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Priya, Yadav N, Anand S, Banerjee J, Tripathi M, Chandra PS, Dixit AB. The multifaceted role of Wnt canonical signalling in neurogenesis, neuroinflammation, and hyperexcitability in mesial temporal lobe epilepsy. Neuropharmacology 2024; 251:109942. [PMID: 38570066 DOI: 10.1016/j.neuropharm.2024.109942] [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: 12/15/2023] [Revised: 03/18/2024] [Accepted: 03/29/2024] [Indexed: 04/05/2024]
Abstract
Epilepsy is a neurological disorder characterised by unprovoked, repetitive seizures caused by abnormal neuronal firing. The Wnt/β-Catenin signalling pathway is involved in seizure-induced neurogenesis, aberrant neurogenesis, neuroinflammation, and hyperexcitability associated with epileptic disorder. Wnt/β-Catenin signalling is crucial for early brain development processes including neuronal patterning, synapse formation, and N-methyl-d-aspartate receptor (NMDAR) regulation. Disruption of molecular networks such as Wnt/β-catenin signalling in epilepsy could offer encouraging anti-epileptogenic targets. So, with a better understanding of the canonical Wnt/-Catenin pathway, we highlight in this review the important elements of Wnt/-Catenin signalling specifically in Mesial Temporal Lobe Epilepsy (MTLE) for potential therapeutic targets.
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Affiliation(s)
- Priya
- Dr. B.R Ambedkar Center for Biomedical Research, University of Delhi, Delhi, India
| | - Nitin Yadav
- Dr. B.R Ambedkar Center for Biomedical Research, University of Delhi, Delhi, India
| | - Sneha Anand
- Dr. B.R Ambedkar Center for Biomedical Research, University of Delhi, Delhi, India
| | - Jyotirmoy Banerjee
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Manjari Tripathi
- Department of Neurology, All India Institute of Medical Sciences, New Delhi, India
| | - P Sarat Chandra
- Department of Neurosurgery, All India Institute of Medical Sciences, New Delhi, India
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Burch AM, Garcia JD, O'Leary H, Haas A, Orfila JE, Tiemeier E, Chalmers N, Smith KR, Quillinan N, Herson PS. TRPM2 and CaMKII Signaling Drives Excessive GABAergic Synaptic Inhibition Following Ischemia. J Neurosci 2024; 44:e1762232024. [PMID: 38565288 PMCID: PMC11079974 DOI: 10.1523/jneurosci.1762-23.2024] [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: 09/22/2023] [Revised: 03/13/2024] [Accepted: 03/18/2024] [Indexed: 04/04/2024] Open
Abstract
Excitotoxicity and the concurrent loss of inhibition are well-defined mechanisms driving acute elevation in excitatory/inhibitory (E/I) balance and neuronal cell death following an ischemic insult to the brain. Despite the high prevalence of long-term disability in survivors of global cerebral ischemia (GCI) as a consequence of cardiac arrest, it remains unclear whether E/I imbalance persists beyond the acute phase and negatively affects functional recovery. We previously demonstrated sustained impairment of long-term potentiation (LTP) in hippocampal CA1 neurons correlating with deficits in learning and memory tasks in a murine model of cardiac arrest/cardiopulmonary resuscitation (CA/CPR). Here, we use CA/CPR and an in vitro ischemia model to elucidate mechanisms by which E/I imbalance contributes to ongoing hippocampal dysfunction in male mice. We reveal increased postsynaptic GABAA receptor (GABAAR) clustering and function in the CA1 region of the hippocampus that reduces the E/I ratio. Importantly, reduced GABAAR clustering observed in the first 24 h rebounds to an elevation of GABAergic clustering by 3 d postischemia. This increase in GABAergic inhibition required activation of the Ca2+-permeable ion channel transient receptor potential melastatin-2 (TRPM2), previously implicated in persistent LTP and memory deficits following CA/CPR. Furthermore, we find Ca2+-signaling, likely downstream of TRPM2 activation, upregulates Ca2+/calmodulin-dependent protein kinase II (CaMKII) activity, thereby driving the elevation of postsynaptic inhibitory function. Thus, we propose a novel mechanism by which inhibitory synaptic strength is upregulated in the context of ischemia and identify TRPM2 and CaMKII as potential pharmacological targets to restore perturbed synaptic plasticity and ameliorate cognitive function.
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Affiliation(s)
- Amelia M Burch
- Neuronal Injury & Plasticity Program, Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Joshua D Garcia
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Heather O'Leary
- Neuronal Injury & Plasticity Program, Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Ami Haas
- Neuronal Injury & Plasticity Program, Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - James E Orfila
- Department of Neurological Surgery, The Ohio State University College of Medicine, Columbus, Ohio 43210
| | - Erika Tiemeier
- Neuronal Injury & Plasticity Program, Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Nicholas Chalmers
- Neuronal Injury & Plasticity Program, Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Katharine R Smith
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Nidia Quillinan
- Neuronal Injury & Plasticity Program, Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Paco S Herson
- Department of Neurological Surgery, The Ohio State University College of Medicine, Columbus, Ohio 43210
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Richardot WH, Hamzai L, Ghukasyan T, Dodder NG, Quintana PJ, Matt GE, Sant KE, Lopez-Galvez N, Hoh E. Novel chemical contaminants associated with thirdhand smoke in settled house dust. CHEMOSPHERE 2024; 352:141138. [PMID: 38272136 DOI: 10.1016/j.chemosphere.2024.141138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 01/03/2024] [Accepted: 01/04/2024] [Indexed: 01/27/2024]
Abstract
Thirdhand smoke (THS) is the persistent and toxic residue from tobacco smoke in indoor environments. A comprehensive understanding of the chemical constituents of THS is necessary to assess the risks of long-term exposure and to establish reliable THS tracers. The objective of this study was to investigate compounds associated with THS through nontargeted analysis (NTA) of settled house dust samples from smokers' and non-smokers' homes, using comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC/TOF-MS). Compounds that were either only present in dust from smokers' homes or that had significantly larger abundance than in non-smokers' homes were termed qualified compounds. We identified 140 qualified compounds, and of these, 42 compounds were tentatively identified by searching matching mass spectra in NIST electron impact (EI) mass spectral library including 20 compounds confirmed with their authentic standards. Among the 42 compounds, 26 compounds were statistically more abundant (p < 0.10) in dust from homes of smokers; seven were tobacco-specific compounds, two of which (nornicotyrine, 3-ethenylpyridine) have not been reported before in house dust. Two compounds, tris (2-chloroethyl) phosphate (a toxic compound used as a flame retardant and reported in tobacco) and propanoic acid, 2-methyl-, 1-(1,1-dimethylethyl)-2-methyl-1,3-propanediyl ester (highly abundant and reported in exhaled air of smokers), were found in dust from all smokers' homes and in zero non-smokers' homes, making these potential THS tracers, possibly associated with recent smoking. Benzyl methyl ketone was significantly higher in dust in smokers' homes, and was previously reported not as a product of tobacco but rather as a form of methamphetamine. This compound was recently reported in mainstream tobacco smoke condensate through NTA as well. These identified potential tracers and chemical components of THS in this study can be further investigated for use in developing THS contamination and exposure assessments.
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Affiliation(s)
- William H Richardot
- School of Public Health, San Diego State University, 5500 Campanile Dr, San Diego, CA, 92182-4162, USA; San Diego State University Research Foundation, 5250 Campanile Dr., San Diego, CA, 92182, USA
| | - Laila Hamzai
- School of Public Health, San Diego State University, 5500 Campanile Dr, San Diego, CA, 92182-4162, USA
| | - Tigran Ghukasyan
- School of Public Health, San Diego State University, 5500 Campanile Dr, San Diego, CA, 92182-4162, USA
| | - Nathan G Dodder
- School of Public Health, San Diego State University, 5500 Campanile Dr, San Diego, CA, 92182-4162, USA; San Diego State University Research Foundation, 5250 Campanile Dr., San Diego, CA, 92182, USA
| | - Penelope Je Quintana
- School of Public Health, San Diego State University, 5500 Campanile Dr, San Diego, CA, 92182-4162, USA
| | - Georg E Matt
- Department of Psychology, San Diego State University, 5500 Campanile Dr, San Diego, CA, 92182-4611, USA
| | - Karilyn E Sant
- School of Public Health, San Diego State University, 5500 Campanile Dr, San Diego, CA, 92182-4162, USA
| | - Nicolas Lopez-Galvez
- School of Public Health, San Diego State University, 5500 Campanile Dr, San Diego, CA, 92182-4162, USA; San Diego State University Research Foundation, 5250 Campanile Dr., San Diego, CA, 92182, USA
| | - Eunha Hoh
- School of Public Health, San Diego State University, 5500 Campanile Dr, San Diego, CA, 92182-4162, USA.
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Chałupnik P, Szymańska E. Kainate Receptor Antagonists: Recent Advances and Therapeutic Perspective. Int J Mol Sci 2023; 24:1908. [PMID: 36768227 PMCID: PMC9916396 DOI: 10.3390/ijms24031908] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/06/2023] [Accepted: 01/16/2023] [Indexed: 01/21/2023] Open
Abstract
Since the 1990s, ionotropic glutamate receptors have served as an outstanding target for drug discovery research aimed at the discovery of new neurotherapeutic agents. With the recent approval of perampanel, the first marketed non-competitive antagonist of AMPA receptors, particular interest has been directed toward 'non-NMDA' (AMPA and kainate) receptor inhibitors. Although the role of AMPA receptors in the development of neurological or psychiatric disorders has been well recognized and characterized, progress in understanding the function of kainate receptors (KARs) has been hampered, mainly due to the lack of specific and selective pharmacological tools. The latest findings in the biology of KA receptors indicate that they are involved in neurophysiological activity and play an important role in both health and disease, including conditions such as anxiety, schizophrenia, epilepsy, neuropathic pain, and migraine. Therefore, we reviewed recent advances in the field of competitive and non-competitive kainate receptor antagonists and their potential therapeutic applications. Due to the high level of structural divergence among the compounds described here, we decided to divide them into seven groups according to their overall structure, presenting a total of 72 active compounds.
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Affiliation(s)
| | - Ewa Szymańska
- Department of Technology and Biotechnology of Drugs, Jagiellonian University Medical College in Kraków, PL 30-688 Kraków, Poland
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Han T, Zhang S, Wei R, Jia G, Wang B, Xu Q, Su J, Jiang C, Jin C. Synthesis and biological evaluation of scutellarein derivatives as neuroprotective agents via activating Nrf2/HO-1 pathway. Fitoterapia 2022; 160:105207. [DOI: 10.1016/j.fitote.2022.105207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 05/05/2022] [Accepted: 05/05/2022] [Indexed: 11/26/2022]
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Volarić J, Szymanski W, Simeth NA, Feringa BL. Molecular photoswitches in aqueous environments. Chem Soc Rev 2021; 50:12377-12449. [PMID: 34590636 PMCID: PMC8591629 DOI: 10.1039/d0cs00547a] [Citation(s) in RCA: 117] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Indexed: 12/17/2022]
Abstract
Molecular photoswitches enable dynamic control of processes with high spatiotemporal precision, using light as external stimulus, and hence are ideal tools for different research areas spanning from chemical biology to smart materials. Photoswitches are typically organic molecules that feature extended aromatic systems to make them responsive to (visible) light. However, this renders them inherently lipophilic, while water-solubility is of crucial importance to apply photoswitchable organic molecules in biological systems, like in the rapidly emerging field of photopharmacology. Several strategies for solubilizing organic molecules in water are known, but there are not yet clear rules for applying them to photoswitchable molecules. Importantly, rendering photoswitches water-soluble has a serious impact on both their photophysical and biological properties, which must be taken into consideration when designing new systems. Altogether, these aspects pose considerable challenges for successfully applying molecular photoswitches in aqueous systems, and in particular in biologically relevant media. In this review, we focus on fully water-soluble photoswitches, such as those used in biological environments, in both in vitro and in vivo studies. We discuss the design principles and prospects for water-soluble photoswitches to inspire and enable their future applications.
