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Cruciani-Guglielmacci C, Le Stunff H, Magnan C. Brain lipid sensing and the neural control of energy balance. Biochimie 2024; 223:159-165. [PMID: 38825062 DOI: 10.1016/j.biochi.2024.05.020] [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: 04/11/2024] [Revised: 05/23/2024] [Accepted: 05/25/2024] [Indexed: 06/04/2024]
Abstract
The central nervous system continuously detects circulating concentrations of lipids such as fatty acids and troglycerides. Once information has been detected, the central nervous system can in turn participate in the control of energy balance and blood sugar levels and in particular regulate the secretion and action of insulin. Neurons capable of detecting circulating lipid variations are located in the hypothalamus and in other regions such as the nucleus accumbens, the striatum or the hippocampus. An excess of lipids will have deleterious effects and may induce central lipotoxicity, in particular following local production of ceramides and the appearance of neuroinflammation which may lead to metabolic diseases such as obesity and type 2 diabetes.
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Affiliation(s)
| | - Hervé Le Stunff
- Paris-Saclay Institute of Neuroscience, CNRS UMR 9197, Université Paris-Sud, University Paris Saclay, Orsay, France
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2
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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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3
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Lee TH, Cota D, Quarta C. Yin-Yang control of energy balance by lipids in the hypothalamus: The endocannabinoids vs bile acids case. Biochimie 2024; 223:188-195. [PMID: 35863558 DOI: 10.1016/j.biochi.2022.07.006] [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: 05/23/2022] [Revised: 06/22/2022] [Accepted: 07/12/2022] [Indexed: 11/02/2022]
Abstract
Obesity is a chronic and debilitating disorder that originates from alterations in energy-sensing brain circuits controlling body weight gain and food intake. The dysregulated syntheses and actions of lipid mediators in the hypothalamus induce weight gain and overfeeding, but the molecular and cellular underpinnings of these alterations remain elusive. In response to changes in the nutritional status, different lipid sensing pathways in the hypothalamus direct body energy needs in a Yin-Yang model. Endocannabinoids orchestrate the crosstalk between hypothalamic circuits and the sympathetic nervous system to promote food intake and energy accumulation during fasting, whereas bile acids act on the same top-down axis to reduce energy intake and possibly storage after the meal. In obesity, the bioavailability and downstream cellular actions of endocannabinoids and bile acids are altered in hypothalamic neurons involved in body weight and metabolic control. Thus, the onset and progression of this disease might result from an imbalance in hypothalamic sensing of multiple lipid signals, which are possibly integrated by common molecular nodes. In this viewpoint, we discuss a possible model that explains how bile acids and endocannabinoids may exert their effects on energy balance regulation via interconnected mechanisms at the level of the hypothalamic neuronal circuits. Therefore, we propose a new conceptual framework for understanding and treating central mechanisms of maladaptive lipid action in obesity.
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Affiliation(s)
- Thomas H Lee
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, F-3300, Bordeaux, France
| | - Daniela Cota
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, F-3300, Bordeaux, France
| | - Carmelo Quarta
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, F-3300, Bordeaux, France.
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4
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Loganathan N, Lieu CV, Belsham DD. Immortalization and Characterization of GFAP-expressing Glial Cells from the Adult Mouse Hypothalamus, Cortex, and Brain Stem. Neuroscience 2024; 551:43-54. [PMID: 38788830 DOI: 10.1016/j.neuroscience.2024.05.022] [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: 03/25/2024] [Revised: 04/23/2024] [Accepted: 05/19/2024] [Indexed: 05/26/2024]
Abstract
The generation of astrocyte cell lines from the hypothalamus is key to study glial involvement in hypothalamic physiology, including energy homeostasis. As such, we immortalized astrocytes from the hypothalamus of an adult male CD-1 mouse using SV40 T-antigen to generate the mHypoA-Ast1 cell line. A comparative approach was taken with two other murine GFAP-expressing cell lines that were also generated in this study: a mixed glial cell line from the cortex (mCortA-G1) and an oligodendrocyte cell line from the brainstem (mBstA-Olig1), as well as an established microglial cell line (IMG). mHypoA-Ast1 cells express GFAP, alongside other astrocytic markers such as Aldh1l1, Aqp4, Glt1 and S100b, and express low levels of microglial, ependymal and oligodendrocyte markers. 100 ng/mL lipopolysaccharide (LPS) elevated mRNA levels of Il6, Il1b, Tnfα and Cxcl5 in mHypoA-Ast1 cells after 4 h, while 50 μM palmitate increased Il6 and Chop mRNA, demonstrating the ability of these cells to respond to inflammatory and nutrient signals. Interestingly, co-culture of mHypoA-Ast1 cells with mHypoE-N46 hypothalamic neuronal cells prevented the palmitate-mediated increase in orexigenic neuropeptide Agrp mRNA in mHypoE-N46 cells, suggesting that this cell line can alter neuronal responses to nutrients. In conclusion, we report mHypoA-Ast1 cells representing a functional astrocyte cell line from the adult mouse brain that can be used to study the complex interactions of hypothalamic cells, as well as dysregulation that may occur in disease states, providing a key tool for neuroendocrine research.
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Affiliation(s)
- Neruja Loganathan
- Departments of Physiology, University of Toronto, Toronto, ON, Canada
| | - Calvin V Lieu
- Departments of Physiology, University of Toronto, Toronto, ON, Canada
| | - Denise D Belsham
- Departments of Physiology, University of Toronto, Toronto, ON, Canada; Medicine, University of Toronto, Toronto, ON, Canada.
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5
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Frago LM, Gómez-Romero A, Collado-Pérez R, Argente J, Chowen JA. Synergism Between Hypothalamic Astrocytes and Neurons in Metabolic Control. Physiology (Bethesda) 2024; 39:0. [PMID: 38530221 DOI: 10.1152/physiol.00009.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 03/05/2024] [Accepted: 03/22/2024] [Indexed: 03/27/2024] Open
Abstract
Astrocytes are no longer considered as passive support cells. In the hypothalamus, these glial cells actively participate in the control of appetite, energy expenditure, and the processes leading to obesity and its secondary complications. Here we briefly review studies supporting this conclusion and the advances made in understanding the underlying mechanisms.
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Affiliation(s)
- Laura M Frago
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, Madrid, Spain
- Department of Pediatrics, Faculty of Medicine, Universidad Autónoma de Madrid, Madrid, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Madrid, Spain
| | - Alfonso Gómez-Romero
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, Madrid, Spain
- Department of Pediatrics, Faculty of Medicine, Universidad Autónoma de Madrid, Madrid, Spain
| | - Roberto Collado-Pérez
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, Madrid, Spain
- Department of Pediatrics, Faculty of Medicine, Universidad Autónoma de Madrid, Madrid, Spain
| | - Jesús Argente
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, Madrid, Spain
- Department of Pediatrics, Faculty of Medicine, Universidad Autónoma de Madrid, Madrid, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Madrid, Spain
- IMDEA Food Institute, Campus of International Excellence, Universidad Autónoma de Madrid, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Julie A Chowen
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, Madrid, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Madrid, Spain
- IMDEA Food Institute, Campus of International Excellence, Universidad Autónoma de Madrid, Consejo Superior de Investigaciones Científicas, Madrid, Spain
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6
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Wilkerson JL, Tatum SM, Holland WL, Summers SA. Ceramides are fuel gauges on the drive to cardiometabolic disease. Physiol Rev 2024; 104:1061-1119. [PMID: 38300524 DOI: 10.1152/physrev.00008.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 01/23/2024] [Accepted: 01/25/2024] [Indexed: 02/02/2024] Open
Abstract
Ceramides are signals of fatty acid excess that accumulate when a cell's energetic needs have been met and its nutrient storage has reached capacity. As these sphingolipids accrue, they alter the metabolism and survival of cells throughout the body including in the heart, liver, blood vessels, skeletal muscle, brain, and kidney. These ceramide actions elicit the tissue dysfunction that underlies cardiometabolic diseases such as diabetes, coronary artery disease, metabolic-associated steatohepatitis, and heart failure. Here, we review the biosynthesis and degradation pathways that maintain ceramide levels in normal physiology and discuss how the loss of ceramide homeostasis drives cardiometabolic pathologies. We highlight signaling nodes that sense small changes in ceramides and in turn reprogram cellular metabolism and stimulate apoptosis. Finally, we evaluate the emerging therapeutic utility of these unique lipids as biomarkers that forecast disease risk and as targets of ceramide-lowering interventions that ameliorate disease.
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Affiliation(s)
- Joseph L Wilkerson
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
| | - Sean M Tatum
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
| | - William L Holland
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
| | - Scott A Summers
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
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7
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Li Z, Jiang YY, Long C, Peng X, Tao J, Pu Y, Yue R. Bridging metabolic syndrome and cognitive dysfunction: role of astrocytes. Front Endocrinol (Lausanne) 2024; 15:1393253. [PMID: 38800473 PMCID: PMC11116704 DOI: 10.3389/fendo.2024.1393253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 04/25/2024] [Indexed: 05/29/2024] Open
Abstract
Metabolic syndrome (MetS) and cognitive dysfunction pose significant challenges to global health and the economy. Systemic inflammation, endocrine disruption, and autoregulatory impairment drive neurodegeneration and microcirculatory damage in MetS. Due to their unique anatomy and function, astrocytes sense and integrate multiple metabolic signals, including peripheral endocrine hormones and nutrients. Astrocytes and synapses engage in a complex dialogue of energetic and immunological interactions. Astrocytes act as a bridge between MetS and cognitive dysfunction, undergoing diverse activation in response to metabolic dysfunction. This article summarizes the alterations in astrocyte phenotypic characteristics across multiple pathological factors in MetS. It also discusses the clinical value of astrocytes as a critical pathologic diagnostic marker and potential therapeutic target for MetS-associated cognitive dysfunction.
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Affiliation(s)
- Zihan Li
- Department of Endocrinology, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
- Clinical Medical School, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ya-yi Jiang
- Department of Endocrinology, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
- Clinical Medical School, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Caiyi Long
- Department of Endocrinology, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
- Clinical Medical School, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Xi Peng
- Department of Endocrinology, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
- Clinical Medical School, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Jiajing Tao
- Department of Endocrinology, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
- Clinical Medical School, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Yueheng Pu
- Department of Endocrinology, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
- Clinical Medical School, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Rensong Yue
- Department of Endocrinology, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
- Clinical Medical School, Chengdu University of Traditional Chinese Medicine, Chengdu, China
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8
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Zhang X, Chen C, Liu Y. Navigating the metabolic maze: anomalies in fatty acid and cholesterol processes in Alzheimer's astrocytes. Alzheimers Res Ther 2024; 16:63. [PMID: 38521950 PMCID: PMC10960454 DOI: 10.1186/s13195-024-01430-x] [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: 11/27/2023] [Accepted: 03/13/2024] [Indexed: 03/25/2024]
Abstract
Alzheimer's disease (AD) is the most common cause of dementia, and its underlying mechanisms have been a subject of great interest. The mainstream theory of AD pathology suggests that the disease is primarily associated with tau protein and amyloid-beta (Aβ). However, an increasing body of research has revealed that abnormalities in lipid metabolism may be an important event throughout the pathophysiology of AD. Astrocytes, as important members of the lipid metabolism network in the brain, play a significant role in this event. The study of abnormal lipid metabolism in astrocytes provides a new perspective for understanding the pathogenesis of AD. This review focuses on the abnormal metabolism of fatty acids (FAs) and cholesterol in astrocytes in AD, and discusses it from three perspectives: lipid uptake, intracellular breakdown or synthesis metabolism, and efflux transport. We found that, despite the accumulation of their own fatty acids, astrocytes cannot efficiently uptake fatty acids from neurons, leading to fatty acid accumulation within neurons and resulting in lipotoxicity. In terms of cholesterol metabolism, astrocytes exhibit a decrease in endogenous synthesis due to the accumulation of exogenous cholesterol. Through a thorough investigation of these metabolic abnormalities, we can provide new insights for future therapeutic strategies by literature review to navigate this complex metabolic maze and bring hope to patients with Alzheimer's disease.
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Affiliation(s)
- Xiaoyu Zhang
- Department of Neurosurgery, Institute of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Chuanying Chen
- Department of Neurosurgery, Institute of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
- School of Traditional Chinese Medicine, Southern Medical University, 1838 North Guangzhou Avenue, Guangzhou, Guangdong, 510515, People's Republic of China
| | - Yi Liu
- Department of Neurosurgery, Institute of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China.
