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Uva L, Bruno G, de Curtis M. Activity-dependent extracellular potassium changes in unmyelinated versus myelinated areas in olfactory regions of the isolated female guinea-pig brain. Exp Neurol 2024; 379:114884. [PMID: 38992824 DOI: 10.1016/j.expneurol.2024.114884] [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: 04/15/2024] [Revised: 06/26/2024] [Accepted: 07/08/2024] [Indexed: 07/13/2024]
Abstract
The potassium released in the extracellular space during neuronal activity is rapidly removed by glia and neurons to maintain tissue homeostasis. Oligodendrocyte-derived myelin axonal coating contributes to potassium buffering and is therefore crucial to control brain excitability. We studied activity-dependent extracellular potassium ([K+]o) changes in the piriform cortex (PC), a region that features highly segregated bundles of myelinated and unmyelinated fibers. Four-aminopyridine (4AP; 50 μM) treatment or patterned high-frequency stimulations (hfST) were utilized to generate [K+]o changes measured with potassium-sensitive electrodes in the myelinated lateral olfactory tract (LOT), in the unmyelinated PC layer I and in the myelinated deep PC layers in the ex vivo isolated guinea-pig brain. Seizure-like events induced by 4AP are initiated by the abrupt [K+]o rise in the layer I formed by unmyelinated fibers (Uva et al., 2017). Larger [K+]o shifts occurred in unmyelinated layers compared to the myelinated LOT. LOT hfST that mimicks pre-seizure discharges also generated higher [K+]o changes in unmyelinated PC layer I than in LOT and deep PC layers. The treatment with the Kir4.1 potassium channel blocker BaCl2 (100 μM) enhanced the [K+]o changes generated by hfST in myelinated structures. Our data show that activity-dependent [K+]o changes are intrinsically different in myelinated vs unmyelinated cortical regions. The larger [K+]o shifts generated in unmyelinated structures may represent a vehicle for seizure generation.
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Affiliation(s)
- Laura Uva
- Epilepsy Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11/via Amadeo 42, Milano, Italy..
| | - Gaia Bruno
- Epilepsy Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11/via Amadeo 42, Milano, Italy.; Dipartimento di Biologia e Biotecnologia, via Forlanini, 6, Università di Pavia, 27100, Pavia, Italy..
| | - Marco de Curtis
- Epilepsy Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11/via Amadeo 42, Milano, Italy..
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2
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Peters C, Aberle T, Sock E, Brunner J, Küspert M, Hillgärtner S, Wüst HM, Wegner M. Voltage-Gated Ion Channels Are Transcriptional Targets of Sox10 during Oligodendrocyte Development. Cells 2024; 13:1159. [PMID: 38995010 PMCID: PMC11240802 DOI: 10.3390/cells13131159] [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: 06/17/2024] [Revised: 07/02/2024] [Accepted: 07/04/2024] [Indexed: 07/13/2024] Open
Abstract
The transcription factor Sox10 is an important determinant of oligodendroglial identity and influences oligodendroglial development and characteristics at various stages. Starting from RNA-seq data, we here show that the expression of several voltage-gated ion channels with known expression and important function in oligodendroglial cells depends upon Sox10. These include the Nav1.1, Cav2.2, Kv1.1, and Kir4.1 channels. For each of the four encoding genes, we found at least one regulatory region that is activated by Sox10 in vitro and at the same time bound by Sox10 in vivo. Cell-specific deletion of Sox10 in oligodendroglial cells furthermore led to a strong downregulation of all four ion channels in a mouse model and thus in vivo. Our study provides a clear functional link between voltage-gated ion channels and the transcriptional regulatory network in oligodendroglial cells. Furthermore, our study argues that Sox10 exerts at least some of its functions in oligodendrocyte progenitor cells, in myelinating oligodendrocytes, or throughout lineage development via these ion channels. By doing so, we present one way in which oligodendroglial development and properties can be linked to neuronal activity to ensure crosstalk between cell types during the development and function of the central nervous system.
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Affiliation(s)
- Christian Peters
- Institut für Biochemie, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Tim Aberle
- Institut für Biochemie, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Elisabeth Sock
- Institut für Biochemie, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Jessica Brunner
- Institut für Biochemie, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Melanie Küspert
- Institut für Biochemie, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Simone Hillgärtner
- Institut für Biochemie, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Hannah M Wüst
- Institut für Biochemie, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Michael Wegner
- Institut für Biochemie, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
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3
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Fletcher JL, Young KM. Do oligodendrocytes regulate axonal glucose uptake and consumption? Trends Neurosci 2024:S0166-2236(24)00115-2. [PMID: 38866601 DOI: 10.1016/j.tins.2024.06.001] [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: 05/24/2024] [Accepted: 06/04/2024] [Indexed: 06/14/2024]
Abstract
Neurons have high energy demands. In a recent study, Looser et al. identified oligodendrocyte Kir4.1 as the activity-dependent driver of oligodendrocyte glycolysis that ensures that lactate is supplied to active neurons. Given that oligodendrocyte Kir4.1 also influenced axonal glucose consumption and uptake, oligodendrocytes may play a broader role in neuronal metabolic regulation.
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Affiliation(s)
- Jessica L Fletcher
- Menzies Institute for Medical Research, University of Tasmania, 17 Liverpool St, Hobart, TAS 7000, Australia
| | - Kaylene M Young
- Menzies Institute for Medical Research, University of Tasmania, 17 Liverpool St, Hobart, TAS 7000, Australia.
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4
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Osso LA, Hughes EG. Dynamics of mature myelin. Nat Neurosci 2024:10.1038/s41593-024-01642-2. [PMID: 38773349 DOI: 10.1038/s41593-024-01642-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 04/05/2024] [Indexed: 05/23/2024]
Abstract
Myelin, which is produced by oligodendrocytes, insulates axons to facilitate rapid and efficient action potential propagation in the central nervous system. Traditionally viewed as a stable structure, myelin is now known to undergo dynamic modulation throughout life. This Review examines these dynamics, focusing on two key aspects: (1) the turnover of myelin, involving not only the renewal of constituents but the continuous wholesale replacement of myelin membranes; and (2) the structural remodeling of pre-existing, mature myelin, a newly discovered form of neural plasticity that can be stimulated by external factors, including neuronal activity, behavioral experience and injury. We explore the mechanisms regulating these dynamics and speculate that myelin remodeling could be driven by an asymmetry in myelin turnover or reactivation of pathways involved in myelin formation. Finally, we outline how myelin remodeling could have profound impacts on neural function, serving as an integral component of behavioral adaptation.
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Affiliation(s)
- Lindsay A Osso
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Ethan G Hughes
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA.
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5
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Jamet M, Dupuis L, Gonzalez De Aguilar JL. Oligodendrocytes in amyotrophic lateral sclerosis and frontotemporal dementia: the new players on stage. Front Mol Neurosci 2024; 17:1375330. [PMID: 38585368 PMCID: PMC10995329 DOI: 10.3389/fnmol.2024.1375330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 03/05/2024] [Indexed: 04/09/2024] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are fatal adult-onset neurodegenerative disorders that share clinical, neuropathological and genetic features, which forms part of a multi-system disease spectrum. The pathological process leading to ALS and FTD is the result of the combination of multiple mechanisms that operate within specific populations of neurons and glial cells. The implication of oligodendrocytes has been the subject of a number of studies conducted on patients and related animal models. In this review we summarize our current knowledge on the alterations specific to myelin and the oligodendrocyte lineage occurring in ALS and FTD. We also consider different ways by which specific oligodendroglial alterations influence neurodegeneration and highlight the important role of oligodendrocytes in these two intrinsically associated neurodegenerative diseases.
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Affiliation(s)
| | | | - Jose-Luis Gonzalez De Aguilar
- Strasbourg Translational Neuroscience and Psychiatry, Institut National de la Santé et de la Recherche Médicale, Université de Strasbourg, Strasbourg, France
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6
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Looser ZJ, Faik Z, Ravotto L, Zanker HS, Jung RB, Werner HB, Ruhwedel T, Möbius W, Bergles DE, Barros LF, Nave KA, Weber B, Saab AS. Oligodendrocyte-axon metabolic coupling is mediated by extracellular K + and maintains axonal health. Nat Neurosci 2024; 27:433-448. [PMID: 38267524 PMCID: PMC10917689 DOI: 10.1038/s41593-023-01558-3] [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: 11/08/2022] [Accepted: 12/13/2023] [Indexed: 01/26/2024]
Abstract
The integrity of myelinated axons relies on homeostatic support from oligodendrocytes (OLs). To determine how OLs detect axonal spiking and how rapid axon-OL metabolic coupling is regulated in the white matter, we studied activity-dependent calcium (Ca2+) and metabolite fluxes in the mouse optic nerve. We show that fast axonal spiking triggers Ca2+ signaling and glycolysis in OLs. OLs detect axonal activity through increases in extracellular potassium (K+) concentrations and activation of Kir4.1 channels, thereby regulating metabolite supply to axons. Both pharmacological inhibition and OL-specific inactivation of Kir4.1 reduce the activity-induced axonal lactate surge. Mice lacking oligodendroglial Kir4.1 exhibit lower resting lactate levels and altered glucose metabolism in axons. These early deficits in axonal energy metabolism are associated with late-onset axonopathy. Our findings reveal that OLs detect fast axonal spiking through K+ signaling, making acute metabolic coupling possible and adjusting the axon-OL metabolic unit to promote axonal health.
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Affiliation(s)
- Zoe J Looser
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
- Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland
| | - Zainab Faik
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
- Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland
| | - Luca Ravotto
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
- Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland
| | - Henri S Zanker
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
- Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland
| | - Ramona B Jung
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Hauke B Werner
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Torben Ruhwedel
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Wiebke Möbius
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Dwight E Bergles
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University, Baltimore, MD, USA
| | - L Felipe Barros
- Centro de Estudios Científicos (CECs), Valdivia, Chile
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Valdivia, Chile
| | - Klaus-Armin Nave
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Bruno Weber
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
- Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland
| | - Aiman S Saab
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland.
- Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland.
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7
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Janeckova L, Knotek T, Kriska J, Hermanova Z, Kirdajova D, Kubovciak J, Berkova L, Tureckova J, Camacho Garcia S, Galuskova K, Kolar M, Anderova M, Korinek V. Astrocyte-like subpopulation of NG2 glia in the adult mouse cortex exhibits characteristics of neural progenitor cells. Glia 2024; 72:245-273. [PMID: 37772368 DOI: 10.1002/glia.24471] [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: 02/20/2023] [Revised: 09/05/2023] [Accepted: 09/05/2023] [Indexed: 09/30/2023]
Abstract
Glial cells expressing neuron-glial antigen 2 (NG2), also known as oligodendrocyte progenitor cells (OPCs), play a critical role in maintaining brain health. However, their ability to differentiate after ischemic injury is poorly understood. The aim of this study was to investigate the properties and functions of NG2 glia in the ischemic brain. Using transgenic mice, we selectively labeled NG2-expressing cells and their progeny in both healthy brain and after focal cerebral ischemia (FCI). Using single-cell RNA sequencing, we classified the labeled glial cells into five distinct subpopulations based on their gene expression patterns. Additionally, we examined the membrane properties of these cells using the patch-clamp technique. Of the identified subpopulations, three were identified as OPCs, whereas the fourth subpopulation had characteristics indicative of cells likely to develop into oligodendrocytes. The fifth subpopulation of NG2 glia showed astrocytic markers and had similarities to neural progenitor cells. Interestingly, this subpopulation was present in both healthy and post-ischemic tissue; however, its gene expression profile changed after ischemia, with increased numbers of genes related to neurogenesis. Immunohistochemical analysis confirmed the temporal expression of neurogenic genes and showed an increased presence of NG2 cells positive for Purkinje cell protein-4 at the periphery of the ischemic lesion 12 days after FCI, as well as NeuN-positive NG2 cells 28 and 60 days after injury. These results suggest the potential development of neuron-like cells arising from NG2 glia in the ischemic tissue. Our study provides insights into the plasticity of NG2 glia and their capacity for neurogenesis after stroke.
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Affiliation(s)
- Lucie Janeckova
- Laboratory of Cell and Developmental Biology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Tomas Knotek
- Department of Cellular Neurophysiology, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czech Republic
- Second Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Jan Kriska
- Department of Cellular Neurophysiology, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czech Republic
| | - Zuzana Hermanova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czech Republic
- Second Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Denisa Kirdajova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jan Kubovciak
- Laboratory of Genomics and Bioinformatics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Linda Berkova
- Laboratory of Cell and Developmental Biology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jana Tureckova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czech Republic
| | - Sara Camacho Garcia
- Department of Cellular Neurophysiology, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czech Republic
| | - Katerina Galuskova
- Laboratory of Cell and Developmental Biology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Michal Kolar
- Laboratory of Genomics and Bioinformatics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Miroslava Anderova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czech Republic
| | - Vladimir Korinek
- Laboratory of Cell and Developmental Biology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
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8
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Altas B, Rhee HJ, Ju A, Solís HC, Karaca S, Winchenbach J, Kaplan-Arabaci O, Schwark M, Ambrozkiewicz MC, Lee C, Spieth L, Wieser GL, Chaugule VK, Majoul I, Hassan MA, Goel R, Wojcik SM, Koganezawa N, Hanamura K, Rotin D, Pichler A, Mitkovski M, de Hoz L, Poulopoulos A, Urlaub H, Jahn O, Saher G, Brose N, Rhee J, Kawabe H. Nedd4-2-dependent regulation of astrocytic Kir4.1 and Connexin43 controls neuronal network activity. J Cell Biol 2024; 223:e201902050. [PMID: 38032389 PMCID: PMC10689203 DOI: 10.1083/jcb.201902050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 10/21/2021] [Accepted: 11/02/2023] [Indexed: 12/01/2023] Open
Abstract
Nedd4-2 is an E3 ubiquitin ligase in which missense mutation is related to familial epilepsy, indicating its critical role in regulating neuronal network activity. However, Nedd4-2 substrates involved in neuronal network function have yet to be identified. Using mouse lines lacking Nedd4-1 and Nedd4-2, we identified astrocytic channel proteins inwardly rectifying K+ channel 4.1 (Kir4.1) and Connexin43 as Nedd4-2 substrates. We found that the expression of Kir4.1 and Connexin43 is increased upon conditional deletion of Nedd4-2 in astrocytes, leading to an elevation of astrocytic membrane ion permeability and gap junction activity, with a consequent reduction of γ-oscillatory neuronal network activity. Interestingly, our biochemical data demonstrate that missense mutations found in familial epileptic patients produce gain-of-function of the Nedd4-2 gene product. Our data reveal a process of coordinated astrocytic ion channel proteostasis that controls astrocyte function and astrocyte-dependent neuronal network activity and elucidate a potential mechanism by which aberrant Nedd4-2 function leads to epilepsy.
