1
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Barragan EV, Anisimova M, Vijayakumar V, Coblentz A, Park DK, Salaka RJ, Nisan AFK, Petshow S, Dore K, Zito K, Gray JA. d-Serine Inhibits Non-ionotropic NMDA Receptor Signaling. J Neurosci 2024; 44:e0140242024. [PMID: 38942470 PMCID: PMC11308331 DOI: 10.1523/jneurosci.0140-24.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 05/24/2024] [Accepted: 06/25/2024] [Indexed: 06/30/2024] Open
Abstract
NMDA-type glutamate receptors (NMDARs) are widely recognized as master regulators of synaptic plasticity, most notably for driving long-term changes in synapse size and strength that support learning. NMDARs are unique among neurotransmitter receptors in that they require binding of both neurotransmitter (glutamate) and co-agonist (e.g., d-serine) to open the receptor channel, which leads to the influx of calcium ions that drive synaptic plasticity. Over the past decade, evidence has accumulated that NMDARs also support synaptic plasticity via ion flux-independent (non-ionotropic) signaling upon the binding of glutamate in the absence of co-agonist, although conflicting results have led to significant controversy. Here, we hypothesized that a major source of contradictory results might be attributed to variable occupancy of the co-agonist binding site under different experimental conditions. To test this hypothesis, we manipulated co-agonist availability in acute hippocampal slices from mice of both sexes. We found that enzymatic scavenging of endogenous co-agonists enhanced the magnitude of long-term depression (LTD) induced by non-ionotropic NMDAR signaling in the presence of the NMDAR pore blocker MK801. Conversely, a saturating concentration of d-serine completely inhibited LTD and spine shrinkage induced by glutamate binding in the presence of MK801 or Mg2+ Using a Förster resonance energy transfer (FRET)-based assay in cultured neurons, we further found that d-serine completely blocked NMDA-induced conformational movements of the GluN1 cytoplasmic domains in the presence of MK801. Our results support a model in which d-serine availability serves to modulate NMDAR signaling and synaptic plasticity even when the NMDAR is blocked by magnesium.
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Affiliation(s)
- Eden V Barragan
- Center for Neuroscience, University of California, Davis, California 95618
| | - Margarita Anisimova
- Center for Neuroscience, University of California, Davis, California 95618
- Departments of Neurobiology, Physiology and Behavior, University of California, Davis, California 95618
| | - Vishnu Vijayakumar
- Center for Neural Circuits and Behavior, Department of Neuroscience and Section for Neurobiology, Division of Biology, University of California at San Diego, San Diego, California 92093
| | - Azariah Coblentz
- Center for Neuroscience, University of California, Davis, California 95618
- Departments of Neurobiology, Physiology and Behavior, University of California, Davis, California 95618
| | - Deborah K Park
- Center for Neuroscience, University of California, Davis, California 95618
- Departments of Neurobiology, Physiology and Behavior, University of California, Davis, California 95618
| | - Raghava Jagadeesh Salaka
- Center for Neuroscience, University of California, Davis, California 95618
- Neurology, University of California, Davis, California 95618
| | - Atheer F K Nisan
- Center for Neuroscience, University of California, Davis, California 95618
| | - Samuel Petshow
- Center for Neuroscience, University of California, Davis, California 95618
- Departments of Neurobiology, Physiology and Behavior, University of California, Davis, California 95618
| | - Kim Dore
- Center for Neural Circuits and Behavior, Department of Neuroscience and Section for Neurobiology, Division of Biology, University of California at San Diego, San Diego, California 92093
| | - Karen Zito
- Center for Neuroscience, University of California, Davis, California 95618
- Departments of Neurobiology, Physiology and Behavior, University of California, Davis, California 95618
| | - John A Gray
- Center for Neuroscience, University of California, Davis, California 95618
- Neurology, University of California, Davis, California 95618
- Psychiatry and Behavioral Sciences, University of California, Davis, California 95618
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2
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Gall CM, Le AA, Lynch G. Contributions of site- and sex-specific LTPs to everyday memory. Philos Trans R Soc Lond B Biol Sci 2024; 379:20230223. [PMID: 38853551 DOI: 10.1098/rstb.2023.0223] [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: 10/23/2023] [Accepted: 03/06/2024] [Indexed: 06/11/2024] Open
Abstract
Commentaries about long-term potentiation (LTP) generally proceed with an implicit assumption that largely the same physiological effect is sampled across different experiments. However, this is clearly not the case. We illustrate the point by comparing LTP in the CA3 projections to CA1 with the different forms of potentiation in the dentate gyrus. These studies lead to the hypothesis that specialized properties of CA1-LTP are adaptations for encoding unsupervised learning and episodic memory, whereas the dentate gyrus variants subserve learning that requires multiple trials and separation of overlapping bodies of information. Recent work has added sex as a second and somewhat surprising dimension along which LTP is also differentiated. Triggering events for CA1-LTP differ between the sexes and the adult induction threshold is significantly higher in females; these findings help explain why males have an advantage in spatial learning. Remarkably, the converse is true before puberty: Females have the lower LTP threshold and are better at spatial memory problems. A mechanism has been identified for the loss-of-function in females but not for the gain-of-function in males. We propose that the many and disparate demands of natural environments, with different processing requirements across ages and between sexes, led to the emergence of multiple LTPs. This article is part of a discussion meeting issue 'Long-term potentiation: 50 years on'.
