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Amo-Aparicio J, Dinarello CA, Lopez-Vales R. Metabolic reprogramming of the inflammatory response in the nervous system: the crossover between inflammation and metabolism. Neural Regen Res 2024; 19:2189-2201. [PMID: 38488552 PMCID: PMC11034585 DOI: 10.4103/1673-5374.391330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 10/25/2023] [Accepted: 11/13/2023] [Indexed: 04/24/2024] Open
Abstract
Metabolism is a fundamental process by which biochemicals are broken down to produce energy (catabolism) or used to build macromolecules (anabolism). Metabolism has received renewed attention as a mechanism that generates molecules that modulate multiple cellular responses. This was first identified in cancer cells as the Warburg effect, but it is also present in immunocompetent cells. Studies have revealed a bidirectional influence of cellular metabolism and immune cell function, highlighting the significance of metabolic reprogramming in immune cell activation and effector functions. Metabolic processes such as glycolysis, oxidative phosphorylation, and fatty acid oxidation have been shown to undergo dynamic changes during immune cell response, facilitating the energetic and biosynthetic demands. This review aims to provide a better understanding of the metabolic reprogramming that occurs in different immune cells upon activation, with a special focus on central nervous system disorders. Understanding the metabolic changes of the immune response not only provides insights into the fundamental mechanisms that regulate immune cell function but also opens new approaches for therapeutic strategies aimed at manipulating the immune system.
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Affiliation(s)
| | | | - Ruben Lopez-Vales
- Institute of Neurosciences, and Department Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Bellaterra, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, Spain
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2
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Zhou W, He J, Shen G, Liu Y, Zhao P, Li J. TREM2-dependent activation of microglial cell protects photoreceptor cell during retinal degeneration via PPARγ and CD36. Cell Death Dis 2024; 15:623. [PMID: 39187498 PMCID: PMC11347571 DOI: 10.1038/s41419-024-07002-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 08/09/2024] [Accepted: 08/13/2024] [Indexed: 08/28/2024]
Abstract
Retinal degeneration is a collection of devastating conditions with progressive loss of vision which often lead to blindness. Research on retinal microglial cells offers great therapeutic potential in deterring the progression of degeneration. This study explored the mechanisms underlying the TREM2-mediated protective function of activated microglial cells during retinal degeneration. N-methyl-N-nitrosourea (MNU)-induced retinal degeneration was established in C57BL/6 J (WT) and Trem2 knockout (Trem2-/-) mice. We discovered that MNU treatment led to the concurrent processes of photoreceptor apoptosis and microglia infiltration. A significant upregulation of disease-associated microglia signature genes was observed during photoreceptor degeneration. Following MNU treatment, Trem2-/- mice showed exacerbated photoreceptor cell death, decreased microglia migration and phagocytosis, reduced microglial PPARγ activation and CD36 expression. Pharmaceutical activation of PPARγ promoted microglial migration, ameliorated photoreceptor degeneration and restored CD36 expression in MNU-treated Trem2-/- mice. Inhibition of CD36 activity worsened photoreceptor degeneration in MNU-treated WT mice. Our findings suggested that the protective effect of microglia during retinal degeneration was dependent on Trem2 expression and carried out via the activation of PPARγ and the consequent upregulation of CD36 expression. Our study linked TREM2 signaling with PPARγ activation, and provided a potential therapeutic target for the management of retinal degeneration.
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Affiliation(s)
- Wenchuan Zhou
- Department of Ophthalmology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China
| | - Jincan He
- Department of Ophthalmology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China
| | - Guiyan Shen
- Institute of Traditional Chinese Medicine and Stem Cell Research, College of Basic Medical Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
| | - Ya Liu
- Institute of Traditional Chinese Medicine and Stem Cell Research, College of Basic Medical Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
| | - Peiquan Zhao
- Department of Ophthalmology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China.
| | - Jing Li
- Department of Ophthalmology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China.
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3
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Cleland NRW, Bruce KD. Fatty acid sensing in the brain: The role of glial-neuronal metabolic crosstalk and horizontal lipid flux. Biochimie 2024; 223:166-178. [PMID: 35998849 DOI: 10.1016/j.biochi.2022.08.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 07/01/2022] [Accepted: 08/17/2022] [Indexed: 11/15/2022]
Abstract
The central control of energy homeostasis is a regulatory axis that involves the sensing of nutrients, signaling molecules, adipokines, and neuropeptides by neurons in the metabolic centers of the hypothalamus. However, non-neuronal glial cells are also abundant in the hypothalamus and recent findings have underscored the importance of the metabolic crosstalk and horizontal lipid flux between glia and neurons to the downstream regulation of systemic metabolism. New transgenic models and high-resolution analyses of glial phenotype and function have revealed that glia sit at the nexus between lipid metabolism and neural function, and may markedly impact the brain's response to dietary lipids or the supply of brain-derived lipids. Glia comprise the main cellular compartment involved in lipid synthesis, lipoprotein production, and lipid processing in the brain. In brief, tanycytes provide an interface between peripheral lipids and neurons, astrocytes produce lipoproteins that transport lipids to neurons and other glia, oligodendrocytes use brain-derived and dietary lipids to myelinate axons and influence neuronal function, while microglia can remove unwanted lipids in the brain and contribute to lipid re-utilization through cholesterol efflux. Here, we review recent findings regarding glial-lipid transport and highlight the specific molecular factors necessary for lipid processing in the brain, and how dysregulation of glial-neuronal metabolic crosstalk contributes to imbalanced energy homeostasis. Furthering our understanding of glial lipid metabolism will guide the design of future studies that target horizontal lipid processing in the brain to ameliorate the risk of developing obesity and metabolic disease.
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Affiliation(s)
- Nicholas R W Cleland
- Division of Endocrinology Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Kimberley D Bruce
- Division of Endocrinology Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA.
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Ma H, Ou ZL, Alaeiilkhchi N, Cheng YQ, Chen K, Chen JY, Guo RQ, He MY, Tang SY, Zhang X, Huang ZP, Liu J, Liu J, Zhu QA, Huang ZC, Jiang H. MiR-223 enhances lipophagy by suppressing CTSB in microglia following lysolecithin-induced demyelination in mice. Lipids Health Dis 2024; 23:194. [PMID: 38909243 PMCID: PMC11193262 DOI: 10.1186/s12944-024-02185-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 06/13/2024] [Indexed: 06/24/2024] Open
Abstract
BACKGROUND Lipid droplet (LD)-laden microglia is a key pathological hallmark of multiple sclerosis. The recent discovery of this novel microglial subtype, lipid-droplet-accumulating microglia (LDAM), is notable for increased inflammatory factor secretion and diminished phagocytic capability. Lipophagy, the autophagy-mediated selective degradation of LDs, plays a critical role in this context. This study investigated the involvement of microRNAs (miRNAs) in lipophagy during demyelinating diseases, assessed their capacity to modulate LDAM subtypes, and elucidated the potential underlying mechanisms involved. METHODS C57BL/6 mice were used for in vivo experiments. Two weeks post demyelination induction at cervical level 4 (C4), histological assessments and confocal imaging were performed to examine LD accumulation in microglia within the lesion site. Autophagic changes were observed using transmission electron microscopy. miRNA and mRNA multi-omics analyses identified differentially expressed miRNAs and mRNAs under demyelinating conditions and the related autophagy target genes. The role of miR-223 in lipophagy under these conditions was specifically explored. In vitro studies, including miR-223 upregulation in BV2 cells via lentiviral infection, validated the bioinformatics findings. Immunofluorescence staining was used to measure LD accumulation, autophagy levels, target gene expression, and inflammatory mediator levels to elucidate the mechanisms of action of miR-223 in LDAM. RESULTS Oil Red O staining and confocal imaging revealed substantial LD accumulation in the demyelinated spinal cord. Transmission electron microscopy revealed increased numbers of autophagic vacuoles at the injury site. Multi-omics analysis revealed miR-223 as a crucial regulatory gene in lipophagy during demyelination. It was identified that cathepsin B (CTSB) targets miR-223 in autophagy to integrate miRNA, mRNA, and autophagy gene databases. In vitro, miR-223 upregulation suppressed CTSB expression in BV2 cells, augmented autophagy, alleviated LD accumulation, and decreased the expression of the inflammatory mediator IL-1β. CONCLUSION These findings indicate that miR-223 plays a pivotal role in lipophagy under demyelinating conditions. By inhibiting CTSB, miR-223 promotes selective LD degradation, thereby reducing the lipid burden and inflammatory phenotype in LDAM. This study broadens the understanding of the molecular mechanisms of lipophagy and proposes lipophagy induction as a potential therapeutic approach to mitigate inflammatory responses in demyelinating diseases.
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Grants
- No.81902217 National Natural Science Foundation of China
- No.81902217 National Natural Science Foundation of China
- No.81902217 National Natural Science Foundation of China
- No.81902217 National Natural Science Foundation of China
- No.81902217 National Natural Science Foundation of China
- No.81902217 National Natural Science Foundation of China
- No.81902217 National Natural Science Foundation of China
- No.81902217 National Natural Science Foundation of China
- No.81902217 National Natural Science Foundation of China
- No.81902217 National Natural Science Foundation of China
- No.81902217 National Natural Science Foundation of China
- No.81902217 National Natural Science Foundation of China
- No.81902217 National Natural Science Foundation of China
- No.81902217 National Natural Science Foundation of China
- No. 81972064 National Natural Science Foundation of China
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- 2020A1515011415 Natural Science Foundation of Guangdong Province
- 2023A1515010565 Natural Science Foundation of Guangdong Province
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- No.2023A024 President Foundation of Nanfang Hospital, Southern Medical University
- 202102021244 Guangzhou Science and Technology Plan Project
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Affiliation(s)
- Hao Ma
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Zhi-Lin Ou
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Nima Alaeiilkhchi
- International Collaboration on Repair Discoveries (ICORD), Blusson Spinal Cord Centre, University of British Columbia, Vancouver, Canada
| | - Yong-Quan Cheng
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Kai Chen
- The First School of Clinical Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Jia-Yu Chen
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Ru-Qin Guo
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Min-Yue He
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Shi-Yi Tang
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Xin Zhang
- Department of Laboratory Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Zhi-Ping Huang
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Junhao Liu
- Division of Spine Surgery, Department of Orthopaedics, Guangzhou First People's Hospital, School of Medicine, South China University of Technology, Guangzhou, 51000, China
| | - Jie Liu
- The 3rd Affiliated Hospital of Xinxiang Medical University, Henan, China
| | - Qing-An Zhu
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Zu-Cheng Huang
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China.
| | - Hui Jiang
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China.
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Fitzpatrick JMK, O'Riordan D, Downer EJ. Cannflavin A inhibits TLR4-induced chemokine and cytokine expression in human macrophages. Nat Prod Res 2024:1-7. [PMID: 38780010 DOI: 10.1080/14786419.2024.2358382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 05/14/2024] [Indexed: 05/25/2024]
Abstract
Cannflavin A (CFL-A), a flavonoid present in the hemp plant Cannabis sativa L. (C. sativa), has anti-inflammatory and neuroprotective capacity. Research continues to elucidate the anti-inflammatory effects of components of C. sativa, with evidence that plant-derived cannabinoids and terpenes can mediate anti-inflammatory activity by targeting toll-like receptor (TLR) signalling, the sensors of pathogen-associated molecules. This study set out to determine if TLR-mediated inflammatory signalling is a CFL-A target using the endotoxin lipopolysaccharide (LPS) to induce TLR4 signalling in human THP-1-derived macrophages. TLR4 activation promoted the production of the chemokine CXCL10 and cytokines IL-1β and TNFα. Treatment with CFL-A dose-dependently attenuated TLR4-induced CXCL10 and IL-1β secretion, with our findings also indicating that the inhibitory effects of CFL-A on chemokine/cytokine secretion are in line with an NF-κB inhibitor. This study highlights TLR4 signalling as a cannflavin target in macrophages.
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Affiliation(s)
- John-Mark K Fitzpatrick
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | | | - Eric J Downer
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland
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6
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Huang Z, Jordan JD, Zhang Q. Myelin Pathology in Alzheimer's Disease: Potential Therapeutic Opportunities. Aging Dis 2024; 15:698-713. [PMID: 37548935 PMCID: PMC10917545 DOI: 10.14336/ad.2023.0628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 06/28/2023] [Indexed: 08/08/2023] Open
Abstract
Alzheimer's disease (AD) is an age-related neurodegenerative disease characterized by memory loss and cognitive decline. Despite significant efforts over several decades, our understanding of the pathophysiology of this disease is still incomplete. Myelin is a multi-layered membrane structure ensheathing neuronal axons, which is essential for the fast and effective propagation of action potentials along the axons. Recent studies highlight the critical involvement of myelin in memory consolidation and reveal its vulnerability in various pathological conditions. Notably, apart from the classic amyloid hypothesis, myelin degeneration has been proposed as another critical pathophysiological feature of AD, which could occur prior to the development of amyloid pathology. Here, we review recent works supporting the critical role of myelin in cognition and myelin pathology during AD progression, with a focus on the mechanisms underlying myelin degeneration in AD. We also discuss the complex intersections between myelin pathology and typical AD pathophysiology, as well as the therapeutic potential of pro-myelinating approaches for this disease. Overall, these findings implicate myelin degeneration as a critical contributor to AD-related cognitive deficits and support targeting myelin repair as a promising therapeutic strategy for AD.
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Affiliation(s)
- Zhihai Huang
- Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, LA 71103 USA
| | - J. Dedrick Jordan
- Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, LA 71103 USA
| | - Quanguang Zhang
- Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, LA 71103 USA
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Wang XX, Li ZH, Du HY, Liu WB, Zhang CJ, Xu X, Ke H, Peng R, Yang DG, Li JJ, Gao F. The role of foam cells in spinal cord injury: challenges and opportunities for intervention. Front Immunol 2024; 15:1368203. [PMID: 38545108 PMCID: PMC10965697 DOI: 10.3389/fimmu.2024.1368203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 02/22/2024] [Indexed: 04/17/2024] Open
Abstract
Spinal cord injury (SCI) results in a large amount of tissue cell debris in the lesion site, which interacts with various cytokines, including inflammatory factors, and the intrinsic glial environment of the central nervous system (CNS) to form an inhibitory microenvironment that impedes nerve regeneration. The efficient clearance of tissue debris is crucial for the resolution of the inhibitory microenvironment after SCI. Macrophages are the main cells responsible for tissue debris removal after SCI. However, the high lipid content in tissue debris and the dysregulation of lipid metabolism within macrophages lead to their transformation into foamy macrophages during the phagocytic process. This phenotypic shift is associated with a further pro-inflammatory polarization that may aggravate neurological deterioration and hamper nerve repair. In this review, we summarize the phenotype and metabolism of macrophages under inflammatory conditions, as well as the mechanisms and consequences of foam cell formation after SCI. Moreover, we discuss two strategies for foam cell modulation and several potential therapeutic targets that may enhance the treatment of SCI.
