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Juvenal G, Higa GSV, Bonfim Marques L, Tessari Zampieri T, Costa Viana FJ, Britto LR, Tang Y, Illes P, di Virgilio F, Ulrich H, de Pasquale R. Regulation of GABAergic neurotransmission by purinergic receptors in brain physiology and disease. Purinergic Signal 2024:10.1007/s11302-024-10034-x. [PMID: 39046648 DOI: 10.1007/s11302-024-10034-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 06/19/2024] [Indexed: 07/25/2024] Open
Abstract
Purinergic receptors regulate the processing of neural information in the hippocampus and cerebral cortex, structures related to cognitive functions. These receptors are activated when astrocytic and neuronal populations release adenosine triphosphate (ATP) in an autocrine and paracrine manner, following sustained patterns of neuronal activity. The modulation by these receptors of GABAergic transmission has only recently been studied. Through their ramifications, astrocytes and GABAergic interneurons reach large groups of excitatory pyramidal neurons. Their inhibitory effect establishes different synchronization patterns that determine gamma frequency rhythms, which characterize neural activities related to cognitive processes. During early life, GABAergic-mediated synchronization of excitatory signals directs the experience-driven maturation of cognitive development, and dysfunctions concerning this process have been associated with neurological and neuropsychiatric diseases. Purinergic receptors timely modulate GABAergic control over ongoing neural activity and deeply affect neural processing in the hippocampal and neocortical circuitry. Stimulation of A2 receptors increases GABA release from presynaptic terminals, leading to a considerable reduction in neuronal firing of pyramidal neurons. A1 receptors inhibit GABAergic activity but only act in the early postnatal period when GABA produces excitatory signals. P2X and P2Y receptors expressed in pyramidal neurons reduce the inhibitory tone by blocking GABAA receptors. Finally, P2Y receptor activation elicits depolarization of GABAergic neurons and increases GABA release, thus favoring the emergence of gamma oscillations. The present review provides an overall picture of purinergic influence on GABAergic transmission and its consequences on neural processing, extending the discussion to receptor subtypes and their involvement in the onset of brain disorders, including epilepsy and Alzheimer's disease.
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Affiliation(s)
- Guilherme Juvenal
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, SP, Brazil
| | - Guilherme Shigueto Vilar Higa
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, SP, Brazil
- Department of Biophysics and Physiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Lucas Bonfim Marques
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, SP, Brazil
| | - Thais Tessari Zampieri
- Department of Biophysics and Physiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Felipe José Costa Viana
- Department of Biophysics and Physiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Luiz R Britto
- Department of Biophysics and Physiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Yong Tang
- International Joint Research Centre On Purinergic Signalling, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
- School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
| | - Peter Illes
- International Joint Research Centre On Purinergic Signalling, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
- School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
- Rudolf Boehm Institute for Pharmacology and Toxicology, University of Leipzig, 04107, Leipzig, Germany
| | | | - Henning Ulrich
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, SP, Brazil.
- International Joint Research Centre On Purinergic Signalling, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China.
| | - Roberto de Pasquale
- Department of Biophysics and Physiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.
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2
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Singer P, Yee BK. Inhibition of astrocytic glycine transporter-1: friend or foe for ameliorating NMDA receptor hypofunction? Front Cell Neurosci 2024; 18:1389718. [PMID: 38854433 PMCID: PMC11158624 DOI: 10.3389/fncel.2024.1389718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 05/09/2024] [Indexed: 06/11/2024] Open
Affiliation(s)
- Philipp Singer
- Roche Diagnostics International AG, Rotkreuz, Switzerland
| | - Benjamin K. Yee
- Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
- Mental Health Research Centre, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
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3
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Yamamoto K, Kosukegawa S, Kobayashi M. P2X receptor- and postsynaptic NMDA receptor-mediated long-lasting facilitation of inhibitory synapses in the rat insular cortex. Neuropharmacology 2024; 245:109817. [PMID: 38104767 DOI: 10.1016/j.neuropharm.2023.109817] [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: 04/23/2023] [Revised: 10/28/2023] [Accepted: 12/14/2023] [Indexed: 12/19/2023]
Abstract
Adenosine triphosphate (ATP) changes the efficacy of synaptic transmission. Despite recent progress in terms of the roles of purinergic receptors in cerebrocortical excitatory synaptic transmission, their contribution to inhibitory synaptic transmission is unknown. To elucidate the effects of α,β-methylene ATP (αβ-mATP), a selective agonist of P2X receptors (P2XRs), on inhibitory synaptic transmission in the insular cortex (IC), we performed whole-cell patch-clamp recording from IC pyramidal neurons (PNs) and fast-spiking neurons (FSNs) in either sex of VGAT-Venus transgenic rats. αβ-mATP increased the amplitude of miniature IPSCs (mIPSCs) under conditions in which NMDA receptors (NMDARs) are recruitable. αβ-mATP-induced facilitation of mIPSCs was sustained even after the washout of αβ-mATP, which was blocked by preincubation with fluorocitrate. The preapplication of NF023 (a P2X1 receptor antagonist) or AF-353 (a P2X3 receptor antagonist) blocked αβ-mATP-induced mIPSC facilitation. Intracellular application of the NMDAR antagonist MK801 blocked the facilitation. d-serine, which is an intrinsic agonist of NMDARs, mimicked αβ-mATP-induced mIPSC facilitation. The intracellular application of BAPTA a Ca2+ chelator, or the bath application of KN-62, a CaMKII inhibitor, blocked αβ-mATP-induced mIPSC facilitation, thus indicating that mIPSC facilitation by αβ-mATP required postsynaptic [Ca2+]i elevation through NMDAR activation. Paired whole-cell patch-clamp recordings from FSNs and PNs demonstrated that αβ-mATP increased the amplitude of unitary IPSCs without changing the paired-pulse ratio. These results suggest that αβ-mATP-induced IPSC facilitation is mediated by postsynaptic NMDAR activations through d-serine released from astrocytes. Subsequent [Ca2+]i increase and postsynaptic CaMKII activation may release retrograde messengers that upregulate GABA release from presynaptic inhibitory neurons, including FSNs. (250/250 words).
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Affiliation(s)
- Kiyofumi Yamamoto
- Department of Pharmacology, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan; Division of Oral and Craniomaxillofacial Research, Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Satoshi Kosukegawa
- Department of Pharmacology, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan; Department of Orthodontics, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Masayuki Kobayashi
- Department of Pharmacology, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan; Division of Oral and Craniomaxillofacial Research, Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan.