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Affiliation(s)
- Christine M Gall
- Department of Anatomy and Neurobiology, University of California at Irvine , Irvine, CA 92697, USA
- Department of Neurobiology and Behavior, University of California at Irvine , Irvine, CA 92697, USA
| | - Aliza A Le
- Department of Anatomy and Neurobiology, University of California at Irvine , Irvine, CA 92697, USA
| | - Gary Lynch
- Department of Anatomy and Neurobiology, University of California at Irvine , Irvine, CA 92697, USA
- Department of Psychiatry and Human Behavior, University of California at Irvine , Irvine, CA 92868, USA
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3
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Dunot J, Moreno S, Gandin C, Pousinha PA, Amici M, Dupuis J, Anisimova M, Winschel A, Uriot M, Petshow SJ, Mensch M, Bethus I, Giudici C, Hampel H, Wefers B, Wurst W, Naumann R, Ashby MC, Laube B, Zito K, Mellor JR, Groc L, Willem M, Marie H. APP fragment controls both ionotropic and non-ionotropic signaling of NMDA receptors. Neuron 2024:S0896-6273(24)00404-5. [PMID: 38878768 DOI: 10.1016/j.neuron.2024.05.027] [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: 07/26/2023] [Revised: 04/09/2024] [Accepted: 05/29/2024] [Indexed: 07/20/2024]
Abstract
NMDA receptors (NMDARs) are ionotropic receptors crucial for brain information processing. Yet, evidence also supports an ion-flux-independent signaling mode mediating synaptic long-term depression (LTD) and spine shrinkage. Here, we identify AETA (Aη), an amyloid-β precursor protein (APP) cleavage product, as an NMDAR modulator with the unique dual regulatory capacity to impact both signaling modes. AETA inhibits ionotropic NMDAR activity by competing with the co-agonist and induces an intracellular conformational modification of GluN1 subunits. This favors non-ionotropic NMDAR signaling leading to enhanced LTD and favors spine shrinkage. Endogenously, AETA production is increased by in vivo chemogenetically induced neuronal activity. Genetic deletion of AETA production alters NMDAR transmission and prevents LTD, phenotypes rescued by acute exogenous AETA application. This genetic deletion also impairs contextual fear memory. Our findings demonstrate AETA-dependent NMDAR activation (ADNA), characterizing AETA as a unique type of endogenous NMDAR modulator that exerts bidirectional control over NMDAR signaling and associated information processing.
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Affiliation(s)
- Jade Dunot
- Université Côte d'Azur, CNRS, INSERM, Institut de Pharmacologie Moléculaire et Cellulaire, 06560 Valbonne, France; Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| | - Sebastien Moreno
- Université Côte d'Azur, CNRS, INSERM, Institut de Pharmacologie Moléculaire et Cellulaire, 06560 Valbonne, France
| | - Carine Gandin
- Université Côte d'Azur, CNRS, INSERM, Institut de Pharmacologie Moléculaire et Cellulaire, 06560 Valbonne, France
| | - Paula A Pousinha
- Université Côte d'Azur, CNRS, INSERM, Institut de Pharmacologie Moléculaire et Cellulaire, 06560 Valbonne, France
| | - Mascia Amici
- Centre for Synaptic Plasticity, School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol BS8 1TD, UK
| | - Julien Dupuis
- Université de Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, 33076 Bordeaux Cedex, France
| | - Margarita Anisimova
- Center for Neuroscience, University of California, Davis, Davis, CA 95618, USA
| | - Alex Winschel
- Department of Biology, Neurophysiology und Neurosensory Systems, TU Darmstadt, 64287 Darmstadt, Germany
| | - Magalie Uriot
- Université de Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, 33076 Bordeaux Cedex, France
| | - Samuel J Petshow
- Center for Neuroscience, University of California, Davis, Davis, CA 95618, USA
| | - Maria Mensch
- Université Côte d'Azur, CNRS, INSERM, Institut de Pharmacologie Moléculaire et Cellulaire, 06560 Valbonne, France
| | - Ingrid Bethus
- Université Côte d'Azur, CNRS, INSERM, Institut de Pharmacologie Moléculaire et Cellulaire, 06560 Valbonne, France
| | - Camilla Giudici
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany
| | - Heike Hampel
- Biomedical Center (BMC), Division of Metabolic Biochemistry, Faculty of Medicine, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Benedikt Wefers
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany; Institute of Developmental Genetics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Wolfgang Wurst
- Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany; German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany; Institute of Developmental Genetics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Ronald Naumann
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Michael C Ashby
- Centre for Synaptic Plasticity, School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol BS8 1TD, UK
| | - Bodo Laube
- Department of Biology, Neurophysiology und Neurosensory Systems, TU Darmstadt, 64287 Darmstadt, Germany
| | - Karen Zito
- Center for Neuroscience, University of California, Davis, Davis, CA 95618, USA
| | - Jack R Mellor
- Centre for Synaptic Plasticity, School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol BS8 1TD, UK
| | - Laurent Groc
- Université de Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, 33076 Bordeaux Cedex, France
| | - Michael Willem
- Biomedical Center (BMC), Division of Metabolic Biochemistry, Faculty of Medicine, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.
| | - Hélène Marie
- Université Côte d'Azur, CNRS, INSERM, Institut de Pharmacologie Moléculaire et Cellulaire, 06560 Valbonne, France.