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Affiliation(s)
- Xiao-Xin Wang
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - Ze-Hui Li
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - Hua-Yong Du
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - Wu-Bo Liu
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
- Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Chun-Jia Zhang
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - Xin Xu
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - Han Ke
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
- Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Run Peng
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - De-Gang Yang
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - Jian-Jun Li
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
- Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
- Institute of Rehabilitation Medicine, China Rehabilitation Research Center, Beijing, China
| | - Feng Gao
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
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8
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Garcia Corrales AV, Verberk SGS, Haidar M, Grajchen E, Dehairs J, Vanherle S, Loix M, Weytjens T, Gervois P, Matsuzaka T, Lambrichts I, Swinnen JV, Bogie JFJ, Hendriks JJA. Fatty acid elongation by ELOVL6 hampers remyelination by promoting inflammatory foam cell formation during demyelination. Proc Natl Acad Sci U S A 2023; 120:e2301030120. [PMID: 37669365 PMCID: PMC10500284 DOI: 10.1073/pnas.2301030120] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 07/24/2023] [Indexed: 09/07/2023] Open
Abstract
A hallmark of multiple sclerosis (MS) is the formation of multiple focal demyelinating lesions within the central nervous system (CNS). These lesions mainly consist of phagocytes that play a key role in lesion progression and remyelination, and therefore represent a promising therapeutic target in MS. We recently showed that unsaturated fatty acids produced by stearoyl-CoA desaturase-1 induce inflammatory foam cell formation during demyelination. These fatty acids are elongated by the "elongation of very long chain fatty acids" proteins (ELOVLs), generating a series of functionally distinct lipids. Here, we show that the expression and activity of ELOVLs are altered in myelin-induced foam cells. Especially ELOVL6, an enzyme responsible for converting saturated and monounsaturated C16 fatty acids into C18 species, was found to be up-regulated in myelin phagocytosing phagocytes in vitro and in MS lesions. Depletion of Elovl6 induced a repair-promoting phagocyte phenotype through activation of the S1P/PPARγ pathway. Elovl6-deficient foamy macrophages showed enhanced ABCA1-mediated lipid efflux, increased production of neurotrophic factors, and reduced expression of inflammatory mediators. Moreover, our data show that ELOVL6 hampers CNS repair, as Elovl6 deficiency prevented demyelination and boosted remyelination in organotypic brain slice cultures and the mouse cuprizone model. These findings indicate that targeting ELOVL6 activity may be an effective strategy to stimulate CNS repair in MS and other neurodegenerative diseases.
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Affiliation(s)
- Aida V. Garcia Corrales
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek3590, Belgium
| | - Sanne G. S. Verberk
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek3590, Belgium
| | - Mansour Haidar
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek3590, Belgium
| | - Elien Grajchen
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek3590, Belgium
| | - Jonas Dehairs
- Department of Oncology, Laboratory of Lipid Metabolism and Cancer, Leuven Cancer Institute, University of Leuven, Leuven3000, Belgium
| | - Sam Vanherle
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek3590, Belgium
| | - Melanie Loix
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek3590, Belgium
| | - Tine Weytjens
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek3590, Belgium
| | - Pascal Gervois
- Department of Cardiology and Organ Systems, Biomedical Research Institute, Hasselt University, Diepenbeek3590, Belgium
| | - Takashi Matsuzaka
- Department of Internal Medicine (Endocrinology and Metabolism), Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki305-8575, Japan
| | - Ivo Lambrichts
- Department of Cardiology and Organ Systems, Biomedical Research Institute, Hasselt University, Diepenbeek3590, Belgium
| | - Johannes V. Swinnen
- Department of Oncology, Laboratory of Lipid Metabolism and Cancer, Leuven Cancer Institute, University of Leuven, Leuven3000, Belgium
| | - Jeroen F. J. Bogie
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek3590, Belgium
| | - Jerome J. A. Hendriks
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek3590, Belgium
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9
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Distéfano-Gagné F, Bitarafan S, Lacroix S, Gosselin D. Roles and regulation of microglia activity in multiple sclerosis: insights from animal models. Nat Rev Neurosci 2023:10.1038/s41583-023-00709-6. [PMID: 37268822 DOI: 10.1038/s41583-023-00709-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/28/2023] [Indexed: 06/04/2023]
Abstract
As resident macrophages of the CNS, microglia are critical immune effectors of inflammatory lesions and associated neural dysfunctions. In multiple sclerosis (MS) and its animal models, chronic microglial inflammatory activity damages myelin and disrupts axonal and synaptic activity. In contrast to these detrimental effects, the potent phagocytic and tissue-remodelling capabilities of microglia support critical endogenous repair mechanisms. Although these opposing capabilities have long been appreciated, a precise understanding of their underlying molecular effectors is only beginning to emerge. Here, we review recent advances in our understanding of the roles of microglia in animal models of MS and demyelinating lesions and the mechanisms that underlie their damaging and repairing activities. We also discuss how the structured organization and regulation of the genome enables complex transcriptional heterogeneity within the microglial cell population at demyelinating lesions.
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Affiliation(s)
- Félix Distéfano-Gagné
- Axe Neuroscience, Centre de Recherche du CHU de Québec - Université Laval, Québec, Québec, Canada
- Département de Médecine Moléculaire de la Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Sara Bitarafan
- Axe Neuroscience, Centre de Recherche du CHU de Québec - Université Laval, Québec, Québec, Canada
- Département de Médecine Moléculaire de la Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Steve Lacroix
- Axe Neuroscience, Centre de Recherche du CHU de Québec - Université Laval, Québec, Québec, Canada
- Département de Médecine Moléculaire de la Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - David Gosselin
- Axe Neuroscience, Centre de Recherche du CHU de Québec - Université Laval, Québec, Québec, Canada.
- Département de Médecine Moléculaire de la Faculté de Médecine, Université Laval, Québec, Québec, Canada.
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10
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Raas Q, Tawbeh A, Tahri-Joutey M, Gondcaille C, Keime C, Kaiser R, Trompier D, Nasser B, Leoni V, Bellanger E, Boussand M, Hamon Y, Benani A, Di Cara F, Truntzer C, Cherkaoui-Malki M, Andreoletti P, Savary S. Peroxisomal defects in microglial cells induce a disease-associated microglial signature. Front Mol Neurosci 2023; 16:1170313. [PMID: 37138705 PMCID: PMC10149961 DOI: 10.3389/fnmol.2023.1170313] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 03/27/2023] [Indexed: 05/05/2023] Open
Abstract
Microglial cells ensure essential roles in brain homeostasis. In pathological condition, microglia adopt a common signature, called disease-associated microglial (DAM) signature, characterized by the loss of homeostatic genes and the induction of disease-associated genes. In X-linked adrenoleukodystrophy (X-ALD), the most common peroxisomal disease, microglial defect has been shown to precede myelin degradation and may actively contribute to the neurodegenerative process. We previously established BV-2 microglial cell models bearing mutations in peroxisomal genes that recapitulate some of the hallmarks of the peroxisomal β-oxidation defects such as very long-chain fatty acid (VLCFA) accumulation. In these cell lines, we used RNA-sequencing and identified large-scale reprogramming for genes involved in lipid metabolism, immune response, cell signaling, lysosome and autophagy, as well as a DAM-like signature. We highlighted cholesterol accumulation in plasma membranes and observed autophagy patterns in the cell mutants. We confirmed the upregulation or downregulation at the protein level for a few selected genes that mostly corroborated our observations and clearly demonstrated increased expression and secretion of DAM proteins in the BV-2 mutant cells. In conclusion, the peroxisomal defects in microglial cells not only impact on VLCFA metabolism but also force microglial cells to adopt a pathological phenotype likely representing a key contributor to the pathogenesis of peroxisomal disorders.
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Affiliation(s)
- Quentin Raas
- Laboratoire Bio-PeroxIL EA7270, University of Bourgogne, Dijon, France
| | - Ali Tawbeh
- Laboratoire Bio-PeroxIL EA7270, University of Bourgogne, Dijon, France
| | - Mounia Tahri-Joutey
- Laboratoire Bio-PeroxIL EA7270, University of Bourgogne, Dijon, France
- Laboratory of Biochemistry, Neurosciences, Natural Resources and Environment, Faculty of Sciences and Techniques, University Hassan I, Settat, Morocco
| | | | - Céline Keime
- Plateforme GenomEast, IGBMC, CNRS UMR 7104, Inserm U1258, University of Strasbourg, Illkirch, France
| | - Romain Kaiser
- Plateforme GenomEast, IGBMC, CNRS UMR 7104, Inserm U1258, University of Strasbourg, Illkirch, France
| | - Doriane Trompier
- Laboratoire Bio-PeroxIL EA7270, University of Bourgogne, Dijon, France
| | - Boubker Nasser
- Laboratory of Biochemistry, Neurosciences, Natural Resources and Environment, Faculty of Sciences and Techniques, University Hassan I, Settat, Morocco
| | - Valerio Leoni
- Laboratory of Clinical Biochemistry, Hospital of Desio, ASST-Brianza and Department of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Emma Bellanger
- Aix Marseille Univ, CNRS, INSERM, CIML, Marseille, France
| | - Maud Boussand
- Aix Marseille Univ, CNRS, INSERM, CIML, Marseille, France
| | - Yannick Hamon
- Aix Marseille Univ, CNRS, INSERM, CIML, Marseille, France
| | - Alexandre Benani
- Centre des Sciences du Goût et de l’Alimentation, CNRS, INRAE, Institut Agro Dijon, University of Bourgogne Franche-Comté, Dijon, France
| | - Francesca Di Cara
- Department of Microbiology and Immunology, IWK Health Centre, Dalhousie University, Halifax, NS, Canada
| | - Caroline Truntzer
- Platform of Transfer in Biological Oncology, Georges François Leclerc Cancer Center–Unicancer, Dijon, France
| | | | | | - Stéphane Savary
- Laboratoire Bio-PeroxIL EA7270, University of Bourgogne, Dijon, France
- *Correspondence: Stéphane Savary,
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11
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Vanherle S, Jorissen W, Dierckx T, Loix M, Grajchen E, Mingneau F, Guns J, Gervois P, Lambrichts I, Dehairs J, Swinnen JV, Mulder MT, Remaley AT, Haidar M, Hendriks JJ, Bogie JJ. The ApoA-I mimetic peptide 5A enhances remyelination by promoting clearance and degradation of myelin debris. Cell Rep 2022; 41:111591. [DOI: 10.1016/j.celrep.2022.111591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 09/09/2022] [Accepted: 10/11/2022] [Indexed: 11/09/2022] Open
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12
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Haidar M, Loix M, Vanherle S, Dierckx T, Vangansewinkel T, Gervois P, Wolfs E, Lambrichts I, Bogie JFJ, Hendriks JJA. Targeting lipophagy in macrophages improves repair in multiple sclerosis. Autophagy 2022; 18:2697-2710. [PMID: 35282773 PMCID: PMC9629102 DOI: 10.1080/15548627.2022.2047343] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Foamy macrophages containing abundant intracellular myelin remnants are an important pathological hallmark of multiple sclerosis. Reducing the intracellular lipid burden in foamy macrophages is considered a promising therapeutic strategy to induce a phagocyte phenotype that promotes central nervous system repair. Recent research from our group showed that sustained intracellular accumulation of myelin-derived lipids skews these phagocytes toward a disease-promoting and more inflammatory phenotype. Our data now demonstrate that disturbed lipophagy, a selective form of autophagy that helps with the degradation of lipid droplets, contributes to the induction of this phenotype. Stimulating autophagy using the natural disaccharide trehalose reduced the lipid load and inflammatory phenotype of myelin-laden macrophages. Importantly, trehalose was able to boost remyelination in the ex vivo brain slice model and the in vivo cuprizone-induced demyelination model. In summary, our results provide a molecular rationale for impaired metabolism of myelin-derived lipids in macrophages, and identify lipophagy induction as a promising treatment strategy to promote remyelination.Abbreviations: Baf: bafilomycin a1; BMDM: bone marrow-derived macrophage; CD68: CD68 antigen; CNS: central nervous system; LD: lipid droplet; LIPE/HSL: lipase, hormone sensitive; LPS: lipopolysaccharide; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MBP: myelin basic protein; MGLL: monoglyceride lipase; MS: multiple sclerosis; NO: nitric oxide; NOS2/iNOS: nitric oxide synthase 2, inducible; ORO: oil red o; PNPLA2: patatin-like phospholipase domain containing 2; PLIN2: perilipin 2; TEM: transmission electron microscopy; TFEB: transcription factor EB; TOH: trehalose.
