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Sheikh-Bahaei N, Chen M, Pappas I. Magnetic Resonance Spectroscopy (MRS) in Alzheimer's Disease. Methods Mol Biol 2024; 2785:115-142. [PMID: 38427192 DOI: 10.1007/978-1-0716-3774-6_9] [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] [Indexed: 03/02/2024]
Abstract
MRS is a noninvasive technique to measure different metabolites in the brain. Changes in the levels of certain metabolites can be used as surrogate markers for Alzheimer's disease. They can potentially be used for diagnosis, prediction of prognosis, or even assessing response to treatment.There are different techniques for MRS acquisitions including STimulated Echo Acquisition Mode (STEAM) and Point Resolved Spectroscopy (PRESS). In terms of localization, single or multi-voxel methods can be used. Based on current data: 1. NAA, marker of neuronal integrity and viability, reduces in AD with longitudinal changes over the time as the disease progresses. There are data claiming that reduction of NAA is associated with tau accumulation, early neurodegenerative processes, and cognitive decline. Therefore, it can be used as a stage biomarker for AD to assess the severity of the disease. With advancement of disease modifying therapies, there is a potential role for NAA in the future to be used as a marker of response to treatment. 2. mI, marker of glial cell proliferation and activation, is associated with AB pathology and has early changes in the course of the disease. The NAA/mI ratio can be predictive of AD development with high specificity and can be utilized in the clinical setting to stratify cases for further evaluation with PET for potential treatments. 3. The changes in the level of other metabolites such as Chol, Glu, Gln, and GABA are controversial because of the lack of standardization of MRS techniques, current technical limitations, and possible region specific changes. 4. Ultrahigh field MRS and more advanced techniques can overcome many of these limitations and enable us to measure more metabolites with higher accuracy. 5. Standardization of MRS techniques, validation of metabolites' changes against PET using PET-guided technique, and longitudinal follow-ups to investigate the temporal changes of the metabolites in relation to other biomarkers and cognition will be crucial to confirm the utility of MRS as a potential noninvasive biomarker for AD.
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Affiliation(s)
- Nasim Sheikh-Bahaei
- Department of Radiology, Keck School of Medicine of USC, Los Angeles, CA, USA.
| | - Michelle Chen
- Keck School of Medicine of USC, USC, Los Angeles, CA, USA
| | - Ioannis Pappas
- USC Mark and Mary Stevens Neuroimaging and Informatics Institute, USC, Los Angeles, CA, USA
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2
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Dupont AC, Arlicot N, Vercouillie J, Serrière S, Maia S, Bonnet-Brilhault F, Santiago-Ribeiro MJ. Metabotropic Glutamate Receptor Subtype 5 Positron-Emission-Tomography Radioligands as a Tool for Central Nervous System Drug Development: Between Progress and Setbacks. Pharmaceuticals (Basel) 2023; 16:1127. [PMID: 37631042 PMCID: PMC10458693 DOI: 10.3390/ph16081127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 08/03/2023] [Accepted: 08/09/2023] [Indexed: 08/27/2023] Open
Abstract
The metabotropic glutamate receptor subtype 5 (mGluR5) is a class C G-protein-coupled receptor (GPCR) that has been implicated in various neuronal processes and, consequently, in several neuropsychiatric or neurodevelopmental disorders. Over the past few decades, mGluR5 has become a major focus for pharmaceutical companies, as an attractive target for drug development, particularly through the therapeutic potential of its modulators. In particular, allosteric binding sites have been targeted for better specificity and efficacy. In this context, Positron Emission Tomography (PET) appears as a useful tool for making decisions along a drug candidate's development process, saving time and money. Thus, PET provides quantitative information about a potential drug candidate and its target at the molecular level. However, in this area, particular attention has to be given to the interpretation of the PET signal and its conclusions. Indeed, the complex pharmacology of both mGluR5 and radioligands, allosterism, the influence of endogenous glutamate and the choice of pharmacokinetic model are all factors that may influence the PET signal. This review focuses on mGluR5 PET radioligands used at several stages of central nervous system drug development, highlighting advances and setbacks related to the complex pharmacology of these radiotracers.
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Affiliation(s)
- Anne-Claire Dupont
- Radiopharmacie, CHRU de Tours, 37000 Tours, France
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
| | - Nicolas Arlicot
- Radiopharmacie, CHRU de Tours, 37000 Tours, France
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
- CIC 1415, Tours University, INSERM, 37000 Tours, France
| | | | - Sophie Serrière
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
| | - Serge Maia
- Radiopharmacie, CHRU de Tours, 37000 Tours, France
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
| | - Frédérique Bonnet-Brilhault
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
- Excellence Center for Autism and Neurodevelopmental Disorders, CHRU de Tours, 37000 Tours, France
| | - Maria-Joao Santiago-Ribeiro
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
- Nuclear Medicine Department, CHRU de Tours, 37000 Tours, France
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3
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Premi E, Pengo M, Mattioli I, Cantoni V, Dukart J, Gasparotti R, Buratti E, Padovani A, Bocchetta M, Todd EG, Bouzigues A, Cash DM, Convery RS, Russell LL, Foster P, Thomas DL, van Swieten JC, Jiskoot LC, Seelaar H, Galimberti D, Sanchez-Valle R, Laforce R, Moreno F, Synofzik M, Graff C, Masellis M, Tartaglia MC, Rowe JB, Tsvetanov KA, Vandenberghe R, Finger E, Tiraboschi P, de Mendonça A, Santana I, Butler CR, Ducharme S, Gerhard A, Levin J, Otto M, Sorbi S, Le Ber I, Pasquier F, Rohrer JD, Borroni B. Early neurotransmitters changes in prodromal frontotemporal dementia: A GENFI study. Neurobiol Dis 2023; 179:106068. [PMID: 36898614 DOI: 10.1016/j.nbd.2023.106068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 03/01/2023] [Accepted: 03/04/2023] [Indexed: 03/12/2023] Open
Abstract
BACKGROUND Neurotransmitters deficits in Frontotemporal Dementia (FTD) are still poorly understood. Better knowledge of neurotransmitters impairment, especially in prodromal disease stages, might tailor symptomatic treatment approaches. METHODS In the present study, we applied JuSpace toolbox, which allowed for cross-modal correlation of Magnetic Resonance Imaging (MRI)-based measures with nuclear imaging derived estimates covering various neurotransmitter systems including dopaminergic, serotonergic, noradrenergic, GABAergic and glutamatergic neurotransmission. We included 392 mutation carriers (157 GRN, 164 C9orf72, 71 MAPT), together with 276 non-carrier cognitively healthy controls (HC). We tested if the spatial patterns of grey matter volume (GMV) alterations in mutation carriers (relative to HC) are correlated with specific neurotransmitter systems in prodromal (CDR® plus NACC FTLD = 0.5) and in symptomatic (CDR® plus NACC FTLD≥1) FTD. RESULTS In prodromal stages of C9orf72 disease, voxel-based brain changes were significantly associated with spatial distribution of dopamine and acetylcholine pathways; in prodromal MAPT disease with dopamine and serotonin pathways, while in prodromal GRN disease no significant findings were reported (p < 0.05, Family Wise Error corrected). In symptomatic FTD, a widespread involvement of dopamine, serotonin, glutamate and acetylcholine pathways across all genetic subtypes was found. Social cognition scores, loss of empathy and poor response to emotional cues were found to correlate with the strength of GMV colocalization of dopamine and serotonin pathways (all p < 0.01). CONCLUSIONS This study, indirectly assessing neurotransmitter deficits in monogenic FTD, provides novel insight into disease mechanisms and might suggest potential therapeutic targets to counteract disease-related symptoms.