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Affiliation(s)
- Bekir Altas
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- International Max Planck Research School and the Göttingen Graduate School for Neurosciences, Biophysics and Molecular Biosciences, Göttingen, Germany
- The Göttingen Graduate School for Neurosciences, Biophysics, and Molecular Biosciences, PhD Program Systems Neuroscience, University of Göttingen, Göttingen, Germany
- Department of Pharmacology and Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Hong-Jun Rhee
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Anes Ju
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- The Göttingen Graduate School for Neurosciences, Biophysics, and Molecular Biosciences, PhD Program Systems Neuroscience, University of Göttingen, Göttingen, Germany
| | - Hugo Cruces Solís
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- International Max Planck Research School and the Göttingen Graduate School for Neurosciences, Biophysics and Molecular Biosciences, Göttingen, Germany
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Samir Karaca
- International Max Planck Research School and the Göttingen Graduate School for Neurosciences, Biophysics and Molecular Biosciences, Göttingen, Germany
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Jan Winchenbach
- The Göttingen Graduate School for Neurosciences, Biophysics, and Molecular Biosciences, PhD Program Systems Neuroscience, University of Göttingen, Göttingen, Germany
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Oykum Kaplan-Arabaci
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- The Göttingen Graduate School for Neurosciences, Biophysics, and Molecular Biosciences, PhD Program Molecular Physiology of the Brain, University of Göttingen, Göttingen, Germany
| | - Manuela Schwark
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Mateusz C. Ambrozkiewicz
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- International Max Planck Research School and the Göttingen Graduate School for Neurosciences, Biophysics and Molecular Biosciences, Göttingen, Germany
- Institute of Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - ChungKu Lee
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Lena Spieth
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Georg L. Wieser
- City Campus Light Microscopy Facility, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Viduth K. Chaugule
- Department of Epigenetics, Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Irina Majoul
- Institute of Biology, Center for Structural and Cell Biology in Medicine, University of Lübeck, Lübeck, Germany
| | - Mohamed A. Hassan
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Protein Research Department, Genetic Engineering and Biotechnology Research Institute (GEBRI), City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab City, Egypt
| | - Rashi Goel
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Sonja M. Wojcik
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Noriko Koganezawa
- Department of Pharmacology, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Kenji Hanamura
- Department of Pharmacology, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Daniela Rotin
- The Hospital for Sick Children and University of Toronto, Toronto, Canada
| | - Andrea Pichler
- Department of Epigenetics, Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Miso Mitkovski
- City Campus Light Microscopy Facility, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Livia de Hoz
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Alexandros Poulopoulos
- Department of Pharmacology and Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Bioanalytics, Institute for Clinical Chemistry, University Medical Center Göttingen, Göttingen, Germany
- Cluster of Excellence “Multiscale Bioimaging: From Molecular Machines to Networks of Excitable Cells” (MBExC), University of Göttingen, Göttingen, Germany
| | - Olaf Jahn
- Department of Molecular Neurobiology, Neuroproteomics Group, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Department of Psychiatry and Psychotherapy, Translational Neuroproteomics Group, University Medical Center Göttingen, Göttingen, Germany
| | - Gesine Saher
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Nils Brose
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - JeongSeop Rhee
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Hiroshi Kawabe
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Department of Pharmacology, Gunma University Graduate School of Medicine, Maebashi, Japan
- Division of Pathogenetic Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, Japan
- Department of Gerontology, Laboratory of Molecular Life Science, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation at Kobe, Kobe, Japan
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9
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Oertel FC, Hastermann M, Paul F. Delimiting MOGAD as a disease entity using translational imaging. Front Neurol 2023; 14:1216477. [PMID: 38333186 PMCID: PMC10851159 DOI: 10.3389/fneur.2023.1216477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 08/23/2023] [Indexed: 02/10/2024] Open
Abstract
The first formal consensus diagnostic criteria for myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) were recently proposed. Yet, the distinction of MOGAD-defining characteristics from characteristics of its important differential diagnoses such as multiple sclerosis (MS) and aquaporin-4 antibody seropositive neuromyelitis optica spectrum disorder (NMOSD) is still obstructed. In preclinical research, MOG antibody-based animal models were used for decades to derive knowledge about MS. In clinical research, people with MOGAD have been combined into cohorts with other diagnoses. Thus, it remains unclear to which extent the generated knowledge is specifically applicable to MOGAD. Translational research can contribute to identifying MOGAD characteristic features by establishing imaging methods and outcome parameters on proven pathophysiological grounds. This article reviews suitable animal models for translational MOGAD research and the current state and prospect of translational imaging in MOGAD.
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Affiliation(s)
- Frederike Cosima Oertel
- Experimental and Clinical Research Center, Max-Delbrück-Centrum für Molekulare Medizin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
- Neuroscience Clinical Research Center, Freie Universität Berlin and Humboldt-Universität zu Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
- Department of Neurology, Freie Universität Berlin and Humboldt-Universität zu Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Maria Hastermann
- Experimental and Clinical Research Center, Max-Delbrück-Centrum für Molekulare Medizin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
- Neuroscience Clinical Research Center, Freie Universität Berlin and Humboldt-Universität zu Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Friedemann Paul
- Experimental and Clinical Research Center, Max-Delbrück-Centrum für Molekulare Medizin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
- Neuroscience Clinical Research Center, Freie Universität Berlin and Humboldt-Universität zu Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
- Department of Neurology, Freie Universität Berlin and Humboldt-Universität zu Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
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10
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Anders JJ, Elwood BW, Kardon RH, Gramlich OW. Acriflavine, a HIF-1 inhibitor, preserves vision in an experimental autoimmune encephalomyelitis model of optic neuritis. Front Immunol 2023; 14:1271118. [PMID: 37942317 PMCID: PMC10628762 DOI: 10.3389/fimmu.2023.1271118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 09/25/2023] [Indexed: 11/10/2023] Open
Abstract
Introduction Optic neuritis (ON) is often an early sign of multiple sclerosis (MS), and recent studies show a link between HIF-1 pathway activation and inflammation. This study aimed to determine if inhibition of the HIF-1 pathway using the HIF-1a antagonist acriflavine (ACF) can reduce clinical progression and rescue the ocular phenotype in an experimental autoimmune encephalomyelitis (EAE) ON model. Methods EAE-related ON was induced in 60 female C57BL/6J mice by immunization with MOG33-55, and 20 EAE mice received daily systemic injections of ACF at 5 mg/kg. Changes in the visual function and structure of ACF-treated EAE mice were compared to those of placebo-injected EAE mice and naïve control mice. Results ACF treatment improved motor-sensory impairment along with preserving visual acuity and optic nerve function. Analysis of retinal ganglion cell complex alsoshowed preserved thickness correlating with increased survival of retinal ganglion cells and their axons. Optic nerve cell infiltration and magnitude of demyelination were decreased in ACF-treated EAE mice. Subsequent in vitro studies revealed improvements not only attributed to the inhibition of HIF-1 butalso to previously unappreciated interaction with the eIF2a/ATF4 axis in the unfolded protein response pathway. Discussion This study suggests that ACF treatment is effective in an animal model of MS via its pleiotropic effects on the inhibition of HIF-1 and UPR signaling, and it may be a viable approach to promote rehabilitation in MS.
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Affiliation(s)
- Jeffrey J. Anders
- Department of Ophthalmology and Visual Science, The University of Iowa, Iowa City, IA, United States
- Center for the Prevention and Treatment of Visual Loss, Iowa City Veterans Affairs (VA) Health Care System, Iowa City, IA, United States
| | - Benjamin W. Elwood
- Department of Ophthalmology and Visual Science, The University of Iowa, Iowa City, IA, United States
- Center for the Prevention and Treatment of Visual Loss, Iowa City Veterans Affairs (VA) Health Care System, Iowa City, IA, United States
| | - Randy H. Kardon
- Department of Ophthalmology and Visual Science, The University of Iowa, Iowa City, IA, United States
- Center for the Prevention and Treatment of Visual Loss, Iowa City Veterans Affairs (VA) Health Care System, Iowa City, IA, United States
| | - Oliver W. Gramlich
- Department of Ophthalmology and Visual Science, The University of Iowa, Iowa City, IA, United States
- Center for the Prevention and Treatment of Visual Loss, Iowa City Veterans Affairs (VA) Health Care System, Iowa City, IA, United States
- Department of Neuroscience and Pharmacology, The University of Iowa, Iowa City, IA, United States
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11
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Liu JY, Zhou L, Shen Y. Inward rectifying K ir4.1 channels regulate oligodendrocyte precursor cell differentiation and CNS myelination in vivo. Neurosci Lett 2023; 807:137278. [PMID: 37116573 DOI: 10.1016/j.neulet.2023.137278] [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: 03/05/2023] [Revised: 04/21/2023] [Accepted: 04/24/2023] [Indexed: 04/30/2023]
Abstract
The functions of Kir4.1 in oligodendrocyte development have been in controversial. We recently reported that inhibiting Kir4.1 impeded oligodendrocyte precursor cell (OPC) differentiation and oligodendrocyte (OL) maturation, due to Kir4.1 altering intracellular pH of OPCs through Na+/H+ exchangers. However, our conclusion was limited by in vitro observation, thereby it becomes necessary to seek in vivo evidence to determine the roles of Kir4.1 on OPC development and CNS myelination. Here, we used Olig1-Cre to knockout Kir4.1 in OPCs from the early developmental stage. We found that the cell-specific deletion of Kir4.1 significantly impeded OPC differentiation and reduced the number of mature OLs in the cerebral cortex and the corpus callosum. Hence, our in vivo evidence supports that Kir4.1 can regulate OPC differentiation and is essential to CNS myelination.
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Affiliation(s)
- Jia-Yu Liu
- Department of Physiology and Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Liang Zhou
- Key Laboratory of Brain Science, Guizhou Institution of Higher Education, Zunyi Medical University, Zunyi, People's Republic of China
| | - Ying Shen
- Department of Physiology and Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.
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12
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Kapell H, Fazio L, Dyckow J, Schwarz S, Cruz-Herranz A, Mayer C, Campos J, D’Este E, Möbius W, Cordano C, Pröbstel AK, Gharagozloo M, Zulji A, Narayanan Naik V, Delank A, Cerina M, Müntefering T, Lerma-Martin C, Sonner JK, Sin JH, Disse P, Rychlik N, Sabeur K, Chavali M, Srivastava R, Heidenreich M, Fitzgerald KC, Seebohm G, Stadelmann C, Hemmer B, Platten M, Jentsch TJ, Engelhardt M, Budde T, Nave KA, Calabresi PA, Friese MA, Green AJ, Acuna C, Rowitch DH, Meuth SG, Schirmer L. Neuron-oligodendrocyte potassium shuttling at nodes of Ranvier protects against inflammatory demyelination. J Clin Invest 2023; 133:e164223. [PMID: 36719741 PMCID: PMC10065072 DOI: 10.1172/jci164223] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 01/27/2023] [Indexed: 02/01/2023] Open
Abstract
Multiple sclerosis (MS) is a progressive inflammatory demyelinating disease of the CNS. Increasing evidence suggests that vulnerable neurons in MS exhibit fatal metabolic exhaustion over time, a phenomenon hypothesized to be caused by chronic hyperexcitability. Axonal Kv7 (outward-rectifying) and oligodendroglial Kir4.1 (inward-rectifying) potassium channels have important roles in regulating neuronal excitability at and around the nodes of Ranvier. Here, we studied the spatial and functional relationship between neuronal Kv7 and oligodendroglial Kir4.1 channels and assessed the transcriptional and functional signatures of cortical and retinal projection neurons under physiological and inflammatory demyelinating conditions. We found that both channels became dysregulated in MS and experimental autoimmune encephalomyelitis (EAE), with Kir4.1 channels being chronically downregulated and Kv7 channel subunits being transiently upregulated during inflammatory demyelination. Further, we observed that pharmacological Kv7 channel opening with retigabine reduced neuronal hyperexcitability in human and EAE neurons, improved clinical EAE signs, and rescued neuronal pathology in oligodendrocyte-Kir4.1-deficient (OL-Kir4.1-deficient) mice. In summary, our findings indicate that neuron-OL compensatory interactions promoted resilience through Kv7 and Kir4.1 channels and identify pharmacological activation of nodal Kv7 channels as a neuroprotective strategy against inflammatory demyelination.
