1
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Domin H, Burnat G. mGlu4R, mGlu7R, and mGlu8R allosteric modulation for treating acute and chronic neurodegenerative disorders. Pharmacol Rep 2024:10.1007/s43440-024-00657-7. [PMID: 39348087 DOI: 10.1007/s43440-024-00657-7] [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: 07/19/2024] [Revised: 09/12/2024] [Accepted: 09/16/2024] [Indexed: 10/01/2024]
Abstract
Neuroprotection, defined as safeguarding neurons from damage and death by inhibiting diverse pathological mechanisms, continues to be a promising approach for managing a range of central nervous system (CNS) disorders, including acute conditions such as ischemic stroke and traumatic brain injury (TBI) and chronic neurodegenerative diseases like Parkinson's disease (PD), Alzheimer's disease (AD), and multiple sclerosis (MS). These pathophysiological conditions involve excessive glutamatergic (Glu) transmission activity, which can lead to excitotoxicity. Inhibiting this excessive Glu transmission has been proposed as a potential therapeutic strategy for treating the CNS disorders mentioned. In particular, ligands of G protein-coupled receptors (GPCRs), including metabotropic glutamatergic receptors (mGluRs), have been recognized as promising options for inhibiting excessive Glu transmission. This review discusses the complex interactions of mGlu receptors with their subtypes, including the formation of homo- and heterodimers, which may vary in function and pharmacology depending on their protomer composition. Understanding these intricate details of mGlu receptor structure and function enhances researchers' ability to develop targeted pharmacological interventions, potentially offering new therapeutic avenues for neurological and psychiatric disorders. This review also summarizes the current knowledge of the neuroprotective potential of ligands targeting group III mGluRs in preclinical cellular (in vitro) and animal (in vivo) models of ischemic stroke, TBI, PD, AD, and MS. In recent years, experiments have shown that compounds, especially those activating mGlu4 or mGlu7 receptors, exhibit protective effects in experimental ischemia models. The discovery of allosteric ligands for specific mGluR subtypes has led to reports suggesting that group III mGluRs may be promising targets for neuroprotective therapy in PD (mGlu4R), TBI (mGlu7R), and MS (mGlu8R).
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Affiliation(s)
- Helena Domin
- Maj Institute of Pharmacology, Department of Neurobiology, Polish Academy of Sciences, Smętna 12, Kraków, 31-343, Poland.
| | - Grzegorz Burnat
- Maj Institute of Pharmacology, Department of Neurobiology, Polish Academy of Sciences, Smętna 12, Kraków, 31-343, Poland
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2
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Cristiano N, Cabayé A, Brabet I, Glatthar R, Tora A, Goudet C, Bertrand HO, Goupil-Lamy A, Flor PJ, Pin JP, McCort-Tranchepain I, Acher FC. Novel Inhibitory Site Revealed by XAP044 Mode of Action on the Metabotropic Glutamate 7 Receptor Venus Flytrap Domain. J Med Chem 2024; 67:11662-11687. [PMID: 38691510 DOI: 10.1021/acs.jmedchem.3c01924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2024]
Abstract
Metabotropic glutamate (mGlu) receptors play a key role in modulating most synapses in the brain. The mGlu7 receptors inhibit presynaptic neurotransmitter release and offer therapeutic possibilities for post-traumatic stress disorders or epilepsy. Screening campaigns provided mGlu7-specific allosteric modulators as the inhibitor XAP044 (Gee et al. J. Biol. Chem. 2014). In contrast to other mGlu receptor allosteric modulators, XAP044 does not bind in the transmembrane domain but to the extracellular domain of the mGlu7 receptor and not at the orthosteric site. Here, we identified the mode of action of XAP044, combining synthesis of derivatives, modeling and docking experiments, and mutagenesis. We propose a unique mode of action of these inhibitors, preventing the closure of the Venus flytrap agonist binding domain. While acting as a noncompetitive antagonist of L-AP4, XAP044 and derivatives act as apparent competitive antagonists of LSP4-2022. These data revealed more potent XAP044 analogues and new possibilities to target mGluRs.
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Affiliation(s)
- Nunzia Cristiano
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, Université Paris Cité, CNRS UMR 8601, 75006 Paris, France
| | - Alexandre Cabayé
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, Université Paris Cité, CNRS UMR 8601, 75006 Paris, France
- BIOVIA Dassault Systèmes, F-78140 Vélizy-Villacoublay Cedex, France
| | - Isabelle Brabet
- Institute of Functional Genomics, University of Montpellier, CNRS, Inserm, 34094 Montpellier, France
| | - Ralf Glatthar
- Novartis Biomedical Research, CH-4002 Basel, Switzerland
| | - Amelie Tora
- Institute of Functional Genomics, University of Montpellier, CNRS, Inserm, 34094 Montpellier, France
| | - Cyril Goudet
- Institute of Functional Genomics, University of Montpellier, CNRS, Inserm, 34094 Montpellier, France
| | | | - Anne Goupil-Lamy
- BIOVIA Dassault Systèmes, F-78140 Vélizy-Villacoublay Cedex, France
| | - Peter J Flor
- Laboratory of Molecular and Cellular Neurobiology, Faculty of Biology and Preclinical Medicine, University of Regensburg, 93053 Regensburg, Germany
| | - Jean-Philippe Pin
- Institute of Functional Genomics, University of Montpellier, CNRS, Inserm, 34094 Montpellier, France
| | - Isabelle McCort-Tranchepain
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, Université Paris Cité, CNRS UMR 8601, 75006 Paris, France
| | - Francine C Acher
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, Université Paris Cité, CNRS UMR 8601, 75006 Paris, France
- Saints-Pères Paris Institute for the Neurosciences, Université Paris Cité, CNRS UMR 8003, 75006 Paris, France
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3
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Goda R, Watanabe S, Misaka T. Allosteric modulation of the fish taste receptor type 1 (T1R) family by the extracellular chloride ion. Sci Rep 2023; 13:16348. [PMID: 37770555 PMCID: PMC10539361 DOI: 10.1038/s41598-023-43700-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 09/27/2023] [Indexed: 09/30/2023] Open
Abstract
Many G protein-coupled receptors (GPCRs) are allosterically modulated by inorganic ions. Although the intraoral ionic composition of the oral cavity varies depending on the living environment and feeding behavior, little is known about whether and how it affects the function of taste receptor type 1 (T1R), a member of the class C GPCR family. Here, we report that chloride ions allosterically modulate the functions of specific fish T1Rs, namely, mfT1R2a/mfT1R3 and zfT1R2a/zfT1R3. Site-directed mutagenesis revealed mfT1R2a K265, which lies in the extracellular domain of mfT1R2a, to be as a critical residue for the modulation of mfT1R2a/mfT1R3 by Cl-. However, this residue is not conserved in zfT1R2a, and the introduction of the key residue at the corresponding site of another T1R, mfT1R2b, did not confer Cl- susceptibility. These results indicate the variability of the determinants of Cl- susceptibility.