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Affiliation(s)
- Mansour Haidar
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Melanie Loix
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Sam Vanherle
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Tess Dierckx
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Tim Vangansewinkel
- Department of Cardio and Organs Systems, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Pascal Gervois
- Department of Cardio and Organs Systems, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Esther Wolfs
- Department of Cardio and Organs Systems, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Ivo Lambrichts
- Department of Cardio and Organs Systems, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Jeroen F J Bogie
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Jerome J A Hendriks
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
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13
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Loix M, Wouters E, Vanherle S, Dehairs J, McManaman JL, Kemps H, Swinnen JV, Haidar M, Bogie JFJ, Hendriks JJA. Perilipin-2 limits remyelination by preventing lipid droplet degradation. Cell Mol Life Sci 2022; 79:515. [PMID: 36100764 DOI: 10.1007/s00018-022-04547-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 09/01/2022] [Accepted: 09/01/2022] [Indexed: 12/09/2022]
Abstract
Foamy macrophages and microglia containing lipid droplets (LDs) are a pathological hallmark of demyelinating disorders affecting the central nervous system (CNS). We and others showed that excessive accumulation of intracellular lipids drives these phagocytes towards a more inflammatory phenotype, thereby limiting CNS repair. To date, however, the mechanisms underlying LD biogenesis and breakdown in lipid-engorged phagocytes in the CNS, as well as their impact on foamy phagocyte biology and lesion progression, remain poorly understood. Here, we provide evidence that LD-associated protein perilipin-2 (PLIN2) controls LD metabolism in myelin-containing phagocytes. We show that PLIN2 protects LDs from lipolysis-mediated degradation, thereby impairing intracellular processing of myelin-derived lipids in phagocytes. Accordingly, loss of Plin2 stimulates LD turnover in foamy phagocytes, driving them towards a less inflammatory phenotype. Importantly, Plin2-deficiency markedly improves remyelination in the ex vivo brain slice model and in the in vivo cuprizone-induced demyelination model. In summary, we identify PLIN2 as a novel therapeutic target to prevent the pathogenic accumulation of LDs in foamy phagocytes and to stimulate remyelination.
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Affiliation(s)
- Melanie Loix
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
- University MS Center Hasselt, Pelt, Belgium
| | - Elien Wouters
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
- University MS Center Hasselt, Pelt, Belgium
| | - Sam Vanherle
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
- University MS Center Hasselt, Pelt, Belgium
| | - Jonas Dehairs
- Department of Oncology, Laboratory of Lipid Metabolism and Cancer, LKI-Louvain Cancer Institute, KU Leuven-University of Leuven, Leuven, Belgium
| | - James L McManaman
- Department of Obstetrics and Gynaecology, School of Medicine, University of Colorado, Denver, USA
| | - Hannelore Kemps
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
- University MS Center Hasselt, Pelt, Belgium
| | - Johannes V Swinnen
- Department of Oncology, Laboratory of Lipid Metabolism and Cancer, LKI-Louvain Cancer Institute, KU Leuven-University of Leuven, Leuven, Belgium
| | - Mansour Haidar
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
- University MS Center Hasselt, Pelt, Belgium
| | - Jeroen F J Bogie
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
- University MS Center Hasselt, Pelt, Belgium
| | - Jerome J A Hendriks
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium.
- University MS Center Hasselt, Pelt, Belgium.
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14
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Myelin and non-myelin debris contribute to foamy macrophage formation after spinal cord injury. Neurobiol Dis 2022; 163:105608. [PMID: 34979258 PMCID: PMC8783370 DOI: 10.1016/j.nbd.2021.105608] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 12/24/2021] [Accepted: 12/30/2021] [Indexed: 02/03/2023] Open
Abstract
Tissue damage after spinal cord injury (SCI) elicits a robust inflammatory cascade that fails to resolve in a timely manner, resulting in impaired wound healing and cellular regeneration. This inflammatory response is partly mediated by infiltrating immune cells, including macrophages. As professional phagocytes, macrophages initially play an important role in debris clearance at the injury site, which would be necessary for proper tissue regeneration. After SCI, most macrophages become filled with lipid droplets due to excessive uptake of lipid debris, assuming a "foamy" phenotype that is associated with a proinflammatory state. Myelin has been assumed to be the main source of lipid that induces foamy macrophage formation after injury given its abundance in the spinal cord. This assumption has led to the widespread use of purified myelin treatment to model foamy macrophage formation in vitro. However, the assumption that myelin is necessary for foamy macrophage formation remains untested. To this end, we developed a novel foamy macrophage assay utilizing total spinal cord homogenate to include all sources of lipid present at the injury site. Using the myelin basic protein knockout (MBP KO, i.e., Shiverer) mice that lack myelin, we investigated lipid accumulation in foamy macrophages. Primary macrophages treated with myelin-deficient spinal cord homogenate still formed large lipid droplets typically observed in foamy macrophages, although to a lesser degree than cells treated with normal homogenate. Similarly, MBP KO mice subjected to contusive spinal cord injury also formed foamy macrophages that exhibited reduced lipid content and associated with improved histological outcomes and reduced immune cell infiltration. Therefore, the absence of myelin does not preclude foamy macrophage formation, indicating that myelin is not the only major source of lipid that contributes this pathology, even though myelin may alter certain aspects of its inflammatory profile.
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15
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Schnackenberg LK, Thorn DA, Barnette D, Jones EE. MALDI imaging mass spectrometry: an emerging tool in neurology. Metab Brain Dis 2022; 37:105-121. [PMID: 34347208 DOI: 10.1007/s11011-021-00797-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 07/11/2021] [Indexed: 12/24/2022]
Abstract
Neurological disease and disorders remain a large public health threat. Thus, research to improve early detection and/or develop more effective treatment approaches are necessary. Although there are many common techniques and imaging modalities utilized to study these diseases, existing approaches often require a label which can be costly and time consuming. Matrix-assisted laser desorption ionization (MALDI) imaging mass spectrometry (IMS) is a label-free, innovative and emerging technique that produces 2D ion density maps representing the distribution of an analyte(s) across a tissue section in relation to tissue histopathology. One main advantage of MALDI IMS over other imaging modalities is its ability to determine the spatial distribution of hundreds of analytes within a single imaging run, without the need for a label or any a priori knowledge. Within the field of neurology and disease there have been several impactful studies in which MALDI IMS has been utilized to better understand the cellular pathology of the disease and or severity. Furthermore, MALDI IMS has made it possible to map specific classes of analytes to regions of the brain that otherwise may have been lost using more traditional methods. This review will highlight key studies that demonstrate the potential of this technology to elucidate previously unknown phenomenon in neurological disease.
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Affiliation(s)
- Laura K Schnackenberg
- Division of Systems Biology, National Center for Toxicological Research/FDA, 3900 NCTR Rd, Jefferson, AR, USA
| | - David A Thorn
- Division of Systems Biology, National Center for Toxicological Research/FDA, 3900 NCTR Rd, Jefferson, AR, USA
| | - Dustyn Barnette
- Division of Systems Biology, National Center for Toxicological Research/FDA, 3900 NCTR Rd, Jefferson, AR, USA
| | - E Ellen Jones
- Division of Systems Biology, National Center for Toxicological Research/FDA, 3900 NCTR Rd, Jefferson, AR, USA.
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16
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Standiford MM, Grund EM, Howe CL. Citrullinated myelin induces microglial TNFα and inhibits endogenous repair in the cuprizone model of demyelination. J Neuroinflammation 2021; 18:305. [PMID: 34961522 PMCID: PMC8711191 DOI: 10.1186/s12974-021-02360-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 12/15/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Microglia are the primary phagocytes of the central nervous system and are responsible for removing damaged myelin following demyelination. Previous investigations exploring the consequences of myelin phagocytosis on microglial activation overlooked the biochemical modifications present on myelin debris. Such modifications, including citrullination, are increased within the inflammatory environment of multiple sclerosis lesions. METHODS Mouse cortical myelin isolated by ultracentrifugation was citrullinated ex vivo by incubation with the calcium-dependent peptidyl arginine deiminase PAD2. Demyelination was induced by 6 weeks of cuprizone (0.3%) treatment and spontaneous repair was initiated by reversion to normal chow. Citrullinated or unmodified myelin was injected into the primary motor cortex above the cingulum bundle at the time of reversion to normal chow and the consequent impact on remyelination was assessed by measuring the surface area of myelin basic protein-positive fibers in the cortex 3 weeks later. Microglial responses to myelin were characterized by measuring cytokine release, assessing flow cytometric markers of microglial activation, and RNAseq profiling of transcriptional changes. RESULTS Citrullinated myelin induced a unique microglial response marked by increased tumor necrosis factor α (TNFα) production both in vitro and in vivo. This response was not induced by unmodified myelin. Injection of citrullinated myelin but not unmodified myelin into the cortex of cuprizone-demyelinated mice significantly inhibited spontaneous remyelination. Antibody-mediated neutralization of TNFα blocked this effect and restored remyelination to normal levels. CONCLUSIONS These findings highlight the role of post-translation modifications such as citrullination in the determination of microglial activation in response to myelin during demyelination. The inhibition of endogenous repair induced by citrullinated myelin and the reversal of this effect by neutralization of TNFα may have implications for therapeutic approaches to patients with inflammatory demyelinating disorders.
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Affiliation(s)
- Miranda M Standiford
- Neuroscience PhD Program, Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, 55905, USA.,Translational Neuroimmunology Lab, Mayo Clinic, Rochester, MN, 55905, USA.,Multiple Sclerosis and Neurorepair Research Unit, Biogen, Cambridge, MA, 02142, USA
| | - Ethan M Grund
- Neuroscience PhD Program, Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, 55905, USA.,Translational Neuroimmunology Lab, Mayo Clinic, Rochester, MN, 55905, USA
| | - Charles L Howe
- Translational Neuroimmunology Lab, Mayo Clinic, Rochester, MN, 55905, USA. .,Division of Experimental Neurology, Department of Neurology, Mayo Clinic, Rochester, MN, 55905, USA. .,Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, MN, 55905, USA.
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17
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Rahiman N, Zamani P, Badiee A, Arabi L, Alavizadeh SH, Jaafari MR. An insight into the role of liposomal therapeutics in the reversion of Multiple Sclerosis. Expert Opin Drug Deliv 2021; 18:1795-1813. [PMID: 34747298 DOI: 10.1080/17425247.2021.2003327] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Multiple Sclerosis (MS), as an autoimmune disease, has complicated immunopathology, which makes its management relevant to various factors. Novel pharmaceutical vehicles, especially liposomes, can support efficacious handling of this disease both in early detection and prognosis and also in a therapeutic manner. The most well-known trigger of MS onset is the predominance of cellular to humoral immunity and enhancement of inflammatory cytokines level. The installation of liposomes as nanoparticles to control this disease holds great promise up to now. AREAS COVERED Various types of liposomes with different properties and purposes have been formulated and targeted immune cells with their surface manipulations. They may be encapsulated with anti-inflammatory, MS-related therapeutics, or immunodominant myelin-specific peptides for attaining a higher therapeutic efficacy of the drugs or tolerance induction. Cationic liposomes are also highly applicable for gene delivery of the anti-inflammatory cytokines or silencing the inflammatory cytokines. Liposomes have also been used as biotools for comprehending MS pathomechanisms or as diagnostic agents. EXPERT OPINION The efforts to manage MS through nanomedicine, especially liposomal therapeutics, pave a new avenue to a high-throughput medication of this autoimmune disease and their translation to the clinic in the future for overcoming the challenges that MS patients confront.
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Affiliation(s)
- Niloufar Rahiman
- Nanotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Pharmaceutical Nanotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Parvin Zamani
- Department of Pharmaceutical Nanotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Ali Badiee
- Nanotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Pharmaceutical Nanotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Leila Arabi
- Nanotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Pharmaceutical Nanotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Seyedeh Hoda Alavizadeh
- Nanotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Pharmaceutical Nanotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mahmoud Reza Jaafari
- Nanotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Pharmaceutical Nanotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.,Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
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18
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Comparative Review of Microglia and Monocytes in CNS Phagocytosis. Cells 2021; 10:cells10102555. [PMID: 34685535 PMCID: PMC8534258 DOI: 10.3390/cells10102555] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/22/2021] [Accepted: 09/24/2021] [Indexed: 01/08/2023] Open
Abstract
Macrophages maintain tissue homeostasis by phagocytosing and removing unwanted materials such as dead cells and cell debris. Microglia, the resident macrophages of the central nervous system (CNS), are no exception. In addition, a series of recent studies have shown that microglia phagocytose the neuronal synapses that form the basis of neural circuit function. This discovery has spurred many neuroscientists to study microglia. Importantly, in the CNS parenchyma, not only microglia but also blood-derived monocytes, which essentially differentiate into macrophages after infiltration, exert phagocytic ability, making the study of phagocytosis in the CNS even more interesting and complex. In particular, in the diseased brain, the phagocytosis of tissue-damaging substances, such as myelin debris in multiple sclerosis (MS), has been shown to be carried out by both microglia and blood-derived monocytes. However, it remains largely unclear why blood-derived monocytes need to invade the parenchyma, where microglia are already abundant, to assist in phagocytosis. We will also discuss whether this phagocytosis can affect the fate of the phagocytosing cell itself as well as the substance being phagocytosed and the surrounding environment in addition to future research directions. In this review, we will introduce recent studies to answer a question that often arises when studying microglial phagocytosis: under what circumstances and to what extent blood-derived monocytes infiltrate the CNS and contribute to phagocytosis. In addition, the readers will learn how recent studies have experimentally distinguished between microglia and infiltrating monocytes. Finally, we aim to contribute to the progress of phagocytosis research by discussing the effects of phagocytosis on phagocytic cells.
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19
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Microglial 'fat shaming' in development and disease. Curr Opin Cell Biol 2021; 73:105-109. [PMID: 34455405 DOI: 10.1016/j.ceb.2021.07.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 07/19/2021] [Indexed: 12/24/2022]
Abstract
Neuronal-immune interactions are known to play crucial roles in brain development and homoeostasis. Of great relevance in this context are microglia, brain macrophages that phagocytose neurons that die during development, and many neurological disorders. Single-cell RNA sequencing methods have significantly advanced our understanding of microglial heterogeneity and transcriptional response to environmental changes. Here, we review recent work showing how microglia adopt a similar molecular signature during development and disease characterised by the expression of genes linked to phagocytosis and lipid uptake and metabolism. These studies show that in many neurodegenerative conditions, microglia accumulate cholesterols and lipid-rich debris, pointing to lipid processing and transport as promising targets for developing new therapeutical treatments against neurodegenerative disorders.
