1
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Perez-Gianmarco L, Kurt B, Kukley M. Technical approaches and challenges to study AMPA receptors in oligodendrocyte lineage cells: Past, present, and future. Glia 2023; 71:819-847. [PMID: 36453615 DOI: 10.1002/glia.24305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 11/05/2022] [Accepted: 11/10/2022] [Indexed: 12/03/2022]
Abstract
Receptors for α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPARs) are ligand-gated ionotropic receptors for glutamate that is a major excitatory neurotransmitter in the central nervous system. AMPARs are located at postsynaptic sites of neuronal synapses where they mediate fast synaptic signaling and synaptic plasticity. Remarkably, AMPARs are also expressed by glial cells. Their expression by the oligodendrocyte (OL) lineage cells is of special interest because AMPARs mediate fast synaptic communication between neurons and oligodendrocyte progenitor cells (OPCs), modulate proliferation and differentiation of OPCs, and may also be involved in regulation of myelination. On the other hand, during pathological conditions, AMPARs may mediate damage of the OL lineage cells. In the present review, we focus on the technical approaches that have been used to study AMPARs in the OL lineage cells, and discuss future perspectives of AMPAR research in these glial cells.
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Affiliation(s)
- Lucila Perez-Gianmarco
- Laboratory of Neuronal and Glial Physiology, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Department of Neurosciences, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Begüm Kurt
- Laboratory of Neuronal and Glial Physiology, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Department of Neurosciences, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Maria Kukley
- Laboratory of Neuronal and Glial Physiology, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Ikerbasque - Basque Foundation for Science, Bilbao, Spain
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2
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Mey GM, Mahajan KR, DeSilva TM. Neurodegeneration in multiple sclerosis. WIREs Mech Dis 2023; 15:e1583. [PMID: 35948371 PMCID: PMC9839517 DOI: 10.1002/wsbm.1583] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 06/28/2022] [Accepted: 07/11/2022] [Indexed: 01/31/2023]
Abstract
Axonal loss in multiple sclerosis (MS) is a key component of disease progression and permanent neurologic disability. MS is a heterogeneous demyelinating and neurodegenerative disease of the central nervous system (CNS) with varying presentation, disease courses, and prognosis. Immunomodulatory therapies reduce the frequency and severity of inflammatory demyelinating events that are a hallmark of MS, but there is minimal therapy to treat progressive disease and there is no cure. Data from patients with MS, post-mortem histological analysis, and animal models of demyelinating disease have elucidated patterns of MS pathogenesis and underlying mechanisms of neurodegeneration. MRI and molecular biomarkers have been proposed to identify predictors of neurodegeneration and risk factors for disease progression. Early signs of axonal dysfunction have come to light including impaired mitochondrial trafficking, structural axonal changes, and synaptic alterations. With sustained inflammation as well as impaired remyelination, axons succumb to degeneration contributing to CNS atrophy and worsening of disease. These studies highlight the role of chronic demyelination in the CNS in perpetuating axonal loss, and the difficulty in promoting remyelination and repair amidst persistent inflammatory insult. Regenerative and neuroprotective strategies are essential to overcome this barrier, with early intervention being critical to rescue axonal integrity and function. The clinical and basic research studies discussed in this review have set the stage for identifying key propagators of neurodegeneration in MS, leading the way for neuroprotective therapeutic development. This article is categorized under: Immune System Diseases > Molecular and Cellular Physiology Neurological Diseases > Molecular and Cellular Physiology.