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Affiliation(s)
- Enrico Premi
- Neurology, Department of Neurological and Vision Sciences, ASST Spedali Civili, Brescia, Italy
| | - Marta Pengo
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy; Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Irene Mattioli
- Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Valentina Cantoni
- Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Juergen Dukart
- Institute of Neuroscience and Medicine, Brain & Behaviour (INM-7), Research CentreJülich, Jülich, Germany; Institute of Systems Neuroscience, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Roberto Gasparotti
- Neuroradiology Unit, Department of Medical and Surgical Specialties, University of Brescia, Brescia, Italy
| | | | - Alessandro Padovani
- Neurology, Department of Neurological and Vision Sciences, ASST Spedali Civili, Brescia, Italy; Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Martina Bocchetta
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom; Centre for Cognitive and Clinical Neuroscience, Division of Psychology, Department of Life Sciences, College of Health, Medicine and Life Sciences, Brunel University London, London, United Kingdom
| | - Emily G Todd
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Arabella Bouzigues
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - David M Cash
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom; Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Rhian S Convery
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Lucy L Russell
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Phoebe Foster
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - David L Thomas
- Neuroradiological Academic Unit, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - John C van Swieten
- Department of Neurology and Alzheimer center, Erasmus Medical Center Rotterdam, the Netherlands
| | - Lize C Jiskoot
- Department of Neurology and Alzheimer center, Erasmus Medical Center Rotterdam, the Netherlands
| | - Harro Seelaar
- Department of Neurology and Alzheimer center, Erasmus Medical Center Rotterdam, the Netherlands
| | - Daniela Galimberti
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy; Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Raquel Sanchez-Valle
- Neurology Department, Hospital Clinic, Institut d'Investigacions Biomèdiques, Barcelona, Spain
| | - Robert Laforce
- Clinique Interdisciplinaire de Mémoire, Département des Sciences Neurologiques, CHU de Québec, Faculté de Médecine, Université Laval, Québec, Canada
| | - Fermin Moreno
- Hospital Universitario Donostia, San Sebastian, Spain
| | - Matthis Synofzik
- Division Translational Genomics of Neurodegenerative Diseases, Hertie Institute for Clinical Brain Research (HIH), University of Tübingen, Tübingen, Germany; German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany
| | - Caroline Graff
- Karolinska Institutet, Department NVS, Division of Neurogeriatrics, Stockholm, Sweden; Unit for Hereditray Dementia, Theme Aging, Karolinska University Hospital, Solna, Stockholm, Sweden
| | - Mario Masellis
- Campbell Cognitive Neurology Research Unit, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Maria Carmela Tartaglia
- Toronto Western Hospital, Tanz Centre for Research in Neurodegenerative Disease, Toronto, ON, Canada
| | - James B Rowe
- Department of Clinical Neurosciences and Cambridge University Hospitals NHS Trust and Medical Research Council Cognition and brain Sciences Unit, University of Cambridge, Cambridge, United Kingdom
| | - Kamen A Tsvetanov
- Department of Clinical Neurosciences and Cambridge University Hospitals NHS Trust and Medical Research Council Cognition and brain Sciences Unit, University of Cambridge, Cambridge, United Kingdom
| | - Rik Vandenberghe
- Laboratory for Cognitive Neurology, Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Elizabeth Finger
- Department of Clinical Neurological Sciences, University of Western Ontario, London, ON, Canada
| | - Pietro Tiraboschi
- Fondazione Istituto di Ricovero e Cura a Carattere Scientifico, Istituto Neurologico Carlo Besta, Milan, Italy
| | | | - Isabel Santana
- Neurology Department, Centro Hospitalar e Universitário de Coimbra, Portugal
| | - Chris R Butler
- Department of Clinical Neurology, University of Oxford, Oxford, United Kingdom
| | - Simon Ducharme
- Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada
| | - Alexander Gerhard
- Division of Neuroscience and Experimental Psychology, Wolfson Molecular Imaging Centre, University of Manchester, Manchester, United Kingdom; Departments of Geriatric Medicine and Nuclear Medicine, University of Duisburg-Essen, Germany
| | - Johannes Levin
- Neurologische Klinik und Poliklinik, Ludwig-Maximilians-Universität, Munich, Germany; German Center for Neurodegenerative Diseases (DZNE), Munich, Germany; Munich Cluster of System Neurology, Munich, Germany
| | - Markus Otto
- Department of Neurology, University Hospital Halle, Halle, Germany
| | - Sandro Sorbi
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy; IRCCS Fondazione Don Carlo Gnocchi, Florence, Italy
| | - Isabelle Le Ber
- Sorbonne Université, Paris Brain Institute - Institut du Cerveau - ICM, Inserm U1127, CNRS UMR 7225, AP-HP - Hôpital Pitié-Salpêtrière, Paris, France; Centre de référence des démences rares ou précoces, IM2A, Département de Neurologie, AP-HP - Hôpital Pitié-Salpêtrière, Paris, France; Département de Neurologie, AP-HP - Hôpital Pitié-Salpêtrière, Paris, France; Reference Network for Rare Neurological Diseases (ERN-RND)
| | - Florence Pasquier
- University of Lille, France; Inserm 1172, Lille, France; CHU, CNR-MAJ, Labex Distalz, LiCEND Lille, France
| | - Jonathan D Rohrer
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Barbara Borroni
- Neurology, Department of Neurological and Vision Sciences, ASST Spedali Civili, Brescia, Italy; Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy.
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4
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Kubota M, Kimura Y, Shimojo M, Takado Y, Duarte JMN, Takuwa H, Seki C, Shimada H, Shinotoh H, Takahata K, Kitamura S, Moriguchi S, Tagai K, Obata T, Nakahara J, Tomita Y, Tokunaga M, Maeda J, Kawamura K, Zhang MR, Ichise M, Suhara T, Higuchi M. Dynamic alterations in the central glutamatergic status following food and glucose intake: in vivo multimodal assessments in humans and animal models. J Cereb Blood Flow Metab 2021; 41:2928-2943. [PMID: 34039039 PMCID: PMC8545038 DOI: 10.1177/0271678x211004150] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 02/24/2021] [Accepted: 02/28/2021] [Indexed: 11/17/2022]
Abstract
Fluctuations of neuronal activities in the brain may underlie relatively slow components of neurofunctional alterations, which can be modulated by food intake and related systemic metabolic statuses. Glutamatergic neurotransmission plays a major role in the regulation of excitatory tones in the central nervous system, although just how dietary elements contribute to the tuning of this system remains elusive. Here, we provide the first demonstration by bimodal positron emission tomography (PET) and magnetic resonance spectroscopy (MRS) that metabotropic glutamate receptor subtype 5 (mGluR5) ligand binding and glutamate levels in human brains are dynamically altered in a manner dependent on food intake and consequent changes in plasma glucose levels. The brain-wide modulations of central mGluR5 ligand binding and glutamate levels and profound neuronal activations following systemic glucose administration were further proven by PET, MRS, and intravital two-photon microscopy, respectively, in living rodents. The present findings consistently support the notion that food-associated glucose intake is mechanistically linked to glutamatergic tones in the brain, which are translationally accessible in vivo by bimodal PET and MRS measurements in both clinical and non-clinical settings.
