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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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2
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De Paula GC, Aldana BI, Battistella R, Fernández-Calle R, Bjure A, Lundgaard I, Deierborg T, Duarte JMN. Extracellular vesicles released from microglia after palmitate exposure impact brain function. J Neuroinflammation 2024; 21:173. [PMID: 39014461 DOI: 10.1186/s12974-024-03168-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 07/09/2024] [Indexed: 07/18/2024] Open
Abstract
Dietary patterns that include an excess of foods rich in saturated fat are associated with brain dysfunction. Although microgliosis has been proposed to play a key role in the development of brain dysfunction in diet-induced obesity (DIO), neuroinflammation with cytokine over-expression is not always observed. Thus, mechanisms by which microglia contribute to brain impairment in DIO are uncertain. Using the BV2 cell model, we investigated the gliosis profile of microglia exposed to palmitate (200 µmol/L), a saturated fatty acid abundant in high-fat diet and in the brain of obese individuals. We observed that microglia respond to a 24-hour palmitate exposure with increased proliferation, and with a metabolic network rearrangement that favors energy production from glycolysis rather than oxidative metabolism, despite stimulated mitochondria biogenesis. In addition, while palmitate did not induce increased cytokine expression, it modified the protein cargo of released extracellular vesicles (EVs). When administered intra-cerebroventricularly to mice, EVs secreted from palmitate-exposed microglia in vitro led to memory impairment, depression-like behavior, and glucose intolerance, when compared to mice receiving EVs from vehicle-treated microglia. We conclude that microglia exposed to palmitate can mediate brain dysfunction through the cargo of shed EVs.
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Affiliation(s)
- Gabriela C De Paula
- Department of Experimental Medical Science (EMV), Faculty of Medicine, Lund University, Sölvegatan 19, BMC C11, Lund, 221 84, Sweden
- Wallenberg Centre for Molecular Medicine, Lund University, Lund, Sweden
| | - Blanca I Aldana
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Roberta Battistella
- Department of Experimental Medical Science (EMV), Faculty of Medicine, Lund University, Sölvegatan 19, BMC C11, Lund, 221 84, Sweden
- Wallenberg Centre for Molecular Medicine, Lund University, Lund, Sweden
| | - Rosalía Fernández-Calle
- Department of Experimental Medical Science (EMV), Faculty of Medicine, Lund University, Sölvegatan 19, BMC C11, Lund, 221 84, Sweden
| | - Andreas Bjure
- Department of Experimental Medical Science (EMV), Faculty of Medicine, Lund University, Sölvegatan 19, BMC C11, Lund, 221 84, Sweden
| | - Iben Lundgaard
- Department of Experimental Medical Science (EMV), Faculty of Medicine, Lund University, Sölvegatan 19, BMC C11, Lund, 221 84, Sweden
- Wallenberg Centre for Molecular Medicine, Lund University, Lund, Sweden
| | - Tomas Deierborg
- Department of Experimental Medical Science (EMV), Faculty of Medicine, Lund University, Sölvegatan 19, BMC C11, Lund, 221 84, Sweden
- Wallenberg Centre for Molecular Medicine, Lund University, Lund, Sweden
| | - João M N Duarte
- Department of Experimental Medical Science (EMV), Faculty of Medicine, Lund University, Sölvegatan 19, BMC C11, Lund, 221 84, Sweden.
- Wallenberg Centre for Molecular Medicine, Lund University, Lund, Sweden.
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3
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Grijaldo-Alvarez SJB, Alvarez MRS, Schindler RL, Oloumi A, Hernandez N, Seales T, Angeles JGC, Nacario RC, Completo GC, Zivkovic AM, Bruce German J, Lebrilla CB. N-Glycan profile of the cell membrane as a probe for lipopolysaccharide-induced microglial neuroinflammation uncovers the effects of common fatty acid supplementation. Food Funct 2024. [PMID: 39011570 DOI: 10.1039/d4fo01598c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
Altered N-glycosylation of proteins on the cell membrane is associated with several neurodegenerative diseases. Microglia are an ideal model for studying glycosylation and neuroinflammation, but whether aberrant N-glycosylation in microglia can be restored by diet remains unknown. Herein, we profiled the N-glycome, proteome, and glycoproteome of the human microglia following lipopolysaccharide (LPS) induction to probe the impact of dietary and gut microbe-derived fatty acids-oleic acid, lauric acid, palmitic acid, valeric acid, butyric acid, isobutyric acid, and propionic acid-on neuroinflammation using liquid chromatography-tandem mass spectrometry. LPS changed N-glycosylation in the microglial glycocalyx altering high mannose and sialofucosylated N-glycans, suggesting the dysregulation of mannosidases, fucosyltransferases, and sialyltransferases. The results were consistent as we observed the restoration effect of the fatty acids, especially oleic acid, on the LPS-treated microglia, specifically on the high mannose and sialofucosylated glycoforms of translocon-associated proteins, SSRA and SSRB along with the cell surface proteins, CD63 and CD166. In addition, proteomic analysis and in silico modeling substantiated the potential of fatty acids in reverting the effects of LPS on microglial N-glycosylation. Our results showed that N-glycosylation is likely affected by diet by restoring alterations following LPS challenge, which may then influence the disease state.
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Affiliation(s)
- Sheryl Joyce B Grijaldo-Alvarez
- Department of Chemistry, University of California, Davis, 95616, USA.
- Institute of Chemistry, University of the Philippines Los Baños, Philippines, 4031.
| | | | | | - Armin Oloumi
- Department of Chemistry, University of California, Davis, 95616, USA.
| | - Noah Hernandez
- Department of Chemistry, University of California, Davis, 95616, USA.
| | - Tristan Seales
- Department of Chemistry, University of California, Davis, 95616, USA.
| | - Jorge Gil C Angeles
- Philippine Genome Center - Program for Agriculture, Livestock, Fisheries and Forestry, University of the Philippines Los Baños, Philippines, 4031.
| | - Ruel C Nacario
- Institute of Chemistry, University of the Philippines Los Baños, Philippines, 4031.
| | - Gladys C Completo
- Institute of Chemistry, University of the Philippines Los Baños, Philippines, 4031.
| | - Angela M Zivkovic
- Department of Nutrition, University of California, Davis, 95616, USA.
| | - J Bruce German
- Department of Food Science and Technology, University of California, Davis, 95616, USA.
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4
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Chausse B, Malorny N, Lewen A, Poschet G, Berndt N, Kann O. Metabolic flexibility ensures proper neuronal network function in moderate neuroinflammation. Sci Rep 2024; 14:14405. [PMID: 38909138 PMCID: PMC11193723 DOI: 10.1038/s41598-024-64872-1] [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: 12/22/2023] [Accepted: 06/13/2024] [Indexed: 06/24/2024] Open
Abstract
Microglia, brain-resident macrophages, can acquire distinct functional phenotypes, which are supported by differential reprogramming of cell metabolism. These adaptations include remodeling in glycolytic and mitochondrial metabolic fluxes, potentially altering energy substrate availability at the tissue level. This phenomenon may be highly relevant in the brain, where metabolism must be precisely regulated to maintain appropriate neuronal excitability and synaptic transmission. Direct evidence that microglia can impact on neuronal energy metabolism has been widely lacking, however. Combining molecular profiling, electrophysiology, oxygen microsensor recordings and mathematical modeling, we investigated microglia-mediated disturbances in brain energetics during neuroinflammation. Our results suggest that proinflammatory microglia showing enhanced nitric oxide release and decreased CX3CR1 expression transiently increase the tissue lactate/glucose ratio that depends on transcriptional reprogramming in microglia, not in neurons. In this condition, neuronal network activity such as gamma oscillations (30-70 Hz) can be fueled by increased ATP production in mitochondria, which is reflected by elevated oxygen consumption. During dysregulated inflammation, high energy demand and low glucose availability can be boundary conditions for neuronal metabolic fitness as revealed by kinetic modeling of single neuron energetics. Collectively, these findings indicate that metabolic flexibility protects neuronal network function against alterations in local substrate availability during moderate neuroinflammation.
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Affiliation(s)
- Bruno Chausse
- Institute of Physiology and Pathophysiology, Heidelberg University, Im Neuenheimer Feld 326, 69120, Heidelberg, Germany.
- MEDISS Doctoral Program, INF 110, Heidelberg University, 69120, Heidelberg, Germany.
| | - Nikolai Malorny
- Institute of Physiology and Pathophysiology, Heidelberg University, Im Neuenheimer Feld 326, 69120, Heidelberg, Germany
| | - Andrea Lewen
- Institute of Physiology and Pathophysiology, Heidelberg University, Im Neuenheimer Feld 326, 69120, Heidelberg, Germany
| | - Gernot Poschet
- Metabolomics Core Technology Platform, Centre for Organismal Studies, Heidelberg University, 69120, Heidelberg, Germany
| | - Nikolaus Berndt
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), 14558, Nuthetal, Germany
- Institute of Computer-Assisted Cardiovascular Medicine, Deutsches Herzzentrum der Charité (DHZC), 13353, Berlin, Germany
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117, Berlin, Germany
| | - Oliver Kann
- Institute of Physiology and Pathophysiology, Heidelberg University, Im Neuenheimer Feld 326, 69120, Heidelberg, Germany.