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Affiliation(s)
- Gabrielle M. Mey
- Department of NeurosciencesLerner Research Institute, Cleveland Clinic Foundation, and Case Western Reserve UniversityClevelandOhioUSA
| | - Kedar R. Mahajan
- Department of NeurosciencesLerner Research Institute, Cleveland Clinic Foundation, and Case Western Reserve UniversityClevelandOhioUSA
- Mellen Center for MS Treatment and ResearchNeurological Institute, Cleveland Clinic FoundationClevelandOhioUSA
| | - Tara M. DeSilva
- Department of NeurosciencesLerner Research Institute, Cleveland Clinic Foundation, and Case Western Reserve UniversityClevelandOhioUSA
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3
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Evonuk KS, Doyle RE, Moseley CE, Thornell IM, Adler K, Bingaman AM, Bevensee MO, Weaver CT, Min B, DeSilva TM. Reduction of AMPA receptor activity on mature oligodendrocytes attenuates loss of myelinated axons in autoimmune neuroinflammation. SCIENCE ADVANCES 2020; 6:eaax5936. [PMID: 31934627 PMCID: PMC6949032 DOI: 10.1126/sciadv.aax5936] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 11/08/2019] [Indexed: 06/10/2023]
Abstract
Glutamate dysregulation occurs in multiple sclerosis (MS), but whether excitotoxic mechanisms in mature oligodendrocytes contribute to demyelination and axonal injury is unexplored. Although current treatments modulate the immune system, long-term disability ensues, highlighting the need for neuroprotection. Glutamate is elevated before T2-visible white matter lesions appear in MS. We previously reported that myelin-reactive T cells provoke microglia to release glutamate from the system xc - transporter promoting myelin degradation in experimental autoimmune encephalomyelitis (EAE). Here, we explore the target for glutamate in mature oligodendrocytes. Most glutamate-stimulated calcium influx into oligodendrocyte somas is AMPA receptor (AMPAR)-mediated, and genetic deletion of AMPAR subunit GluA4 decreased intracellular calcium responses. Inducible deletion of GluA4 on mature oligodendrocytes attenuated EAE and loss of myelinated axons was selectively reduced compared to unmyelinated axons. These data link AMPAR signaling in mature oligodendrocytes to the pathophysiology of myelinated axons, demonstrating glutamate regulation as a potential neuroprotective strategy in MS.
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Affiliation(s)
- Kirsten S. Evonuk
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Ryan E. Doyle
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Carson E. Moseley
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
- University of California, San Francisco, CA, USA
| | - Ian M. Thornell
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Keith Adler
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Amanda M. Bingaman
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Mark O. Bevensee
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Casey T. Weaver
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Booki Min
- Department of Immunology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Tara M. DeSilva
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
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4
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Ceprian M, Fulton D. Glial Cell AMPA Receptors in Nervous System Health, Injury and Disease. Int J Mol Sci 2019; 20:ijms20102450. [PMID: 31108947 PMCID: PMC6566241 DOI: 10.3390/ijms20102450] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/11/2019] [Accepted: 04/22/2019] [Indexed: 12/16/2022] Open
Abstract
Glia form a central component of the nervous system whose varied activities sustain an environment that is optimised for healthy development and neuronal function. Alpha-amino-3-hydroxy-5-methyl-4-isoxazole (AMPA)-type glutamate receptors (AMPAR) are a central mediator of glutamatergic excitatory synaptic transmission, yet they are also expressed in a wide range of glial cells where they influence a variety of important cellular functions. AMPAR enable glial cells to sense the activity of neighbouring axons and synapses, and as such many aspects of glial cell development and function are influenced by the activity of neural circuits. However, these AMPAR also render glia sensitive to elevations of the extracellular concentration of glutamate, which are associated with a broad range of pathological conditions. Excessive activation of AMPAR under these conditions may induce excitotoxic injury in glial cells, and trigger pathophysiological responses threatening other neural cells and amplifying ongoing disease processes. The aim of this review is to gather information on AMPAR function from across the broad diversity of glial cells, identify their contribution to pathophysiological processes, and highlight new areas of research whose progress may increase our understanding of nervous system dysfunction and disease.
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Affiliation(s)
- Maria Ceprian
- Instituto de Investigación Sanitaria San Carlos (IdISSC), 28040 Madrid, Spain.