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Affiliation(s)
- Ryusei Goda
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Soichi Watanabe
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Takumi Misaka
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
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4
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Eslami M, Khazeni S, Khanaghah XM, Asadi MH, Ansari MA, Garjan JH, Lotfalizadeh MH, Bayat M, Taghizadieh M, Taghavi SP, Hamblin MR, Nahand JS. MiRNA-related metastasis in oral cancer: moving and shaking. Cancer Cell Int 2023; 23:182. [PMID: 37635248 PMCID: PMC10463971 DOI: 10.1186/s12935-023-03022-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 08/06/2023] [Indexed: 08/29/2023] Open
Abstract
Across the world, oral cancer is a prevalent tumor. Over the years, both its mortality and incidence have grown. Oral cancer metastasis is a complex process involving cell invasion, migration, proliferation, and egress from cancer tissue either by lymphatic vessels or blood vessels. MicroRNAs (miRNAs) are essential short non-coding RNAs, which can act either as tumor suppressors or as oncogenes to control cancer development. Cancer metastasis is a multi-step process, in which miRNAs can inhibit or stimulate metastasis at all stages, including epithelial-mesenchymal transition, migration, invasion, and colonization, by targeting critical genes in these pathways. On the other hand, long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), two different types of non-coding RNAs, can regulate cancer metastasis by affecting gene expression through cross-talk with miRNAs. We reviewed the scientific literature (Google Scholar, Scopus, and PubMed) for the period 2000-2023 to find reports concerning miRNAs and lncRNA/circRNA-miRNA-mRNA networks, which control the spread of oral cancer cells by affecting invasion, migration, and metastasis. According to these reports, miRNAs are involved in the regulation of metastasis pathways either by directly or indirectly targeting genes associated with metastasis. Moreover, circRNAs and lncRNAs can induce or suppress oral cancer metastasis by acting as competing endogenous RNAs to inhibit the effect of miRNA suppression on specific mRNAs. Overall, non-coding RNAs (especially miRNAs) could help to create innovative therapeutic methods for the control of oral cancer metastases.
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Affiliation(s)
- Meghdad Eslami
- Department of oral and maxillofacial surgery, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Saba Khazeni
- Department of oral and maxillofacial surgery, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Xaniar Mohammadi Khanaghah
- Department of oral and maxillofacial surgery, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Hossein Asadi
- Department of oral and maxillofacial surgery, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohamad Amin Ansari
- Department of oral and maxillofacial surgery, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Javad Hayati Garjan
- Department of oral and maxillofacial surgery, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Mobina Bayat
- Department of Plant, Cell and Molecular Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Taghizadieh
- Department of Pathology, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Seyed Pouya Taghavi
- Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
- Department of Virology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Michael R Hamblin
- Laser Research Centre, Faculty of Health Science, University of Johannesburg, Doornfontein, 2028, South Africa
| | - Javid Sadri Nahand
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
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5
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Pressey JC, de Saint-Rome M, Raveendran VA, Woodin MA. Chloride transporters controlling neuronal excitability. Physiol Rev 2023; 103:1095-1135. [PMID: 36302178 DOI: 10.1152/physrev.00025.2021] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Synaptic inhibition plays a crucial role in regulating neuronal excitability, which is the foundation of nervous system function. This inhibition is largely mediated by the neurotransmitters GABA and glycine that activate Cl--permeable ion channels, which means that the strength of inhibition depends on the Cl- gradient across the membrane. In neurons, the Cl- gradient is primarily mediated by two secondarily active cation-chloride cotransporters (CCCs), NKCC1 and KCC2. CCC-mediated regulation of the neuronal Cl- gradient is critical for healthy brain function, as dysregulation of CCCs has emerged as a key mechanism underlying neurological disorders including epilepsy, neuropathic pain, and autism spectrum disorder. This review begins with an overview of neuronal chloride transporters before explaining the dependent relationship between these CCCs, Cl- regulation, and inhibitory synaptic transmission. We then discuss the evidence for how CCCs can be regulated, including by activity and their protein interactions, which underlie inhibitory synaptic plasticity. For readers who may be interested in conducting experiments on CCCs and neuronal excitability, we have included a section on techniques for estimating and recording intracellular Cl-, including their advantages and limitations. Although the focus of this review is on neurons, we also examine how Cl- is regulated in glial cells, which in turn regulate neuronal excitability through the tight relationship between this nonneuronal cell type and synapses. Finally, we discuss the relatively extensive and growing literature on how CCC-mediated neuronal excitability contributes to neurological disorders.
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Affiliation(s)
- Jessica C Pressey
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Miranda de Saint-Rome
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Vineeth A Raveendran
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Melanie A Woodin
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
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6
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Atsumi N, Yasumatsu K, Takashina Y, Ito C, Yasui N, Margolskee RF, Yamashita A. Chloride ions evoke taste sensations by binding to the extracellular ligand-binding domain of sweet/umami taste receptors. eLife 2023; 12:84291. [PMID: 36852482 PMCID: PMC9977269 DOI: 10.7554/elife.84291] [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: 10/18/2022] [Accepted: 01/31/2023] [Indexed: 03/01/2023] Open
Abstract
Salt taste sensation is multifaceted: NaCl at low or high concentrations is preferably or aversively perceived through distinct pathways. Cl- is thought to participate in taste sensation through an unknown mechanism. Here, we describe Cl- ion binding and the response of taste receptor type 1 (T1r), a receptor family composing sweet/umami receptors. The T1r2a/T1r3 heterodimer from the medaka fish, currently the sole T1r amenable to structural analyses, exhibited a specific Cl- binding in the vicinity of the amino-acid-binding site in the ligand-binding domain (LBD) of T1r3, which is likely conserved across species, including human T1r3. The Cl- binding induced a conformational change in T1r2a/T1r3LBD at sub- to low-mM concentrations, similar to canonical taste substances. Furthermore, oral Cl- application to mice increased impulse frequencies of taste nerves connected to T1r-expressing taste cells and promoted their behavioral preferences attenuated by a T1r-specific blocker or T1r3 knock-out. These results suggest that the Cl- evokes taste sensations by binding to T1r, thereby serving as another preferred salt taste pathway at a low concentration.
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Affiliation(s)
- Nanako Atsumi
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityOkayamaJapan
| | - Keiko Yasumatsu
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityOkayamaJapan
- Tokyo Dental Junior CollegeTokyoJapan
- Monell Chemical Senses CenterPhiladelphiaUnited States
| | - Yuriko Takashina
- School of Pharmaceutical Sciences, Okayama UniversityOkayamaJapan
| | - Chiaki Ito
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityOkayamaJapan
| | - Norihisa Yasui
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityOkayamaJapan
- School of Pharmaceutical Sciences, Okayama UniversityOkayamaJapan
| | | | - Atsuko Yamashita
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityOkayamaJapan
- School of Pharmaceutical Sciences, Okayama UniversityOkayamaJapan
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7
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Gorvin CM. Recent advances in calcium-sensing receptor structures and signaling pathways. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2023; 195:121-135. [PMID: 36707151 DOI: 10.1016/bs.pmbts.2022.06.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The calcium-sensing receptor (CaSR) is a class C GPCR that has a fundamental role in extracellular calcium homeostasis by regulating parathyroid hormone release and urinary calcium excretion. Germline mutations in the receptor cause disorders of calcium homeostasis and studies of the functional effects of these mutations has facilitated understanding of CaSR signaling and how allosteric modulators affect these responses. In the past year, five cryo-EM structures of the near full-length CaSR have been published, demonstrating how agonist-binding transmits changes in the CaSR extracellular domain to the transmembrane region to activate G proteins, and how allosteric modulators affect these structural dynamics. Additionally, several recent studies have identified CaSR interacting proteins that regulate CaSR signaling and trafficking and contribute to understanding how the receptor achieves rapid and diverse physiological responses.
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Affiliation(s)
- Caroline M Gorvin
- Centre of Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, Birmingham, United Kingdom; Institute of Metabolism and Systems Research (IMSR) and Centre for Endocrinology, Diabetes and Metabolism, Birmingham Health Partners, University of Birmingham, Birmingham, United Kingdom.