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Affiliation(s)
- Jana Volarić
- Centre for Systems Chemistry, Stratingh Institute for Chemistry, Faculty for Science and Engineering, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
| | - Wiktor Szymanski
- Centre for Systems Chemistry, Stratingh Institute for Chemistry, Faculty for Science and Engineering, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
- Department of Radiology, Medical Imaging Center, University of Groningen, University Medical Centre Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - Nadja A Simeth
- Centre for Systems Chemistry, Stratingh Institute for Chemistry, Faculty for Science and Engineering, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
- Institute for Organic and Biomolecular Chemistry, University of Göttingen, Tammannstr. 2, 37077 Göttingen, Germany
| | - Ben L Feringa
- Centre for Systems Chemistry, Stratingh Institute for Chemistry, Faculty for Science and Engineering, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
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Hansen KB, Wollmuth LP, Bowie D, Furukawa H, Menniti FS, Sobolevsky AI, Swanson GT, Swanger SA, Greger IH, Nakagawa T, McBain CJ, Jayaraman V, Low CM, Dell'Acqua ML, Diamond JS, Camp CR, Perszyk RE, Yuan H, Traynelis SF. Structure, Function, and Pharmacology of Glutamate Receptor Ion Channels. Pharmacol Rev 2021; 73:298-487. [PMID: 34753794 PMCID: PMC8626789 DOI: 10.1124/pharmrev.120.000131] [Citation(s) in RCA: 216] [Impact Index Per Article: 72.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Many physiologic effects of l-glutamate, the major excitatory neurotransmitter in the mammalian central nervous system, are mediated via signaling by ionotropic glutamate receptors (iGluRs). These ligand-gated ion channels are critical to brain function and are centrally implicated in numerous psychiatric and neurologic disorders. There are different classes of iGluRs with a variety of receptor subtypes in each class that play distinct roles in neuronal functions. The diversity in iGluR subtypes, with their unique functional properties and physiologic roles, has motivated a large number of studies. Our understanding of receptor subtypes has advanced considerably since the first iGluR subunit gene was cloned in 1989, and the research focus has expanded to encompass facets of biology that have been recently discovered and to exploit experimental paradigms made possible by technological advances. Here, we review insights from more than 3 decades of iGluR studies with an emphasis on the progress that has occurred in the past decade. We cover structure, function, pharmacology, roles in neurophysiology, and therapeutic implications for all classes of receptors assembled from the subunits encoded by the 18 ionotropic glutamate receptor genes. SIGNIFICANCE STATEMENT: Glutamate receptors play important roles in virtually all aspects of brain function and are either involved in mediating some clinical features of neurological disease or represent a therapeutic target for treatment. Therefore, understanding the structure, function, and pharmacology of this class of receptors will advance our understanding of many aspects of brain function at molecular, cellular, and system levels and provide new opportunities to treat patients.
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Affiliation(s)
- Kasper B Hansen
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Lonnie P Wollmuth
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Derek Bowie
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Hiro Furukawa
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Frank S Menniti
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Alexander I Sobolevsky
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Geoffrey T Swanson
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Sharon A Swanger
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Ingo H Greger
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Terunaga Nakagawa
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Chris J McBain
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Vasanthi Jayaraman
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Chian-Ming Low
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Mark L Dell'Acqua
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Jeffrey S Diamond
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Chad R Camp
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Riley E Perszyk
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Hongjie Yuan
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
| | - Stephen F Traynelis
- Center for Structural and Functional Neuroscience, Center for Biomolecular Structure and Dynamics, Division of Biological Sciences, University of Montana, Missoula, MT (K.B.H.); Department of Neurobiology and Behavior, Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY (L.P.W.); Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada (D.B.); WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY (H.F.); MindImmune Therapeutics, Inc., The George & Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI (F.S.M.); Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY (A.I.S.); Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (G.T.S.); Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA and Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (S.A.S.); Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom (I.H.G.); Department of Molecular Physiology and Biophysics, Center for Structural Biology, Vanderbilt Brain Institute, Vanderbilt University, School of Medicine, Nashville, TN (T.N.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.J.M.), and Synaptic Physiology Section, NINDS Intramural Research Program, National Institutes of Health, Bethesda, MD (J.S.D.); Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX (V.J.); Department of Pharmacology, Department of Anaesthesia, Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (C.-M.L.); Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO (M.L.D.); and Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA (C.R.C., R.E.P., H.Y., S.F.T.)
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Narayan SK, Grace Cherian S, Babu Phaniti P, Babu Chidambaram S, Rachel Vasanthi AH, Arumugam M. Preclinical animal studies in ischemic stroke: Challenges and some solutions. Animal Model Exp Med 2021; 4:104-115. [PMID: 34179718 PMCID: PMC8212819 DOI: 10.1002/ame2.12166] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Accepted: 01/28/2021] [Indexed: 01/01/2023] Open
Abstract
Despite the impressive efficacies demonstrated in preclinical research, hundreds of potentially neuroprotective drugs have failed to provide effective neuroprotection for ischemic stroke in human clinical trials. Lack of a powerful animal model for human ischemic stroke could be a major reason for the failure to develop successful neuroprotective drugs for ischemic stroke. This review recapitulates the available cerebral ischemia animal models, provides an anatomical comparison of the circle of Willis of each species, and describes the functional assessment tests used in these ischemic stroke models. The distinct differences between human ischemic stroke and experimental stroke in available animal models is explored. Innovative animal models more closely resembling human strokes, better techniques in functional outcome assessment and better experimental designs generating clearer and stronger evidence may help realise the development of truly neuroprotective drugs that will benefit human ischemic stroke patients. This may involve use of newer molecules or revisiting earlier studies with new experimental designs. Translation of any resultant successes may then be tested in human clinical trials with greater confidence and optimism.
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Affiliation(s)
- Sunil K. Narayan
- Comprehensive Stroke Care and Neurobiology Centre, Department of NeurologyJawaharlal Institute of Postgraduate Medical Education and ResearchPuducherryIndia
| | - Simy Grace Cherian
- Comprehensive Stroke Care and Neurobiology Centre, Department of NeurologyJawaharlal Institute of Postgraduate Medical Education and ResearchPuducherryIndia
| | - Prakash Babu Phaniti
- Department of Biotechnology & School of Medical SciencesUniversity of HyderabadHyderabadIndia
| | | | | | - Murugesan Arumugam
- Comprehensive Stroke Care and Neurobiology Centre, Department of NeurologyJawaharlal Institute of Postgraduate Medical Education and ResearchPuducherryIndia
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9
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Nakae S, Kumon M, Murayama K, Ohba S, Sasaki H, Inamasu J, Kuwahara K, Yamada S, Abe M, Hirose Y. Association of preoperative seizures with tumor metabolites quantified by magnetic resonance spectroscopy in gliomas. Sci Rep 2021; 11:7927. [PMID: 33846339 PMCID: PMC8041994 DOI: 10.1038/s41598-021-86487-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 03/16/2021] [Indexed: 02/02/2023] Open
Abstract
Seizures are common in patients with gliomas; however, the mechanisms of epileptogenesis in gliomas have not been fully understood. This study hypothesized that analyzing quantified metabolites using magnetic resonance spectroscopy (MRS) might provide novel insights to better understand the epileptogenesis in gliomas, and specific metabolites might be indicators of preoperative seizures in gliomas. We retrospectively investigated patient information (gender, age at diagnosis of tumor, their survival time) and tumor information (location, histology, genetic features, and metabolites according to MRS) in patients with gliomas. The data were correlated with the incidence of seizure and analyzed statistically. Of 146 adult supratentorial gliomas, isocitrate dehydrogenase (IDH) mutant tumors significantly indicated higher incidence of preoperative seizures than IDH wild-type gliomas. However, MRS study indicated that glutamate concentration in IDH wild-type gliomas was higher than that in IDH mutant gliomas. Glutamate was not associated with high frequency of preoperative seizures in patients with gliomas. Instead, increased total N-acetyl-L-aspartate (tNAA) was significantly associated with them. Moreover, multivariable analysis indicated that increased level of tNAA was an independent predictor of preoperative seizures. According to MRS analysis, tNAA, rather than glutamate, might be a useful to detect preoperative seizures in patient with supratentorial gliomas.
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Affiliation(s)
- Shunsuke Nakae
- Department of Neurosurgery, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan.
| | - Masanobu Kumon
- Department of Neurosurgery, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
| | - Kazuhiro Murayama
- Department of Radiology, Fujita Health University, Toyoake, Aichi, Japan
| | - Shigeo Ohba
- Department of Neurosurgery, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
| | - Hikaru Sasaki
- Department of Neurosurgery, Keio University, Tokyo, Japan
| | - Joji Inamasu
- Department of Neurosurgery, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
| | - Kiyonori Kuwahara
- Department of Neurosurgery, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
| | - Seiji Yamada
- Department of Pathology, Fujita Health University, Toyoake, Aichi, Japan
| | - Masato Abe
- Department of Pathology, Fujita Health University, Toyoake, Aichi, Japan
| | - Yuichi Hirose
- Department of Neurosurgery, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
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10
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Sowa ST, Vela-Rodríguez C, Galera-Prat A, Cázares-Olivera M, Prunskaite-Hyyryläinen R, Ignatev A, Lehtiö L. A FRET-based high-throughput screening platform for the discovery of chemical probes targeting the scaffolding functions of human tankyrases. Sci Rep 2020; 10:12357. [PMID: 32704068 PMCID: PMC7378079 DOI: 10.1038/s41598-020-69229-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 07/02/2020] [Indexed: 12/13/2022] Open
Abstract
Tankyrases catalyse poly-ADP-ribosylation of their binding partners and the modification serves as a signal for the subsequent proteasomal degradation of these proteins. Tankyrases thereby regulate the turnover of many proteins involved in multiple and diverse cellular processes, such as mitotic spindle formation, telomere homeostasis and Wnt/β-catenin signalling. In recent years, tankyrases have become attractive targets for the development of inhibitors as potential therapeutics against cancer and fibrosis. Further, it has become clear that tankyrases are not only enzymes, but also act as scaffolding proteins forming large cellular signalling complexes. While many potent and selective tankyrase inhibitors of the poly-ADP-ribosylation function exist, the inhibition of tankyrase scaffolding functions remains scarcely explored. In this work we present a robust, simple and cost-effective high-throughput screening platform based on FRET for the discovery of small molecule probes targeting the protein–protein interactions of tankyrases. Validatory screening with the platform led to the identification of two compounds with modest binding affinity to the tankyrase 2 ARC4 domain, demonstrating the applicability of this approach. The platform will facilitate identification of small molecules binding to tankyrase ARC or SAM domains and help to advance a structure-guided development of improved chemical probes targeting tankyrase oligomerization and substrate protein interactions.