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Affiliation(s)
- Hannah Kapell
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Luca Fazio
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster (UKM), Münster, Germany
- Department of Neurology, University of Düsseldorf, Dusseldorf, Germany
| | - Julia Dyckow
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Sophia Schwarz
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Andrés Cruz-Herranz
- Weill Institute for Neurosciences, Department of Neurology, UCSF, San Francisco, California, USA
| | - Christina Mayer
- Institute of Neuroimmunology and Multiple Sclerosis, Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Joaquin Campos
- Chica and Heinz Schaller Research Group, Institute of Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
| | - Elisa D’Este
- Optical Microscopy Facility, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Wiebke Möbius
- Electron Microscopy Core Unit, Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
- Cluster of Excellence, “Multiscale Bioimaging: from Molecular Machines to Network of Excitable Cells” (MBExC), University of Göttingen, Göttingen, Germany
| | - Christian Cordano
- Weill Institute for Neurosciences, Department of Neurology, UCSF, San Francisco, California, USA
| | - Anne-Katrin Pröbstel
- Weill Institute for Neurosciences, Department of Neurology, UCSF, San Francisco, California, USA
- Neurologic Clinic and Policlinic and Research Center for Clinical Neuroimmunology and Neuroscience Basel, Departments of Medicine, Biomedicine, and Clinical Research, University Hospital of Basel, University of Basel, Basel, Switzerland
| | - Marjan Gharagozloo
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Amel Zulji
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Venu Narayanan Naik
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster (UKM), Münster, Germany
| | - Anna Delank
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster (UKM), Münster, Germany
| | - Manuela Cerina
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster (UKM), Münster, Germany
| | | | - Celia Lerma-Martin
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Jana K. Sonner
- Chica and Heinz Schaller Research Group, Institute of Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
| | - Jung Hyung Sin
- Weill Institute for Neurosciences, Department of Neurology, UCSF, San Francisco, California, USA
| | - Paul Disse
- Institute for Genetics of Heart Diseases (IfGH), Cellular Electrophysiology and Molecular Biology, UKM, Münster, Germany
- University of Münster, Chembion, Münster, Germany
| | - Nicole Rychlik
- University of Münster, Chembion, Münster, Germany
- Institute of Physiology I, University of Münster, Münster, Germany
| | - Khalida Sabeur
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research and
- Department of Pediatrics, UCSF, San Francisco, California, USA
| | - Manideep Chavali
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research and
- Department of Pediatrics, UCSF, San Francisco, California, USA
| | - Rajneesh Srivastava
- Department of Neurology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Matthias Heidenreich
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP) and Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Kathryn C. Fitzgerald
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Guiscard Seebohm
- Institute for Genetics of Heart Diseases (IfGH), Cellular Electrophysiology and Molecular Biology, UKM, Münster, Germany
| | - Christine Stadelmann
- Electron Microscopy Core Unit, Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
- Institute of Neuropathology, University Medical Center, Göttingen, Germany
| | - Bernhard Hemmer
- Department of Neurology, School of Medicine, Technical University of Munich, Munich, Germany
- Munich Cluster for Systems Neurology, Munich, Germany
| | - Michael Platten
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
- DKTK Clinical Cooperation Unit Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), INF 280, Heidelberg, Germany
- Interdisciplinary Center for Neurosciences (IZN) and
- Mannheim Center for Translational Neuroscience and Institute for Innate Immunoscience, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Thomas J. Jentsch
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP) and Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
- Neurocure Cluster of Excellence, Charité University Medicine Berlin, Berlin, Germany
| | - Maren Engelhardt
- Mannheim Center for Translational Neuroscience and Institute for Innate Immunoscience, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
- Institute of Neuroanatomy, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
- Institute of Anatomy and Cell Biology, Johannes Kepler University Linz, Linz, Austria
| | - Thomas Budde
- Institute of Physiology I, University of Münster, Münster, Germany
| | - Klaus-Armin Nave
- Electron Microscopy Core Unit, Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Peter A. Calabresi
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Manuel A. Friese
- Institute of Neuroimmunology and Multiple Sclerosis, Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Ari J. Green
- Weill Institute for Neurosciences, Department of Neurology, UCSF, San Francisco, California, USA
- Department of Ophthalmology, UCSF, San Francisco, California, USA
| | - Claudio Acuna
- Chica and Heinz Schaller Research Group, Institute of Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
| | - David H. Rowitch
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research and
- Department of Pediatrics, UCSF, San Francisco, California, USA
- Wellcome Trust–Medical Research Council Stem Cell Institute and
- Department of Paediatrics, University of Cambridge, Cambridge, United Kingdom
- Department of Neurosurgery, UCSF, San Francisco, California, USA
| | - Sven G. Meuth
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster (UKM), Münster, Germany
- Department of Neurology, University of Düsseldorf, Dusseldorf, Germany
| | - Lucas Schirmer
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
- Interdisciplinary Center for Neurosciences (IZN) and
- Mannheim Center for Translational Neuroscience and Institute for Innate Immunoscience, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
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13
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Procacci NM, Hastings RL, Aziz AA, Christiansen NM, Zhao J, DeAngeli C, LeBlanc N, Notterpek L, Valdez G, Gould TW. Kir4.1 is specifically expressed and active in non-myelinating Schwann cells. Glia 2023; 71:926-944. [PMID: 36479906 PMCID: PMC9931657 DOI: 10.1002/glia.24315] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 11/18/2022] [Accepted: 11/22/2022] [Indexed: 12/13/2022]
Abstract
Non-myelinating Schwann cells (NMSC) play important roles in peripheral nervous system formation and function. However, the molecular identity of these cells remains poorly defined. We provide evidence that Kir4.1, an inward-rectifying K+ channel encoded by the KCNJ10 gene, is specifically expressed and active in NMSC. Immunostaining revealed that Kir4.1 is present in terminal/perisynaptic SCs (TPSC), synaptic glia at neuromuscular junctions (NMJ), but not in myelinating SCs (MSC) of adult mice. To further examine the expression pattern of Kir4.1, we generated BAC transgenic Kir4.1-CreERT2 mice and crossed them to the tdTomato reporter line. Activation of CreERT2 with tamoxifen after the completion of myelination onset led to robust expression of tdTomato in NMSC, including Remak Schwann cells (RSC) along peripheral nerves and TPSC, but not in MSC. In contrast, activating CreERT2 before and during the onset of myelination led to tdTomato expression in NMSC and MSC. These observations suggest that immature SC express Kir4.1, and its expression is then downregulated selectively in myelin-forming SC. In support, we found that while activating CreERT2 induces tdTomato expression in immature SC, it fails to induce tdTomato in MSC associated with sensory axons in culture. NMSC derived from neonatal sciatic nerve were shown to express Kir4.1 and exhibit barium-sensitive inwardly rectifying macroscopic K+ currents. Thus, this study identified Kir4.1 as a potential modulator of immature SC and NMSC function. Additionally, it established a novel transgenic mouse line to introduce or delete genes in NMSC.
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Affiliation(s)
- Nicole M Procacci
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Robert Louis Hastings
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island, USA
| | - Aamir A Aziz
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Nina M Christiansen
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Jie Zhao
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Claire DeAngeli
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Normand LeBlanc
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Lucia Notterpek
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Gregorio Valdez
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island, USA
| | - Thomas W Gould
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
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14
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Wang Y, Sun J, Zhu K, Wang D, Zhao X, Zhang H, Wu S, Wang Y, Wang J. Microglial aryl hydrocarbon receptor enhances phagocytic function via SYK and promotes remyelination in the cuprizone mouse model of demyelination. J Neuroinflammation 2023; 20:83. [PMID: 36966295 PMCID: PMC10040134 DOI: 10.1186/s12974-023-02764-3] [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: 09/12/2022] [Accepted: 03/11/2023] [Indexed: 03/27/2023] Open
Abstract
Multiple sclerosis (MS) is an inflammatory-mediated demyelinating disease of the central nervous system (CNS). Although studies have demonstrated that microglia facilitate remyelination in demyelinating diseases, the underlying mechanisms are still not fully characterized. We found that aryl hydrocarbon receptor (AhR), an environment sensor, was upregulated within the corpus callosum in the cuprizone model of CNS demyelination, and upregulated AhR was mainly confined to microglia. Deletion of AhR in adult microglia inhibited efficient remyelination. Transcriptome analysis using RNA-seq revealed that AhR-deficient microglia displayed impaired gene expression signatures associated with lysosome and phagocytotic pathways. Furthermore, AhR-deficient microglia showed impaired clearance of myelin debris and defected phagocytic capacity. Further investigation of target genes of AhR revealed that spleen tyrosine kinase (SYK) is the downstream effector of AhR and mediated the phagocytic capacity of microglia. Additionally, AhR deficiency in microglia aggravated CNS inflammation during demyelination. Altogether, our study highlights an essential role for AhR in microglial phagocytic function and suggests the therapeutic potential of AhR in demyelinating diseases.
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Affiliation(s)
- Yumeng Wang
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Science, Institutes of Integrative Medicine, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jingxian Sun
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Science, Institutes of Integrative Medicine, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Shanghai Medical College, Fudan University, Shanghai, China
| | - Keying Zhu
- Department of Clinical Neuroscience, Karolinska Institute, Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Danjie Wang
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Science, Institutes of Integrative Medicine, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xiaoqiang Zhao
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Science, Institutes of Integrative Medicine, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Shanghai Medical College, Fudan University, Shanghai, China
| | - Hongyu Zhang
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Science, Institutes of Integrative Medicine, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Shanghai Medical College, Fudan University, Shanghai, China
| | - Shuai Wu
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yanqing Wang
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Science, Institutes of Integrative Medicine, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Shanghai Medical College, Fudan University, Shanghai, China.
| | - Jun Wang
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Science, Institutes of Integrative Medicine, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Shanghai Medical College, Fudan University, Shanghai, China.
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15
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Pan L, Trimarco A, Zhang AJ, Fujimori K, Urade Y, Sun LO, Taveggia C, Zhang Y. Oligodendrocyte-lineage cell exocytosis and L-type prostaglandin D synthase promote oligodendrocyte development and myelination. eLife 2023; 12:e77441. [PMID: 36779701 PMCID: PMC9946447 DOI: 10.7554/elife.77441] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 02/12/2023] [Indexed: 02/14/2023] Open
Abstract
In the developing central nervous system, oligodendrocyte precursor cells (OPCs) differentiate into oligodendrocytes, which form myelin around axons. Oligodendrocytes and myelin are essential for the function of the central nervous system, as evidenced by the severe neurological symptoms that arise in demyelinating diseases such as multiple sclerosis and leukodystrophy. Although many cell-intrinsic mechanisms that regulate oligodendrocyte development and myelination have been reported, it remains unclear whether interactions among oligodendrocyte-lineage cells (OPCs and oligodendrocytes) affect oligodendrocyte development and myelination. Here, we show that blocking vesicle-associated membrane protein (VAMP) 1/2/3-dependent exocytosis from oligodendrocyte-lineage cells impairs oligodendrocyte development, myelination, and motor behavior in mice. Adding oligodendrocyte-lineage cell-secreted molecules to secretion-deficient OPC cultures partially restores the morphological maturation of oligodendrocytes. Moreover, we identified L-type prostaglandin D synthase as an oligodendrocyte-lineage cell-secreted protein that promotes oligodendrocyte development and myelination in vivo. These findings reveal a novel autocrine/paracrine loop model for the regulation of oligodendrocyte and myelin development.
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Affiliation(s)
- Lin Pan
- Department of Psychiatry and Biobehavioral Sciences, Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los AngelesLos AngelesUnited States
| | - Amelia Trimarco
- Division of Neuroscience, IRCCS, San Raffaele HospitalMilanItaly
| | - Alice J Zhang
- Department of Psychiatry and Biobehavioral Sciences, Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los AngelesLos AngelesUnited States
| | - Ko Fujimori
- Department of Pathobiochemistry, Osaka Medical and Pharmaceutical UniversityOsakaJapan
| | - Yoshihiro Urade
- Hirono Satellite, Isotope Science Center, The University of TokyoFukushimaJapan
| | - Lu O Sun
- Department of Molecular Biology, University of Texas Southwestern Medical CenterDallasUnited States
| | - Carla Taveggia
- Division of Neuroscience, IRCCS, San Raffaele HospitalMilanItaly
| | - Ye Zhang
- Department of Psychiatry and Biobehavioral Sciences, Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los AngelesLos AngelesUnited States
- Brain Research Institute, University of California, Los AngelesLos AngelesUnited States
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los AngelesLos AngelesUnited States
- Molecular Biology Institute, University of California, Los AngelesLos AngelesUnited States
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16
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Kurki SN, Uvarov P, Pospelov AS, Trontti K, Hübner AK, Srinivasan R, Watanabe M, Hovatta I, Hübner CA, Kaila K, Virtanen MA. Expression patterns of NKCC1 in neurons and non-neuronal cells during cortico-hippocampal development. Cereb Cortex 2022; 33:5906-5923. [PMID: 36573432 PMCID: PMC10183754 DOI: 10.1093/cercor/bhac470] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 11/05/2022] [Accepted: 11/06/2022] [Indexed: 12/28/2022] Open
Abstract
Abstract
The Na-K-2Cl cotransporter NKCC1 is widely expressed in cells within and outside the brain. However, our understanding of its roles in brain functions throughout development, as well as in neuropsychiatric and neurological disorders, has been severely hindered by the lack of reliable data on its developmental and (sub)cellular expression patterns. We provide here the first properly controlled analysis of NKCC1 protein expression in various cell types of the mouse brain using custom-made antibodies and an NKCC1 knock-out validated immunohistochemical procedure, with parallel data based on advanced mRNA approaches. NKCC1 protein and mRNA are expressed at remarkably high levels in oligodendrocytes. In immature neurons, NKCC1 protein was located in the somata, whereas in adult neurons, only NKCC1 mRNA could be clearly detected. NKCC1 immunoreactivity is also seen in microglia, astrocytes, developing pericytes, and in progenitor cells of the dentate gyrus. Finally, a differential expression of NKCC1 splice variants was observed, with NKCC1a predominating in non-neuronal cells and NKCC1b in neurons. Taken together, our data provide a cellular basis for understanding NKCC1 functions in the brain and enable the identification of major limitations and promises in the development of neuron-targeting NKCC1-blockers.