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4
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Arribas-Carreira L, Castro M, García F, Navarrete R, Bravo-Alonso I, Zafra F, Ugarte M, Richard E, Pérez B, Rodríguez-Pombo P. Metabolic Rewiring and Altered Glial Differentiation in an iPSC-Derived Astrocyte Model Derived from a Nonketotic Hyperglycinemia Patient. Int J Mol Sci 2024; 25:2814. [PMID: 38474060 DOI: 10.3390/ijms25052814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 02/14/2024] [Accepted: 02/26/2024] [Indexed: 03/14/2024] Open
Abstract
The pathophysiology of nonketotic hyperglycinemia (NKH), a rare neuro-metabolic disorder associated with severe brain malformations and life-threatening neurological manifestations, remains incompletely understood. Therefore, a valid human neural model is essential. We aimed to investigate the impact of GLDC gene variants, which cause NKH, on cellular fitness during the differentiation process of human induced pluripotent stem cells (iPSCs) into iPSC-derived astrocytes and to identify sustainable mechanisms capable of overcoming GLDC deficiency. We developed the GLDC27-FiPS4F-1 line and performed metabolomic, mRNA abundance, and protein analyses. This study showed that although GLDC27-FiPS4F-1 maintained the parental genetic profile, it underwent a metabolic switch to an altered serine-glycine-one-carbon metabolism with a coordinated cell growth and cell cycle proliferation response. We then differentiated the iPSCs into neural progenitor cells (NPCs) and astrocyte-lineage cells. Our analysis showed that GLDC-deficient NPCs had shifted towards a more heterogeneous astrocyte lineage with increased expression of the radial glial markers GFAP and GLAST and the neuronal markers MAP2 and NeuN. In addition, we detected changes in other genes related to serine and glycine metabolism and transport, all consistent with the need to maintain glycine at physiological levels. These findings improve our understanding of the pathology of nonketotic hyperglycinemia and offer new perspectives for therapeutic options.
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Affiliation(s)
- Laura Arribas-Carreira
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Instituto de Biología Molecular, Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), 28049 Madrid, Spain
| | - Margarita Castro
- Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, 28029 Madrid, Spain
| | - Fernando García
- Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, 28029 Madrid, Spain
| | - Rosa Navarrete
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Instituto de Biología Molecular, Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, 28029 Madrid, Spain
| | - Irene Bravo-Alonso
- Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, 28029 Madrid, Spain
| | - Francisco Zafra
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Instituto de Biología Molecular, Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Instituto de Investigación Sanitaria Hospital La Paz (IdiPaz), ISCIII, 28029 Madrid, Spain
| | - Magdalena Ugarte
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Instituto de Biología Molecular, Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, 28029 Madrid, Spain
- Instituto de Investigación Sanitaria Hospital La Paz (IdiPaz), ISCIII, 28029 Madrid, Spain
| | - Eva Richard
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Instituto de Biología Molecular, Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, 28029 Madrid, Spain
- Instituto de Investigación Sanitaria Hospital La Paz (IdiPaz), ISCIII, 28029 Madrid, Spain
| | - Belén Pérez
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Instituto de Biología Molecular, Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, 28029 Madrid, Spain
- Instituto de Investigación Sanitaria Hospital La Paz (IdiPaz), ISCIII, 28029 Madrid, Spain
| | - Pilar Rodríguez-Pombo
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Instituto de Biología Molecular, Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, 28029 Madrid, Spain
- Instituto de Investigación Sanitaria Hospital La Paz (IdiPaz), ISCIII, 28029 Madrid, Spain
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5
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Katane M, Homma H. Biosynthesis and Degradation of Free D-Amino Acids and Their Physiological Roles in the Periphery and Endocrine Glands. Biol Pharm Bull 2024; 47:562-579. [PMID: 38432912 DOI: 10.1248/bpb.b23-00485] [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: 03/05/2024]
Abstract
It was long believed that D-amino acids were either unnatural isomers or laboratory artifacts, and that the important functions of amino acids were exerted only by L-amino acids. However, recent investigations have revealed a variety of D-amino acids in mammals that play important roles in physiological functions, including free D-serine and D-aspartate that are crucial in the central nervous system. The functions of several D-amino acids in the periphery and endocrine glands are also receiving increasing attention. Here, we present an overview of recent advances in elucidating the physiological roles of D-amino acids, especially in the periphery and endocrine glands.
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Affiliation(s)
- Masumi Katane
- Medicinal Research Laboratories, Graduate School of Pharmaceutical Sciences, Kitasato University
| | - Hiroshi Homma
- Laboratory of Analytical Chemistry, Graduate School of Pharmaceutical Sciences, Kitasato University
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6
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Abreu DS, Gomes JI, Ribeiro FF, Diógenes MJ, Sebastião AM, Vaz SH. Astrocytes control hippocampal synaptic plasticity through the vesicular-dependent release of D-serine. Front Cell Neurosci 2023; 17:1282841. [PMID: 38145284 PMCID: PMC10740624 DOI: 10.3389/fncel.2023.1282841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 11/10/2023] [Indexed: 12/26/2023] Open
Abstract
Astrocytes, the most abundant glial cells in the central nervous system (CNS), sense synaptic activity and respond through the release of gliotransmitters, a process mediated by intracellular Ca2+ level changes and SNARE-dependent mechanisms. Ionotropic N-methyl-D-aspartate (NMDA) receptors, which are activated by glutamate along with D-serine or glycine, play a crucial role in learning, memory, and synaptic plasticity. However, the precise impact of astrocyte-released D-serine on neuronal modulation remains insufficiently characterized. To address this, we have used the dominant negative SNARE (dnSNARE) mouse model, which selectively inhibits SNARE-dependent exocytosis from astrocytes. We recorded field excitatory postsynaptic potentials (fEPSPs) in CA3-CA1 synapses within hippocampal slices obtained from dnSNARE mice and wild-type (Wt) littermates. Our results demonstrate that hippocampal θ-burst long-term potentiation (LTP), a critical form of synaptic plasticity, is impaired in hippocampal slices from dnSNARE mice. Notably, this LTP impairment was rescued upon incubation with D-serine. To further investigate the involvement of astrocytes in D-serine-mediated mechanisms of LTP maintenance, we perfused hippocampal slices with L-serine - a substrate used by both neurons and astrocytes for D-serine production. The enhancement in LTP observed in dnSNARE mice was exclusively associated with D-serine presence, with no effects evident in the presence of L-serine. Additionally, both D- and L-serine reduced basal synaptic strength in the hippocampal slices of both Wt and dnSNARE mice. These results provide compelling evidence that distinct processes underlie the modulation of basal synaptic transmission and LTP through D-serine. Our findings underscore the pivotal contribution of astrocytes in D-serine-mediated processes that govern LTP establishment and basal transmission. This study not only provides essential insights into the intricate interplay between neurons and astrocytes but also emphasizes their collective role in shaping hippocampal synaptic function.