- Departamento de Bioquímica y Biología Molecular, CIBERNED, IRICYS. Facultad de Medicina, Universidad Complutense de Madrid, 28040 Madrid, Spain.
| | - Daniel Fulton
- Neuroscience and Ophthalmology Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
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5
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Horiuchi M, Suzuki-Horiuchi Y, Akiyama T, Itoh A, Pleasure D, Carstens E, Itoh T. Differing intrinsic biological properties between forebrain and spinal oligodendroglial lineage cells. J Neurochem 2017; 142:378-391. [PMID: 28512742 DOI: 10.1111/jnc.14074] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 05/11/2017] [Accepted: 05/12/2017] [Indexed: 12/21/2022]
Abstract
Differentiation of oligodendroglial progenitor cells (OPCs) into myelinating oligodendrocytes is known to be regulated by the microenvironment where they differentiate. However, current research has not verified whether or not oligodendroglial lineage cells (OLCs) derived from different anatomical regions of the central nervous system (CNS) respond to microenvironmental cues in the same manner. Here, we isolated pure OPCs from rat neonatal forebrain (FB) and spinal cord (SC) and compared their phenotypes in the same in vitro conditions. We found that although FB and SC OLCs responded differently to the same external factors; they were distinct in proliferation response to mitogens, oligodendrocyte phenotype after differentiation, and cytotoxic responses to α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate-type glutamate receptor-mediated excitotoxicity at immature stages of differentiation in a cell-intrinsic manner. Moreover, transcriptome analysis identified genes differentially expressed between these OPC populations, including those encoding transcription factors (TFs), cell surface molecules, and signaling molecules. Particularly, FB and SC OPCs retained the expression of FB- or SC-specific TFs, such as Foxg1 and Hoxc8, respectively, even after serial passaging in vitro. Given the essential role of these TFs in the regional identities of CNS cells along the rostrocaudal axis, our results suggest that CNS region-specific gene regulation by these TFs may cause cell-intrinsic differences in cellular responses between FB and SC OLCs to extracellular molecules. Further understanding of the regional differences among OPC populations will help to improve treatments for demyelination in different CNS regions and to facilitate the development of stem cell-derived OPCs for cell transplantation therapies for demyelination. Cover Image for this issue: doi. 10.1111/jnc.13809.
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Affiliation(s)
- Makoto Horiuchi
- Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania, USA
| | - Yoko Suzuki-Horiuchi
- Department of Dermatology, Institute of Regenerative Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Tasuku Akiyama
- Temple Itch Center, Department of Dermatology, Department of Anatomy and Cell Biology, Temple University School of Medicine, Philadelphia, Pennsylvania, USA
| | - Aki Itoh
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children Northern California, Sacramento, California, USA.,Department of Neurology, School of Medicine, University of California, Sacramento, California, USA
| | - David Pleasure
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children Northern California, Sacramento, California, USA.,Department of Neurology, School of Medicine, University of California, Sacramento, California, USA
| | - Earl Carstens
- Department of Neurobiology, Physiology & Behavior, University of California, Davis, California, USA
| | - Takayuki Itoh
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children Northern California, Sacramento, California, USA.,Department of Neurology, School of Medicine, University of California, Sacramento, California, USA
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6
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Rajda C, Pukoli D, Bende Z, Majláth Z, Vécsei L. Excitotoxins, Mitochondrial and Redox Disturbances in Multiple Sclerosis. Int J Mol Sci 2017; 18:ijms18020353. [PMID: 28208701 PMCID: PMC5343888 DOI: 10.3390/ijms18020353] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 01/20/2017] [Accepted: 01/22/2017] [Indexed: 01/03/2023] Open
Abstract
Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS). There is increasing evidence that MS is not only characterized by immune mediated inflammatory reactions, but also by neurodegenerative processes. There is cumulating evidence that neurodegenerative processes, for example mitochondrial dysfunction, oxidative stress, and glutamate (Glu) excitotoxicity, seem to play an important role in the pathogenesis of MS. The alteration of mitochondrial homeostasis leads to the formation of excitotoxins and redox disturbances. Mitochondrial dysfunction (energy disposal failure, apoptosis, etc.), redox disturbances (oxidative stress and enhanced reactive oxygen and nitrogen species production), and excitotoxicity (Glu mediated toxicity) may play an important role in the progression of the disease, causing axonal and neuronal damage. This review focuses on the mechanisms of mitochondrial dysfunction (including mitochondrial DNA (mtDNA) defects and mitochondrial structural/functional changes), oxidative stress (including reactive oxygen and nitric species), and excitotoxicity that are involved in MS and also discusses the potential targets and tools for therapeutic approaches in the future.