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Huang HX, Inglese P, Tang J, Yagoubi R, Correia GDS, Horneffer-van der Sluis VM, Camuzeaux S, Wu V, Kopanitsa MV, Willumsen N, Jackson JS, Barron AM, Saito T, Saido TC, Gentlemen S, Takats Z, Matthews PM. Mass spectrometry imaging highlights dynamic patterns of lipid co-expression with Aβ plaques in mouse and human brains. J Neurochem 2024. [PMID: 38372586 DOI: 10.1111/jnc.16042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 11/13/2023] [Accepted: 12/06/2023] [Indexed: 02/20/2024]
Abstract
Lipids play crucial roles in the susceptibility and brain cellular responses to Alzheimer's disease (AD) and are increasingly considered potential soluble biomarkers in cerebrospinal fluid (CSF) and plasma. To delineate the pathological correlations of distinct lipid species, we conducted a comprehensive characterization of both spatially localized and global differences in brain lipid composition in AppNL-G-F mice with spatial and bulk mass spectrometry lipidomic profiling, using human amyloid-expressing (h-Aβ) and WT mouse brains controls. We observed age-dependent increases in lysophospholipids, bis(monoacylglycerol) phosphates, and phosphatidylglycerols around Aβ plaques in AppNL-G-F mice. Immunohistology-based co-localization identified associations between focal pro-inflammatory lipids, glial activation, and autophagic flux disruption. Likewise, in human donors with varying Braak stages, similar studies of cortical sections revealed co-expression of lysophospholipids and ceramides around Aβ plaques in AD (Braak stage V/VI) but not in earlier Braak stage controls. Our findings in mice provide evidence of temporally and spatially heterogeneous differences in lipid composition as local and global Aβ-related pathologies evolve. Observing similar lipidomic changes associated with pathological Aβ plaques in human AD tissue provides a foundation for understanding differences in CSF lipids with reported clinical stage or disease severity.
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Affiliation(s)
- Helen Xuexia Huang
- Section of Bioanalytical Chemistry, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
- UK Dementia Research Institute at Imperial College London, Imperial College London, London, UK
| | - Paolo Inglese
- Section of Bioanalytical Chemistry, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
- National Phenome Centre, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Jiabin Tang
- Department of Brain Sciences, Imperial College London, London, UK
| | - Riad Yagoubi
- Section of Bioanalytical Chemistry, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
- UK Dementia Research Institute at Imperial College London, Imperial College London, London, UK
| | - Gonçalo D S Correia
- Section of Bioanalytical Chemistry, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
- National Phenome Centre, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | | | - Stephane Camuzeaux
- National Phenome Centre, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Vincen Wu
- Section of Bioanalytical Chemistry, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Maksym V Kopanitsa
- UK Dementia Research Institute at Imperial College London, Imperial College London, London, UK
| | - Nanet Willumsen
- UK Dementia Research Institute at Imperial College London, Imperial College London, London, UK
- Department of Brain Sciences, Imperial College London, London, UK
| | - Johanna S Jackson
- UK Dementia Research Institute at Imperial College London, Imperial College London, London, UK
- Department of Brain Sciences, Imperial College London, London, UK
| | - Anna M Barron
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Takashi Saito
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
- Department of Neurocognitive Science, Institute of Brain Science, Nagoya City University, Graduate School of Medical Sciences, Nagoya, Aichi, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
- Department of Neurocognitive Science, Institute of Brain Science, Nagoya City University, Graduate School of Medical Sciences, Nagoya, Aichi, Japan
| | - Steve Gentlemen
- Department of Brain Sciences, Imperial College London, London, UK
| | - Zoltan Takats
- Section of Bioanalytical Chemistry, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Paul M Matthews
- UK Dementia Research Institute at Imperial College London, Imperial College London, London, UK
- Department of Brain Sciences, Imperial College London, London, UK
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10
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Jaraíz-Rodríguez M, Del Prado L, Balsa E. Metabolic remodeling in astrocytes: Paving the path to brain tumor development. Neurobiol Dis 2023; 188:106327. [PMID: 37839712 DOI: 10.1016/j.nbd.2023.106327] [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: 06/28/2023] [Revised: 10/11/2023] [Accepted: 10/12/2023] [Indexed: 10/17/2023] Open
Abstract
The brain is a highly metabolic organ, composed of multiple cell classes, that controls crucial functions of the body. Although neurons have traditionally been the main protagonist, astrocytes have gained significant attention over the last decade. In this regard, astrocytes are a type of glial cells that have recently emerged as critical regulators of central nervous system (CNS) function and play a significant role in maintaining brain energy metabolism. However, in certain scenarios, astrocyte behavior can go awry, which poses a significant threat to brain integrity and function. This is definitively the case for mutations that turn normal astrocytes and astrocytic precursors into gliomas, an aggressive type of brain tumor. In addition, healthy astrocytes can interact with tumor cells, becoming part of the tumor microenvironment and influencing disease progression. In this review, we discuss the recent evidence suggesting that disturbed metabolism in astrocytes can contribute to the development and progression of fatal human diseases such as cancer. Emphasis is placed on detailing the molecular bases and metabolic pathways of this disease and highlighting unique metabolic vulnerabilities that can potentially be exploited to develop successful therapeutic opportunities.
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Affiliation(s)
- Myriam Jaraíz-Rodríguez
- Centro de Biología Molecular Severo Ochoa (CBMSO), Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain
| | - Lucia Del Prado
- Centro de Biología Molecular Severo Ochoa (CBMSO), Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain
| | - Eduardo Balsa
- Centro de Biología Molecular Severo Ochoa (CBMSO), Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain; Instituto Universitario de Biología Molecular - IUBM (Universidad Autónoma de Madrid), Madrid, Spain.
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11
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Bouyakdan K, Manceau R, Robb JL, Rodaros D, Fulton S, Alquier T. Role of astroglial ACBP in energy metabolism flexibility and feeding responses to metabolic challenges in male mice. J Neuroendocrinol 2022; 34:e13218. [PMID: 36471907 DOI: 10.1111/jne.13218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 10/26/2022] [Accepted: 11/10/2022] [Indexed: 11/19/2022]
Abstract
Acyl-CoA binding protein (ACBP), also known as diazepam binding inhibitor (DBI), has recently emerged as a hypothalamic and brainstem gliopeptide regulating energy balance. Previous work has shown that the ACBP-derived octadecaneuropeptide exerts strong anorectic action via proopiomelanocortin (POMC) neuron activation and the melanocortin-4 receptor. Importantly, targeted ACBP loss-of-function in astrocytes promotes hyperphagia and diet-induced obesity while its overexpression in arcuate astrocytes reduces feeding and body weight. Despite this knowledge, the role of astroglial ACBP in adaptive feeding and metabolic responses to acute metabolic challenges has not been investigated. Using different paradigms, we found that ACBP deletion in glial fibrillary acidic protein (GFAP)-positive astrocytes does not affect weight loss when obese male mice are transitioned from a high fat diet to a chow diet, nor metabolic parameters in mice fed with a normal chow diet (e.g., energy expenditure, body temperature) during fasting, cold exposure and at thermoneutrality. In contrast, astroglial ACBP deletion impairs meal pattern and feeding responses during refeeding after a fast and during cold exposure, thereby showing that ACBP is required to stimulate feeding in states of increased energy demand. These findings challenge the general view that astroglial ACBP exerts anorectic effects and suggest that regulation of feeding by ACBP is dependent on metabolic status.
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Affiliation(s)
- Khalil Bouyakdan
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine and Neurosciences and Nutrition, Université de Montréal, Montréal, Quebec, Canada
| | - Romane Manceau
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine and Neurosciences and Nutrition, Université de Montréal, Montréal, Quebec, Canada
| | - Josephine L Robb
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine and Neurosciences and Nutrition, Université de Montréal, Montréal, Quebec, Canada
| | - Demetra Rodaros
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine and Neurosciences and Nutrition, Université de Montréal, Montréal, Quebec, Canada
| | - Stephanie Fulton
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine and Neurosciences and Nutrition, Université de Montréal, Montréal, Quebec, Canada
| | - Thierry Alquier
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine and Neurosciences and Nutrition, Université de Montréal, Montréal, Quebec, Canada
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12
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Leng L, Yuan Z, Pan R, Su X, Wang H, Xue J, Zhuang K, Gao J, Chen Z, Lin H, Xie W, Li H, Chen Z, Ren K, Zhang X, Wang W, Jin ZB, Wu S, Wang X, Yuan Z, Xu H, Chow HM, Zhang J. Microglial hexokinase 2 deficiency increases ATP generation through lipid metabolism leading to β-amyloid clearance. Nat Metab 2022; 4:1287-1305. [PMID: 36203054 DOI: 10.1038/s42255-022-00643-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 08/18/2022] [Indexed: 01/20/2023]
Abstract
Microglial cells consume adenosine triphosphate (ATP) during phagocytosis to clear neurotoxic β-amyloid in Alzheimer's disease (AD). However, the contribution of energy metabolism to microglial function in AD remains unclear. Here, we demonstrate that hexokinase 2 (HK2) is elevated in microglia from an AD mouse model (5xFAD) and AD patients. Genetic deletion or pharmacological inhibition of HK2 significantly promotes microglial phagocytosis, lowers the amyloid plaque burden and attenuates cognitive impairment in male AD mice. Notably, the ATP level is dramatically increased in HK2-deficient or inactive microglia, which can be attributed to a marked upregulation in lipoprotein lipase (LPL) expression and subsequent increase in lipid metabolism. We further show that two downstream metabolites of HK2, glucose-6-phosphate and fructose-6-phosphate, can reverse HK2-deficiency-induced upregulation of LPL, thus supporting ATP production and microglial phagocytosis. Our findings uncover a crucial role for HK2 in phagocytosis through regulation of microglial energy metabolism, suggesting a potential therapeutic strategy for AD by targeting HK2.
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Affiliation(s)
- Lige Leng
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, China.
| | - Ziqi Yuan
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, China
| | - Ruiyuan Pan
- The Brain Science Center, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Xiao Su
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, China
| | - Han Wang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, China
| | - Jin Xue
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, China
| | - Kai Zhuang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, China
| | - Ju Gao
- Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
| | - Zhenlei Chen
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, China
| | - Hui Lin
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, China
| | - Wenting Xie
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, China
| | - Huifang Li
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, China
| | - Zhenyi Chen
- Department of Anesthesiology, First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
| | - Keke Ren
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medcial University, Xi'an, Shaanxi, China
| | - Xiao Zhang
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, China
| | - Wenting Wang
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medcial University, Xi'an, Shaanxi, China
| | - Zi-Bing Jin
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, China
| | - Shengxi Wu
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medcial University, Xi'an, Shaanxi, China
| | - Xinglong Wang
- Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
| | - Zengqiang Yuan
- The Brain Science Center, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Huaxi Xu
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, China
| | - Hei-Man Chow
- School of Life Sciences, The Chinese University of Hong Kong, Sha Tin, Hong Kong
| | - Jie Zhang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, China.
- Department of Anesthesiology, First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China.
- Institute of Neuroscience, Fujian Medical University, Fuzhou, China.
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13
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Abstract
Anorexia is a loss of appetite or an inability to eat and is often associated with eating disorders. However, animal anorexia is physiologically regulated as a part of the life cycle; for instance, during hibernation, migration or incubation. Anorexia nervosa (AN), on the other hand, is a common eating disorder among adolescent females that experience an intense fear of gaining weight due to body image distortion that results in voluntary avoidance of food intake and, thus, severe weight loss. It has been shown that the neurobiology of feeding extends beyond the hypothalamus. The prefrontal cortex (PFC) is involved in food choice and body image perception, both relevant in AN. However, little is known about the neurobiology of AN, and the lack of effective treatments justifies the use of animal models. Glial cells, the dominant population of nerve cells in the central nervous system, are key in maintaining brain homeostasis. Accordingly, recent studies suggest that glial function may be compromised by anorexia. In this review, we summarize recent findings about anorexia and glial cells.
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14
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Lutomska LM, Miok V, Krahmer N, González García I, Gruber T, Le Thuc O, Murat CD, Legutko B, Sterr M, Saher G, Lickert H, Müller TD, Ussar S, Tschöp MH, Lutter D, García-Cáceres C. Diet triggers specific responses of hypothalamic astrocytes in time and region dependent manner. Glia 2022; 70:2062-2078. [PMID: 35802021 DOI: 10.1002/glia.24237] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 06/15/2022] [Accepted: 06/23/2022] [Indexed: 12/14/2022]
Abstract
Hypothalamic astrocytes are particularly affected by energy-dense food consumption. How the anatomical location of these glial cells and their spatial molecular distribution in the arcuate nucleus of the hypothalamus (ARC) determine the cellular response to a high caloric diet remains unclear. In this study, we investigated their distinctive molecular responses following exposure to a high-fat high-sugar (HFHS) diet, specifically in the ARC. Using RNA sequencing and proteomics, we showed that astrocytes have a distinct transcriptomic and proteomic profile dependent on their anatomical location, with a major proteomic reprogramming in hypothalamic astrocytes. By ARC single-cell sequencing, we observed that a HFHS diet dictates time- and cell- specific transcriptomic responses, revealing that astrocytes have the most distinct regulatory pattern compared to other cell types. Lastly, we topographically and molecularly characterized astrocytes expressing glial fibrillary acidic protein and/or aldehyde dehydrogenase 1 family member L1 in the ARC, of which the abundance was significantly increased, as well as the alteration in their spatial and molecular profiles, with a HFHS diet. Together, our results provide a detailed multi-omics view on the spatial and temporal changes of astrocytes particularly in the ARC during different time points of adaptation to a high calorie diet.