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Affiliation(s)
- Daniela Sofia Abreu
- Faculdade de Medicina, Instituto de Medicina Molecular João Lobo Antunes, Universidade de Lisboa, Lisbon, Portugal
- Faculdade de Medicina, Instituto de Farmacologia e Neurociências, Universidade de Lisboa, Lisbon, Portugal
| | - Joana I. Gomes
- Faculdade de Medicina, Instituto de Medicina Molecular João Lobo Antunes, Universidade de Lisboa, Lisbon, Portugal
- Faculdade de Medicina, Instituto de Farmacologia e Neurociências, Universidade de Lisboa, Lisbon, Portugal
| | - Filipa F. Ribeiro
- Faculdade de Medicina, Instituto de Medicina Molecular João Lobo Antunes, Universidade de Lisboa, Lisbon, Portugal
- Faculdade de Medicina, Instituto de Farmacologia e Neurociências, Universidade de Lisboa, Lisbon, Portugal
| | - Maria J. Diógenes
- Faculdade de Medicina, Instituto de Medicina Molecular João Lobo Antunes, Universidade de Lisboa, Lisbon, Portugal
- Faculdade de Medicina, Instituto de Farmacologia e Neurociências, Universidade de Lisboa, Lisbon, Portugal
| | - Ana M. Sebastião
- Faculdade de Medicina, Instituto de Medicina Molecular João Lobo Antunes, Universidade de Lisboa, Lisbon, Portugal
- Faculdade de Medicina, Instituto de Farmacologia e Neurociências, Universidade de Lisboa, Lisbon, Portugal
| | - Sandra H. Vaz
- Faculdade de Medicina, Instituto de Medicina Molecular João Lobo Antunes, Universidade de Lisboa, Lisbon, Portugal
- Faculdade de Medicina, Instituto de Farmacologia e Neurociências, Universidade de Lisboa, Lisbon, Portugal
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7
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Zhang YM, Qi YB, Gao YN, Chen WG, Zhou T, Zang Y, Li J. Astrocyte metabolism and signaling pathways in the CNS. Front Neurosci 2023; 17:1217451. [PMID: 37732313 PMCID: PMC10507181 DOI: 10.3389/fnins.2023.1217451] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 08/18/2023] [Indexed: 09/22/2023] Open
Abstract
Astrocytes comprise half of the cells in the central nervous system and play a critical role in maintaining metabolic homeostasis. Metabolic dysfunction in astrocytes has been indicated as the primary cause of neurological diseases, such as depression, Alzheimer's disease, and epilepsy. Although the metabolic functionalities of astrocytes are well known, their relationship to neurological disorders is poorly understood. The ways in which astrocytes regulate the metabolism of glucose, amino acids, and lipids have all been implicated in neurological diseases. Metabolism in astrocytes has also exhibited a significant influence on neuron functionality and the brain's neuro-network. In this review, we focused on metabolic processes present in astrocytes, most notably the glucose metabolic pathway, the fatty acid metabolic pathway, and the amino-acid metabolic pathway. For glucose metabolism, we focused on the glycolysis pathway, pentose-phosphate pathway, and oxidative phosphorylation pathway. In fatty acid metabolism, we followed fatty acid oxidation, ketone body metabolism, and sphingolipid metabolism. For amino acid metabolism, we summarized neurotransmitter metabolism and the serine and kynurenine metabolic pathways. This review will provide an overview of functional changes in astrocyte metabolism and provide an overall perspective of current treatment and therapy for neurological disorders.
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Affiliation(s)
- Yong-mei Zhang
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, Zhejiang, China
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ying-bei Qi
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, Zhejiang, China
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ya-nan Gao
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
- Institute of Pharmaceutical Sciences, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Wen-gang Chen
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
- Institute of Pharmaceutical Sciences, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Ting Zhou
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yi Zang
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jia Li
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, Zhejiang, China
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
- Institute of Pharmaceutical Sciences, China Pharmaceutical University, Nanjing, Jiangsu, China
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8
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Leng L, Yuan Z, Su X, Chen Z, Yang S, Chen M, Zhuang K, Lin H, Sun H, Li H, Xue M, Xu J, Yan J, Chen Z, Yuan T, Zhang J. Hypothalamic Menin regulates systemic aging and cognitive decline. PLoS Biol 2023; 21:e3002033. [PMID: 36928253 PMCID: PMC10019680 DOI: 10.1371/journal.pbio.3002033] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 02/09/2023] [Indexed: 03/18/2023] Open
Abstract
Aging is a systemic process, which is a risk factor for impaired physiological functions, and finally death. The molecular mechanisms driving aging process and the associated cognitive decline are not fully understood. The hypothalamus acts as the arbiter that orchestrates systemic aging through neuroinflammatory signaling. Our recent findings revealed that Menin plays important roles in neuroinflammation and brain development. Here, we found that the hypothalamic Menin signaling diminished in aged mice, which correlates with systemic aging and cognitive deficits. Restoring Menin expression in ventromedial nucleus of hypothalamus (VMH) of aged mice extended lifespan, improved learning and memory, and ameliorated aging biomarkers, while inhibiting Menin in VMH of middle-aged mice induced premature aging and accelerated cognitive decline. We further found that Menin epigenetically regulates neuroinflammatory and metabolic pathways, including D-serine metabolism. Aging-associated Menin reduction led to impaired D-serine release by VMH-hippocampus neural circuit, while D-serine supplement rescued cognitive decline in aged mice. Collectively, VMH Menin serves as a key regulator of systemic aging and aging-related cognitive decline.