- Interdisciplinary Center for Neurosciences (IZN), Heidelberg University, 69120, Heidelberg, Germany.
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Fornari Laurindo L, Aparecido Dias J, Cressoni Araújo A, Torres Pomini K, Machado Galhardi C, Rucco Penteado Detregiachi C, Santos de Argollo Haber L, Donizeti Roque D, Dib Bechara M, Vialogo Marques de Castro M, de Souza Bastos Mazuqueli Pereira E, José Tofano R, Jasmin Santos German Borgo I, Maria Barbalho S. Immunological dimensions of neuroinflammation and microglial activation: exploring innovative immunomodulatory approaches to mitigate neuroinflammatory progression. Front Immunol 2024; 14:1305933. [PMID: 38259497 PMCID: PMC10800801 DOI: 10.3389/fimmu.2023.1305933] [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: 10/02/2023] [Accepted: 12/15/2023] [Indexed: 01/24/2024] Open
Abstract
The increasing life expectancy has led to a higher incidence of age-related neurodegenerative conditions. Within this framework, neuroinflammation emerges as a significant contributing factor. It involves the activation of microglia and astrocytes, leading to the release of pro-inflammatory cytokines and chemokines and the infiltration of peripheral leukocytes into the central nervous system (CNS). These instances result in neuronal damage and neurodegeneration through activated nucleotide-binding domain and leucine-rich repeat containing (NLR) family pyrin domain containing protein 3 (NLRP3) and nuclear factor kappa B (NF-kB) pathways and decreased nuclear factor erythroid 2-related factor 2 (Nrf2) activity. Due to limited effectiveness regarding the inhibition of neuroinflammatory targets using conventional drugs, there is challenging growth in the search for innovative therapies for alleviating neuroinflammation in CNS diseases or even before their onset. Our results indicate that interventions focusing on Interleukin-Driven Immunomodulation, Chemokine (CXC) Receptor Signaling and Expression, Cold Exposure, and Fibrin-Targeted strategies significantly promise to mitigate neuroinflammatory processes. These approaches demonstrate potential anti-neuroinflammatory effects, addressing conditions such as Multiple Sclerosis, Experimental autoimmune encephalomyelitis, Parkinson's Disease, and Alzheimer's Disease. While the findings are promising, immunomodulatory therapies often face limitations due to Immune-Related Adverse Events. Therefore, the conduction of randomized clinical trials in this matter is mandatory, and will pave the way for a promising future in the development of new medicines with specific therapeutic targets.
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Affiliation(s)
- Lucas Fornari Laurindo
- Department of Biochemistry and Pharmacology, School of Medicine, Faculdade de Medicina de Marília (FAMEMA), Marília, São Paulo, Brazil
- Department of Biochemistry and Pharmacology, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
| | - Jefferson Aparecido Dias
- Department of Biochemistry and Pharmacology, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
- Postgraduate Program in Structural and Functional Interactions in Rehabilitation, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
| | - Adriano Cressoni Araújo
- Department of Biochemistry and Pharmacology, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
- Postgraduate Program in Structural and Functional Interactions in Rehabilitation, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
| | - Karina Torres Pomini
- Postgraduate Program in Structural and Functional Interactions in Rehabilitation, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
- Department of Anatomy, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
| | - Cristiano Machado Galhardi
- Department of Biochemistry and Pharmacology, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
| | - Claudia Rucco Penteado Detregiachi
- Postgraduate Program in Structural and Functional Interactions in Rehabilitation, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
| | - Luíza Santos de Argollo Haber
- Department of Biochemistry and Pharmacology, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
| | - Domingos Donizeti Roque
- Department of Biochemistry and Pharmacology, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
- Department of Anatomy, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
| | - Marcelo Dib Bechara
- Department of Biochemistry and Pharmacology, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
| | - Marcela Vialogo Marques de Castro
- Postgraduate Program in Structural and Functional Interactions in Rehabilitation, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
| | - Eliana de Souza Bastos Mazuqueli Pereira
- Postgraduate Program in Structural and Functional Interactions in Rehabilitation, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
| | - Ricardo José Tofano
- Department of Biochemistry and Pharmacology, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
| | - Iris Jasmin Santos German Borgo
- Department of Biological Sciences (Anatomy), School of Dentistry of Bauru, Universidade de São Paulo (FOB-USP), Bauru, São Paulo, Brazil
| | - Sandra Maria Barbalho
- Department of Biochemistry and Pharmacology, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
- Postgraduate Program in Structural and Functional Interactions in Rehabilitation, School of Medicine, Universidade de Marília (UNIMAR), Marília, São Paulo, Brazil
- Department of Biochemistry and Nutrition, School of Food and Technology of Marília (FATEC), Marília, São Paulo, Brazil
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Gong L, Liang J, Xie L, Zhang Z, Mei Z, Zhang W. Metabolic Reprogramming in Gliocyte Post-cerebral Ischemia/ Reperfusion: From Pathophysiology to Therapeutic Potential. Curr Neuropharmacol 2024; 22:1672-1696. [PMID: 38362904 DOI: 10.2174/1570159x22666240131121032] [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: 08/21/2023] [Revised: 12/08/2023] [Accepted: 12/13/2023] [Indexed: 02/17/2024] Open
Abstract
Ischemic stroke is a leading cause of disability and death worldwide. However, the clinical efficacy of recanalization therapy as a preferred option is significantly hindered by reperfusion injury. The transformation between different phenotypes of gliocytes is closely associated with cerebral ischemia/ reperfusion injury (CI/RI). Moreover, gliocyte polarization induces metabolic reprogramming, which refers to the shift in gliocyte phenotype and the overall transformation of the metabolic network to compensate for energy demand and building block requirements during CI/RI caused by hypoxia, energy deficiency, and oxidative stress. Within microglia, the pro-inflammatory phenotype exhibits upregulated glycolysis, pentose phosphate pathway, fatty acid synthesis, and glutamine synthesis, whereas the anti-inflammatory phenotype demonstrates enhanced mitochondrial oxidative phosphorylation and fatty acid oxidation. Reactive astrocytes display increased glycolysis but impaired glycogenolysis and reduced glutamate uptake after CI/RI. There is mounting evidence suggesting that manipulation of energy metabolism homeostasis can induce microglial cells and astrocytes to switch from neurotoxic to neuroprotective phenotypes. A comprehensive understanding of underlying mechanisms and manipulation strategies targeting metabolic pathways could potentially enable gliocytes to be reprogrammed toward beneficial functions while opening new therapeutic avenues for CI/RI treatment. This review provides an overview of current insights into metabolic reprogramming mechanisms in microglia and astrocytes within the pathophysiological context of CI/RI, along with potential pharmacological targets. Herein, we emphasize the potential of metabolic reprogramming of gliocytes as a therapeutic target for CI/RI and aim to offer a novel perspective in the treatment of CI/RI.
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Affiliation(s)
- Lipeng Gong
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, College of Integrated Traditional Chinese Medicine and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
| | - Junjie Liang
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, College of Integrated Traditional Chinese Medicine and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
| | - Letian Xie
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, College of Integrated Traditional Chinese Medicine and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
| | - Zhanwei Zhang
- Department of Neurosurgery, First Affiliated Hospital of Hunan University of Traditional Chinese Medicine, Changsha, Hunan 410007, China
| | - Zhigang Mei
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, College of Integrated Traditional Chinese Medicine and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
- Third-Grade Pharmacological Laboratory on Chinese Medicine Approved by State Administration of Traditional Chinese Medicine, College of Medicine and Health Sciences, China Three Gorges University, Yichang, Hubei 443002, China
| | - Wenli Zhang
- School of Pharmacy, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
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Chen H, Guo Z, Sun Y, Dai X. The immunometabolic reprogramming of microglia in Alzheimer's disease. Neurochem Int 2023; 171:105614. [PMID: 37748710 DOI: 10.1016/j.neuint.2023.105614] [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: 07/28/2023] [Revised: 09/08/2023] [Accepted: 09/14/2023] [Indexed: 09/27/2023]
Abstract
Alzheimer's disease (AD) is an age-related neurodegenerative disorder (NDD). In the central nervous system (CNS), immune cells like microglia could reprogram intracellular metabolism to alter or exert cellular immune functions in response to environmental stimuli. In AD, microglia could be activated and differentiated into pro-inflammatory or anti-inflammatory phenotypes, and these differences in cellular phenotypes resulted in variance in cellular energy metabolism. Considering the enormous energy requirement of microglia for immune functions, the changes in mitochondria-centered energy metabolism and substrates of microglia are crucial for the cellular regulation of immune responses. Here we reviewed the mechanisms of microglial metabolic reprogramming by analyzing their flexible metabolic patterns and changes that occurred in their metabolism during the development of AD. Further, we summarized the role of drugs in modulating immunometabolic reprogramming to prevent neuroinflammation, which may shed light on a new research direction for AD treatment.