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Affiliation(s)
- Luiza Maria Lutomska
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Viktorian Miok
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Natalie Krahmer
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Ismael González García
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Tim Gruber
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Ophélia Le Thuc
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Cahuê Db Murat
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Beata Legutko
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Michael Sterr
- German Center for Diabetes Research (DZD), Neuherberg, Germany.,Institute of Diabetes and Regeneration Research, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,Technical University of Munich (TUM), Munich, Germany
| | - Gesine Saher
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Heiko Lickert
- German Center for Diabetes Research (DZD), Neuherberg, Germany.,Institute of Diabetes and Regeneration Research, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,Technical University of Munich (TUM), Munich, Germany
| | - Timo D Müller
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany.,Department of Pharmacology and Experimental Therapy, Institute of Experimental and Clinical Pharmacology and Toxicology, Eberhard Karls University Hospitals and Clinics, Tübingen, Germany
| | - Siegfried Ussar
- German Center for Diabetes Research (DZD), Neuherberg, Germany.,Technical University of Munich (TUM), Munich, Germany.,RG Adipocytes and Metabolism, Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Center Munich, Neuherberg, Germany
| | - Matthias H Tschöp
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany.,Technical University of Munich (TUM), Munich, Germany
| | - Dominik Lutter
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Cristina García-Cáceres
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany.,Medizinische Klinik and Poliklinik IV, Klinikum der Universität, Ludwig-Maximilians-Universität München, Munich, Germany
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15
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Contribution of specific ceramides to obesity-associated metabolic diseases. Cell Mol Life Sci 2022; 79:395. [PMID: 35789435 PMCID: PMC9252958 DOI: 10.1007/s00018-022-04401-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 05/20/2022] [Accepted: 05/26/2022] [Indexed: 12/04/2022]
Abstract
Ceramides are a heterogeneous group of bioactive membrane sphingolipids that play specialized regulatory roles in cellular metabolism depending on their characteristic fatty acyl chain lengths and subcellular distribution. As obesity progresses, certain ceramide molecular species accumulate in metabolic tissues and cause cell-type-specific lipotoxic reactions that disrupt metabolic homeostasis and lead to the development of cardiometabolic diseases. Several mechanisms for ceramide action have been inferred from studies in vitro, but only recently have we begun to better understand the acyl chain length specificity of ceramide-mediated signaling in the context of physiology and disease in vivo. New discoveries show that specific ceramides affect various metabolic pathways and that global or tissue-specific reduction in selected ceramide pools in obese rodents is sufficient to improve metabolic health. Here, we review the tissue-specific regulation and functions of ceramides in obesity, thus highlighting the emerging concept of selectively inhibiting production or action of ceramides with specific acyl chain lengths as novel therapeutic strategies to ameliorate obesity-associated diseases.
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16
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Nampoothiri S, Nogueiras R, Schwaninger M, Prevot V. Glial cells as integrators of peripheral and central signals in the regulation of energy homeostasis. Nat Metab 2022; 4:813-825. [PMID: 35879459 PMCID: PMC7613794 DOI: 10.1038/s42255-022-00610-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 06/15/2022] [Indexed: 01/03/2023]
Abstract
Communication between the periphery and the brain is key for maintaining energy homeostasis. To do so, peripheral signals from the circulation reach the brain via the circumventricular organs (CVOs), which are characterized by fenestrated vessels lacking the protective blood-brain barrier (BBB). Glial cells, by virtue of their plasticity and their ideal location at the interface of blood vessels and neurons, participate in the integration and transmission of peripheral information to neuronal networks in the brain for the neuroendocrine control of whole-body metabolism. Metabolic diseases, such as obesity and type 2 diabetes, can disrupt the brain-to-periphery communication mediated by glial cells, highlighting the relevance of these cell types in the pathophysiology of such complications. An improved understanding of how glial cells integrate and respond to metabolic and humoral signals has become a priority for the discovery of promising therapeutic strategies to treat metabolic disorders. This Review highlights the role of glial cells in the exchange of metabolic signals between the periphery and the brain that are relevant for the regulation of whole-body energy homeostasis.
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Affiliation(s)
- Sreekala Nampoothiri
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France
| | - Ruben Nogueiras
- Universidade de Santiago de Compostela-Instituto de Investigation Sanitaria, Santiago de Compostela, Spain
- CIBER Fisiopatologia de la Obesidad y Nutrition, Santiago de Compostela, Spain
| | - Markus Schwaninger
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Vincent Prevot
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S1172, EGID, DISTALZ, Lille, France.
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17
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Sa M, Park MG, Lee CJ. Role of Hypothalamic Reactive Astrocytes in Diet-Induced Obesity. Mol Cells 2022; 45:65-75. [PMID: 35236781 PMCID: PMC8907000 DOI: 10.14348/molcells.2022.2044] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 01/07/2022] [Accepted: 01/12/2022] [Indexed: 11/30/2022] Open
Abstract
Hypothalamus is a brain region that controls food intake and energy expenditure while sensing signals that convey information about energy status. Within the hypothalamus, molecularly and functionally distinct neurons work in concert under physiological conditions. However, under pathological conditions such as in diet-induced obesity (DIO) model, these neurons show dysfunctional firing patterns and distorted regulation by neurotransmitters and neurohormones. Concurrently, resident glial cells including astrocytes dramatically transform into reactive states. In particular, it has been reported that reactive astrogliosis is observed in the hypothalamus, along with various neuroinflammatory signals. However, how the reactive astrocytes control and modulate DIO by influencing neighboring neurons is not well understood. Recently, new lines of evidence have emerged indicating that these reactive astrocytes directly contribute to the pathology of obesity by synthesizing and tonically releasing the major inhibitory transmitter GABA. The released GABA strongly inhibits the neighboring neurons that control energy expenditure. These surprising findings shed light on the interplay between reactive astrocytes and neighboring neurons in the hypothalamus. This review summarizes recent discoveries related to the functions of hypothalamic reactive astrocytes in obesity and raises new potential therapeutic targets against obesity.
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Affiliation(s)
- Moonsun Sa
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon 34126, Korea
| | - Mingu Gordon Park
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon 34126, Korea
| | - C. Justin Lee
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon 34126, Korea
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18
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Guo S, Cázarez-Márquez F, Jiao H, Foppen E, Korpel NL, Grootemaat AE, Liv N, Gao Y, van der Wel N, Zhou B, Nie G, Yi CX. Specific Silencing of Microglial Gene Expression in the Rat Brain by Nanoparticle-Based Small Interfering RNA Delivery. ACS APPLIED MATERIALS & INTERFACES 2022; 14:5066-5079. [PMID: 35041392 PMCID: PMC8815040 DOI: 10.1021/acsami.1c22434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 01/03/2022] [Indexed: 05/02/2023]
Abstract
Microglia are the major innate immune cells in the brain and are essential for maintaining homeostasis in a neuronal microenvironment. Currently, a genetic tool to modify microglial gene expression in specific brain regions is not available. In this report, we introduce a tailor-designed method that uses lipid and polymer hybridized nanoparticles (LPNPs) for the local delivery of small interfering RNAs (siRNAs), allowing the silencing of specific microglial genes in the hypothalamus. Our physical characterization proved that this LPNP-siRNA was uniform and stable. We demonstrated that, due to their natural phagocytic behavior, microglial cells are the dominant cell type taking up these LPNPs in the hypothalamus of rats. We then tested the silencing efficiency of LPNPs carrying a cluster of differentiation molecule 11b (CD11b) or Toll-like receptor 4 (TLR4) siRNA using different in vivo and in vitro approaches. In cultured microglial cells treated with LPNP-CD11b siRNA or LPNP-TLR4 siRNA, we found a silencing efficiency at protein expression levels of 65 or 77%, respectively. In line with this finding, immunohistochemistry and western blotting results from in vivo experiments showed that LPNP-CD11b siRNA significantly inhibited microglial CD11b protein expression in the hypothalamus. Furthermore, following lipopolysaccharide (LPS) stimulation of cultured microglial cells, gene expression of the TLR4 downstream signaling component myeloid differentiation factor 88 and its associated cytokines was significantly inhibited in LPNP-TLR4 siRNA-treated microglial cells compared with cells treated with LPNP-scrambled siRNA. Finally, after LPNP-TLR4 siRNA injection into the rat hypothalamus, we observed a significant reduction in microglial activation in response to LPS compared with the control rats injected with LPNP-scrambled siRNA. Our results indicate that LPNP-siRNA is a promising tool to manipulate microglial activity locally in the brain and may serve as a prophylactic approach to prevent microglial dysfunction-associated diseases.
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Affiliation(s)
- Shanshan Guo
- Department
of Endocrinology and Metabolism, Laboratory of Endocrinology, Amsterdam
Gastroenterology Endocrinology Metabolism Research Institute, Amsterdam
University Medical Centre (UMC), location AMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Fernando Cázarez-Márquez
- Department
of Endocrinology and Metabolism, Laboratory of Endocrinology, Amsterdam
Gastroenterology Endocrinology Metabolism Research Institute, Amsterdam
University Medical Centre (UMC), location AMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Netherlands
Institute for Neuroscience, Institute of
the Royal Netherlands Academy of Arts and Sciences, 1105 AZ Amsterdam, The Netherlands
| | - Han Jiao
- Department
of Endocrinology and Metabolism, Laboratory of Endocrinology, Amsterdam
Gastroenterology Endocrinology Metabolism Research Institute, Amsterdam
University Medical Centre (UMC), location AMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Key
Laboratory of Cardiovascular and Cerebrovascular Medicine, School
of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Ewout Foppen
- Department
of Endocrinology and Metabolism, Laboratory of Endocrinology, Amsterdam
Gastroenterology Endocrinology Metabolism Research Institute, Amsterdam
University Medical Centre (UMC), location AMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Netherlands
Institute for Neuroscience, Institute of
the Royal Netherlands Academy of Arts and Sciences, 1105 AZ Amsterdam, The Netherlands
| | - Nikita L. Korpel
- Department
of Endocrinology and Metabolism, Laboratory of Endocrinology, Amsterdam
Gastroenterology Endocrinology Metabolism Research Institute, Amsterdam
University Medical Centre (UMC), location AMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Netherlands
Institute for Neuroscience, Institute of
the Royal Netherlands Academy of Arts and Sciences, 1105 AZ Amsterdam, The Netherlands
| | - Anita E. Grootemaat
- Cellular
Imaging Core Facility, Amsterdam University Medical Centre (UMC),
location AMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Nalan Liv
- Section
Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
| | - Yuanqing Gao
- Key
Laboratory of Cardiovascular and Cerebrovascular Medicine, School
of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Nicole van der Wel
- Cellular
Imaging Core Facility, Amsterdam University Medical Centre (UMC),
location AMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Bing Zhou
- Institute
of Synthetic Biology, Shenzhen Institutes
of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Guangjun Nie
- CAS
Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology, Beijing 100190, China
| | - Chun-Xia Yi
- Department
of Endocrinology and Metabolism, Laboratory of Endocrinology, Amsterdam
Gastroenterology Endocrinology Metabolism Research Institute, Amsterdam
University Medical Centre (UMC), location AMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
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19
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Obara-Michlewska M. The contribution of astrocytes to obesity-associated metabolic disturbances. J Biomed Res 2022; 36:299-311. [PMID: 36131679 PMCID: PMC9548436 DOI: 10.7555/jbr.36.20200020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Marta Obara-Michlewska
- Department of Neurotoxicology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw 02-106, Poland
- Marta Obara-Michlewska, Department of Neurotoxicology, Mossakowski Medical Research Institute, Polish Academy of Sciences, 5 A. Pawinskiego Street, Warsaw 02-106, Poland. Tel/Fax: +48-22-6046416, E-mail:
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20
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Maly IV, Morales MJ, Pletnikov MV. Astrocyte Bioenergetics and Major Psychiatric Disorders. ADVANCES IN NEUROBIOLOGY 2021; 26:173-227. [PMID: 34888836 DOI: 10.1007/978-3-030-77375-5_9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Ongoing research continues to add new elements to the emerging picture of involvement of astrocyte energy metabolism in the pathophysiology of major psychiatric disorders, including schizophrenia, mood disorders, and addictions. This review outlines what is known about the energy metabolism in astrocytes, the most numerous cell type in the brain, and summarizes the recent work on how specific perturbations of astrocyte bioenergetics may contribute to the neuropsychiatric conditions. The role of astrocyte energy metabolism in mental health and disease is reviewed on the organism, organ, and cell level. Data arising from genomic, metabolomic, in vitro, and neurobehavioral studies is critically analyzed to suggest future directions in research and possible metabolism-focused therapeutic interventions.
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Affiliation(s)
- Ivan V Maly
- Department of Physiology and Biophysics, Jacobs School of Medicine and Biomedical Sciences, State University of New York, Buffalo, NY, USA
| | - Michael J Morales
- Department of Physiology and Biophysics, Jacobs School of Medicine and Biomedical Sciences, State University of New York, Buffalo, NY, USA
| | - Mikhail V Pletnikov
- Department of Physiology and Biophysics, Jacobs School of Medicine and Biomedical Sciences, State University of New York, Buffalo, NY, USA.
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21
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Varela L, Kim JG, Fernández-Tussy P, Aryal B, Liu ZW, Fernández-Hernando C, Horvath TL. Astrocytic lipid metabolism determines susceptibility to diet-induced obesity. SCIENCE ADVANCES 2021; 7:eabj2814. [PMID: 34890239 DOI: 10.1126/sciadv.abj2814] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Hypothalamic astrocytes play pivotal roles in both nutrient sensing and the modulation of synaptic plasticity of hypothalamic neuronal circuits in control of feeding and systemic glucose and energy metabolism. Here, we show the relevance of astrocytic fatty acid (FA) homeostasis under the opposing control of angiopoietin-like 4 (ANGPTL-4) and peroxisome proliferator–activated receptor gamma (PPARγ) in the cellular adaptations of hypothalamic astrocytes and neurons to the changing metabolic milieu. We observed that increased availability of FA in astrocytes induced by cell- and time-selective knockdown of Angptl4 protected against diet-induced obesity, while cell- and time-selective knockdown of Angptl4-regulated Pparγ lead to elevated susceptibility to obesity. Overall, our results unravel a previously unidentified role for astrocytic FA metabolism in central control of body weight and glucose homeostasis.