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Affiliation(s)
- Cecilia Rajda
- Department of Neurology, University of Szeged, 6725 Szeged, Hungary.
| | - Dániel Pukoli
- Department of Neurology, University of Szeged, 6725 Szeged, Hungary.
- Department of Neurology, Vaszary Kolos Hospital, 2500 Esztergom, Hungary.
| | - Zsuzsanna Bende
- Department of Neurology, University of Szeged, 6725 Szeged, Hungary.
| | - Zsófia Majláth
- Department of Neurology, University of Szeged, 6725 Szeged, Hungary.
| | - László Vécsei
- Department of Neurology, University of Szeged, 6725 Szeged, Hungary.
- MTA-SZTE Neuroscience Research Group, 6725 Szeged, Hungary.
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7
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Macrez R, Stys PK, Vivien D, Lipton SA, Docagne F. Mechanisms of glutamate toxicity in multiple sclerosis: biomarker and therapeutic opportunities. Lancet Neurol 2016; 15:1089-102. [PMID: 27571160 DOI: 10.1016/s1474-4422(16)30165-x] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 06/21/2016] [Accepted: 06/27/2016] [Indexed: 12/22/2022]
Abstract
Research advances support the idea that excessive activation of the glutamatergic pathway plays an important part in the pathophysiology of multiple sclerosis. Beyond the well established direct toxic effects on neurons, additional sites of glutamate-induced cell damage have been described, including effects in oligodendrocytes, astrocytes, endothelial cells, and immune cells. Such toxic effects could provide a link between various pathological aspects of multiple sclerosis, such as axonal damage, oligodendrocyte cell death, demyelination, autoimmunity, and blood-brain barrier dysfunction. Understanding of the mechanisms underlying glutamate toxicity in multiple sclerosis could help in the development of new approaches for diagnosis, treatment, and follow-up in patients with this debilitating disease. While several clinical trials of glutamatergic modulators have had disappointing results, our growing understanding suggests that there is reason to remain optimistic about the therapeutic potential of these drugs.
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Affiliation(s)
| | - Peter K Stys
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Denis Vivien
- INSERM U919, University of Caen Normandy, Caen, France
| | - Stuart A Lipton
- Scintillon Institute San Diego, CA, USA; Scripps Research Institute, La Jolla, CA, USA; School of Mecicine, University of California, San Diego, CA, USA
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8
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Domingues HS, Portugal CC, Socodato R, Relvas JB. Oligodendrocyte, Astrocyte, and Microglia Crosstalk in Myelin Development, Damage, and Repair. Front Cell Dev Biol 2016; 4:71. [PMID: 27551677 PMCID: PMC4923166 DOI: 10.3389/fcell.2016.00071] [Citation(s) in RCA: 208] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 06/15/2016] [Indexed: 01/01/2023] Open
Abstract
Oligodendrocytes are the myelinating glia of the central nervous system. Myelination of axons allows rapid saltatory conduction of nerve impulses and contributes to axonal integrity. Devastating neurological deficits caused by demyelinating diseases, such as multiple sclerosis, illustrate well the importance of the process. In this review, we focus on the positive and negative interactions between oligodendrocytes, astrocytes, and microglia during developmental myelination and remyelination. Even though many lines of evidence support a crucial role for glia crosstalk during these processes, the nature of such interactions is often neglected when designing therapeutics for repair of demyelinated lesions. Understanding the cellular and molecular mechanisms underlying glial cell communication and how they influence oligodendrocyte differentiation and myelination is fundamental to uncover novel therapeutic strategies for myelin repair.