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Affiliation(s)
- Sven T Sowa
- Faculty for Biochemistry and Molecular Medicine & Biocenter Oulu, University of Oulu, Oulu, Finland
| | - Carlos Vela-Rodríguez
- Faculty for Biochemistry and Molecular Medicine & Biocenter Oulu, University of Oulu, Oulu, Finland
| | - Albert Galera-Prat
- Faculty for Biochemistry and Molecular Medicine & Biocenter Oulu, University of Oulu, Oulu, Finland
| | - Mariana Cázares-Olivera
- Faculty for Biochemistry and Molecular Medicine & Biocenter Oulu, University of Oulu, Oulu, Finland
| | | | - Alexander Ignatev
- Faculty for Biochemistry and Molecular Medicine & Biocenter Oulu, University of Oulu, Oulu, Finland
| | - Lari Lehtiö
- Faculty for Biochemistry and Molecular Medicine & Biocenter Oulu, University of Oulu, Oulu, Finland.
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11
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Ionotropic Glutamate Receptors in Epilepsy: A Review Focusing on AMPA and NMDA Receptors. Biomolecules 2020; 10:biom10030464. [PMID: 32197322 PMCID: PMC7175173 DOI: 10.3390/biom10030464] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/13/2020] [Accepted: 03/14/2020] [Indexed: 12/22/2022] Open
Abstract
It is widely accepted that glutamate-mediated neuronal hyperexcitation plays a causative role in eliciting seizures. Among glutamate receptors, the roles of N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors in physiological and pathological conditions represent major clinical research targets. It is well known that agonists of NMDA or AMPA receptors can elicit seizures in animal or human subjects, while antagonists have been shown to inhibit seizures in animal models, suggesting a potential role for NMDA and AMPA receptor antagonists in anti-seizure drug development. Several such drugs have been evaluated in clinical studies; however, the majority, mainly NMDA-receptor antagonists, failed to demonstrate adequate efficacy and safety for therapeutic use, and only an AMPA-receptor antagonist, perampanel, has been approved for the treatment of some forms of epilepsy. These results suggest that a misunderstanding of the role of each glutamate receptor in the ictogenic process may underlie the failure of these drugs to demonstrate clinical efficacy and safety. Accumulating knowledge of both NMDA and AMPA receptors, including pathological gene mutations, roles in autoimmune epilepsy, and evidence from drug-discovery research and pharmacological studies, may provide valuable information enabling the roles of both receptors in ictogenesis to be reconsidered. This review aimed to integrate information from several studies in order to further elucidate the specific roles of NMDA and AMPA receptors in epilepsy.
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12
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Radiosynthesis and preliminary evaluation of 11C-labeled 4-cyclopropyl-7-(3-methoxyphenoxy)-3,4-dihydro-2 H-benzo[ e] [1,2,4] thiadiazine 1,1-dioxide for PET imaging AMPA receptors. Tetrahedron Lett 2020; 61. [PMID: 32153306 DOI: 10.1016/j.tetlet.2020.151635] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The α-amino-3-hydroxyl-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) belong to the family of ionotropic transmembrane receptors for glutamate (iGluRs) that are implicated in the pathology of neurological disorders and neurodegenerative diseases. Inspired by a recently developed positive allosteric modulator of AMPARs, 4-cyclopropyl-7-(3-methoxyphenoxy)-3,4-dihydro-2H-benzo[ e ][1,2,4]thiadiazine 1,1-dioxide (16; EC50 = 2.0 nM), we designed a new synthetic route for N-protected phenolic precursor 13 and efficiently radiolabeled a PET ligand [11C]AMPA-1905 ([11C]16) using a modified one-pot two-step strategy in high radiochemical yield and high molar activity. Preliminary in vivo evaluation was carried out to investigate the suitability of [11C]16 as a potential PET probe for AMPAR imaging.
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13
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Dudić A, Reiner A. Quinoxalinedione deprotonation is important for glutamate receptor binding. Biol Chem 2019; 400:927-938. [PMID: 30903748 DOI: 10.1515/hsz-2018-0464] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 03/15/2019] [Indexed: 01/27/2023]
Abstract
Quinoxalinediones are an important class of competitive antagonists at ionotropic glutamate receptors (iGluRs), where they are widely used to block α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate receptor responses. In this study we utilize two prototypic quinoxalinedione antagonists, namely DNQX and CNQX, which quench the intrinsic fluorescence of the ligand binding domain (LBD), to perform in vitro binding assays. We find that binding of DNQX and CNQX at the AMPA receptor GluA2 LBD is strongly pH dependent, whereas glutamate binding is not affected by pH. We also show that the deprotonation of DNQX, CNQX and other quinoxalinediones (NBQX and YM90K) occurs close to physiological pH, which can be explained by the lactam-lactim tautomerization of the quinoxalinedione scaffold. Analysis of our binding data indicates that quinoxalinedione deprotonation is a key requirement for binding, as we find a >100-fold higher affinity for binding of the monoanionic form compared to the neutral form. This suggests a large electrostatic contribution to the interaction with a conserved arginine residue located in the binding pocket of iGluRs. The strong pH dependence of quinoxalinedione binding, which has not previously been reported, is relevant for structure-function studies, but also for the use of quinoxalinediones in physiological experiments and envisioned therapeutic applications.
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Affiliation(s)
- Adela Dudić
- Department of Biology and Biotechnology, Ruhr University Bochum, Universitätsstrasse 150, D-44801 Bochum, Germany
| | - Andreas Reiner
- Department of Biology and Biotechnology, Ruhr University Bochum, Universitätsstrasse 150, D-44801 Bochum, Germany
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14
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Zhao Y, Chen S, Swensen AC, Qian WJ, Gouaux E. Architecture and subunit arrangement of native AMPA receptors elucidated by cryo-EM. Science 2019; 364:355-362. [PMID: 30975770 DOI: 10.1126/science.aaw8250] [Citation(s) in RCA: 118] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 03/26/2019] [Indexed: 12/11/2022]
Abstract
Glutamate-gated AMPA receptors mediate the fast component of excitatory signal transduction at chemical synapses throughout all regions of the mammalian brain. AMPA receptors are tetrameric assemblies composed of four subunits, GluA1-GluA4. Despite decades of study, the subunit composition, subunit arrangement, and molecular structure of native AMPA receptors remain unknown. Here we elucidate the structures of 10 distinct native AMPA receptor complexes by single-particle cryo-electron microscopy (cryo-EM). We find that receptor subunits are arranged nonstochastically, with the GluA2 subunit preferentially occupying the B and D positions of the tetramer and with triheteromeric assemblies comprising a major population of native AMPA receptors. Cryo-EM maps define the structure for S2-M4 linkers between the ligand-binding and transmembrane domains, suggesting how neurotransmitter binding is coupled to ion channel gating.
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Affiliation(s)
- Yan Zhao
- Vollum Institute, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Shanshuang Chen
- Vollum Institute, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Adam C Swensen
- Integrative Omics, Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Wei-Jun Qian
- Integrative Omics, Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Eric Gouaux
- Vollum Institute, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA. .,Howard Hughes Medical Institute, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
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15
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Chen Z, Mori W, Zhang X, Yamasaki T, Dunn PJ, Zhang G, Fu H, Shao T, Zhang Y, Hatori A, Ma L, Fujinaga M, Xie L, Deng X, Li H, Yu Q, Rong J, Josephson L, Ma JA, Shao Y, Tomita S, Zhang MR, Liang SH. Synthesis, pharmacology and preclinical evaluation of 11C-labeled 1,3-dihydro-2H-benzo[d]imidazole-2-ones for imaging γ8-dependent transmembrane AMPA receptor regulatory protein. Eur J Med Chem 2018; 157:898-908. [PMID: 30145376 DOI: 10.1016/j.ejmech.2018.08.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 08/04/2018] [Accepted: 08/06/2018] [Indexed: 11/20/2022]
Abstract
a-Amino-3-hydroxyl-5-methyl-4-isoxazolepropionic acid (AMPA) receptors are implicated in the pathology of neurological diseases such as epilepsy and schizophrenia. As pan antagonists for this target are often accompanied with undesired effects at high doses, one of the recent drug discovery approaches has shifted to subtype-selective AMPA receptor (AMPAR) antagonists, specifically, via modulating transmembrane AMPAR regulatory proteins (TARPs). The quantification of AMPARs by positron emission tomography (PET) would help obtain insights into disease conditions in the living brain and advance the translational development of AMPAR antagonists. Herein we report the design, synthesis and preclinical evaluation of a series of TARP γ-8 antagonists, amenable for radiolabeling, for the development of subtype-selective AMPAR PET imaging agents. Based on the pharmacology evaluation, molecular docking studies and physiochemical properties, we have identified several promising lead compounds 3, 17-19 and 21 for in vivo PET studies. All candidate compounds were labeled with [11C]COCl2 in high radiochemical yields (13-31% RCY) and high molar activities (35-196 GBq/μmol). While tracers 30 ([11C]17) &32 ([11C]21) crossed the blood-brain barrier and showed heterogeneous distribution in PET studies, consistent with TARP γ-8 expression, high nonspecific binding prevented further evaluation. To our delight, tracer 31 ([11C]3) showed good in vitro specific binding and characteristic high uptake in the hippocampus in rat brain tissues, which provides the guideline for further development of a new generation subtype selective TARP γ-8 dependent AMPAR tracers.
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Affiliation(s)
- Zhen Chen
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA; Department of Chemistry, School of Science, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Wakana Mori
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Xiaofei Zhang
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Tomoteru Yamasaki
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Patrick J Dunn
- Department of Cellular and Molecular Physiology, Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Genwei Zhang
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Hualong Fu
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Tuo Shao
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Yiding Zhang
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Akiko Hatori
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Longle Ma
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Masayuki Fujinaga
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Lin Xie
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Xiaoyun Deng
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Hua Li
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Qingzhen Yu
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Jian Rong
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Lee Josephson
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Jun-An Ma
- Department of Chemistry, School of Science, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Yihan Shao
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Susumu Tomita
- Department of Cellular and Molecular Physiology, Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Ming-Rong Zhang
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan.
| | - Steven H Liang
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA.