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Affiliation(s)
- Luis Varela
- Department of Comparative Medicine, Yale University School of Medicine, 310 Cedar St., BML 330, New Haven, CT 06520, USA
- Yale Center for Molecular and Systems Metabolism, Yale University School of Medicine, 310 Cedar St., BML 330, New Haven, CT 06520, USA
| | - Jae Geun Kim
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 406-772, South Korea
| | - Pablo Fernández-Tussy
- Department of Comparative Medicine, Yale University School of Medicine, 310 Cedar St., BML 330, New Haven, CT 06520, USA
- Vascular Biology and Therapeutics Program, School of Medicine, Yale University, New Haven, CT 06510, USA
| | - Binod Aryal
- Department of Comparative Medicine, Yale University School of Medicine, 310 Cedar St., BML 330, New Haven, CT 06520, USA
- Vascular Biology and Therapeutics Program, School of Medicine, Yale University, New Haven, CT 06510, USA
| | - Zhong Wu Liu
- Department of Comparative Medicine, Yale University School of Medicine, 310 Cedar St., BML 330, New Haven, CT 06520, USA
- Yale Center for Molecular and Systems Metabolism, Yale University School of Medicine, 310 Cedar St., BML 330, New Haven, CT 06520, USA
| | - Carlos Fernández-Hernando
- Department of Comparative Medicine, Yale University School of Medicine, 310 Cedar St., BML 330, New Haven, CT 06520, USA
- Yale Center for Molecular and Systems Metabolism, Yale University School of Medicine, 310 Cedar St., BML 330, New Haven, CT 06520, USA
- Vascular Biology and Therapeutics Program, School of Medicine, Yale University, New Haven, CT 06510, USA
| | - Tamas L Horvath
- Department of Comparative Medicine, Yale University School of Medicine, 310 Cedar St., BML 330, New Haven, CT 06520, USA
- Yale Center for Molecular and Systems Metabolism, Yale University School of Medicine, 310 Cedar St., BML 330, New Haven, CT 06520, USA
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Astrocyte Gliotransmission in the Regulation of Systemic Metabolism. Metabolites 2021; 11:metabo11110732. [PMID: 34822390 PMCID: PMC8623475 DOI: 10.3390/metabo11110732] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 12/28/2022] Open
Abstract
Normal brain function highly relies on the appropriate functioning of astrocytes. These glial cells are strategically situated between blood vessels and neurons, provide significant substrate support to neuronal demand, and are sensitive to neuronal activity and energy-related molecules. Astrocytes respond to many metabolic conditions and regulate a wide array of physiological processes, including cerebral vascular remodeling, glucose sensing, feeding, and circadian rhythms for the control of systemic metabolism and behavior-related responses. This regulation ultimately elicits counterregulatory mechanisms in order to couple whole-body energy availability with brain function. Therefore, understanding the role of astrocyte crosstalk with neighboring cells via the release of molecules, e.g., gliotransmitters, into the parenchyma in response to metabolic and neuronal cues is of fundamental relevance to elucidate the distinct roles of these glial cells in the neuroendocrine control of metabolism. Here, we review the mechanisms underlying astrocyte-released gliotransmitters that have been reported to be crucial for maintaining homeostatic regulation of systemic metabolism.
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Berland C, Small DM, Luquet S, Gangarossa G. Dietary lipids as regulators of reward processes: multimodal integration matters. Trends Endocrinol Metab 2021; 32:693-705. [PMID: 34148784 DOI: 10.1016/j.tem.2021.05.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/08/2021] [Accepted: 05/24/2021] [Indexed: 02/03/2023]
Abstract
The abundance of energy-dense and palatable diets in the modern food environment tightly contributes to the obesity pandemic. The reward circuit participates to the regulation of body homeostasis by integrating energy-related signals with neural substrates encoding cognitive and motivational components of feeding behaviors. Obesity and lipid-rich diets alter dopamine (DA) transmission leading to reward dysfunctions and food overconsumption. Recent reports indicate that dietary lipids can act, directly and indirectly, as functional modulators of the DA circuit. This raises the possibility that nutritional or genetic conditions affecting 'lipid sensing' mechanisms might lead to maladaptations of the DA system. Here, we discuss the most recent findings connecting dietary lipid sensing with DA signaling and its multimodal influence on circuits regulating food-reward processes.
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Affiliation(s)
- Chloé Berland
- Université de Paris, BFA, UMR 8251, CNRS, F-75013 Paris, France; Department of Medicine, The Naomi Berrie Diabetes Center, Columbia University, New York, NY 10032, USA
| | - Dana M Small
- Department of Psychiatry, and the Modern Diet and Physiology Research Center, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Serge Luquet
- Université de Paris, BFA, UMR 8251, CNRS, F-75013 Paris, France.
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Magnan C, Le Stunff H. Role of hypothalamic de novo ceramides synthesis in obesity and associated metabolic disorders. Mol Metab 2021; 53:101298. [PMID: 34273578 PMCID: PMC8353504 DOI: 10.1016/j.molmet.2021.101298] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 06/28/2021] [Accepted: 07/09/2021] [Indexed: 12/31/2022] Open
Abstract
Background Sphingolipid-mediated signalling pathways are described as important players in the normal functioning of neurons and nonneuronal cells in the central nervous system (CNS). Scope of review This review aims to show role of de novo ceramide synthesis in the CNS in controling key physiological processes, including food intake, energy expenditure, and thermogenesis. The corollary is a condition that leads to a dysfunction in ceramide metabolism in these central regions that can have major consequences on the physiological regulation of energy balance. Major conclusions Excessive hypothalamic de novo ceramide synthesis has been shown to result in the establishment of central insulin resistance, endoplasmic reticulum stress, and inflammation. Additionally, excessive hypothalamic de novo ceramide synthesis has also been associated with changes in the activity of the autonomic nervous system. Such dysregulation of hypothalamic de novo ceramide synthesis forms the key starting point for the initiation of pathophysiological conditions such as obesity – which may or may not be associated with type 2 diabetes.
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Affiliation(s)
| | - Hervé Le Stunff
- CNRS UMR 9198 Institut des Neurosciences Paris Saclay (Neuro-PSI), Université Paris-Saclay, Saclay, France.
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25
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Price BR, Johnson LA, Norris CM. Reactive astrocytes: The nexus of pathological and clinical hallmarks of Alzheimer's disease. Ageing Res Rev 2021; 68:101335. [PMID: 33812051 PMCID: PMC8168445 DOI: 10.1016/j.arr.2021.101335] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 01/21/2021] [Accepted: 03/20/2021] [Indexed: 02/06/2023]
Abstract
Astrocyte reactivity is a hallmark of neuroinflammation that arises with Alzheimer’s disease (AD) and nearly every other neurodegenerative condition. While astrocytes certainly contribute to classic inflammatory processes (e.g. cytokine release, waste clearance, and tissue repair), newly emerging technologies for measuring and targeting cell specific activities in the brain have uncovered essential roles for astrocytes in synapse function, brain metabolism, neurovascular coupling, and sleep/wake patterns. In this review, we use a holistic approach to incorporate, and expand upon, classic neuroinflammatory concepts to consider how astrocyte dysfunction/reactivity modulates multiple pathological and clinical hallmarks of AD. Our ever-evolving understanding of astrocyte signaling in neurodegeneration is not only revealing new drug targets and treatments for dementia but is suggesting we reimagine AD pathophysiological mechanisms.
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Affiliation(s)
- Brittani R Price
- Department of Neuroscience, Tufts University School of Medicine, 136 Harrison Ave., Boston, MA, 02111, USA
| | - Lance A Johnson
- Sanders-Brown Center on Aging, University of Kentucky, 800 S. Limestone St., Lexington, KY, 40356, USA; Department of Physiology, University of Kentucky, College of Medicine, UK Medical Center MN 150, Lexington, KY, 40536, USA
| | - Christopher M Norris
- Sanders-Brown Center on Aging, University of Kentucky, 800 S. Limestone St., Lexington, KY, 40356, USA; Department of Pharmacology and Nutritional Sciences, University of Kentucky, College of Medicine, UK Medical Center MN 150, Lexington, KY, 40536, USA.
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26
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Hypothalamic Astrocytes as a Specialized and Responsive Cell Population in Obesity. Int J Mol Sci 2021; 22:ijms22126176. [PMID: 34201099 PMCID: PMC8228119 DOI: 10.3390/ijms22126176] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/03/2021] [Accepted: 06/04/2021] [Indexed: 12/11/2022] Open
Abstract
Astrocytes are a type of glial cell anatomically and functionally integrated into the neuronal regulatory circuits for the neuroendocrine control of metabolism. Being functional integral compounds of synapses, astrocytes are actively involved in the physiological regulatory aspects of metabolic control, but also in the pathological processes that link neuronal dysfunction and obesity. Between brain areas, the hypothalamus harbors specialized functional circuits that seem selectively vulnerable to metabolic damage, undergoing early cellular rearrangements which are thought to be at the core of the pathogenesis of diet-induced obesity. Such changes in the hypothalamic brain region consist of a rise in proinflammatory cytokines, the presence of a reactive phenotype in astrocytes and microglia, alterations in the cytoarchitecture and synaptology of hypothalamic circuits, and angiogenesis, a phenomenon that cannot be found elsewhere in the brain. Increasing evidence points to the direct involvement of hypothalamic astrocytes in such early metabolic disturbances, thus moving the study of these glial cells to the forefront of obesity research. Here we provide a comprehensive review of the most relevant findings of molecular and pathophysiological mechanisms by which hypothalamic astrocytes might be involved in the pathogenesis of obesity.
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Obesity-associated hyperleptinemia alters the gliovascular interface of the hypothalamus to promote hypertension. Cell Metab 2021; 33:1155-1170.e10. [PMID: 33951475 PMCID: PMC8183500 DOI: 10.1016/j.cmet.2021.04.007] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 02/27/2021] [Accepted: 04/12/2021] [Indexed: 12/21/2022]
Abstract
Pathologies of the micro- and macrovascular systems are a hallmark of the metabolic syndrome, which can lead to chronically elevated blood pressure. However, the underlying pathomechanisms involved still need to be clarified. Here, we report that an obesity-associated increase in serum leptin triggers the select expansion of the micro-angioarchitecture in pre-autonomic brain centers that regulate hemodynamic homeostasis. By using a series of cell- and region-specific loss- and gain-of-function models, we show that this pathophysiological process depends on hypothalamic astroglial hypoxia-inducible factor 1α-vascular endothelial growth factor (HIF1α-VEGF) signaling downstream of leptin signaling. Importantly, several distinct models of HIF1α-VEGF pathway disruption in astrocytes are protected not only from obesity-induced hypothalamic angiopathy but also from sympathetic hyperactivity or arterial hypertension. These results suggest that hyperleptinemia promotes obesity-induced hypertension via a HIF1α-VEGF signaling cascade in hypothalamic astrocytes while establishing a novel mechanistic link that connects hypothalamic micro-angioarchitecture with control over systemic blood pressure.
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Reginato A, Veras ACC, Baqueiro MDN, Panzarin C, Siqueira BP, Milanski M, Lisboa PC, Torsoni AS. The Role of Fatty Acids in Ceramide Pathways and Their Influence on Hypothalamic Regulation of Energy Balance: A Systematic Review. Int J Mol Sci 2021; 22:5357. [PMID: 34069652 PMCID: PMC8160791 DOI: 10.3390/ijms22105357] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 04/30/2021] [Accepted: 05/06/2021] [Indexed: 12/09/2022] Open
Abstract
Obesity is a global health issue for which no major effective treatments have been well established. High-fat diet consumption is closely related to the development of obesity because it negatively modulates the hypothalamic control of food intake due to metaflammation and lipotoxicity. The use of animal models, such as rodents, in conjunction with in vitro models of hypothalamic cells, can enhance the understanding of hypothalamic functions related to the control of energy balance, thereby providing knowledge about the impact of diet on the hypothalamus, in addition to targets for the development of new drugs that can be used in humans to decrease body weight. Recently, sphingolipids were described as having a lipotoxic effect in peripheral tissues and the central nervous system. Specifically, lipid overload, mainly from long-chain saturated fatty acids, such as palmitate, leads to excessive ceramide levels that can be sensed by the hypothalamus, triggering the dysregulation of energy balance control. However, no systematic review has been undertaken regarding studies of sphingolipids, particularly ceramide and sphingosine-1-phosphate (S1P), the hypothalamus, and obesity. This review confirms that ceramides are associated with hypothalamic dysfunction in response to metaflammation, endoplasmic reticulum (ER) stress, and lipotoxicity, leading to insulin/leptin resistance. However, in contrast to ceramide, S1P appears to be a central satiety factor in the hypothalamus. Thus, our work describes current evidence related to sphingolipids and their role in hypothalamic energy balance control. Hypothetically, the manipulation of sphingolipid levels could be useful in enabling clinicians to treat obesity, particularly by decreasing ceramide levels and the inflammation/endoplasmic reticulum stress induced in response to overfeeding with saturated fatty acids.