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4
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Barragan EV, Anisimova M, Vijayakumar V, Coblentz AC, Park DK, Salaka RJ, Nisan AFK, Petshow S, Dore K, Zito K, Gray JA. D-Serine inhibits non-ionotropic NMDA receptor signaling. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.29.596266. [PMID: 38854020 PMCID: PMC11160797 DOI: 10.1101/2024.05.29.596266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
NMDA-type glutamate receptors (NMDARs) are widely recognized as master regulators of synaptic plasticity, most notably for driving long-term changes in synapse size and strength that support learning. NMDARs are unique among neurotransmitter receptors in that they require binding of both neurotransmitter (glutamate) and co-agonist (e.g. d -serine) to open the receptor channel, which leads to the influx of calcium ions that drive synaptic plasticity. Over the past decade, evidence has accumulated that NMDARs also support synaptic plasticity via ion flux-independent (non-ionotropic) signaling upon the binding of glutamate in the absence of co-agonist, although conflicting results have led to significant controversy. Here, we hypothesized that a major source of contradictory results can be attributed to variable occupancy of the co-agonist binding site under different experimental conditions. To test this hypothesis, we manipulated co-agonist availability in acute hippocampal slices from mice of both sexes. We found that enzymatic scavenging of endogenous co-agonists enhanced the magnitude of LTD induced by non-ionotropic NMDAR signaling in the presence of the NMDAR pore blocker, MK801. Conversely, a saturating concentration of d -serine completely inhibited both LTD and spine shrinkage induced by glutamate binding in the presence of MK801. Using a FRET-based assay in cultured neurons, we further found that d -serine completely blocked NMDA-induced conformational movements of the GluN1 cytoplasmic domains in the presence of MK801. Our results support a model in which d -serine inhibits ion flux-independent NMDAR signaling and plasticity, and thus d -serine availability could serve to modulate NMDAR signaling even when the NMDAR is blocked by magnesium. Significance Statement NMDARs are glutamate-gated cation channels that are key regulators of neurodevelopment and synaptic plasticity and unique in their requirement for binding of a co-agonist (e.g. d -serine) in order for the channel to open. NMDARs have been found to drive synaptic plasticity via non-ionotropic (ion flux-independent) signaling upon the binding of glutamate in the absence of co-agonist, though conflicting results have led to controversy. Here, we found that d -serine inhibits non-ionotropic NMDAR-mediated LTD and LTD-associated spine shrinkage. Thus, a major source of the contradictory findings might be attributed to experimental variability in d -serine availability. In addition, the developmental regulation of d -serine levels suggests a role for non-ionotropic NMDAR plasticity during critical periods of plasticity.
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5
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Brunetti V, Soda T, Berra-Romani R, De Sarro G, Guerra G, Scarpellino G, Moccia F. Two Signaling Modes Are Better than One: Flux-Independent Signaling by Ionotropic Glutamate Receptors Is Coming of Age. Biomedicines 2024; 12:880. [PMID: 38672234 PMCID: PMC11048239 DOI: 10.3390/biomedicines12040880] [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: 03/07/2024] [Revised: 04/02/2024] [Accepted: 04/12/2024] [Indexed: 04/28/2024] Open
Abstract
Glutamate is the major excitatory neurotransmitter in the central nervous system. Glutamatergic transmission can be mediated by ionotropic glutamate receptors (iGluRs), which mediate rapid synaptic depolarization that can be associated with Ca2+ entry and activity-dependent change in the strength of synaptic transmission, as well as by metabotropic glutamate receptors (mGluRs), which mediate slower postsynaptic responses through the recruitment of second messenger systems. A wealth of evidence reported over the last three decades has shown that this dogmatic subdivision between iGluRs and mGluRs may not reflect the actual physiological signaling mode of the iGluRs, i.e., α-amino-3-hydroxy-5-methyl-4-isoxasolepropionic acid (AMPA) receptors (AMPAR), kainate receptors (KARs), and N-methyl-D-aspartate (NMDA) receptors (NMDARs). Herein, we review the evidence available supporting the notion that the canonical iGluRs can recruit flux-independent signaling pathways not only in neurons, but also in brain astrocytes and cerebrovascular endothelial cells. Understanding the signaling versatility of iGluRs can exert a profound impact on our understanding of glutamatergic synapses. Furthermore, it may shed light on novel neuroprotective strategies against brain disorders.
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Affiliation(s)
- Valentina Brunetti
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, 27110 Pavia, Italy; (V.B.); (G.S.)
| | - Teresa Soda
- Department of Health Sciences, School of Medicine and Surgery, Magna Graecia University of Catanzaro, 88100 Catanzaro, Italy; (T.S.); (G.D.S.)
| | - Roberto Berra-Romani
- Department of Biomedicine, School of Medicine, Benemérita Universidad Autónoma de Puebla, Puebla 72410, Mexico;
| | - Giovambattista De Sarro
- Department of Health Sciences, School of Medicine and Surgery, Magna Graecia University of Catanzaro, 88100 Catanzaro, Italy; (T.S.); (G.D.S.)
- System and Applied Pharmacology@University Magna Grecia, Science of Health Department, School of Medicine, Magna Graecia University of Catanzaro, 88110 Catanzaro, Italy
| | - Germano Guerra
- Department of Medicine and Health Science “Vincenzo Tiberio”, School of Medicine and Surgery, University of Molise, 86100 Campobasso, Italy;
| | - Giorgia Scarpellino
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, 27110 Pavia, Italy; (V.B.); (G.S.)
| | - Francesco Moccia
- Department of Medicine and Health Science “Vincenzo Tiberio”, School of Medicine and Surgery, University of Molise, 86100 Campobasso, Italy;
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6
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Mony L, Paoletti P. Mechanisms of NMDA receptor regulation. Curr Opin Neurobiol 2023; 83:102815. [PMID: 37988826 DOI: 10.1016/j.conb.2023.102815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 10/31/2023] [Accepted: 10/31/2023] [Indexed: 11/23/2023]
Abstract
N-methyl-D-aspartate receptors (NMDARs) are glutamate-gated ion channels widely expressed in the central nervous system that play key role in brain development and plasticity. On the downside, NMDAR dysfunction, be it hyperactivity or hypofunction, is harmful to neuronal function and has emerged as a common theme in various neuropsychiatric disorders including autism spectrum disorders, epilepsy, intellectual disability, and schizophrenia. Not surprisingly, NMDAR signaling is under a complex set of regulatory mechanisms that maintain NMDAR-mediated transmission in check. These include an unusual large number of endogenous agents that directly bind NMDARs and tune their activity in a subunit-dependent manner. Here, we review current knowledge on the regulation of NMDAR signaling. We focus on the regulation of the receptor by its microenvironment as well as by external (i.e. pharmacological) factors and their underlying molecular and cellular mechanisms. Recent developments showing how NMDAR dysregulation participate to disease mechanisms are also highlighted.
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Affiliation(s)
- Laetitia Mony
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, Université PSL, CNRS, INSERM, F-75005 Paris, France.
| | - Pierre Paoletti
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, Université PSL, CNRS, INSERM, F-75005 Paris, France.