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Affiliation(s)
- Manabu Kubota
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
- Department of Psychiatry, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Yasuyuki Kimura
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
- Department of Clinical and Experimental Neuroimaging, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Obu, Japan
| | - Masafumi Shimojo
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Yuhei Takado
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Joao MN Duarte
- Department of Experimental Medical Science, Faculty of Medicine, Lund University, Lund, Sweden
- Wallenberg Centre for Molecular Medicine, Lund University, Lund, Sweden
| | - Hiroyuki Takuwa
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Chie Seki
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Hitoshi Shimada
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Hitoshi Shinotoh
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Keisuke Takahata
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Soichiro Kitamura
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
- Department of Psychiatry, Nara Medical University, Nara, Japan
| | - Sho Moriguchi
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Kenji Tagai
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Takayuki Obata
- Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Jin Nakahara
- Department of Neurology, Keio University School of Medicine, Tokyo, Japan
| | - Yutaka Tomita
- Department of Neurology, Keio University School of Medicine, Tokyo, Japan
- Tomita Hospital, Aichi, Japan
| | - Masaki Tokunaga
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Jun Maeda
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Kazunori Kawamura
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Ming-Rong Zhang
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Masanori Ichise
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Tetsuya Suhara
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Makoto Higuchi
- Department of Functional Brain Imaging, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
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5
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Bowles KR, Silva MC, Whitney K, Bertucci T, Berlind JE, Lai JD, Garza JC, Boles NC, Mahali S, Strang KH, Marsh JA, Chen C, Pugh DA, Liu Y, Gordon RE, Goderie SK, Chowdhury R, Lotz S, Lane K, Crary JF, Haggarty SJ, Karch CM, Ichida JK, Goate AM, Temple S. ELAVL4, splicing, and glutamatergic dysfunction precede neuron loss in MAPT mutation cerebral organoids. Cell 2021; 184:4547-4563.e17. [PMID: 34314701 PMCID: PMC8635409 DOI: 10.1016/j.cell.2021.07.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 05/06/2021] [Accepted: 06/30/2021] [Indexed: 12/21/2022]
Abstract
Frontotemporal dementia (FTD) because of MAPT mutation causes pathological accumulation of tau and glutamatergic cortical neuronal death by unknown mechanisms. We used human induced pluripotent stem cell (iPSC)-derived cerebral organoids expressing tau-V337M and isogenic corrected controls to discover early alterations because of the mutation that precede neurodegeneration. At 2 months, mutant organoids show upregulated expression of MAPT, glutamatergic signaling pathways, and regulators, including the RNA-binding protein ELAVL4, and increased stress granules. Over the following 4 months, mutant organoids accumulate splicing changes, disruption of autophagy function, and build-up of tau and P-tau-S396. By 6 months, tau-V337M organoids show specific loss of glutamatergic neurons as seen in individuals with FTD. Mutant neurons are susceptible to glutamate toxicity, which can be rescued pharmacologically by the PIKFYVE kinase inhibitor apilimod. Our results demonstrate a sequence of events that precede neurodegeneration, revealing molecular pathways associated with glutamate signaling as potential targets for therapeutic intervention in FTD.
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Affiliation(s)
- Kathryn R Bowles
- Ronald M. Loeb Center for Alzheimer's Disease, Friedman Brain Institute, Departments of Genetics and Genomic Sciences, Neuroscience, and Neurology, Icahn School of Medicine at Mount Sinai (ISMMS), New York, NY 10029, USA
| | - M Catarina Silva
- Chemical Neurobiology Laboratory, Center for Genomic Medicine, Departments of Neurology and Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Kristen Whitney
- Ronald M. Loeb Center for Alzheimer's Disease, Friedman Brain Institute, Departments of Genetics and Genomic Sciences, Neuroscience, and Neurology, Icahn School of Medicine at Mount Sinai (ISMMS), New York, NY 10029, USA; Department of Pathology, Neuropathology Brain Bank and Research Core, ISMMS, New York, NY 10029, USA
| | | | - Joshua E Berlind
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Jesse D Lai
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA; Amgen Research, One Amgen Center Dr., Thousand Oaks, CA 91320, USA
| | - Jacob C Garza
- Chemical Neurobiology Laboratory, Center for Genomic Medicine, Departments of Neurology and Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | | | - Sidhartha Mahali
- Department of Psychiatry, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Kevin H Strang
- Ronald M. Loeb Center for Alzheimer's Disease, Friedman Brain Institute, Departments of Genetics and Genomic Sciences, Neuroscience, and Neurology, Icahn School of Medicine at Mount Sinai (ISMMS), New York, NY 10029, USA; Department of Pathology, Neuropathology Brain Bank and Research Core, ISMMS, New York, NY 10029, USA
| | - Jacob A Marsh
- Department of Psychiatry, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Cynthia Chen
- Department of Psychiatry, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Derian A Pugh
- Ronald M. Loeb Center for Alzheimer's Disease, Friedman Brain Institute, Departments of Genetics and Genomic Sciences, Neuroscience, and Neurology, Icahn School of Medicine at Mount Sinai (ISMMS), New York, NY 10029, USA
| | - Yiyuan Liu
- Ronald M. Loeb Center for Alzheimer's Disease, Friedman Brain Institute, Departments of Genetics and Genomic Sciences, Neuroscience, and Neurology, Icahn School of Medicine at Mount Sinai (ISMMS), New York, NY 10029, USA
| | - Ronald E Gordon
- Department of Pathology, Neuropathology Brain Bank and Research Core, ISMMS, New York, NY 10029, USA
| | | | | | - Steven Lotz
- Neural Stem Cell Institute, Rensselaer, NY 12144, USA
| | - Keith Lane
- Neural Stem Cell Institute, Rensselaer, NY 12144, USA
| | - John F Crary
- Department of Pathology, Neuropathology Brain Bank and Research Core, ISMMS, New York, NY 10029, USA
| | - Stephen J Haggarty
- Chemical Neurobiology Laboratory, Center for Genomic Medicine, Departments of Neurology and Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Celeste M Karch
- Department of Psychiatry, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Justin K Ichida
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Alison M Goate
- Ronald M. Loeb Center for Alzheimer's Disease, Friedman Brain Institute, Departments of Genetics and Genomic Sciences, Neuroscience, and Neurology, Icahn School of Medicine at Mount Sinai (ISMMS), New York, NY 10029, USA.
| | - Sally Temple
- Neural Stem Cell Institute, Rensselaer, NY 12144, USA.