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Affiliation(s)
- Andressa Reginato
- Biology Institute, State University of Rio de Janeiro, UERJ, Rio de Janeiro 20551-030, Brazil;
- Faculty of Applied Science, University of Campinas, UNICAMP, Campinas 13484-350, Brazil; (A.C.C.V.); (M.d.N.B.); (C.P.); (B.P.S.); (M.M.)
- Obesity and Comorbidities Research Center, University of Campinas, UNICAMP, Campinas 13083-864, Brazil
| | - Alana Carolina Costa Veras
- Faculty of Applied Science, University of Campinas, UNICAMP, Campinas 13484-350, Brazil; (A.C.C.V.); (M.d.N.B.); (C.P.); (B.P.S.); (M.M.)
- Obesity and Comorbidities Research Center, University of Campinas, UNICAMP, Campinas 13083-864, Brazil
| | - Mayara da Nóbrega Baqueiro
- Faculty of Applied Science, University of Campinas, UNICAMP, Campinas 13484-350, Brazil; (A.C.C.V.); (M.d.N.B.); (C.P.); (B.P.S.); (M.M.)
- Obesity and Comorbidities Research Center, University of Campinas, UNICAMP, Campinas 13083-864, Brazil
| | - Carolina Panzarin
- Faculty of Applied Science, University of Campinas, UNICAMP, Campinas 13484-350, Brazil; (A.C.C.V.); (M.d.N.B.); (C.P.); (B.P.S.); (M.M.)
- Obesity and Comorbidities Research Center, University of Campinas, UNICAMP, Campinas 13083-864, Brazil
| | - Beatriz Piatezzi Siqueira
- Faculty of Applied Science, University of Campinas, UNICAMP, Campinas 13484-350, Brazil; (A.C.C.V.); (M.d.N.B.); (C.P.); (B.P.S.); (M.M.)
- Obesity and Comorbidities Research Center, University of Campinas, UNICAMP, Campinas 13083-864, Brazil
| | - Marciane Milanski
- Faculty of Applied Science, University of Campinas, UNICAMP, Campinas 13484-350, Brazil; (A.C.C.V.); (M.d.N.B.); (C.P.); (B.P.S.); (M.M.)
- Obesity and Comorbidities Research Center, University of Campinas, UNICAMP, Campinas 13083-864, Brazil
| | | | - Adriana Souza Torsoni
- Faculty of Applied Science, University of Campinas, UNICAMP, Campinas 13484-350, Brazil; (A.C.C.V.); (M.d.N.B.); (C.P.); (B.P.S.); (M.M.)
- Obesity and Comorbidities Research Center, University of Campinas, UNICAMP, Campinas 13083-864, Brazil
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Abstract
Background The brain was once thought of as an insulin-insensitive organ. We now know that the insulin receptor is present throughout the brain and serves important functions in whole-body metabolism and brain function. Brain insulin signaling is involved not only in brain homeostatic processes but also neuropathological processes such as cognitive decline and Alzheimer's disease. Scope of review In this review, we provide an overview of insulin signaling within the brain and the metabolic impact of brain insulin resistance and discuss Alzheimer's disease, one of the neurologic diseases most closely associated with brain insulin resistance. Major conclusions While brain insulin signaling plays only a small role in central nervous system glucose regulation, it has a significant impact on the brain's metabolic health. Normal insulin signaling is important for mitochondrial functioning and normal food intake. Brain insulin resistance contributes to obesity and may also play an important role in neurodegeneration. Insulin is an important regulator of brain metabolism. Brain insulin signaling helps regulate whole body metabolism. Brain insulin signaling may play an important role in the pathogenesis of Alzheimer's disease.
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30
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Abstract
The endogenous timekeeping system evolved to anticipate the time of the day through the 24 hours cycle of the Earth's rotation. In mammals, the circadian clock governs rhythmic physiological and behavioral processes, including the daily oscillation in glucose metabolism, food intake, energy expenditure, and whole-body insulin sensitivity. The results from a series of studies have demonstrated that environmental or genetic alterations of the circadian cycle in humans and rodents are strongly associated with metabolic diseases such as obesity and type 2 diabetes. Emerging evidence suggests that astrocyte clocks have a crucial role in regulating molecular, physiological, and behavioral circadian rhythms such as glucose metabolism and insulin sensitivity. Given the concurrent high prevalence of type 2 diabetes and circadian disruption, understanding the mechanisms underlying glucose homeostasis regulation by the circadian clock and its dysregulation may improve glycemic control. In this review, we summarize the current knowledge on the tight interconnection between the timekeeping system, glucose homeostasis, and insulin sensitivity. We focus specifically on the involvement of astrocyte clocks, at the organism, cellular, and molecular levels, in the regulation of glucose metabolism.
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Affiliation(s)
- Olga Barca-Mayo
- Circadian and Glial Biology Lab, Physiology Department, Molecular Medicine and Chronic Diseases Research Centre (CiMUS), University of Santiago de Compostela, Santiago de Compostela, Spain
| | - Miguel López
- NeurObesity Lab, Physiology Department, Molecular Medicine and Chronic Diseases Research Centre (CiMUS), University of Santiago de Compostela, Santiago de Compostela, Spain
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31
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Hundahl C, Kotzbeck P, Burm HB, Christiansen SH, Torz L, Helge AW, Madsen MP, Ratner C, Serup AK, Thompson JJ, Eichmann TO, Pers TH, Woldbye DPD, Piomelli D, Kiens B, Zechner R, Skov LJ, Holst B. Hypothalamic hormone-sensitive lipase regulates appetite and energy homeostasis. Mol Metab 2021; 47:101174. [PMID: 33549847 PMCID: PMC7903013 DOI: 10.1016/j.molmet.2021.101174] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/22/2021] [Accepted: 01/25/2021] [Indexed: 12/26/2022] Open
Abstract
Objective The goal of this study was to investigate the importance of central hormone-sensitive lipase (HSL) expression in the regulation of food intake and body weight in mice to clarify whether intracellular lipolysis in the mammalian hypothalamus plays a role in regulating appetite. Methods Using pharmacological and genetic approaches, we investigated the role of HSL in the rodent brain in the regulation of feeding and energy homeostasis under basal conditions during acute stress and high-fat diet feeding. Results We found that HSL, a key enzyme in the catabolism of cellular lipid stores, is expressed in the appetite-regulating centers in the hypothalamus and is activated by acute stress through a mechanism similar to that observed in adipose tissue and skeletal muscle. Inhibition of HSL in rodent models by a synthetic ligand, global knockout, or brain-specific deletion of HSL prevents a decrease in food intake normally seen in response to acute stress and is associated with the increased expression of orexigenic peptides neuropeptide Y (NPY) and agouti-related peptide (AgRP). Increased food intake can be reversed by adeno-associated virus-mediated reintroduction of HSL in neurons of the mediobasal hypothalamus. Importantly, metabolic stress induced by a high-fat diet also enhances the hyperphagic phenotype of HSL-deficient mice. Specific deletion of HSL in the ventromedial hypothalamic nucleus (VMH) or AgRP neurons reveals that HSL in the VMH plays a role in both acute stress-induced food intake and high-fat diet-induced obesity. Conclusions Our results indicate that HSL activity in the mediobasal hypothalamus is involved in the acute reduction in food intake during the acute stress response and sensing of a high-fat diet. HSL is expressed in appetite-regulating nuclei of the mouse hypothalamus. HSL in the hypothalamus is activated via β-adrenergic receptor signaling. The anorexic response to acute stress is blunted in mice without hypothalamic HSL. Central HSL deficiency results in obesity in mice on a high-fat diet. HSL in SF1-positive neurons contributes to the anorexigenic stress response.
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Affiliation(s)
- Cecilie Hundahl
- Department of Biomedical Sciences, University of Copenhagen, 2200 Copenhagen N, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Petra Kotzbeck
- Institute of Molecular Biosciences, University of Graz, Graz, Austria; Division of Endocrinology and Diabetology, Medical University of Graz, Graz, Austria
| | - Hayley B Burm
- Department of Biomedical Sciences, University of Copenhagen, 2200 Copenhagen N, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Søren H Christiansen
- Department of Neuroscience, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Lola Torz
- Department of Biomedical Sciences, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Aske W Helge
- Department of Biomedical Sciences, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Martin P Madsen
- Department of Biomedical Sciences, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Cecilia Ratner
- Department of Biomedical Sciences, University of Copenhagen, 2200 Copenhagen N, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Annette K Serup
- Department of Nutrition, Exercise and Sports, University of Copenhagen, 2100 Copenhagen Ø, Denmark
| | - Jonatan J Thompson
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Thomas O Eichmann
- Institute of Molecular Biosciences, University of Graz, Graz, Austria; Center for Explorative Lipidomics, BioTechMed-Graz, Graz, Austria
| | - Tune H Pers
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - David P D Woldbye
- Department of Neuroscience, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Daniele Piomelli
- Center for Explorative Lipidomics, BioTechMed-Graz, Graz, Austria; Department of Anatomy and Neurobiology, University of California, Irvine, CA, USA
| | - Bente Kiens
- Department of Nutrition, Exercise and Sports, University of Copenhagen, 2100 Copenhagen Ø, Denmark
| | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Louise J Skov
- Department of Biomedical Sciences, University of Copenhagen, 2200 Copenhagen N, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Birgitte Holst
- Department of Biomedical Sciences, University of Copenhagen, 2200 Copenhagen N, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, 2200 Copenhagen N, Denmark.
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Song N, Jeong DY, Tu TH, Park BS, Yang HR, Kim YJ, Kim JK, Park JT, Yeh JY, Yang S, Kim JG. Adiponectin Controls Nutrient Availability in Hypothalamic Astrocytes. Int J Mol Sci 2021; 22:ijms22041587. [PMID: 33557390 PMCID: PMC7915184 DOI: 10.3390/ijms22041587] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/27/2021] [Accepted: 02/01/2021] [Indexed: 12/12/2022] Open
Abstract
Adiponectin, an adipose tissue-derived hormone, plays integral roles in lipid and glucose metabolism in peripheral tissues, such as the skeletal muscle, adipose tissue, and liver. Moreover, it has also been shown to have an impact on metabolic processes in the central nervous system. Astrocytes comprise the most abundant cell type in the central nervous system and actively participate in metabolic processes between blood vessels and neurons. However, the ability of adiponectin to control nutrient metabolism in astrocytes has not yet been fully elucidated. In this study, we investigated the effects of adiponectin on multiple metabolic processes in hypothalamic astrocytes. Adiponectin enhanced glucose uptake, glycolytic processes and fatty acid oxidation in cultured primary hypothalamic astrocytes. In line with these findings, we also found that adiponectin treatment effectively enhanced synthesis and release of monocarboxylates. Overall, these data suggested that adiponectin triggers catabolic processes in astrocytes, thereby enhancing nutrient availability in the hypothalamus.
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Affiliation(s)
- Nuri Song
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 406-772, Korea; (N.S.); (D.Y.J.); (T.H.T.); (H.R.Y.); (Y.J.K.); (J.K.K.); (J.T.P.); (J.-Y.Y.)
| | - Da Yeon Jeong
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 406-772, Korea; (N.S.); (D.Y.J.); (T.H.T.); (H.R.Y.); (Y.J.K.); (J.K.K.); (J.T.P.); (J.-Y.Y.)
| | - Thai Hien Tu
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 406-772, Korea; (N.S.); (D.Y.J.); (T.H.T.); (H.R.Y.); (Y.J.K.); (J.K.K.); (J.T.P.); (J.-Y.Y.)
| | - Byong Seo Park
- Department of Biological Science, University of Ulsan, Ulsan 44610, Korea;
| | - Hye Rim Yang
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 406-772, Korea; (N.S.); (D.Y.J.); (T.H.T.); (H.R.Y.); (Y.J.K.); (J.K.K.); (J.T.P.); (J.-Y.Y.)
| | - Ye Jin Kim
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 406-772, Korea; (N.S.); (D.Y.J.); (T.H.T.); (H.R.Y.); (Y.J.K.); (J.K.K.); (J.T.P.); (J.-Y.Y.)
| | - Jae Kwang Kim
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 406-772, Korea; (N.S.); (D.Y.J.); (T.H.T.); (H.R.Y.); (Y.J.K.); (J.K.K.); (J.T.P.); (J.-Y.Y.)
| | - Joon Tae Park
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 406-772, Korea; (N.S.); (D.Y.J.); (T.H.T.); (H.R.Y.); (Y.J.K.); (J.K.K.); (J.T.P.); (J.-Y.Y.)
| | - Jung-Yong Yeh
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 406-772, Korea; (N.S.); (D.Y.J.); (T.H.T.); (H.R.Y.); (Y.J.K.); (J.K.K.); (J.T.P.); (J.-Y.Y.)
| | - Sunggu Yang
- Department of Nano-Bioengineering, Incheon National University, Incheon 406-772, Korea
- Correspondence: (S.Y.); (J.G.K.); Tel.: +82-32-835-8257 (S.Y.); +82-32-835-8256 (J.G.K.)
| | - Jae Geun Kim
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 406-772, Korea; (N.S.); (D.Y.J.); (T.H.T.); (H.R.Y.); (Y.J.K.); (J.K.K.); (J.T.P.); (J.-Y.Y.)
- Correspondence: (S.Y.); (J.G.K.); Tel.: +82-32-835-8257 (S.Y.); +82-32-835-8256 (J.G.K.)