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Affiliation(s)
- Hongli Chen
- Beijing Key Laboratory of Bioactive Substances and Functional Food, College of Biochemical Engineering, Beijing Union University, Beijing, 100023, China
| | - Zichen Guo
- Beijing Key Laboratory of Bioactive Substances and Functional Food, College of Biochemical Engineering, Beijing Union University, Beijing, 100023, China
| | - Yaxuan Sun
- Beijing Key Laboratory of Bioactive Substances and Functional Food, College of Biochemical Engineering, Beijing Union University, Beijing, 100023, China
| | - Xueling Dai
- Beijing Key Laboratory of Bioactive Substances and Functional Food, College of Biochemical Engineering, Beijing Union University, Beijing, 100023, China.
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González Ibáñez F, Halvorson T, Sharma K, McKee CG, Carrier M, Picard K, Vernoux N, Bisht K, Deslauriers J, Lalowski M, Tremblay MÈ. Ketogenic diet changes microglial morphology and the hippocampal lipidomic profile differently in stress susceptible versus resistant male mice upon repeated social defeat. Brain Behav Immun 2023; 114:383-406. [PMID: 37689276 DOI: 10.1016/j.bbi.2023.09.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 08/30/2023] [Accepted: 09/06/2023] [Indexed: 09/11/2023] Open
Abstract
Psychological stress confers an increased risk for several diseases including psychiatric conditions. The susceptibility to psychological stress is modulated by various factors, many of them being modifiable lifestyle choices. The ketogenic diet (KD) has emerged as a dietary regime that offers positive outcomes on mood and health status. Psychological stress and elevated inflammation are common features of neuropsychiatric disorders such as certain types of major depressive disorder. KD has been attributed anti-inflammatory properties that could underlie its beneficial consequences on the brain and behavior. Microglia are the main drivers of inflammation in the central nervous system. They are known to respond to both dietary changes and psychological stress, notably by modifying their production of cytokines and relationships among the brain parenchyma. To assess the interactions between KD and the stress response, including effects on microglia, we examined adult male mice on control diet (CD) versus KD that underwent 10 days of repeated social defeat (RSD) or remained non-stressed (controls; CTRLs). Through a social interaction test, stressed mice were classified as susceptible (SUS) or resistant (RES) to RSD. The mouse population fed a KD tended to have a higher proportion of individuals classified as RES following RSD. Microglial morphology and ultrastructure were then analyzed in the ventral hippocampus CA1, a brain region known to present structural alterations as a response to psychological stress. Distinct changes in microglial soma and arborization linked to the KD, SUS and RES phenotypes were revealed. Ultrastructural analysis by electron microscopy showed a clear reduction of cellular stress markers in microglia from KD fed animals. Furthermore, ultrastructural analysis showed that microglial contacts with synaptic elements were reduced in the SUS compared to the RES and CTRL groups. Hippocampal lipidomic analyses lastly identified a distinct lipid profile in SUS animals compared to CTRLs. These key differences, combined with the distinct microglial responses to diet and stress, indicate that unique metabolic changes may underlie the stress susceptibility phenotypes. Altogether, our results reveal novel mechanisms by which a KD might improve the resistance to psychological stress.
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Affiliation(s)
- Fernando González Ibáñez
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada; Département de Médecine Moléculaire, Université Laval, Québec, Quebec, Canada; Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Torin Halvorson
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada; Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kaushik Sharma
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada; Département de Médecine Moléculaire, Université Laval, Québec, Quebec, Canada; Department of Chemistry, Purdue University, West Lafayette, Indiana, United States
| | - Chloe Grace McKee
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Micaël Carrier
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada; Département de Médecine Moléculaire, Université Laval, Québec, Quebec, Canada; Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Katherine Picard
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada; Département de Médecine Moléculaire, Université Laval, Québec, Quebec, Canada; Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Nathalie Vernoux
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada
| | - Kanchan Bisht
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada; Département de Médecine Moléculaire, Université Laval, Québec, Quebec, Canada; Department of Chemistry, Purdue University, West Lafayette, Indiana, United States
| | | | - Maciej Lalowski
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland; Biochemistry/Developmental Biology and HiLIFE, Meilahti Clinical Proteomics Core Facility, University of Helsinki, Finland
| | - Marie-Ève Tremblay
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada; Département de Médecine Moléculaire, Université Laval, Québec, Quebec, Canada; Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada; Neurology and Neurosurgery Department, McGill University, Montréal, Quebec, Canada; Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia, Canada; Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, British Columbia, Canada.
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9
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Strogulski NR, Portela LV, Polster BM, Loane DJ. Fundamental Neurochemistry Review: Microglial immunometabolism in traumatic brain injury. J Neurochem 2023; 167:129-153. [PMID: 37759406 PMCID: PMC10655864 DOI: 10.1111/jnc.15959] [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: 07/05/2023] [Revised: 08/28/2023] [Accepted: 08/29/2023] [Indexed: 09/29/2023]
Abstract
Traumatic brain injury (TBI) is a devastating neurological disorder caused by a physical impact to the brain that promotes diffuse damage and chronic neurodegeneration. Key mechanisms believed to support secondary brain injury include mitochondrial dysfunction and chronic neuroinflammation. Microglia and brain-infiltrating macrophages are responsible for neuroinflammatory cytokine and reactive oxygen species (ROS) production after TBI. Their production is associated with loss of homeostatic microglial functions such as immunosurveillance, phagocytosis, and immune resolution. Beyond providing energy support, mitochondrial metabolic pathways reprogram the pro- and anti-inflammatory machinery in immune cells, providing a critical immunometabolic axis capable of regulating immunologic response to noxious stimuli. In the brain, the capacity to adapt to different environmental stimuli derives, in part, from microglia's ability to recognize and respond to changes in extracellular and intracellular metabolite levels. This capacity is met by an equally plastic metabolism, capable of altering immune function. Microglial pro-inflammatory activation is associated with decreased mitochondrial respiration, whereas anti-inflammatory microglial polarization is supported by increased oxidative metabolism. These metabolic adaptations contribute to neuroimmune responses, placing mitochondria as a central regulator of post-traumatic neuroinflammation. Although it is established that profound neurometabolic changes occur following TBI, key questions related to metabolic shifts in microglia remain unresolved. These include (a) the nature of microglial mitochondrial dysfunction after TBI, (b) the hierarchical positions of different metabolic pathways such as glycolysis, pentose phosphate pathway, glutaminolysis, and lipid oxidation during secondary injury and recovery, and (c) how immunometabolism alters microglial phenotypes, culminating in chronic non-resolving neuroinflammation. In this basic neurochemistry review article, we describe the contributions of immunometabolism to TBI, detail primary evidence of mitochondrial dysfunction and metabolic impairments in microglia and macrophages, discuss how major metabolic pathways contribute to post-traumatic neuroinflammation, and set out future directions toward advancing immunometabolic phenotyping in TBI.
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Affiliation(s)
- Nathan R. Strogulski
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| | - Luis V. Portela
- Neurotrauma and Biomarkers Laboratory, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Brian M. Polster
- Department of Anesthesiology and Shock, Trauma and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - David J. Loane
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
- Department of Anesthesiology and Shock, Trauma and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
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10
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González Ibáñez F, Halvorson T, Sharma K, McKee C, Carrier M, Picard K, Vernoux N, Bisht K, Deslauriers J, Lalowski M, Tremblay MÈ. Ketogenic diet alters microglial morphology and changes the hippocampal lipidomic profile distinctively in stress susceptible versus resistant male mice upon repeated social defeat. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.28.555135. [PMID: 37693370 PMCID: PMC10491121 DOI: 10.1101/2023.08.28.555135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Psychological stress confers an increased risk for several diseases including psychiatric conditions. The susceptibility to psychological stress is modulated by various factors, many of them being modifiable lifestyle choices. The ketogenic diet (KD) has emerged as a dietary regime that offers positive outcomes on mood and health status. Psychological stress and elevated inflammation are common features of neuropsychiatric disorders such as certain types of major depressive disorder. KD has been attributed anti-inflammatory properties that could underlie its beneficial consequences on the brain and behavior. Microglia are the main drivers of inflammation in the central nervous system. They are known to respond to both dietary changes and psychological stress, notably by modifying their production of cytokines and relationships among the brain parenchyma. To assess the interactions between KD and the stress response, including effects on microglia, we examined adult male mice on control diet (CD) versus KD that underwent 10 days of repeated social defeat (RSD) or remained non-stressed (controls; CTRLs). Through a social interaction test, stressed mice were classified as susceptible (SUS) or resistant (RES) to RSD. The mouse population fed a KD tended to have a higher proportion of individuals classified as RES following RSD. Microglial morphology and ultrastructure were then analyzed in the ventral hippocampus CA1, a brain region known to present structural alterations as a response to psychological stress. Distinct changes in microglial soma and arborization linked to the KD, SUS and RES phenotypes were revealed. Ultrastructural analysis by electron microscopy showed a clear reduction of cellular stress markers in microglia from KD fed animals. Furthermore, ultrastructural analysis showed that microglial contacts with synaptic elements were reduced in the SUS compared to the RES and CTRL groups. Hippocampal lipidomic analyses lastly identified a distinct lipid profile in SUS animals compared to CTRLs. These key differences, combined with the distinct microglial responses to diet and stress, indicate that unique metabolic changes may underlie the stress susceptibility phenotypes. Altogether, our results reveal novel mechanisms by which a KD might improve the resistance to psychological stress.