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Affiliation(s)
- Samu N Kurki
- University of Helsinki Molecular and Integrative Biosciences, , 00014 Helsinki , Finland
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
| | - Pavel Uvarov
- University of Helsinki Molecular and Integrative Biosciences, , 00014 Helsinki , Finland
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
| | - Alexey S Pospelov
- University of Helsinki Molecular and Integrative Biosciences, , 00014 Helsinki , Finland
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
| | - Kalevi Trontti
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
- University of Helsinki SleepWell Research Program, Faculty of Medicine, , 00014 Helsinki , Finland
- University of Helsinki Department of Psychology and Logopedics, , 00014 Helsinki , Finland
| | - Antje K Hübner
- Jena University Hospital, Friedrich Schiller Universität Institute of Human Genetics, , 07747 Jena , Germany
| | - Rakenduvadhana Srinivasan
- University of Helsinki Molecular and Integrative Biosciences, , 00014 Helsinki , Finland
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
| | - Masahiko Watanabe
- Hokkaido University Department of Anatomy, Faculty of Medicine, , Sapporo 060–8638 , Japan
| | - Iiris Hovatta
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
- University of Helsinki SleepWell Research Program, Faculty of Medicine, , 00014 Helsinki , Finland
- University of Helsinki Department of Psychology and Logopedics, , 00014 Helsinki , Finland
| | - Christian A Hübner
- Jena University Hospital, Friedrich Schiller Universität Institute of Human Genetics, , 07747 Jena , Germany
| | - Kai Kaila
- University of Helsinki Molecular and Integrative Biosciences, , 00014 Helsinki , Finland
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
| | - Mari A Virtanen
- University of Helsinki Molecular and Integrative Biosciences, , 00014 Helsinki , Finland
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
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17
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Hong X, Jian Y, Ding S, Zhou J, Zheng X, Zhang H, Zhou B, Zhuang C, Wan J, Tong X. Kir4.1 channel activation in NG2 glia contributes to remyelination in ischemic stroke. EBioMedicine 2022; 87:104406. [PMID: 36527899 PMCID: PMC9791134 DOI: 10.1016/j.ebiom.2022.104406] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 11/23/2022] [Accepted: 11/23/2022] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Stroke is one of the most common neurological diseases in the world and is clinically manifested by transient or permanent brain dysfunction. It has a high mortality and disability rate, which severely affects people's health and diminishes the quality of life. However, there is no efficient treatment that can be considered curative and there are other less well-known theories of pathogenesis. Therefore, it is imperative to gain a full understanding of the pathophysiology of ischemia and to seek new therapeutic strategies. METHODS We first examined Kir4.1 channel and myelin based protein (MBP) expression in brain tissues from acute ischemic patients by Western blotting. We then established a transient ischemic mouse model (tMCAO) to conduct molecular, cell biological, transmission electron microscopy and pharmacokinetic studies, as well as in Kir4.1 cKO mice. Finally, neuroimaging and behavioral analyses were used to examine whether activation of Kir4.1 channel by luteolin could contribute to neuronal functional recovery in ischemic stroke. FINDINGS In acute ischemic stroke patients, we first demonstrated that Kir4.1 ion channels were greatly impaired and a severe demyelination of axons occurred in ischemic infarction area of cerebral cortex in these patients. Further evidence showed that the deficits of Kir4.1 channels in NG2 glia led to the myelin loss of axons in a transient ischemic mouse model (tMCAO). Treating ischemic mice with a natural botanical extract, luteolin augmented Kir4.1 channel currents in NG2 glia and consequently promoted remyelination of axons, alleviated the infarction area and ultimately improved motor function in a series of behavioral tests. INTERPRETATION Targeting Kir4.1 ion channels expressed in NG2 glial cells by luteolin treatment highlights an effective therapeutic strategy for a prompt brain functional recovery in ischemic stroke. FUNDING This work was supported by grants from the Ministry of Science and Technology China Brain Initiative (2022ZD0204702, to X.T.), the National Natural Science Foundation of China (82271466, 82171279, 31970904 and 31571063), the Program for Professor of Special Appointment (Eastern Scholar for Dr. X.T.) at Shanghai Institutions for Higher Learning (1510000084), Shanghai Pujiang Talent Award (15PJ1404600), Shanghai Municipal Science and Technology Major Project (2018SHZDZX05) and Shanghai Science and Technology Project (17411954000).
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Affiliation(s)
- Xiaoqi Hong
- Songjiang Institute and Songjiang Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China,Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yujin Jian
- Songjiang Institute and Songjiang Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China,Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shenghao Ding
- Department of Neurosurgery, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jianpo Zhou
- Department of Neurosurgery, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiaoli Zheng
- Songjiang Institute and Songjiang Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China,Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Huimin Zhang
- Songjiang Institute and Songjiang Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China,Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Butian Zhou
- Songjiang Institute and Songjiang Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China,Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Canbin Zhuang
- Department of Neurosurgery, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jieqing Wan
- Department of Neurosurgery, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China,Corresponding author.
| | - Xiaoping Tong
- Songjiang Institute and Songjiang Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China,Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China,Shanghai Research Center for Brain Science and Brain-Inspired Intelligence, Shanghai, China,Corresponding author.
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18
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Ehtesham N, Mosallaei M, Beheshtian M, Khoshbakht S, Fadaee M, Vazehan R, Faraji Zonooz M, Karimzadeh P, Kahrizi K, Najmabadi H. Characterizing Genotypes and Phenotypes Associated with Dysfunction of Channel-Encoding Genes in a Cohort of Patients with Intellectual Disability. ARCHIVES OF IRANIAN MEDICINE 2022; 25:788-797. [PMID: 37543906 PMCID: PMC10685845 DOI: 10.34172/aim.2022.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 12/20/2021] [Indexed: 08/08/2023]
Abstract
BACKGROUND Ion channel dysfunction in the brain can lead to impairment of neuronal membranes and generate several neurological diseases, especially neurodevelopmental disorders. METHODS In this study, we set out to delineate the genotype and phenotype spectrums of 14 Iranian patients from 7 families with intellectual disability (ID) and/or developmental delay (DD) in whom genetic mutations were identified by next-generation sequencing (NGS) in 7 channel-encoding genes: KCNJ10, KCNQ3, KCNK6, CACNA1C, CACNA1G, SCN8A, and GRIN2B. Moreover, the data of 340 previously fully reported ID and/or DD cases with a mutation in any of these seven genes were combined with our patients to clarify the genotype and phenotype spectrum in this group. RESULTS In total, the most common phenotypes in 354 cases with ID/DD in whom mutation in any of these 7 channel-encoding genes was identified were as follows: ID (77.4%), seizure (69.8%), DD (59.8%), behavioral abnormality (29.9%), hypotonia (21.7%), speech disorder (21.5%), gait disturbance (20.9%), and ataxia (20.3%). Electroencephalography abnormality (33.9%) was the major brain imaging abnormality. CONCLUSION The results of this study broaden the molecular spectrum of channel pathogenic variants associated with different clinical presentations in individuals with ID and/or DD.
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Affiliation(s)
- Naeim Ehtesham
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Meysam Mosallaei
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Maryam Beheshtian
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Shahrouz Khoshbakht
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Mahsa Fadaee
- Kariminejad – Najmabadi Pathology & Genetics Center, Tehran, Iran
| | - Raheleh Vazehan
- Kariminejad – Najmabadi Pathology & Genetics Center, Tehran, Iran
| | | | - Parvaneh Karimzadeh
- Department of Pediatric Neurology, School of Medicine, Pediatric Neurology Research Center, Mofid Children’s Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Kimia Kahrizi
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Hossein Najmabadi
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
- Kariminejad – Najmabadi Pathology & Genetics Center, Tehran, Iran
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19
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Staruschenko A, Hodges MR, Palygin O. Kir5.1 channels: potential role in epilepsy and seizure disorders. Am J Physiol Cell Physiol 2022; 323:C706-C717. [PMID: 35848616 PMCID: PMC9448276 DOI: 10.1152/ajpcell.00235.2022] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 07/06/2022] [Accepted: 07/08/2022] [Indexed: 11/22/2022]
Abstract
Inwardly rectifying potassium (Kir) channels are broadly expressed in many mammalian organ systems, where they contribute to critical physiological functions. However, the importance and function of the Kir5.1 channel (encoded by the KCNJ16 gene) have not been fully recognized. This review focuses on the recent advances in understanding the expression patterns and functional roles of Kir5.1 channels in fundamental physiological systems vital to potassium homeostasis and neurological disorders. Recent studies have described the role of Kir5.1-forming Kir channels in mouse and rat lines with mutations in the Kcnj16 gene. The animal research reveals distinct renal and neurological phenotypes, including pH and electrolyte imbalances, blunted ventilatory responses to hypercapnia/hypoxia, and seizure disorders. Furthermore, it was confirmed that these phenotypes are reminiscent of those in patient cohorts in which mutations in the KCNJ16 gene have also been identified, further suggesting a critical role for Kir5.1 channels in homeostatic/neural systems health and disease. Future studies that focus on the many functional roles of these channels, expanded genetic screening in human patients, and the development of selective small-molecule inhibitors for Kir5.1 channels, will continue to increase our understanding of this unique Kir channel family member.
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Affiliation(s)
- Alexander Staruschenko
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, Florida
- Hypertension and Kidney Research Center, University of South Florida, Tampa, Florida
- James A. Haley Veterans Hospital, Tampa, Florida
| | - Matthew R Hodges
- Department of Physiology and Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Oleg Palygin
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina
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20
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Collongues N, Becker G, Jolivel V, Ayme-Dietrich E, de Seze J, Binamé F, Patte-Mensah C, Monassier L, Mensah-Nyagan AG. A Narrative Review on Axonal Neuroprotection in Multiple Sclerosis. Neurol Ther 2022; 11:981-1042. [PMID: 35610531 PMCID: PMC9338208 DOI: 10.1007/s40120-022-00363-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 05/03/2022] [Indexed: 01/08/2023] Open
Abstract
Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) resulting in demyelination and neurodegeneration. The therapeutic strategy is now largely based on reducing inflammation with immunosuppressive drugs. Unfortunately, when disease progression is observed, no drug offers neuroprotection apart from its anti-inflammatory effect. In this review, we explore current knowledge on the assessment of neurodegeneration in MS and look at putative targets that might prove useful in protecting the axon from degeneration. Among them, Bruton's tyrosine kinase inhibitors, anti-apoptotic and antioxidant agents, sex hormones, statins, channel blockers, growth factors, and molecules preventing glutamate excitotoxicity have already been studied. Some of them have reached phase III clinical trials and carry a great message of hope for our patients with MS.
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Affiliation(s)
- Nicolas Collongues
- Department of Neurology, University Hospital of Strasbourg, Strasbourg, France. .,Center for Clinical Investigation, INSERM U1434, Strasbourg, France. .,Biopathology of Myelin, Neuroprotection and Therapeutic Strategy, INSERM U1119, Strasbourg, France. .,University Department of Pharmacology, Addictology, Toxicology and Therapeutic, Strasbourg University, Strasbourg, France.
| | - Guillaume Becker
- University Department of Pharmacology, Addictology, Toxicology and Therapeutic, Strasbourg University, Strasbourg, France.,NeuroCardiovascular Pharmacology and Toxicology Laboratory, UR7296, University Hospital of Strasbourg, Strasbourg, France
| | - Valérie Jolivel
- Biopathology of Myelin, Neuroprotection and Therapeutic Strategy, INSERM U1119, Strasbourg, France
| | - Estelle Ayme-Dietrich
- University Department of Pharmacology, Addictology, Toxicology and Therapeutic, Strasbourg University, Strasbourg, France.,NeuroCardiovascular Pharmacology and Toxicology Laboratory, UR7296, University Hospital of Strasbourg, Strasbourg, France
| | - Jérôme de Seze
- Department of Neurology, University Hospital of Strasbourg, Strasbourg, France.,Center for Clinical Investigation, INSERM U1434, Strasbourg, France.,Biopathology of Myelin, Neuroprotection and Therapeutic Strategy, INSERM U1119, Strasbourg, France
| | - Fabien Binamé
- Biopathology of Myelin, Neuroprotection and Therapeutic Strategy, INSERM U1119, Strasbourg, France
| | - Christine Patte-Mensah
- Biopathology of Myelin, Neuroprotection and Therapeutic Strategy, INSERM U1119, Strasbourg, France
| | - Laurent Monassier
- University Department of Pharmacology, Addictology, Toxicology and Therapeutic, Strasbourg University, Strasbourg, France.,NeuroCardiovascular Pharmacology and Toxicology Laboratory, UR7296, University Hospital of Strasbourg, Strasbourg, France
| | - Ayikoé Guy Mensah-Nyagan
- Biopathology of Myelin, Neuroprotection and Therapeutic Strategy, INSERM U1119, Strasbourg, France
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21
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Failed remyelination of the nonhuman primate optic nerve leads to axon degeneration, retinal damages, and visual dysfunction. Proc Natl Acad Sci U S A 2022; 119:e2115973119. [PMID: 35235463 PMCID: PMC8916013 DOI: 10.1073/pnas.2115973119] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Promotion of remyelination has become a new therapeutic avenue to prevent neuronal degeneration and promote recovery in white matter diseases, such as multiple sclerosis (MS). To date most of these strategies have been developed in short-lived rodent models of demyelination, which spontaneously repair. Well-defined nonhuman primate models closer to man would allow us to efficiently advance therapeutic approaches. Here we present a nonhuman primate model of optic nerve demyelination that recapitulates several features of MS lesions. The model leads to failed remyelination, associated with progressive axonal degeneration and visual dysfunction, thus providing the missing link to translate emerging preclinical therapies to the clinic for myelin disorders such as MS. White matter disorders of the central nervous system (CNS), such as multiple sclerosis (MS), lead to failure of nerve conduction and long-lasting neurological disabilities affecting a variety of sensory and motor systems, including vision. While most disease-modifying therapies target the immune and inflammatory response, the promotion of remyelination has become a new therapeutic avenue to prevent neuronal degeneration and promote recovery. Most of these strategies have been developed in short-lived rodent models of demyelination, which spontaneously repair and do not reflect the size, organization, and biology of the human CNS. Thus, well-defined nonhuman primate models are required to efficiently advance therapeutic approaches for patients. Here, we followed the consequence of long-term toxin-induced demyelination of the macaque optic nerve on remyelination and axon preservation, as well as its impact on visual functions. Findings from oculomotor behavior, ophthalmic examination, electrophysiology, and retinal imaging indicate visual impairment involving the optic nerve and retina. These visual dysfunctions fully correlated at the anatomical level, with sustained optic nerve demyelination, axonal degeneration, and alterations of the inner retinal layers. This nonhuman primate model of chronic optic nerve demyelination associated with axonal degeneration and visual dysfunction, recapitulates several key features of MS lesions and should be instrumental in providing the missing link to translate emerging repair promyelinating/neuroprotective therapies to the clinic for myelin disorders, such as MS.