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D. Bruce K, Tang M, Reigan P, H. Eckel R. Genetic Variants of Lipoprotein Lipase and Regulatory Factors Associated with Alzheimer's Disease Risk. Int J Mol Sci 2020; 21:ijms21218338. [PMID: 33172164 PMCID: PMC7664401 DOI: 10.3390/ijms21218338] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 11/02/2020] [Accepted: 11/04/2020] [Indexed: 12/14/2022] Open
Abstract
Lipoprotein lipase (LPL) is a key enzyme in lipid and lipoprotein metabolism. The canonical role of LPL involves the hydrolysis of triglyceride-rich lipoproteins for the provision of FFAs to metabolic tissues. However, LPL may also contribute to lipoprotein uptake by acting as a molecular bridge between lipoproteins and cell surface receptors. Recent studies have shown that LPL is abundantly expressed in the brain and predominantly expressed in the macrophages and microglia of the human and murine brain. Moreover, recent findings suggest that LPL plays a direct role in microglial function, metabolism, and phagocytosis of extracellular factors such as amyloid- beta (Aβ). Although the precise function of LPL in the brain remains to be determined, several studies have implicated LPL variants in Alzheimer's disease (AD) risk. For example, while mutations shown to have a deleterious effect on LPL function and expression (e.g., N291S, HindIII, and PvuII) have been associated with increased AD risk, a mutation associated with increased bridging function (S447X) may be protective against AD. Recent studies have also shown that genetic variants in endogenous LPL activators (ApoC-II) and inhibitors (ApoC-III) can increase and decrease AD risk, respectively, consistent with the notion that LPL may play a protective role in AD pathogenesis. Here, we review recent advances in our understanding of LPL structure and function, which largely point to a protective role of functional LPL in AD neuropathogenesis.
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Affiliation(s)
- Kimberley D. Bruce
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; (M.T.); (R.H.E.)
- Correspondence:
| | - Maoping Tang
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; (M.T.); (R.H.E.)
| | - Philip Reigan
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
| | - Robert H. Eckel
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; (M.T.); (R.H.E.)
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Robb JL, Morrissey NA, Weightman Potter PG, Smithers HE, Beall C, Ellacott KLJ. Immunometabolic Changes in Glia - A Potential Role in the Pathophysiology of Obesity and Diabetes. Neuroscience 2020; 447:167-181. [PMID: 31765625 PMCID: PMC7567742 DOI: 10.1016/j.neuroscience.2019.10.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 10/10/2019] [Accepted: 10/11/2019] [Indexed: 12/15/2022]
Abstract
Chronic low-grade inflammation is a feature of the pathophysiology of obesity and diabetes in the CNS as well as peripheral tissues. Glial cells are critical mediators of the response to inflammation in the brain. Key features of glia include their metabolic flexibility, sensitivity to changes in the CNS microenvironment, and ability to rapidly adapt their function accordingly. They are specialised cells which cooperate to promote and preserve neuronal health, playing important roles in regulating the activity of neuronal networks across the brain during different life stages. Increasing evidence points to a role of glia, most notably astrocytes and microglia, in the systemic regulation of energy and glucose homeostasis in the course of normal physiological control and during disease. Inflammation is an energetically expensive process that requires adaptive changes in cellular metabolism and, in turn, metabolic intermediates can also have immunomodulatory actions. Such "immunometabolic" changes in peripheral immune cells have been implicated in contributing to disease pathology in obesity and diabetes. This review will discuss the evidence for a role of immunometabolic changes in glial cells in the systemic regulation of energy and glucose homeostasis, and how this changes in the context of obesity and diabetes.
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Affiliation(s)
- Josephine L Robb
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Nicole A Morrissey
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Paul G Weightman Potter
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Hannah E Smithers
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Craig Beall
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Kate L J Ellacott
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK.
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35
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Mens Sana in Corpore Sano: Does the Glycemic Index Have a Role to Play? Nutrients 2020; 12:nu12102989. [PMID: 33003562 PMCID: PMC7599769 DOI: 10.3390/nu12102989] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 09/25/2020] [Accepted: 09/27/2020] [Indexed: 12/20/2022] Open
Abstract
Although diet interventions are mostly related to metabolic disorders, nowadays they are used in a wide variety of pathologies. From diabetes and obesity to cardiovascular diseases, to cancer or neurological disorders and stroke, nutritional recommendations are applied to almost all diseases. Among such disorders, metabolic disturbances and brain function and/or diseases have recently been shown to be linked. Indeed, numerous neurological functions are often associated with perturbations of whole-body energy homeostasis. In this regard, specific diets are used in various neurological conditions, such as epilepsy, stroke, or seizure recovery. In addition, Alzheimer’s disease and Autism Spectrum Disorders are also considered to be putatively improved by diet interventions. Glycemic index diets are a novel developed indicator expected to anticipate the changes in blood glucose induced by specific foods and how they can affect various physiological functions. Several results have provided indications of the efficiency of low-glycemic index diets in weight management and insulin sensitivity, but also cognitive function, epilepsy treatment, stroke, and neurodegenerative diseases. Overall, studies involving the glycemic index can provide new insights into the relationship between energy homeostasis regulation and brain function or related disorders. Therefore, in this review, we will summarize the main evidence on glycemic index involvement in brain mechanisms of energy homeostasis regulation.
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36
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Heni M, Eckstein SS, Schittenhelm J, Böhm A, Hogrefe N, Irmler M, Beckers J, Hrabě de Angelis M, Häring HU, Fritsche A, Staiger H. Ectopic fat accumulation in human astrocytes impairs insulin action. ROYAL SOCIETY OPEN SCIENCE 2020; 7:200701. [PMID: 33047031 PMCID: PMC7540778 DOI: 10.1098/rsos.200701] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 08/12/2020] [Indexed: 05/13/2023]
Abstract
Astrocytes provide neurons with structural support and energy in form of lactate, modulate synaptic transmission, are insulin sensitive and act as gatekeeper for water, ions, glutamate and second messengers. Furthermore, astrocytes are important for glucose sensing, possess neuroendocrine functions and also play an important role in cerebral lipid metabolism. To answer the question, if there is a connection between lipid metabolism and insulin action in human astrocytes, we investigated if storage of ectopic lipids in human astrocytes has an impact on insulin signalling in those cells. Human astrocytes were cultured in the presence of a lipid emulsion, consisting of fatty acids and triglycerides, to induce ectopic lipid storage. After several days, cells were stimulated with insulin and gene expression profiling was performed. In addition, phosphorylation of Akt as well as glycogen synthesis and cell proliferation was assessed. Ectopic lipid storage was detected in human astrocytes after lipid exposure and lipid storage was persistent even when the fat emulsion was removed from the cell culture medium. Chronic exposure to lipids induced profound changes in the gene expression profile, whereby some genes showed a reversible gene expression profile upon removal of fat, and some did not. This included FOXO-dependent expression patterns. Furthermore, insulin-induced phosphorylation of Akt was diminished and also insulin-induced glycogen synthesis and proliferation was impaired in lipid-laden astrocytes. Chronic lipid exposure induces lipid storage in human astrocytes accompanied by insulin resistance. Analyses of the gene expression pattern indicated the potential of a partially reversible gene expression profile. Targeting astrocytic insulin resistance by reducing ectopic lipid load might represent a promising treatment target for insulin resistance of the brain in obesity, diabetes and neurodegeneration.
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Affiliation(s)
- Martin Heni
- Department of Internal Medicine, Division of Endocrinology, Diabetology, and Nephrology, Eberhard Karls University Tübingen, Tübingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Department for Diagnostic Laboratory Medicine, Institute for Clinical Chemistry and Pathobiochemistry, University Hospital Tübingen, Tübingen, Germany
- Author for correspondence: Martin Heni e-mail:
| | - Sabine S. Eckstein
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Jens Schittenhelm
- Division of Neuropathology, University Hospital Tübingen, Tübingen, Germany
| | - Anja Böhm
- Department of Internal Medicine, Division of Endocrinology, Diabetology, and Nephrology, Eberhard Karls University Tübingen, Tübingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Norbert Hogrefe
- Department of Physiology, University of Bern, Bern, Switzerland
| | - Martin Irmler
- Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Johannes Beckers
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
- Chair for Experimental Genetics, Technische Universität München, Freising, Germany
| | - Martin Hrabě de Angelis
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
- Chair for Experimental Genetics, Technische Universität München, Freising, Germany
| | - Hans-Ulrich Häring
- Department of Internal Medicine, Division of Endocrinology, Diabetology, and Nephrology, Eberhard Karls University Tübingen, Tübingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Andreas Fritsche
- Department of Internal Medicine, Division of Endocrinology, Diabetology, and Nephrology, Eberhard Karls University Tübingen, Tübingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Harald Staiger
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Institute of Pharmaceutical Sciences, Department of Pharmacy and Biochemistry, Eberhard Karls University Tübingen, Tübingen, Germany
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Kalsbeek MJ, Wolff SE, Korpel NL, la Fleur SE, Romijn JA, Fliers E, Kalsbeek A, Swaab DF, Huitinga I, Hol EM, Yi CX. The impact of antidiabetic treatment on human hypothalamic infundibular neurons and microglia. JCI Insight 2020; 5:133868. [PMID: 32814716 PMCID: PMC7455135 DOI: 10.1172/jci.insight.133868] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 07/08/2020] [Indexed: 12/22/2022] Open
Abstract
Animal studies indicate that hypothalamic dysfunction plays a major role in type 2 diabetes mellitus (T2DM) development, and that insulin resistance and inflammation are important mechanisms involved in this disorder. However, it remains unclear how T2DM and antidiabetic treatments affect the human hypothalamus. Here, we characterized the proopiomelanocortin (POMC) immunoreactive (-ir) neurons, the neuropeptide-Y-ir (NPY-ir) neurons, the ionized calcium-binding adapter molecule 1-ir (iba1-ir) microglia, and the transmembrane protein 119-ir (TMEM119-ir) microglia in the infundibular nucleus (IFN) of human postmortem hypothalamus of 32 T2DM subjects with different antidiabetic treatments and 17 matched nondiabetic control subjects. Compared with matched control subjects, T2DM subjects showed a decrease in the number of POMC-ir neurons, but no changes in NPY-ir neurons or microglia. Interestingly, T2DM subjects treated with the antidiabetic drug metformin had fewer NPY-ir neurons and microglia than T2DM subjects not treated with metformin. We found that the number of microglia correlated with the number of NPY-ir neurons, but only in T2DM subjects. These results indicate that different changes in POMC and NPY neurons and microglial cells in the IFN accompany T2DM. In addition, T2DM treatment modality is associated with highly selective changes in hypothalamic neurons and microglial cells.
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Affiliation(s)
- Martin Jt Kalsbeek
- Laboratory of Endocrinology, and.,Department of Endocrinology and Metabolism, Amsterdam University Medical Center (UMC), University of Amsterdam, Amsterdam, Netherlands.,Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Samantha Ec Wolff
- Laboratory of Endocrinology, and.,Department of Endocrinology and Metabolism, Amsterdam University Medical Center (UMC), University of Amsterdam, Amsterdam, Netherlands.,Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Nikita L Korpel
- Laboratory of Endocrinology, and.,Department of Endocrinology and Metabolism, Amsterdam University Medical Center (UMC), University of Amsterdam, Amsterdam, Netherlands.,Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Susanne E la Fleur
- Laboratory of Endocrinology, and.,Department of Endocrinology and Metabolism, Amsterdam University Medical Center (UMC), University of Amsterdam, Amsterdam, Netherlands.,Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Johannes A Romijn
- Department of Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Eric Fliers
- Department of Endocrinology and Metabolism, Amsterdam University Medical Center (UMC), University of Amsterdam, Amsterdam, Netherlands
| | - Andries Kalsbeek
- Laboratory of Endocrinology, and.,Department of Endocrinology and Metabolism, Amsterdam University Medical Center (UMC), University of Amsterdam, Amsterdam, Netherlands.,Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Dick F Swaab
- Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Inge Huitinga
- Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Elly M Hol
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, Netherlands
| | - Chun-Xia Yi
- Laboratory of Endocrinology, and.,Department of Endocrinology and Metabolism, Amsterdam University Medical Center (UMC), University of Amsterdam, Amsterdam, Netherlands.,Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
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38
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Lee JA, Hall B, Allsop J, Alqarni R, Allen SP. Lipid metabolism in astrocytic structure and function. Semin Cell Dev Biol 2020; 112:123-136. [PMID: 32773177 DOI: 10.1016/j.semcdb.2020.07.017] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 06/18/2020] [Accepted: 07/29/2020] [Indexed: 02/06/2023]
Abstract
Astrocytes are the most abundant glial cell in the central nervous system and are involved in multiple processes including metabolic homeostasis, blood brain barrier regulation and neuronal crosstalk. Astrocytes are the main storage point of glycogen in the brain and it is well established that astrocyte uptake of glutamate and release of lactate prevents neuronal excitability and supports neuronal metabolic function. However, the role of lipid metabolism in astrocytes in relation to neuronal support has been until recently, unclear. Lipids play a fundamental role in astrocyte function, including energy generation, membrane fluidity and cell to cell signaling. There is now emerging evidence that astrocyte storage of lipids in droplets has a crucial physiological and protective role in the central nervous system. This pathway links β-oxidation in astrocytes to inflammation, signalling, oxidative stress and mitochondrial energy generation in neurons. Disruption in lipid metabolism, structure and signalling in astrocytes can lead to pathogenic mechanisms associated with a range of neurological disorders.