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6
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Rizzi L, Aventurato ÍK, Balthazar MLF. Neuroimaging Research on Dementia in Brazil in the Last Decade: Scientometric Analysis, Challenges, and Peculiarities. Front Neurol 2021; 12:640525. [PMID: 33790850 PMCID: PMC8005640 DOI: 10.3389/fneur.2021.640525] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/18/2021] [Indexed: 12/12/2022] Open
Abstract
The last years have evinced a remarkable growth in neuroimaging studies around the world. All these studies have contributed to a better understanding of the cerebral outcomes of dementia, even in the earliest phases. In low- and middle-income countries, studies involving structural and functional neuroimaging are challenging due to low investments and heterogeneous populations. Outstanding the importance of diagnosing mild cognitive impairment and dementia, the purpose of this paper is to offer an overview of neuroimaging dementia research in Brazil. The review includes a brief scientometric analysis of quantitative information about the development of this field over the past 10 years. Besides, discusses some peculiarities and challenges that have limited neuroimaging dementia research in this big and heterogeneous country of Latin America. We systematically reviewed existing neuroimaging literature with Brazilian authors that presented outcomes related to a dementia syndrome, published from 2010 to 2020. Briefly, the main neuroimaging methods used were morphometrics, followed by fMRI, and DTI. The major diseases analyzed were Alzheimer's disease, mild cognitive impairment, and vascular dementia, respectively. Moreover, research activity in Brazil has been restricted almost entirely to a few centers in the Southeast region, and funding could be the main driver for publications. There was relative stability concerning the number of publications per year, the citation impact has historically been below the world average, and the author's gender inequalities are not relevant in this specific field. Neuroimaging research in Brazil is far from being developed and widespread across the country. Fortunately, increasingly collaborations with foreign partnerships contribute to the impact of Brazil's domestic research. Although the challenges, neuroimaging researches performed in the native population regarding regional peculiarities and adversities are of pivotal importance.
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Affiliation(s)
- Liara Rizzi
- Department of Neurology, University of Campinas (UNICAMP), Campinas, Brazil
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7
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Murley AG, Rouse MA, Jones PS, Ye R, Hezemans FH, O’Callaghan C, Frangou P, Kourtzi Z, Rua C, Carpenter TA, Rodgers CT, Rowe JB. GABA and glutamate deficits from frontotemporal lobar degeneration are associated with disinhibition. Brain 2020; 143:3449-3462. [PMID: 33141154 PMCID: PMC7719029 DOI: 10.1093/brain/awaa305] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 07/11/2020] [Accepted: 07/22/2020] [Indexed: 12/21/2022] Open
Abstract
Behavioural disinhibition is a common feature of the syndromes associated with frontotemporal lobar degeneration (FTLD). It is associated with high morbidity and lacks proven symptomatic treatments. A potential therapeutic strategy is to correct the neurotransmitter deficits associated with FTLD, thereby improving behaviour. Reductions in the neurotransmitters glutamate and GABA correlate with impulsive behaviour in several neuropsychiatric diseases and there is post-mortem evidence of their deficit in FTLD. Here, we tested the hypothesis that prefrontal glutamate and GABA levels are reduced by FTLD in vivo, and that their deficit is associated with impaired response inhibition. Thirty-three participants with a syndrome associated with FTLD (15 patients with behavioural variant frontotemporal dementia and 18 with progressive supranuclear palsy, including both Richardson's syndrome and progressive supranuclear palsy-frontal subtypes) and 20 healthy control subjects were included. Participants undertook ultra-high field (7 T) magnetic resonance spectroscopy and a stop-signal task of response inhibition. We measured glutamate and GABA levels using semi-LASER magnetic resonance spectroscopy in the right inferior frontal gyrus, because of its strong association with response inhibition, and in the primary visual cortex, as a control region. The stop-signal reaction time was calculated using an ex-Gaussian Bayesian model. Participants with frontotemporal dementia and progressive supranuclear palsy had impaired response inhibition, with longer stop-signal reaction times compared with controls. GABA concentration was reduced in patients versus controls in the right inferior frontal gyrus, but not the occipital lobe. There was no group-wise difference in partial volume corrected glutamate concentration between patients and controls. Both GABA and glutamate concentrations in the inferior frontal gyrus correlated inversely with stop-signal reaction time, indicating greater impulsivity in proportion to the loss of each neurotransmitter. We conclude that the glutamatergic and GABAergic deficits in the frontal lobe are potential targets for symptomatic drug treatment of frontotemporal dementia and progressive supranuclear palsy.
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Affiliation(s)
- Alexander G Murley
- Department of Clinical Neurosciences, University of Cambridge, UK
- Cambridge University Hospitals NHS Foundation Trust, UK
| | - Matthew A Rouse
- Department of Clinical Neurosciences, University of Cambridge, UK
| | - P Simon Jones
- Department of Clinical Neurosciences, University of Cambridge, UK
| | - Rong Ye
- Department of Clinical Neurosciences, University of Cambridge, UK
| | - Frank H Hezemans
- Department of Clinical Neurosciences, University of Cambridge, UK
- MRC Cognition and Brain Sciences Unit, University of Cambridge, UK
| | | | | | - Zoe Kourtzi
- Department of Psychology, University of Cambridge, UK
| | - Catarina Rua
- Wolfson Brain Imaging Centre, University of Cambridge, UK
| | | | | | - James B Rowe
- Department of Clinical Neurosciences, University of Cambridge, UK
- Cambridge University Hospitals NHS Foundation Trust, UK
- MRC Cognition and Brain Sciences Unit, University of Cambridge, UK
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8
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Novel PET Biomarkers to Disentangle Molecular Pathways across Age-Related Neurodegenerative Diseases. Cells 2020; 9:cells9122581. [PMID: 33276490 PMCID: PMC7761606 DOI: 10.3390/cells9122581] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/25/2020] [Accepted: 11/28/2020] [Indexed: 12/11/2022] Open
Abstract
There is a need to disentangle the etiological puzzle of age-related neurodegenerative diseases, whose clinical phenotypes arise from known, and as yet unknown, pathways that can act distinctly or in concert. Enhanced sub-phenotyping and the identification of in vivo biomarker-driven signature profiles could improve the stratification of patients into clinical trials and, potentially, help to drive the treatment landscape towards the precision medicine paradigm. The rapidly growing field of neuroimaging offers valuable tools to investigate disease pathophysiology and molecular pathways in humans, with the potential to capture the whole disease course starting from preclinical stages. Positron emission tomography (PET) combines the advantages of a versatile imaging technique with the ability to quantify, to nanomolar sensitivity, molecular targets in vivo. This review will discuss current research and available imaging biomarkers evaluating dysregulation of the main molecular pathways across age-related neurodegenerative diseases. The molecular pathways focused on in this review involve mitochondrial dysfunction and energy dysregulation; neuroinflammation; protein misfolding; aggregation and the concepts of pathobiology, synaptic dysfunction, neurotransmitter dysregulation and dysfunction of the glymphatic system. The use of PET imaging to dissect these molecular pathways and the potential to aid sub-phenotyping will be discussed, with a focus on novel PET biomarkers.