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Affiliation(s)
- Helena S Domingues
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| | - Camila C Portugal
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| | - Renato Socodato
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| | - João B Relvas
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
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9
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Domingues HS, Portugal CC, Socodato R, Relvas JB. Oligodendrocyte, Astrocyte, and Microglia Crosstalk in Myelin Development, Damage, and Repair. Front Cell Dev Biol 2016. [PMID: 27551677 DOI: 10.3389/fcell.2016.00071.ecollection2016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2023] Open
Abstract
Oligodendrocytes are the myelinating glia of the central nervous system. Myelination of axons allows rapid saltatory conduction of nerve impulses and contributes to axonal integrity. Devastating neurological deficits caused by demyelinating diseases, such as multiple sclerosis, illustrate well the importance of the process. In this review, we focus on the positive and negative interactions between oligodendrocytes, astrocytes, and microglia during developmental myelination and remyelination. Even though many lines of evidence support a crucial role for glia crosstalk during these processes, the nature of such interactions is often neglected when designing therapeutics for repair of demyelinated lesions. Understanding the cellular and molecular mechanisms underlying glial cell communication and how they influence oligodendrocyte differentiation and myelination is fundamental to uncover novel therapeutic strategies for myelin repair.
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Affiliation(s)
- Helena S Domingues
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| | - Camila C Portugal
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| | - Renato Socodato
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| | - João B Relvas
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
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10
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Evonuk KS, Baker BJ, Doyle RE, Moseley CE, Sestero CM, Johnston BP, De Sarno P, Tang A, Gembitsky I, Hewett SJ, Weaver CT, Raman C, DeSilva TM. Inhibition of System Xc(-) Transporter Attenuates Autoimmune Inflammatory Demyelination. THE JOURNAL OF IMMUNOLOGY 2015; 195:450-463. [PMID: 26071560 DOI: 10.4049/jimmunol.1401108] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 05/11/2015] [Indexed: 01/15/2023]
Abstract
T cell infiltration into the CNS is a significant underlying pathogenesis in autoimmune inflammatory demyelinating diseases. Several lines of evidence suggest that glutamate dysregulation in the CNS is an important consequence of immune cell infiltration in neuroinflammatory demyelinating diseases; yet, the causal link between inflammation and glutamate dysregulation is not well understood. A major source of glutamate release during oxidative stress is the system Xc(-) transporter; however, this mechanism has not been tested in animal models of autoimmune inflammatory demyelination. We find that pharmacological and genetic inhibition of system Xc(-) attenuates chronic and relapsing-remitting experimental autoimmune encephalomyelitis (EAE). Remarkably, pharmacological blockade of system Xc(-) 7 d after induction of EAE attenuated T cell infiltration into the CNS, but not T cell activation in the periphery. Mice harboring a Slc7a11 (xCT) mutation that inactivated system Xc(-) were resistant to EAE, corroborating a central role for system Xc(-) in mediating immune cell infiltration. We next examined the role of the system Xc(-) transporter in the CNS after immune cell infiltration. Pharmacological inhibitors of the system Xc(-) transporter administered during the first relapse in a SJL animal model of relapsing-remitting EAE abrogated clinical disease, inflammation, and myelin loss. Primary coculture studies demonstrate that myelin-specific CD4(+) Th1 cells provoke microglia to release glutamate via the system Xc(-) transporter, causing excitotoxic death to mature myelin-producing oligodendrocytes. Taken together, these studies support a novel role for the system Xc(-) transporter in mediating T cell infiltration into the CNS as well as promoting myelin destruction after immune cell infiltration in EAE.