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22
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Chen JF, Wang F, Huang NX, Xiao L, Mei F. Oligodendrocytes and Myelin: Active players in Neurodegenerative brains? Dev Neurobiol 2022; 82:160-174. [PMID: 35081276 DOI: 10.1002/dneu.22867] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 01/18/2022] [Accepted: 01/19/2022] [Indexed: 11/10/2022]
Abstract
Oligodendrocytes (OLs) are a major type of glial cells in the central nervous system that generate multiple myelin sheaths to wrap axons. Myelin ensures fast and efficient propagation of action potentials along axons and supports neurons with nourishment. The decay of OLs and myelin has been implicated in age-related neurodegenerative diseases and these changes are generally considered as an inevitable result of neuron loss and axon degeneration. Noticeably, OLs and myelin undergo dynamic changes in healthy adult brains, that is, newly formed OLs are continuously added throughout life from the differentiation of oligodendrocyte precursor cells (OPCs) and the pre-existing myelin sheaths may undergo degeneration or remodeling. Increasing evidence has shown that changes in OLs and myelin are present in the early stages of neurodegenerative diseases, and even prior to significant neuronal loss and functional deficits. More importantly, oligodendroglia-specific manipulation, by either deletion of the disease gene or enhancement of myelin renewal, can alleviate functional impairments in neurodegenerative animal models. These findings underscore the possibility that OLs and myelin are not passively but actively involved in neurodegenerative diseases and may play an important role in modulating neuronal function and survival. In this review, we summarize recent work characterizing OL and myelin changes in both healthy and neurodegenerative brains and discuss the potential of targeting oligodendroglial cells in treating neurodegenerative diseases. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Jing-Fei Chen
- Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Department of Histology and Embryology, Third Military Medical University, Chongqing, 400038, China
| | - Fei Wang
- Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Department of Histology and Embryology, Third Military Medical University, Chongqing, 400038, China
| | - Nan-Xing Huang
- Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Department of Histology and Embryology, Third Military Medical University, Chongqing, 400038, China
| | - Lan Xiao
- Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Department of Histology and Embryology, Third Military Medical University, Chongqing, 400038, China
| | - Feng Mei
- Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Department of Histology and Embryology, Third Military Medical University, Chongqing, 400038, China
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23
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Li H, Chen Y, Niu J, Yi C. New insights into the immunologic role of oligodendrocyte lineage cells in demyelination diseases. J Biomed Res 2022; 36:343-352. [PMID: 35578762 PMCID: PMC9548433 DOI: 10.7555/jbr.36.20220016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Oligodendrocyte lineage cells (OL-lineage cells) are a cell population that are crucial for mammalian central nervous system (CNS) myelination. OL-lineage cells go through developmental stages, initially differentiating into oligodendrocyte precursor cells (OPCs), before becoming immature oligodendrocytes, then mature oligodendrocytes (OLs). While the main function of cell lineage is in myelin formation, and increasing number of studies have turned to explore the immunological characteristics of these cells. Initially, these studies focused on discovering how OPCs and OLs are affected by the immune system, and then, how these immunological changes influence the myelination process. However, recent studies have uncovered another feature of OL-lineage cells in our immune systems. It would appear that OL-lineage cells also express immunological factors such as cytokines and chemokines in response to immune activation, and the expression of these factors changes under various pathologic conditions. Evidence suggests that OL-lineage cells actually modulate immune functions. Indeed, OL-lineage cells appear to play both "victim" and "agent" in the CNS which raises a number of questions. Here, we summarize immunologic changes in OL-lineage cells and their effects, as well as consider OL-lineage cell changes which influence immune cells under pathological conditions. We also describe some of the underlying mechanisms of these changes and their effects. Finally, we describe several studies which use OL-lineage cells as immunotherapeutic targets for demyelination diseases.
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Affiliation(s)
- Hui Li
- Research Centre, the Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518107, China
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Chongqing 400038, China
| | - Yang Chen
- Research Centre, the Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518107, China
| | - Jianqin Niu
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Chongqing 400038, China
- Jianqin Niu, Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Gaotanyan Main street, Chongqing 400038, China. Tel: +86-13668016001, E-mail:
| | - Chenju Yi
- Research Centre, the Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518107, China
- Chenju Yi, Research Centre, the Seventh Affiliated Hospital of Sun Yat-sen University, 628 Zhenyuan Road, Guangming (New) District, Shenzhen 518107, China. Tel: +86-13419189905, E-mail:
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24
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Bonetto G, Belin D, Káradóttir RT. Myelin: A gatekeeper of activity-dependent circuit plasticity? Science 2021; 374:eaba6905. [PMID: 34618550 DOI: 10.1126/science.aba6905] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Giulia Bonetto
- Wellcome-Medical Research Council Cambridge Stem Cell Institute and Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - David Belin
- Department of Psychology, University of Cambridge, Cambridge, UK
| | - Ragnhildur Thóra Káradóttir
- Wellcome-Medical Research Council Cambridge Stem Cell Institute and Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.,Department of Physiology, Biomedical Centre, Faculty of Medicine, University of Iceland, Reykjavik, Iceland
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25
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Swire M, Assinck P, McNaughton PA, Lyons DA, Ffrench-Constant C, Livesey MR. Oligodendrocyte HCN2 Channels Regulate Myelin Sheath Length. J Neurosci 2021; 41:7954-7964. [PMID: 34341156 PMCID: PMC8460148 DOI: 10.1523/jneurosci.2463-20.2021] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 06/16/2021] [Accepted: 07/06/2021] [Indexed: 11/21/2022] Open
Abstract
Oligodendrocytes generate myelin sheaths vital for the formation, health, and function of the CNS. Myelin sheath length is a key property that determines axonal conduction velocity and is known to be variable across the CNS. Myelin sheath length can be modified by neuronal activity, suggesting that dynamic regulation of sheath length might contribute to the functional plasticity of neural circuits. Although the mechanisms that establish and refine myelin sheath length are important determinants of brain function, our understanding of these remains limited. In recent years, the membranes of myelin sheaths have been increasingly recognized to contain ion channels and transporters that are associated with specific important oligodendrocyte functions, including metabolic support of axons and the regulation of ion homeostasis, but none have been shown to influence sheath architecture. In this study, we determined that hyperpolarization-activated, cyclic nucleotide-gated (HCN) ion channels, typically associated with neuronal and cardiac excitability, regulate myelin sheath length. Using both in vivo and in vitro approaches, we show that oligodendrocytes abundantly express functional, predominantly HCN2 subunit-containing ion channels. These HCN ion channels retain key pharmacological and biophysical features and regulate the resting membrane potential of myelinating oligodendrocytes. Further, reduction of their function via pharmacological blockade or generation of transgenic mice with two independent oligodendrocyte-specific HCN2 knock-out strategies reduced myelin sheath length. We conclude that HCN2 ion channels are key determinants of myelin sheath length in the CNS.SIGNIFICANCE STATEMENT Myelin sheath length is a critical determinant of axonal conduction velocity, but the signaling mechanisms responsible for determining sheath length are poorly understood. Here we find that oligodendrocytes express functional hyperpolarization-activated, cyclic nucleotide-gated 2 (HCN2) ion channels that regulate the length of myelin sheaths formed by oligodendrocytes in myelinating cultures and in the mouse brain and spinal cord. These results suggest that the regulation of HCN2 channel activity is well placed to refine sheath length and conduction along myelinated axons, providing a potential mechanism for alterations in conduction velocity and circuit function in response to axonal signals such as those generated by increased activity.
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Affiliation(s)
- Matthew Swire
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, United Kingdom
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
- Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, United Kingdom
| | - Peggy Assinck
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, United Kingdom
| | - Peter A McNaughton
- Wolfson Centre for Age-Related Diseases, King's College London, London WC2R 2LS, United Kingdom
| | - David A Lyons
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
| | - Charles Ffrench-Constant
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, United Kingdom
| | - Matthew R Livesey
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield S10 2HQ, United Kingdom
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26
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Valori CF, Neumann M. Contribution of RNA/DNA Binding Protein Dysfunction in Oligodendrocytes in the Pathogenesis of the Amyotrophic Lateral Sclerosis/Frontotemporal Lobar Degeneration Spectrum Diseases. Front Neurosci 2021; 15:724891. [PMID: 34539339 PMCID: PMC8440855 DOI: 10.3389/fnins.2021.724891] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 07/31/2021] [Indexed: 12/19/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) are two incurable neurodegenerative disorders, often considered as the extreme manifestations of a disease spectrum, as they share similar pathomechanisms. In support of this, pathological aggregation of the RNA/DNA binding proteins trans-activation response element DNA-binding protein 43 (TDP-43) or fused in sarcoma (FUS) is the pathological hallmark found in neurons and glial cells of subsets of patients affected by either condition (i.e., ALS/FTLD—TDP-43 or ALS/FTLD—FUS, respectively). Among glia, oligodendrocytes are the most abundant population, designated to ensheath the axons with myelin and to provide them with metabolic and trophic support. In this minireview, we recapitulate the neuropathological evidence for oligodendroglia impairment in ALS/FTLD. We then debate how TDP-43 and FUS target oligodendrocyte transcripts, thereby controlling their homeostatic abilities toward the axons. Finally, we discuss cellular and animal models aimed at investigating the functional consequences of manipulating TDP-43 and FUS in oligodendrocytes in vivo. Taken together, current data provide increasing evidence for an important role of TDP-43 and FUS-mediated oligodendroglia dysfunction in the pathogenesis of ALS/FTLD. Thus, targeting disrupted oligodendroglial functions may represent a new treatment approach for these conditions.
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Affiliation(s)
- Chiara F Valori
- Molecular Neuropathology of Neurodegenerative Diseases, German Center for Neurodegenerative Diseases, Tübingen, Germany
| | - Manuela Neumann
- Molecular Neuropathology of Neurodegenerative Diseases, German Center for Neurodegenerative Diseases, Tübingen, Germany.,Department of Neuropathology, University Hospital of Tübingen, Tübingen, Germany
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27
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Peric M, Nikolic L, Andjus PR, Bataveljic D. Dysfunction of oligodendrocyte inwardly rectifying potassium channel in a rat model of amyotrophic lateral sclerosis. Eur J Neurosci 2021; 54:6339-6354. [PMID: 34510584 DOI: 10.1111/ejn.15451] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 08/24/2021] [Accepted: 09/05/2021] [Indexed: 01/13/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease caused by the death of motor neurons in the spinal cord and the brain. Although this disease is characterized by motoneuron degeneration, non-neuronal cells such as oligodendrocytes play an important role in the disease onset and progression. The aim of our study was to examine functional properties of oligodendrocytes in the SOD1G93A rat model of ALS with a particular focus on the inwardly rectifying potassium channel Kir4.1 that is abundantly expressed in these glial cells and plays a role in the regulation of extracellular K+ . First, we demonstrate that the expression of Kir4.1 is diminished in the spinal cord oligodendrocytes of the SOD1G93A rat. Moreover, our data show an elevated number of dysmorphic oligodendrocytes in the ALS spinal cord that is indicative of a degenerative phenotype. In order to assess physiological properties of oligodendrocytes, we prepared cell cultures from the rat spinal cord. Oligodendrocytes isolated from the SOD1G93A spinal cord display similar ramification of the processes as the control but express a lower level of Kir4.1. We further demonstrate an impairment of oligodendrocyte functional properties in ALS. Remarkably, whole-cell patch-clamp recordings revealed compromised membrane biophysical properties and diminished inward currents in the SOD1G93A oligodendrocytes. In addition, the Ba2+ -sensitive Kir currents were decreased in ALS oligodendrocytes. Altogether, our findings provide the evidence of impaired Kir4.1 expression and function in oligodendrocytes of the SOD1G93A spinal cord, suggesting oligodendrocyte Kir4.1 channel as a potential contributor to the ALS pathophysiology.
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Affiliation(s)
- Mina Peric
- Institute of Physiology and Biochemistry "Ivan Djaja", Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Ljiljana Nikolic
- Department of Neurophysiology, Institute for Biological Research "Siniša Stanković", National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Pavle R Andjus
- Institute of Physiology and Biochemistry "Ivan Djaja", Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Danijela Bataveljic
- Institute of Physiology and Biochemistry "Ivan Djaja", Faculty of Biology, University of Belgrade, Belgrade, Serbia
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28
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Ion Channels as New Attractive Targets to Improve Re-Myelination Processes in the Brain. Int J Mol Sci 2021; 22:ijms22147277. [PMID: 34298893 PMCID: PMC8305962 DOI: 10.3390/ijms22147277] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 06/28/2021] [Accepted: 07/01/2021] [Indexed: 12/20/2022] Open
Abstract
Multiple sclerosis (MS) is the most demyelinating disease of the central nervous system (CNS) characterized by neuroinflammation. Oligodendrocyte progenitor cells (OPCs) are cycling cells in the developing and adult CNS that, under demyelinating conditions, migrate to the site of lesions and differentiate into mature oligodendrocytes to remyelinate damaged axons. However, this process fails during disease chronicization due to impaired OPC differentiation. Moreover, OPCs are crucial players in neuro-glial communication as they receive synaptic inputs from neurons and express ion channels and neurotransmitter/neuromodulator receptors that control their maturation. Ion channels are recognized as attractive therapeutic targets, and indeed ligand-gated and voltage-gated channels can both be found among the top five pharmaceutical target groups of FDA-approved agents. Their modulation ameliorates some of the symptoms of MS and improves the outcome of related animal models. However, the exact mechanism of action of ion-channel targeting compounds is often still unclear due to the wide expression of these channels on neurons, glia, and infiltrating immune cells. The present review summarizes recent findings in the field to get further insights into physio-pathophysiological processes and possible therapeutic mechanisms of drug actions.