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Affiliation(s)
- Fernando González Ibáñez
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Torin Halvorson
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Department of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Kaushik Sharma
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
- Department of Chemistry, Purdue University, West Lafayette, IN, United States of America
| | - Chloe McKee
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Micaël Carrier
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Katherine Picard
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Nathalie Vernoux
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
| | - Kanchan Bisht
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
- Department of Chemistry, Purdue University, West Lafayette, IN, United States of America
| | | | - Maciej Lalowski
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
- Biochemistry/Developmental Biology, Meilahti Clinical Proteomics Core Facility, University of Helsinki, Finland
| | - Marie-Ève Tremblay
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Neurology and Neurosurgery Department, McGill University, Montréal, QC, Canada
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, BC, Canada
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11
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Xiao X, Hu H, Zhong Y, Chen Y, Tang K, Pan Z, Huang J, Yang X, Wang Q, Gao Y. Microglia Sirt6 modulates the transcriptional activity of NRF2 to ameliorate high-fat diet-induced obesity. Mol Med 2023; 29:108. [PMID: 37582706 PMCID: PMC10428617 DOI: 10.1186/s10020-023-00676-9] [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: 01/31/2023] [Accepted: 05/31/2023] [Indexed: 08/17/2023] Open
Abstract
BACKGROUND Microglia play a pivotal role in neuroinflammation, while obesity triggers hypothalamic microglia activation and inflammation. Sirt6 is an important regulator of energy metabolism in many peripheral tissues and hypothalamic anorexic neurons. However, the exact mechanism for microglia Sirt6 in controlling high-fat diet-induced obesity remain unknown. METHODS Microglia Sirt6 expression levels under various nutritional conditions were measured in the hypothalamus of mice. Also, microglia Sirt6-deficient mice were provided various diets to monitor metabolic changes and hypothalamic inflammatory response. Besides, RNA-seq and Co-IP of microglia with Sirt6 alterations were conducted to further investigate the detailed mechanism by which Sirt6 modulated microglia activity. RESULTS We found that Sirt6 was downregulated in hypothalamic microglia in mice given a high-fat diet (HFD). Additionally, knockout of microglia Sirt6 exacerbated high-fat diet-induced hypothalamic microglial activation and inflammation. As a result, mice were more prone to obesity, exhibiting a decrease in energy expenditure, impaired glucose tolerance, insulin and leptin resistance, and increased food intake. In vitro, Sirt6 overexpression in BV2 cells displayed protective effects against oleic acid and palmitic acid treatment-derived inflammatory response. Mechanically, Sirt6 deacetylated and stabilised NRF2 to increase the expression of anti-oxidative genes and defend against reactive oxygen species overload. Pharmacological inhibition of NRF2 eliminated the beneficial modulating effects of Sirt6 on microglial activity. CONCLUSION Collectively, our results revealed that microglial Sirt6 was a primary contributor of microglial activation in the central regulation of obesity. Thus, microglial Sirt6 may be an important therapeutic target for obesity.
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Affiliation(s)
- Xiaoxia Xiao
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Huiling Hu
- Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510289, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510289, China
| | - Yadi Zhong
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Yingjian Chen
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Kaijia Tang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Zhisen Pan
- First Affiliated Hospital, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Jiawen Huang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Xiaoying Yang
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogen Biology and Immunology, Xuzhou Medical University, Xuzhou, 221004, Jiangsu, China.
| | - Qi Wang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China.
| | - Yong Gao
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China.
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12
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Müller MA, Zweig N, Spengler B, Weinert M, Heiles S. Lipid Signatures and Inter-Cellular Heterogeneity of Naı̈ve and Lipopolysaccharide-Stimulated Human Microglia-like Cells. Anal Chem 2023; 95:11672-11679. [PMID: 37506282 DOI: 10.1021/acs.analchem.3c01533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2023]
Abstract
Microglia are non-neuronal cells, which reside in the central nervous system and are known to play an important role in health and disease. We investigated the lipidomic phenotypes of human naı̈ve and stimulated microglia-like cells by atmospheric-pressure scanning microprobe matrix-assisted laser desorption/ionization mass spectrometry imaging (AP-SMALDI MSI). With lateral resolutions between 5 and 1.5 μm pixel size, we were able to chart lipid compositions of individual cells, enabling differentiation of cell lines and stimulation conditions. This allowed us to reveal local lipid heterogeneities in naı̈ve and lipopolysaccharide (LPS)-stimulated cells. We were able to identify individual cells with elevated triglyceride (TG) levels and could show that the number of these TG-enriched cells increased with LPS stimulation as a hallmark for a proinflammatory phenotype. Additionally, the observed local abundance alterations of specific phosphatidylinositols (PIs) indicate a cell specific regulation of the PI metabolism.
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Affiliation(s)
- Max A Müller
- Institute of Inorganic and Analytical Chemistry, Analytical Chemistry, Justus Liebig University Giessen, 35392 Giessen, Germany
| | - Norman Zweig
- Institute of Inorganic and Analytical Chemistry, Analytical Chemistry, Justus Liebig University Giessen, 35392 Giessen, Germany
| | - Bernhard Spengler
- Institute of Inorganic and Analytical Chemistry, Analytical Chemistry, Justus Liebig University Giessen, 35392 Giessen, Germany
| | - Maria Weinert
- Department of Brain Sciences, Imperial College London, Hammersmith Hospital, W12 0NN London, U.K
| | - Sven Heiles
- Institute of Inorganic and Analytical Chemistry, Analytical Chemistry, Justus Liebig University Giessen, 35392 Giessen, Germany
- Leibniz-Institut für Analytische Wissenschaften─ISAS─e.V., 44139 Dortmund, Germany
- Faculty of Chemistry, University of Duisburg-Essen, 45141 Essen, Germany
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13
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Yamamoto S, Masuda T. Lipid in microglial biology - from material to mediator. Inflamm Regen 2023; 43:38. [PMID: 37460930 PMCID: PMC10351166 DOI: 10.1186/s41232-023-00289-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 07/06/2023] [Indexed: 07/20/2023] Open
Abstract
Microglia are resident macrophages in the central nervous system (CNS) that play various roles during brain development and in the pathogenesis of CNS diseases. Recently, reprogramming of cellular energetic metabolism in microglia has drawn attention as a crucial mechanism for diversification of microglial functionality. Lipids are highly diverse materials and crucial components of cell membranes in every cell. Accumulating evidence has shown that lipid and its metabolism are tightly involved in microglial biology. In this review, we summarize the current knowledge about microglial lipid metabolism in health and disease.
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Affiliation(s)
- Shota Yamamoto
- Division of Molecular Neuroimmunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, 812-8582, Japan.
| | - Takahiro Masuda
- Division of Molecular Neuroimmunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, 812-8582, Japan.