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Affiliation(s)
- Kirsten S Evonuk
- Center for Glial Biology in Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Brandi J Baker
- Center for Glial Biology in Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Ryan E Doyle
- Center for Glial Biology in Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Carson E Moseley
- Department of Pathology, University of Alabama at Birmingham, AL, 35294
| | - Christine M Sestero
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Biology, Chemistry, and Mathematics, University of Montevallo, Montevallo, AL 35115
| | - Bryce P Johnston
- Center for Glial Biology in Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Patrizia De Sarno
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Andrew Tang
- Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Igor Gembitsky
- Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Sandra J Hewett
- Department of Biology, Program in Neuroscience, Syracuse University, Syracuse, NY, 13244
| | - Casey T Weaver
- Department of Pathology, University of Alabama at Birmingham, AL, 35294
| | - Chander Raman
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Tara M DeSilva
- Center for Glial Biology in Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, 35294
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11
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FGF-2 induces neuronal death through upregulation of system xc-. Brain Res 2013; 1547:25-33. [PMID: 24374066 DOI: 10.1016/j.brainres.2013.12.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 12/03/2013] [Accepted: 12/17/2013] [Indexed: 11/21/2022]
Abstract
The cystine/glutamate antiporter (system xc-) transports cystine into cell in exchange for glutamate. Fibroblast growth factor-2 (FGF-2) upregulates system xc- selectively on astrocytes, which leads to increased cystine uptake, the substrate for glutathione production, and increased glutamate release. While increased intracellular glutathione can limit oxidative stress, the increased glutamate release can potentially lead to excitotoxicity to neurons. To test this hypothesis, mixed neuronal and glial cortical cultures were treated with FGF-2. Treatment with FGF-2 for 48 h caused a significant neuronal death in these cultures. Cell death was not observed in neuronal-enriched cultures, or astrocyte-enriched cultures, suggesting the toxicity was the result of neuron-glia interaction. Blocking system xc- eliminated the neuronal death as did the AMPA/kainate receptor antagonist 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo[f]quinoxaline-2,3-dione (NBQX), but not the NMDA receptor antagonist memantine. When cultures were exposed directly to glutamate, both NBQX and memantine blocked the neuronal toxicity. The mechanism of this altered profile of glutamate receptor mediated toxicity by FGF-2 is unclear. The selective calcium permeable AMPA receptor antagonist 1-naphthyl acetyl spermine (NASPM) failed to offer protection. The most likely explanation for the results is that 48 h FGF-2 treatment induces AMPA/kainate receptor toxicity through increased system xc- function resulting in increased release of glutamate. At the same time, FGF-2 alters the sensitivity of the neurons to glutamate toxicity in a manner that promotes selective AMPA/kainate receptor mediated toxicity.
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12
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Moreno M, Guo F, Mills Ko E, Bannerman P, Soulika A, Pleasure D. Origins and significance of astrogliosis in the multiple sclerosis model, MOG peptide EAE. J Neurol Sci 2013; 333:55-9. [PMID: 23294494 DOI: 10.1016/j.jns.2012.12.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 12/05/2012] [Accepted: 12/10/2012] [Indexed: 12/31/2022]
Abstract
Astroglia, the most abundant cells in the human CNS, and even more prominent in multiple sclerosis patients, participate in CNS innate and adaptive immunity, and have been hypothesized to play an important role in multiple sclerosis progression. Experimental autoimmune encephalomyelitis elicited in mice by immunization with myelin oligodendrocyte glycoprotein peptide 35-55 provides a means by which to explore the genesis and disease significance of astrogliosis during a chronic immune-mediated CNS inflammatory/demyelinative disorder that, in its' pathological features, strongly resembles multiple sclerosis.