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20
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Abstract
Tyro3, Axl and Mertk are members of the TAM family of tyrosine kinase receptors. TAMs are activated by two structurally homologous ligands GAS6 and PROS1. TAM receptors and ligands are widely distributed and often co-expressed in the same cells allowing diverse functions across many systems including the immune, reproductive, vascular, and the developing as well as adult nervous systems. This review will focus specifically on TAM signaling in the nervous system, highlighting the essential roles this pathway fulfills in maintaining cell survival and homeostasis, cellular functions such as phagocytosis, immunity and tissue repair. Dysfunctional TAM signaling can cause complications in development, disruptions in homeostasis which can rouse autoimmunity, neuroinflammation and neurodegeneration. The development of therapeutics modulating TAM activities in the nervous system has great prospects, however, foremost we need a complete understanding of TAM signaling pathways.
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Affiliation(s)
- Tal Burstyn-Cohen
- Institute for Dental Sciences, Faculty of Dental Medicine, The Hebrew University-Hadassah, Jerusalem, Israel
| | - Arielle Hochberg
- Institute for Dental Sciences, Faculty of Dental Medicine, The Hebrew University-Hadassah, Jerusalem, Israel
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21
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Van Broeckhoven J, Sommer D, Dooley D, Hendrix S, Franssen AJPM. Macrophage phagocytosis after spinal cord injury: when friends become foes. Brain 2021; 144:2933-2945. [PMID: 34244729 DOI: 10.1093/brain/awab250] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 06/12/2021] [Accepted: 06/20/2021] [Indexed: 11/14/2022] Open
Abstract
After spinal cord injury (SCI), macrophages can exert either beneficial or detrimental effects depending on their phenotype. Aside from their critical role in inflammatory responses, macrophages are also specialized in the recognition, engulfment, and degradation of pathogens, apoptotic cells, and tissue debris. They promote remyelination and axonal regeneration by removing inhibitory myelin components and cellular debris. However, excessive intracellular presence of lipids and dysregulated intracellular lipid homeostasis result in the formation of foamy macrophages. These develop a pro-inflammatory phenotype that may contribute to further neurological decline. Additionally, myelin-activated macrophages play a crucial role in axonal dieback and retraction. Here, we review the opposing functional consequences of phagocytosis by macrophages in SCI, including remyelination and regeneration versus demyelination, degeneration, and axonal dieback. Furthermore, we discuss how targeting the phagocytic ability of macrophages may have therapeutic potential for the treatment of SCI.
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Affiliation(s)
- Jana Van Broeckhoven
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Daniela Sommer
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Dearbhaile Dooley
- School of Medicine, Health Sciences Centre, University College Dublin, Belfield Dublin 4, Ireland.,UCD Conway Institute of Biomolecular & Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
| | - Sven Hendrix
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium.,Medical School Hamburg, Hamburg, Germany
| | - Aimée J P M Franssen
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
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22
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Phloretin suppresses neuroinflammation by autophagy-mediated Nrf2 activation in macrophages. J Neuroinflammation 2021; 18:148. [PMID: 34218792 PMCID: PMC8254976 DOI: 10.1186/s12974-021-02194-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 06/16/2021] [Indexed: 12/31/2022] Open
Abstract
Background Macrophages play a dual role in neuroinflammatory disorders such as multiple sclerosis (MS). They are involved in lesion onset and progression but can also promote the resolution of inflammation and repair of damaged tissue. In this study, we investigate if and how phloretin, a flavonoid abundantly present in apples and strawberries, lowers the inflammatory phenotype of macrophages and suppresses neuroinflammation. Methods Transcriptional changes in mouse bone marrow-derived macrophages upon phloretin exposure were assessed by bulk RNA sequencing. Underlying pathways related to inflammation, oxidative stress response and autophagy were validated by quantitative PCR, fluorescent and absorbance assays, nuclear factor erythroid 2–related factor 2 (Nrf2) knockout mice, western blot, and immunofluorescence. The experimental autoimmune encephalomyelitis (EAE) model was used to study the impact of phloretin on neuroinflammation in vivo and confirm underlying mechanisms. Results We show that phloretin reduces the inflammatory phenotype of macrophages and markedly suppresses neuroinflammation in EAE. Phloretin mediates its effect by activating the Nrf2 signaling pathway. Nrf2 activation was attributed to 5′ AMP-activated protein kinase (AMPK)-dependent activation of autophagy and subsequent kelch-like ECH-associated protein 1 (Keap1) degradation. Conclusions This study opens future perspectives for phloretin as a therapeutic strategy for neuroinflammatory disorders such as MS. Trial registration Not applicable. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-021-02194-z.
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23
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Bogie JFJ, Grajchen E, Wouters E, Corrales AG, Dierckx T, Vanherle S, Mailleux J, Gervois P, Wolfs E, Dehairs J, Van Broeckhoven J, Bowman AP, Lambrichts I, Gustafsson JÅ, Remaley AT, Mulder M, Swinnen JV, Haidar M, Ellis SR, Ntambi JM, Zelcer N, Hendriks JJA. Stearoyl-CoA desaturase-1 impairs the reparative properties of macrophages and microglia in the brain. J Exp Med 2020; 217:133840. [PMID: 32097464 PMCID: PMC7201924 DOI: 10.1084/jem.20191660] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 12/12/2019] [Accepted: 01/24/2020] [Indexed: 12/15/2022] Open
Abstract
Failure of remyelination underlies the progressive nature of demyelinating diseases such as multiple sclerosis. Macrophages and microglia are crucially involved in the formation and repair of demyelinated lesions. Here we show that myelin uptake temporarily skewed these phagocytes toward a disease-resolving phenotype, while sustained intracellular accumulation of myelin induced a lesion-promoting phenotype. This phenotypic shift was controlled by stearoyl-CoA desaturase-1 (SCD1), an enzyme responsible for the desaturation of saturated fatty acids. Monounsaturated fatty acids generated by SCD1 reduced the surface abundance of the cholesterol efflux transporter ABCA1, which in turn promoted lipid accumulation and induced an inflammatory phagocyte phenotype. Pharmacological inhibition or phagocyte-specific deficiency of Scd1 accelerated remyelination ex vivo and in vivo. These findings identify SCD1 as a novel therapeutic target to promote remyelination.
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Affiliation(s)
- Jeroen F J Bogie
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Elien Grajchen
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Elien Wouters
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Aida Garcia Corrales
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Tess Dierckx
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Sam Vanherle
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Jo Mailleux
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Pascal Gervois
- Department of Cardio and Organ Systems, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Esther Wolfs
- Department of Cardio and Organ Systems, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Jonas Dehairs
- Department of Oncology, Laboratory of Lipid Metabolism and Cancer, Leuven Cancer Institute, University of Leuven, Leuven, Belgium
| | - Jana Van Broeckhoven
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Andrew P Bowman
- The Maastricht MultiModal Molecular Imaging Institute, Division of Imaging Mass Spectrometry, Maastricht University, Maastricht, Netherlands
| | - Ivo Lambrichts
- Department of Cardio and Organ Systems, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Jan-Åke Gustafsson
- Center for Nuclear Receptors and Cell Signaling, University of Houston, Houston, TX.,Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Alan T Remaley
- Lipoprotein Metabolism Laboratory, Translational Vascular Medicine Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Monique Mulder
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Johannes V Swinnen
- Department of Oncology, Laboratory of Lipid Metabolism and Cancer, Leuven Cancer Institute, University of Leuven, Leuven, Belgium
| | - Mansour Haidar
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Shane R Ellis
- The Maastricht MultiModal Molecular Imaging Institute, Division of Imaging Mass Spectrometry, Maastricht University, Maastricht, Netherlands
| | - James M Ntambi
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI.,Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI
| | - Noam Zelcer
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Jerome J A Hendriks
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
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24
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Wouters E, Grajchen E, Jorissen W, Dierckx T, Wetzels S, Loix M, Tulleners MP, Staels B, Stinissen P, Haidar M, Bogie JF, Hendriks JJ. Altered PPARγ Expression Promotes Myelin-Induced Foam Cell Formation in Macrophages in Multiple Sclerosis. Int J Mol Sci 2020; 21:ijms21239329. [PMID: 33297574 PMCID: PMC7731422 DOI: 10.3390/ijms21239329] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 12/03/2020] [Indexed: 01/24/2023] Open
Abstract
Macrophages play a crucial role during the pathogenesis of multiple sclerosis (MS), a neuroinflammatory autoimmune disorder of the central nervous system. Important regulators of the metabolic and inflammatory phenotype of macrophages are liver X receptors (LXRs) and peroxisome proliferator-activated receptors (PPARs). Previously, it has been reported that PPARγ expression is decreased in peripheral blood mononuclear cells of MS patients. The goal of the present study was to determine to what extent PPARγ, as well as the closely related nuclear receptors PPARα and β and LXRα and β, are differentially expressed in monocytes from MS patients and how this change in expression affects the function of monocyte-derived macrophages. We demonstrate that monocytes of relapsing-remitting MS patients display a marked decrease in PPARγ expression, while the expression of PPARα and LXRα/β is not altered. Interestingly, exposure of monocyte-derived macrophages from healthy donors to MS-associated proinflammatory cytokines mimicked this reduction in PPARγ expression. While a reduced PPARγ expression did not affect the inflammatory and phagocytic properties of myelin-loaded macrophages, it did impact myelin processing by increasing the intracellular cholesterol load of myelin-phagocytosing macrophages. Collectively, our findings indicate that an inflammation-induced reduction in PPARγ expression promotes myelin-induced foam cell formation in macrophages in MS.
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Affiliation(s)
- Elien Wouters
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium; (E.W.); (E.G.); (W.J.); (T.D.); (M.L.); (M.P.T.); (P.S.); (M.H.); (J.F.J.B.)
| | - Elien Grajchen
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium; (E.W.); (E.G.); (W.J.); (T.D.); (M.L.); (M.P.T.); (P.S.); (M.H.); (J.F.J.B.)
| | - Winde Jorissen
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium; (E.W.); (E.G.); (W.J.); (T.D.); (M.L.); (M.P.T.); (P.S.); (M.H.); (J.F.J.B.)
| | - Tess Dierckx
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium; (E.W.); (E.G.); (W.J.); (T.D.); (M.L.); (M.P.T.); (P.S.); (M.H.); (J.F.J.B.)
| | - Suzan Wetzels
- Department of Pathology, CARIM, Maastricht University Medical Center, 6229 HX Maastricht, The Netherlands;
| | - Melanie Loix
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium; (E.W.); (E.G.); (W.J.); (T.D.); (M.L.); (M.P.T.); (P.S.); (M.H.); (J.F.J.B.)
| | - Marie Paule Tulleners
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium; (E.W.); (E.G.); (W.J.); (T.D.); (M.L.); (M.P.T.); (P.S.); (M.H.); (J.F.J.B.)
| | - Bart Staels
- University of Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1011-EGID, F-59000 Lille, France;
| | - Piet Stinissen
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium; (E.W.); (E.G.); (W.J.); (T.D.); (M.L.); (M.P.T.); (P.S.); (M.H.); (J.F.J.B.)
| | - Mansour Haidar
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium; (E.W.); (E.G.); (W.J.); (T.D.); (M.L.); (M.P.T.); (P.S.); (M.H.); (J.F.J.B.)
| | - Jeroen F.J. Bogie
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium; (E.W.); (E.G.); (W.J.); (T.D.); (M.L.); (M.P.T.); (P.S.); (M.H.); (J.F.J.B.)
| | - Jerome J.A. Hendriks
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium; (E.W.); (E.G.); (W.J.); (T.D.); (M.L.); (M.P.T.); (P.S.); (M.H.); (J.F.J.B.)
- Correspondence:
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25
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Wu S, Romero-Ramírez L, Mey J. Retinoic acid increases phagocytosis of myelin by macrophages. J Cell Physiol 2020; 236:3929-3945. [PMID: 33165955 PMCID: PMC7984038 DOI: 10.1002/jcp.30137] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 10/21/2020] [Accepted: 10/23/2020] [Indexed: 12/28/2022]
Abstract
Traumatic injuries of the central nervous system (CNS) are followed by the accumulation of cellular debris including proteins and lipids from myelinated fiber tracts. Insufficient phagocytic clearance of myelin debris influences the pathological process because it induces inflammation and blocks axonal regeneration. We investigated whether ligands of nuclear receptor families retinoic acid receptors (RARs), retinoid X receptors, peroxisome proliferator-activated receptors, lipid X receptors, and farnesoid X receptors increase myelin phagocytosis by murine bone marrow-derived macrophages and Raw264.7 cells. Using in vitro assays with 3,3'-dioctadecyloxacarbocyanine perchlorate- and pHrodo-labeled myelin we found that the transcriptional activator all-trans retinoic acid (RA)enhanced endocytosis of myelin involving the induction of tissue transglutaminase-2. The RAR-dependent increase of phagocytosis was not associated with changes in gene expression of receptors FcγR1, FcγR2b, FcγR3, TREM2, DAP12, CR3, or MerTK. The combination of RA and myelin exposure significantly reduced the expression of M1 marker genes inducible nitric oxide synthase and interleukin-1β and increased expression of transmembrane proteins CD36 and ABC-A1, which are involved in lipid transport and metabolism. The present results suggest an additional mechanism for therapeutic applications of RA after CNS trauma. It remains to be studied whether endogenous RA-signaling regulates phagocytosis in vivo.