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7
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Larsen ME, Buonarati OR, Qian H, Hell JW, Bayer KU. Stimulating β-adrenergic receptors promotes synaptic potentiation by switching CaMKII movement from LTD to LTP mode. J Biol Chem 2023; 299:104706. [PMID: 37061000 PMCID: PMC10200978 DOI: 10.1016/j.jbc.2023.104706] [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: 09/21/2022] [Revised: 03/31/2023] [Accepted: 04/06/2023] [Indexed: 04/17/2023] Open
Abstract
Learning, memory, and cognition are thought to require synaptic plasticity, specifically including hippocampal long-term potentiation and depression (LTP and LTD). LTP versus LTD is induced by high-frequency stimulation versus low-frequency, but stimulating β-adrenergic receptors (βARs) enables LTP induction also by low-frequency stimulation (1 Hz) or theta frequencies (∼5 Hz) that do not cause plasticity by themselves. In contrast to high-frequency stimulation-LTP, such βAR-LTP requires Ca2+-flux through L-type voltage-gated Ca2+-channels, not N-methyl-D-aspartate-type glutamate receptors. Surprisingly, we found that βAR-LTP still required a nonionotropic scaffolding function of the N-methyl-D-aspartate-type glutamate receptor: the stimulus-induced binding of the Ca2+/calmodulin-dependent protein kinase II (CaMKII) to its GluN2B subunit that mediates CaMKII movement to excitatory synapses. In hippocampal neurons, β-adrenergic stimulation with isoproterenol (Iso) transformed LTD-type CaMKII movement to LTP-type movement, resulting in CaMKII movement to excitatory instead of inhibitory synapses. Additionally, Iso enabled induction of a major cell-biological feature of LTP in response to LTD stimuli: increased surface expression of GluA1 fused with super-ecliptic pHluorein. Like for βAR-LTP in hippocampal slices, the Iso effects on CaMKII movement and surface expression of GluA1 fused with super-ecliptic pHluorein involved L-type Ca2+-channels and specifically required β2-ARs. Taken together, these results indicate that Iso transforms LTD stimuli to LTP signals by switching CaMKII movement and GluN2B binding to LTP mode.
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Affiliation(s)
- Matthew E Larsen
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA; Program in Neuroscience, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Olivia R Buonarati
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Hai Qian
- Department of Pharmacology, University of Iowa, Iowa City, Iowa, USA
| | - Johannes W Hell
- Department of Pharmacology, University of Iowa, Iowa City, Iowa, USA; Department of Pharmacology, University of California at Davis, Davis, California, USA.
| | - K Ulrich Bayer
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA; Program in Neuroscience, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
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8
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Chen H, Dong Y, Wu Y, Yi F. Targeting NMDA receptor signaling for therapeutic intervention in brain disorders. Rev Neurosci 2023:revneuro-2022-0096. [PMID: 36586105 DOI: 10.1515/revneuro-2022-0096] [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: 07/31/2022] [Accepted: 12/03/2022] [Indexed: 01/01/2023]
Abstract
N-Methyl-d-aspartate (NMDA) receptor hyperfunction plays a key role in the pathological processes of depression and neurodegenerative diseases, whereas NMDA receptor hypofunction is implicated in schizophrenia. Considerable efforts have been made to target NMDA receptor function for the therapeutic intervention in those brain disorders. In this mini-review, we first discuss ion flux-dependent NMDA receptor signaling and ion flux-independent NMDA receptor signaling that result from structural rearrangement upon binding of endogenous agonists. Then, we review current strategies for exploring druggable targets of the NMDA receptor signaling and promising future directions, which are poised to result in new therapeutic agents for several brain disorders.
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Affiliation(s)
- He Chen
- Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Southern Medical University, Guangzhou 510515, P. R. China
| | - Yuanping Dong
- Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Southern Medical University, Guangzhou 510515, P. R. China
| | - Yun Wu
- Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Southern Medical University, Guangzhou 510515, P. R. China
| | - Feng Yi
- Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Southern Medical University, Guangzhou 510515, P. R. China
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9
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Temmermand R, Barrett JE, Fontana ACK. Glutamatergic systems in neuropathic pain and emerging non-opioid therapies. Pharmacol Res 2022; 185:106492. [PMID: 36228868 PMCID: PMC10413816 DOI: 10.1016/j.phrs.2022.106492] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 10/05/2022] [Accepted: 10/06/2022] [Indexed: 01/14/2023]
Abstract
Neuropathic pain, a disease of the somatosensory nervous system, afflicts many individuals and adequate management with current pharmacotherapies remains elusive. The glutamatergic system of neurons, receptors and transporters are intimately involved in pain but, to date, there have been few drugs developed that therapeutically modulate this system. Glutamate transporters, or excitatory amino acid transporters (EAATs), remove excess glutamate around pain transmitting neurons to decrease nociception suggesting that the modulation of glutamate transporters may represent a novel approach to the treatment of pain. This review highlights and summarizes (1) the physiology of the glutamatergic system in neuropathic pain, (2) the preclinical evidence for dysregulation of glutamate transport in animal pain models, and (3) emerging novel therapies that modulate glutamate transporters. Successful drug discovery requires continuous focus on basic and translational methods to fully elucidate the etiologies of this disease to enable the development of targeted therapies. Increasing the efficacy of astrocytic EAATs may serve as a new way to successfully treat those suffering from this devastating disease.
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Affiliation(s)
- Rhea Temmermand
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - James E Barrett
- Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA
| | - Andréia C K Fontana
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102, USA.