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Affiliation(s)
- Lige Leng
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China
- * E-mail: (LL); (JZ)
| | - Ziqi Yuan
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Xiao Su
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Zhenlei Chen
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Shangchen Yang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Meiqin Chen
- College of Basic Medicine, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Kai Zhuang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Hui Lin
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Hao Sun
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Huifang Li
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Maoqiang Xue
- Department of Basic Medical Science, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Jun Xu
- Institute for AI in Medicine, School of Automation, Nanjing University of Information Science and Technology, Nanjing, China
| | - Jingqi Yan
- Center for Gene Regulation in Health and Disease, Cleveland State University, Cleveland, Ohio, United States of America
| | - Zhenyi Chen
- Department of Anesthesiology, First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
| | - Tifei Yuan
- Shanghai Mental Health Center, Shanghai Jiaotong University School of Medicine, Shanghai China
| | - Jie Zhang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China
- Department of Anesthesiology, First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
- * E-mail: (LL); (JZ)
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9
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Addendum to "Emerging evidence for astrocyte dysfunction in schizophrenia". Glia 2022; 70:2441-2442. [PMID: 36217806 PMCID: PMC10117557 DOI: 10.1002/glia.24275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/05/2022] [Indexed: 11/07/2022]
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10
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Kuo CY, Lin CH, Lane HY. Targeting D-Amino Acid Oxidase (DAAO) for the Treatment of Schizophrenia: Rationale and Current Status of Research. CNS Drugs 2022; 36:1143-1153. [PMID: 36194364 DOI: 10.1007/s40263-022-00959-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/14/2022] [Indexed: 11/29/2022]
Abstract
In the brain, D-amino acid oxidase (DAAO) is a peroxisomal flavoenzyme. Through oxidative deamination by DAAO, D-serine, the main coagonist of synaptic N-methyl-D-aspartate receptors (NMDARs), is degraded into α-keto acids and ammonia; flavin adenine dinucleotide (FAD) is simultaneously reduced to dihydroflavine-adenine dinucleotide (FADH2), which is subsequently reoxidized to FAD, with hydrogen peroxide produced as a byproduct. NMDAR hypofunction is implicated in the pathogenesis of schizophrenia. In previous studies, compared with control subjects, patients with schizophrenia had lower D-serine levels in peripheral blood and cerebrospinal fluid but higher DAAO expression and activity in the brain. Inhibiting DAAO activity and slowing D-serine degradation by using DAAO inhibitors to enhance NMDAR function may be a new strategy for use in the treatment of schizophrenia. The aim of this leading article is to review the current research in DAAO inhibitors.
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Affiliation(s)
- Chien-Yi Kuo
- Department of Psychiatry, China Medical University Hospital, No. 2, Yude Rd., North Dist., Taichung City, 404327, Taiwan, ROC.,Graduate Institute of Biomedical Sciences, China Medical University, No. 91, Xueshi Rd., North Dis., Taichung City, 404333, Taiwan, ROC
| | - Chieh-Hsin Lin
- Graduate Institute of Biomedical Sciences, China Medical University, No. 91, Xueshi Rd., North Dis., Taichung City, 404333, Taiwan, ROC. .,Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital, No. 123, Dapi Rd., Niaosong Dist., Kaohsiung City, 83301, Taiwan, ROC. .,School of Medicine, Chang Gung University, No. 259, Wenhua 1st Rd., Guishan Dist., Taoyuan City, 33302, Taiwan, ROC.
| | - Hsien-Yuan Lane
- Department of Psychiatry, China Medical University Hospital, No. 2, Yude Rd., North Dist., Taichung City, 404327, Taiwan, ROC. .,Graduate Institute of Biomedical Sciences, China Medical University, No. 91, Xueshi Rd., North Dis., Taichung City, 404333, Taiwan, ROC. .,Department of Psychology, College of Medical and Health Sciences, Asia University, No. 500, Lioufeng Rd., Wufeng Dist., Taichung City, 413305, Taiwan, ROC.
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11
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Maffioli E, Murtas G, Rabattoni V, Badone B, Tripodi F, Iannuzzi F, Licastro D, Nonnis S, Rinaldi AM, Motta Z, Sacchi S, Canu N, Tedeschi G, Coccetti P, Pollegioni L. Insulin and serine metabolism as sex-specific hallmarks of Alzheimer's disease in the human hippocampus. Cell Rep 2022; 40:111271. [PMID: 36070700 DOI: 10.1016/j.celrep.2022.111271] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 07/01/2022] [Accepted: 08/05/2022] [Indexed: 11/24/2022] Open
Abstract
Healthy aging is an ambitious aspiration for humans, but neurodegenerative disorders, such as Alzheimer's disease (AD), strongly affect quality of life. Using an integrated omics approach, we investigate alterations in the molecular composition of postmortem hippocampus samples of healthy persons and individuals with AD. Profound differences are apparent between control and AD male and female cohorts in terms of up- and downregulated metabolic pathways. A decrease in the insulin response is evident in AD when comparing the female with the male group. The serine metabolism (linked to the glycolytic pathway and generating the N-methyl-D-aspartate [NMDA] receptor coagonist D-serine) is also significantly modulated: the D-Ser/total serine ratio represents a way to counteract age-related cognitive decline in healthy men and during AD onset in women. These results show how AD changes and, in certain respects, almost reverses sex-specific proteomic and metabolomic profiles, highlighting how different pathophysiological mechanisms are active in men and women.
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Affiliation(s)
- Elisa Maffioli
- DIVAS, Department of Veterinary Medicine and Animal Science, University of Milano, 20121 Milano, Italy; CIMAINA, University of Milano, 20121 Milano, Italy
| | - Giulia Murtas
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy
| | - Valentina Rabattoni
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy
| | - Beatrice Badone
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, 20126 Milano, Italy
| | - Farida Tripodi
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, 20126 Milano, Italy
| | - Filomena Iannuzzi
- Department of System Medicine, University of Rome "Tor Vergata," 00133 Rome, Italy
| | | | - Simona Nonnis
- DIVAS, Department of Veterinary Medicine and Animal Science, University of Milano, 20121 Milano, Italy; CIMAINA, University of Milano, 20121 Milano, Italy
| | - Anna Maria Rinaldi
- Department of System Medicine, University of Rome "Tor Vergata," 00133 Rome, Italy
| | - Zoraide Motta
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy
| | - Silvia Sacchi
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy
| | - Nadia Canu
- Department of System Medicine, University of Rome "Tor Vergata," 00133 Rome, Italy; Istituto di Biochimica e Biologia Cellulare (IBBC) CNR, 00015 Monterotondo Scalo, Italy.
| | - Gabriella Tedeschi
- DIVAS, Department of Veterinary Medicine and Animal Science, University of Milano, 20121 Milano, Italy; CIMAINA, University of Milano, 20121 Milano, Italy.
| | - Paola Coccetti
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, 20126 Milano, Italy.
| | - Loredano Pollegioni
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy.