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Affiliation(s)
- Siyu Wu
- Laboratorio Regeneración Neuronal e Inmunidad Innata, Hospital Nacional de Parapléjicos, Toledo, Spain.,School of Mental Health and Neuroscience and EURON Graduate School of Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Lorenzo Romero-Ramírez
- Laboratorio Regeneración Neuronal e Inmunidad Innata, Hospital Nacional de Parapléjicos, Toledo, Spain
| | - Jörg Mey
- Laboratorio Regeneración Neuronal e Inmunidad Innata, Hospital Nacional de Parapléjicos, Toledo, Spain.,School of Mental Health and Neuroscience and EURON Graduate School of Neuroscience, Maastricht University, Maastricht, The Netherlands
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26
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Zierfuss B, Weinhofer I, Buda A, Popitsch N, Hess L, Moos V, Hametner S, Kemp S, Köhler W, Forss‐Petter S, Seiser C, Berger J. Targeting foam cell formation in inflammatory brain diseases by the histone modifier MS-275. Ann Clin Transl Neurol 2020; 7:2161-2177. [PMID: 32997393 PMCID: PMC7664285 DOI: 10.1002/acn3.51200] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 08/25/2020] [Accepted: 08/30/2020] [Indexed: 01/10/2023] Open
Abstract
OBJECTIVE To assess class I-histone deacetylase (HDAC) inhibition on formation of lipid-accumulating, disease-promoting phagocytes upon myelin load in vitro, relevant for neuroinflammatory disorders like multiple sclerosis (MS) and cerebral X-linked adrenoleukodystrophy (X-ALD). METHODS Immunohistochemistry on postmortem brain tissue of acute MS (n = 6) and cerebral ALD (n = 4) cases to analyze activation and foam cell state of phagocytes. RNA-Seq of in vitro differentiated healthy macrophages (n = 8) after sustained myelin-loading to assess the metabolic shift associated with foam cell formation. RNA-Seq analysis of genes linked to lipid degradation and export in MS-275-treated human HAP1 cells and RT-qPCR analysis of HAP1 cells knocked out for individual members of class I HDACs or the corresponding enzymatically inactive knock-in mutants. Investigation of intracellular lipid/myelin content after MS-275 treatment of myelin-laden human foam cells. Analysis of disease characteristic very long-chain fatty acid (VLCFA) metabolism and inflammatory state in MS-275-treated X-ALD macrophages. RESULTS Enlarged foam cells coincided with a pro-inflammatory, lesion-promoting phenotype in postmortem tissue of MS and cerebral ALD patients. Healthy in vitro myelin laden foam cells upregulated genes linked to LXRα/PPARγ pathways and mimicked a program associated with tissue repair. Treating these cells with MS-275, amplified this gene transcription program and significantly reduced lipid and cholesterol accumulation and, thus, foam cell formation. In macrophages derived from X-ALD patients, MS-275 improved the disease-associated alterations of VLCFA metabolism and reduced the pro-inflammatory status of these cells. INTERPRETATION These findings identify class I-HDAC inhibition as a potential novel strategy to prevent disease promoting foam cell formation in CNS inflammation.
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Affiliation(s)
- Bettina Zierfuss
- Department of Pathobiology of the Nervous SystemCentre for Brain ResearchMedical University of ViennaVienna1090Austria
| | - Isabelle Weinhofer
- Department of Pathobiology of the Nervous SystemCentre for Brain ResearchMedical University of ViennaVienna1090Austria
| | - Agnieszka Buda
- Department of Pathobiology of the Nervous SystemCentre for Brain ResearchMedical University of ViennaVienna1090Austria
| | - Niko Popitsch
- Institute of Molecular BiotechnologyVienna1030Austria
| | - Lena Hess
- Division of Cell and Developmental BiologyCenter for Anatomy and Cell BiologyMedical University of ViennaVienna1090Austria
| | - Verena Moos
- Division of Cell and Developmental BiologyCenter for Anatomy and Cell BiologyMedical University of ViennaVienna1090Austria
| | - Simon Hametner
- Department of Neuropathology and NeurochemistryMedical University of ViennaVienna1090Austria
| | - Stephan Kemp
- Laboratory Genetic Metabolic DiseasesAmsterdam UMCAmsterdam Gastroenterology & MetabolismAmsterdam NeuroscienceUniversity of AmsterdamAmsterdam1105AZThe Netherlands
| | - Wolfgang Köhler
- Department of NeurologyUniversity of Leipzig Medical CentreLeukodystrophy ClinicLeipzig04103Germany
| | - Sonja Forss‐Petter
- Department of Pathobiology of the Nervous SystemCentre for Brain ResearchMedical University of ViennaVienna1090Austria
| | - Christian Seiser
- Division of Cell and Developmental BiologyCenter for Anatomy and Cell BiologyMedical University of ViennaVienna1090Austria
| | - Johannes Berger
- Department of Pathobiology of the Nervous SystemCentre for Brain ResearchMedical University of ViennaVienna1090Austria
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27
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Pinto MV, Fernandes A. Microglial Phagocytosis-Rational but Challenging Therapeutic Target in Multiple Sclerosis. Int J Mol Sci 2020; 21:ijms21175960. [PMID: 32825077 PMCID: PMC7504120 DOI: 10.3390/ijms21175960] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 08/12/2020] [Accepted: 08/17/2020] [Indexed: 12/14/2022] Open
Abstract
Multiple sclerosis (MS) is the most common autoimmune and demyelinating disease of the central nervous system (CNS), characterized, in the majority of cases, by initial relapses that later evolve into progressive neurodegeneration, severely impacting patients’ motor and cognitive functions. Despite the availability of immunomodulatory therapies effective to reduce relapse rate and slow disease progression, they all failed to restore CNS myelin that is necessary for MS full recovery. Microglia are the primary inflammatory cells present in MS lesions, therefore strongly contributing to demyelination and lesion extension. Thus, many microglial-based therapeutic strategies have been focused on the suppression of microglial pro-inflammatory phenotype and neurodegenerative state to reduce disease severity. On the other hand, the contribution of myelin phagocytosis advocating the neuroprotective role of microglia in MS has been less explored. Indeed, despite the presence of functional oligodendrocyte precursor cells (OPCs), within lesioned areas, MS plaques fail to remyelinate as a result of the over-accumulation of myelin-toxic debris that must be cleared away by microglia. Dysregulation of this process has been associated with the impaired neuronal recovery and deficient remyelination. In line with this, here we provide a comprehensive review of microglial myelin phagocytosis and its involvement in MS development and repair. Alongside, we discuss the potential of phagocytic-mediated therapeutic approaches and encourage their modulation as a novel and rational approach to ameliorate MS-associated pathology.
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Affiliation(s)
- Maria V. Pinto
- Neuron-Glia Biology in Health and Disease, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal;
| | - Adelaide Fernandes
- Neuron-Glia Biology in Health and Disease, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal;
- Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal
- Correspondence: ; Tel.: +351-217946400
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28
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Chausse B, Kakimoto PA, Kann O. Microglia and lipids: how metabolism controls brain innate immunity. Semin Cell Dev Biol 2020; 112:137-144. [PMID: 32807643 DOI: 10.1016/j.semcdb.2020.08.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/31/2020] [Accepted: 08/01/2020] [Indexed: 12/26/2022]
Abstract
Microglia are universal sensors of alterations in CNS physiology. These cells integrate complex molecular signals and undergo comprehensive phenotypical remodeling to adapt inflammatory responses. In the last years, single-cell analyses have revealed that microglia exhibit diverse phenotypes during development, growth and disease. Emerging evidence suggests that such phenotype transitions are mediated by reprogramming of cell metabolism. Indeed, metabolic pathways are distinctively altered in activated microglia and are central nodes controlling microglial responses. Microglial lipid metabolism has been specifically involved in the control of microglial activation and effector functions, such as migration, phagocytosis and inflammatory signaling, and minor disturbances in microglial lipid handling associates with altered brain function in disorders featuring neuroinflammation. In this review, we explore new and relevant aspects of microglial metabolism in health and disease. We give special focus on how different branches of lipid metabolism, such as lipid sensing, synthesis and oxidation, integrate and control essential aspects of microglial biology, and how disturbances in these processes associate with aging and the pathogenesis of, for instance, multiple sclerosis and Alzheimer's disease. Finally, challenges and advances in microglial lipid research are discussed.
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Affiliation(s)
- Bruno Chausse
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany.
| | - Pamela A Kakimoto
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, 05508-000, São Paulo, Brazil
| | - Oliver Kann
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany; Interdisciplinary Center for Neurosciences, University of Heidelberg, D-69120 Heidelberg, Germany
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29
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Grajchen E, Wouters E, van de Haterd B, Haidar M, Hardonnière K, Dierckx T, Van Broeckhoven J, Erens C, Hendrix S, Kerdine-Römer S, Hendriks JJA, Bogie JFJ. CD36-mediated uptake of myelin debris by macrophages and microglia reduces neuroinflammation. J Neuroinflammation 2020; 17:224. [PMID: 32718316 PMCID: PMC7384221 DOI: 10.1186/s12974-020-01899-x] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 07/15/2020] [Indexed: 11/24/2022] Open
Abstract
Background The presence of foamy macrophages and microglia containing intracellular myelin remnants is a pathological hallmark of neurodegenerative disorders such as multiple sclerosis (MS). Despite the importance of myelin internalization in affecting both central nervous system repair and neuroinflammation, the receptors involved in myelin clearance and their impact on the phagocyte phenotype and lesion progression remain to be clarified. Methods Flow cytometry, quantitative PCR, and immunohistochemistry were used to define the mRNA and protein abundance of CD36 in myelin-containing phagocytes. The impact of CD36 and nuclear factor erythroid 2–related factor 2 (NRF2) on the phagocytic and inflammatory features of macrophages and microglia was assessed using a pharmacological CD36 inhibitor (sulfo-N-succinimidyl oleate) and Nrf2−/− bone marrow-derived macrophages. Finally, the experimental autoimmune encephalomyelitis (EAE) model was used to establish the impact of CD36 inhibition on neuroinflammation and myelin phagocytosis in vivo. Results Here, we show that the fatty acid translocase CD36 is required for the uptake of myelin debris by macrophages and microglia, and that myelin internalization increased CD36 expression through NRF2. Pharmacological inhibition of CD36 promoted the inflammatory properties of myelin-containing macrophages and microglia in vitro, which was paralleled by a reduced activity of the anti-inflammatory lipid-sensing liver X receptors and peroxisome proliferator-activated receptors. By using the EAE model, we provide evidence that CD36 is essential for myelin debris clearance in vivo. Importantly, CD36 inhibition markedly increased the neuroinflammatory burden and disease severity in the EAE model. Conclusion Altogether, we show for the first time that CD36 is crucial for clearing myelin debris and suppressing neuroinflammation in demyelinating disorders such as MS.
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Affiliation(s)
- Elien Grajchen
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Elien Wouters
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Britt van de Haterd
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Mansour Haidar
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Kévin Hardonnière
- Inflammation, Microbiome and Immunosurveillance, INSERM UMR99, Université Paris-Saclay, Châtenay-Malabry, France
| | - Tess Dierckx
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Jana Van Broeckhoven
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Celine Erens
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Sven Hendrix
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Saadia Kerdine-Römer
- Inflammation, Microbiome and Immunosurveillance, INSERM UMR99, Université Paris-Saclay, Châtenay-Malabry, France
| | - Jerome J A Hendriks
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Jeroen F J Bogie
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium.
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30
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Wagner N, Wagner KD. PPAR Beta/Delta and the Hallmarks of Cancer. Cells 2020; 9:cells9051133. [PMID: 32375405 PMCID: PMC7291220 DOI: 10.3390/cells9051133] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 04/30/2020] [Accepted: 05/01/2020] [Indexed: 12/17/2022] Open
Abstract
Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear hormone receptor family. Three different isoforms, PPAR alpha, PPAR beta/delta and PPAR gamma have been identified. They all form heterodimers with retinoic X receptors to activate or repress downstream target genes dependent on the presence/absence of ligands and coactivators or corepressors. PPARs differ in their tissue expression profile, ligands and specific agonists and antagonists. PPARs attract attention as potential therapeutic targets for a variety of diseases. PPAR alpha and gamma agonists are in clinical use for the treatment of dyslipidemias and diabetes. For both receptors, several clinical trials as potential therapeutic targets for cancer are ongoing. In contrast, PPAR beta/delta has been suggested as a therapeutic target for metabolic syndrome. However, potential risks in the settings of cancer are less clear. A variety of studies have investigated PPAR beta/delta expression or activation/inhibition in different cancer cell models in vitro, but the relevance for cancer growth in vivo is less well documented and controversial. In this review, we summarize critically the knowledge of PPAR beta/delta functions for the different hallmarks of cancer biological capabilities, which interplay to determine cancer growth.
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31
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Fitzpatrick JM, Minogue E, Curham L, Tyrrell H, Gavigan P, Hind W, Downer EJ. MyD88-dependent and -independent signalling via TLR3 and TLR4 are differentially modulated by Δ 9-tetrahydrocannabinol and cannabidiol in human macrophages. J Neuroimmunol 2020; 343:577217. [PMID: 32244040 DOI: 10.1016/j.jneuroim.2020.577217] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 03/12/2020] [Accepted: 03/18/2020] [Indexed: 12/17/2022]
Abstract
Toll-like receptors (TLRs) are sensors of pathogen-associated molecules that trigger inflammatory signalling in innate immune cells including macrophages. All TLRs, with the exception of TLR3, promote intracellular signalling via recruitment of the myeloid differentiation factor 88 (MyD88) adaptor, while TLR3 signals via Toll-Interleukin-1 Receptor (TIR)-domain-containing adaptor-inducing interferon (IFN)-β (TRIF) adaptor to induce MyD88-independent signalling. Furthermore, TLR4 can activate both MyD88-dependent and -independent signalling (via TRIF). The study aim was to decipher the impact of the highly purified plant-derived (phyto) cannabinoids Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), when delivered in isolation and in combination (1:1), on MyD88-dependent and -independent signalling in macrophages. We employed the use of the viral dsRNA mimetic poly(I:C) and endotoxin lipopolysaccharide (LPS), to induce viral TLR3 and bacterial TLR4 signalling in human Tamm-Horsfall protein-1 (THP-1)-derived macrophages, respectively. TLR3/TLR4 stimulation promoted the activation of interferon (IFN) regulatory factor 3 (IRF3) and TLR4 promoted the activation of nuclear factor (NF)-κB signalling, with downstream production of the type I IFN-β, the chemokines CXCL10 and CXCL8, and cytokine TNF-α. THC and CBD (both at 10 μM) attenuated TLR3/4-induced IRF3 activation and induction of CXCL10/IFN-β, while both phytocannabinoids failed to impact TLR4-induced IκB-α degradation and TNF-α/CXCL8 expression. The role of CB1, CB2 and PPARγ receptors in mediating the effect of THC and CBD on MyD88-independent signalling was investigated. TLRs are attractive therapeutic targets given their role in inflammation and initiation of adaptive immunity, and data herein indicate that both CBD and THC preferentially modulate TLR3 and TLR4 signalling via MyD88-independent mechanisms in macrophages. This offers mechanistic insight into the role of phytocannabinoids in modulating cellular inflammation.