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Affiliation(s)
- James Ak Lee
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385 Glossop Road, Sheffield, S10 2HQ, UK
| | - Benjamin Hall
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385 Glossop Road, Sheffield, S10 2HQ, UK
| | - Jessica Allsop
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385 Glossop Road, Sheffield, S10 2HQ, UK
| | - Razan Alqarni
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385 Glossop Road, Sheffield, S10 2HQ, UK
| | - Scott P Allen
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385 Glossop Road, Sheffield, S10 2HQ, UK.
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Cansell C, Stobbe K, Sanchez C, Le Thuc O, Mosser CA, Ben-Fradj S, Leredde J, Lebeaupin C, Debayle D, Fleuriot L, Brau F, Devaux N, Benani A, Audinat E, Blondeau N, Nahon JL, Rovère C. Dietary fat exacerbates postprandial hypothalamic inflammation involving glial fibrillary acidic protein-positive cells and microglia in male mice. Glia 2020; 69:42-60. [PMID: 32659044 DOI: 10.1002/glia.23882] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 06/10/2020] [Accepted: 06/11/2020] [Indexed: 12/15/2022]
Abstract
In humans, obesity is associated with brain inflammation, glial reactivity, and immune cells infiltration. Studies in rodents have shown that glial reactivity occurs within 24 hr of high-fat diet (HFD) consumption, long before obesity development, and takes place mainly in the hypothalamus (HT), a crucial brain structure for controlling body weight. Here, we sought to characterize the postprandial HT inflammatory response to 1, 3, and 6 hr of exposure to either a standard diet (SD) or HFD. HFD exposure increased gene expression of astrocyte and microglial markers (glial fibrillary acidic protein [GFAP] and Iba1, respectively) compared to SD-treated mice and induced morphological modifications of microglial cells in HT. This remodeling was associated with higher expression of inflammatory genes and differential regulation of hypothalamic neuropeptides involved in energy balance regulation. DREADD and PLX5622 technologies, used to modulate GFAP-positive or microglial cells activity, respectively, showed that both glial cell types are involved in hypothalamic postprandial inflammation, with their own specific kinetics and reactiveness to ingested foods. Thus, recurrent exacerbated postprandial inflammation in the brain might promote obesity and needs to be characterized to address this worldwide crisis.
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Affiliation(s)
- Céline Cansell
- IPMC, CNRS, Université Côte d'Azur, IPMC, CNRS, Valbonne, France
| | - Katharina Stobbe
- IPMC, CNRS, Université Côte d'Azur, IPMC, CNRS, Valbonne, France
| | - Clara Sanchez
- IPMC, CNRS, Université Côte d'Azur, IPMC, CNRS, Valbonne, France
| | - Ophélia Le Thuc
- IPMC, CNRS, Université Côte d'Azur, IPMC, CNRS, Valbonne, France
| | - Coralie-Anne Mosser
- Laboratory of Neurophysiology and New Microscopies, INSERM, Université Paris Descartes, Paris, France
| | - Selma Ben-Fradj
- CSGA, AgroSup Dijon, CNRS, INRA, Université Bourgogne Franche-Comté, Dijon, France
| | - Joris Leredde
- IPMC, CNRS, Université Côte d'Azur, IPMC, CNRS, Valbonne, France
| | | | - Delphine Debayle
- IPMC, CNRS, Université Côte d'Azur, IPMC, CNRS, Valbonne, France
| | - Lucile Fleuriot
- IPMC, CNRS, Université Côte d'Azur, IPMC, CNRS, Valbonne, France
| | - Frédéric Brau
- IPMC, CNRS, Université Côte d'Azur, IPMC, CNRS, Valbonne, France
| | - Nadège Devaux
- IPMC, CNRS, Université Côte d'Azur, IPMC, CNRS, Valbonne, France
| | - Alexandre Benani
- CSGA, AgroSup Dijon, CNRS, INRA, Université Bourgogne Franche-Comté, Dijon, France
| | - Etienne Audinat
- IGF, CNRS, INSERM, Université de Montpellier, Montpellier, France
| | - Nicolas Blondeau
- IPMC, CNRS, Université Côte d'Azur, IPMC, CNRS, Valbonne, France
| | - Jean-Louis Nahon
- IPMC, CNRS, Université Côte d'Azur, IPMC, CNRS, Valbonne, France
| | - Carole Rovère
- IPMC, CNRS, Université Côte d'Azur, IPMC, CNRS, Valbonne, France
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40
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Johnson LA. APOE and metabolic dysfunction in Alzheimer's disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2020; 154:131-151. [PMID: 32739002 DOI: 10.1016/bs.irn.2020.02.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The strongest genetic risk factor for sporadic Alzheimer's disease (AD) is carriage of the E4 allele of APOE. Metabolic dysfunction also increases risk of dementia and AD. Facing a need for effective therapies and an aging global population, studies aimed at uncovering new therapeutic targets for AD have become critical. Insight into the biology underlying the effects of E4 and metabolic impairment on the brain may lead to novel therapies to reduce AD risk. An understudied hallmark of both AD patients and E4 individuals is a common metabolic impairment-cerebral glucose hypometabolism. This is a robust and replicated finding in humans, and begins decades prior to cognitive decline. Possession of E4 also appears to alter several other aspects of cerebral glucose metabolism, fatty acid metabolism, and management of oxidative stress through the pentose phosphate pathway. A critical knowledge gap in AD is the mechanism by which APOE alters cerebral metabolism and clarification as to its relevance to AD risk. Facing a need for effective therapies, studies aimed at uncovering new therapeutic targets have become critical. One such approach is to gain a better understanding of the metabolic mechanisms that may underlie E4-associated cognitive dysfunction and AD risk.
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Affiliation(s)
- Lance A Johnson
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, United States; Sanders-Brown Center on Aging, University of Kentucky College of Medicine, Lexington, KY, United States.
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41
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Timper K, Del Río-Martín A, Cremer AL, Bremser S, Alber J, Giavalisco P, Varela L, Heilinger C, Nolte H, Trifunovic A, Horvath TL, Kloppenburg P, Backes H, Brüning JC. GLP-1 Receptor Signaling in Astrocytes Regulates Fatty Acid Oxidation, Mitochondrial Integrity, and Function. Cell Metab 2020; 31:1189-1205.e13. [PMID: 32433922 PMCID: PMC7272126 DOI: 10.1016/j.cmet.2020.05.001] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 12/09/2019] [Accepted: 05/02/2020] [Indexed: 02/06/2023]
Abstract
Astrocytes represent central regulators of brain glucose metabolism and neuronal function. They have recently been shown to adapt their function in response to alterations in nutritional state through responding to the energy state-sensing hormones leptin and insulin. Here, we demonstrate that glucagon-like peptide (GLP)-1 inhibits glucose uptake and promotes β-oxidation in cultured astrocytes. Conversely, postnatal GLP-1 receptor (GLP-1R) deletion in glial fibrillary acidic protein (GFAP)-expressing astrocytes impairs astrocyte mitochondrial integrity and activates an integrated stress response with enhanced fibroblast growth factor (FGF)21 production and increased brain glucose uptake. Accordingly, central neutralization of FGF21 or astrocyte-specific FGF21 inactivation abrogates the improvements in glucose tolerance and learning in mice lacking GLP-1R expression in astrocytes. Collectively, these experiments reveal a role for astrocyte GLP-1R signaling in maintaining mitochondrial integrity, and lack of GLP-1R signaling mounts an adaptive stress response resulting in an improvement of systemic glucose homeostasis and memory formation.
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Affiliation(s)
- Katharina Timper
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Almudena Del Río-Martín
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Anna Lena Cremer
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany
| | - Stephan Bremser
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany; Institute for Zoology, Biocenter, University of Cologne, Zuelpicher Str. 47B, 50674 Cologne, Germany
| | - Jens Alber
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Patrick Giavalisco
- Max Planck Institute for Biology of Aging, Joseph-Stelzmann-Str. 9b, 50931 Cologne, Germany
| | - Luis Varela
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Christian Heilinger
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Hendrik Nolte
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Aleksandra Trifunovic
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany; Institute for Mitochondrial Diseases and Aging, Medical Faculty, University of Cologne, 50931 Cologne, Germany
| | - Tamas L Horvath
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Anatomy and Histology, University of Veterinary Medicine, 1078 Budapest, Hungary
| | - Peter Kloppenburg
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany; Institute for Zoology, Biocenter, University of Cologne, Zuelpicher Str. 47B, 50674 Cologne, Germany
| | - Heiko Backes
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany
| | - Jens C Brüning
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany; National Center for Diabetes Research (DZD), Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
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42
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Morris G, Puri BK, Walker AJ, Maes M, Carvalho AF, Bortolasci CC, Walder K, Berk M. Shared pathways for neuroprogression and somatoprogression in neuropsychiatric disorders. Neurosci Biobehav Rev 2019; 107:862-882. [PMID: 31545987 DOI: 10.1016/j.neubiorev.2019.09.025] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 08/13/2019] [Accepted: 09/16/2019] [Indexed: 12/13/2022]
Abstract
Activated immune-inflammatory, oxidative and nitrosative stress (IO&NS) pathways and consequent mitochondrial aberrations are involved in the pathophysiology of psychiatric disorders including major depression, bipolar disorder and schizophrenia. They offer independent and shared contributions to pathways underpinning medical comorbidities including insulin resistance, metabolic syndrome, obesity and cardiovascular disease - herein conceptualized as somatoprogression. This narrative review of human studies aims to summarize relationships between IO&NS pathways, neuroprogression and somatoprogression. Activated IO&NS pathways, implicated in the neuroprogression of psychiatric disorders, affect the pathogenesis of comorbidities including insulin resistance, dyslipidaemia, obesity and hypertension, and by inference, metabolic syndrome. These conditions activate IO&NS pathways, exacerbating neuroprogression in psychiatric disorders. The processes whereby proinflammatory cytokines, nitrosative and endoplasmic reticulum stress, NADPH oxidase isoforms, PPARγ inactivation, SIRT1 deficiency and intracellular signalling pathways impact lipid metabolism and storage are considered. Through associations between body mass index, chronic neuroinflammation and FTO expression, activation of IO&NS pathways arising from somatoprogression may contribute to neuroprogression. Early evidence highlights the potential of adjuvants targeting IO&NS pathways for treating somatoprogression and neuroprogression.
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Affiliation(s)
- Gerwyn Morris
- Deakin University, IMPACT Strategic Research Centre, Barwon Health, School of Medicine, Geelong, Victoria, Australia
| | - Basant K Puri
- Department of Medicine, Hammersmith Hospital, Imperial College London, London, UK
| | - Adam J Walker
- Deakin University, IMPACT Strategic Research Centre, Barwon Health, School of Medicine, Geelong, Victoria, Australia
| | - Michael Maes
- Deakin University, IMPACT Strategic Research Centre, Barwon Health, School of Medicine, Geelong, Victoria, Australia
| | - Andre F Carvalho
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada; Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada
| | - Chiara C Bortolasci
- Deakin University, CMMR Strategic Research Centre, School of Medicine, Geelong, Victoria, Australia
| | - Ken Walder
- Deakin University, CMMR Strategic Research Centre, School of Medicine, Geelong, Victoria, Australia
| | - Michael Berk
- Deakin University, IMPACT Strategic Research Centre, Barwon Health, School of Medicine, Geelong, Victoria, Australia; Deakin University, CMMR Strategic Research Centre, School of Medicine, Geelong, Victoria, Australia; Orygen, The National Centre of Excellence in Youth Mental Health, the Department of Psychiatry and the Florey Institute for Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia.
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Le Foll C. Hypothalamic Fatty Acids and Ketone Bodies Sensing and Role of FAT/CD36 in the Regulation of Food Intake. Front Physiol 2019; 10:1036. [PMID: 31474875 PMCID: PMC6702519 DOI: 10.3389/fphys.2019.01036] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 07/29/2019] [Indexed: 12/19/2022] Open
Abstract
The obesity and type-2 diabetes epidemic is escalating and represents one of the costliest biomedical challenges confronting modern society. Moreover, the increasing consumption of high fat food is often correlated with an increase in body mass index. In people predisposed to be obese or already obese, the impaired ability of the brain to monitor and respond to alterations in fatty acid (FA) metabolism is increasingly recognized as playing a role in the pathophysiological development of these disorders. The brain senses and regulates metabolism using highly specialized nutrient-sensing neurons located mainly in the hypothalamus. The same neurons are able to detect variation in the extracellular levels of glucose, FA and ketone bodies as a way to monitor nutrient availability and to alter its own activity. In addition, glial cells such as astrocytes create major connections to neurons and form a tight relationship to closely regulate nutrient uptake and metabolism. This review will examine the different pathways by which neurons are able to detect free fatty acids (FFA) to alter its activity and how high fat diet (HFD)-astrocytes induced ketone bodies production interplays with neuronal FA sensing. The role of HFD-induced inflammation and how FA modulate the reward system will also be investigated here.