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8
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Boahen F, Doyon N, Deteix J. Sensitivity of the electrical response of a node of Ranvier model to alterations of the myelin sheath geometry. J Math Biol 2022; 86:17. [PMID: 36534161 DOI: 10.1007/s00285-022-01841-0] [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: 04/12/2021] [Revised: 08/31/2022] [Accepted: 11/21/2022] [Indexed: 12/23/2022]
Abstract
Nodes of Ranvier play critical roles in the generation and transmission of action potentials. Alterations in node properties during pathology and/or development are known to affect the speed and quality of electrical transmission. From a modelling standpoint, nodes of Ranvier are often described by systems of ordinary differential equations neglecting or greatly simplifying their geometric structure. These approaches fail to accurately describe how fine scale alteration in the node geometry or in myelin thickness in the paranode region will impact action potential generation and transmission. Here, we rely on a finite element approximation to describe the three dimensional geometry of a node of Ranvier. With this, we are able to investigate how sensitive is the electrical response to alterations in the myelin sheath and paranode geometry. We could in particular investigate irregular loss of myelin, which might be more physiologically relevant than the uniform loss often described through simpler modelling approaches.
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Affiliation(s)
- Frank Boahen
- Groupe Interdisciplinaire de Recherche en Éléments Finis (GIREF), Département de mathématiques et statistique, Université Laval Pavillon Vachon, 1045 Avenue de la médecine, Université Laval, Québec, QC, Canada
| | - Nicolas Doyon
- Groupe Interdisciplinaire de Recherche en Éléments Finis (GIREF), Département de mathématiques et statistique, Université Laval Pavillon Vachon, 1045 Avenue de la médecine, Université Laval, Québec, QC, Canada.
| | - Jean Deteix
- Groupe Interdisciplinaire de Recherche en Éléments Finis (GIREF), Département de mathématiques et statistique, Université Laval Pavillon Vachon, 1045 Avenue de la médecine, Université Laval, Québec, QC, Canada
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9
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Derieux C, Léauté A, Brugoux A, Jaccaz D, Terrier C, Pin JP, Kniazeff J, Le Merrer J, Becker JAJ. Chronic sodium bromide treatment relieves autistic-like behavioral deficits in three mouse models of autism. Neuropsychopharmacology 2022; 47:1680-1692. [PMID: 35418620 PMCID: PMC9283539 DOI: 10.1038/s41386-022-01317-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 03/07/2022] [Accepted: 03/21/2022] [Indexed: 12/15/2022]
Abstract
Autism Spectrum Disorders (ASD) are neurodevelopmental disorders whose diagnosis relies on deficient social interaction and communication together with repetitive behavior. To date, no pharmacological treatment has been approved that ameliorates social behavior in patients with ASD. Based on the excitation/inhibition imbalance theory of autism, we hypothesized that bromide ions, long used as an antiepileptic medication, could relieve core symptoms of ASD. We evaluated the effects of chronic sodium bromide (NaBr) administration on autistic-like symptoms in three genetic mouse models of autism: Oprm1-/-, Fmr1-/- and Shank3Δex13-16-/- mice. We showed that chronic NaBr treatment relieved autistic-like behaviors in these three models. In Oprm1-/- mice, these beneficial effects were superior to those of chronic bumetanide administration. At transcriptional level, chronic NaBr in Oprm1 null mice was associated with increased expression of genes coding for chloride ions transporters, GABAA receptor subunits, oxytocin and mGlu4 receptor. Lastly, we uncovered synergistic alleviating effects of chronic NaBr and a positive allosteric modulator (PAM) of mGlu4 receptor on autistic-like behavior in Oprm1-/- mice. We evidenced in heterologous cells that bromide ions behave as PAMs of mGlu4, providing a molecular mechanism for such synergy. Our data reveal the therapeutic potential of bromide ions, alone or in combination with a PAM of mGlu4 receptor, for the treatment of ASDs.
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Affiliation(s)
- Cécile Derieux
- grid.464126.30000 0004 0385 4036Physiologie de la Reproduction et des Comportements, INRAE UMR0085, CNRS UMR7247, IFCE, Université de Tours, Inserm, 37380 Nouzilly, France ,grid.12366.300000 0001 2182 6141UMR1253, iBrain, Université de Tours, Inserm, CNRS, Faculté des Sciences et Techniques, Parc de Grandmont, 37200 Tours, France ,grid.121334.60000 0001 2097 0141Institut de Génomique Fonctionnelle (IGF), Université de Montpellier, CNRS, Inserm, 34094 Montpellier, France
| | - Audrey Léauté
- grid.464126.30000 0004 0385 4036Physiologie de la Reproduction et des Comportements, INRAE UMR0085, CNRS UMR7247, IFCE, Université de Tours, Inserm, 37380 Nouzilly, France
| | - Agathe Brugoux
- grid.464126.30000 0004 0385 4036Physiologie de la Reproduction et des Comportements, INRAE UMR0085, CNRS UMR7247, IFCE, Université de Tours, Inserm, 37380 Nouzilly, France ,grid.12366.300000 0001 2182 6141UMR1253, iBrain, Université de Tours, Inserm, CNRS, Faculté des Sciences et Techniques, Parc de Grandmont, 37200 Tours, France
| | - Déborah Jaccaz
- Unité Expérimentale de Physiologie Animale de l’Orfrasière, INRAE UE0028, 37380 Nouzilly, France
| | - Claire Terrier
- grid.464126.30000 0004 0385 4036Physiologie de la Reproduction et des Comportements, INRAE UMR0085, CNRS UMR7247, IFCE, Université de Tours, Inserm, 37380 Nouzilly, France ,grid.12366.300000 0001 2182 6141UMR1253, iBrain, Université de Tours, Inserm, CNRS, Faculté des Sciences et Techniques, Parc de Grandmont, 37200 Tours, France
| | - Jean-Philippe Pin
- grid.121334.60000 0001 2097 0141Institut de Génomique Fonctionnelle (IGF), Université de Montpellier, CNRS, Inserm, 34094 Montpellier, France
| | - Julie Kniazeff
- grid.121334.60000 0001 2097 0141Institut de Génomique Fonctionnelle (IGF), Université de Montpellier, CNRS, Inserm, 34094 Montpellier, France
| | - Julie Le Merrer
- Physiologie de la Reproduction et des Comportements, INRAE UMR0085, CNRS UMR7247, IFCE, Université de Tours, Inserm, 37380, Nouzilly, France. .,UMR1253, iBrain, Université de Tours, Inserm, CNRS, Faculté des Sciences et Techniques, Parc de Grandmont, 37200, Tours, France.
| | - Jerome A. J. Becker
- grid.464126.30000 0004 0385 4036Physiologie de la Reproduction et des Comportements, INRAE UMR0085, CNRS UMR7247, IFCE, Université de Tours, Inserm, 37380 Nouzilly, France ,grid.12366.300000 0001 2182 6141UMR1253, iBrain, Université de Tours, Inserm, CNRS, Faculté des Sciences et Techniques, Parc de Grandmont, 37200 Tours, France
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10
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Acher FC, Cabayé A, Eshak F, Goupil-Lamy A, Pin JP. Metabotropic glutamate receptor orthosteric ligands and their binding sites. Neuropharmacology 2022; 204:108886. [PMID: 34813860 DOI: 10.1016/j.neuropharm.2021.108886] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 11/13/2021] [Accepted: 11/15/2021] [Indexed: 12/21/2022]
Abstract
Metabotropic glutamate receptors (mGluRs) have been discovered almost four decades ago. Since then, their pharmacology has been largely developed as well as their structural organization. Indeed mGluRs are attractive therapeutic targets for numerous psychiatric and neurological disorders because of their modulating role of synaptic transmission. The more recent drug discovery programs have mostly concentrated on allosteric modulators. However, orthosteric agonists and antagonists have remained unavoidable pharmacological tools as, although not expected, many of them can reach the brain, or can be modified to reach the brain. This review focuses on the most common orthosteric ligands as well as on the few allosteric modulators interacting with the glutamate binding domain. The 3D-structures of these ligands at their binding sites are reported. For most of them, X-Ray structures or docked homology models are available. Because of the high conservation of the binding site, subtype selective agonists were not easy to find. Yet, some were discovered when extending their chemical structures in order to reach selective sites of the receptors.