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Affiliation(s)
- John-Mark Fitzpatrick
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - Eleanor Minogue
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - Lucy Curham
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - Harry Tyrrell
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - Philip Gavigan
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - William Hind
- GW Research Ltd, Sovereign House, Vision Park, Histon, CB24 9BZ, United Kingdom
| | - Eric J Downer
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland.
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Biliktu M, Senol SP, Temiz-Resitoglu M, Guden DS, Horat MF, Sahan-Firat S, Sevim S, Tunctan B. Pharmacological inhibition of soluble epoxide hydrolase attenuates chronic experimental autoimmune encephalomyelitis by modulating inflammatory and anti-inflammatory pathways in an inflammasome-dependent and -independent manner. Inflammopharmacology 2020; 28:1509-1524. [PMID: 32128702 DOI: 10.1007/s10787-020-00691-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Accepted: 02/06/2020] [Indexed: 12/15/2022]
Abstract
We aimed to determine the effect of soluble epoxide hydrolase (sEH) inhibition on chronic experimental autoimmune encephalomyelitis (EAE), a murine model of multiple sclerosis (MS), associated with changes in inflammasome-dependent and -independent inflammatory and anti-inflammatory pathways in the CNS of mice. C57BL/6 mice were used to induce chronic EAE by using an injection of MOG35-55 peptide/PT. Animals were observed daily and scored for EAE signs for 25 days after immunization. Following the induction of EAE, the scores were increased after 9 days and reached peak value as determined by ≥ 2 or ≤ 3 with 8% mortality rate on day 17. On day 17, mice were administered daily PBS, DMSO, or TPPU (a potent sEH inhibitor) (1, 3, or 10 mg/kg) until the end of the study. TPPU only at 3 mg/kg dose decreased the AUC values calculated from EAE scores obtained during the disease compared to EAE and vehicle control groups. On day 25, TPPU also caused an increase in the PPARα/β/γ and NLRC3 proteins and a decrease in the proteins of TLR4, MyD88, NF-κB p65, p-NF-κB p65, iNOS/nNOS, COX-2, NLRC4, ASC, caspase-1 p20, IL-1β, caspase-11 p20, NOX subunits (gp91phox and p47phox), and nitrotyrosine in addition to 14,15-DHET and IL-1β levels compared to EAE and vehicle control groups. Our findings suggest that pharmacological inhibition of sEH attenuates chronic EAE likely because of enhanced levels of anti-inflammatory EETs in addition to PPARα/β/γ and NLRC3 expression associated with suppressed inflammatory TLR4/MyD88/NF-κB signalling pathway, NLRC4/ASC/pro-caspase-1 inflammasome, caspase-11 inflammasome, and NOX activity that are responsible for inflammatory mediator formation in the CNS of mice.
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Affiliation(s)
- Merve Biliktu
- Department of Pharmacology, Faculty of Pharmacy, Yenisehir Campus, Mersin University, 33160, Yenisehir, Mersin, Turkey
| | - Sefika Pinar Senol
- Department of Pharmacology, Faculty of Pharmacy, Yenisehir Campus, Mersin University, 33160, Yenisehir, Mersin, Turkey
| | - Meryem Temiz-Resitoglu
- Department of Pharmacology, Faculty of Pharmacy, Yenisehir Campus, Mersin University, 33160, Yenisehir, Mersin, Turkey
| | - Demet Sinem Guden
- Department of Pharmacology, Faculty of Pharmacy, Yenisehir Campus, Mersin University, 33160, Yenisehir, Mersin, Turkey
| | - Mehmet Furkan Horat
- Department of Pharmacology, Faculty of Pharmacy, Yenisehir Campus, Mersin University, 33160, Yenisehir, Mersin, Turkey
| | - Seyhan Sahan-Firat
- Department of Pharmacology, Faculty of Pharmacy, Yenisehir Campus, Mersin University, 33160, Yenisehir, Mersin, Turkey
| | - Serhan Sevim
- Department of Neurology, Faculty of Medicine, Mersin University, Mersin, Turkey
| | - Bahar Tunctan
- Department of Pharmacology, Faculty of Pharmacy, Yenisehir Campus, Mersin University, 33160, Yenisehir, Mersin, Turkey.
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Bowman AP, Bogie JFJ, Hendriks JJA, Haidar M, Belov M, Heeren RMA, Ellis SR. Evaluation of lipid coverage and high spatial resolution MALDI-imaging capabilities of oversampling combined with laser post-ionisation. Anal Bioanal Chem 2019; 412:2277-2289. [PMID: 31879798 PMCID: PMC7118047 DOI: 10.1007/s00216-019-02290-3] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 11/04/2019] [Accepted: 11/18/2019] [Indexed: 01/28/2023]
Abstract
Matrix-assisted laser desorption/ionisation-mass spectrometry imaging (MALDI-MSI) is a powerful technique for visualising the spatial locations of lipids in biological tissues. However, a major challenge in interpreting the biological significance of local lipid compositions and distributions detected using MALDI-MSI is the difficulty in associating spectra with cellular lipid metabolism within the tissue. By-and-large this is due to the typically limited spatial resolution of MALDI-MSI (30–100 μm) meaning individual spectra represent the average spectrum acquired from multiple adjacent cells, each potentially possessing a unique lipid composition and biological function. The use of oversampling is one promising approach to decrease the sampling area and improve the spatial resolution in MALDI-MSI, but it can suffer from a dramatically decreased sensitivity. In this work we overcome these challenges through the coupling of oversampling MALDI-MSI with laser post-ionisation (MALDI-2). We demonstrate the ability to acquire rich lipid spectra from pixels as small as 6 μm, equivalent to or smaller than the size of typical mammalian cells. Coupled with an approach for automated lipid identification, it is shown that MALDI-2 combined with oversampling at 6 μm pixel size can detect up to three times more lipids and many more lipid classes than even conventional MALDI at 20 μm resolution in the positive-ion mode. Applying this to mouse kidney and human brain tissue containing active multiple sclerosis lesions, where 74 and 147 unique lipids are identified, respectively, the localisation of lipid signals to individual tubuli within the kidney and lipid droplets with lesion-specific macrophages is demonstrated. Graphical abstract ![]()
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Affiliation(s)
- Andrew P Bowman
- Maastricht MultiModal Molecular Imaging (M4I) Institute, Division of Imaging Mass Spectrometry, Maastricht University, Universiteitssingel 50, 6629, ER, Maastricht, The Netherlands
| | - Jeroen F J Bogie
- Department of Immunology and Biochemistry, Biomedical Research Institute, Hasselt University, 3590, Diepenbeek, Belgium
| | - Jerome J A Hendriks
- Department of Immunology and Biochemistry, Biomedical Research Institute, Hasselt University, 3590, Diepenbeek, Belgium
| | - Mansour Haidar
- Department of Immunology and Biochemistry, Biomedical Research Institute, Hasselt University, 3590, Diepenbeek, Belgium
| | | | - Ron M A Heeren
- Maastricht MultiModal Molecular Imaging (M4I) Institute, Division of Imaging Mass Spectrometry, Maastricht University, Universiteitssingel 50, 6629, ER, Maastricht, The Netherlands
| | - Shane R Ellis
- Maastricht MultiModal Molecular Imaging (M4I) Institute, Division of Imaging Mass Spectrometry, Maastricht University, Universiteitssingel 50, 6629, ER, Maastricht, The Netherlands.
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Ruiz F, Vigne S, Pot C. Resolution of inflammation during multiple sclerosis. Semin Immunopathol 2019; 41:711-726. [PMID: 31732775 PMCID: PMC6881249 DOI: 10.1007/s00281-019-00765-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 09/27/2019] [Indexed: 12/14/2022]
Abstract
Multiple sclerosis (MS) is a frequent autoimmune demyelinating disease of the central nervous system (CNS). There are three clinical forms described: relapsing-remitting multiple sclerosis (RRMS), the most common initial presentation (85%) among which, if not treated, about half will transform, into the secondary progressive multiple sclerosis (SPMS) and the primary progressive MS (PPMS) (15%) that is directly progressive without superimposed clinical relapses. Inflammation is present in all subsets of MS. The relapsing/remitting form could represent itself a particular interest for the study of inflammation resolution even though it remains incomplete in MS. Successful resolution of acute inflammation is a highly regulated process and dependent on mechanisms engaged early in the inflammatory response that are scarcely studied in MS. Moreover, recent classes of disease-modifying treatment (DMTs) that are effective against RRMS act by re-establishing the inflammatory imbalance, taking advantage of the pre-existing endogenous suppressor. In this review, we will discuss the active role of regulatory immune cells in inflammation resolution as well as the role of tissue and non-hematopoietic cells as contributors to inflammation resolution. Finally, we will explore how DMTs, more specifically induction therapies, impact the resolution of inflammation during MS.
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Affiliation(s)
- F Ruiz
- Laboratories of Neuroimmunology, Neuroscience Research Center and Service of Neurology, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Chemin des Boveresses 155, 1066, Epalinges, Switzerland
| | - S Vigne
- Laboratories of Neuroimmunology, Neuroscience Research Center and Service of Neurology, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Chemin des Boveresses 155, 1066, Epalinges, Switzerland
| | - C Pot
- Laboratories of Neuroimmunology, Neuroscience Research Center and Service of Neurology, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Chemin des Boveresses 155, 1066, Epalinges, Switzerland.
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Milich LM, Ryan CB, Lee JK. The origin, fate, and contribution of macrophages to spinal cord injury pathology. Acta Neuropathol 2019; 137:785-797. [PMID: 30929040 PMCID: PMC6510275 DOI: 10.1007/s00401-019-01992-3] [Citation(s) in RCA: 156] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 03/11/2019] [Accepted: 03/12/2019] [Indexed: 12/16/2022]
Abstract
Virtually all phases of spinal cord injury pathogenesis, including inflammation, cell proliferation and differentiation, as well as tissue remodeling, are mediated in part by infiltrating monocyte-derived macrophages. It is now clear that these infiltrating macrophages have distinct functions from resident microglia and are capable of mediating both harmful and beneficial effects after injury. These divergent effects have been largely attributed to environmental cues, such as specific cytokines, that influence the macrophage polarization state. In this review, we also consider the possibility that different macrophage origins, including the spleen, bone marrow, and local self-renewal, may also affect macrophage fate, and ultimately their function that contribute to the complex pathobiology of spinal cord injury.
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Affiliation(s)
- Lindsay M Milich
- Miami Project to Cure Paralysis, Department of Neurological Surgery, University of Miami School of Medicine, Miami, FL, 33136, USA
| | - Christine B Ryan
- Miami Project to Cure Paralysis, Department of Neurological Surgery, University of Miami School of Medicine, Miami, FL, 33136, USA
| | - Jae K Lee
- Miami Project to Cure Paralysis, Department of Neurological Surgery, University of Miami School of Medicine, Miami, FL, 33136, USA.
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Altinoz MA, Ozpinar A. PPAR-δ and erucic acid in multiple sclerosis and Alzheimer's Disease. Likely benefits in terms of immunity and metabolism. Int Immunopharmacol 2019; 69:245-256. [DOI: 10.1016/j.intimp.2019.01.057] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 01/09/2019] [Accepted: 01/31/2019] [Indexed: 12/17/2022]
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Dietary Sargassum fusiforme improves memory and reduces amyloid plaque load in an Alzheimer's disease mouse model. Sci Rep 2019; 9:4908. [PMID: 30894635 PMCID: PMC6426980 DOI: 10.1038/s41598-019-41399-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 03/05/2019] [Indexed: 12/12/2022] Open
Abstract
Activation of liver X receptors (LXRs) by synthetic agonists was found to improve cognition in Alzheimer's disease (AD) mice. However, these LXR agonists induce hypertriglyceridemia and hepatic steatosis, hampering their use in the clinic. We hypothesized that phytosterols as LXR agonists enhance cognition in AD without affecting plasma and hepatic triglycerides. Phytosterols previously reported to activate LXRs were tested in a luciferase-based LXR reporter assay. Using this assay, we found that phytosterols commonly present in a Western type diet in physiological concentrations do not activate LXRs. However, a lipid extract of the 24(S)-Saringosterol-containing seaweed Sargassum fusiforme did potently activate LXRβ. Dietary supplementation of crude Sargassum fusiforme or a Sargassum fusiforme-derived lipid extract to AD mice significantly improved short-term memory and reduced hippocampal Aβ plaque load by 81%. Notably, none of the side effects typically induced by full synthetic LXR agonists were observed. In contrast, administration of the synthetic LXRα activator, AZ876, did not improve cognition and resulted in the accumulation of lipid droplets in the liver. Administration of Sargassum fusiforme-derived 24(S)-Saringosterol to cultured neurons reduced the secretion of Aβ42. Moreover, conditioned medium from 24(S)-Saringosterol-treated astrocytes added to microglia increased phagocytosis of Aβ. Our data show that Sargassum fusiforme improves cognition and alleviates AD pathology. This may be explained at least partly by 24(S)-Saringosterol-mediated LXRβ activation.
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Fakan B, Szalardy L, Vecsei L. Exploiting the Therapeutic Potential of Endogenous Immunomodulatory Systems in Multiple Sclerosis-Special Focus on the Peroxisome Proliferator-Activated Receptors (PPARs) and the Kynurenines. Int J Mol Sci 2019; 20:ijms20020426. [PMID: 30669473 PMCID: PMC6358998 DOI: 10.3390/ijms20020426] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 01/13/2019] [Accepted: 01/15/2019] [Indexed: 01/20/2023] Open
Abstract
Multiple sclerosis (MS) is a progressive neurodegenerative disease, characterized by autoimmune central nervous system (CNS) demyelination attributable to a disturbed balance between encephalitic T helper 1 (Th1) and T helper 17 (Th17) and immunomodulatory regulatory T cell (Treg) and T helper 2 (Th2) cells, and an alternatively activated macrophage (M2) excess. Endogenous molecular systems regulating these inflammatory processes have recently been investigated to identify molecules that can potentially influence the course of the disease. These include the peroxisome proliferator-activated receptors (PPARs), PPARγ coactivator-1alpha (PGC-1α), and kynurenine pathway metabolites. Although all PPARs ameliorate experimental autoimmune encephalomyelitis (EAE), recent evidence suggests that PPARα, PPARβ/δ agonists have less pronounced immunomodulatory effects and, along with PGC-1α, are not biomarkers of neuroinflammation in contrast to PPARγ. Small clinical trials with PPARγ agonists have been published with positive results. Proposed as immunomodulatory and neuroprotective, the therapeutic use of PGC-1α activation needs to be assessed in EAE/MS. The activation of indolamine 2,3-dioxygenase (IDO), the rate-limiting step of the kynurenine pathway of tryptophan (Trp) metabolism, plays crucial immunomodulatory roles. Indeed, Trp metabolites have therapeutic relevance in EAE and drugs with structural analogy to kynurenines, such as teriflunomide, are already approved for MS. Further studies are required to gain deeper knowledge of such endogenous immunomodulatory pathways with potential therapeutic implications in MS.