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14
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Wieder N, Fried JC, Kim C, Sidhom EH, Brown MR, Marshall JL, Arevalo C, Dvela-Levitt M, Kost-Alimova M, Sieber J, Gabriel KR, Pacheco J, Clish C, Abbasi HS, Singh S, Rutter JC, Therrien M, Yoon H, Lai ZW, Baublis A, Subramanian R, Devkota R, Small J, Sreekanth V, Han M, Lim D, Carpenter AE, Flannick J, Finucane H, Haigis MC, Claussnitzer M, Sheu E, Stevens B, Wagner BK, Choudhary A, Shaw JL, Pablo JL, Greka A. FALCON systematically interrogates free fatty acid biology and identifies a novel mediator of lipotoxicity. Cell Metab 2023; 35:887-905.e11. [PMID: 37075753 PMCID: PMC10257950 DOI: 10.1016/j.cmet.2023.03.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 02/21/2023] [Accepted: 03/27/2023] [Indexed: 04/21/2023]
Abstract
Cellular exposure to free fatty acids (FFAs) is implicated in the pathogenesis of obesity-associated diseases. However, there are no scalable approaches to comprehensively assess the diverse FFAs circulating in human plasma. Furthermore, assessing how FFA-mediated processes interact with genetic risk for disease remains elusive. Here, we report the design and implementation of fatty acid library for comprehensive ontologies (FALCON), an unbiased, scalable, and multimodal interrogation of 61 structurally diverse FFAs. We identified a subset of lipotoxic monounsaturated fatty acids associated with decreased membrane fluidity. Furthermore, we prioritized genes that reflect the combined effects of harmful FFA exposure and genetic risk for type 2 diabetes (T2D). We found that c-MAF-inducing protein (CMIP) protects cells from FFA exposure by modulating Akt signaling. In sum, FALCON empowers the study of fundamental FFA biology and offers an integrative approach to identify much needed targets for diverse diseases associated with disordered FFA metabolism.
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Affiliation(s)
- Nicolas Wieder
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA; Department of Neurology with Experimental Neurology and Berlin Institute of Health, Charité, 10117 Berlin, Germany
| | - Juliana Coraor Fried
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Choah Kim
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Eriene-Heidi Sidhom
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Matthew R Brown
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Carlos Arevalo
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Moran Dvela-Levitt
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA; The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | | | - Jonas Sieber
- Department of Endocrinology, Metabolism and Cardiovascular Systems, University of Fribourg, Fribourg, Switzerland
| | | | - Julian Pacheco
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Clary Clish
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Shantanu Singh
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Justine C Rutter
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Harvard Medical School, Boston, MA 02115, USA
| | | | - Haejin Yoon
- Department of Cell Biology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Ludwig Center for Cancer Research at Harvard, Boston, MA 02115, USA
| | - Zon Weng Lai
- Harvard Chan Advanced Multiomics Platform, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Aaron Baublis
- Harvard Chan Advanced Multiomics Platform, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Renuka Subramanian
- Laboratory for Surgical and Metabolic Research, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Ranjan Devkota
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jonnell Small
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Harvard Medical School, Boston, MA 02115, USA; Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Vedagopuram Sreekanth
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Myeonghoon Han
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Donghyun Lim
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Jason Flannick
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Harvard Medical School, Boston, MA 02115, USA; Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA 02115, USA
| | - Hilary Finucane
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Analytic and Translational Genetics Unit, Mass General Hospital, Boston, MA 02114, USA
| | - Marcia C Haigis
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Cell Biology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Ludwig Center for Cancer Research at Harvard, Boston, MA 02115, USA
| | - Melina Claussnitzer
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Harvard Medical School, Boston, MA 02115, USA; Metabolism Program, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Eric Sheu
- Laboratory for Surgical and Metabolic Research, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Beth Stevens
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Harvard Medical School, Boston, MA 02115, USA; Boston Children's Hospital, F.M. Kirby Neurobiology Center, Boston, MA 02115, USA; Howard Hughes Medical Institute, Boston, MA 02115, USA
| | - Bridget K Wagner
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Amit Choudhary
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Harvard Medical School, Boston, MA 02115, USA; Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Jillian L Shaw
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Anna Greka
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA.
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15
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Chen L, Zhang Q, Meng Y, Zhao T, Mu C, Fu C, Deng C, Feng J, Du S, Liu W, Geng G, Ma K, Cheng H, Liu Q, Luo Q, Zhang J, Du Z, Cao L, Wang H, Liu Y, Lin J, Chen G, Liu L, Lam SM, Shui G, Zhu Y, Chen Q. Saturated fatty acids increase LPI to reduce FUNDC1 dimerization and stability and mitochondrial function. EMBO Rep 2023; 24:e54731. [PMID: 36847607 PMCID: PMC10074135 DOI: 10.15252/embr.202254731] [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: 01/29/2022] [Revised: 01/19/2023] [Accepted: 02/02/2023] [Indexed: 03/01/2023] Open
Abstract
Ectopic lipid deposition and mitochondrial dysfunction are common etiologies of obesity and metabolic disorders. Excessive dietary uptake of saturated fatty acids (SFAs) causes mitochondrial dysfunction and metabolic disorders, while unsaturated fatty acids (UFAs) counterbalance these detrimental effects. It remains elusive how SFAs and UFAs differentially signal toward mitochondria for mitochondrial performance. We report here that saturated dietary fatty acids such as palmitic acid (PA), but not unsaturated oleic acid (OA), increase lysophosphatidylinositol (LPI) production to impact on the stability of the mitophagy receptor FUNDC1 and on mitochondrial quality. Mechanistically, PA shifts FUNDC1 from dimer to monomer via enhanced production of LPI. Monomeric FUNDC1 shows increased acetylation at K104 due to dissociation of HDAC3 and increased interaction with Tip60. Acetylated FUNDC1 can be further ubiquitinated by MARCH5 for proteasomal degradation. Conversely, OA antagonizes PA-induced accumulation of LPI, and FUNDC1 monomerization and degradation. A fructose-, palmitate-, and cholesterol-enriched (FPC) diet also affects FUNDC1 dimerization and promotes its degradation in a non-alcoholic steatohepatitis (NASH) mouse model. We thus uncover a signaling pathway that orchestrates lipid metabolism with mitochondrial quality.
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Affiliation(s)
- Linbo Chen
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Qianping Zhang
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Yuanyuan Meng
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Tian Zhao
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Chenglong Mu
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Changying Fu
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Caijuan Deng
- College of Pharmacy, Frontiers Science Center for Cell ResponsesNankai UniversityTianjinChina
| | - Jianyu Feng
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Siling Du
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Wei Liu
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Guangfeng Geng
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Kaili Ma
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Hongcheng Cheng
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Qiangqiang Liu
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Qian Luo
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Jiaojiao Zhang
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Zhanqiang Du
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Lin Cao
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Hui Wang
- Cancer InstituteXuzhou Medical UniversityXuzhouChina
| | - Yong Liu
- Cancer InstituteXuzhou Medical UniversityXuzhouChina
| | - Jianping Lin
- College of Pharmacy, Frontiers Science Center for Cell ResponsesNankai UniversityTianjinChina
| | - Guo Chen
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Lei Liu
- State Key Laboratory of Membrane Biology, Institute of ZoologyChinese Academy of SciencesBeijingChina
| | - Sin Man Lam
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijingChina
- LipidAll Technologies Company LimitedChangzhouChina
| | - Guanghou Shui
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijingChina
| | - Yushan Zhu
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
| | - Quan Chen
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, Tianjin Key Laboratory of Protein Science, College of Life SciencesNankai UniversityTianjinChina
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16
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Galkina OV, Vetrovoy OV, Krasovskaya IE, Eschenko ND. Role of Lipids in Regulation of Neuroglial Interactions. BIOCHEMISTRY. BIOKHIMIIA 2023; 88:337-352. [PMID: 37076281 DOI: 10.1134/s0006297923030045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 01/24/2023] [Accepted: 01/26/2023] [Indexed: 03/28/2023]
Abstract
Lipids comprise an extremely heterogeneous group of compounds that perform a wide variety of biological functions. Traditional view of lipids as important structural components of the cell and compounds playing a trophic role is currently being supplemented by information on the possible participation of lipids in signaling, not only intracellular, but also intercellular. The review article discusses current data on the role of lipids and their metabolites formed in glial cells (astrocytes, oligodendrocytes, microglia) in communication of these cells with neurons. In addition to metabolic transformations of lipids in each type of glial cells, special attention is paid to the lipid signal molecules (phosphatidic acid, arachidonic acid and its metabolites, cholesterol, etc.) and the possibility of their participation in realization of synaptic plasticity, as well as in other possible mechanisms associated with neuroplasticity. All these new data can significantly expand our knowledge about the regulatory functions of lipids in neuroglial relationships.