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Affiliation(s)
- Francine C Acher
- Faculty of Basic and Biomedical Sciences, University of Paris, CNRS, 75270 Paris Cedex 06, France.
| | - Alexandre Cabayé
- Faculty of Basic and Biomedical Sciences, University of Paris, CNRS, 75270 Paris Cedex 06, France; BIOVIA, Dassault Systèmes, F-78140 Vélizy-Villacoublay Cedex, France
| | - Floriane Eshak
- Faculty of Basic and Biomedical Sciences, University of Paris, CNRS, 75270 Paris Cedex 06, France
| | - Anne Goupil-Lamy
- BIOVIA, Dassault Systèmes, F-78140 Vélizy-Villacoublay Cedex, France
| | - Jean-Philippe Pin
- Institut de Génomique Fonctionnelle, University of Montpellier, CNRS, INSERM, 34094 Montpellier Cedex 5, France
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11
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Ye. M. Makogonenko RYM, Hrabovskyi OO, Bereznytskyj GK, Pyrogova LV, Gogolinskaya GK, Makogonenko YM. Chlorine-binding structures: role and organization in different proteins. UKRAINIAN BIOCHEMICAL JOURNAL 2021. [DOI: 10.15407/ubj93.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The review focuses on chloride-binding structures in the proteins of bacteria, plants, viruses and animals. The structure and amino acid composition of the chloride-binding site and its role in the functioning of structural, regulatory, transport, receptor, channel proteins, transcription factors and enzymes are considered. Data on the important role of chloride-binding structures and chloride anions in the polymerization of fibrin are presented.
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12
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Gregory KJ, Goudet C. International Union of Basic and Clinical Pharmacology. CXI. Pharmacology, Signaling, and Physiology of Metabotropic Glutamate Receptors. Pharmacol Rev 2020; 73:521-569. [PMID: 33361406 DOI: 10.1124/pr.119.019133] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Metabotropic glutamate (mGlu) receptors respond to glutamate, the major excitatory neurotransmitter in the mammalian brain, mediating a modulatory role that is critical for higher-order brain functions such as learning and memory. Since the first mGlu receptor was cloned in 1992, eight subtypes have been identified along with many isoforms and splice variants. The mGlu receptors are transmembrane-spanning proteins belonging to the class C G protein-coupled receptor family and represent attractive targets for a multitude of central nervous system disorders. Concerted drug discovery efforts over the past three decades have yielded a wealth of pharmacological tools including subtype-selective agents that competitively block or mimic the actions of glutamate or act allosterically via distinct sites to enhance or inhibit receptor activity. Herein, we review the physiologic and pathophysiological roles for individual mGlu receptor subtypes including the pleiotropic nature of intracellular signal transduction arising from each. We provide a comprehensive analysis of the in vitro and in vivo pharmacological properties of prototypical and commercially available orthosteric agonists and antagonists as well as allosteric modulators, including ligands that have entered clinical trials. Finally, we highlight emerging areas of research that hold promise to facilitate rational design of highly selective mGlu receptor-targeting therapeutics in the future. SIGNIFICANCE STATEMENT: The metabotropic glutamate receptors are attractive therapeutic targets for a range of psychiatric and neurological disorders. Over the past three decades, intense discovery efforts have yielded diverse pharmacological tools acting either competitively or allosterically, which have enabled dissection of fundamental biological process modulated by metabotropic glutamate receptors and established proof of concept for many therapeutic indications. We review metabotropic glutamate receptor molecular pharmacology and highlight emerging areas that are offering new avenues to selectively modulate neurotransmission.
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Affiliation(s)
- Karen J Gregory
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia (K.J.G.) and Institut de Génomique Fonctionnelle (IGF), University of Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de la Sante et de la Recherche Medicale (INSERM), Montpellier, France (C.G.)
| | - Cyril Goudet
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia (K.J.G.) and Institut de Génomique Fonctionnelle (IGF), University of Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de la Sante et de la Recherche Medicale (INSERM), Montpellier, France (C.G.)
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13
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Ellaithy A, Gonzalez-Maeso J, Logothetis DA, Levitz J. Structural and Biophysical Mechanisms of Class C G Protein-Coupled Receptor Function. Trends Biochem Sci 2020; 45:1049-1064. [PMID: 32861513 PMCID: PMC7642020 DOI: 10.1016/j.tibs.2020.07.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 07/22/2020] [Accepted: 07/30/2020] [Indexed: 02/07/2023]
Abstract
Groundbreaking structural and spectroscopic studies of class A G protein-coupled receptors (GPCRs), such as rhodopsin and the β2 adrenergic receptor, have provided a picture of how structural rearrangements between transmembrane helices control ligand binding, receptor activation, and effector coupling. However, the activation mechanism of other GPCR classes remains more elusive, in large part due to complexity in their domain assembly and quaternary structure. In this review, we focus on the class C GPCRs, which include metabotropic glutamate receptors (mGluRs) and gamma-aminobutyric acid B (GABAB) receptors (GABABRs) most prominently. We discuss the unique biophysical questions raised by the presence of large extracellular ligand-binding domains (LBDs) and constitutive homo/heterodimerization. Furthermore, we discuss how recent studies have begun to unravel how these fundamental class C GPCR features impact the processes of ligand binding, receptor activation, signal transduction, regulation by accessory proteins, and crosstalk with other GPCRs.
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Affiliation(s)
- Amr Ellaithy
- Department of Neurology, University of Iowa, Iowa City, IA 52242, USA; Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA; Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Javier Gonzalez-Maeso
- Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA
| | - Diomedes A Logothetis
- Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, MA 02115, USA; Department of Chemistry and Chemical Biology, College of Science and Center for Drug Discovery, Northeastern University, Boston, MA 02115, USA
| | - Joshua Levitz
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10065, USA.
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14
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Illuminating the allosteric modulation of the calcium-sensing receptor. Proc Natl Acad Sci U S A 2020; 117:21711-21722. [PMID: 32817431 DOI: 10.1073/pnas.1922231117] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Many membrane receptors are regulated by nutrients. However, how these nutrients control a single receptor remains unknown, even in the case of the well-studied calcium-sensing receptor CaSR, which is regulated by multiple factors, including ions and amino acids. Here, we developed an innovative cell-free Förster resonance energy transfer (FRET)-based conformational CaSR biosensor to clarify the main conformational changes associated with activation. By allowing a perfect control of ambient nutrients, this assay revealed that Ca2+ alone fully stabilizes the active conformation, while amino acids behave as pure positive allosteric modulators. Based on the identification of Ca2+ activation sites, we propose a molecular basis for how these different ligands cooperate to control CaSR activation. Our results provide important information on CaSR function and improve our understanding of the effects of genetic mutations responsible for human diseases. They also provide insights into how a receptor can integrate signals from various nutrients to better adapt to the cell response.