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12
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Swanson MA, Miller K, Young SP, Tong S, Ghaloul‐Gonzalez L, Neira‐Fresneda J, Schlichting L, Peck C, Gabel L, Friederich MW, Van Hove JLK. Cerebrospinal fluid amino acids glycine, serine, and threonine in nonketotic hyperglycinemia. J Inherit Metab Dis 2022; 45:734-747. [PMID: 35357708 PMCID: PMC9543955 DOI: 10.1002/jimd.12500] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 03/24/2022] [Accepted: 03/28/2022] [Indexed: 01/30/2023]
Abstract
Nonketotic hyperglycinemia (NKH) is caused by deficient glycine cleavage enzyme activity and characterized by elevated brain glycine. Metabolism of glycine is connected enzymatically to serine through serine hydroxymethyltransferase and shares transporters with serine and threonine. We aimed to evaluate changes in serine and threonine in NKH patients, and relate this to clinical outcome severity. Age-related reference values were developed for cerebrospinal fluid (CSF) serine and threonine from 274 controls, and in a cross-sectional study compared to 61 genetically proven NKH patients, categorized according to outcome. CSF d-serine and l-serine levels were stereoselectively determined in seven NKH patients and compared to 29 age-matched controls. In addition to elevated CSF glycine, NKH patients had significantly decreased levels of CSF serine and increased levels of CSF threonine, even after age-adjustment. The CSF serine/threonine ratio discriminated between NKH patients and controls. The CSF glycine/serine aided in discrimination between severe and attenuated neonates with NKH. Over all ages, the CSF glycine, serine and threonine had moderate to fair correlation with outcome classes. After age-adjustment, only the CSF glycine level provided good discrimination between outcome classes. In untreated patients, d-serine was more reduced than l-serine, with a decreased d/l-serine ratio, indicating a specific impact on d-serine metabolism. We conclude that in NKH the elevation of glycine is accompanied by changes in l-serine, d-serine and threonine, likely reflecting a perturbation of the serine shuttle and metabolism, and of one-carbon metabolism. This provides additional guidance on diagnosis and prognosis, and opens new therapeutic avenues to be explored.
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Affiliation(s)
- Michael A. Swanson
- Section of Clinical Genetics and Metabolism, Department of PediatricsUniversity of ColoradoAuroraColoradoUSA
| | - Kristen Miller
- Department of Pediatrics, Child Health Biostatistics CoreUniversity of Colorado and Children's Hospital ColoradoAuroraColoradoUSA
| | - Sarah P. Young
- Division of Medical Genetics, Department of PediatricsDuke University School of MedicineDurhamNorth CarolinaUSA
| | - Suhong Tong
- Department of Pediatrics, Child Health Biostatistics CoreUniversity of Colorado and Children's Hospital ColoradoAuroraColoradoUSA
| | - Lina Ghaloul‐Gonzalez
- Division of Genetic and Genomic Medicine, Department of PediatricsUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
- Department of Human GeneticsGraduate School of Public Health, University of PittsburghPittsburghPennsylvaniaUSA
| | | | - Lisa Schlichting
- Department of Pathology and Laboratory MedicineChildren's Hospital ColoradoAuroraColoradoUSA
| | - Cheryl Peck
- Department of Pathology and Laboratory MedicineChildren's Hospital ColoradoAuroraColoradoUSA
| | - Linda Gabel
- Department of Pathology and Laboratory MedicineChildren's Hospital ColoradoAuroraColoradoUSA
| | - Marisa W. Friederich
- Section of Clinical Genetics and Metabolism, Department of PediatricsUniversity of ColoradoAuroraColoradoUSA
- Department of Pathology and Laboratory MedicineChildren's Hospital ColoradoAuroraColoradoUSA
| | - Johan L. K. Van Hove
- Section of Clinical Genetics and Metabolism, Department of PediatricsUniversity of ColoradoAuroraColoradoUSA
- Department of Pathology and Laboratory MedicineChildren's Hospital ColoradoAuroraColoradoUSA
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13
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Tapanes SA, Arizanovska D, Díaz MM, Folorunso OO, Harvey T, Brown SE, Radzishevsky I, Close LN, Jagid JR, Graciolli Cordeiro J, Wolosker H, Balu DT, Liebl DJ. Inhibition of glial D-serine release rescues synaptic damage after brain injury. Glia 2022; 70:1133-1152. [PMID: 35195906 PMCID: PMC9305835 DOI: 10.1002/glia.24161] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 01/13/2022] [Accepted: 02/04/2022] [Indexed: 11/28/2022]
Abstract
Synaptic damage is one of the most prevalent pathophysiological responses to traumatic CNS injury and underlies much of the associated cognitive dysfunction; however, it is poorly understood. The D-amino acid, D-serine, serves as the primary co-agonist at synaptic NMDA receptors (NDMARs) and is a critical mediator of NMDAR-dependent transmission and synaptic plasticity. In physiological conditions, D-serine is produced and released by neurons from the enzymatic conversion of L-serine by serine racemase (SRR). However, under inflammatory conditions, glial cells become a major source of D-serine. Here, we report that D-serine synthesized by reactive glia plays a critical role in synaptic damage after traumatic brain injury (TBI) and identify the therapeutic potential of inhibiting glial D-serine release though the transporter Slc1a4 (ASCT1). Furthermore, using cell-specific genetic strategies and pharmacology, we demonstrate that TBI-induced synaptic damage and memory impairment requires D-serine synthesis and release from both reactive astrocytes and microglia. Analysis of the murine cortex and acutely resected human TBI brain also show increased SRR and Slc1a4 levels. Together, these findings support a novel role for glial D-serine in acute pathological dysfunction following brain trauma, whereby these reactive cells provide the excess co-agonist levels necessary to initiate NMDAR-mediated synaptic damage.