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16
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Lee MR, Gardinier KM, Gernert DL, Schober DA, Wright RA, Wang H, Qian Y, Witkin JM, Nisenbaum ES, Kato AS. Structural Determinants of the γ-8 TARP Dependent AMPA Receptor Antagonist. ACS Chem Neurosci 2017; 8:2631-2647. [PMID: 28825787 DOI: 10.1021/acschemneuro.7b00186] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The forebrain specific AMPA receptor antagonist, LY3130481/CERC-611, which selectively antagonizes the AMPA receptors associated with TARP γ-8, an auxiliary subunit enriched in the forebrain, has potent antiepileptic activities without motor side effects. We designated the compounds with such activities as γ-8 TARP dependent AMPA receptor antagonists (γ-8 TDAAs). In this work, we further investigated the mechanisms of action using a radiolabeled γ-8 TDAA and ternary structural modeling with mutational validations to characterize the LY3130481 binding to γ-8. The radioligand binding to the cells heterologously expressing GluA1 and/or γ-8 revealed that γ-8 TDAAs binds to γ-8 alone without AMPA receptors. Homology modeling of γ-8, based on the crystal structures of a distant TARP homologue, murine claudin 19, in conjunction with knowledge of two γ-8 residues previously identified as critical for the LY3130481 TARP-dependent selectivity provided the basis for a binding mode prediction. This allowed further rational mutational studies for characterization of the structural determinants in TARP γ-8 for LY3130481 activities, both thermodynamically as well as kinetically.
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Affiliation(s)
- Matthew R. Lee
- Lilly
Biotechnology Center, Eli Lilly and Company, 10300 Campus Point Dr. #200, San Diego, California 92121, United States
| | - Kevin M. Gardinier
- Neuroscience
Discovery, Lilly Research Laboratory, 355 E Merril St., Indianapolis, Indiana 46285, United States
| | - Douglas L. Gernert
- Neuroscience
Discovery, Lilly Research Laboratory, 355 E Merril St., Indianapolis, Indiana 46285, United States
| | - Douglas A. Schober
- Neuroscience
Discovery, Lilly Research Laboratory, 355 E Merril St., Indianapolis, Indiana 46285, United States
| | - Rebecca A. Wright
- Neuroscience
Discovery, Lilly Research Laboratory, 355 E Merril St., Indianapolis, Indiana 46285, United States
| | - He Wang
- Neuroscience
Discovery, Lilly Research Laboratory, 355 E Merril St., Indianapolis, Indiana 46285, United States
| | - Yuewei Qian
- Neuroscience
Discovery, Lilly Research Laboratory, 355 E Merril St., Indianapolis, Indiana 46285, United States
| | - Jeffrey M. Witkin
- Neuroscience
Discovery, Lilly Research Laboratory, 355 E Merril St., Indianapolis, Indiana 46285, United States
| | - Eric S. Nisenbaum
- Neuroscience
Discovery, Lilly Research Laboratory, 355 E Merril St., Indianapolis, Indiana 46285, United States
| | - Akihiko S. Kato
- Neuroscience
Discovery, Lilly Research Laboratory, 355 E Merril St., Indianapolis, Indiana 46285, United States
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17
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Demmer CS, Rombach D, Liu N, Nielsen B, Pickering DS, Bunch L. Revisiting the Quinoxalinedione Scaffold in the Construction of New Ligands for the Ionotropic Glutamate Receptors. ACS Chem Neurosci 2017; 8:2477-2495. [PMID: 28872835 DOI: 10.1021/acschemneuro.7b00243] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
More than two decades ago, the quinoxalinedione scaffold was shown to act as an α-amino acid bioisoster. Following extensive structure-activity relationship (SAR) studies, the antagonists DNQX, CNQX, and NBQX in the ionotropic glutamate receptor field were identified. In this work, we revisit the quinoxalinedione scaffold and explore the incorporation of an acid functionality in the 6-position. The SAR studies disclose that by this strategy it was possible to tune in iGluR selectivity among the AMPA, NMDA, and KA receptors, and to some extent also obtain full receptor subtype selectivity. Highlights of the study of 44 new analogues are compound 2m being a high affinity ligand for native AMPA receptors (IC50= 0.48 μM), analogues 2e,f,h,k,v all displayed selectivity for native NMDA receptors, and compounds 2s,t,u are selective ligand for the GluK1 receptor. Most interestingly, compound 2w was shown to be a GluK3-preferring ligand with full selectivity over native AMPA, KA and NMDA receptors.
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Affiliation(s)
- Charles S. Demmer
- Department of Drug Design and Pharmacology,
Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen OE, Denmark
| | - David Rombach
- Department of Drug Design and Pharmacology,
Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen OE, Denmark
| | - Na Liu
- Department of Drug Design and Pharmacology,
Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen OE, Denmark
| | - Birgitte Nielsen
- Department of Drug Design and Pharmacology,
Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen OE, Denmark
| | - Darryl S. Pickering
- Department of Drug Design and Pharmacology,
Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen OE, Denmark
| | - Lennart Bunch
- Department of Drug Design and Pharmacology,
Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen OE, Denmark
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18
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Karsy M, Brock A, Guan J, Taussky P, Kalani MYS, Park MS. Neuroprotective strategies and the underlying molecular basis of cerebrovascular stroke. Neurosurg Focus 2017; 42:E3. [DOI: 10.3171/2017.1.focus16522] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Stroke is a leading cause of disability in the US. Although there has been significant progress in the area of medical and surgical thrombolytic technologies, neuroprotective agents to prevent secondary cerebral injury and to minimize disability remain limited. Only limited success has been reported in preclinical and clinical trials evaluating a variety of compounds. In this review, the authors discuss the most up-to-date information regarding the underlying molecular biology of stroke as well as strategies that aim to mitigate this complex signaling cascade. Results of historical research trials involving N-methyl-d-aspartate and α-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptor antagonists, clomethiazole, antioxidants, citicoline, nitric oxide, and immune regulators have laid the groundwork for current progress. In addition, more recent studies involving therapeutic hypothermia, magnesium, albumin, glyburide, uric acid, and a variety of other treatments have provided more options. The use of neuroprotective agents in combination or with existing thrombolytic treatments may be one of many exciting areas of further development. Although past trials of neuroprotective agents in ischemic stroke have been limited, significant insights into mechanisms of stroke, animal models, and trial design have incrementally improved approaches for future therapies.
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19
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The fate of medications evaluated for ischemic stroke pharmacotherapy over the period 1995-2015. Acta Pharm Sin B 2016; 6:522-530. [PMID: 27818918 PMCID: PMC5071630 DOI: 10.1016/j.apsb.2016.06.013] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 05/26/2016] [Accepted: 05/31/2016] [Indexed: 01/26/2023] Open
Abstract
Stroke is a brain damage caused by a loss of blood supply to a portion of the brain, which requires prompt and effective treatment. The current pharmacotherapy for ischemic stroke primarily relies on thrombolysis using recombinant tissue plasminogen activators (rt-PAs) to breakdown blood clots. Neuroprotective agents that inhibit excitatory neurotransmitters are also used to treat ischemic stroke but have failed to translate into clinical benefits. This poses a major challenge in biomedical research to understand what causes the progressive brain cell death after stroke and how to develop an effective pharmacotherapy for stroke. This brief review analyzes the fate of about 430 potentially useful stroke medications over the period 1995–2015 and describes in detail those that successfully reached the market. Hopefully, the information from this analysis will shed light on how future stroke research can improve stroke drug discovery.
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Key Words
- ADP, adenosine diphosphate
- AMPA, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid
- ASIC1a, acid-sensing ion channel 1a
- BDNF, brain-derived neurotrophic factor
- CFDA, the China Food and Drug Administration
- CNTF, ciliary neurotrophic factor
- GDNF, glial cell line–derived neurotrophic factor
- Ion channel
- Ischemic stroke
- MHRA, Medicine and Healthcare Products Regulatory Agency
- NBP, butylphthalide/3-n-butylphthalide
- NGF, nerve growth factor
- NMDA, N-methyl-D-aspartate
- Neuroprotective agent
- Non-NMDA mechanism
- TCM, traditional Chinese medicine
- TRP, transient receptor potential
- TRPC, transient receptor potential canonical
- TRPM, transient receptor potential melastatin
- TRPV, transient receptor potential vanilloid
- Thrombosis
- Traditional Chinese medicine
- iGluRs, ionotropic glutamate receptors
- rt-Pas, recombinant tissue plasminogen activators
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20
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21
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Wang P, Li GC, Jain P, Farmer ME, He J, Shen PX, Yu JQ. Ligand-Promoted meta-C-H Amination and Alkynylation. J Am Chem Soc 2016; 138:14092-14099. [PMID: 27712063 DOI: 10.1021/jacs.6b08942] [Citation(s) in RCA: 152] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Using a modified norbornene (methyl bicyclo[2.2.1]hept-2-ene-2-carboxylate) as a transient mediator, meta-C-H amination and meta-C-H alkynylation of aniline and phenol substrates have been developed for the first time. Both the identification of a monoprotected 3-amino-2-hydroxypyridine/pyridone-type ligand and the use of a modified norbornene as a mediator are crucial for the realization of these two unprecedented meta-C-H transformations. A variety of substrates are compatible with both meta-C-H amination and meta-C-H alkynylation. Amination and alkynylation of heterocyclic substrates including indole, indoline, and indazole afford the desired products in moderate to high yields.
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Affiliation(s)
- Peng Wang
- Department of Chemistry, The Scripps Research Institute , 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
| | - Gen-Cheng Li
- Department of Chemistry, The Scripps Research Institute , 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
| | - Pankaj Jain
- Department of Chemistry, The Scripps Research Institute , 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
| | - Marcus E Farmer
- Department of Chemistry, The Scripps Research Institute , 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
| | - Jian He
- Department of Chemistry, The Scripps Research Institute , 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
| | - Peng-Xiang Shen
- Department of Chemistry, The Scripps Research Institute , 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
| | - Jin-Quan Yu
- Department of Chemistry, The Scripps Research Institute , 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
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22
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Barber DM, Liu SA, Gottschling K, Sumser M, Hollmann M, Trauner D. Optical control of AMPA receptors using a photoswitchable quinoxaline-2,3-dione antagonist. Chem Sci 2016; 8:611-615. [PMID: 28451208 PMCID: PMC5358534 DOI: 10.1039/c6sc01621a] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 08/01/2016] [Indexed: 02/02/2023] Open
Abstract
We have developed the first photoswitchable AMPA receptor antagonist, termed ShuBQX-3. It permits the precise optical control of AMPA receptors and exhibits a remarkable red-shifting of its photoswitching properties when bound to the receptor.
AMPA receptors respond to the neurotransmitter glutamate and play a critical role in excitatory neurotransmission. They have been implicated in several psychiatric disorders and have rich pharmacology. Antagonists of AMPA receptors have been explored as drugs and one has even reached the clinic. We now introduce a freely diffusible photoswitchable antagonist that is selective for AMPA receptors and endows them with light-sensitivity. Our photoswitch, ShuBQX-3, is active in its dark-adapted trans-isoform but is significantly less active as its cis-isoform. ShuBQX-3 exhibits a remarkable red-shifting of its photoswitching properties through interactions with the AMPA receptor ligand binding site. Since it can be used to control action potential firing with light, it could emerge as a powerful tool for studying synaptic transmission with high spatial and temporal precision.
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Affiliation(s)
- David M Barber
- Department of Chemistry and Center for Integrated Protein Science , Ludwig Maximilians University Munich , Butenandtstraße 5-13 , 81377 Munich , Germany .
| | - Shu-An Liu
- Department of Chemistry and Center for Integrated Protein Science , Ludwig Maximilians University Munich , Butenandtstraße 5-13 , 81377 Munich , Germany .
| | - Kevin Gottschling
- Department of Biochemistry I - Receptor Biochemistry , Ruhr-Universität-Bochum , Bochum 44780 , Germany
| | - Martin Sumser
- Department of Chemistry and Center for Integrated Protein Science , Ludwig Maximilians University Munich , Butenandtstraße 5-13 , 81377 Munich , Germany .
| | - Michael Hollmann
- Department of Biochemistry I - Receptor Biochemistry , Ruhr-Universität-Bochum , Bochum 44780 , Germany
| | - Dirk Trauner
- Department of Chemistry and Center for Integrated Protein Science , Ludwig Maximilians University Munich , Butenandtstraße 5-13 , 81377 Munich , Germany .