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9
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Treyer V, Gietl AF, Suliman H, Gruber E, Meyer R, Buchmann A, Johayem A, Unschuld PG, Nitsch RM, Buck A, Ametamey SM, Hock C. Reduced uptake of [11C]-ABP688, a PET tracer for metabolic glutamate receptor 5 in hippocampus and amygdala in Alzheimer's dementia. Brain Behav 2020; 10:e01632. [PMID: 32304284 PMCID: PMC7303388 DOI: 10.1002/brb3.1632] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 02/13/2020] [Accepted: 03/10/2020] [Indexed: 12/16/2022] Open
Abstract
INTRODUCTION Metabotropic glutamate receptors play a critical role in the pathogenesis of Alzheimer's disease due to their involvement in processes of memory formation, neuroplasticity, and synaptotoxity. The objective of the current study was to study mGluR5 availability measured by [11 C]-ABP688 (ABP) in patients with clinically diagnosed Alzheimer's dementia (AD). METHODS A bolus-infusion protocol of [11 C]-ABP688 was applied in 9 subjects with AD and 10 cognitively healthy controls (Controls) to derive distribution volume estimates of mGluR5. Furthermore, we also estimated cerebral perfusion by averaging early frame signal of initial ABP bolus injection. RESULTS Subjects with Alzheimer's dementia (mean age: 77.3/SD 5.7) were older than controls (mean age: 68.5/SD: 9.6) and scored lower on the MMSE (22.1/SD2.7 vs. 29.0/SD0.8). There were no overall differences in ABP signal. However, distribution volume ratio (DVR) for ABP was reduced in the bilateral hippocampus (AD: 1.34/SD: 0.40 vs. Control: 1.84/SD:0.31, p = .007) and the bilateral amygdala (AD:1.86/SD:0.26 vs. Control:2.33/SD:0.37 p = .006) in AD patients compared to controls. Estimate of cerebral blood flow was reduced in the bilateral hippocampus in AD (AD:0.75/SD:0.10 vs. Control:0.86/SD:0.09 p = .02). CONCLUSION Our findings demonstrate reduced mGluR5 binding in the hippocampus and amygdala in Alzheimer's dementia. Whether this is due to synaptic loss and/or consecutive reduction of potential binding sites or reflects disease inherent mechanisms remains to be elucidated in future studies.
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Affiliation(s)
- Valerie Treyer
- Institute for Regenerative Medicine (IREM), University of Zurich, Schlieren, Switzerland.,Department of Nuclear Medicine, University Hospital of Zurich, Zurich, Switzerland
| | - Anton F Gietl
- Institute for Regenerative Medicine (IREM), University of Zurich, Schlieren, Switzerland
| | - Husam Suliman
- Hospital for Psychogeriatric Medicine, University of Zurich, Zurich, Switzerland
| | - Esmeralda Gruber
- Institute for Regenerative Medicine (IREM), University of Zurich, Schlieren, Switzerland
| | - Rafael Meyer
- Institute for Regenerative Medicine (IREM), University of Zurich, Schlieren, Switzerland
| | - Andreas Buchmann
- Institute for Regenerative Medicine (IREM), University of Zurich, Schlieren, Switzerland
| | - Anass Johayem
- Department of Nuclear Medicine, University Hospital of Zurich, Zurich, Switzerland
| | - Paul G Unschuld
- Hospital for Psychogeriatric Medicine, University of Zurich, Zurich, Switzerland
| | - Roger M Nitsch
- Institute for Regenerative Medicine (IREM), University of Zurich, Schlieren, Switzerland.,Neurimmune, Schlieren, Switzerland
| | - Alfred Buck
- Department of Nuclear Medicine, University Hospital of Zurich, Zurich, Switzerland
| | - Simon M Ametamey
- Institute of Radiopharmaceutical Sciences, ETH Zurich, Zurich, Switzerland
| | - Christoph Hock
- Institute for Regenerative Medicine (IREM), University of Zurich, Schlieren, Switzerland.,Neurimmune, Schlieren, Switzerland
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10
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Selective Disruption of Inhibitory Synapses Leading to Neuronal Hyperexcitability at an Early Stage of Tau Pathogenesis in a Mouse Model. J Neurosci 2020; 40:3491-3501. [PMID: 32265258 DOI: 10.1523/jneurosci.2880-19.2020] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 03/12/2020] [Accepted: 03/13/2020] [Indexed: 01/01/2023] Open
Abstract
Synaptic dysfunction provoking dysregulated cortical neural circuits is currently hypothesized as a key pathophysiological process underlying clinical manifestations in Alzheimer's disease and related neurodegenerative tauopathies. Here, we conducted PET along with postmortem assays to investigate time course changes of excitatory and inhibitory synaptic constituents in an rTg4510 mouse model of tauopathy, which develops tau pathologies leading to noticeable brain atrophy at 5-6 months of age. Both male and female mice were analyzed in this study. We observed that radiosignals derived from [11C]flumazenil, a tracer for benzodiazepine receptor, in rTg4510 mice were significantly lower than the levels in nontransgenic littermates at 2-3 months of age. In contrast, retentions of (E)-[11C]ABP688, a tracer for mGluR5, were unaltered relative to controls at 2 months of age but then gradually declined with aging in parallel with progressive brain atrophy. Biochemical and immunohistochemical assessment of postmortem brain tissues demonstrated that inhibitory, but not excitatory, synaptic constituents selectively diminished without overt loss of somas of GABAergic interneurons in the neocortex and hippocampus of rTg4510 mice at 2 months of age, which was concurrent with enhanced immunoreactivity of cFos, a well-characterized immediate early gene, suggesting that impaired inhibitory neurotransmission may cause hyperexcitability of cortical circuits. Our findings indicate that tau-induced disruption of the inhibitory synapse may be a critical trigger of progressive neurodegeneration, resulting in massive neuronal loss, and PET assessments of inhibitory versus excitatory synapses potentially offer in vivo indices for hyperexcitability and excitotoxicity early in the etiologic pathway of neurodegenerative tauopathies.SIGNIFICANCE STATEMENT In this study, we examined the in vivo status of excitatory and inhibitory synapses in the brain of the rTg4510 tauopathy mouse model by PET imaging with (E)-[11C]ABP688 and [11C]flumazenil, respectively. We identified inhibitory synapse as being significantly dysregulated before brain atrophy at 2 months of age, while excitatory synapse stayed relatively intact at this stage. In line with this observation, postmortem assessment of brain tissues demonstrated selective attenuation of inhibitory synaptic constituents accompanied by the upregulation of cFos before the formation of tau pathology in the forebrain at young ages. Our findings indicate that selective degeneration of inhibitory synapse with hyperexcitability in the cortical circuit constitutes the critical early pathophysiology of tauopathy.
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11
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Azam S, Haque ME, Jakaria M, Jo SH, Kim IS, Choi DK. G-Protein-Coupled Receptors in CNS: A Potential Therapeutic Target for Intervention in Neurodegenerative Disorders and Associated Cognitive Deficits. Cells 2020; 9:cells9020506. [PMID: 32102186 PMCID: PMC7072884 DOI: 10.3390/cells9020506] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 02/15/2020] [Accepted: 02/18/2020] [Indexed: 12/17/2022] Open
Abstract
Neurodegenerative diseases are a large group of neurological disorders with diverse etiological and pathological phenomena. However, current therapeutics rely mostly on symptomatic relief while failing to target the underlying disease pathobiology. G-protein-coupled receptors (GPCRs) are one of the most frequently targeted receptors for developing novel therapeutics for central nervous system (CNS) disorders. Many currently available antipsychotic therapeutics also act as either antagonists or agonists of different GPCRs. Therefore, GPCR-based drug development is spreading widely to regulate neurodegeneration and associated cognitive deficits through the modulation of canonical and noncanonical signals. Here, GPCRs’ role in the pathophysiology of different neurodegenerative disease progressions and cognitive deficits has been highlighted, and an emphasis has been placed on the current pharmacological developments with GPCRs to provide an insight into a potential therapeutic target in the treatment of neurodegeneration.
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Affiliation(s)
- Shofiul Azam
- Department of Applied Life Science & Integrated Bioscience, Graduate School, Konkuk University, Chungju 27478, Korea; (S.A.); (M.E.H.); (M.J.); (S.-H.J.)
| | - Md. Ezazul Haque
- Department of Applied Life Science & Integrated Bioscience, Graduate School, Konkuk University, Chungju 27478, Korea; (S.A.); (M.E.H.); (M.J.); (S.-H.J.)
| | - Md. Jakaria
- Department of Applied Life Science & Integrated Bioscience, Graduate School, Konkuk University, Chungju 27478, Korea; (S.A.); (M.E.H.); (M.J.); (S.-H.J.)