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Affiliation(s)
- Monica Moreno
- Institute for Pediatric Regenerative Research, UC Davis School of Medicine and Shriners Hospitals for Children Northern California, United States
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13
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Molecular pathology, classification, and diagnosis of sporadic human prion disease variants. Folia Neuropathol 2012; 4:AN20110031. [PMID: 22356284 PMCID: PMC3284768 DOI: 10.1042/an20110031] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Glutamate excitotoxicity is a major pathogenic process implicated in many neurodegenerative conditions, including AD (Alzheimer's disease) and following traumatic brain injury. Occurring predominantly from over-stimulation of ionotropic glutamate receptors located along dendrites, excitotoxic axonal degeneration may also occur in white matter tracts. Recent identification of axonal glutamate receptor subunits within axonal nanocomplexes raises the possibility of direct excitotoxic effects on axons. Individual neuronal responses to excitotoxicity are highly dependent on the complement of glutamate receptors expressed by the cell, and the localization of the functional receptors. To enable isolation of distal axons and targeted excitotoxicity, murine cortical neuron cultures were prepared in compartmented microfluidic devices, such that distal axons were isolated from neuronal cell bodies. Within the compartmented culture system, cortical neurons developed to relative maturity at 11 DIV (days in vitro) as demonstrated by the formation of dendritic spines and clustering of the presynaptic protein synaptophysin. The isolated distal axons retained growth cone structures in the absence of synaptic targets, and expressed glutamate receptor subunits. Glutamate treatment (100 μM) to the cell body chamber resulted in widespread degeneration within this chamber and degeneration of distal axons in the other chamber. Glutamate application to the distal axon chamber triggered a lesser degree of axonal degeneration without degenerative changes in the untreated somal chamber. These data indicate that in addition to current mechanisms of indirect axonal excitotoxicity, the distal axon may be a primary target for excitotoxicity in neurodegenerative conditions.
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The AMPA receptor as a therapeutic target: current perspectives and emerging possibilities. Future Med Chem 2010; 2:877-91. [DOI: 10.4155/fmc.10.27] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) is a subtype of the ionotropic glutamate receptors that plays a prominent role in neurotransmission and is widespread throughout the CNS. Because of this, its malfunction can result in a multitude of nervous system diseases. This review looks at compounds that are able to modulate AMPAR function by binding to one of several sites on the receptor that either downregulate its function (competitive, noncompetitive and uncompetitive antagonists) or upregulate its function (positive modulators). It will also give an account of the various diseases that have implicated AMPAR dysfunction and how specific types of AMPAR modulator may be beneficial in their treatment. The AMPAR remains an unexploited but important therapeutic target.
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Steenland HW, Kim SS, Zhuo M. GluR3 subunit regulates sleep, breathing and seizure generation. Eur J Neurosci 2008; 27:1166-73. [PMID: 18312590 DOI: 10.1111/j.1460-9568.2008.06078.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The functional role of GluR3 AMPA (alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid) receptor subunits has remained elusive. In vitro studies of genetic knockout mice have not yielded significant alterations in synaptic communication. However, behavioural approaches utilizing knockout mice have shown that the subunit may be involved in exploration and motor coordination, suggesting that in vivo methodologies may be more forthcoming. We tested the hypothesis that GluR3 subunits are involved in the modulation of neural network activity. We used a freely behaving mouse model to examine the effect of GluR3(-/-) on field potential recordings of electroencephalogram, vital functions (i.e. breathing and heart rate) and muscle tone across natural sleep and wakefulness states. We found that GluR3(-/-) mice virtually lack electroencephalographic signatures of NREM sleep (n = 9) as demonstrated by reduction in electroencephalogram power in the low-frequency bands (delta1, delta2 and theta). In addition, three of nine GluR3(-/-) mice expressed seizure activity during wakefulness and sleep, suggesting that deletion of the GluR3 gene may predispose to seizure. GluR3 gene knockout also produced state-dependent respiratory modulation, with a selective reduction in breathing rate during behavioural inactivity. These findings show that GluR3 subunits have diverse neurophysiological impact, modulating oscillatory networks for sleep, breathing and seizure generation. Finally, this is the first study to demonstrate the feasibility of direct diaphragm electromyogram recordings in freely behaving mice.
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Affiliation(s)
- Hendrik W Steenland
- Department of Physiology, Faculty of Medicine, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, Ontario, Canada M5S 1A8
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