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23
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Zhao Y, Chen S, Yoshioka C, Baconguis I, Gouaux E. Architecture of fully occupied GluA2 AMPA receptor-TARP complex elucidated by cryo-EM. Nature 2016; 536:108-11. [PMID: 27368053 DOI: 10.1038/nature18961] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 06/24/2016] [Indexed: 11/09/2022]
Abstract
Fast excitatory neurotransmission in the mammalian central nervous system is largely carried out by AMPA-sensitive ionotropic glutamate receptors. Localized within the postsynaptic density of glutamatergic spines, AMPA receptors are composed of heterotetrameric receptor assemblies associated with auxiliary subunits, the most common of which are transmembrane AMPA receptor regulatory proteins (TARPs). The association of TARPs with AMPA receptors modulates receptor trafficking and the kinetics of receptor gating and pharmacology. Here we report the cryo-electron microscopy (cryo-EM) structure of the homomeric rat GluA2 AMPA receptor saturated with TARP γ2 subunits, which shows how the TARPs are arranged with four-fold symmetry around the ion channel domain and make extensive interactions with the M1, M2 and M4 transmembrane helices. Poised like partially opened ‘hands’ underneath the two-fold symmetric ligand-binding domain (LBD) 'clamshells', one pair of TARPs is juxtaposed near the LBD dimer interface, whereas the other pair is near the LBD dimer-dimer interface. The extracellular ‘domains’ of TARP are positioned to not only modulate LBD clamshell closure, but also affect conformational rearrangements of the LBD layer associated with receptor activation and desensitization, while the TARP transmembrane domains buttress the ion channel pore.
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24
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Szymanska E, Frydenvang K, Pickering DS, Krintel C, Nielsen B, Kooshki A, Zachariassen LG, Olsen L, Kastrup JS, Johansen TN. Studies on Aryl-Substituted Phenylalanines: Synthesis, Activity, and Different Binding Modes at AMPA Receptors. J Med Chem 2015; 59:448-61. [PMID: 26653877 DOI: 10.1021/acs.jmedchem.5b01666] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A series of racemic aryl-substituted phenylalanines was synthesized and evaluated in vitro at recombinant rat GluA1-3, at GluK1-3, and at native AMPA receptors. The individual enantiomers of two target compounds, (RS)-2-amino-3-(3,4-dichloro-5-(5-hydroxypyridin-3-yl)phenyl)propanoic acid 37 and (RS)-2-amino-3-(3'-hydroxybiphenyl-3-yl)propanoic acid 38, were characterized. (S)-37 and (R)-38 were identified as the only biologically active isomers, both being antagonists at GluA2 receptors with Kb of 1.80 and 3.90 μM, respectively. To address this difference in enantiopharmacology, not previously seen for amino acid-based AMPA receptor antagonists, X-ray crystal structures of both eutomers in complex with the GluA2 ligand binding domain were solved. The cocrystal structures of (S)-37 and (R)-38 showed similar interactions of the amino acid parts but unexpected and different orientations and interactions of the biaromatic parts of the ligands inside the binding site, with (R)-38 having a binding mode not previously identified for amino acid-based antagonists.
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Affiliation(s)
- Ewa Szymanska
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen , 2100 Copenhagen, Denmark
| | - Karla Frydenvang
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen , 2100 Copenhagen, Denmark
| | - Darryl S Pickering
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen , 2100 Copenhagen, Denmark
| | - Christian Krintel
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen , 2100 Copenhagen, Denmark
| | - Birgitte Nielsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen , 2100 Copenhagen, Denmark
| | - Ayesheh Kooshki
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen , 2100 Copenhagen, Denmark
| | - Linda G Zachariassen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen , 2100 Copenhagen, Denmark
| | - Lars Olsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen , 2100 Copenhagen, Denmark
| | - Jette S Kastrup
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen , 2100 Copenhagen, Denmark
| | - Tommy N Johansen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen , 2100 Copenhagen, Denmark
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25
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Oi N, Tokunaga M, Suzuki M, Nagai Y, Nakatani Y, Yamamoto N, Maeda J, Minamimoto T, Zhang MR, Suhara T, Higuchi M. Development of Novel PET Probes for Central 2-Amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic Acid Receptors. J Med Chem 2015; 58:8444-62. [DOI: 10.1021/acs.jmedchem.5b00712] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Norihito Oi
- Tsukuba
Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba, Ibaraki 300-2635, Japan
- Molecular
Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, Chiba 263-8555, Japan
| | - Masaki Tokunaga
- Molecular
Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, Chiba 263-8555, Japan
| | - Michiyuki Suzuki
- Tsukuba
Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba, Ibaraki 300-2635, Japan
- Molecular
Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, Chiba 263-8555, Japan
| | - Yuji Nagai
- Molecular
Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, Chiba 263-8555, Japan
| | - Yosuke Nakatani
- Tsukuba
Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba, Ibaraki 300-2635, Japan
- Molecular
Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, Chiba 263-8555, Japan
| | - Noboru Yamamoto
- Tsukuba
Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba, Ibaraki 300-2635, Japan
| | - Jun Maeda
- Molecular
Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, Chiba 263-8555, Japan
| | - Takafumi Minamimoto
- Molecular
Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, Chiba 263-8555, Japan
| | - Ming-Rong Zhang
- Molecular
Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, Chiba 263-8555, Japan
| | - Tetsuya Suhara
- Molecular
Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, Chiba 263-8555, Japan
| | - Makoto Higuchi
- Molecular
Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, Chiba 263-8555, Japan
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26
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Synthesis, structure-activity relationships, and anticonvulsant activities of 2-amino-4H-pyrido[3,2-e][1,3]thiazin-4-one derivatives as orally active AMPA receptor antagonists. Bioorg Med Chem 2015; 23:1788-99. [PMID: 25792143 DOI: 10.1016/j.bmc.2015.02.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 02/16/2015] [Accepted: 02/17/2015] [Indexed: 11/23/2022]
Abstract
As part of a program aimed at discovering orally active 2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid (AMPA) receptor antagonists, we screened our compound library and identified 2-[allyl(4-methylphenyl)amino]-4H-pyrido[3,2-e][1,3]thiazin-4-one (7) as a lead compound that inhibited kainate-induced neurotoxicity mediated by AMPA receptors in rat hippocampal cultures. Structure-activity relationship studies of a series of 2-amino-4H-pyrido[3,2-e][1,3]thiazin-4-one derivatives revealed that substituents on the phenyl ring attached to the 2-amino group and the 4H-pyrido[3,2-e][1,3]thiazin-4-one ring system play an important role in inhibitory activity against kainate-induced neurotoxicity. Several analogs bearing a phenyl group with a 4-substituent or five- or six-membered ring fused at the 3,4-positions exhibited potent inhibitory activity against kainate-induced neurotoxicity. Further, some of these compounds exhibited significant suppression of maximal electroshock seizure in mice following oral administration. Of these compounds, 2-[(4-chlorophenyl)(methyl)amino]-4H-pyrido[3,2-e][1,3]thiazin-4-one (16i) (YM928) demonstrated the most potent inhibitory effect with an ED50 value of 7.4mg/kg.
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27
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Meyerson JR, Kumar J, Chittori S, Rao P, Pierson J, Bartesaghi A, Mayer ML, Subramaniam S. Structural mechanism of glutamate receptor activation and desensitization. Nature 2014; 514:328-34. [PMID: 25119039 PMCID: PMC4199900 DOI: 10.1038/nature13603] [Citation(s) in RCA: 181] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 06/19/2014] [Indexed: 01/04/2023]
Abstract
Ionotropic glutamate receptors are ligand-gated ion channels that mediate excitatory synaptic transmission in the vertebrate brain. To gain a better understanding of how structural changes gate ion flux across the membrane, we trapped rat AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid) and kainate receptor subtypes in their major functional states and analysed the resulting structures using cryo-electron microscopy. We show that transition to the active state involves a 'corkscrew' motion of the receptor assembly, driven by closure of the ligand-binding domain. Desensitization is accompanied by disruption of the amino-terminal domain tetramer in AMPA, but not kainate, receptors with a two-fold to four-fold symmetry transition in the ligand-binding domains in both subtypes. The 7.6 Å structure of a desensitized kainate receptor shows how these changes accommodate channel closing. These findings integrate previous physiological, biochemical and structural analyses of glutamate receptors and provide a molecular explanation for key steps in receptor gating.
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Affiliation(s)
- Joel R Meyerson
- Laboratory of Cell Biology, Center for Cancer Research, NCI, NIH, Bethesda, Maryland 20892, USA
| | - Janesh Kumar
- Laboratory of Cellular and Molecular Neurophysiology, Porter Neuroscience Research Center, NICHD, NIH, Bethesda, Maryland 20892, USA
| | - Sagar Chittori
- Laboratory of Cellular and Molecular Neurophysiology, Porter Neuroscience Research Center, NICHD, NIH, Bethesda, Maryland 20892, USA
| | - Prashant Rao
- Laboratory of Cell Biology, Center for Cancer Research, NCI, NIH, Bethesda, Maryland 20892, USA
| | | | - Alberto Bartesaghi
- Laboratory of Cell Biology, Center for Cancer Research, NCI, NIH, Bethesda, Maryland 20892, USA
| | - Mark L Mayer
- Laboratory of Cellular and Molecular Neurophysiology, Porter Neuroscience Research Center, NICHD, NIH, Bethesda, Maryland 20892, USA
| | - Sriram Subramaniam
- Laboratory of Cell Biology, Center for Cancer Research, NCI, NIH, Bethesda, Maryland 20892, USA
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28
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Wang C, Han Y, Wu A, Sólyom S, Niu L. Mechanism and site of inhibition of AMPA receptors: pairing a thiadiazole with a 2,3-benzodiazepine scaffold. ACS Chem Neurosci 2014; 5:138-47. [PMID: 24313227 DOI: 10.1021/cn400193u] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
2,3-Benzodiazepine compounds are synthesized as drug candidates for treatment of various neurological disorders involving excessive activity of AMPA receptors. Here we report that pairing a thiadiazole moiety with a 2,3-benzodiazepine scaffold via the N-3 position yields an inhibitor type with >28-fold better potency and selectivity on AMPA receptors than the 2,3-benzodiazepine scaffold alone. Using whole-cell recording, we characterized two thiadiazolyl compounds, that is, one contains a 1,3,4-thiadiazole moiety and the other contains a 1,2,4-thiadiazole-3-one moiety. These compounds exhibit potent, equal inhibition of both the closed-channel and the open-channel conformations of all four homomeric AMPA receptor channels and two GluA2R-containing complex AMPA receptor channels. Furthermore, these compounds bind to the same receptor site as GYKI 52466 does, a site we previously termed as the "M" site. A thiadiazole moiety is thought to occupy more fully the side pocket of the receptor site or the "M" site, thereby generating a stronger, multivalent interaction between the inhibitor and the receptor binding site. We suggest that, as a heterocycle, a thiadiazole can be further modified chemically to produce a new class of even more potent, noncompetitive inhibitors of AMPA receptors.