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29
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Boscia F, Elkjaer ML, Illes Z, Kukley M. Altered Expression of Ion Channels in White Matter Lesions of Progressive Multiple Sclerosis: What Do We Know About Their Function? Front Cell Neurosci 2021; 15:685703. [PMID: 34276310 PMCID: PMC8282214 DOI: 10.3389/fncel.2021.685703] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 05/23/2021] [Indexed: 12/19/2022] Open
Abstract
Despite significant advances in our understanding of the pathophysiology of multiple sclerosis (MS), knowledge about contribution of individual ion channels to axonal impairment and remyelination failure in progressive MS remains incomplete. Ion channel families play a fundamental role in maintaining white matter (WM) integrity and in regulating WM activities in axons, interstitial neurons, glia, and vascular cells. Recently, transcriptomic studies have considerably increased insight into the gene expression changes that occur in diverse WM lesions and the gene expression fingerprint of specific WM cells associated with secondary progressive MS. Here, we review the ion channel genes encoding K+, Ca2+, Na+, and Cl- channels; ryanodine receptors; TRP channels; and others that are significantly and uniquely dysregulated in active, chronic active, inactive, remyelinating WM lesions, and normal-appearing WM of secondary progressive MS brain, based on recently published bulk and single-nuclei RNA-sequencing datasets. We discuss the current state of knowledge about the corresponding ion channels and their implication in the MS brain or in experimental models of MS. This comprehensive review suggests that the intense upregulation of voltage-gated Na+ channel genes in WM lesions with ongoing tissue damage may reflect the imbalance of Na+ homeostasis that is observed in progressive MS brain, while the upregulation of a large number of voltage-gated K+ channel genes may be linked to a protective response to limit neuronal excitability. In addition, the altered chloride homeostasis, revealed by the significant downregulation of voltage-gated Cl- channels in MS lesions, may contribute to an altered inhibitory neurotransmission and increased excitability.
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Affiliation(s)
- Francesca Boscia
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, University of Naples "Federico II", Naples, Italy
| | - Maria Louise Elkjaer
- Neurology Research Unit, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Zsolt Illes
- Neurology Research Unit, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Department of Neurology, Odense University Hospital, Odense, Denmark
| | - Maria Kukley
- Achucarro Basque Center for Neuroscience, Leioa, Spain.,Ikerbasque Basque Foundation for Science, Bilbao, Spain
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30
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Cruz-Herranz A, Oertel FC, Kim K, Cantó E, Timmons G, Sin JH, Devereux M, Baker N, Michel B, Schubert RD, Rani L, Cordano C, Baranzini SE, Green AJ. Distinctive waves of innate immune response in the retina in experimental autoimmune encephalomyelitis. JCI Insight 2021; 6:e149228. [PMID: 34100385 PMCID: PMC8262300 DOI: 10.1172/jci.insight.149228] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 04/28/2021] [Indexed: 12/27/2022] Open
Abstract
Neurodegeneration mediates neurological disability in inflammatory demyelinating diseases of the CNS. The role of innate immune cells in mediating this damage has remained controversial with evidence for destructive and protective effects. This has complicated efforts to develop treatment. The time sequence and dynamic evolution of the opposing functions are especially unclear. Given limits of in vivo monitoring in human diseases such as multiple sclerosis (MS), animal models are warranted to investigate the association and timing of innate immune activation with neurodegeneration. Using noninvasive in vivo retinal imaging of experimental autoimmune encephalitis (EAE) in CX3CR1GFP/+–knock-in mice followed by transcriptional profiling, we are able to show 2 distinct waves separated by a marked reduction in the number of innate immune cells and change in cell morphology. The first wave is characterized by an inflammatory phagocytic phenotype preceding the onset of EAE, whereas the second wave is characterized by a regulatory, antiinflammatory phenotype during the chronic stage. Additionally, the magnitude of the first wave is associated with neuronal loss. Two transcripts identified — growth arrest–specific protein 6 (GAS6) and suppressor of cytokine signaling 3 (SOCS3) — might be promising targets for enhancing protective effects of microglia in the chronic phase after initial injury.
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Affiliation(s)
- Andrés Cruz-Herranz
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA
| | - Frederike C Oertel
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA.,Experimental and Clinical Research Center (ECRC), Max-Delbrück-Centrum for Molecular Medicine, and.,NeuroCure Clinical Research Center (NCRC), Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Kicheol Kim
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA
| | - Ester Cantó
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA
| | - Garrett Timmons
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA
| | - Jung H Sin
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA
| | - Michael Devereux
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA
| | - Nicholas Baker
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA
| | - Brady Michel
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA
| | - Ryan D Schubert
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA
| | - Lakshmisahithi Rani
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA
| | - Christian Cordano
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA
| | - Sergio E Baranzini
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA
| | - Ari J Green
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, California, USA.,Department of Ophthalmology, University of California San Francisco, San Francisco, California, USA
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31
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Simkins TJ, Duncan GJ, Bourdette D. Chronic Demyelination and Axonal Degeneration in Multiple Sclerosis: Pathogenesis and Therapeutic Implications. Curr Neurol Neurosci Rep 2021; 21:26. [PMID: 33835275 DOI: 10.1007/s11910-021-01110-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2021] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW Multiple sclerosis (MS) is the most common demyelinating disease of the central nervous system (CNS). Inflammatory attacks in MS lead to both demyelination and axonal damage. However, due to incomplete remyelination most MS lesions remain chronically demyelinated. In parallel, there is axonal degeneration in the CNS of MS patients, contributing to progressive disability. There are currently no approved therapies that adequately restore myelin or protect axons from degeneration. In this review, we will discuss the pathophysiology of axonal loss and chronic demyelination in MS and how understanding this pathophysiology is leading to the development of new MS therapeutics. RECENT FINDINGS Ongoing research into the function of oligodendrocytes and myelin has revealed the importance of their relationship with neuronal health. Demyelination in MS leads to a number of pathophysiologic changes contributing to axonal generation. Among these are mitochondrial dysfunction, persistent neuroinflammation, and the effects of reactive oxygen and nitrogen species. With this information, we review currently approved and investigational therapies designed to restore lost or damaged myelin and protect against neuronal degeneration. The development of therapies to restore lost myelin and protect neurons is a promising avenue of investigation for the benefit of patients with MS.
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Affiliation(s)
- Tyrell J Simkins
- Department of Neurology, Oregon Health and Science University, 3181S W Sam Jackson Rd L226, Portland, OR, 97239, USA. .,Jungers Center for Neurosciences Research, Oregon Health and Science University, Portland, OR, USA. .,Department of Neurology, Portland VA Medical Center, Portland, OR, USA.
| | - Greg J Duncan
- Department of Neurology, Oregon Health and Science University, 3181S W Sam Jackson Rd L226, Portland, OR, 97239, USA.,Jungers Center for Neurosciences Research, Oregon Health and Science University, Portland, OR, USA
| | - Dennis Bourdette
- Department of Neurology, Oregon Health and Science University, 3181S W Sam Jackson Rd L226, Portland, OR, 97239, USA.,Jungers Center for Neurosciences Research, Oregon Health and Science University, Portland, OR, USA
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32
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Marshall-Phelps KLH, Kegel L, Baraban M, Ruhwedel T, Almeida RG, Rubio-Brotons M, Klingseisen A, Benito-Kwiecinski SK, Early JJ, Bin JM, Suminaite D, Livesey MR, Möbius W, Poole RJ, Lyons DA. Neuronal activity disrupts myelinated axon integrity in the absence of NKCC1b. J Cell Biol 2021; 219:151733. [PMID: 32364583 PMCID: PMC7337504 DOI: 10.1083/jcb.201909022] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 03/09/2020] [Accepted: 04/07/2020] [Indexed: 02/07/2023] Open
Abstract
Through a genetic screen in zebrafish, we identified a mutant with disruption to myelin in both the CNS and PNS caused by a mutation in a previously uncharacterized gene, slc12a2b, predicted to encode a Na+, K+, and Cl- (NKCC) cotransporter, NKCC1b. slc12a2b/NKCC1b mutants exhibited a severe and progressive pathology in the PNS, characterized by dysmyelination and swelling of the periaxonal space at the axon-myelin interface. Cell-type-specific loss of slc12a2b/NKCC1b in either neurons or myelinating Schwann cells recapitulated these pathologies. Given that NKCC1 is critical for ion homeostasis, we asked whether the disruption to myelinated axons in slc12a2b/NKCC1b mutants is affected by neuronal activity. Strikingly, we found that blocking neuronal activity completely prevented and could even rescue the pathology in slc12a2b/NKCC1b mutants. Together, our data indicate that NKCC1b is required to maintain neuronal activity-related solute homeostasis at the axon-myelin interface, and the integrity of myelinated axons.
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Affiliation(s)
| | - Linde Kegel
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Marion Baraban
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Torben Ruhwedel
- Electron Microscopy Core Unit, Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Rafael G Almeida
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | | | - Anna Klingseisen
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | | | - Jason J Early
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Jenea M Bin
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Daumante Suminaite
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Matthew R Livesey
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Wiebke Möbius
- Electron Microscopy Core Unit, Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Richard J Poole
- Department of Cell and Developmental Biology, University College London, London, UK
| | - David A Lyons
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
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33
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Duncan GJ, Simkins TJ, Emery B. Neuron-Oligodendrocyte Interactions in the Structure and Integrity of Axons. Front Cell Dev Biol 2021; 9:653101. [PMID: 33763430 PMCID: PMC7982542 DOI: 10.3389/fcell.2021.653101] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 02/15/2021] [Indexed: 12/12/2022] Open
Abstract
The myelination of axons by oligodendrocytes is a highly complex cell-to-cell interaction. Oligodendrocytes and axons have a reciprocal signaling relationship in which oligodendrocytes receive cues from axons that direct their myelination, and oligodendrocytes subsequently shape axonal structure and conduction. Oligodendrocytes are necessary for the maturation of excitatory domains on the axon including nodes of Ranvier, help buffer potassium, and support neuronal energy metabolism. Disruption of the oligodendrocyte-axon unit in traumatic injuries, Alzheimer's disease and demyelinating diseases such as multiple sclerosis results in axonal dysfunction and can culminate in neurodegeneration. In this review, we discuss the mechanisms by which demyelination and loss of oligodendrocytes compromise axons. We highlight the intra-axonal cascades initiated by demyelination that can result in irreversible axonal damage. Both the restoration of oligodendrocyte myelination or neuroprotective therapies targeting these intra-axonal cascades are likely to have therapeutic potential in disorders in which oligodendrocyte support of axons is disrupted.
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Affiliation(s)
- Greg J Duncan
- Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, Portland, OR, United States
| | - Tyrell J Simkins
- Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, Portland, OR, United States.,Vollum Institute, Oregon Health & Science University, Portland, OR, United States.,Department of Neurology, VA Portland Health Care System, Portland, OR, United States
| | - Ben Emery
- Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, Portland, OR, United States
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34
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Schirmer L, Schafer DP, Bartels T, Rowitch DH, Calabresi PA. Diversity and Function of Glial Cell Types in Multiple Sclerosis. Trends Immunol 2021; 42:228-247. [PMID: 33593693 PMCID: PMC7914214 DOI: 10.1016/j.it.2021.01.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 01/04/2021] [Accepted: 01/07/2021] [Indexed: 12/25/2022]
Abstract
Glial subtype diversity is an emerging topic in neurobiology and immune-mediated neurological diseases such as multiple sclerosis (MS). We discuss recent conceptual and technological advances that allow a better understanding of the transcriptomic and functional heterogeneity of oligodendrocytes (OLs), astrocytes, and microglial cells under inflammatory-demyelinating conditions. Recent single cell transcriptomic studies suggest the occurrence of novel homeostatic and reactive glial subtypes and provide insight into the molecular events during disease progression. Multiplexed RNA in situ hybridization has enabled 'mapping back' dysregulated gene expression to glial subtypes within the MS lesion microenvironment. These findings suggest novel homeostatic and reactive glial-cell-type functions both in immune-related processes and neuroprotection relevant to understanding the pathology of MS.
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Affiliation(s)
- Lucas Schirmer
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany; Center for Translational Neuroscience and Institute for Innate Immunoscience, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany; Interdisciplinary Center for Neurosciences, Heidelberg University, Heidelberg, Germany.
| | - Dorothy P Schafer
- Department of Neurobiology and the Brudnik Neuropsychiatric Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Theresa Bartels
- Department of Paediatrics, Wellcome - MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - David H Rowitch
- Department of Paediatrics, Wellcome - MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK; Departments of Pediatrics and Neurosurgery, Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
| | - Peter A Calabresi
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA; Solomon H. Snyder Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, USA.
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35
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Pease-Raissi SE, Chan JR. Building a (w)rapport between neurons and oligodendroglia: Reciprocal interactions underlying adaptive myelination. Neuron 2021; 109:1258-1273. [PMID: 33621477 DOI: 10.1016/j.neuron.2021.02.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/12/2021] [Accepted: 01/29/2021] [Indexed: 12/27/2022]
Abstract
Myelin, multilayered lipid-rich membrane extensions formed by oligodendrocytes around neuronal axons, is essential for fast and efficient action potential propagation in the central nervous system. Initially thought to be a static and immutable process, myelination is now appreciated to be a dynamic process capable of responding to and modulating neuronal function throughout life. While the importance of this type of plasticity, called adaptive myelination, is now well accepted, we are only beginning to understand the underlying cellular and molecular mechanisms by which neurons communicate experience-driven circuit activation to oligodendroglia and precisely how changes in oligodendrocytes and their myelin refine neuronal function. Here, we review recent findings addressing this reciprocal relationship in which neurons alter oligodendroglial form and oligodendrocytes conversely modulate neuronal function.
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Affiliation(s)
- Sarah E Pease-Raissi
- Weill Institute for Neuroscience, Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA.
| | - Jonah R Chan
- Weill Institute for Neuroscience, Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA.
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36
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de Curtis M, Garbelli R, Uva L. A hypothesis for the role of axon demyelination in seizure generation. Epilepsia 2021; 62:583-595. [PMID: 33493363 DOI: 10.1111/epi.16824] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 01/04/2021] [Accepted: 01/05/2021] [Indexed: 01/06/2023]
Abstract
Loss of myelin and altered oligodendrocyte distribution in the cerebral cortex are commonly observed both in postsurgical tissue derived from different focal epilepsies (such as focal cortical dysplasias and tuberous sclerosis) and in animal models of focal epilepsy. Moreover, seizures are a frequent symptom in demyelinating diseases, such as multiple sclerosis, and in animal models of demyelination and oligodendrocyte dysfunction. Finally, the excessive activity reported in demyelinated axons may promote hyperexcitability. We hypothesize that the extracellular potassium rise generated during epileptiform activity may be amplified by the presence of axons without appropriate myelin coating and by alterations in oligodendrocyte function. This process could facilitate the triggering of recurrent spontaneous seizures in areas of altered myelination and could result in further demyelination, thus promoting epileptogenesis.