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Affiliation(s)
- Bernadett Fakan
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, H-6725 Szeged, Semmelweis u. 6, Hungary.
| | - Levente Szalardy
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, H-6725 Szeged, Semmelweis u. 6, Hungary.
| | - Laszlo Vecsei
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, H-6725 Szeged, Semmelweis u. 6, Hungary.
- MTA-SZTE Neuroscience Research Group, H-6725 Szeged, Semmelweis u. 6, Hungary.
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Grajchen E, Hendriks JJA, Bogie JFJ. The physiology of foamy phagocytes in multiple sclerosis. Acta Neuropathol Commun 2018; 6:124. [PMID: 30454040 PMCID: PMC6240956 DOI: 10.1186/s40478-018-0628-8] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 11/02/2018] [Indexed: 12/15/2022] Open
Abstract
Multiple sclerosis (MS) is a chronic disease of the central nervous system characterized by massive infiltration of immune cells, demyelination, and axonal loss. Active MS lesions mainly consist of macrophages and microglia containing abundant intracellular myelin remnants. Initial studies showed that these foamy phagocytes primarily promote MS disease progression by internalizing myelin debris, presenting brain-derived autoantigens, and adopting an inflammatory phenotype. However, more recent studies indicate that phagocytes can also adopt a beneficial phenotype upon myelin internalization. In this review, we summarize and discuss the current knowledge on the spatiotemporal physiology of foamy phagocytes in MS lesions, and elaborate on extrinsic and intrinsic factors regulating their behavior. In addition, we discuss and link the physiology of myelin-containing phagocytes to that of foamy macrophages in other disorders such atherosclerosis.
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Affiliation(s)
- Elien Grajchen
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium/School of Life Sciences, Transnationale Universiteit Limburg, Diepenbeek, Belgium
| | - Jerome J A Hendriks
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium/School of Life Sciences, Transnationale Universiteit Limburg, Diepenbeek, Belgium
| | - Jeroen F J Bogie
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium/School of Life Sciences, Transnationale Universiteit Limburg, Diepenbeek, Belgium.
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Metabolic Dysfunction and Peroxisome Proliferator-Activated Receptors (PPAR) in Multiple Sclerosis. Int J Mol Sci 2018; 19:ijms19061639. [PMID: 29865151 PMCID: PMC6032172 DOI: 10.3390/ijms19061639] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 05/27/2018] [Accepted: 05/28/2018] [Indexed: 02/06/2023] Open
Abstract
Multiple sclerosis (MS) is an inflammatory and neurodegenerative disease of the central nervous system (CNS) probably caused, in most cases, by the interaction of genetic and environmental factors. This review first summarizes some clinical, epidemiological and pathological characteristics of MS. Then, the involvement of biochemical pathways is discussed in the development and repair of the CNS lesions and the immune dysfunction in the disease. Finally, the potential roles of peroxisome proliferator-activated receptors (PPAR) in MS are discussed. It is suggested that metabolic mechanisms modulated by PPAR provide a window to integrate the systemic and neurological events underlying the pathogenesis of the disease. In conclusion, the reviewed data highlight molecular avenues of understanding MS that may open new targets for improved therapies and preventive strategies for the disease.
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Matveeva O, Bogie JFJ, Hendriks JJA, Linker RA, Haghikia A, Kleinewietfeld M. Western lifestyle and immunopathology of multiple sclerosis. Ann N Y Acad Sci 2018; 1417:71-86. [PMID: 29377214 PMCID: PMC5947729 DOI: 10.1111/nyas.13583] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 11/16/2017] [Accepted: 11/27/2017] [Indexed: 12/16/2022]
Abstract
There is increasing evidence for a sudden and unprecedented rise in the incidence of multiple sclerosis (MS) in Westernized countries over the past decades, emphasizing the role of environmental factors. Among many candidates, rapid changes in dietary habits seem to play a role in the pathogenesis of MS. Here, we summarize and discuss the available evidence for the role of dietary nutrients, such as table salt, fatty acids, and flavonoids, in the development and pathogenesis of MS. We also discuss new and emerging risk factors accompanying Western lifestyle, such as shift work, sleep, and circadian disruption.
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Affiliation(s)
- Olga Matveeva
- VIB Laboratory of Translational Immunomodulation, Center for Inflammation Research, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Jeroen F J Bogie
- Department of Neuroimmunology, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Jerome J A Hendriks
- Department of Neuroimmunology, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Ralf A Linker
- Department of Neurology, University Hospital Erlangen, Friedrich-Alexander-University (FAU) Erlangen-Nuremberg, Erlangen, Germany
| | - Aiden Haghikia
- Department of Neurology, Ruhr-University Bochum, Bochum, Germany
| | - Markus Kleinewietfeld
- VIB Laboratory of Translational Immunomodulation, Center for Inflammation Research, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
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42
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Mailleux J, Timmermans S, Nelissen K, Vanmol J, Vanmierlo T, van Horssen J, Bogie JFJ, Hendriks JJA. Low-Density Lipoprotein Receptor Deficiency Attenuates Neuroinflammation through the Induction of Apolipoprotein E. Front Immunol 2017; 8:1701. [PMID: 29276512 PMCID: PMC5727422 DOI: 10.3389/fimmu.2017.01701] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 11/17/2017] [Indexed: 12/24/2022] Open
Abstract
Objective We aimed to determine the role of the low-density lipoprotein receptor (LDLr) in neuroinflammation by inducing experimental autoimmune encephalomyelitis (EAE) in ldlr knock out mice. Methods MOG35-55 induced EAE in male and female ldlr-/- mice was assessed clinically and histopathologically. Expression of inflammatory mediators and apolipoprotein E (apoE) was investigated by qPCR. Changes in protein levels of apoE and tumor necrosis factor alpha (TNFα) were validated by western blot and ELISA, respectively. Results Ldlr-/--attenuated EAE disease severity in female, but not in male, EAE mice marked by a reduced proinflammatory cytokine production in the central nervous system of female ldlr-/- mice. Macrophages from female ldlr-/- mice showed a similar decrease in proinflammatory mediators, an impaired capacity to phagocytose myelin and enhanced secretion of the anti-inflammatory apoE. Interestingly, apoE/ldlr double knock out abrogated the beneficial effect of ldlr depletion in EAE. Conclusion Collectively, we show that ldlr-/- reduces EAE disease severity in female but not in male EAE mice, and that this can be explained by increased levels of apoE in female ldlr-/- mice. Although the reason for the observed sexual dimorphism remains unclear, our findings show that LDLr and associated apoE levels are involved in neuroinflammatory processes.
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Affiliation(s)
- Jo Mailleux
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Silke Timmermans
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | | | - Jasmine Vanmol
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Tim Vanmierlo
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Jack van Horssen
- Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, Netherlands
| | - Jeroen F J Bogie
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
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Amici SA, Dong J, Guerau-de-Arellano M. Molecular Mechanisms Modulating the Phenotype of Macrophages and Microglia. Front Immunol 2017; 8:1520. [PMID: 29176977 PMCID: PMC5686097 DOI: 10.3389/fimmu.2017.01520] [Citation(s) in RCA: 126] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 10/26/2017] [Indexed: 12/24/2022] Open
Abstract
Macrophages and microglia play crucial roles during central nervous system development, homeostasis and acute events such as infection or injury. The diverse functions of tissue macrophages and microglia are mirrored by equally diverse phenotypes. A model of inflammatory/M1 versus a resolution phase/M2 macrophages has been widely used. However, the complexity of macrophage function can only be achieved by the existence of varied, plastic and tridimensional macrophage phenotypes. Understanding how tissue macrophages integrate environmental signals via molecular programs to define pathogen/injury inflammatory responses provides an opportunity to better understand the multilayered nature of macrophages, as well as target and modulate cellular programs to control excessive inflammation. This is particularly important in MS and other neuroinflammatory diseases, where chronic inflammatory macrophage and microglial responses may contribute to pathology. Here, we perform a comprehensive review of our current understanding of how molecular pathways modulate tissue macrophage phenotype, covering both classic pathways and the emerging role of microRNAs, receptor-tyrosine kinases and metabolism in macrophage phenotype. In addition, we discuss pathway parallels in microglia, novel markers helpful in the identification of peripheral macrophages versus microglia and markers linked to their phenotype.
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Affiliation(s)
- Stephanie A Amici
- School of Health and Rehabilitation Sciences, Division of Medical Laboratory Science, College of Medicine, Wexner Medical Center, The Ohio State University, Columbus, OH, United States
| | - Joycelyn Dong
- School of Health and Rehabilitation Sciences, Division of Medical Laboratory Science, College of Medicine, Wexner Medical Center, The Ohio State University, Columbus, OH, United States.,McCormick School of Engineering, Division of Biomedical Engineering, Northwestern University, Evanston, IL, United States
| | - Mireia Guerau-de-Arellano
- School of Health and Rehabilitation Sciences, Division of Medical Laboratory Science, College of Medicine, Wexner Medical Center, The Ohio State University, Columbus, OH, United States.,Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, United States.,Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, United States.,Department of Neuroscience, The Ohio State University, Columbus, OH, United States
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44
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Healy LM, Jang JH, Won SY, Lin YH, Touil H, Aljarallah S, Bar-Or A, Antel JP. MerTK-mediated regulation of myelin phagocytosis by macrophages generated from patients with MS. NEUROLOGY(R) NEUROIMMUNOLOGY & NEUROINFLAMMATION 2017; 4:e402. [PMID: 29379818 PMCID: PMC5777663 DOI: 10.1212/nxi.0000000000000402] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 08/09/2017] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To document functional differences between monocyte-derived macrophages (MDMs) of patients with MS and the ability of age/sex-matched healthy donor cells to phagocytose human myelin and to investigate the molecular mechanisms that underlie this. METHODS MDMs were derived from peripheral blood monocytes of 25 untreated patients with relapsing-remitting MS and secondary progressive MS and age/sex-matched healthy controls (HCs). Phagocytosis was assessed by flow cytometry using fluorescently labeled human myelin. Quantification of messenger RNA and protein expression of Tyro3, Axl, and MerTK family molecules was determined by quantitative PCR, Western blotting, and flow cytometry. RESULTS Cells of patients with MS display a reduced ability to phagocytose human myelin but not red blood cells as compared to matched HCs. These cells express significantly lower levels of the phagocytic tyrosine kinase receptor, MerTK, and its natural ligand, growth arrest-specific 6, independently of the activation state of the cells. Increased expression of interleukin 10 following myelin uptake by healthy donor cells is lost in MDMs of patients with MS; this effect is mediated through the MerTK pathway. Treatment of MS cells with transforming growth factor β (TGFβ) restored both phagocytosis and expression deficits. CONCLUSIONS We describe a molecular mechanism that underlies a defect in myelin phagocytosis by macrophages generated from patients with MS. This abnormality involves decreased expression of MerTK and its ligands and can be rescued by treatment with TGFβ.
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Affiliation(s)
- Luke M Healy
- Neuroimmunology Unit (L.M.H., J.H.J., S.-Y.W., Y.H.L., H.T., S.A., A.B.-O., J.P.A.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Multiple Sclerosis Division (A.B.-O.), Department of Neurology and Center for Neuroinflammation and Neurotherapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Jeong Ho Jang
- Neuroimmunology Unit (L.M.H., J.H.J., S.-Y.W., Y.H.L., H.T., S.A., A.B.-O., J.P.A.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Multiple Sclerosis Division (A.B.-O.), Department of Neurology and Center for Neuroinflammation and Neurotherapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - So-Yoon Won
- Neuroimmunology Unit (L.M.H., J.H.J., S.-Y.W., Y.H.L., H.T., S.A., A.B.-O., J.P.A.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Multiple Sclerosis Division (A.B.-O.), Department of Neurology and Center for Neuroinflammation and Neurotherapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Yun Hsuan Lin
- Neuroimmunology Unit (L.M.H., J.H.J., S.-Y.W., Y.H.L., H.T., S.A., A.B.-O., J.P.A.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Multiple Sclerosis Division (A.B.-O.), Department of Neurology and Center for Neuroinflammation and Neurotherapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Hanane Touil
- Neuroimmunology Unit (L.M.H., J.H.J., S.-Y.W., Y.H.L., H.T., S.A., A.B.-O., J.P.A.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Multiple Sclerosis Division (A.B.-O.), Department of Neurology and Center for Neuroinflammation and Neurotherapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Salman Aljarallah
- Neuroimmunology Unit (L.M.H., J.H.J., S.-Y.W., Y.H.L., H.T., S.A., A.B.-O., J.P.A.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Multiple Sclerosis Division (A.B.-O.), Department of Neurology and Center for Neuroinflammation and Neurotherapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Amit Bar-Or
- Neuroimmunology Unit (L.M.H., J.H.J., S.-Y.W., Y.H.L., H.T., S.A., A.B.-O., J.P.A.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Multiple Sclerosis Division (A.B.-O.), Department of Neurology and Center for Neuroinflammation and Neurotherapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Jack P Antel
- Neuroimmunology Unit (L.M.H., J.H.J., S.-Y.W., Y.H.L., H.T., S.A., A.B.-O., J.P.A.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Multiple Sclerosis Division (A.B.-O.), Department of Neurology and Center for Neuroinflammation and Neurotherapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia
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45
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Crosstalk with Inflammatory Macrophages Shapes the Regulatory Properties of Multipotent Adult Progenitor Cells. Stem Cells Int 2017; 2017:2353240. [PMID: 28785285 PMCID: PMC5529661 DOI: 10.1155/2017/2353240] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 05/27/2017] [Accepted: 06/12/2017] [Indexed: 01/25/2023] Open
Abstract
Macrophages and microglia are key effector cells in immune-mediated neuroinflammatory disorders. Driving myeloid cells towards an anti-inflammatory, tissue repair-promoting phenotype is considered a promising strategy to halt neuroinflammation and promote central nervous system (CNS) repair. In this study, we defined the impact of multipotent adult progenitor cells (MAPC), a stem cell population sharing common mesodermal origin with mesenchymal stem cells (MSCs), on the phenotype of macrophages and the reciprocal interactions between these two cell types. We show that MAPC suppress the secretion of tumor necrosis factor alpha (TNF-α) by inflammatory macrophages partially through a cyclooxygenase 2- (COX-2-) dependent mechanism. In turn, we demonstrate that inflammatory macrophages trigger the immunomodulatory properties of MAPC, including an increased expression of immunomodulatory mediators (e.g., inducible nitric oxide synthase (iNOS) and COX-2), chemokines, and chemokine receptors. Macrophage-primed MAPC secrete soluble factors that suppress TNF-α release by macrophages. Moreover, the MAPC secretome suppresses the antigen-specific proliferation of autoreactive T cells and the T cell stimulatory capacity of macrophages. Finally, MAPC increase their motility towards secreted factors of activated macrophages. Collectively, these in vitro findings reveal intimate reciprocal interactions between MAPC and inflammatory macrophages, which are of importance in the design of MAPC-based therapeutic strategies for neuroinflammatory disorders in which myeloid cells play a crucial role.