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Affiliation(s)
- Stephen A. Tapanes
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Dena Arizanovska
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Madelen M. Díaz
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Oluwarotimi O. Folorunso
- Department of PsychiatryHarvard Medical SchoolBostonMassachusettsUSA
- Translational Psychiatry LaboratoryMcLean HospitalBelmontMassachusettsUSA
| | - Theresa Harvey
- Translational Psychiatry LaboratoryMcLean HospitalBelmontMassachusettsUSA
| | - Stephanie E. Brown
- Translational Psychiatry LaboratoryMcLean HospitalBelmontMassachusettsUSA
| | - Inna Radzishevsky
- Department of Biochemistry, Rappaport Faculty of MedicineTechnion‐Israel Institute of TechnologyHaifaIsrael
| | - Liesl N. Close
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Jonathan R. Jagid
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Joacir Graciolli Cordeiro
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Herman Wolosker
- Department of Biochemistry, Rappaport Faculty of MedicineTechnion‐Israel Institute of TechnologyHaifaIsrael
| | - Darrick T. Balu
- Department of PsychiatryHarvard Medical SchoolBostonMassachusettsUSA
- Translational Psychiatry LaboratoryMcLean HospitalBelmontMassachusettsUSA
| | - Daniel J. Liebl
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
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14
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Seetharam JC, Maiti R, Mishra A, Mishra BR. Efficacy and safety of add-on sodium benzoate, a D-amino acid oxidase inhibitor, in treatment of schizophrenia: A systematic review and meta-analysis. Asian J Psychiatr 2022; 68:102947. [PMID: 34890931 DOI: 10.1016/j.ajp.2021.102947] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/22/2021] [Accepted: 11/26/2021] [Indexed: 02/04/2023]
Abstract
BACKGROUND The role of sodium benzoate, an NMDA receptor enhancer, in schizophrenia has been evaluated in a few clinical trials, but results are contradictory and inconclusive. The present meta-analysis has evaluated the efficacy and safety of add-on sodium benzoate for the treatment of schizophrenia. METHODS After performing a literature search on MEDLINE/PubMed, Scopus, Cochrane databases and International Clinical Trial Registry Platform, reviewers assessed eligibility and extracted data from four relevant articles. PRISMA guidelines were followed in the selection, analysis, and reporting of findings. The random-effect model was used to estimate effect size. Quality assessment was done using the risk of bias assessment tool, and sensitivity analysis was done in case of high heterogeneity. RESULTS Add-on sodium benzoate can improve positive symptoms of schizophrenia significantly (MD: -1.87; 95%CI: -3.25 to -0.48; p = 0.008) but had no significant favourable effect on negative symptoms (p = 0.84), general psychopathology (p = 0.49), and total PANSS score (p = 0.19) over the control. There was no significant improvement in GAF (p = 0.43), CGI (p = 0.58), cognitive function (p = 0.46) and quality of life (p = 0.73). Extrapyramidal symptoms were significantly higher (MD: 0.39; 95% CI:0.19-0.60; p = 0.0002) in the sodium benzoate group in comparison to the control group; however, there was no significant difference in respect to other adverse events. CONCLUSION Sodium benzoate can improve the positive symptoms of schizophrenia without any beneficial effect on other symptomatology, cognition, quality of life and functioning. Further studies are needed to evaluate long-term efficacy, safety and use in specific subgroups of patients.
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Affiliation(s)
| | - Rituparna Maiti
- Department of Pharmacology All India Institute of Medical Sciences (AIIMS), Bhubaneswar, India.
| | - Archana Mishra
- Department of Pharmacology All India Institute of Medical Sciences (AIIMS), New Delhi, India.
| | - Biswa Ranjan Mishra
- Department of Psychiatry All India Institute of Medical Sciences (AIIMS), Bhubaneswar, India.
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15
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Abstract
Astroglia are key regulators of synaptic function, playing central roles in homeostatic ion buffering, energy dynamics, transmitter uptake, maintenance of neurotransmitter pools, and regulation of synaptic plasticity through release of neuroactive chemicals. Given the myriad of crucial homeostatic and signaling functions attributed to astrocytes and the variety of neurotransmitter receptors expressed by astroglia, they serve as prime cellular candidates for establishing maladaptive synaptic plasticity following drug exposure. Initial studies on astroglia and addiction have placed drug-mediated disruptions in the homeostatic regulation of glutamate as a central aspect of relapse vulnerability. However, the generation of sophisticated tools to study and manipulate astroglia have proven that the interaction between addictive substances, astroglia, and relapse-relevant synaptic plasticity extends far beyond the homeostatic regulation of glutamate. Here we present astroglial systems impacted by drug exposure and discuss how changes in astroglial biology contribute to addiction biology.
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16
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d-Amino Acids and pLG72 in Alzheimer's Disease and Schizophrenia. Int J Mol Sci 2021; 22:ijms222010917. [PMID: 34681579 PMCID: PMC8535920 DOI: 10.3390/ijms222010917] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/01/2021] [Accepted: 10/06/2021] [Indexed: 01/02/2023] Open
Abstract
Numerous studies over the last several years have shown that d-amino acids, especially d-serine, have been related to brain and neurological disorders. Acknowledged neurological functions of d-amino acids include neurotransmission and learning and memory functions through modulating N-methyl-d-aspartate type glutamate receptors (NMDARs). Aberrant d-amino acids level and polymorphisms of genes related to d-amino acids metabolism are associated with neurodegenerative brain conditions. This review summarizes the roles of d-amino acids and pLG72, also known as d-amino acid oxidase activator, on two neurodegenerative disorders, schizophrenia and Alzheimer’s disease (AD). The scope includes the changes in d-amino acids levels, gene polymorphisms of G72 genomics, and the role of pLG72 on NMDARs and mitochondria in schizophrenia and AD. The clinical diagnostic value of d-amino acids and pLG72 and the therapeutic importance are also reviewed.
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17
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Stehantsev P, Stetsenko A, Nemchinova M, Aduri NG, Marrink SJ, Gati C, Guskov A. A structural view onto disease-linked mutations in the human neutral amino acid exchanger ASCT1. Comput Struct Biotechnol J 2021; 19:5246-5254. [PMID: 34630942 PMCID: PMC8479201 DOI: 10.1016/j.csbj.2021.09.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/14/2021] [Accepted: 09/14/2021] [Indexed: 01/30/2023] Open
Abstract
The ASCT1 transporter of the SLC1 family is largely involved in equilibration of neutral amino acids' pools across the plasma membrane and plays a prominent role in the transport of both L- and D-isomers of serine, essential for the normal functioning of the central nervous system in mammals. A number of mutations in ASCT1 (E256K, G381R, R457W) have been linked to severe neurodevelopmental disorders, however in the absence of ASCT1 structure it is hard to understand their impact on substrate transport. To ameliorate that we have determined a cryo-EM structure of human ASCT1 at 4.2 Å resolution and performed functional transport assays and molecular dynamics simulations, which revealed that given mutations lead to the diminished transport capability of ASCT1 caused by instability of transporter and impeded transport cycle.