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Affiliation(s)
- Congzhou Wang
- Department of Chemistry, and Center for Neuroscience Research, University at Albany, SUNY, Albany, New York 12222, United States
| | - Yan Han
- Department of Chemistry, and Center for Neuroscience Research, University at Albany, SUNY, Albany, New York 12222, United States
| | - Andrew Wu
- Department of Chemistry, and Center for Neuroscience Research, University at Albany, SUNY, Albany, New York 12222, United States
| | - Sándor Sólyom
- CF Pharma Pharmaceutical Manufacturing Co., Ltd, H-1097 Budapest, Kén
utca 5, Hungary
| | - Li Niu
- Department of Chemistry, and Center for Neuroscience Research, University at Albany, SUNY, Albany, New York 12222, United States
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29
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Lau AY, Salazar H, Blachowicz L, Ghisi V, Plested AJR, Roux B. A conformational intermediate in glutamate receptor activation. Neuron 2013; 79:492-503. [PMID: 23931998 DOI: 10.1016/j.neuron.2013.06.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/05/2013] [Indexed: 11/28/2022]
Abstract
Ionotropic glutamate receptors (iGluRs) transduce the chemical signal of neurotransmitter release into membrane depolarization at excitatory synapses in the brain. The opening of the transmembrane ion channel of these ligand-gated receptors is driven by conformational transitions that are induced by the association of glutamate molecules to the ligand-binding domains (LBDs). Here, we describe the crystal structure of a GluA2 LBD tetramer in a configuration that involves an ∼30° rotation of the LBD dimers relative to the crystal structure of the full-length receptor. The configuration is stabilized by an engineered disulfide crosslink. Biochemical and electrophysiological studies on full-length receptors incorporating either this crosslink or an engineered metal bridge show that this LBD configuration corresponds to an intermediate state of receptor activation. GluA2 activation therefore involves a combination of both intra-LBD (cleft closure) and inter-LBD dimer conformational transitions. Overall, these results provide a comprehensive structural characterization of an iGluR intermediate state.
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Affiliation(s)
- Albert Y Lau
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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30
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Rogawski MA. AMPA receptors as a molecular target in epilepsy therapy. Acta Neurol Scand 2013:9-18. [PMID: 23480151 DOI: 10.1111/ane.12099] [Citation(s) in RCA: 155] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/04/2013] [Indexed: 11/28/2022]
Abstract
Epileptic seizures occur as a result of episodic abnormal synchronous discharges in cerebral neuronal networks. Although a variety of non-conventional mechanisms may play a role in epileptic synchronization, cascading excitation within networks of synaptically connected excitatory glutamatergic neurons is a classical mechanism. As is the case throughout the central nervous system, fast synaptic excitation within and between brain regions relevant to epilepsy is mediated predominantly by AMPA receptors. By inhibiting glutamate-mediated excitation, AMPA receptor antagonists markedly reduce or abolish epileptiform activity in in vitro preparations and confer seizure protection in a broad range of animal seizure models. NMDA receptors may also contribute to epileptiform activity, but NMDA receptor blockade is not sufficient to eliminate epileptiform discharges. AMPA receptors move into and out of the synapse in a dynamic fashion in forms of synaptic plasticity, underlying learning and memory. Often, the trigger for these dynamic movements is the activation of NMDA receptors. While NMDA receptor antagonists inhibit these forms of synaptic plasticity, AMPA receptor antagonists do not impair synaptic plasticity and do not inhibit memory formation or retrieval. The demonstrated clinical efficacy of perampanel, a high-potency, orally active non-competitive AMPA receptor antagonist, supports the concept that AMPA receptors are critical to epileptic synchronization and the generation and spread of epileptic discharges in human epilepsy.
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Affiliation(s)
- M. A. Rogawski
- Department of Neurology; School of Medicine and Center for Neuroscience; University of California, Davis; Sacramento; CA; USA
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31
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Hibi S, Ueno K, Nagato S, Kawano K, Ito K, Norimine Y, Takenaka O, Hanada T, Yonaga M. Discovery of 2-(2-Oxo-1-phenyl-5-pyridin-2-yl-1,2-dihydropyridin-3-yl)benzonitrile (Perampanel): A Novel, Noncompetitive α-Amino-3-hydroxy-5-methyl-4-isoxazolepropanoic Acid (AMPA) Receptor Antagonist. J Med Chem 2012. [PMID: 23181587 DOI: 10.1021/jm301268u] [Citation(s) in RCA: 123] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shigeki Hibi
- Medicinal
Chemistry, ‡Biopharmacology, and §Drug Metabolism and Pharmacokinetics,
Tsukuba Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-shi, Ibaraki 300-2635, Japan
| | - Koshi Ueno
- Medicinal
Chemistry, ‡Biopharmacology, and §Drug Metabolism and Pharmacokinetics,
Tsukuba Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-shi, Ibaraki 300-2635, Japan
| | - Satoshi Nagato
- Medicinal
Chemistry, ‡Biopharmacology, and §Drug Metabolism and Pharmacokinetics,
Tsukuba Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-shi, Ibaraki 300-2635, Japan
| | - Koki Kawano
- Medicinal
Chemistry, ‡Biopharmacology, and §Drug Metabolism and Pharmacokinetics,
Tsukuba Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-shi, Ibaraki 300-2635, Japan
| | - Koichi Ito
- Medicinal
Chemistry, ‡Biopharmacology, and §Drug Metabolism and Pharmacokinetics,
Tsukuba Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-shi, Ibaraki 300-2635, Japan
| | - Yoshihiko Norimine
- Medicinal
Chemistry, ‡Biopharmacology, and §Drug Metabolism and Pharmacokinetics,
Tsukuba Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-shi, Ibaraki 300-2635, Japan
| | - Osamu Takenaka
- Medicinal
Chemistry, ‡Biopharmacology, and §Drug Metabolism and Pharmacokinetics,
Tsukuba Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-shi, Ibaraki 300-2635, Japan
| | - Takahisa Hanada
- Medicinal
Chemistry, ‡Biopharmacology, and §Drug Metabolism and Pharmacokinetics,
Tsukuba Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-shi, Ibaraki 300-2635, Japan
| | - Masahiro Yonaga
- Medicinal
Chemistry, ‡Biopharmacology, and §Drug Metabolism and Pharmacokinetics,
Tsukuba Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-shi, Ibaraki 300-2635, Japan
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32
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Webb SM, Vollrath-Smith FR, Shin R, Jhou TC, Xu S, Ikemoto S. Rewarding and incentive motivational effects of excitatory amino acid receptor antagonists into the median raphe and adjacent regions of the rat. Psychopharmacology (Berl) 2012; 224:401-12. [PMID: 22752328 PMCID: PMC3498528 DOI: 10.1007/s00213-012-2759-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2012] [Accepted: 05/31/2012] [Indexed: 12/23/2022]
Abstract
RATIONALE The motivational process that regulates approach behavior toward salient distal stimuli (i.e., incentive motivation) plays a key role in voluntary behavior and motivational disorders such as addiction. This process may be mediated by many neurotransmitter systems and a network of many brain structures, including the median and dorsal raphe regions (MR and DR, respectively). OBJECTIVE We sought to examine whether the blockade of excitatory amino acid receptors in the MR and DR is rewarding, using intracranial self-administration, and whether the self-administration effect can be explained by drug's effectiveness to enhance incentive motivation, using a visual sensation seeking procedure. RESULTS Rats learned to self-administer the AMPA receptor antagonist ZK 200775 into the vicinity of the MR, DR, or medial oral pontine reticular regions, but not the ventral tegmental area. The NMDA receptor antagonist AP5 was also self-administered into the MR, while it was not readily self-administered into other regions. When ZK 200775 was noncontingently administered into the MR, rats markedly increased approach responses rewarded by brief illumination of a light stimulus. In addition, contingent administration of ZK 200775 into the MR induced a conditioning effect on approach responses. CONCLUSIONS Rats self-administer excitatory amino acid receptor antagonists into the MR and adjacent regions. Self-administration effect of AMPA receptor antagonists into the MR can be largely explained by the manipulation's properties to invigorate ongoing approach behavior and induces conditioned approach. Glutamatergic afferents to the median raphe and adjacent regions appear to tonically suppress incentive-motivational processes.
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Affiliation(s)
- Sierra M. Webb
- Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| | - Fiori R. Vollrath-Smith
- Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| | - Rick Shin
- Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| | - Thomas C. Jhou
- Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| | - Shengping Xu
- Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| | - Satoshi Ikemoto
- Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
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33
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Russo E, Gitto R, Citraro R, Chimirri A, De Sarro G. New AMPA antagonists in epilepsy. Expert Opin Investig Drugs 2012; 21:1371-89. [DOI: 10.1517/13543784.2012.705277] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Emilio Russo
- University “Magna Graecia” of Catanzaro, School of Medicine, Science of Health Department,
Catanzaro, Italy
| | - Rosaria Gitto
- University of Messina, Farmaco-Chimico Department,
Messina, Italy
| | - Rita Citraro
- University “Magna Graecia” of Catanzaro, School of Medicine, Science of Health Department,
Catanzaro, Italy
| | - Alba Chimirri
- University of Messina, Farmaco-Chimico Department,
Messina, Italy
| | - Giovambattista De Sarro
- University “Magna Graecia” of Catanzaro, School of Medicine, Science of Health Department,
Catanzaro, Italy
- University of Catanzaro, School of Medicine, Department of Experimental and Clinical Medicine,
Via T. Campanella, 115, 88100 Catanzaro, Italy ;
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34
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Midgett CR, Gill A, Madden DR. Domain architecture of a calcium-permeable AMPA receptor in a ligand-free conformation. Front Mol Neurosci 2012; 4:56. [PMID: 22232575 PMCID: PMC3249379 DOI: 10.3389/fnmol.2011.00056] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 12/10/2011] [Indexed: 11/22/2022] Open
Abstract
Ligand-gated ion channels couple the free energy of agonist binding to the gating of selective transmembrane ion pores, permitting cells to regulate ion flux in response to external chemical stimuli. However, the stereochemical mechanisms responsible for this coupling remain obscure. In the case of the ionotropic glutamate receptors (iGluRs), the modular nature of receptor subunits has facilitated structural analysis of the N-terminal domain (NTD), and of multiple conformations of the ligand-binding domain (LBD). Recently, the crystallographic structure of an antagonist-bound form of the receptor was determined. However, disulfide trapping of this conformation blocks channel opening, suggesting that channel activation involves additional quaternary packing arrangements. To explore the conformational space available to iGluR channels, we report here a second, clearly distinct domain architecture of homotetrameric, calcium-permeable AMPA receptors, determined by single-particle electron microscopy of untagged and fluorescently tagged constructs in a ligand-free state. It reveals a novel packing of NTD dimers, and a separation of LBD dimers across a central vestibule. In this arrangement, which reconciles diverse functional observations, agonist-induced cleft closure across LBD dimers can be converted into a twisting motion that provides a basis for receptor activation.