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Affiliation(s)
- Olga V Galkina
- Biochemistry Department, Faculty of Biology, Saint-Petersburg State University, St. Petersburg, 199034, Russia.
| | - Oleg V Vetrovoy
- Biochemistry Department, Faculty of Biology, Saint-Petersburg State University, St. Petersburg, 199034, Russia
- Pavlov Institute of Physiology, Russian Academy of Sciences, St. Petersburg, 199034, Russia
| | - Irina E Krasovskaya
- Biochemistry Department, Faculty of Biology, Saint-Petersburg State University, St. Petersburg, 199034, Russia
| | - Nataliya D Eschenko
- Biochemistry Department, Faculty of Biology, Saint-Petersburg State University, St. Petersburg, 199034, Russia
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17
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Benarroch E. What Is the Role of Microglial Metabolism in Inflammation and Neurodegeneration? Neurology 2022; 99:99-105. [PMID: 35851556 DOI: 10.1212/wnl.0000000000200920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 05/16/2022] [Indexed: 11/15/2022] Open
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18
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LPS-induced lipid alterations in microglia revealed by MALDI mass spectrometry-based cell fingerprinting in neuroinflammation studies. Sci Rep 2022; 12:2908. [PMID: 35190595 PMCID: PMC8861089 DOI: 10.1038/s41598-022-06894-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 02/03/2022] [Indexed: 12/17/2022] Open
Abstract
Pathological microglia activation can promote neuroinflammation in many neurodegenerative diseases, and it has therefore emerged as a potential therapeutic target. Increasing evidence suggests alterations in lipid metabolism as modulators and indicators in microglia activation and its effector functions. Yet, how lipid dynamics in activated microglia is affected by inflammatory stimuli demands additional investigation to allow development of more effective therapies. Here, we report an extensive matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) whole cell fingerprinting workflow to investigate inflammation-associated lipid patterns in SIM-A9 microglial cells. By combining a platform of three synergistic MALDI MS technologies we could detect substantial differences in lipid profiles of lipopolysaccharide (LPS)- stimulated and unstimulated microglia-like cells leading to the identification of 21 potential inflammation-associated lipid markers. LPS-induced lipids in SIM-A9 microglial cells include phosphatidylcholines, lysophosphatidylcholines (LysoPC), sphingolipids, diacylglycerols and triacylglycerols. Moreover, MALDI MS-based cell lipid fingerprinting of LPS-stimulated SIM-A9 microglial cells pre-treated with the non-selective histone deacetylase inhibitor suberoylanilide hydroxamic acid revealed specific modulation of LPS-induced-glycerolipids and LysoPC(18:0) with a significant reduction of microglial inflammation response. Our study introduces MALDI MS as a complementary technology for fast and label-free investigation of stimulus-dependent changes in lipid patterns and their modulation by pharmaceutical agents.
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19
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Urso C, Zhou H. Palmitic Acid Lipotoxicity in Microglia Cells Is Ameliorated by Unsaturated Fatty Acids. Int J Mol Sci 2021; 22:ijms22169093. [PMID: 34445796 PMCID: PMC8396597 DOI: 10.3390/ijms22169093] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 08/16/2021] [Accepted: 08/20/2021] [Indexed: 01/04/2023] Open
Abstract
Obesity and metabolic syndrome are associated with cognitive decline and dementia. Palmitic acid (PA) is increased in the cerebrospinal fluid of obese patients with cognitive impairment. This study was therefore designed to examine fatty acid (FA) lipotoxicity in BV2 microglia cells. We found that PA induced time- and dose-dependent decrease in cell viability and increase in cell death without affecting the cell cycle profile and that PA lipotoxicity did not depend on cell surface free fatty acid receptors but rather on FA uptake. Treatment with sulfosuccinimidyl oleate (SSO), an irreversible inhibitor of fatty acid translocase CD36, significantly inhibited FA uptake in BSA- and PA-treated cells and blocked PA-induced decrease in cell viability. Inhibition of ER stress or treatment with N-acetylcysteine was not able to rescue PA lipotoxicity. Our study also showed that unsaturated fatty acids (UFAs), such as linoleic acid (LA), oleic acid (OA), α-linolenic acid (ALA), and docosahexaenoic acid (DHA), were not lipotoxic but instead protected microglia against PA-induced decrease in cell viability. Co-treatment of PA with LA, OA, and DHA significantly inhibited FA uptake in PA-treated cells. All UFAs tested induced the incorporation of FAs into and the amount of neutral lipids, while PA did not significantly affect the amount of neutral lipids compared with BSA control.
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20
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Ralhan I, Chang CL, Lippincott-Schwartz J, Ioannou MS. Lipid droplets in the nervous system. J Cell Biol 2021; 220:e202102136. [PMID: 34152362 PMCID: PMC8222944 DOI: 10.1083/jcb.202102136] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 05/31/2021] [Accepted: 06/01/2021] [Indexed: 01/20/2023] Open
Abstract
Lipid droplets are dynamic intracellular lipid storage organelles that respond to the physiological state of cells. In addition to controlling cell metabolism, they play a protective role for many cellular stressors, including oxidative stress. Despite prior descriptions of lipid droplets appearing in the brain as early as a century ago, only recently has the role of lipid droplets in cells found in the brain begun to be understood. Lipid droplet functions have now been described for cells of the nervous system in the context of development, aging, and an increasing number of neuropathologies. Here, we review the basic mechanisms of lipid droplet formation, turnover, and function and discuss how these mechanisms enable lipid droplets to function in different cell types of the nervous system under healthy and pathological conditions.
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Affiliation(s)
- Isha Ralhan
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
- Group on Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada
| | - Chi-Lun Chang
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA
| | | | - Maria S. Ioannou
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
- Group on Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
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21
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Kakimoto PA, Serna JDC, de Miranda Ramos V, Zorzano A, Kowaltowski AJ. Increased glycolysis is an early consequence of palmitate lipotoxicity mediated by redox signaling. Redox Biol 2021; 45:102026. [PMID: 34102573 PMCID: PMC8187254 DOI: 10.1016/j.redox.2021.102026] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Revised: 05/14/2021] [Accepted: 05/24/2021] [Indexed: 10/27/2022] Open
Abstract
Exposure to toxic levels of fatty acids (lipotoxicity) leads to cell damage and death and is involved in the pathogenesis of the metabolic syndrome. Since the metabolic consequences of lipotoxicity are still poorly understood, we studied the bioenergetic effects of the saturated fatty acid palmitate, quantifying changes in mitochondrial morphology, real-time oxygen consumption, ATP production sources, and extracellular acidification in hepatoma cells. Surprisingly, glycolysis was enhanced by the presence of palmitate as soon as 1 h after stimulus, while oxygen consumption and oxidative phosphorylation were unchanged, despite overt mitochondrial fragmentation. Palmitate only induced mitochondrial fragmentation if glucose and glutamine were available, while glycolytic enhancement did not require glutamine, showing it is independent of mitochondrial morphological changes. Redox state was altered by palmitate, as indicated by NAD(P)H quantification. Furthermore, the mitochondrial antioxidant mitoquinone, or a selective inhibitor of complex I electron leakage (S1QEL) further enhanced palmitate-induced glycolysis. Our results demonstrate that palmitate overload and lipotoxicity involves an unexpected and early increase in glycolytic flux, while, surprisingly, no changes in oxidative phosphorylation are observed. Interestingly, enhanced glycolysis involves signaling by mitochondrially-generated oxidants, uncovering a novel regulatory mechanism for this pathway.
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Affiliation(s)
- Pamela A Kakimoto
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil.
| | - Julian David C Serna
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Vitor de Miranda Ramos
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Antonio Zorzano
- Institute for Research in Biomedicine (IRB Barcelona), Departament de Bioquímica I Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Barcelona, Spain
| | - Alicia J Kowaltowski
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil.
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22
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Changes in mitochondrial morphology modulate LPS-induced loss of calcium homeostasis in BV-2 microglial cells. J Bioenerg Biomembr 2021; 53:109-118. [PMID: 33585958 DOI: 10.1007/s10863-021-09878-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 02/05/2021] [Indexed: 12/18/2022]
Abstract
Microglial activation involves both fragmentation of the mitochondrial network and changes in cellular Ca2+ homeostasis, but possible modifications in mitochondrial calcium uptake have never been described in this context. Here we report that activated microglial BV-2 cells have impaired mitochondrial calcium uptake, including lower calcium retention capacity and calcium uptake rates. These changes were not dependent on altered expression of the mitochondrial calcium uniporter. Respiratory capacity and the inner membrane potential, key determinants of mitochondrial calcium uptake, are both decreased in activated microglial BV-2 cells. Modified mitochondrial calcium uptake correlates with impaired cellular calcium signaling, including reduced ER calcium stores, and decreased replenishment by store operated calcium entry (SOCE). Induction of mitochondrial fragmentation through Mfn2 knockdown in control cells mimicked this effect, while inhibiting LPS-induced mitochondrial fragmentation by a dominant negative form of Drp1 prevented it. Overall, our results show that mitochondrial fragmentation induced by LPS promotes altered Ca2+ homeostasis in microglial cells, a new aspect of microglial activation that could be a key feature in the inflammatory role of these cells.