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Affiliation(s)
- Pavlo Stehantsev
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, The Netherlands
| | - Artem Stetsenko
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, The Netherlands
| | - Mariia Nemchinova
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, The Netherlands
| | - Nanda Gowtham Aduri
- Department of Biological Sciences, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA, USA
| | - Siewert J. Marrink
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, The Netherlands
| | - Cornelius Gati
- Department of Biological Sciences, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA, USA
| | - Albert Guskov
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, The Netherlands
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia
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18
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Piubelli L, Murtas G, Rabattoni V, Pollegioni L. The Role of D-Amino Acids in Alzheimer's Disease. J Alzheimers Dis 2021; 80:475-492. [PMID: 33554911 DOI: 10.3233/jad-201217] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Alzheimer's disease (AD), the main cause of dementia worldwide, is characterized by a complex and multifactorial etiology. In large part, excitatory neurotransmission in the central nervous system is mediated by glutamate and its receptors are involved in synaptic plasticity. The N-methyl-D-aspartate (NMDA) receptors, which require the agonist glutamate and a coagonist such as glycine or the D-enantiomer of serine for activation, play a main role here. A second D-amino acid, D-aspartate, acts as agonist of NMDA receptors. D-amino acids, present in low amounts in nature and long considered to be of bacterial origin, have distinctive functions in mammals. In recent years, alterations in physiological levels of various D-amino acids have been linked to various pathological states, ranging from chronic kidney disease to neurological disorders. Actually, the level of NMDA receptor signaling must be balanced to promote neuronal survival and prevent neurodegeneration: this signaling in AD is affected mainly by glutamate availability and modulation of the receptor's functions. Here, we report the experimental findings linking D-serine and D-aspartate, through NMDA receptor modulation, to AD and cognitive functions. Interestingly, AD progression has been also associated with the enzymes related to D-amino acid metabolism as well as with glucose and serine metabolism. Furthermore, the D-serine and D-/total serine ratio in serum have been recently proposed as biomarkers of AD progression. A greater understanding of the role of D-amino acids in excitotoxicity related to the pathogenesis of AD will facilitate novel therapeutic treatments to cure the disease and improve life expectancy.
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Affiliation(s)
- Luciano Piubelli
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Giulia Murtas
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Valentina Rabattoni
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Loredano Pollegioni
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
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19
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Astrocytic contribution to glutamate-related central respiratory chemoreception in vertebrates. Respir Physiol Neurobiol 2021; 294:103744. [PMID: 34302992 DOI: 10.1016/j.resp.2021.103744] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 07/01/2021] [Accepted: 07/18/2021] [Indexed: 12/24/2022]
Abstract
Central respiratory chemoreceptors play a key role in the respiratory homeostasis by sensing CO2 and H+ in brain and activating the respiratory neural network. This ability of specific brain regions to respond to acidosis and hypercapnia is based on neuronal and glial mechanisms. Several decades ago, glutamatergic transmission was proposed to be involved as a main mechanism in central chemoreception. However, a complete identification of mechanism has been elusive. At the rostral medulla, chemosensitive neurons of the retrotrapezoid nucleus (RTN) are glutamatergic and they are stimulated by ATP released by RTN astrocytes in response to hypercapnia. In addition, recent findings show that caudal medullary astrocytes in brainstem can also contribute as CO2 and H+ sensors that release D-serine and glutamate, both gliotransmitters able to activate the respiratory neural network. In this review, we describe the mammalian astrocytic glutamatergic contribution to the central respiratory chemoreception trying to trace in vertebrates the emergence of several components involved in this process.
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20
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Sherwood MW, Oliet SHR, Panatier A. NMDARs, Coincidence Detectors of Astrocytic and Neuronal Activities. Int J Mol Sci 2021; 22:7258. [PMID: 34298875 PMCID: PMC8307462 DOI: 10.3390/ijms22147258] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/30/2021] [Accepted: 06/30/2021] [Indexed: 12/18/2022] Open
Abstract
Synaptic plasticity is an extensively studied cellular correlate of learning and memory in which NMDARs play a starring role. One of the most interesting features of NMDARs is their ability to act as a co-incident detector. It is unique amongst neurotransmitter receptors in this respect. Co-incident detection is possible because the opening of NMDARs requires membrane depolarisation and the binding of glutamate. Opening of NMDARs also requires a co-agonist. Although the dynamic regulation of glutamate and membrane depolarization have been well studied in coincident detection, the role of the co-agonist site is unexplored. It turns out that non-neuronal glial cells, astrocytes, regulate co-agonist availability, giving them the ability to influence synaptic plasticity. The unique morphology and spatial arrangement of astrocytes at the synaptic level affords them the capacity to sample and integrate information originating from unrelated synapses, regardless of any pre-synaptic and post-synaptic commonality. As astrocytes are classically considered slow responders, their influence at the synapse is widely recognized as modulatory. The aim herein is to reconsider the potential of astrocytes to participate directly in ongoing synaptic NMDAR activity and co-incident detection.
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Affiliation(s)
- Mark W. Sherwood
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, F-3300 Bordeaux, France;
| | | | - Aude Panatier
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, F-3300 Bordeaux, France;
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21
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Lloyd MD, Yevglevskis M, Nathubhai A, James TD, Threadgill MD, Woodman TJ. Racemases and epimerases operating through a 1,1-proton transfer mechanism: reactivity, mechanism and inhibition. Chem Soc Rev 2021; 50:5952-5984. [PMID: 34027955 PMCID: PMC8142540 DOI: 10.1039/d0cs00540a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Indexed: 12/12/2022]
Abstract
Racemases and epimerases catalyse changes in the stereochemical configurations of chiral centres and are of interest as model enzymes and as biotechnological tools. They also occupy pivotal positions within metabolic pathways and, hence, many of them are important drug targets. This review summarises the catalytic mechanisms of PLP-dependent, enolase family and cofactor-independent racemases and epimerases operating by a deprotonation/reprotonation (1,1-proton transfer) mechanism and methods for measuring their catalytic activity. Strategies for inhibiting these enzymes are reviewed, as are specific examples of inhibitors. Rational design of inhibitors based on substrates has been extensively explored but there is considerable scope for development of transition-state mimics and covalent inhibitors and for the identification of inhibitors by high-throughput, fragment and virtual screening approaches. The increasing availability of enzyme structures obtained using X-ray crystallography will facilitate development of inhibitors by rational design and fragment screening, whilst protein models will facilitate development of transition-state mimics.
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Affiliation(s)
- Matthew D Lloyd
- Drug & Target Discovery, Department of Pharmacy & Pharmacology, University of Bath, Claverton Down, Bath BA2 7AY, UK.
| | - Maksims Yevglevskis
- Drug & Target Discovery, Department of Pharmacy & Pharmacology, University of Bath, Claverton Down, Bath BA2 7AY, UK. and CatSci Ltd., CBTC2, Capital Business Park, Wentloog, Cardiff CF3 2PX, UK
| | - Amit Nathubhai
- Drug & Target Discovery, Department of Pharmacy & Pharmacology, University of Bath, Claverton Down, Bath BA2 7AY, UK. and University of Sunderland, School of Pharmacy & Pharmaceutical Sciences, Sciences Complex, Sunderland SR1 3SD, UK
| | - Tony D James
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK and School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, People's Republic of China
| | - Michael D Threadgill
- Drug & Target Discovery, Department of Pharmacy & Pharmacology, University of Bath, Claverton Down, Bath BA2 7AY, UK. and Institute of Biological, Environmental & Rural Sciences, Aberystwyth University, Aberystwyth SY23 3BY, UK
| | - Timothy J Woodman
- Drug & Target Discovery, Department of Pharmacy & Pharmacology, University of Bath, Claverton Down, Bath BA2 7AY, UK.
