法 目标是通过解决慢性脊柱内炎症来改善 SCI 恢复。通过本次的完成 培训补助金，PI将接受有关项目管理实施的充分培训， 负责任地进行研究并传播研究结果。该培训将为 PI 提供 实现特定目标所需的技能，并为PI成为独立的人奠定基础 医生兼科学家，在神经创伤领域拥有校外支持的研究组合。

项目成果

Effects of Acute Ethanol Intoxication on Spinal Cord Injury Outcomes in Female Mice.

• DOI: 10.1089/neu.2023.0077
• 发表时间: 2023-12
• 期刊: JOURNAL OF NEUROTRAUMA
• 影响因子: 4.2
• 作者: Glaser, Ethan P.;Stewart, Andrew N.;Jagielo-Miller, Julia E.;Bailey, Caleb S.;Prendergast, Mark A.;Gensel, John C.
• 通讯作者: Gensel, John C.

Ethanol sustains phosphorylated tau protein in the cultured neonatal rat hippocampus: Implications for fetal alcohol spectrum disorders.

• DOI: 10.1016/j.alcohol.2022.07.007
• 发表时间: 2022-09
• 期刊: ALCOHOL
• 影响因子: 2.3
• 作者: Bailey, Caleb Seth;Jagielo-Miller, Julia Elaine;Keller, Peggy Sue;Glaser, Ethan Phares;Wilcox, Abigail Lowe;Prendergast, Mark Alan
• 通讯作者: Prendergast, Mark Alan