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Song-Hee Jo
- Department of Applied Life Science & Integrated Bioscience, Graduate School, Konkuk University, Chungju 27478, Korea; (S.A.); (M.E.H.); (M.J.); (S.-H.J.)
| | - In-Su Kim
- Department of Integrated Bioscience & Biotechnology, College of Biomedical and Health Science, and Research Institute of Inflammatory Disease (RID), Konkuk University, Chungju 27478, Korea
- Correspondence: (I.-S.K.); (D.-K.C.); Tel.: +82-010-3876-4773 (I.-S.K.); +82-43-840-3610 (D.-K.C.); Fax: +82-43-840-3872 (D.-K.C.)
| | - Dong-Kug Choi
- Department of Applied Life Science & Integrated Bioscience, Graduate School, Konkuk University, Chungju 27478, Korea; (S.A.); (M.E.H.); (M.J.); (S.-H.J.)
- Department of Integrated Bioscience & Biotechnology, College of Biomedical and Health Science, and Research Institute of Inflammatory Disease (RID), Konkuk University, Chungju 27478, Korea
- Correspondence: (I.-S.K.); (D.-K.C.); Tel.: +82-010-3876-4773 (I.-S.K.); +82-43-840-3610 (D.-K.C.); Fax: +82-43-840-3872 (D.-K.C.)
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12
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Translating preclinical findings in clinically relevant new antipsychotic targets: focus on the glutamatergic postsynaptic density. Implications for treatment resistant schizophrenia. Neurosci Biobehav Rev 2019; 107:795-827. [DOI: 10.1016/j.neubiorev.2019.08.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 07/20/2019] [Accepted: 08/22/2019] [Indexed: 02/07/2023]
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13
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Beaurain M, Salabert AS, Ribeiro MJ, Arlicot N, Damier P, Le Jeune F, Demonet JF, Payoux P. Innovative Molecular Imaging for Clinical Research, Therapeutic Stratification, and Nosography in Neuroscience. Front Med (Lausanne) 2019; 6:268. [PMID: 31828073 PMCID: PMC6890558 DOI: 10.3389/fmed.2019.00268] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 11/01/2019] [Indexed: 01/06/2023] Open
Abstract
Over the past few decades, several radiotracers have been developed for neuroimaging applications, especially in PET. Because of their low steric hindrance, PET radionuclides can be used to label molecules that are small enough to cross the blood brain barrier, without modifying their biological properties. As the use of 11C is limited by its short physical half-life (20 min), there has been an increasing focus on developing tracers labeled with 18F for clinical use. The first such tracers allowed cerebral blood flow and glucose metabolism to be measured, and the development of molecular imaging has since enabled to focus more closely on specific targets such as receptors, neurotransmitter transporters, and other proteins. Hence, PET and SPECT biomarkers have become indispensable for innovative clinical research. Currently, the treatment options for a number of pathologies, notably neurodegenerative diseases, remain only supportive and symptomatic. Treatments that slow down or reverse disease progression are therefore the subject of numerous studies, in which molecular imaging is proving to be a powerful tool. PET and SPECT biomarkers already make it possible to diagnose several neurological diseases in vivo and at preclinical stages, yielding topographic, and quantitative data about the target. As a result, they can be used for assessing patients' eligibility for new treatments, or for treatment follow-up. The aim of the present review was to map major innovative radiotracers used in neuroscience, and explain their contribution to clinical research. We categorized them according to their target: dopaminergic, cholinergic or serotoninergic systems, β-amyloid plaques, tau protein, neuroinflammation, glutamate or GABA receptors, or α-synuclein. Most neurological disorders, and indeed mental disorders, involve the dysfunction of one or more of these targets. Combinations of molecular imaging biomarkers can afford us a better understanding of the mechanisms underlying disease development over time, and contribute to early detection/screening, diagnosis, therapy delivery/monitoring, and treatment follow-up in both research and clinical settings.
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Affiliation(s)
- Marie Beaurain
- CHU de Toulouse, Toulouse, France.,ToNIC, Toulouse NeuroImaging Center, Inserm U1214, Toulouse, France
| | - Anne-Sophie Salabert
- CHU de Toulouse, Toulouse, France.,ToNIC, Toulouse NeuroImaging Center, Inserm U1214, Toulouse, France
| | - Maria Joao Ribeiro
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France.,Inserm CIC 1415, University Hospital, Tours, France.,CHRU Tours, Tours, France
| | - Nicolas Arlicot
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France.,Inserm CIC 1415, University Hospital, Tours, France.,CHRU Tours, Tours, France
| | - Philippe Damier
- Inserm U913, Neurology Department, University Hospital, Nantes, France
| | | | - Jean-François Demonet
- Leenards Memory Centre, Department of Clinical Neuroscience, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Pierre Payoux
- CHU de Toulouse, Toulouse, France.,ToNIC, Toulouse NeuroImaging Center, Inserm U1214, Toulouse, France
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14
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Palese F, Bonomi E, Nuzzo T, Benussi A, Mellone M, Zianni E, Cisani F, Casamassa A, Alberici A, Scheggia D, Padovani A, Marcello E, Di Luca M, Pittaluga A, Usiello A, Borroni B, Gardoni F. Anti-GluA3 antibodies in frontotemporal dementia: effects on glutamatergic neurotransmission and synaptic failure. Neurobiol Aging 2019; 86:143-155. [PMID: 31784278 DOI: 10.1016/j.neurobiolaging.2019.10.015] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 10/10/2019] [Accepted: 10/26/2019] [Indexed: 11/19/2022]
Abstract
Despite the great effort of the scientific community in the field, the pathogenesis of frontotemporal dementia (FTD) remains elusive. Recently, a role for autoimmunity and altered glutamatergic neurotransmission in triggering disease onset has been put forward. We reported the presence of autoantibodies recognizing the GluA3 subunit of α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptors in about 25% of FTD cases. In this study, we evaluated the mechanisms involved in anti-GluA3 autoimmunity, through molecular/neurochemical analyses conducted on patients' brain specimens with frontotemporal lobar degeneration-tau neuropathology. We then corroborated these results in vivo in FTD patients with transcranial magnetic stimulation and glutamate, D-serine, and L-serine dosages in the cerebrospinal fluid and serum. We observed that GluA3 autoantibodies affect glutamatergic neurotransmission, decreasing glutamate release and altering GluA3-containing α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor levels. These alterations were accompanied by changes of scaffolding proteins involved in receptor synaptic retention/internalization. The above results were confirmed by transcranial magnetic stimulation, suggesting a significant impairment of indirect measures of glutamatergic neurotransmission in FTD patients compared with controls, with further add-on harmful effect in those FTD patients with anti-GluA3 antibodies. Finally, FTD patients showed a significant increase of glutamate, D-serine, and L-serine levels in the cerebrospinal fluid.