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Affiliation(s)
- Charles R Midgett
- Department of Biochemistry, Dartmouth Medical School Hanover, NH, USA
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Harada S, Fujita-Hamabe W, Tokuyama S. Ischemic Stroke and Glucose Intolerance: a Review of the Evidence and Exploration of Novel Therapeutic Targets. J Pharmacol Sci 2012; 118:1-13. [DOI: 10.1254/jphs.11r04cr] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 09/21/2011] [Indexed: 10/14/2022] Open
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Deng P, Xu ZC. Contribution of Ih to Neuronal Damage in the Hippocampus after Traumatic Brain Injury in Rats. J Neurotrauma 2011; 28:1173-83. [DOI: 10.1089/neu.2010.1683] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Affiliation(s)
- Ping Deng
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana
| | - Zao C. Xu
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana
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Ritz M, Wang C, Micale N, Ettari R, Niu L. Mechanism of Inhibition of the GluA2 AMPA Receptor Channel Opening: the Role of 4-Methyl versus 4-Carbonyl Group on the Diazepine Ring of 2,3-Benzodiazepine Derivatives. ACS Chem Neurosci 2011; 2:506-513. [PMID: 22059113 DOI: 10.1021/cn200033j] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
2,3-Benzodiazepine derivatives are synthesized as drug candidates for a potential treatment of various neurodegenerative diseases involving the excessive activity of AMPA receptors. Here, we describe a rapid kinetic investigation of the mechanism of inhibition of the GluA2Q(flip) AMPA receptor channel opening by two 2,3-benzodiazepine derivatives, i.e. the prototypic 2,3-benzodiazepine compound GYKI 52466 [(1-(4-aminophenyl)-4-methyl-7,8-methylenedioxy-5H-2,3-benzodiazepine)] and 1-(4-aminophenyl)-3,5-dihydro-7,8-methylenedioxy-4H-2,3-benzodiazepin-4-one (BDZ-2). GYKI 52466 and BDZ-2 are structurally similar in that the 4-methyl group in the diazepine ring of GYKI 52466 is replaced by a carbonyl group, yielding BDZ-2. Using a laser-pulse photolysis technique with ∼60 μs time resolution, we characterize the effect of the two compounds individually on the channel-opening process of the GluA2Q(flip) receptor expressed in HEK-293 cells. We find that BDZ-2 preferentially inhibits the open-channel state, whereas GYKI 52466 is more selective for the closed-channel state of the GluA2Q(flip) receptors. Each inhibitor binds independently to its own noncompetitive site, yet the two sites do not interact allosterically. The significance of these results in the context of both the structure-activity relationship and the properties of the GluA2Q(flip) receptor channels is presented.
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Affiliation(s)
- Mark Ritz
- Department of Chemistry, and Center for Neuroscience Research, University at Albany, SUNY, Albany, New York 12222, United States
| | - Congzhou Wang
- Department of Chemistry, and Center for Neuroscience Research, University at Albany, SUNY, Albany, New York 12222, United States
| | - Nicola Micale
- Dipartimento Farmaco-Chimico, Università di Messina, viale Annunziata, 98168 Messina, Italy
| | - Roberta Ettari
- Dipartimento Farmaco-Chimico, Università di Messina, viale Annunziata, 98168 Messina, Italy
| | - Li Niu
- Department of Chemistry, and Center for Neuroscience Research, University at Albany, SUNY, Albany, New York 12222, United States
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The hidden energetics of ligand binding and activation in a glutamate receptor. Nat Struct Mol Biol 2011; 18:283-7. [PMID: 21317895 PMCID: PMC3075596 DOI: 10.1038/nsmb.2010] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Accepted: 11/30/2010] [Indexed: 02/07/2023]
Abstract
Ionotropic glutamate receptors (iGluRs) are ligand-gated ion channels that mediate the majority of excitatory synaptic transmission in the central nervous system. The free energy of neurotransmitter-binding to the ligand-binding domains (LBDs) of iGluRs is converted into useful work to drive receptor activation. Here, the principal thermodynamic contributions from ligand-docking and ligand-induced LBD closure are computed for nine ligands of GluA2 using all-atom molecular dynamics free energy simulations. The results are validated by a comparison with experimentally measured apparent affinities to the isolated LBD. Features in the free energy landscapes governing LBD closure are critical determinants of binding free energies. An analysis of accessible LBD conformations transposed into the context of an intact GluA2 receptor reveals that the relative displacement of specific diagonal subunits in the tetrameric structure may be key to the action of partial agonists.
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Dissection of mitogenic and neurodegenerative actions of cystine and glutamate in malignant gliomas. Oncogene 2011; 30:43-53. [PMID: 20802520 DOI: 10.1038/onc.2010.391] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Malignant glioma represents one of the most aggressive and lethal human neoplasias. A hallmark of gliomas is their rapid proliferation and destruction of vital brain tissue, a process in which excessive glutamate release by glioma cells takes center stage. Pharmacologic antagonism with glutamate signaling through ionotropic glutamate receptors attenuates glioma progression in vivo, indicating that glutamate release by glioma cells is a prerequisite for rapid glioma growth. Glutamate has been suggested to promote glioma cell proliferation in an autocrine or paracrine manner, in particular by activation of the (RS)-α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid hydrate (AMPA) subtype of glutamate receptors. Here, we dissect the effects of glutamate secretion on glioma progression. Glioma cells release glutamate through the amino-acid antiporter system X(c)(-), a process that is mechanistically linked with cystine incorporation. We show that disrupting glutamate secretion by interfering with the system X(c)(-) activity attenuates glioma cell proliferation solely cystine dependently, whereas glutamate itself does not augment glioma cell growth in vitro. Neither AMPA receptor agonism nor antagonism affects glioma growth in vitro. On a molecular level, AMPA insensitivity is concordant with a pronounced transcriptional downregulation of AMPA receptor subunits or overexpression of the fully edited GluR2 subunit, both of which block receptor activity. Strikingly, AMPA receptor inhibition in tumor-implanted brain slices resulted in markedly reduced tumor progression associated with alleviated neuronal cell death, suggesting that the ability of glutamate to promote glioma progression strictly requires the tumor microenvironment. Concerning a potential pharmacotherapy, targeting system X(c)(-) activity disrupts two major pathophysiological properties of glioma cells, that is, the induction of excitotoxic neuronal cell death and incorporation of cystine required for rapid proliferation.
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Wei Y, Yemisci M, Kim HH, Yung LM, Shin HK, Hwang SK, Guo S, Qin T, Alsharif N, Brinkmann V, Liao JK, Lo EH, Waeber C. Fingolimod provides long-term protection in rodent models of cerebral ischemia. Ann Neurol 2010; 69:119-29. [PMID: 21280082 DOI: 10.1002/ana.22186] [Citation(s) in RCA: 224] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Revised: 06/30/2010] [Accepted: 07/30/2010] [Indexed: 12/29/2022]
Abstract
OBJECTIVE The sphingosine-1-phosphate (S1P) receptor agonist fingolimod (FTY720), that has shown efficacy in advanced multiple sclerosis clinical trials, decreases reperfusion injury in heart, liver, and kidney. We therefore tested the therapeutic effects of fingolimod in several rodent models of focal cerebral ischemia. To assess the translational significance of these findings, we asked whether fingolimod improved long-term behavioral outcomes, whether delayed treatment was still effective, and whether neuroprotection can be obtained in a second species. METHODS We used rodent models of middle cerebral artery occlusion and cell-culture models of neurotoxicity and inflammation to examine the therapeutic potential and mechanisms of neuroprotection by fingolimod. RESULTS In a transient mouse model, fingolimod reduced infarct size, neurological deficit, edema, and the number of dying cells in the core and periinfarct area. Neuroprotection was accompanied by decreased inflammation, as fingolimod-treated mice had fewer activated neutrophils, microglia/macrophages, and intercellular adhesion molecule-1 (ICAM-1)-positive blood vessels. Fingolimod-treated mice showed a smaller infarct and performed better in behavioral tests up to 15 days after ischemia. Reduced infarct was observed in a permanent model even when mice were treated 4 hours after ischemic onset. Fingolimod also decreased infarct size in a rat model of focal ischemia. Fingolimod did not protect primary neurons against glutamate excitotoxicity or hydrogen peroxide, but decreased ICAM-1 expression in brain endothelial cells stimulated by tumor necrosis factor alpha. INTERPRETATION These findings suggest that anti-inflammatory mechanisms, and possibly vasculoprotection, rather than direct effects on neurons, underlie the beneficial effects of fingolimod after stroke. S1P receptors are a highly promising target in stroke treatment.
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Affiliation(s)
- Ying Wei
- Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
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Mattes H, Carcache D, Kalkman HO, Koller M. alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) antagonists: from bench to bedside. J Med Chem 2010; 53:5367-82. [PMID: 20356304 DOI: 10.1021/jm901688m] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Henri Mattes
- Novartis Pharma AG, Werk Klybeck, WKL-122-241 Postfach, CH-4002 Basel, Switzerland.
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Traynelis SF, Wollmuth LP, McBain CJ, Menniti FS, Vance KM, Ogden KK, Hansen KB, Yuan H, Myers SJ, Dingledine R. Glutamate receptor ion channels: structure, regulation, and function. Pharmacol Rev 2010; 62:405-96. [PMID: 20716669 PMCID: PMC2964903 DOI: 10.1124/pr.109.002451] [Citation(s) in RCA: 2553] [Impact Index Per Article: 182.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The mammalian ionotropic glutamate receptor family encodes 18 gene products that coassemble to form ligand-gated ion channels containing an agonist recognition site, a transmembrane ion permeation pathway, and gating elements that couple agonist-induced conformational changes to the opening or closing of the permeation pore. Glutamate receptors mediate fast excitatory synaptic transmission in the central nervous system and are localized on neuronal and non-neuronal cells. These receptors regulate a broad spectrum of processes in the brain, spinal cord, retina, and peripheral nervous system. Glutamate receptors are postulated to play important roles in numerous neurological diseases and have attracted intense scrutiny. The description of glutamate receptor structure, including its transmembrane elements, reveals a complex assembly of multiple semiautonomous extracellular domains linked to a pore-forming element with striking resemblance to an inverted potassium channel. In this review we discuss International Union of Basic and Clinical Pharmacology glutamate receptor nomenclature, structure, assembly, accessory subunits, interacting proteins, gene expression and translation, post-translational modifications, agonist and antagonist pharmacology, allosteric modulation, mechanisms of gating and permeation, roles in normal physiological function, as well as the potential therapeutic use of pharmacological agents acting at glutamate receptors.
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Affiliation(s)
- Stephen F Traynelis
- Department of Pharmacology, Emory University School of Medicine, Rollins Research Center, 1510 Clifton Road, Atlanta, GA 30322-3090, USA.