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Affiliation(s)
- Marco de Curtis
- Epilepsy Unit, IRCCS Foundation Carlo Besta Neurological Institute, Milan, Italy
| | - Rita Garbelli
- Epilepsy Unit, IRCCS Foundation Carlo Besta Neurological Institute, Milan, Italy
| | - Laura Uva
- Epilepsy Unit, IRCCS Foundation Carlo Besta Neurological Institute, Milan, Italy
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37
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Göppner C, Soria AH, Hoegg-Beiler MB, Jentsch TJ. Cellular basis of ClC-2 Cl - channel-related brain and testis pathologies. J Biol Chem 2021; 296:100074. [PMID: 33187987 PMCID: PMC7949093 DOI: 10.1074/jbc.ra120.016031] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 11/11/2020] [Accepted: 11/13/2020] [Indexed: 12/11/2022] Open
Abstract
The ClC-2 chloride channel is expressed in the plasma membrane of almost all mammalian cells. Mutations that cause the loss of ClC-2 function lead to retinal and testicular degeneration and leukodystrophy, whereas gain-of-function mutations cause hyperaldosteronism. Leukodystrophy is also observed with a loss of GlialCAM, a cell adhesion molecule that binds to ClC-2 in glia. GlialCAM changes the localization of ClC-2 and opens the channel by altering its gating. We now used cell type-specific deletion of ClC-2 in mice to show that retinal and testicular degeneration depend on a loss of ClC-2 in retinal pigment epithelial cells and Sertoli cells, respectively, whereas leukodystrophy was fully developed only when ClC-2 was disrupted in both astrocytes and oligodendrocytes. The leukodystrophy of Glialcam-/- mice could not be rescued by crosses with Clcn2op/op mice in which a mutation mimics the "opening" of ClC-2 by GlialCAM. These data indicate that GlialCAM-induced changes in biophysical properties of ClC-2 are irrelevant for GLIALCAM-related leukodystrophy. Taken together, our findings suggest that the pathology caused by Clcn2 disruption results from disturbed extracellular ion homeostasis and identifies the cells involved in this process.
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Affiliation(s)
- Corinna Göppner
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany; Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Audrey H Soria
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany; Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Maja B Hoegg-Beiler
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany; Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Thomas J Jentsch
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany; Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany; NeuroCure Cluster of Excellence, Charité Universitätsmedizin, Berlin, Germany.
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38
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Assembly and Function of the Juxtaparanodal Kv1 Complex in Health and Disease. Life (Basel) 2020; 11:life11010008. [PMID: 33374190 PMCID: PMC7824554 DOI: 10.3390/life11010008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 12/21/2020] [Accepted: 12/23/2020] [Indexed: 02/07/2023] Open
Abstract
The precise axonal distribution of specific potassium channels is known to secure the shape and frequency of action potentials in myelinated fibers. The low-threshold voltage-gated Kv1 channels located at the axon initial segment have a significant influence on spike initiation and waveform. Their role remains partially understood at the juxtaparanodes where they are trapped under the compact myelin bordering the nodes of Ranvier in physiological conditions. However, the exposure of Kv1 channels in de- or dys-myelinating neuropathy results in alteration of saltatory conduction. Moreover, cell adhesion molecules associated with the Kv1 complex, including Caspr2, Contactin2, and LGI1, are target antigens in autoimmune diseases associated with hyperexcitability such as encephalitis, neuromyotonia, or neuropathic pain. The clustering of Kv1.1/Kv1.2 channels at the axon initial segment and juxtaparanodes is based on interactions with cell adhesion molecules and cytoskeletal linkers. This review will focus on the trafficking and assembly of the axonal Kv1 complex in the peripheral and central nervous system (PNS and CNS), during development, and in health and disease.
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39
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Anti-Kir4.1 Antibodies in Multiple Sclerosis: Specificity and Pathogenicity. Int J Mol Sci 2020; 21:ijms21249632. [PMID: 33348803 PMCID: PMC7765826 DOI: 10.3390/ijms21249632] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/14/2020] [Accepted: 12/15/2020] [Indexed: 11/17/2022] Open
Abstract
The glial cells in the central nervous system express diverse inward rectifying potassium channels (Kir). They express multiple Kir channel subtypes that are likely to have distinct functional roles related to their differences in conductance, and sensitivity to intracellular and extracellular factors. Dysfunction in a major astrocyte potassium channel, Kir4.1, appears as an early pathological event underlying neuronal phenotypes in several neurological diseases. The autoimmune effects on the potassium channel have not yet been fully described in the literature. However, several research groups have reported that the potassium channels are an immune target in patients with various neurological disorders. In 2012, Srivastava et al. reported about Kir4.1, a new immune target for autoantibodies in patients with multiple sclerosis (MS). Follow-up studies have been conducted by several research groups, but no clear conclusion has been reached. Most follow-up studies, including ours, have reported that the prevalence of Kir4.1-seropositive patients with MS was lower than that in the initial study. Therefore, we extensively review studies on the method of antibody testing, seroprevalence of MS, and other neurological diseases in patients with MS. Finally, based on the role of Kir4.1 in MS, we consider whether it could be an immune target in this disease.
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Beutel T, Dzimiera J, Kapell H, Engelhardt M, Gass A, Schirmer L. Cortical projection neurons as a therapeutic target in multiple sclerosis. Expert Opin Ther Targets 2020; 24:1211-1224. [PMID: 33103501 DOI: 10.1080/14728222.2020.1842358] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
INTRODUCTION Multiple sclerosis (MS) is a chronic inflammatory-demyelinating disease of the central nervous system associated with lesions of the cortical gray matter and subcortical white matter. Recently, cortical lesions have become a major focus of research because cortical pathology and neuronal damage are critical determinants of irreversible clinical progression. Recent transcriptomic studies point toward cell type-specific changes in cortical neurons in MS with a selective vulnerability of excitatory projection neuron subtypes. AREAS COVERED We discuss the cortical mapping and the molecular properties of excitatory projection neurons and their role in MS lesion pathology while placing an emphasis on their subtype-specific transcriptomic changes and levels of vulnerability. We also examine the latest magnetic resonance imaging techniques to study cortical MS pathology as a key tool for monitoring disease progression and treatment efficacy. Finally, we consider possible therapeutic avenues and novel strategies to protect excitatory cortical projection neurons. Literature search methodology: PubMed articles from 2000-2020. EXPERT OPINION Excitatory cortical projection neurons are an emerging therapeutic target in the treatment of progressive MS. Understanding neuron subtype-specific molecular pathologies and their exact spatial mapping will help establish starting points for the development of novel cell type-specific therapies and biomarkers in MS.
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Affiliation(s)
- Tatjana Beutel
- Department of Neurology, Medical Faculty Mannheim, MCTN, Heidelberg University , Mannheim, Germany
| | - Julia Dzimiera
- Department of Neurology, Medical Faculty Mannheim, MCTN, Heidelberg University , Mannheim, Germany
| | - Hannah Kapell
- Department of Neurology, Medical Faculty Mannheim, MCTN, Heidelberg University , Mannheim, Germany
| | - Maren Engelhardt
- Institute of Neuroanatomy, Medical Faculty Mannheim, MCTN, Heidelberg University , Mannheim, Germany.,Interdisciplinary Center for Neurosciences, Heidelberg University , Heidelberg, Germany
| | - Achim Gass
- Department of Neurology, Medical Faculty Mannheim, MCTN, Heidelberg University , Mannheim, Germany
| | - Lucas Schirmer
- Department of Neurology, Medical Faculty Mannheim, MCTN, Heidelberg University , Mannheim, Germany.,Interdisciplinary Center for Neurosciences, Heidelberg University , Heidelberg, Germany
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Xin W, Chan JR. Myelin plasticity: sculpting circuits in learning and memory. Nat Rev Neurosci 2020; 21:682-694. [PMID: 33046886 DOI: 10.1038/s41583-020-00379-8] [Citation(s) in RCA: 128] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/03/2020] [Indexed: 02/06/2023]
Abstract
Throughout our lifespan, new sensory experiences and learning continually shape our neuronal circuits to form new memories. Plasticity at the level of synapses has been recognized and studied for decades, but recent work has revealed an additional form of plasticity - affecting oligodendrocytes and the myelin sheaths they produce - that plays a crucial role in learning and memory. In this Review, we summarize recent work characterizing plasticity in the oligodendrocyte lineage following sensory experience and learning, the physiological and behavioural consequences of manipulating that plasticity, and the evidence for oligodendrocyte and myelin dysfunction in neurodevelopmental disorders with cognitive symptoms. We also discuss the limitations of existing approaches and the conceptual and technical advances that are needed to move forward this rapidly developing field.
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Affiliation(s)
- Wendy Xin
- Weill Institute for Neuroscience, Department of Neurology, University of California, San Francisco, San Francisco, CA, USA.
| | - Jonah R Chan
- Weill Institute for Neuroscience, Department of Neurology, University of California, San Francisco, San Francisco, CA, USA.
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Lubetzki C, Zalc B, Williams A, Stadelmann C, Stankoff B. Remyelination in multiple sclerosis: from basic science to clinical translation. Lancet Neurol 2020; 19:678-688. [PMID: 32702337 DOI: 10.1016/s1474-4422(20)30140-x] [Citation(s) in RCA: 170] [Impact Index Per Article: 42.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 04/03/2020] [Accepted: 04/09/2020] [Indexed: 01/19/2023]
Abstract
The treatment of multiple sclerosis has been transformed by the successful development of immunotherapies that efficiently reduce disease activity and related clinical relapses during the relapsing-remitting phase of the disease. However, the prevention of disability progression, which is due to axonal and neuronal damage and loss, has yet to be achieved and is therapeutically challenging, particularly during the progressive phase of the disease. One strategy to counteract neurodegeneration is to promote neuroprotection by enhancing myelin regeneration, hence restoring nerve conduction and metabolic support to the axon. Animal studies have provided targets for interventions to improve brain and spinal cord remyelination, paving the way for the translation of this research to humans. From these initial and promising forays, further problems have emerged, including questions on how best to design these clinical trials and appropriately measure the outcomes. Solving these problems will need additional work before efficacious pro-remyelination therapies will be ready for people with multiple sclerosis, but there is a real sense of hope that researchers are getting closer to a successful therapy.
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Affiliation(s)
- Catherine Lubetzki
- Sorbonne University, Institut National de la Santé et de la Recherche Médicale (INSERM), Centre National de la Recherche Scientifique (CNRS), Institut du Cerveau (ICM), Groupe Hospitalier APHP-Sorbonne University, Paris, France; Neurology Department Pitié-Salpêtrière, Groupe Hospitalier APHP-Sorbonne University, Paris, France.
| | - Bernard Zalc
- Sorbonne University, Institut National de la Santé et de la Recherche Médicale (INSERM), Centre National de la Recherche Scientifique (CNRS), Institut du Cerveau (ICM), Groupe Hospitalier APHP-Sorbonne University, Paris, France
| | - Anna Williams
- Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, UK
| | - Christine Stadelmann
- Institute of Neuropathology, University Medical Center Göttingen, Göttingen, Germany
| | - Bruno Stankoff
- Sorbonne University, Institut National de la Santé et de la Recherche Médicale (INSERM), Centre National de la Recherche Scientifique (CNRS), Institut du Cerveau (ICM), Groupe Hospitalier APHP-Sorbonne University, Paris, France; Neurology Department Saint-Antoine, Groupe Hospitalier APHP-Sorbonne University, Paris, France
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Boni JL, Kahanovitch U, Nwaobi SE, Floyd CL, Olsen ML. DNA methylation: A mechanism for sustained alteration of KIR4.1 expression following central nervous system insult. Glia 2020; 68:1495-1512. [PMID: 32068308 PMCID: PMC8665281 DOI: 10.1002/glia.23797] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 01/29/2020] [Accepted: 01/31/2020] [Indexed: 12/22/2022]
Abstract
Kir4.1, a glial-specific inwardly rectifying potassium channel, is implicated in astrocytic maintenance of K+ homeostasis. Underscoring the role of Kir4.1 in central nervous system (CNS) functioning, genetic mutations in KCNJ10, the gene which encodes Kir4.1, causes seizures, ataxia and developmental disability in humans. Kir4.1 protein and mRNA loss are consistently observed in CNS injury and neurological diseases linked to hyperexcitability and neuronal dysfunction, leading to the notion that Kir4.1 represents an attractive therapeutic target. Despite this, little is understood regarding the mechanisms that underpin this downregulation. Previous work by our lab revealed that DNA hypomethylation of the Kcnj10 gene functions to regulate mRNA levels during astrocyte maturation whereas hypermethylation in vitro led to decreased promoter activity. In the present study, we utilized two vastly different injury models with known acute and chronic loss of Kir4.1 protein and mRNA to evaluate the methylation status of Kcnj10 as a candidate molecular mechanism for reduced transcription and subsequent protein loss. Examining whole hippocampal tissue and isolated astrocytes, in a lithium-pilocarpine model of epilepsy, we consistently identified hypermethylation of CpG island two, which resides in the large intronic region spanning the Kcnj10 gene. Strikingly similar results were observed using the second injury paradigm, a fifth cervical (C5) vertebral hemi-contusion model of spinal cord injury. Our previous work indicates the same gene region is significantly hypomethylated when transcription increases during astrocyte maturation. Our results suggest that DNA methylation can bidirectionally modulate Kcnj10 transcription and may represent a targetable molecular mechanism for the restoring astroglial Kir4.1 expression following CNS insult.