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Affiliation(s)
- Francesca Palese
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Elisa Bonomi
- Department of Clinical and Experimental Sciences, Neurology Unit, Centre for Neurodegenerative Disorders, University of Brescia, Brescia, Italy
| | - Tommaso Nuzzo
- Translational Neuroscience Unit, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | - Alberto Benussi
- Department of Clinical and Experimental Sciences, Neurology Unit, Centre for Neurodegenerative Disorders, University of Brescia, Brescia, Italy
| | - Manuela Mellone
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Elisa Zianni
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Francesca Cisani
- Department of Pharmacy, DiFAR, School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy
| | - Alessia Casamassa
- Translational Neuroscience Unit, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | - Antonella Alberici
- Department of Clinical and Experimental Sciences, Neurology Unit, Centre for Neurodegenerative Disorders, University of Brescia, Brescia, Italy
| | - Diego Scheggia
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Alessandro Padovani
- Department of Clinical and Experimental Sciences, Neurology Unit, Centre for Neurodegenerative Disorders, University of Brescia, Brescia, Italy
| | - Elena Marcello
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Monica Di Luca
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Anna Pittaluga
- Department of Pharmacy, DiFAR, School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy
| | - Alessandro Usiello
- Translational Neuroscience Unit, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy; Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania Luigi Vanvitelli, Caserta, Italy
| | - Barbara Borroni
- Department of Clinical and Experimental Sciences, Neurology Unit, Centre for Neurodegenerative Disorders, University of Brescia, Brescia, Italy
| | - Fabrizio Gardoni
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy.
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15
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Gauthier S, Ng KP, Pascoal TA, Zhang H, Rosa-Neto P. Targeting Alzheimer's Disease at the Right Time and the Right Place: Validation of a Personalized Approach to Diagnosis and Treatment. J Alzheimers Dis 2019; 64:S23-S31. [PMID: 29504543 PMCID: PMC6004905 DOI: 10.3233/jad-179924] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Cautious optimism is appropriate for a near future (five years) time frame for a number of drugs acting on the different pathophysiological components of Alzheimer’s disease (amyloid deposition, tau hyperphosphorylation, neuroinflammation, vascular changes, to name the most important known so far). Since the relative weight of these components will be different between individuals and will even change over time for each individual, a ‘one drug fit for all’ approach is no longer defensible. Precision medicine using biomarkers in the diagnosis and treatment of Alzheimer’s disease is the new strategy.
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Affiliation(s)
- Serge Gauthier
- McGill Center for Studies in Aging, Douglas Mental Health Research Institute, Montreal, Canada
| | - Kok Pin Ng
- Department of Neurology, National Neuroscience Institute, Singapore
| | - Tharick A Pascoal
- McGill Center for Studies in Aging, Douglas Mental Health Research Institute, Montreal, Canada
| | - Hua Zhang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Pedro Rosa-Neto
- McGill Center for Studies in Aging, Douglas Mental Health Research Institute, Montreal, Canada
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16
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Benussi A, Alberici A, Buratti E, Ghidoni R, Gardoni F, Di Luca M, Padovani A, Borroni B. Toward a Glutamate Hypothesis of Frontotemporal Dementia. Front Neurosci 2019; 13:304. [PMID: 30983965 PMCID: PMC6449454 DOI: 10.3389/fnins.2019.00304] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 03/18/2019] [Indexed: 12/12/2022] Open
Abstract
Frontotemporal dementia (FTD) is a heterogenous neurodegenerative disorder, characterized by diverse clinical presentations, neuropathological characteristics and underlying genetic causes. Emerging evidence has shown that FTD is characterized by a series of changes in several neurotransmitter systems, including serotonin, dopamine, GABA and, above all, glutamate. Indeed, several studies have now provided preclinical and clinical evidence that glutamate is key in the pathogenesis of FTD. Animal models of FTD have shown a selective hypofunction in N-methyl D-aspartate (NMDA) and α-amino-3-hydroxyl-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, while in patients, glutamatergic pyramidal neurons are depleted in several areas, including the frontal and temporal cortices. Recently, a selective involvement of the AMPA GluA3 subunit has been observed in patients with autoimmune anti-GluA3 antibodies, which accounted for nearly 25% of FTD patients, leading to a decrease of the GluA3 subunit synaptic localization of the AMPA receptor and loss of dendritic spines. Other in vivo evidence of the involvement of the glutamatergic system in FTD derives from non-invasive brain stimulation studies using transcranial magnetic stimulation, in which specific stimulation protocols have indirectly identified a selective and prominent impairment in glutamatergic circuits in patients with both sporadic and genetic FTD. In view of limited disease modifying therapies to slow or revert disease progression in FTD, an important approach could consist in targeting the neurotransmitter deficits, similarly to what has been achieved in Parkinson’s disease with dopaminergic therapy or Alzheimer’s disease with cholinergic therapy. In this review, we summarize the current evidence concerning the involvement of the glutamatergic system in FTD, suggesting the development of new therapeutic strategies.
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Affiliation(s)
- Alberto Benussi
- Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Antonella Alberici
- Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology, ICGEB, Trieste, Italy
| | - Roberta Ghidoni
- IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Fabrizio Gardoni
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Monica Di Luca
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Alessandro Padovani
- Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Barbara Borroni
- Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
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17
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Xu Y, Li Z. Imaging metabotropic glutamate receptor system: Application of positron emission tomography technology in drug development. Med Res Rev 2019; 39:1892-1922. [DOI: 10.1002/med.21566] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 01/18/2019] [Accepted: 01/24/2019] [Indexed: 12/17/2022]
Affiliation(s)
- Youwen Xu
- Independent Consultant and Contractor, Radiopharmaceutical Development, Validation and Bio-Application; Philadelphia Pennsylvania
| | - Zizhong Li
- Pharmaceutical Research and Development, SOFIE Biosciences; Somerset New Jersey
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18
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Molecular imaging in dementia: Past, present, and future. Alzheimers Dement 2018; 14:1522-1552. [DOI: 10.1016/j.jalz.2018.06.2855] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 06/02/2018] [Accepted: 06/03/2018] [Indexed: 12/14/2022]
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Murley AG, Rowe JB. Neurotransmitter deficits from frontotemporal lobar degeneration. Brain 2018; 141:1263-1285. [PMID: 29373632 PMCID: PMC5917782 DOI: 10.1093/brain/awx327] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 09/05/2017] [Accepted: 10/03/2017] [Indexed: 12/11/2022] Open
Abstract
Frontotemporal lobar degeneration causes a spectrum of complex degenerative disorders including frontotemporal dementia, progressive supranuclear palsy and corticobasal syndrome, each of which is associated with changes in the principal neurotransmitter systems. We review the evidence for these neurochemical changes and propose that they contribute to symptomatology of frontotemporal lobar degeneration, over and above neuronal loss and atrophy. Despite the development of disease-modifying therapies, aiming to slow neuropathological progression, it remains important to advance symptomatic treatments to reduce the disease burden and improve patients' and carers' quality of life. We propose that targeting the selective deficiencies in neurotransmitter systems, including dopamine, noradrenaline, serotonin, acetylcholine, glutamate and gamma-aminobutyric acid is an important strategy towards this goal. We summarize the current evidence-base for pharmacological treatments and suggest strategies to improve the development of new, effective pharmacological treatments.