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15
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Abstract
Cl- is the major extracellular (Cl-out) and intracellular (Cl-in) anion whose concentration is actively regulated by multiple transporters. These transporters generate Cl- gradients across the plasma membrane and between the cytoplasm and intracellular organelles. [Cl-]in changes rapidly in response to cell stimulation and influences many physiological functions, as well as cellular and systemic homeostasis. However, less appreciated is the signaling function of Cl-. Cl- interacts with multiple proteins to directly modify their activity. This review highlights the signaling function of Cl- and argues that Cl- is a bona fide signaling ion, a function deserving extensive exploration.
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Affiliation(s)
- Benjamin P Lüscher
- Epithelial Signaling and Transport Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland
| | - Laura Vachel
- Epithelial Signaling and Transport Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland
| | - Ehud Ohana
- Department of Clinical Biochemistry and Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Shmuel Muallem
- Epithelial Signaling and Transport Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland
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16
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Girard B, Tuduri P, Moreno MP, Sakkaki S, Barboux C, Bouschet T, Varrault A, Vitre J, McCort-Tranchepain I, Dairou J, Acher F, Fagni L, Marchi N, Perroy J, Bertaso F. The mGlu7 receptor provides protective effects against epileptogenesis and epileptic seizures. Neurobiol Dis 2019; 129:13-28. [PMID: 31051234 DOI: 10.1016/j.nbd.2019.04.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 03/28/2019] [Accepted: 04/29/2019] [Indexed: 01/26/2023] Open
Abstract
Finding new targets to control or reduce seizure activity is essential to improve the management of epileptic patients. We hypothesized that activation of the pre-synaptic and inhibitory metabotropic glutamate receptor type 7 (mGlu7) reduces spontaneous seizures. We tested LSP2-9166, a recently developed mGlu7/4 agonist with unprecedented potency on mGlu7 receptors, in two paradigms of epileptogenesis. In a model of chemically induced epileptogenesis (pentylenetetrazole systemic injection), LSP2-9166 induces an anti-epileptogenic effect rarely observed in preclinical studies. In particular, we found a bidirectional modulation of seizure progression by mGlu4 and mGlu7 receptors, the latter preventing kindling. In the intra-hippocampal injection of kainic acid mouse model that mimics the human mesial temporal lobe epilepsy, we found that LSP2-9166 reduces seizure frequency and hippocampal sclerosis. LSP2-9166 also acts as an anti-seizure drug on established seizures in both models tested. Specific modulation of the mGlu7 receptor could represent a novel approach to reduce pathological network remodeling.
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Affiliation(s)
- Benoit Girard
- IGF, CNRS, INSERM, Univ Montpellier, Montpellier, France
| | - Pola Tuduri
- IGF, CNRS, INSERM, Univ Montpellier, Montpellier, France
| | | | - Sophie Sakkaki
- IGF, CNRS, INSERM, Univ Montpellier, Montpellier, France
| | | | | | - Annie Varrault
- IGF, CNRS, INSERM, Univ Montpellier, Montpellier, France
| | - Jihane Vitre
- IGF, CNRS, INSERM, Univ Montpellier, Montpellier, France
| | | | | | | | - Laurent Fagni
- IGF, CNRS, INSERM, Univ Montpellier, Montpellier, France
| | - Nicola Marchi
- IGF, CNRS, INSERM, Univ Montpellier, Montpellier, France
| | - Julie Perroy
- IGF, CNRS, INSERM, Univ Montpellier, Montpellier, France
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17
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Yanagawa M, Hiroshima M, Togashi Y, Abe M, Yamashita T, Shichida Y, Murata M, Ueda M, Sako Y. Single-molecule diffusion-based estimation of ligand effects on G protein-coupled receptors. Sci Signal 2018; 11:11/548/eaao1917. [PMID: 30228224 DOI: 10.1126/scisignal.aao1917] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
G protein-coupled receptors (GPCRs) are major drug targets. Developing a method to measure the activities of GPCRs is essential for pharmacology and drug screening. However, it is difficult to measure the effects of a drug by monitoring the receptor on the cell surface; thus, changes in the concentrations of downstream signaling molecules, which depend on the signaling pathway selectivity of the receptor, are often used as an index of receptor activity. We show that single-molecule imaging analysis provides an alternative method for assessing the effects of ligands on GPCRs. Using total internal reflection fluorescence microscopy (TIRFM), we monitored the dynamics of the diffusion of metabotropic glutamate receptor 3 (mGluR3), a class C GPCR, under various ligand conditions. Our single-molecule tracking analysis demonstrated that increases and decreases in the average diffusion coefficient of mGluR3 quantitatively reflected the ligand-dependent inactivation and activation of receptors, respectively. Through experiments with inhibitors and dual-color single-molecule imaging analysis, we found that the diffusion of receptor molecules was altered by common physiological events associated with GPCRs, including G protein binding, and receptor accumulation in clathrin-coated pits. We also confirmed that agonist also decreased the average diffusion coefficient for class A and B GPCRs, demonstrating that this parameter is a good index for estimating ligand effects on many GPCRs regardless of their phylogenetic groups, the chemical properties of the ligands, or G protein-coupling selectivity.
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Affiliation(s)
- Masataka Yanagawa
- Cellular Informatics Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Michio Hiroshima
- Cellular Informatics Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.,Laboratory for Cell Signaling Dynamics, RIKEN Center for Biosystems Dynamics Research, 6-2-3, Furuedai, Suita, Osaka 565-0874, Japan.,Japan Science and Technology Agency (JST), Core Research for Evolutional Science and Technology (CREST), Saitama, Japan
| | - Yuichi Togashi
- Laboratory for Cell Signaling Dynamics, RIKEN Center for Biosystems Dynamics Research, 6-2-3, Furuedai, Suita, Osaka 565-0874, Japan.,Research Center for the Mathematics on Chromatin Live Dynamics, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan.,Cybermedia Center, Osaka University, 5-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
| | - Mitsuhiro Abe
- Cellular Informatics Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Takahiro Yamashita
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Yoshinori Shichida
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.,Research Organization for Science and Technology, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan
| | - Masayuki Murata
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Komaba 3-8-1, Meguro-ku, Tokyo 153-8902, Japan
| | - Masahiro Ueda
- Laboratory for Cell Signaling Dynamics, RIKEN Center for Biosystems Dynamics Research, 6-2-3, Furuedai, Suita, Osaka 565-0874, Japan.,Laboratory of Single Molecule Biology, Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yasushi Sako
- Cellular Informatics Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
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18
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Gates C, Backos DS, Reigan P, Kang HJ, Koerner C, Mirzaei J, Natale NR. Isoxazolo[3,4-d]pyridazinones positively modulate the metabotropic glutamate subtypes 2 and 4. Bioorg Med Chem 2018; 26:4797-4803. [PMID: 30143366 PMCID: PMC6675577 DOI: 10.1016/j.bmc.2018.08.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 08/01/2018] [Accepted: 08/09/2018] [Indexed: 11/29/2022]
Abstract
Isoxazolo[3,4-d] pyridazinones ([3,4-d]s) are selective positive modulators of the metabotropic glutamate receptors (mGluRs) subtypes 2 and 4, with no functional cross reactivity at mGluR1a, mGLuR5 or mGluR8. Modest binding for two of the [3,4-d]s is observed at the allosteric fenobam mGluR5 site, but not sufficient to translate into a functional effect. The structure activity relationship (SAR) for mGluR2 and mGluR4 are distinct: the compounds which select for mGluR2 all contain fluorine on the N-6 aryl group. Furthermore, the [3,4-d]s in this study showed no significant binding at inhibitory GABAA, nor excitatory NMDA receptors, and previously we had disclosed that they lack significant activity at the System Xc-Antiporter. A homology model based on Conn's mGluR1 crystal structure was examined, and suggested explanations for a preference for allosteric over orthosteric binding, subtype selectivity, and suggested avenues for optimization of efficacy as a reasonable working hypothesis.