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10
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Wang B, Zou L, Zhou L. Lipid bilayers regulate allosteric signal of NMDA receptor GluN1 C-terminal domain. Biochem Biophys Res Commun 2021; 585:15-21. [PMID: 34781056 DOI: 10.1016/j.bbrc.2021.11.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 11/02/2021] [Indexed: 11/30/2022]
Abstract
NMDAR (N-methyl-d-aspartate receptor) consisted of GluN1 and GluN2, and/or GluN3 subunits. As the obligatory subunit of NMDAR, GluN1 contains variant N-terminal domain (NTD) and C-terminal domain (CTD). The CTD contains allosteric signal and mediates the metabotropic function of NMDAR, which has been confirmed by previous studies. However, the allosteric signaling mechanism of GluN1 CTD has not been studied. In our study, we found that GluN1 CTD could bind to the lipid bilayers and affect the antigen epitope of GluN1 C-terminal antibody, suggesting that membrane binding may determine the allosteric signal of GluN1 CTD. In addition, we discovered that the membrane binding of GluN1 CTD could be regulated by the phosphorylation of GluN1 CTD C1 region.
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Affiliation(s)
- Busong Wang
- College of Pharmaceutical Sciences, Soochow University, 199 Renai Road, Suzhou, 215123, Jiangsu, China
| | - Lu Zou
- College of Pharmaceutical Sciences, Soochow University, 199 Renai Road, Suzhou, 215123, Jiangsu, China
| | - Liang Zhou
- College of Pharmaceutical Sciences, Soochow University, 199 Renai Road, Suzhou, 215123, Jiangsu, China.
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11
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NMDA receptors elicit flux-independent intracellular Ca 2+ signals via metabotropic glutamate receptors and flux-dependent nitric oxide release in human brain microvascular endothelial cells. Cell Calcium 2021; 99:102454. [PMID: 34454368 DOI: 10.1016/j.ceca.2021.102454] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 07/28/2021] [Accepted: 08/12/2021] [Indexed: 12/20/2022]
Abstract
The excitatory neurotransmitter glutamate gates post-synaptic N-methyl-d-aspartate (NMDA) receptors (NMDARs) to mediate extracellular Ca2+ entry and stimulate neuronal nitric oxide (NO) synthase to release NO and trigger neurovascular coupling (NVC). Neuronal and glial NMDARs may also operate in a flux-independent manner, although it is unclear whether their non-ionotropic mode of action is involved in NVC. Recently, endothelial NMDARs were found to trigger Ca2+-dependent NO production and induce NVC, but the underlying mode of signaling remains elusive. Herein, we report that GluN1 protein, as well as GluN2C and GluN3B transcripts and proteins, were expressed and that NMDA did not elicit inward currents, but induced a dose-dependent increase in intracellular Ca2+ concentration ([Ca2+]i) in the human brain microvascular endothelial cell line, hCMEC/D3. A multidisciplinary approach, including live cell imaging, whole-cell patch-clamp recordings, pharmacological manipulation and gene targeting, revealed that NMDARs increase the [Ca2+]i in a flux-independent manner in hCMEC/D3 cells. The Ca2+ response to NMDA was triggered by endogenous Ca2+ release from the endoplasmic reticulum and the lysosomal Ca2+ stores and sustained by store-operated Ca2+ entry. Unexpectedly, pharmacological and genetic blockade of mGluR1 and mGluR5 dramatically impaired NMDARs-mediated Ca2+ signals. These findings indicate that NMDARs may increase the endothelial [Ca2+]i in a flux-independent manner via group 1 mGluRs. However, imaging of DAF-FM fluorescence revealed that NMDARs may also induce Ca2+-dependent NO release by signaling in a flux-dependent manner. These findings, therefore, shed novel light on the mechanisms whereby brain microvascular endothelium decodes glutamatergic signaling and regulates NVC.
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12
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Stroebel D, Mony L, Paoletti P. Glycine agonism in ionotropic glutamate receptors. Neuropharmacology 2021; 193:108631. [PMID: 34058193 DOI: 10.1016/j.neuropharm.2021.108631] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/21/2021] [Accepted: 05/23/2021] [Indexed: 12/12/2022]
Abstract
Ionotropic glutamate receptors (iGluRs) are ligand-gated ion channels that mediate the majority of excitatory neurotransmission in the vertebrate CNS. Classified as AMPA, kainate, delta and NMDA receptors, iGluRs are central drivers of synaptic plasticity widely considered as a major cellular substrate of learning and memory. Surprisingly however, five out of the eighteen vertebrate iGluR subunits do not bind glutamate but glycine, a neurotransmitter known to mediate inhibitory neurotransmission through its action on pentameric glycine receptors (GlyRs). This is the case of GluN1, GluN3A, GluN3B, GluD1 and GluD2 subunits, all also binding the D amino acid d-serine endogenously present in many brain regions. Glycine and d-serine action and affinities broadly differ between glycinergic iGluR subtypes. On 'conventional' GluN1/GluN2 NMDA receptors, glycine (or d-serine) acts in concert with glutamate as a mandatory co-agonist to set the level of receptor activity. It also regulates the receptor's trafficking and expression independently of glutamate. On 'unconventional' GluN1/GluN3 NMDARs, glycine acts as the sole agonist directly triggering opening of excitatory glycinergic channels recently shown to be physiologically relevant. On GluD receptors, d-serine on its own mediates non-ionotropic signaling involved in excitatory and inhibitory synaptogenesis, further reinforcing the concept of glutamate-insensitive iGluRs. Here we present an overview of our current knowledge on glycine and d-serine agonism in iGluRs emphasizing aspects related to molecular mechanisms, cellular function and pharmacological profile. The growing appreciation of the critical influence of glycine and d-serine on iGluR biology reshapes our understanding of iGluR signaling diversity and complexity, with important implications in neuropharmacology.
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Affiliation(s)
- David Stroebel
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, Université PSL, CNRS, INSERM, F-75005, Paris, France.
| | - Laetitia Mony
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, Université PSL, CNRS, INSERM, F-75005, Paris, France
| | - Pierre Paoletti
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, Université PSL, CNRS, INSERM, F-75005, Paris, France.