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23
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Yang S, Qin C, Hu ZW, Zhou LQ, Yu HH, Chen M, Bosco DB, Wang W, Wu LJ, Tian DS. Microglia reprogram metabolic profiles for phenotype and function changes in central nervous system. Neurobiol Dis 2021; 152:105290. [PMID: 33556540 DOI: 10.1016/j.nbd.2021.105290] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 12/31/2020] [Accepted: 02/03/2021] [Indexed: 12/13/2022] Open
Abstract
In response to various types of environmental and cellular stress, microglia rapidly activate and exhibit either pro- or anti-inflammatory phenotypes to maintain tissue homeostasis. Activation of microglia can result in changes in morphology, phagocytosis capacity, and secretion of cytokines. Furthermore, microglial activation also induces changes to cellular energy demand, which is dependent on the metabolism of various metabolic substrates including glucose, fatty acids, and amino acids. Accumulating evidence demonstrates metabolic reprogramming acts as a key driver of microglial immune response. For instance, microglia in pro-inflammatory states preferentially use glycolysis for energy production, whereas, cells in anti-inflammatory states are mainly powered by oxidative phosphorylation and fatty acid oxidation. In this review, we summarize recent findings regarding microglial metabolic pathways under physiological and pathological circumtances. We will then discuss how metabolic reprogramming can orchestrate microglial response to a variety of central nervous system pathologies. Finally, we highlight how manipulating metabolic pathways can reprogram microglia towards beneficial functions, and illustrate the therapeutic potential for inflammation-related neurological diseases.
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Affiliation(s)
- Sheng Yang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Chuan Qin
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Zi-Wei Hu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Luo-Qi Zhou
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Hai-Han Yu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Man Chen
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Dale B Bosco
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, United States of America
| | - Wei Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Long-Jun Wu
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, United States of America.
| | - Dai-Shi Tian
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
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24
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Loving BA, Tang M, Neal MC, Gorkhali S, Murphy R, Eckel RH, Bruce KD. Lipoprotein Lipase Regulates Microglial Lipid Droplet Accumulation. Cells 2021; 10:cells10020198. [PMID: 33498265 PMCID: PMC7909280 DOI: 10.3390/cells10020198] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 01/12/2021] [Accepted: 01/15/2021] [Indexed: 12/18/2022] Open
Abstract
Microglia become increasingly dysfunctional with aging and contribute to the onset of neurodegenerative disease (NDs) through defective phagocytosis, attenuated cholesterol efflux, and excessive secretion of pro-inflammatory cytokines. Dysfunctional microglia also accumulate lipid droplets (LDs); however, the mechanism underlying increased LD load is unknown. We have previously shown that microglia lacking lipoprotein lipase (LPL KD) are polarized to a pro-inflammatory state and have impaired lipid uptake and reduced fatty acid oxidation (FAO). Here, we also show that LPL KD microglia show excessive accumulation of LD-like structures. Moreover, LPL KD microglia display a pro-inflammatory lipidomic profile, increased cholesterol ester (CE) content, and reduced cholesterol efflux at baseline. We also show reduced expression of genes within the canonical cholesterol efflux pathway. Importantly, PPAR agonists (rosiglitazone and bezafibrate) rescued the LD-associated phenotype in LPL KD microglia. These data suggest that microglial-LPL is associated with lipid uptake, which may drive PPAR signaling and cholesterol efflux to prevent inflammatory lipid distribution and LD accumulation. Moreover, PPAR agonists can reverse LD accumulation, and therefore may be beneficial in aging and in the treatment of NDs.
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Affiliation(s)
- Bailey A. Loving
- Department of Radiation Oncology, Oakland University William Beaumont School of Medicine, Royal Oak, MI 48309, USA;
| | - Maoping Tang
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA; (M.T.); (M.C.N.); (S.G.); (R.H.E.)
| | - Mikaela C. Neal
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA; (M.T.); (M.C.N.); (S.G.); (R.H.E.)
| | - Sachi Gorkhali
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA; (M.T.); (M.C.N.); (S.G.); (R.H.E.)
| | - Robert Murphy
- Department of Pharmacology, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA;
| | - Robert H. Eckel
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA; (M.T.); (M.C.N.); (S.G.); (R.H.E.)
| | - Kimberley D. Bruce
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA; (M.T.); (M.C.N.); (S.G.); (R.H.E.)
- Correspondence:
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25
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Deng W, Mandeville E, Terasaki Y, Li W, Holder J, Chuang AT, Ning M, Arai K, Lo EH, Xing C. Transcriptomic characterization of microglia activation in a rat model of ischemic stroke. J Cereb Blood Flow Metab 2020; 40:S34-S48. [PMID: 33208001 PMCID: PMC7687036 DOI: 10.1177/0271678x20932870] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Microglia are key regulators of inflammatory response after stroke and brain injury. To better understand activation of microglia as well as their phenotypic diversity after ischemic stroke, we profiled the transcriptome of microglia after 75 min transient focal cerebral ischemia in 3-month- and 12-month-old male spontaneously hypertensive rats. Microglia were isolated from the brains by FACS sorting on days 3 and 14 after cerebral ischemia. GeneChip Rat 1.0ST microarray was used to profile the whole transcriptome of sorted microglia. We identified an evolving and complex pattern of activation from 3 to 14 days after stroke onset. M2-like patterns were extensively and persistently upregulated over time. M1-like patterns were only mildly upregulated, mostly at day 14. Younger 3-month-old brains showed a larger microglial response in both pro- and anti-inflammatory pathways, compared to older 12-month-old brains. Importantly, our data revealed that after stroke, most microglia are activated towards a wide spectrum of novel polarization states beyond the standard M1/M2 dichotomy, especially in pathways related to TLR2 and dietary fatty acid signaling. Finally, classes of transcription factors that might potentially regulate microglial activation were identified. These findings should provide a comprehensive database for dissecting microglial mechanisms and pursuing neuroinflammation targets for acute ischemic stroke.
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Affiliation(s)
- Wenjun Deng
- Neuroprotection Research Laboratories, Departments of Radiology and Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA.,Clinical Proteomics Research Center, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Emiri Mandeville
- Neuroprotection Research Laboratories, Departments of Radiology and Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Yasukazu Terasaki
- Neuroprotection Research Laboratories, Departments of Radiology and Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Wenlu Li
- Neuroprotection Research Laboratories, Departments of Radiology and Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | | | | | - Mingming Ning
- Clinical Proteomics Research Center, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Ken Arai
- Neuroprotection Research Laboratories, Departments of Radiology and Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Eng H Lo
- Neuroprotection Research Laboratories, Departments of Radiology and Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA.,Clinical Proteomics Research Center, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Changhong Xing
- Neuroprotection Research Laboratories, Departments of Radiology and Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA.,Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA
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26
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Gil-de-Gómez L, Balgoma D, Montero O. Lipidomic-Based Advances in Diagnosis and Modulation of Immune Response to Cancer. Metabolites 2020; 10:metabo10080332. [PMID: 32824009 PMCID: PMC7465074 DOI: 10.3390/metabo10080332] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/12/2020] [Accepted: 08/12/2020] [Indexed: 02/07/2023] Open
Abstract
While immunotherapies for diverse types of cancer are effective in many cases, relapse is still a lingering problem. Like tumor cells, activated immune cells have an anabolic metabolic profile, relying on glycolysis and the increased uptake and synthesis of fatty acids. In contrast, immature antigen-presenting cells, as well as anergic and exhausted T-cells have a catabolic metabolic profile that uses oxidative phosphorylation to provide energy for cellular processes. One goal for enhancing current immunotherapies is to identify metabolic pathways supporting the immune response to tumor antigens. A robust cell expansion and an active modulation via immune checkpoints and cytokine release are required for effective immunity. Lipids, as one of the main components of the cell membrane, are the key regulators of cell signaling and proliferation. Therefore, lipid metabolism reprogramming may impact proliferation and generate dysfunctional immune cells promoting tumor growth. Based on lipid-driven signatures, the discrimination between responsiveness and tolerance to tumor cells will support the development of accurate biomarkers and the identification of potential therapeutic targets. These findings may improve existing immunotherapies and ultimately prevent immune escape in patients for whom existing treatments have failed.