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Bergholz R, Staks T, Rüther K. Effects of the AMPA antagonist ZK 200775 on visual function: a randomized controlled trial. PLoS One 2010; 5:e12111. [PMID: 20711429 PMCID: PMC2920815 DOI: 10.1371/journal.pone.0012111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Accepted: 06/10/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND ZK 200775 is an antagonist at the alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptor and had earned attention as a possible neuroprotective agent in cerebral ischemia. Probands receiving the agent within phase I trials reported on an alteration of visual perception. In this trial, the effects of ZK 200775 on the visual system were analyzed in detail. METHODOLOGY In a randomised controlled trial we examined eyes and vision before and after the intravenous administration of two different doses of ZK 200775 and placebo. There were 3 groups of 6 probands each: Group 1 recieved 0.03 mg/kg/h, group 2 0.75 mg/kg/h of ZK 200775, the control group received 0.9% sodium chloride solution. Probands were healthy males aged between 57 and 69 years. The following methods were applied: clinical examination, visual acuity, ophthalmoscopy, colour vision, rod absolute threshold, central visual field, pattern-reversal visual evoked potentials (pVEP), ON-OFF and full-field electroretinogram (ERG). PRINCIPAL FINDINGS No effect of ZK 200775 was seen on eye position or motility, stereopsis, pupillary function or central visual field testing. Visual acuity and dark vision deteriorated significantly in both treated groups. Color vision was most remarkably impaired. The dark-adapted ERG revealed a reduction of oscillatory potentials (OP) and partly of the a- and b-wave, furthermore an alteration of b-wave morphology and an insignificantly elevated b/a-ratio. Cone-ERG modalities showed decreased amplitudes and delayed implicit times. In the ON-OFF ERG the ON-answer amplitudes increased whereas the peak times of the OFF-answer were reduced. The pattern VEP exhibited lower amplitudes and prolonged peak times. CONCLUSIONS The AMPA receptor blockade led to a strong impairment of typical OFF-pathway functions like color vision and the cone ERG. On the other hand the ON-pathway as measured by dark vision and the scotopic ERG was affected as well. This further elucidates the interdependence of both pathways. TRIAL REGISTRATION ClinicalTrials.gov NCT00999284.
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Affiliation(s)
- Richard Bergholz
- Department of Ophthalmology, Charité Universitätsmedizin Berlin, Campus Virchow-Klinikum, Berlin, Germany.
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Abstract
In the last fifteen years, new antiepileptic medications have been offered for the treatment of patients with epilepsy. Nevertheless, despite optimal medical treatment, up to 30% of patients still experience recurrent seizures and the challenge for new, more efficacious and better-tolerated drugs continues. New antiepileptic drugs include the evolution of pre-existing drugs and new compounds identified through the investigation of additional molecular targets, such as SV2A synaptic vesicle protein, voltage-gated potassium channels, ionotropic and metabotropic glutamate receptors, and gap junctions. This paper reviews the available information on various classes of molecules that are in the pipeline as well as on the innovative approaches to the treatment of epilepsy.
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Affiliation(s)
- Pasquale Striano
- Muscular & Neurodegenerative Diseases Unit, Institute G. Gaslini, Genova, Italy
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X-ray structure, symmetry and mechanism of an AMPA-subtype glutamate receptor. Nature 2010; 462:745-56. [PMID: 19946266 DOI: 10.1038/nature08624] [Citation(s) in RCA: 781] [Impact Index Per Article: 55.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2009] [Accepted: 11/02/2009] [Indexed: 02/06/2023]
Abstract
Ionotropic glutamate receptors mediate most excitatory neurotransmission in the central nervous system and function by opening a transmembrane ion channel upon binding of glutamate. Despite their crucial role in neurobiology, the architecture and atomic structure of an intact ionotropic glutamate receptor are unknown. Here we report the crystal structure of the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)-sensitive, homotetrameric, rat GluA2 receptor at 3.6 A resolution in complex with a competitive antagonist. The receptor harbours an overall axis of two-fold symmetry with the extracellular domains organized as pairs of local dimers and with the ion channel domain exhibiting four-fold symmetry. A symmetry mismatch between the extracellular and ion channel domains is mediated by two pairs of conformationally distinct subunits, A/C and B/D. Therefore, the stereochemical manner in which the A/C subunits are coupled to the ion channel gate is different from the B/D subunits. Guided by the GluA2 structure and site-directed cysteine mutagenesis, we suggest that GluN1 and GluN2A NMDA (N-methyl-d-aspartate) receptors have a similar architecture, with subunits arranged in a 1-2-1-2 pattern. We exploit the GluA2 structure to develop mechanisms of ion channel activation, desensitization and inhibition by non-competitive antagonists and pore blockers.
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Plasminogen activator inhibitor type 1 derived peptide, EEIIMD, diminishes cortical infarct but fails to improve neurological function in aged rats following middle cerebral artery occlusion. Brain Res 2009; 1281:84-90. [PMID: 19465008 DOI: 10.1016/j.brainres.2009.05.042] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Revised: 05/11/2009] [Accepted: 05/13/2009] [Indexed: 11/23/2022]
Abstract
Age is a primary risk factor in stroke that is often overlooked in animal studies. We contend that using aged animals yields insight into aspects of stroke injury and recovery that are masked, or not elicited, in younger animals. In this study, we examined effects of co-administration of a plasminogen activator inhibitor type 1 derived peptide, Glu-Glu-Iso-Iso-Met-Asp (EEIIMD), with tissue plasminogen activator (tPA) on infarct volume and functional outcome in aged rats following a transient middle cerebral artery occlusion. Results of our study showed aged (18-20 months) rats treated with EEIIMD along with tPA had reduced cortical infarction volume. However, aged rats showed no improvement in total infarction volume, edema formation, or functional outcome as compared to aged rats administered only tPA. Young adult rats (3-4 months) treated with EEIIMD showed significant improvement in cortical and total infarction volumes, edema formation, and functional outcome. Striatal infarction volume was unaffected by EEIIMD treatment in both young adult and aged rats. These findings emphasize that physiological differences exist between young adult and aged rats and suggest that taking aging processes into account when assessing stroke may improve our ability to discern which therapeutics can be translated from bench to bedside.
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Chemical and electrochemical procedures for the synthesis of diisopropyltetrahydroquinoxalinedione derivatives. Tetrahedron Lett 2008. [DOI: 10.1016/j.tetlet.2008.06.049] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Sharma A, Mehta VP, Van Hecke K, Van Meervelt L, Van der Eycken E. Synthesis of 5-(phenylsulfanyl)-1,4-dihydropyrazine-2,3-diones via an unexpected microwave-assisted cascade reaction. Tetrahedron Lett 2008. [DOI: 10.1016/j.tetlet.2008.06.063] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Szénási G, Vegh M, Szabo G, Kertesz S, Kapus G, Albert M, Greff Z, Ling I, Barkoczy J, Simig G, Spedding M, Harsing LG. 2,3-Benzodiazepine-type AMPA receptor antagonists and their neuroprotective effects. Neurochem Int 2008; 52:166-83. [PMID: 17707550 DOI: 10.1016/j.neuint.2007.07.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
AMPA receptors are fast ligand-gated members of glutamate receptors in neuronal and many types of non-neuronal cells. The heterotetramer complexes are assembled from four subunits (GluR1-4) in region-, development- and function-selective patterns. Each subunit contains three extracellular domains (a large amino terminal domain, an agonist-binding domain and a transducer domain), and three transmembrane segments with a loop (pore forming domain), as well as the intracellular carboxy terminal tail (traffic and conductance regulatory domain). The binding of the agonist (excitatory amino acids and their derivatives) initiates conformational realignments, which transmit to the transducer domain and membrane spanning segments to gate the channel permeable to Na+, K+ and more or less to Ca2+. Several 2,3-benzodiazepines act as non-competitive antagonists of the AMPA receptor (termed also negative allosteric modulators), which are thought to bind to the transducer domains and inhibit channel gating. Analysing their effects in vitro, it has been possible to recognize a structure-activity relationship, and to describe the critical parts of the molecules involved in their action at AMPA receptors. Blockade of AMPA receptors can protect the brain from apoptotic and necrotic cell death by preventing neuronal excitotoxicity during pathophysiological activation of glutamatergic neurons. Animal experiments provided evidence for the potential usefulness of non-competitive AMPA antagonists in the treatment of human ischemic and neurodegenerative disorders including stroke, multiple sclerosis, Parkinson's disease, periventricular leukomalacia and motoneuron disease. 2,3-benzodiazepine AMPA antagonists can protect against seizures, decrease levodopa-induced dyskinesia in animal models of Parkinson's disease demonstrating their utility for the treatment of a variety of CNS disorders.
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Affiliation(s)
- Gábor Szénási
- Division of Preclinical Research, EGIS Pharmaceuticals Plc, Bokenyfoldi ut 116, 1165 Budapest, Hungary
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Gigler G, Móricz K, ágoston M, Simó A, Albert M, Benedek A, Kapus G, Kertész S, Vegh M, Barkóczy J, Markó B, Szabó G, Matucz É, Gacsályi I, Lévay G, Hársing LG, Szénási G. Neuroprotective and anticonvulsant effects of EGIS-8332, a non-competitive AMPA receptor antagonist, in a range of animal models. Br J Pharmacol 2007; 152:151-60. [PMID: 17603549 PMCID: PMC1978282 DOI: 10.1038/sj.bjp.0707362] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND AND PURPOSE Blockade of AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptors is a good treatment option for a variety of central nervous system disorders. The present study evaluated the neuroprotective and anticonvulsant effects of EGIS-8332, a non-competitive AMPA receptor antagonist, as a potential drug candidate. EXPERIMENTAL APPROACH AMPA antagonist effects of EGIS-8332 were measured using patch-clamp techniques. Neuroprotective and anticonvulsant effects of EGIS-8332 were evaluated in various experimental models, relative to those of GYKI 53405. KEY RESULTS EGIS-8332 inhibited AMPA currents in rat cerebellar Purkinje cells and inhibited the AMPA- and quisqualate-induced excitotoxicity in primary cultures of telencephalon neurons (IC(50)=5.1-9.0 microM), in vitro. Good anticonvulsant actions were obtained in maximal electroshock-, sound- and chemically-induced seizures (range of ED(50)=1.4-14.0 mg kg(-1) i.p.) in mice. Four days after transient global cerebral ischaemia, EGIS-8332 decreased neuronal loss in the hippocampal CA1 area in gerbils and rats. EGIS-8332 dose-dependently reduced cerebral infarct size after permanent middle cerebral artery occlusion in mice and rats (minimum effective dose=3 mg kg(-1) i.p.). Side effects of EGIS-8332 emerged much above its pharmacologically active doses. A tendency for better efficacy of GYKI 53405 than that of EGIS-8332 was observed in anticonvulsant tests that reached statistical significance in few cases, while the contrary was perceived in cerebral ischaemia tests. CONCLUSIONS AND IMPLICATIONS EGIS-8332 seems suitable for further development for the treatment of epilepsy, ischaemia and stroke based on its efficacy in a variety of experimental disease models, and on its low side effect potential.
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Affiliation(s)
- G Gigler
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - K Móricz
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - M ágoston
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - A Simó
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - M Albert
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - A Benedek
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - G Kapus
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - S Kertész
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - M Vegh
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - J Barkóczy
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - B Markó
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - G Szabó
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - É Matucz
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - I Gacsályi
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - G Lévay
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - L G Hársing
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
| | - G Szénási
- Division of Preclinical Research, EGIS Pharmaceuticals PLC Budapest, Hungary
- Author for correspondence:
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