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Affiliation(s)
- Christina Gates
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT 59812, United States
| | - Donald S Backos
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Anschutz Medical Campus, University of Colorado Denver, Aurora, CO 80045, United States
| | - Philip Reigan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Anschutz Medical Campus, University of Colorado Denver, Aurora, CO 80045, United States
| | - Hye Jin Kang
- Psychoactive Drug Screening Program, University of North Carolina at Chapel Hill, Department of Pharmacology, School of Medicine, 2113 Genetics Medicine Building, 120 Mason Farm Road, Chapel Hill, NC 27599, United States
| | - Chris Koerner
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT 59812, United States
| | - Joseph Mirzaei
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT 59812, United States
| | - N R Natale
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT 59812, United States; Skaggs School of Pharmacy and Pharmaceutical Sciences, Anschutz Medical Campus, University of Colorado Denver, Aurora, CO 80045, United States.
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19
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Sensitivity analysis of the Poisson Nernst-Planck equations: a finite element approximation for the sensitive analysis of an electrodiffusion model. J Math Biol 2018; 78:21-56. [PMID: 30187223 DOI: 10.1007/s00285-018-1266-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 04/07/2018] [Indexed: 11/27/2022]
Abstract
Biological structures exhibiting electric potential fluctuations such as neuron and neural structures with complex geometries are modelled using an electrodiffusion or Poisson Nernst-Planck system of equations. These structures typically depend upon several parameters displaying a large degree of variation or that cannot be precisely inferred experimentally. It is crucial to understand how the mathematical model (and resulting simulations) depend on specific values of these parameters. Here we develop a rigorous approach based on the sensitivity equation for the electrodiffusion model. To illustrate the proposed methodology, we investigate the sensitivity of the electrical response of a node of Ranvier with respect to ionic diffusion coefficients and the membrane dielectric permittivity.
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20
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Tora AS, Rovira X, Cao AM, Cabayé A, Olofsson L, Malhaire F, Scholler P, Baik H, Van Eeckhaut A, Smolders I, Rondard P, Margeat E, Acher F, Pin JP, Goudet C. Chloride ions stabilize the glutamate-induced active state of the metabotropic glutamate receptor 3. Neuropharmacology 2018; 140:275-286. [PMID: 30102917 DOI: 10.1016/j.neuropharm.2018.08.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 07/25/2018] [Accepted: 08/09/2018] [Indexed: 02/06/2023]
Abstract
Due to the essential roles of glutamate, detection and response to a large range of extracellular concentrations of this excitatory amino acid are necessary for the fine-tuning of brain functions. Metabotropic glutamate receptors (mGluRs) are implicated in shaping the activity of many synapses in the central nervous system. Among the eight mGluR subtypes, there is increasing interest in studying the mGlu3 receptor which has recently been linked to various diseases, including psychiatric disorders. This receptor displays striking functional properties, with a high and, often, full basal activity, making its study elusive in heterologous systems. Here, we demonstrate that Cl- ions exert strong positive allosteric modulation of glutamate on the mGlu3 receptor. We have also identified the molecular and structural determinants lying behind this allostery: a unique interactive "chloride-lock" network. Indeed, Cl- ions dramatically stabilize the glutamate-induced active state of the extracellular domain of the mGlu3 receptor. Thus, the mGlu3 receptors' large basal activity does not correspond to a constitutive activity in absence of agonist. Instead, it results mostly from a Cl-mediated amplified response to low ambient glutamate concentrations, such as those measured in cell media. This strong interaction between glutamate and Cl- ions allows the mGlu3 receptor to sense and efficiently react to sub-micromolar concentrations of glutamate, making it the most sensitive member of mGluR family.
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Affiliation(s)
- Amélie S Tora
- IGF, CNRS, INSERM, Univ. de Montpellier, Montpellier, F-34094, Montpellier, France
| | - Xavier Rovira
- IGF, CNRS, INSERM, Univ. de Montpellier, Montpellier, F-34094, Montpellier, France; Present Address: Molecular Photopharmacology Research Group, The Tissue Repair and Regeneration Laboratory, University of Vic - Central University of Catalonia, C. de La Laura,13, 08500, Vic, Spain
| | - Anne-Marinette Cao
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, F-34094, Montpellier, France
| | - Alexandre Cabayé
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, CNRS UMR8601, Université Paris Descartes, Sorbonne Paris Cité, F-75270, Paris Cedex 6, France
| | - Linnéa Olofsson
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, F-34094, Montpellier, France
| | - Fanny Malhaire
- IGF, CNRS, INSERM, Univ. de Montpellier, Montpellier, F-34094, Montpellier, France
| | - Pauline Scholler
- IGF, CNRS, INSERM, Univ. de Montpellier, Montpellier, F-34094, Montpellier, France
| | - Hayeon Baik
- IGF, CNRS, INSERM, Univ. de Montpellier, Montpellier, F-34094, Montpellier, France
| | - Ann Van Eeckhaut
- Research Group Experimental Pharmacology (EFAR/FASC), Center for Neurosciences (C4N), Vrije Universiteit Brussel (VUB), 1090, Brussel, Belgium
| | - Ilse Smolders
- Research Group Experimental Pharmacology (EFAR/FASC), Center for Neurosciences (C4N), Vrije Universiteit Brussel (VUB), 1090, Brussel, Belgium
| | - Philippe Rondard
- IGF, CNRS, INSERM, Univ. de Montpellier, Montpellier, F-34094, Montpellier, France
| | - Emmanuel Margeat
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, F-34094, Montpellier, France
| | - Francine Acher
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, CNRS UMR8601, Université Paris Descartes, Sorbonne Paris Cité, F-75270, Paris Cedex 6, France.
| | - Jean-Philippe Pin
- IGF, CNRS, INSERM, Univ. de Montpellier, Montpellier, F-34094, Montpellier, France.
| | - Cyril Goudet
- IGF, CNRS, INSERM, Univ. de Montpellier, Montpellier, F-34094, Montpellier, France.