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13
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Petit-Pedrol M, Groc L. Regulation of membrane NMDA receptors by dynamics and protein interactions. J Cell Biol 2021; 220:211609. [PMID: 33337489 PMCID: PMC7754687 DOI: 10.1083/jcb.202006101] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 11/19/2020] [Accepted: 11/20/2020] [Indexed: 12/16/2022] Open
Abstract
Understanding neurotransmitter system crosstalk in the brain is a major challenge in neurobiology. Several intracellular and genomic cascades have been identified in this crosstalk. However, the discovery that neurotransmitter receptors are highly diffusive in the plasma membrane of neurons, where they form heterocomplexes with other proteins, has profoundly changed our view of neurotransmitter signaling. Here, we review new insights into neurotransmitter crosstalk at the plasma membrane. We focus on the membrane organization and interactome of the ionotropic glutamate N-methyl-D-aspartate receptor (NMDAR) that plays a central role in excitatory synaptic and network physiology and is involved in the etiology of several major neuropsychiatric disorders. The nanoscale organization and dynamics of NMDAR is a key regulatory process for glutamate synapse transmission, plasticity, and crosstalk with other neurotransmitter systems, such as the monoaminergic ones. The plasma membrane appears to be a prime regulatory compartment for spatial and temporal crosstalk between neurotransmitter systems in the healthy and diseased brain. Understanding the molecular mechanisms regulating membrane neurotransmitter receptor crosstalk will likely open research avenues for innovative therapeutical strategies.
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Affiliation(s)
- Mar Petit-Pedrol
- Université de Bordeaux, Centre National de la Recherche Scientifique, Interdisciplinary Institute for Neuroscience, Unité Mixte de Recherche 5297, Bordeaux, France
| | - Laurent Groc
- Université de Bordeaux, Centre National de la Recherche Scientifique, Interdisciplinary Institute for Neuroscience, Unité Mixte de Recherche 5297, Bordeaux, France
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14
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Moreno A. Molecular mechanisms of forgetting. Eur J Neurosci 2020; 54:6912-6932. [DOI: 10.1111/ejn.14839] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 04/23/2020] [Accepted: 05/18/2020] [Indexed: 11/30/2022]
Affiliation(s)
- Andrea Moreno
- Danish Institute of Translational Neuroscience (DANDRITE) Aarhus University Aarhus C Denmark
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15
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Liu J, Chang L, Song Y, Li H, Wu Y. The Role of NMDA Receptors in Alzheimer's Disease. Front Neurosci 2019; 13:43. [PMID: 30800052 PMCID: PMC6375899 DOI: 10.3389/fnins.2019.00043] [Citation(s) in RCA: 234] [Impact Index Per Article: 46.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 01/16/2019] [Indexed: 12/13/2022] Open
Abstract
In Alzheimer’s disease (AD), early synaptic dysfunction is associated with the increased oligomeric amyloid-beta peptide, which causes NMDAR-dependent synaptic depression and spine elimination. Memantine, low-affinity NMDAR channel blocker, has been used in the treatment of moderate to severe AD. However, clear evidence is still deficient in demonstrating the underlying mechanisms and a relationship between NMDARs dysfunction and AD. This review focuses on not only changes in expression of different NMDAR subunits, but also some unconventional modes of NMDAR action.
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Affiliation(s)
- Jinping Liu
- School of Medicine, Tsinghua University, Beijing, China
| | - Lirong Chang
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Yizhi Song
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Hui Li
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Yan Wu
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
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16
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Minnella AM, Zhao JX, Jiang X, Jakobsen E, Lu F, Wu L, El-Benna J, Gray JA, Swanson RA. Excitotoxic superoxide production and neuronal death require both ionotropic and non-ionotropic NMDA receptor signaling. Sci Rep 2018; 8:17522. [PMID: 30504838 PMCID: PMC6269523 DOI: 10.1038/s41598-018-35725-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 11/07/2018] [Indexed: 12/12/2022] Open
Abstract
NMDA-type glutamate receptors (NMDAR) trigger superoxide production by neuronal NADPH oxidase-2 (NOX2), which if sustained leads to cell death. This process involves Ca2+ influx through NMDAR channels. By contrast, comparable Ca2+ influx by other routes does not induce NOX2 activation or cell death. This contrast has been attributed to site-specific effects of Ca2+ flux through NMDAR. Here we show instead that it stems from non-ionotropic signaling by NMDAR GluN2B subunits. To evaluate non-ionotropic effects, mouse cortical neurons were treated with NMDA together with 7-chlorokynurenate, L-689,560, or MK-801, which block Ca2+ influx through NMDAR channels but not NMDA binding. NMDA-induced superoxide formation was prevented by the channel blockers, restored by concurrent Ca2+ influx through ionomycin or voltage-gated calcium channels, and not induced by the Ca2+ influx in the absence of NMDAR ligand binding. Neurons expressing either GluN2B subunits or chimeric GluN2A/GluN2B C-terminus subunits exhibited NMDA-induced superoxide production, whereas neurons expressing chimeric GluN2B/GluN2A C-terminus subunits did not. Neuronal NOX2 activation requires phosphoinositide 3-kinase (PI3K), and NMDA binding to NMDAR increased PI3K association with NMDA GluN2B subunits independent of Ca2+ influx. These findings identify a non-ionotropic signaling pathway that links NMDAR to NOX2 activation through the C-terminus domain of GluN2B.
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Affiliation(s)
- Angela M Minnella
- Department of Neurology, University of California, San Francisco, San Francisco, CA, 94122, USA.,San Francisco Veterans Affairs Medical Center, San Francisco, CA, 94121, USA
| | - Jerry X Zhao
- Department of Neurology, University of California, San Francisco, San Francisco, CA, 94122, USA.,San Francisco Veterans Affairs Medical Center, San Francisco, CA, 94121, USA
| | - Xiangning Jiang
- Department of Pediatrics, University of California, San Francisco, San Francisco, CA, 94143, USA
| | - Emil Jakobsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Fuxin Lu
- Department of Pediatrics, University of California, San Francisco, San Francisco, CA, 94143, USA
| | - Long Wu
- Department of Neurology, University of California, San Francisco, San Francisco, CA, 94122, USA.,San Francisco Veterans Affairs Medical Center, San Francisco, CA, 94121, USA
| | - Jamel El-Benna
- INSERM-U1149, CNRS-ERL8252, Centre de Recherche sur l'Inflammation, Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, Laboratoire d'Excellence Inflamex, Faculté de Médecine, Site Xavier Bichat, Paris, France
| | - John A Gray
- Center for Neuroscience and Department of Neurology, University of California Davis, Davis, CA, 95618, USA
| | - Raymond A Swanson
- Department of Neurology, University of California, San Francisco, San Francisco, CA, 94122, USA. .,San Francisco Veterans Affairs Medical Center, San Francisco, CA, 94121, USA.