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Affiliation(s)
- Christelle Le Foll
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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Chudoba C, Wardelmann K, Kleinridders A. Molecular effects of dietary fatty acids on brain insulin action and mitochondrial function. Biol Chem 2019; 400:991-1003. [PMID: 30730834 DOI: 10.1515/hsz-2018-0477] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Accepted: 01/28/2019] [Indexed: 01/17/2023]
Abstract
The prevalence of obesity and its co-morbidities such as insulin resistance and type 2 diabetes are tightly linked to increased ingestion of palatable fat enriched food. Thus, it seems intuitive that the brain senses elevated amounts of fatty acids (FAs) and affects adaptive metabolic response, which is connected to mitochondrial function and insulin signaling. This review will address the effect of dietary FAs on brain insulin and mitochondrial function with a special emphasis on the impact of different FAs on brain function and metabolism.
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Affiliation(s)
- Chantal Chudoba
- Central Regulation of Metabolism, German Institute of Human Nutrition (DIfE), Arthur-Scheunert-Allee 114-116, D-14558 Nuthetal, Germany.,German Center for Diabetes Research (DZD), Ingolstädter Landstraße 1, D-85764 Neuherberg, Germany
| | - Kristina Wardelmann
- Central Regulation of Metabolism, German Institute of Human Nutrition (DIfE), Arthur-Scheunert-Allee 114-116, D-14558 Nuthetal, Germany.,German Center for Diabetes Research (DZD), Ingolstädter Landstraße 1, D-85764 Neuherberg, Germany
| | - André Kleinridders
- Central Regulation of Metabolism, German Institute of Human Nutrition (DIfE), Arthur-Scheunert-Allee 114-116, D-14558 Nuthetal, Germany.,German Center for Diabetes Research (DZD), Ingolstädter Landstraße 1, D-85764 Neuherberg, Germany
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Abstract
Under conditions leading to aging and metabolic syndrome, the hypothalamus atypically undergoes proinflammatory signaling activation leading to a chronic and stable background inflammation, referred to as "hypothalamic microinflammation." Through the past decade of research, progress has been made to causally link this hypothalamic inflammation to the mechanism of aging as well as metabolic syndrome, promoting the "hypothalamic microinflammation" theory, which helps characterize the consensus of these epidemic health problems. In general, it is consistently appreciated that hypothalamic microinflammation emerges during the early stages of aging and metabolic syndrome and evolves to be multifaceted and advanced alongside disease progression, while inhibition of key inflammatory components in the hypothalamus has a broad range of effects in counteracting these disorders. Herein, focusing on aging and metabolic syndrome, this writing aims to provide an overview of and insights into the mediators, signaling components, cellular impacts, and physiological significance of this hypothalamic microinflammation.
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Chowen JA, Frago LM, Fernández-Alfonso MS. Physiological and pathophysiological roles of hypothalamic astrocytes in metabolism. J Neuroendocrinol 2019; 31:e12671. [PMID: 30561077 DOI: 10.1111/jne.12671] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 11/27/2018] [Accepted: 12/11/2018] [Indexed: 12/26/2022]
Abstract
The role of glial cells, including astrocytes, in metabolic control has received increasing attention in recent years. Although the original interest in these macroglial cells was a result of astrogliosis being observed in the hypothalamus of diet-induced obese subjects, studies have also focused on how they participate in the physiological control of appetite and energy expenditure. Astrocytes express receptors for numerous hormones, growth factors and neuropeptides. Some functions of astrocytes include transport of nutrients and hormones from the circulation to the brain, storage of glycogen, participation in glucose sensing, synaptic plasticity, uptake and metabolism of neurotransmitters, release of substances to modify neurotransmission, and cytokine production, amongst others. In the hypothalamus, these physiological glial functions impact on neuronal circuits that control systemic metabolism to modify their outputs. The initial response of astrocytes to poor dietary habits and obesity involves activation of neuroprotective mechanisms but, with chronic exposure to these situations, hypothalamic astrocytes participate in the development of some of the damaging secondary effects. The present review discusses not only some of the physiological functions of hypothalamic astrocytes in metabolism, but also their role in the secondary complications of obesity, such as insulin resistance and cardiovascular affectations.
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Affiliation(s)
- Julie A Chowen
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Madrid, Spain
- CIBEROBN (Centro de Investigación Biomédica en Red sobre Fisiopatología de la Obesidad y Nutrición), Instituto de Salud Carlos III, Madrid, Spain
- IMDEA Food Institute, CEI UAM + CSIC, Madrid, Spain
| | - Laura M Frago
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Madrid, Spain
- CIBEROBN (Centro de Investigación Biomédica en Red sobre Fisiopatología de la Obesidad y Nutrición), Instituto de Salud Carlos III, Madrid, Spain
- Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, Spain
| | - María Soledad Fernández-Alfonso
- Instituto Pluridisciplinar UCM y Departamento de Farmacología, Farmacognosia y Botánica, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
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Abbink MR, van Deijk ALF, Heine VM, Verheijen MH, Korosi A. The involvement of astrocytes in early-life adversity induced programming of the brain. Glia 2019; 67:1637-1653. [PMID: 31038797 PMCID: PMC6767561 DOI: 10.1002/glia.23625] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 03/29/2019] [Accepted: 03/29/2019] [Indexed: 12/13/2022]
Abstract
Early‐life adversity (ELA) in the form of stress, inflammation, or malnutrition, can increase the risk of developing psychopathology or cognitive problems in adulthood. The neurobiological substrates underlying this process remain unclear. While neuronal dysfunction and microglial contribution have been studied in this context, only recently the role of astrocytes in early‐life programming of the brain has been appreciated. Astrocytes serve many basic roles for brain functioning (e.g., synaptogenesis, glutamate recycling), and are unique in their capacity of sensing and integrating environmental signals, as they are the first cells to encounter signals from the blood, including hormonal changes (e.g., glucocorticoids), immune signals, and nutritional information. Integration of these signals is especially important during early development, and therefore we propose that astrocytes contribute to ELA induced changes in the brain by sensing and integrating environmental signals and by modulating neuronal development and function. Studies in rodents have already shown that ELA can impact astrocytes on the short and long term, however, a critical review of these results is currently lacking. Here, we will discuss the developmental trajectory of astrocytes, their ability to integrate stress, immune, and nutritional signals from the early environment, and we will review how different types of early adversity impact astrocytes.
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Affiliation(s)
- Maralinde R Abbink
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Anne-Lieke F van Deijk
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit, Amsterdam, The Netherlands
| | - Vivi M Heine
- Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit, Amsterdam, The Netherlands
| | - Mark H Verheijen
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit, Amsterdam, The Netherlands
| | - Aniko Korosi
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
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Bouyakdan K, Martin H, Liénard F, Budry L, Taib B, Rodaros D, Chrétien C, Biron É, Husson Z, Cota D, Pénicaud L, Fulton S, Fioramonti X, Alquier T. The gliotransmitter ACBP controls feeding and energy homeostasis via the melanocortin system. J Clin Invest 2019; 129:2417-2430. [PMID: 30938715 PMCID: PMC6546475 DOI: 10.1172/jci123454] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Glial cells have emerged as key players in the central control of energy balance and etiology of obesity. Astrocytes play a central role in neural communication via the release of gliotransmitters. Acyl-CoA binding protein (ACBP)-derived endozepines are secreted peptides that modulate the GABAA receptor. In the hypothalamus, ACBP is enriched in arcuate nucleus (ARC) astrocytes, ependymocytes and tanycytes. Central administration of the endozepine octadecaneuropeptide (ODN) reduces feeding and improves glucose tolerance, yet the contribution of endogenous ACBP in energy homeostasis is unknown. We demonstrated that ACBP deletion in GFAP+ astrocytes, but not in Nkx2.1-lineage neural cells, promoted diet-induced hyperphagia and obesity in both male and female mice, an effect prevented by viral rescue of ACBP in ARC astrocytes. ACBP-astrocytes were observed in apposition with proopiomelanocortin (POMC) neurons and ODN selectively activated POMC neurons through the ODN-GPCR but not GABAA, and supressed feeding while increasing carbohydrate utilization via the melanocortin system. Similarly, ACBP overexpression in ARC astrocytes reduced feeding and weight gain. Finally, the ODN-GPCR agonist decreased feeding and promoted weight loss in ob/ob mice. These findings uncover ACBP as an ARC gliopeptide playing a key role in energy balance control and exerting strong anorectic effects via the central melanocortin system.
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Affiliation(s)
- Khalil Bouyakdan
- Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine, Pathology and Cell Biology, Biochemistry, Neurosciences, and Nutrition, Université de Montréal, Montreal, Quebec, Canada
| | - Hugo Martin
- Université de Bordeaux, INRA, NutriNeuro, Bordeaux, France
- Bordeaux INP, NutriNeuro, Talence, France
| | - Fabienne Liénard
- Centre des Sciences du Goût et de l’Alimentation, UMR 6265 CNRS, 1324 INRA, Université de Bourgogne Franche-Comté, Dijon, France
| | - Lionel Budry
- Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine, Pathology and Cell Biology, Biochemistry, Neurosciences, and Nutrition, Université de Montréal, Montreal, Quebec, Canada
| | - Bouchra Taib
- Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine, Pathology and Cell Biology, Biochemistry, Neurosciences, and Nutrition, Université de Montréal, Montreal, Quebec, Canada
| | - Demetra Rodaros
- Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine, Pathology and Cell Biology, Biochemistry, Neurosciences, and Nutrition, Université de Montréal, Montreal, Quebec, Canada
| | - Chloé Chrétien
- Centre des Sciences du Goût et de l’Alimentation, UMR 6265 CNRS, 1324 INRA, Université de Bourgogne Franche-Comté, Dijon, France
| | - Éric Biron
- Faculty of Pharmacy, Université Laval and Laboratory of Medicinal Chemistry, Centre de Recherche du Centre Hospitalier Universitaire de Québec (CRCHUQ), Quebec, Quebec, Canada
| | - Zoé Husson
- Université de Bordeaux, INRA, NutriNeuro, Bordeaux, France
- Bordeaux INP, NutriNeuro, Talence, France
- INSERM, Université de Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, Bordeaux, France
| | - Daniela Cota
- INSERM, Université de Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, Bordeaux, France
| | - Luc Pénicaud
- Centre des Sciences du Goût et de l’Alimentation, UMR 6265 CNRS, 1324 INRA, Université de Bourgogne Franche-Comté, Dijon, France
- Stromalab, CNRS ERL 5311, Université de Toulouse, Université Paul Sabatier, Toulouse, France
| | - Stephanie Fulton
- Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine, Pathology and Cell Biology, Biochemistry, Neurosciences, and Nutrition, Université de Montréal, Montreal, Quebec, Canada
| | - Xavier Fioramonti
- Université de Bordeaux, INRA, NutriNeuro, Bordeaux, France
- Bordeaux INP, NutriNeuro, Talence, France
- Centre des Sciences du Goût et de l’Alimentation, UMR 6265 CNRS, 1324 INRA, Université de Bourgogne Franche-Comté, Dijon, France
| | - Thierry Alquier
- Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Montreal Diabetes Research Center, and Departments of Medicine, Pathology and Cell Biology, Biochemistry, Neurosciences, and Nutrition, Université de Montréal, Montreal, Quebec, Canada
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Role of astrocytes, microglia, and tanycytes in brain control of systemic metabolism. Nat Neurosci 2018; 22:7-14. [PMID: 30531847 DOI: 10.1038/s41593-018-0286-y] [Citation(s) in RCA: 166] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 11/06/2018] [Indexed: 12/28/2022]
Abstract
Astrocytes, microglia, and tanycytes play active roles in the regulation of hypothalamic feeding circuits. These non-neuronal cells are crucial in determining the functional interactions of specific neuronal subpopulations involved in the control of metabolism. Recent advances in biology, optics, genetics, and pharmacology have resulted in the emergence of novel and highly sophisticated approaches for studying hypothalamic neuronal-glial networks. Here we summarize the progress in the field and argue that glial-neuronal interactions provide a core hub integrating food-related cues, interoceptive signals, and internal states to adapt a complex set of physiological responses operating on different timescales to finely tune behavior and metabolism according to metabolic status. This expanding knowledge helps to redefine our understanding of the physiology of food intake and energy metabolism.
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p53 in AgRP neurons is required for protection against diet-induced obesity via JNK1. Nat Commun 2018; 9:3432. [PMID: 30143607 PMCID: PMC6109113 DOI: 10.1038/s41467-018-05711-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 07/19/2018] [Indexed: 12/13/2022] Open
Abstract
p53 is a well-known tumor suppressor that has emerged as an important player in energy balance. However, its metabolic role in the hypothalamus remains unknown. Herein, we show that mice lacking p53 in agouti-related peptide (AgRP), but not proopiomelanocortin (POMC) or steroidogenic factor-1 (SF1) neurons, are more prone to develop diet-induced obesity and show reduced brown adipose tissue (BAT) thermogenic activity. AgRP-specific ablation of p53 resulted in increased hypothalamic c-Jun N-terminal kinase (JNK) activity before the mice developed obesity, and central inhibition of JNK reversed the obese phenotype of these mice. The overexpression of p53 in the ARC or specifically in AgRP neurons of obese mice decreased body weight and stimulated BAT thermogenesis, resulting in body weight loss. Finally, p53 in AgRP neurons regulates the ghrelin-induced food intake and body weight. Overall, our findings provide evidence that p53 in AgRP neurons is required for normal adaptations against diet-induced obesity. Emerging studies suggest that p53 is an important regulator of energy metabolism, yet there is little known about the metabolic function of this tumor suppressor in the hypothalamus. Here, authors illustrate that p53, specifically in AgRP neurons, is required for adaptation to diet-induced obesity.
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