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21
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Selvam C, Lemasson IA, Brabet I, Oueslati N, Karaman B, Cabaye A, Tora AS, Commare B, Courtiol T, Cesarini S, McCort-Tranchepain I, Rigault D, Mony L, Bessiron T, McLean H, Leroux FR, Colobert F, Daniel H, Goupil-Lamy A, Bertrand HO, Goudet C, Pin JP, Acher FC. Increased Potency and Selectivity for Group III Metabotropic Glutamate Receptor Agonists Binding at Dual sites. J Med Chem 2018; 61:1969-1989. [DOI: 10.1021/acs.jmedchem.7b01438] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Chelliah Selvam
- Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France
| | - Isabelle A. Lemasson
- Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France
| | - Isabelle Brabet
- IGF, CNRS, INSERM, Université Montpellier, F-34094 Montpellier, France
| | - Nadia Oueslati
- IGF, CNRS, INSERM, Université Montpellier, F-34094 Montpellier, France
| | - Berin Karaman
- Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France
| | - Alexandre Cabaye
- Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France
| | - Amélie S. Tora
- IGF, CNRS, INSERM, Université Montpellier, F-34094 Montpellier, France
| | - Bruno Commare
- Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France
- UMR 7509/CNRS/ECPM, Université de Strasbourg, 25 Rue Becquerel, 67087 Strasbourg 02, France
| | - Tiphanie Courtiol
- Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France
| | - Sara Cesarini
- Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France
| | - Isabelle McCort-Tranchepain
- Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France
| | - Delphine Rigault
- Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France
| | - Laetitia Mony
- Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France
- Institut de Biologie, Ecole Normale Supérieure, CNRS UMR 8197, INSERM U1024, PSL University, 46 rue d’Ulm, 75005 Paris, France
| | - Thomas Bessiron
- Pharmacologie et Biochimie de la Synapse, Université Paris-Sud/CNRS/NeuroPSI−UMR 9197, F-91405 Orsay, France
| | - Heather McLean
- Pharmacologie et Biochimie de la Synapse, Université Paris-Sud/CNRS/NeuroPSI−UMR 9197, F-91405 Orsay, France
| | - Frédéric R. Leroux
- UMR 7509/CNRS/ECPM, Université de Strasbourg, 25 Rue Becquerel, 67087 Strasbourg 02, France
| | - Françoise Colobert
- UMR 7509/CNRS/ECPM, Université de Strasbourg, 25 Rue Becquerel, 67087 Strasbourg 02, France
| | - Hervé Daniel
- Pharmacologie et Biochimie de la Synapse, Université Paris-Sud/CNRS/NeuroPSI−UMR 9197, F-91405 Orsay, France
| | - Anne Goupil-Lamy
- BIOVIA, Dassault Systèmes, 10 rue Marcel Dassault, CS 40501, 78946 Vélizy-Villacoublay Cedex, France
| | - Hugues-Olivier Bertrand
- BIOVIA, Dassault Systèmes, 10 rue Marcel Dassault, CS 40501, 78946 Vélizy-Villacoublay Cedex, France
| | - Cyril Goudet
- IGF, CNRS, INSERM, Université Montpellier, F-34094 Montpellier, France
| | - Jean-Philippe Pin
- IGF, CNRS, INSERM, Université Montpellier, F-34094 Montpellier, France
| | - Francine C. Acher
- Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France
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Goudet C, Rovira X, Llebaria A. Shedding light on metabotropic glutamate receptors using optogenetics and photopharmacology. Curr Opin Pharmacol 2018; 38:8-15. [DOI: 10.1016/j.coph.2018.01.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 01/30/2018] [Indexed: 11/27/2022]
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23
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Charvin D, Pomel V, Ortiz M, Frauli M, Scheffler S, Steinberg E, Baron L, Deshons L, Rudigier R, Thiarc D, Morice C, Manteau B, Mayer S, Graham D, Giethlen B, Brugger N, Hédou G, Conquet F, Schann S. Discovery, Structure–Activity Relationship, and Antiparkinsonian Effect of a Potent and Brain-Penetrant Chemical Series of Positive Allosteric Modulators of Metabotropic Glutamate Receptor 4. J Med Chem 2017; 60:8515-8537. [DOI: 10.1021/acs.jmedchem.7b00991] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Delphine Charvin
- Prexton Therapeutics, 14 Chemin
des Aulx, 1228 Plan-les-Ouates, Geneva, Switzerland
| | - Vincent Pomel
- Prexton Therapeutics, 14 Chemin
des Aulx, 1228 Plan-les-Ouates, Geneva, Switzerland
| | - Millan Ortiz
- Prexton Therapeutics, 14 Chemin
des Aulx, 1228 Plan-les-Ouates, Geneva, Switzerland
| | - Mélanie Frauli
- Domain Therapeutics, 850 Boulevard Sébastien Brant, 67400 Illkirch-Strasbourg, France
| | - Sophie Scheffler
- Domain Therapeutics, 850 Boulevard Sébastien Brant, 67400 Illkirch-Strasbourg, France
| | - Edith Steinberg
- Domain Therapeutics, 850 Boulevard Sébastien Brant, 67400 Illkirch-Strasbourg, France
| | - Luc Baron
- Domain Therapeutics, 850 Boulevard Sébastien Brant, 67400 Illkirch-Strasbourg, France
| | - Laurène Deshons
- Domain Therapeutics, 850 Boulevard Sébastien Brant, 67400 Illkirch-Strasbourg, France
| | - Rachel Rudigier
- Prestwick Chemical, 220 Boulevard Gonthier d’Andernach, 67400 Illkirch-Strasbourg, France
| | - Delphine Thiarc
- Prestwick Chemical, 220 Boulevard Gonthier d’Andernach, 67400 Illkirch-Strasbourg, France
| | - Christophe Morice
- Prestwick Chemical, 220 Boulevard Gonthier d’Andernach, 67400 Illkirch-Strasbourg, France
| | - Baptiste Manteau
- Domain Therapeutics, 850 Boulevard Sébastien Brant, 67400 Illkirch-Strasbourg, France
| | - Stanislas Mayer
- Domain Therapeutics, 850 Boulevard Sébastien Brant, 67400 Illkirch-Strasbourg, France
| | - Danielle Graham
- EMD Serono, 45A Middlesex Turnpike, Billerica, Massachusetts 0182, United States
| | - Bruno Giethlen
- Prestwick Chemical, 220 Boulevard Gonthier d’Andernach, 67400 Illkirch-Strasbourg, France
| | - Nadia Brugger
- EMD Serono, 45A Middlesex Turnpike, Billerica, Massachusetts 0182, United States
| | - Gaël Hédou
- EMD Serono, 45A Middlesex Turnpike, Billerica, Massachusetts 0182, United States
| | - François Conquet
- Prexton Therapeutics, 14 Chemin
des Aulx, 1228 Plan-les-Ouates, Geneva, Switzerland
| | - Stephan Schann
- Domain Therapeutics, 850 Boulevard Sébastien Brant, 67400 Illkirch-Strasbourg, France
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24
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Dalton JAR, Pin JP, Giraldo J. Analysis of positive and negative allosteric modulation in metabotropic glutamate receptors 4 and 5 with a dual ligand. Sci Rep 2017; 7:4944. [PMID: 28694498 PMCID: PMC5504000 DOI: 10.1038/s41598-017-05095-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 05/25/2017] [Indexed: 12/24/2022] Open
Abstract
As class C GPCRs and regulators of synaptic activity, human metabotropic glutamate receptors (mGluRs) 4 and 5 are prime targets for allosteric modulation, with mGlu5 inhibition or mGlu4 stimulation potentially treating conditions like chronic pain and Parkinson’s disease. As an allosteric modulator that can bind both receptors, 2-Methyl-6-(phenylethynyl)pyridine (MPEP) is able to negatively modulate mGlu5 or positively modulate mGlu4. At a structural level, how it elicits these responses and how mGluRs undergo activation is unclear. Here, we employ homology modelling and 30 µs of atomistic molecular dynamics (MD) simulations to probe allosteric conformational change in mGlu4 and mGlu5, with and without docked MPEP. Our results identify several structural differences between mGlu4 and mGlu5, as well as key differences responsible for MPEP-mediated positive and negative allosteric modulation, respectively. A novel mechanism of mGlu4 activation is revealed, which may apply to all mGluRs in general. This involves conformational changes in TM3, TM4 and TM5, separation of intracellular loop 2 (ICL2) from ICL1/ICL3, and destabilization of the ionic-lock. On the other hand, mGlu5 experiences little disturbance when MPEP binds, maintaining its inactive state with reduced conformational fluctuation. In addition, when MPEP is absent, a lipid molecule can enter the mGlu5 allosteric pocket.