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Affiliation(s)
- Jessica L Boni
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
- School of Neuroscience, Virginia Polytechnic and State University, Blacksburg, Virginia
| | - Uri Kahanovitch
- School of Neuroscience, Virginia Polytechnic and State University, Blacksburg, Virginia
| | - Sinifunanya E Nwaobi
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
- Division of Pediatric Neurology, UCLA Mattel Children's Hospital, University of California Los Angeles, Los Angeles, California
| | - Candace L Floyd
- Department of Physical Medicine and Rehabilitation, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Physical Medicine and Rehabilitation, University of Utah Health, Salt Lake City, Utah
| | - Michelle L Olsen
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
- School of Neuroscience, Virginia Polytechnic and State University, Blacksburg, Virginia
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Kessi M, Chen B, Peng J, Tang Y, Olatoutou E, He F, Yang L, Yin F. Intellectual Disability and Potassium Channelopathies: A Systematic Review. Front Genet 2020; 11:614. [PMID: 32655623 PMCID: PMC7324798 DOI: 10.3389/fgene.2020.00614] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 05/20/2020] [Indexed: 01/15/2023] Open
Abstract
Intellectual disability (ID) manifests prior to adulthood as severe limitations to intellectual function and adaptive behavior. The role of potassium channelopathies in ID is poorly understood. Therefore, we aimed to evaluate the relationship between ID and potassium channelopathies. We hypothesized that potassium channelopathies are strongly associated with ID initiation, and that both gain- and loss-of-function mutations lead to ID. This systematic review explores the burden of potassium channelopathies, possible mechanisms, advancements using animal models, therapies, and existing gaps. The literature search encompassed both PubMed and Embase up to October 2019. A total of 75 articles describing 338 cases were included in this review. Nineteen channelopathies were identified, affecting the following genes: KCNMA1, KCNN3, KCNT1, KCNT2, KCNJ10, KCNJ6, KCNJ11, KCNA2, KCNA4, KCND3, KCNH1, KCNQ2, KCNAB1, KCNQ3, KCNQ5, KCNC1, KCNB1, KCNC3, and KCTD3. Twelve of these genes presented both gain- and loss-of-function properties, three displayed gain-of-function only, three exhibited loss-of-function only, and one had unknown function. How gain- and loss-of-function mutations can both lead to ID remains largely unknown. We identified only a few animal studies that focused on the mechanisms of ID in relation to potassium channelopathies and some of the few available therapeutic options (channel openers or blockers) appear to offer limited efficacy. In conclusion, potassium channelopathies contribute to the initiation of ID in several instances and this review provides a comprehensive overview of which molecular players are involved in some of the most prominent disease phenotypes.
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Affiliation(s)
- Miriam Kessi
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China.,Kilimanjaro Christian Medical University College, Moshi, Tanzania.,Mawenzi Regional Referral Hospital, Moshi, Tanzania
| | - Baiyu Chen
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Yulin Tang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Eleonore Olatoutou
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Fang He
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Lifen Yang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
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Correale J, Marrodan M, Benarroch EE. What is the role of axonal ion channels in multiple sclerosis? Neurology 2020; 95:120-123. [PMID: 32482838 DOI: 10.1212/wnl.0000000000009754] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Affiliation(s)
- Jorge Correale
- From the Department of Neurology (J.C., M.M.), Fleni, Buenos Aires, Argentina; and Department of Neurology (E.E.B.), Mayo Clinic, Rochester, MN.
| | - Mariano Marrodan
- From the Department of Neurology (J.C., M.M.), Fleni, Buenos Aires, Argentina; and Department of Neurology (E.E.B.), Mayo Clinic, Rochester, MN
| | - Eduardo E Benarroch
- From the Department of Neurology (J.C., M.M.), Fleni, Buenos Aires, Argentina; and Department of Neurology (E.E.B.), Mayo Clinic, Rochester, MN
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Yool AJ, Ramesh S. Molecular Targets for Combined Therapeutic Strategies to Limit Glioblastoma Cell Migration and Invasion. Front Pharmacol 2020; 11:358. [PMID: 32292341 PMCID: PMC7118801 DOI: 10.3389/fphar.2020.00358] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 03/10/2020] [Indexed: 12/21/2022] Open
Abstract
The highly invasive nature of glioblastoma imposes poor prospects for patient survival. Molecular evidence indicates glioblastoma cells undergo an intriguing expansion of phenotypic properties to include neuron-like signaling using excitable membrane ion channels and synaptic proteins, augmenting survival and motility. Neurotransmitter receptors, membrane signaling, excitatory receptors, and Ca2+ responses are important candidates for the design of customized treatments for cancers within the heterogeneous central nervous system. Relatively few published studies of glioblastoma multiforme (GBM) have evaluated pharmacological agents targeted to signaling pathways in limiting cancer cell motility. Transcriptomic analyses here identified classes of ion channels, ionotropic receptors, and synaptic proteins that are enriched in human glioblastoma biopsy samples. The pattern of GBM-enriched gene expression points to a major role for glutamate signaling. However, the predominant role of AMPA receptors in fast excitatory signaling throughout the central nervous system raises a challenge on how to target inhibitors selectively to cancer cells while maintaining tolerability. This review critically evaluates a panel of ligand- and voltage-gated ion channels and synaptic proteins upregulated in GBM, and the evidence for their potential roles in the pathological disease progress. Evidence suggests combinations of therapies could be more effective than single agents alone. Natural plant products used in traditional medicines for the treatment of glioblastoma contain flavonoids, terpenoids, polyphenols, epigallocatechin gallate, quinones, and saponins, which might serendipitously include agents that modulate some classes of signaling compounds highlighted in this review. New therapeutic strategies are likely to exploit evidence-based combinations of selected agents, each at a low dose, to create new cancer cell-specific therapeutics.
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Affiliation(s)
- Andrea J. Yool
- Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Sunita Ramesh
- Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
- College of Science and Engineering, Flinders University, Adelaide, SA, Australia
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47
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Zhang J, Han J, Li L, Zhang Q, Feng Y, Jiang Y, Deng F, Zhang Y, Wu Q, Chen B, Hu J. Inwardly rectifying potassium channel 5.1: Structure, function, and possible roles in diseases. Genes Dis 2020; 8:272-278. [PMID: 33997174 PMCID: PMC8093645 DOI: 10.1016/j.gendis.2020.03.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 03/02/2020] [Accepted: 03/13/2020] [Indexed: 11/30/2022] Open
Abstract
Inwardly rectifying potassium (Kir) channels make it easier for K+ to enter into a cell and subsequently regulate cellular biological functions. Kir5.1 (encoded by KCNJ16) alone can form a homotetramer and can form heterotetramers with Kir4.1 (encoded by KCNJ10) or Kir4.2 (encoded by KCNJ15). In most cases, homomeric Kir5.1 is non-functional, while heteromeric Kir5.1 on the cell membrane contributes to the inward flow of K+ ions, which can be regulated by intracellular pH and a variety of signaling mechanisms. In the form of a heterotetramer, Kir5.1 regulates Kir4.1/4.2 activity and is involved in the maintenance of nephron function. Actually, homomeric Kir5.1 may also play a very important role in diseases, including in the ventilatory response to hypoxia and hypercapnia, hearing impairment, cardiovascular disease and cancer. With an increase in the number of studies into the roles of Kir channels, researchers are paying more attention to the pathophysiological functions of Kir5.1. This minireview provides an overview regarding these Kir5.1 roles.
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Affiliation(s)
- Junhui Zhang
- Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, PR China.,State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, PR China.,Department of Endocrinology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, PR China
| | - Jian Han
- Department of Obstetrics and Gynecology, Daping Hospital, Third Military Medical University (Army Medical University), Chongqing, 400042, PR China
| | - Lingfei Li
- Department of Dermatology, Daping Hospital, Third Military Medical University (Army Medical University), Chongqing, 400042, PR China
| | - Qiong Zhang
- Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, PR China.,State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, PR China
| | - Yanhai Feng
- Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, PR China.,State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, PR China
| | - Youzhao Jiang
- Department of Endocrinology, People's Hospital of Banan District, Chongqing, 401320, PR China
| | - Fang Deng
- Department of Endocrinology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, PR China
| | - Yuping Zhang
- Department of Endocrinology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, PR China
| | - Qinan Wu
- Department of Endocrinology, Chongqing Cancer Hospital (Chongqing University Cancer Hospital), Chongqing, 40030, PR China
| | - Bing Chen
- Department of Endocrinology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, PR China
| | - Jiongyu Hu
- Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, PR China.,State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, PR China.,Department of Endocrinology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, PR China
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Papanikolaou M, Butt AM, Lewis A. A critical role for the inward rectifying potassium channel Kir7.1 in oligodendrocytes of the mouse optic nerve. Brain Struct Funct 2020; 225:925-934. [PMID: 32086565 PMCID: PMC7166203 DOI: 10.1007/s00429-020-02043-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 02/06/2020] [Indexed: 01/27/2023]
Abstract
Inward rectifying potassium channels (Kir) are a large family of ion channels that play key roles in ion homeostasis in oligodendrocytes, the myelinating cells of the central nervous system (CNS). Prominent expression of Kir4.1 has been indicated in oligodendrocytes, but the extent of expression of other Kir subtypes is unclear. Here, we used qRT-PCR to determine expression of Kir channel transcripts in the mouse optic nerve, a white matter tract comprising myelinated axons and the glia that support them. A novel finding was the high relative expression of Kir7.1, comparable to that of Kir4.1, the main glial Kir channel. Significantly, Kir7.1 immunofluorescence labelling in optic nerve sections and in isolated cells was localised to oligodendrocyte somata. Kir7.1 are known as a K+ transporting channels and, using patch clamp electrophysiology and the Kir7.1 blocker VU590, we demonstrated Kir7.1 channels carry a significant proportion of the whole cell potassium conductance in oligodendrocytes isolated from mouse optic nerves. Notably, oligodendrocytes are highly susceptible to ischemia/hypoxia and this is due at least in part to disruption of ion homeostasis. A key finding of this study is that blockade of Kir7.1 with VU590 compromised oligodendrocyte cell integrity and compounds oligodendroglial loss in ischemia/hypoxia in the oxygen-glucose deprivation (OGD) model in isolated intact optic nerves. These data reveal Kir7.1 channels are molecularly and functionally expressed in oligodendrocytes and play an important role in determining oligodendrocyte survival and myelin integrity.
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Affiliation(s)
- Maria Papanikolaou
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, PO1 2DT, UK
| | - Arthur M Butt
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, PO1 2DT, UK.
| | - Anthony Lewis
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, PO1 2DT, UK
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Abstract
Cells of the oligodendrocyte lineage express a wide range of Ca2+ channels and receptors that regulate oligodendrocyte progenitor cell (OPC) and oligodendrocyte formation and function. Here we define those key channels and receptors that regulate Ca2+ signaling and OPC development and myelination. We then discuss how the regulation of intracellular Ca2+ in turn affects OPC and oligodendrocyte biology in the healthy nervous system and under pathological conditions. Activation of Ca2+ channels and receptors in OPCs and oligodendrocytes by neurotransmitters converges on regulating intracellular Ca2+, making Ca2+ signaling a central candidate mediator of activity-driven myelination. Indeed, recent evidence indicates that localized changes in Ca2+ in oligodendrocytes can regulate the formation and remodeling of myelin sheaths and perhaps additional functions of oligodendrocytes and OPCs. Thus, decoding how OPCs and myelinating oligodendrocytes integrate and process Ca2+ signals will be important to fully understand central nervous system formation, health, and function.
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Affiliation(s)
- Pablo M Paez
- Department of Pharmacology and Toxicology and Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences, The State University of New York, University at Buffalo, Buffalo, New York 14203, USA;
| | - David A Lyons
- Centre for Discovery Brain Sciences, Centre for Multiple Sclerosis Research, and Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh EH16 4SB, United Kingdom;
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50
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Cohen CCH, Popovic MA, Klooster J, Weil MT, Möbius W, Nave KA, Kole MHP. Saltatory Conduction along Myelinated Axons Involves a Periaxonal Nanocircuit. Cell 2020; 180:311-322.e15. [PMID: 31883793 PMCID: PMC6978798 DOI: 10.1016/j.cell.2019.11.039] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 08/24/2019] [Accepted: 11/27/2019] [Indexed: 11/30/2022]
Abstract
The propagation of electrical impulses along axons is highly accelerated by the myelin sheath and produces saltating or "jumping" action potentials across internodes, from one node of Ranvier to the next. The underlying electrical circuit, as well as the existence and role of submyelin conduction in saltatory conduction remain, however, elusive. Here, we made patch-clamp and high-speed voltage-calibrated optical recordings of potentials across the nodal and internodal axolemma of myelinated neocortical pyramidal axons combined with electron microscopy and experimentally constrained cable modeling. Our results reveal a nanoscale yet conductive periaxonal space, incompletely sealed at the paranodes, which separates the potentials across the low-capacitance myelin sheath and internodal axolemma. The emerging double-cable model reproduces the recorded evolution of voltage waveforms across nodes and internodes, including rapid nodal potentials traveling in advance of attenuated waves in the internodal axolemma, revealing a mechanism for saltation across time and space.
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Affiliation(s)
- Charles C H Cohen
- Department of Axonal Signalling, Netherlands Institute for Neuroscience, Royal Netherlands Academy for Arts and Sciences, Meibergdreef 47, 1105 BA Amsterdam, the Netherlands; Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands
| | - Marko A Popovic
- Department of Axonal Signalling, Netherlands Institute for Neuroscience, Royal Netherlands Academy for Arts and Sciences, Meibergdreef 47, 1105 BA Amsterdam, the Netherlands
| | - Jan Klooster
- Department of Axonal Signalling, Netherlands Institute for Neuroscience, Royal Netherlands Academy for Arts and Sciences, Meibergdreef 47, 1105 BA Amsterdam, the Netherlands
| | - Marie-Theres Weil
- Department of Neurogenetics, Max-Planck-Institute for Experimental Medicine, Göttingen, Hermann-Rein-Strasse 3, 37075 Göttingen, Germany; Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
| | - Wiebke Möbius
- Department of Neurogenetics, Max-Planck-Institute for Experimental Medicine, Göttingen, Hermann-Rein-Strasse 3, 37075 Göttingen, Germany; Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
| | - Klaus-Armin Nave
- Department of Neurogenetics, Max-Planck-Institute for Experimental Medicine, Göttingen, Hermann-Rein-Strasse 3, 37075 Göttingen, Germany; Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
| | - Maarten H P Kole
- Department of Axonal Signalling, Netherlands Institute for Neuroscience, Royal Netherlands Academy for Arts and Sciences, Meibergdreef 47, 1105 BA Amsterdam, the Netherlands; Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands.
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