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Affiliation(s)
- Alexander G Murley
- Department of Clinical Neurosciences, University of Cambridge, Herchel Smith Building, Robinson Way, Cambridge, CB2 0SZ, UK
| | - James B Rowe
- Department of Clinical Neurosciences, University of Cambridge, Herchel Smith Building, Robinson Way, Cambridge, CB2 0SZ, UK
- MRC Cognition and Brain Sciences Unit, University of Cambridge, 15 Chaucer Road, Cambridge, CB2 7EF, UK
- Behavioural and Clinical Neurosciences Institute, University of Cambridge, Sir William Hardy Building, Downing Street, Cambridge, CB2 3EB, UK
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Abstract
Single-photon emission computed tomography (SPECT) and positron emission tomography (PET) with different radiotracers enable regional evaluation of blood flow and glucose metabolism, of receptors and transporters of several molecules, and of abnormal deposition of peptides and proteins in the brain. The cerebellum has been used as a reference region for different radiotracers in several disease conditions. Whole-brain voxel-wise analysis is not affected by a priori knowledge bias and should be preferred. SPECT and PET have contributed to establishing the cerebellum role in motion, cognition, and emotion control in physiologic and pathophysiologic conditions. The basic abnormal imaging findings include decreased or increased uptake of flow or metabolism tracers in the cerebellum alone or as part of a network. Decreased uptake is generally observed in primary structural damage of the cerebellum, but can also represent a distant effect of cerebral damage (crossed diaschisis). Increased uptake can be observed in Freidreich ataxia, inflammatory or immune-mediated diseases of the cerebellum, and in status epilepticus. The possibility is also recognized that primary structural damage of the cerebellum might determine distance effects on other brain structures (reversed diaschisis). So far, SPECT and PET have been predominantly used in clinical studies to investigate cerebellar changes in neurologic and psychiatric diseases and in connection with pharmacologic, transcranial magnetic stimulation, deep-brain stimulation, or surgical treatments.
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Huang Y, Todd N, Thathiah A. The role of GPCRs in neurodegenerative diseases: avenues for therapeutic intervention. Curr Opin Pharmacol 2017; 32:96-110. [DOI: 10.1016/j.coph.2017.02.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 02/08/2017] [Accepted: 02/09/2017] [Indexed: 12/20/2022]
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22
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Jolly D, Hopewell R, Kovacevic M, Li QY, Soucy JP, Kostikov A. Development of "[ 11C]kits" for a fast, efficient and reliable production of carbon-11 labeled radiopharmaceuticals for Positron Emission Tomography. Appl Radiat Isot 2016; 121:76-81. [PMID: 28038410 DOI: 10.1016/j.apradiso.2016.11.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 11/11/2016] [Accepted: 11/25/2016] [Indexed: 10/20/2022]
Abstract
Translation of carbon-11 labeled PET tracers to clinical settings is currently impeded by the technical difficulties associated with [11C]CO2 conversion into the highly reactive methylating agents [11C]CH3I and [11C]CH3OTf using automated modules relying on stationary valves. Here we describe development of the first in its kind "[11C]kit" for production of carbon-11 radiotracer using disposable manifolds. This method proved to be very reliable and allows for consecutive production of PET tracers with minimal intervals between the syntheses.
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Affiliation(s)
- Dean Jolly
- Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC, Canada H3A2B4
| | - Robert Hopewell
- Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC, Canada H3A2B4
| | - Miriam Kovacevic
- Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC, Canada H3A2B4
| | - Qian Ying Li
- Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC, Canada H3A2B4
| | - Jean-Paul Soucy
- Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC, Canada H3A2B4; Concordia-PERFORM Centre, Concordia University, Montreal, Canada
| | - Alexey Kostikov
- Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC, Canada H3A2B4
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23
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Metabotropic glutamate receptor 5 – a promising target in drug development and neuroimaging. Eur J Nucl Med Mol Imaging 2016; 43:1151-70. [DOI: 10.1007/s00259-015-3301-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Accepted: 12/22/2015] [Indexed: 10/22/2022]
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24
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DeLorenzo C, Sovago J, Gardus J, Xu J, Yang J, Behrje R, Kumar JSD, Devanand DP, Pelton GH, Mathis CA, Mason NS, Gomez-Mancilla B, Aizenstein H, Mann JJ, Parsey RV. Characterization of brain mGluR5 binding in a pilot study of late-life major depressive disorder using positron emission tomography and [¹¹C]ABP688. Transl Psychiatry 2015; 5:e693. [PMID: 26645628 PMCID: PMC5068588 DOI: 10.1038/tp.2015.189] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 10/05/2015] [Accepted: 10/26/2015] [Indexed: 01/06/2023] Open
Abstract
The metabotropic glutamate receptor subtype 5 (mGluR5) has been implicated in the pathophysiology of mood and anxiety disorders and is a potential treatment target in major depressive disorder (MDD). This study compared brain mGluR5 binding in elderly patients suffering from MDD with that in elderly healthy volunteers using positron emission tomography (PET) and [(11)C]ABP688. Twenty elderly (mean age: 63.0 ± 6.3) subjects with MDD and twenty-two healthy volunteers in the same age range (mean age: 66.4 ± 7.3) were examined with PET after a single bolus injection of [(11)C]ABP688, with many receiving arterial sampling. PET images were analyzed on a region of interest and a voxel level to compare mGluR5 binding in the brain between the two groups. Differences in [(11)C]ABP688 binding between patients with early- and late-onset depression were also assessed. In contrast to a previously published report in a younger cohort, no significant difference in [(11)C]ABP688 binding was observed between elderly subjects with MDD and healthy volunteers. [(11)C]ABP688 binding was also similar between subgroups with early- or late-onset depression. We believe this is the first study to examine mGluR5 expression in depression in the elderly. Although future work is required, results suggest potential differences in the pathophysiology of elderly depression versus depression earlier in life.
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Affiliation(s)
- C DeLorenzo
- Department of Psychiatry, Columbia University, New York, NY, USA,Department of Psychiatry, Stony Brook University, Stony Brook, NY, USA,Department of Psychiatry, Stony Brook University, HSC-T-10, Room 40D, Stony Brook, NY 11794, USA. E-mail:
| | - J Sovago
- Novartis Institute for BioMedical Research, Novartis Pharma AG, Basel, Switzerland
| | - J Gardus
- Department of Psychiatry, Stony Brook University, Stony Brook, NY, USA
| | - J Xu
- Department of Applied Mathematics and Statistics, Stony Brook University, Stony Brook, NY, USA
| | - J Yang
- Department of Preventive Medicine, Stony Brook University, Stony Brook, NY, USA
| | - R Behrje
- Novartis Pharmaceuticals Corporations, East Hanover, NJ, USA
| | - J S D Kumar
- Department of Psychiatry, Columbia University, New York, NY, USA
| | - D P Devanand
- Department of Psychiatry, Columbia University, New York, NY, USA
| | - G H Pelton
- Department of Psychiatry, Columbia University, New York, NY, USA
| | - C A Mathis
- Department of Radiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - N S Mason
- Department of Radiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - B Gomez-Mancilla
- Novartis Institute for BioMedical Research, Novartis Pharma AG, Basel, Switzerland
| | - H Aizenstein
- Department of Radiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - J J Mann
- Department of Psychiatry, Columbia University, New York, NY, USA
| | - R V Parsey
- Department of Psychiatry, Stony Brook University, Stony Brook, NY, USA
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25
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Characterization of age/sex and the regional distribution of mGluR5 availability in the healthy human brain measured by high-resolution [11C]ABP688 PET. Eur J Nucl Med Mol Imaging 2015; 43:152-162. [DOI: 10.1007/s00259-015-3167-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Accepted: 08/05/2015] [Indexed: 12/12/2022]
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