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Affiliation(s)
- James A R Dalton
- Laboratory of Molecular Neuropharmacology and Bioinformatics, Institut de Neurociències and Unitat de Bioestadística, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain.,Network Biomedical Research Centre on Mental Health (CIBERSAM), Madrid, Spain
| | - Jean-Philippe Pin
- Institute of Functional Genomics, Université de Montpellier, Unité Mixte de Recherche 5302 CNRS, Montpellier, France.,Unité de recherche U1191, INSERM, Montpellier, France
| | - Jesús Giraldo
- Laboratory of Molecular Neuropharmacology and Bioinformatics, Institut de Neurociències and Unitat de Bioestadística, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain. .,Network Biomedical Research Centre on Mental Health (CIBERSAM), Madrid, Spain.
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25
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Leach K, Gregory KJ. Molecular insights into allosteric modulation of Class C G protein-coupled receptors. Pharmacol Res 2017; 116:105-118. [DOI: 10.1016/j.phrs.2016.12.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 11/18/2016] [Accepted: 12/07/2016] [Indexed: 12/23/2022]
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26
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Dione I, Deteix J, Briffard T, Chamberland E, Doyon N. Improved Simulation of Electrodiffusion in the Node of Ranvier by Mesh Adaptation. PLoS One 2016; 11:e0161318. [PMID: 27548674 PMCID: PMC4993505 DOI: 10.1371/journal.pone.0161318] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 08/03/2016] [Indexed: 01/19/2023] Open
Abstract
In neural structures with complex geometries, numerical resolution of the Poisson-Nernst-Planck (PNP) equations is necessary to accurately model electrodiffusion. This formalism allows one to describe ionic concentrations and the electric field (even away from the membrane) with arbitrary spatial and temporal resolution which is impossible to achieve with models relying on cable theory. However, solving the PNP equations on complex geometries involves handling intricate numerical difficulties related either to the spatial discretization, temporal discretization or the resolution of the linearized systems, often requiring large computational resources which have limited the use of this approach. In the present paper, we investigate the best ways to use the finite elements method (FEM) to solve the PNP equations on domains with discontinuous properties (such as occur at the membrane-cytoplasm interface). 1) Using a simple 2D geometry to allow comparison with analytical solution, we show that mesh adaptation is a very (if not the most) efficient way to obtain accurate solutions while limiting the computational efforts, 2) We use mesh adaptation in a 3D model of a node of Ranvier to reveal details of the solution which are nearly impossible to resolve with other modelling techniques. For instance, we exhibit a non linear distribution of the electric potential within the membrane due to the non uniform width of the myelin and investigate its impact on the spatial profile of the electric field in the Debye layer.
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Affiliation(s)
- Ibrahima Dione
- Département de mathématiques et de statistique/Groupe Interdisciplinaire de Recherche en Éléments Finis (GIREF), Université Laval, Québec, Québec, Canada
- Neurosciences cellulaires et moléculaires/Institut universitaire en santé mentale de Québec (CRIUSMQ), Université Laval, Québec, Québec, Canada
| | - Jean Deteix
- Département de mathématiques et de statistique/Groupe Interdisciplinaire de Recherche en Éléments Finis (GIREF), Université Laval, Québec, Québec, Canada
| | - Thomas Briffard
- Département de mathématiques et de statistique/Groupe Interdisciplinaire de Recherche en Éléments Finis (GIREF), Université Laval, Québec, Québec, Canada
| | - Eric Chamberland
- Département de mathématiques et de statistique/Groupe Interdisciplinaire de Recherche en Éléments Finis (GIREF), Université Laval, Québec, Québec, Canada
| | - Nicolas Doyon
- Département de mathématiques et de statistique/Groupe Interdisciplinaire de Recherche en Éléments Finis (GIREF), Université Laval, Québec, Québec, Canada
- Neurosciences cellulaires et moléculaires/Institut universitaire en santé mentale de Québec (CRIUSMQ), Université Laval, Québec, Québec, Canada
- * E-mail:
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27
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Singhvi A, Liu B, Friedman CJ, Fong J, Lu Y, Huang XY, Shaham S. A Glial K/Cl Transporter Controls Neuronal Receptive Ending Shape by Chloride Inhibition of an rGC. Cell 2016; 165:936-48. [PMID: 27062922 PMCID: PMC4860081 DOI: 10.1016/j.cell.2016.03.026] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 12/04/2015] [Accepted: 03/15/2016] [Indexed: 12/17/2022]
Abstract
Neurons receive input from the outside world or from other neurons through neuronal receptive endings (NREs). Glia envelop NREs to create specialized microenvironments; however, glial functions at these sites are poorly understood. Here, we report a molecular mechanism by which glia control NRE shape and associated animal behavior. The C. elegans AMsh glial cell ensheathes the NREs of 12 neurons, including the thermosensory neuron AFD. KCC-3, a K/Cl transporter, localizes specifically to a glial microdomain surrounding AFD receptive ending microvilli, where it regulates K(+) and Cl(-) levels. We find that Cl(-) ions function as direct inhibitors of an NRE-localized receptor-guanylyl-cyclase, GCY-8, which synthesizes cyclic guanosine monophosphate (cGMP). High cGMP mediates the effects of glial KCC-3 on AFD shape by antagonizing the actin regulator WSP-1/NWASP. Components of this pathway are broadly expressed throughout the nervous system, suggesting that ionic regulation of the NRE microenvironment may be a conserved mechanism by which glia control neuron shape and function.
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Affiliation(s)
- Aakanksha Singhvi
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Bingqian Liu
- Department of Physiology, Weill Medical College, Cornell University, 1300 York Avenue, New York, NY 10065, USA
| | - Christine J Friedman
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Jennifer Fong
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Yun Lu
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Xin-Yun Huang
- Department of Physiology, Weill Medical College, Cornell University, 1300 York Avenue, New York, NY 10065, USA
| | - Shai Shaham
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
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28
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Mahadevan V, Woodin MA. Regulation of neuronal chloride homeostasis by neuromodulators. J Physiol 2016; 594:2593-605. [PMID: 26876607 PMCID: PMC4865579 DOI: 10.1113/jp271593] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 01/10/2016] [Indexed: 01/23/2023] Open
Abstract
KCC2 is the central regulator of neuronal Cl(-) homeostasis, and is critical for enabling strong hyperpolarizing synaptic inhibition in the mature brain. KCC2 hypofunction results in decreased inhibition and increased network hyperexcitability that underlies numerous disease states including epilepsy, neuropathic pain and neuropsychiatric disorders. The current holy grail of KCC2 biology is to identify how we can rescue KCC2 hypofunction in order to restore physiological levels of synaptic inhibition and neuronal network activity. It is becoming increasingly clear that diverse cellular signals regulate KCC2 surface expression and function including neurotransmitters and neuromodulators. In the present review we explore the existing evidence that G-protein-coupled receptor (GPCR) signalling can regulate KCC2 activity in numerous regions of the nervous system including the hypothalamus, hippocampus and spinal cord. We present key evidence from the literature suggesting that GPCR signalling is a conserved mechanism for regulating chloride homeostasis. This evidence includes: (1) the activation of group 1 metabotropic glutamate receptors and metabotropic Zn(2+) receptors strengthens GABAergic inhibition in CA3 pyramidal neurons through a regulation of KCC2; (2) activation of the 5-hydroxytryptamine type 2A serotonin receptors upregulates KCC2 cell surface expression and function, restores endogenous inhibition in motoneurons, and reduces spasticity in rats; and (3) activation of A3A-type adenosine receptors rescues KCC2 dysfunction and reverses allodynia in a model of neuropathic pain. We propose that GPCR-signals are novel endogenous Cl(-) extrusion enhancers that may regulate KCC2 function.
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Affiliation(s)
- Vivek Mahadevan
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Melanie A Woodin
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
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