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Affiliation(s)
- Luis Gil-de-Gómez
- Center for Childhood Cancer Research, Children’s Hospital of Philadelphia, Colket Translational Research Center, 3501 Civic Center Blvd, PA 19104, USA
- Correspondence:
| | - David Balgoma
- Analytical Pharmaceutical Chemistry, Department of Medicinal Chemistry, Uppsala University, Husarg. 3, 75123 Uppsala, Sweden;
| | - Olimpio Montero
- Spanish National Research Council (CSIC), Boecillo’s Technological Park Bureau, Av. Francisco Vallés 8, 47151 Boecillo, Spain;
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27
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Dikmen HO, Hemmerich M, Lewen A, Hollnagel JO, Chausse B, Kann O. GM-CSF induces noninflammatory proliferation of microglia and disturbs electrical neuronal network rhythms in situ. J Neuroinflammation 2020; 17:235. [PMID: 32782006 PMCID: PMC7418331 DOI: 10.1186/s12974-020-01903-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 07/16/2020] [Indexed: 12/19/2022] Open
Abstract
Background The granulocyte-macrophage colony-stimulating factor (GM-CSF) (or CSF-2) is involved in myeloid cell growth and differentiation, and, possibly, a major mediator of inflammation in body tissues. The role of GM-CSF in the activation of microglia (CNS resident macrophages) and the consequent impacts on neuronal survival, excitability, and synaptic transmission are widely unknown, however. Here, we focused on electrical neuronal network rhythms in the gamma frequency band (30–70 Hz). Gamma oscillations are fundamental to higher brain functions, such as perception, attention, and memory, and they are exquisitely sensitive to metabolic and oxidative stress. Methods We explored the effects of chronic GM-CSF exposure (72 h) on microglia in male rat organotypic hippocampal slice cultures (in situ), i.e., postnatal cortex tissue lacking leukocyte invasion (adaptive immunity). We applied extracellular electrophysiological recordings of local field potential, immunohistochemistry, design-based stereology, biochemical analysis, and pharmacological ablation of microglia. Results GM-CSF triggered substantial proliferation of microglia (microgliosis). By contrast, the release of proinflammatory cytokines (IL-6, TNF-α) and nitric oxide, the hippocampal cytoarchitecture as well as the morphology of parvalbumin-positive inhibitory interneurons were unaffected. Notably, GM-CSF induced concentration-dependent, long-lasting disturbances of gamma oscillations, such as slowing (beta frequency band) and neural burst firing (hyperexcitability), which were not mimicked by the T lymphocyte cytokine IL-17. These disturbances were attenuated by depletion of the microglial cell population with liposome-encapsulated clodronate. In contrast to priming with the cytokine IFN-γ (type II interferon), GM-CSF did not cause inflammatory neurodegeneration when paired with the TLR4 ligand LPS. Conclusions GM-CSF has a unique role in the activation of microglia, including the potential to induce neuronal network dysfunction. These immunomodulatory properties might contribute to cognitive impairment and/or epileptic seizure development in disease featuring elevated GM-CSF levels, blood-brain barrier leakage, and/or T cell infiltration.
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Affiliation(s)
- Hasan Onur Dikmen
- Institute of Physiology and Pathophysiology, University of Heidelberg, Im Neuenheimer Feld 326, 69120, Heidelberg, Germany
| | - Marc Hemmerich
- Institute of Physiology and Pathophysiology, University of Heidelberg, Im Neuenheimer Feld 326, 69120, Heidelberg, Germany
| | - Andrea Lewen
- Institute of Physiology and Pathophysiology, University of Heidelberg, Im Neuenheimer Feld 326, 69120, Heidelberg, Germany
| | - Jan-Oliver Hollnagel
- Institute of Physiology and Pathophysiology, University of Heidelberg, Im Neuenheimer Feld 326, 69120, Heidelberg, Germany
| | - Bruno Chausse
- Institute of Physiology and Pathophysiology, University of Heidelberg, Im Neuenheimer Feld 326, 69120, Heidelberg, Germany.
| | - Oliver Kann
- Institute of Physiology and Pathophysiology, University of Heidelberg, Im Neuenheimer Feld 326, 69120, Heidelberg, Germany.,Interdisciplinary Center for Neurosciences (IZN), University of Heidelberg, Heidelberg, Germany
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28
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Rodríguez-Gómez JA, Kavanagh E, Engskog-Vlachos P, Engskog MK, Herrera AJ, Espinosa-Oliva AM, Joseph B, Hajji N, Venero JL, Burguillos MA. Microglia: Agents of the CNS Pro-Inflammatory Response. Cells 2020; 9:E1717. [PMID: 32709045 PMCID: PMC7407646 DOI: 10.3390/cells9071717] [Citation(s) in RCA: 150] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 07/14/2020] [Accepted: 07/15/2020] [Indexed: 12/21/2022] Open
Abstract
The pro-inflammatory immune response driven by microglia is a key contributor to the pathogenesis of several neurodegenerative diseases. Though the research of microglia spans over a century, the last two decades have increased our understanding exponentially. Here, we discuss the phenotypic transformation from homeostatic microglia towards reactive microglia, initiated by specific ligand binding to pattern recognition receptors including toll-like receptor-4 (TLR4) or triggering receptors expressed on myeloid cells-2 (TREM2), as well as pro-inflammatory signaling pathways triggered such as the caspase-mediated immune response. Additionally, new research disciplines such as epigenetics and immunometabolism have provided us with a more holistic view of how changes in DNA methylation, microRNAs, and the metabolome may influence the pro-inflammatory response. This review aimed to discuss our current knowledge of pro-inflammatory microglia from different angles, including recent research highlights such as the role of exosomes in spreading neuroinflammation and emerging techniques in microglia research including positron emission tomography (PET) scanning and the use of human microglia generated from induced pluripotent stem cells (iPSCs). Finally, we also discuss current thoughts on the impact of pro-inflammatory microglia in neurodegenerative diseases.
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Affiliation(s)
- José A. Rodríguez-Gómez
- Institute of Biomedicine of Seville (IBIS)-Hospital Universitario Virgen del Rocío/CSIC/University of Seville, 41012 Seville, Spain; (J.A.R.-G.); (A.J.H.); (A.M.E.-O.); (J.L.V.)
- Department of Medical Physiology and Biophysics, Faculty of Medicine, University of Seville, 41009 Sevilla, Spain
| | - Edel Kavanagh
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Seville, 41012 Seville, Spain;
| | - Pinelopi Engskog-Vlachos
- Institute of Environmental Medicine, Toxicology Unit, Karolinska Institute, 17177 Stockholm, Sweden; (P.E.-V.); (B.J.)
| | - Mikael K.R. Engskog
- Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Uppsala University, 751 23 Uppsala, Sweden;
| | - Antonio J. Herrera
- Institute of Biomedicine of Seville (IBIS)-Hospital Universitario Virgen del Rocío/CSIC/University of Seville, 41012 Seville, Spain; (J.A.R.-G.); (A.J.H.); (A.M.E.-O.); (J.L.V.)
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Seville, 41012 Seville, Spain;
| | - Ana M. Espinosa-Oliva
- Institute of Biomedicine of Seville (IBIS)-Hospital Universitario Virgen del Rocío/CSIC/University of Seville, 41012 Seville, Spain; (J.A.R.-G.); (A.J.H.); (A.M.E.-O.); (J.L.V.)
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Seville, 41012 Seville, Spain;
| | - Bertrand Joseph
- Institute of Environmental Medicine, Toxicology Unit, Karolinska Institute, 17177 Stockholm, Sweden; (P.E.-V.); (B.J.)
| | - Nabil Hajji
- Division of Brain Sciences, The John Fulcher Molecular Neuro-Oncology Laboratory, Imperial College London, London W12 ONN, UK;
| | - José L. Venero
- Institute of Biomedicine of Seville (IBIS)-Hospital Universitario Virgen del Rocío/CSIC/University of Seville, 41012 Seville, Spain; (J.A.R.-G.); (A.J.H.); (A.M.E.-O.); (J.L.V.)
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Seville, 41012 Seville, Spain;
| | - Miguel A. Burguillos
- Institute of Biomedicine of Seville (IBIS)-Hospital Universitario Virgen del Rocío/CSIC/University of Seville, 41012 Seville, Spain; (J.A.R.-G.); (A.J.H.); (A.M.E.-O.); (J.L.V.)
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Seville, 41012 Seville, Spain;
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Loving BA, Bruce KD. Lipid and Lipoprotein Metabolism in Microglia. Front Physiol 2020; 11:393. [PMID: 32411016 PMCID: PMC7198855 DOI: 10.3389/fphys.2020.00393] [Citation(s) in RCA: 104] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 04/02/2020] [Indexed: 12/25/2022] Open
Abstract
Microglia, once viewed as static bystanders with limited homeostatic functions, are now considered key players in the development of neuroinflammatory and neurodegenerative diseases. Microglial activation is a salient feature of neuroinflammation involving a dynamic process that generates multitudinous microglial phenotypes that can respond to a variety of situational cues in the central nervous system. Recently, a flurry of single cell RNA-sequencing studies have defined microglial phenotypes in unprecedented detail, and have highlighted robust changes in the expression of genes involved in lipid and lipoprotein metabolism. Increased expression of genes such as Apolipoprotein E (ApoE), Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) and Lipoprotein Lipase (LPL) in microglia during development, damage, and disease, suggest that increased lipid metabolism is needed to fuel protective cellular functions such as phagocytosis. This review describes our current understanding of lipid and lipoprotein metabolism in microglia, and highlights microglial lipid metabolism as a modifiable target for the treatment of neurodegenerative diseases such as Alzheimer's disease and multiple sclerosis.
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Affiliation(s)
- Bailey A. Loving
- School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO, United States
| | - Kimberley D. Bruce
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Anschutz Medical Campus, Aurora, CO, United States
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