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46
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Kopper TJ, Gensel JC. Myelin as an inflammatory mediator: Myelin interactions with complement, macrophages, and microglia in spinal cord injury. J Neurosci Res 2017; 96:969-977. [PMID: 28696010 DOI: 10.1002/jnr.24114] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 06/02/2017] [Accepted: 06/19/2017] [Indexed: 12/24/2022]
Abstract
Spinal cord injury (SCI) triggers chronic intraspinal inflammation consisting of activated resident and infiltrating immune cells (especially microglia/macrophages). The environmental factors contributing to this protracted inflammation are not well understood; however, myelin lipid debris is a hallmark of SCI. Myelin is also a potent macrophage stimulus and target of complement-mediated clearance and inflammation. The downstream effects of these neuroimmune interactions have the potential to contribute to ongoing pathology or facilitate repair. This depends in large part on whether myelin drives pathological or reparative macrophage activation states, commonly referred to as M1 (proinflammatory) or M2 (alternatively) macrophages, respectively. Here we review the processes by which myelin debris may be cleared through macrophage surface receptors and the complement system, how this differentially influences macrophage and microglial activation states, and how the cellular functions of these myelin macrophages and complement proteins contribute to chronic inflammation and secondary injury after SCI.
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Affiliation(s)
- Timothy J Kopper
- Spinal Cord and Brain Injury Research Center, Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky
| | - John C Gensel
- Spinal Cord and Brain Injury Research Center, Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky
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47
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TLR4 Deficiency Impairs Oligodendrocyte Formation in the Injured Spinal Cord. J Neurosci 2017; 36:6352-64. [PMID: 27277810 DOI: 10.1523/jneurosci.0353-16.2016] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 05/05/2016] [Indexed: 12/12/2022] Open
Abstract
UNLABELLED Acute oligodendrocyte (OL) death after traumatic spinal cord injury (SCI) is followed by robust neuron-glial antigen 2 (NG2)-positive OL progenitor proliferation and differentiation into new OLs. Inflammatory mediators are prevalent during both phases and can influence the fate of NG2 cells and OLs. Specifically, toll-like receptor (TLR) 4 signaling induces OL genesis in the naive spinal cord, and lack of TLR4 signaling impairs white matter sparing and functional recovery after SCI. Therefore, we hypothesized that TLR4 signaling may regulate oligodendrogenesis after SCI. C3H/HeJ (TLR4-deficient) and control (C3H/HeOuJ) mice received a moderate midthoracic spinal contusion. TLR4-deficient mice showed worse functional recovery and reduced OL numbers compared with controls at 24 h after injury through chronic time points. Acute OL loss was accompanied by reduced ferritin expression, which is regulated by TLR4 and needed for effective iron storage. TLR4-deficient injured spinal cords also displayed features consistent with reduced OL genesis, including reduced NG2 expression, fewer BrdU-positive OLs, altered BMP4 signaling and inhibitor of differentiation 4 (ID4) expression, and delayed myelin phagocytosis. Expression of several factors, including IGF-1, FGF2, IL-1β, and PDGF-A, was altered in TLR4-deficient injured spinal cords compared with wild types. Together, these data show that TLR4 signaling after SCI is important for OL lineage cell sparing and replacement, as well as in regulating cytokine and growth factor expression. These results highlight new roles for TLR4 in endogenous SCI repair and emphasize that altering the function of a single immune-related receptor can dramatically change the reparative responses of multiple cellular constituents in the injured CNS milieu. SIGNIFICANCE STATEMENT Myelinating cells of the CNS [oligodendrocytes (OLs)] are killed for several weeks after traumatic spinal cord injury (SCI), but they are replaced by resident progenitor cells. How the concurrent inflammatory signaling affects this endogenous reparative response is unclear. Here, we provide evidence that immune receptor toll-like receptor 4 (TLR4) supports OL lineage cell sparing, long-term OL and OL progenitor replacement, and chronic functional recovery. We show that TLR4 signaling is essential for acute iron storage, regulating cytokine and growth factor expression, and efficient myelin debris clearance, all of which influence OL replacement. Importantly, the current study reveals that a single immune receptor is essential for repair responses after SCI, and the potential mechanisms of this beneficial effect likely change over time after injury.
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48
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Szalardy L, Zadori D, Bencsik K, Vecsei L, Klivenyi P. Unlike PPARgamma, neither other PPARs nor PGC-1alpha is elevated in the cerebrospinal fluid of patients with multiple sclerosis. Neurosci Lett 2017; 651:128-133. [PMID: 28483651 DOI: 10.1016/j.neulet.2017.05.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 05/05/2017] [Accepted: 05/05/2017] [Indexed: 02/06/2023]
Abstract
Corroborating with prior experimental findings, we recently reported the pronounced elevation of peroxisome proliferator-activated receptor gamma (PPARγ) protein concentration in the cerebrospinal fluid (CSF) of patients with multiple sclerosis (MS), in association with neuroinflammatory markers and clinical severity. Based on subsequent reports on the possible involvement of other PPARs and PPARγ coactivator-1alpha (PGC-1α) in neuroinflammation in MS, we analyzed the protein levels of PPARα, PPARβ/δ, and PGC-1α in a subset of CSF samples from the same cohort of relapsing-remitting MS patients. Unlike PPARγ, none of these proteins were found elevated in MS patients (n=25) compared to non-inflammatory controls (n=16), with the levels of PPARα and PPARβ/δ found generally below the limit of detection, and that of PGC-1α being detectable but comparable in both groups. The clinical and laboratory associations previously reported with PPARγ were however significant even in this smaller subset. The potential underlying causes of these differential alterations are discussed. The findings suggest that despite their proposed involvement in the regulation of inflammatory processes in MS, PPARα, PPARβ/δ, and PGC-1α proteins are not potential biomarkers of neuroinflammation in MS, and indicate a preferential role of PPARγ in the endogenous regulation of autoimmune response in the human CNS within its receptor family.
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Affiliation(s)
- Levente Szalardy
- Department of Neurology, University of Szeged, H-6725, Szeged, Semmelweis u. 6, Hungary
| | - Denes Zadori
- Department of Neurology, University of Szeged, H-6725, Szeged, Semmelweis u. 6, Hungary
| | - Krisztina Bencsik
- Department of Neurology, University of Szeged, H-6725, Szeged, Semmelweis u. 6, Hungary
| | - Laszlo Vecsei
- Department of Neurology, University of Szeged, H-6725, Szeged, Semmelweis u. 6, Hungary; MTA-SZTE Neuroscience Research Group, H-6725, Szeged, Semmelweis u. 6, Hungary
| | - Peter Klivenyi
- Department of Neurology, University of Szeged, H-6725, Szeged, Semmelweis u. 6, Hungary.
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49
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Bogie JFJ, Mailleux J, Wouters E, Jorissen W, Grajchen E, Vanmol J, Wouters K, Hellings N, van Horssen J, Vanmierlo T, Hendriks JJA. Scavenger receptor collectin placenta 1 is a novel receptor involved in the uptake of myelin by phagocytes. Sci Rep 2017; 7:44794. [PMID: 28317919 PMCID: PMC5357964 DOI: 10.1038/srep44794] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 02/14/2017] [Indexed: 11/09/2022] Open
Abstract
Myelin-containing macrophages and microglia are the most abundant immune cells in active multiple sclerosis (MS) lesions. Our recent transcriptomic analysis demonstrated that collectin placenta 1 (CL-P1) is one of the most potently induced genes in macrophages after uptake of myelin. CL-P1 is a type II transmembrane protein with both a collagen-like and carbohydrate recognition domain, which plays a key role in host defense. In this study we sought to determine the dynamics of CL-P1 expression on myelin-containing phagocytes and define the role that it plays in MS lesion development. We show that myelin uptake increases the cell surface expression of CL-P1 by mouse and human macrophages, but not by primary mouse microglia in vitro. In active demyelinating MS lesions, CL-P1 immunoreactivity was localized to perivascular and parenchymal myelin-laden phagocytes. Finally, we demonstrate that CL-P1 is involved in myelin internalization as knockdown of CL-P1 markedly reduced myelin uptake. Collectively, our data indicate that CL-P1 is a novel receptor involved in myelin uptake by phagocytes and likely plays a role in MS lesion development.
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Affiliation(s)
- Jeroen F J Bogie
- Biomedical Research Institute, Hasselt University/Transnational University Limburg, School of Life Sciences, Diepenbeek, Belgium
| | - Jo Mailleux
- Biomedical Research Institute, Hasselt University/Transnational University Limburg, School of Life Sciences, Diepenbeek, Belgium
| | - Elien Wouters
- Biomedical Research Institute, Hasselt University/Transnational University Limburg, School of Life Sciences, Diepenbeek, Belgium
| | - Winde Jorissen
- Biomedical Research Institute, Hasselt University/Transnational University Limburg, School of Life Sciences, Diepenbeek, Belgium
| | - Elien Grajchen
- Biomedical Research Institute, Hasselt University/Transnational University Limburg, School of Life Sciences, Diepenbeek, Belgium
| | - Jasmine Vanmol
- Biomedical Research Institute, Hasselt University/Transnational University Limburg, School of Life Sciences, Diepenbeek, Belgium
| | - Kristiaan Wouters
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre (MUMC), Maastricht, The Netherlands.,Department of Internal Medicine, Maastricht University Medical Centre (MUMC), Maastricht, The Netherlands
| | - Niels Hellings
- Biomedical Research Institute, Hasselt University/Transnational University Limburg, School of Life Sciences, Diepenbeek, Belgium
| | - Jack van Horssen
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands
| | - Tim Vanmierlo
- Biomedical Research Institute, Hasselt University/Transnational University Limburg, School of Life Sciences, Diepenbeek, Belgium
| | - Jerome J A Hendriks
- Biomedical Research Institute, Hasselt University/Transnational University Limburg, School of Life Sciences, Diepenbeek, Belgium
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50
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Bogie JFJ, Boelen E, Louagie E, Delputte P, Elewaut D, van Horssen J, Hendriks JJA, Hellings N. CD169 is a marker for highly pathogenic phagocytes in multiple sclerosis. Mult Scler 2017; 24:290-300. [DOI: 10.1177/1352458517698759] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Background: Phagocytes, such as macrophages and microglia, are key effector cells in the pathophysiology of multiple sclerosis (MS). It is widely accepted that they instigate and promote neuroinflammatory and neurodegenerative events in MS. An increasing amount of studies indicate that Siglec-1, also known CD169, is a marker for activated phagocytes in inflammatory disorders. Objective: In this study, we set out to define how CD169+ phagocytes contribute to neuroinflammation in MS. Methods: CD169-diphtheria toxin receptor (DTR) mice, which express human DTR under control of the CD169 promoter, were used to define the impact of CD169+ cells on neuroinflammation. Flow cytometry and immunohistochemistry were utilized to determine the expression and distribution of CD169. Results: We show that CD169 is highly expressed by lesional and circulating phagocytes in MS and experimental autoimmune encephalomyelitis (EAE). Our data further indicate that CD169 represents a selective marker for early activated microglia in MS and EAE lesions. Depletion of CD169+ cells markedly reduced neuroinflammation and ameliorated disease symptoms in EAE-affected mice. Conclusion: Our findings indicate that CD169+ cells promote neuroinflammation. Furthermore, they suggest that CD169+ phagocytes play a key role in the pathophysiology of MS. Hence, targeting CD169+ phagocytes may hold therapeutic value for MS.
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Affiliation(s)
- Jeroen FJ Bogie
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium/School of Life Sciences, Transnationale Universiteit Limburg, Diepenbeek, Belgium
| | - Ellen Boelen
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium/School of Life Sciences, Transnationale Universiteit Limburg, Diepenbeek, Belgium
| | - Els Louagie
- Department of Rheumatology, Ghent University Hospital, Ghent, Belgium/Unit for Molecular Immunology and Inflammation, VIB Inflammation Research Center, Ghent University, Ghent, Belgium
| | - Peter Delputte
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Dirk Elewaut
- Department of Rheumatology, Ghent University Hospital, Ghent, Belgium/Unit for Molecular Immunology and Inflammation, VIB Inflammation Research Center, Ghent University, Ghent, Belgium
| | - Jack van Horssen
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium/School of Life Sciences, Transnationale Universiteit Limburg, Diepenbeek, Belgium/Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands
| | - Jerome JA Hendriks
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium/School of Life Sciences, Transnationale Universiteit Limburg, Diepenbeek, Belgium
| | - Niels Hellings
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium/School of Life Sciences, Transnationale Universiteit Limburg, Diepenbeek, Belgium
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