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17
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Montes de Oca Balderas P. Flux-Independent NMDAR Signaling: Molecular Mediators, Cellular Functions, and Complexities. Int J Mol Sci 2018; 19:ijms19123800. [PMID: 30501045 PMCID: PMC6321296 DOI: 10.3390/ijms19123800] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 11/16/2018] [Accepted: 11/19/2018] [Indexed: 12/21/2022] Open
Abstract
The glutamate (Glu) N-methyl-d-aspartate (NMDA) receptor (NMDAR) plays a critical role in synaptic communication given mainly by its ionotropic function that permeates Ca2+. This in turn activates calmodulin that triggers CaMKII, MAPK, CREB, and PI3K pathways, among others. However, NMDAR signaling is more complex. In the last two decades several groups have shown that the NMDAR also elicits flux-independent signaling (f-iNMDARs). It has been demonstrated that agonist (Glu or NMDA) or co-agonist (Glycine or d-Serine) bindings initiate intracellular events, including conformational changes, exchange of molecular interactions, release of second messengers, and signal transduction, that result in different cellular events including endocytosis, LTD, cell death, and neuroprotection, among others. Interestingly, f-iNMDARs has also been observed in pathological conditions and non-neuronal cells. Here, the molecular and cellular events elicited by these flux-independent actions (non-canonical or metabotropic-like) of the NMDAR are reviewed. Considering the NMDAR complexity, it is possible that these flux-independent events have a more relevant role in intracellular signaling that has been disregarded for decades. Moreover, considering the wide expression and function of the NMDAR in non-neuronal cells and other tissues beyond the nervous system and some evolutionary traits, f-iNMDARs calls for a reconsideration of how we understand the biology of this complex receptor.
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Affiliation(s)
- Pavel Montes de Oca Balderas
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, UNAM. Av. Universidad 3000, C.U. Coyoacán, Ciudad de México. C.P. 04510, Mexico.
- Unidad de Neurobiología Dinámica, Departamento de Neuroquímica, INNN. Av. Insurgentes Sur #3877 Col. La Fama, Ciudad de México. C.P. 14269, Mexico.
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18
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Long-Term Depression Is Independent of GluN2 Subunit Composition. J Neurosci 2018; 38:4462-4470. [PMID: 29593052 DOI: 10.1523/jneurosci.0394-18.2018] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 03/16/2018] [Accepted: 03/20/2018] [Indexed: 11/21/2022] Open
Abstract
NMDA receptors (NMDARs) mediate both long-term potentiation and long-term depression (LTD) and understanding how a single receptor can initiate both phenomena remains a major question in neuroscience. A prominent hypothesis implicates the NMDAR subunit composition, specifically GluN2A and GluN2B, in dictating the rules of synaptic plasticity. However, studies testing this hypothesis have yielded inconsistent and often contradictory results, especially for LTD. These inconsistent results may be due to challenges in the interpretation of subunit-selective pharmacology and in dissecting out the contributions of differential channel properties versus the interacting proteins unique to GluN2A or GluN2B. In this study, we address the pharmacological and biochemical challenges by using a single-neuron genetic approach to delete NMDAR subunits in conditional knock-out mice. In addition, the recently discovered non-ionotropic nature of NMDAR-dependent LTD allowed the rigorous assessment of unique subunit contributions to NMDAR-dependent LTD while eliminating the variable of differential charge transfer. Here we find that neither the GluN2A nor the GluN2B subunit is strictly necessary for either non-ionotropic or ionotropic LTD.SIGNIFICANCE STATEMENT NMDA receptors are key regulators of bidirectional synaptic plasticity. Understanding the mechanisms regulating bidirectional plasticity will guide development of therapeutic strategies to treat the dysfunctional synaptic plasticity in multiple neuropsychiatric disorders. Because of the unique properties of the NMDA receptor GluN2 subunits, they have been postulated to differentially affect synaptic plasticity. However, there has been significant controversy regarding the roles of the GluN2 subunits in synaptic long term depression (LTD). Using single-neuron knock-out of the GluN2 subunits, we show that LTD requires neither GluN2A nor GluN2B.
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19
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O'Riordan KJ, Hu NW, Rowan MJ. Physiological activation of mGlu5 receptors supports the ion channel function of NMDA receptors in hippocampal LTD induction in vivo. Sci Rep 2018. [PMID: 29535352 PMCID: PMC5849730 DOI: 10.1038/s41598-018-22768-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Synaptic long-term depression (LTD) is believed to underlie critical mnemonic processes in the adult hippocampus. The roles of the metabotropic and ionotropic actions of glutamate in the induction of synaptic LTD by electrical low-frequency stimulation (LFS) in the living adult animal is poorly understood. Here we examined the requirement for metabotropic glutamate (mGlu) and NMDA receptors in LTD induction in anaesthetized adult rats. LTD induction was primarily dependent on NMDA receptors and required the involvement of both the ion channel function and GluN2B subunit of the receptor. Endogenous mGlu5 receptor activation necessitated the local application of relatively high doses of either competitive or non-competitive NMDA receptor antagonists to block LTD induction. Moreover, boosting endogenous glutamate activation of mGlu5 receptors with a positive allosteric modulator lowered the threshold for NMDA receptor-dependent LTD induction by weak LFS. The present data provide support in the living animal that NMDA receptor-dependent LTD is boosted by endogenously released glutamate activation of mGlu5 receptors. Given the predominant perisynaptic location of mGlu5 receptors, the present findings emphasize the need to further evaluate the contribution and mechanisms of these receptors in NMDA receptor-dependent synaptic plasticity in the adult hippocampus in vivo.
