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.

脊髓损伤（SCI）导致永久性运动和感觉丧失， 在受伤后几个月持续的炎症加剧。SCI后，单核细胞源性巨噬细胞 （MDM）浸润病变以帮助细胞碎片清除。然而，这种反应正在成为一种双重的- 锋利的剑残留的碎片抑制修复和可塑性，同时通过浸润MDM清除碎片 诱导促炎和损伤表型。清除富含胆固醇的髓鞘碎片 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- 当过量摄取胆固醇时形成的充满大量脂滴（LD）的巨噬细胞 抑制胆固醇代谢。泡沫细胞也驱动动脉粥样硬化和非动脉粥样硬化的慢性炎症。 酒精性脂肪性肝炎（NASH）。泡沫细胞长期存在于受损的脊髓中，并可能导致脊髓损伤。 持续的促炎性损伤环境。然而，它们在慢性炎症状态中的作用很差 明白因此，阐明SCI后泡沫细胞形成的影响是理解SCI后泡沫细胞形成的关键。 MDM对损伤病理学的贡献。初步和已发表的数据将Perilipin 2（Plin 2）确定为关键 在SCI后的浸润性MDM和动脉粥样硬化中的泡沫细胞中差异上调的基因。Plin 2是 在调节胆固醇的形成和储存中是必需的（即，脂滴（LDs）） 脂质代谢物从这些细胞输出或储存在LD中。Plin 2给LD涂上涂层，把它们隔离在 并阻止脂解酶接近其货物。因此，减小Plin 2可以减小LD 积累和减轻SCI后泡沫细胞的形成。在动脉粥样硬化和NASH模型中，Plin 2 缺陷小鼠产生较少的泡沫细胞，并保护免于动脉粥样硬化斑块形成， 肝硬化。为了了解脊髓损伤后MDM中Plin 2上调的作用， 使用LysMCre/lox系统缺失Plin 2。使用这个鼠标模型，这个项目将 （1）使用体外方法确定Plin 2在髓鞘诱导的泡沫细胞形成中的作用，和（2） MDMs中靶向Plin 2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中的细胞特异性Plin 2消融抑制细胞凋亡的假设。 SCI后泡沫细胞形成，抑制炎症，促进功能恢复。如果成功，这个项目 将为CNS巨噬细胞如何代谢髓鞘提供新的见解，并可能提供新的治疗方法。 旨在通过解决慢性椎管内炎症来改善SCI恢复。通过完成这一 培训补助金，PI将接受有关项目管理实施的充分培训， 负责任地开展研究，传播研究结果。该培训将为PI提供 必要的技能，以实现具体的目标，并奠定基础，PI成为一个独立的 在神经创伤领域拥有一个由校外支持的研究组合的医生科学家。

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