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Affiliation(s)
- Kenneth J O'Riordan
- Department of Pharmacology and Therapeutics and Institute of Neuroscience, Watts Building, Trinity College, Dublin, 2, Ireland
| | - Neng-Wei Hu
- Department of Pharmacology and Therapeutics and Institute of Neuroscience, Watts Building, Trinity College, Dublin, 2, Ireland. .,Department of Gerontology, Yijishan Hospital, Wannan Medical College, Wuhu, China. .,Department of Physiology and Neurobiology, Zhengzhou University School of Medicine, Zhengzhou, 450001, China.
| | - Michael J Rowan
- Department of Pharmacology and Therapeutics and Institute of Neuroscience, Watts Building, Trinity College, Dublin, 2, Ireland.
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20
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Torres L, Robinson SA, Kim DG, Yan A, Cleland TA, Bynoe MS. Toxoplasma gondii alters NMDAR signaling and induces signs of Alzheimer's disease in wild-type, C57BL/6 mice. J Neuroinflammation 2018; 15:57. [PMID: 29471842 PMCID: PMC5824585 DOI: 10.1186/s12974-018-1086-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 02/01/2018] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Alzheimer's disease (AD) is a progressive neurodegenerative disease associated with cognitive decline and complete loss of basic functions. The ubiquitous apicomplexan parasite Toxoplasma gondii (T. gondii) infects up to one third of the world's population and is implicated in AD. METHODS We infected C57BL/6 wild-type male and female mice with 10 T. gondii ME49 cysts and assessed whether infection led to behavioral and anatomical effects using immunohistochemistry, immunofluorescence, Western blotting, cell culture assays, as well as an array of mouse behavior tests. RESULTS We show that T. gondii infection induced two major hallmarks of AD in the brains of C57BL/6 male and female mice: beta-amyloid (Aβ) immunoreactivity and hyperphosphorylated Tau. Infected mice showed significant neuronal death, loss of N-methyl-D-aspartate receptor (NMDAR) expression, and loss of olfactory sensory neurons. T. gondii infection also caused anxiety-like behavior, altered recognition of social novelty, altered spatial memory, and reduced olfactory sensitivity. This last finding was exclusive to male mice, as infected females showed intact olfactory sensitivity. CONCLUSIONS These results demonstrate that T. gondii can induce advanced signs of AD in wild-type mice and that it may induce AD in some individuals with underlying health problems.
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Affiliation(s)
- Luisa Torres
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Sudie-Ann Robinson
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Do-Geun Kim
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Angela Yan
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Thomas A Cleland
- Department of Psychology, Cornell University, Ithaca, NY, 14853, USA
| | - Margaret S Bynoe
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA.
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21
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Valbuena S, Lerma J. Non-canonical Signaling, the Hidden Life of Ligand-Gated Ion Channels. Neuron 2017; 92:316-329. [PMID: 27764665 DOI: 10.1016/j.neuron.2016.10.016] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 10/03/2016] [Accepted: 10/06/2016] [Indexed: 12/25/2022]
Abstract
Neurotransmitter receptors are responsible for the transfer of information across the synapse. While ionotropic receptors form ion channels and mediate rapid membrane depolarization, so-called metabotropic receptors exert their action though slower, less direct intracellular signaling pathways. Glutamate, GABA, and acetylcholine can activate both ionotropic and metabotropic receptors, yet the distinction between these "canonical" signaling systems has become less clear since ionotropic receptors were proposed to also activate second messenger systems, defining a "non-canonical" signaling pathway. How these alternative pathways affect neuronal circuit activity is not well understood, and their influence could be more significant than previously anticipated. In this review, we examine the evidence available that supports the existence of parallel and unsuspected signaling pathways used by ionotropic neurotransmitter receptors.
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Affiliation(s)
- Sergio Valbuena
- Instituto de Neurociencias CSIC-UMH, 03550 San Juan de Alicante, Spain
| | - Juan Lerma
- Instituto de Neurociencias CSIC-UMH, 03550 San Juan de Alicante, Spain.
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22
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Hansen KB, Yi F, Perszyk RE, Menniti FS, Traynelis SF. NMDA Receptors in the Central Nervous System. Methods Mol Biol 2017; 1677:1-80. [PMID: 28986865 DOI: 10.1007/978-1-4939-7321-7_1] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
NMDA-type glutamate receptors are ligand-gated ion channels that mediate a major component of excitatory neurotransmission in the central nervous system (CNS). They are widely distributed at all stages of development and are critically involved in normal brain functions, including neuronal development and synaptic plasticity. NMDA receptors are also implicated in the pathophysiology of numerous neurological and psychiatric disorders, such as ischemic stroke, traumatic brain injury, Alzheimer's disease, epilepsy, mood disorders, and schizophrenia. For these reasons, NMDA receptors have been intensively studied in the past several decades to elucidate their physiological roles and to advance them as therapeutic targets. Seven NMDA receptor subunits exist that assemble into a diverse array of tetrameric receptor complexes, which are differently regulated, have distinct regional and developmental expression, and possess a wide range of functional and pharmacological properties. The diversity in subunit composition creates NMDA receptor subtypes with distinct physiological roles across neuronal cell types and brain regions, and enables precise tuning of synaptic transmission. Here, we will review the relationship between NMDA receptor structure and function, the diversity and significance of NMDA receptor subtypes in the CNS, as well as principles and rules by which NMDA receptors operate in the CNS under normal and pathological conditions.
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Affiliation(s)
- Kasper B Hansen
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT, USA. .,Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT, USA.
| | - Feng Yi
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT, USA
| | - Riley E Perszyk
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, USA
| | - Frank S Menniti
- MindImmune Therapeutics, Inc., George & Anne Ryan Institute for Neuroscience, Kingston, RI, USA
| | - Stephen F Traynelis
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, USA
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