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22
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Rabattoni V, Pollegioni L, Tedeschi G, Maffioli E, Sacchi S. Cellular studies of the two main isoforms of human d-aspartate oxidase. FEBS J 2021; 288:4939-4954. [PMID: 33650155 DOI: 10.1111/febs.15797] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 01/21/2021] [Accepted: 02/26/2021] [Indexed: 01/01/2023]
Abstract
Human d-aspartate oxidase (hDASPO) is a FAD-dependent enzyme responsible for the degradation of d-aspartate (d-Asp). In the mammalian central nervous system, d-Asp behaves as a classical neurotransmitter, it is thought to be involved in neural development, brain morphology and behavior, and appears to be involved in several pathological states, such as schizophrenia and Alzheimer's disease. Apparently, the human DDO gene produces alternative transcripts encoding for three putative hDASPO isoforms, constituted by 341 (the 'canonical' form), 369, and 282 amino acids. Despite the increasing interest in hDASPO and its physiological role, little is known about these different isoforms. Here, the additional N-terminal peptide present in the hDASPO_369 isoform only has been identified in hippocampus of Alzheimer's disease female patients, while peptides corresponding to the remaining part of the protein were present in samples from male and female healthy controls and Alzheimer's disease patients. The hDASPO_369 isoform was largely expressed in E. coli as insoluble protein, hampering with its biochemical characterization. Furthermore, we generated U87 human glioblastoma cell clones stably expressing hDASPO_341 and, for the first time, hDASPO_369 isoforms; the latter protein showed a lower expression compared with the canonical isoform. Both protein isoforms are active (showing similar kinetic properties), localize to the peroxisomes, are very stable (a half-life of approximately 100 h has been estimated), and are primarily degraded through the ubiquitin-proteasome system. These studies shed light on the properties of hDASPO isoforms with the final aim to clarify the mechanisms controlling brain levels of the neuromodulator d-Asp.
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Affiliation(s)
- Valentina Rabattoni
- "The Protein Factory 2.0", Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, Varese, Italy
| | - Loredano Pollegioni
- "The Protein Factory 2.0", Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, Varese, Italy
| | - Gabriella Tedeschi
- Università degli Studi di Milano, DIMEVET - Dipartimento di Medicina Veterinaria, Milano, Italy
| | - Elisa Maffioli
- Università degli Studi di Milano, DIMEVET - Dipartimento di Medicina Veterinaria, Milano, Italy
| | - Silvia Sacchi
- "The Protein Factory 2.0", Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, Varese, Italy
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23
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Shen J. D-Amino acid substituted peptides as potential alternatives of homochiral L-configurations. Amino Acids 2021; 53:265-280. [PMID: 33537892 DOI: 10.1007/s00726-021-02947-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 01/22/2021] [Indexed: 11/28/2022]
Abstract
On the primitive Earth, both L- and D-amino acids would have been present. However, only L-amino acids are essential blocks to construct proteins in modern life. To study the relative stability of D-amino acid substituted peptides, a variety of computational methods were applied. Ten prebiotic amino acids (Gly, Ala, Asp, Glu, Ile, Leu, Pro, Ser, Thr, and Val) were previously determined by multiple meteorite, spark discharge, and hydrothermal vent studies. Some previously reported early Earth polypeptide analogs were focused on in this study. Tripeptides composed of only Asp, Ser, and Val exemplified that different positions (i.e., N-terminus, C-terminus, and middle) made a difference in the minimal folding energy of peptides, while the chemical classification of amino acid (hydrophobic, acidic, or hydroxylic) did not show a significant difference. Hierarchical cluster analysis for dipeptides with all possible combinations of the proposed ten prebiotic amino acids and their D-amino acid substituted derivatives generated five clusters. Primordial simple polypeptides were modeled to test the significance of molecular fluctuations, secondary structure occupancies, and folding energy differences based on these clusters. We found peptides with α-helices, long β-sheets, and long loops are usually less sensitive to D-amino acid replacements in comparison to short β-sheets. Intriguingly, amongst 129 D-amino acid residues, mutation sensitivity profiles presented that the ratio of more to less stable residues was about 1. In conclusion, some combinations of a mixture of L- and D-amino acids can potentially act as essential building blocks of life.
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Affiliation(s)
- Jianxun Shen
- School of Earth and Environmental Sciences and Centre for Exoplanet Science, University of St Andrews, St Andrews, KY16 9AL, UK.
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24
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Pei JC, Luo DZ, Gau SS, Chang CY, Lai WS. Directly and Indirectly Targeting the Glycine Modulatory Site to Modulate NMDA Receptor Function to Address Unmet Medical Needs of Patients With Schizophrenia. Front Psychiatry 2021; 12:742058. [PMID: 34658976 PMCID: PMC8517243 DOI: 10.3389/fpsyt.2021.742058] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 09/02/2021] [Indexed: 12/30/2022] Open
Abstract
Schizophrenia is a severe mental illness that affects ~1% of the world's population. It is clinically characterized by positive, negative, and cognitive symptoms. Currently available antipsychotic medications are relatively ineffective in improving negative and cognitive deficits, which are related to a patient's functional outcomes and quality of life. Negative symptoms and cognitive deficits are unmet by the antipsychotic medications developed to date. In recent decades, compelling animal and clinical studies have supported the NMDA receptor (NMDAR) hypofunction hypothesis of schizophrenia and have suggested some promising therapeutic agents. Notably, several NMDAR-enhancing agents, especially those that function through the glycine modulatory site (GMS) of NMDAR, cause significant reduction in psychotic and cognitive symptoms in patients with schizophrenia. Given that the NMDAR-mediated signaling pathway has been implicated in cognitive/social functions and that GMS is a potential therapeutic target for enhancing the activation of NMDARs, there is great interest in investigating the effects of direct and indirect GMS modulators and their therapeutic potential. In this review, we focus on describing preclinical and clinical studies of direct and indirect GMS modulators in the treatment of schizophrenia, including glycine, D-cycloserine, D-serine, glycine transporter 1 (GlyT1) inhibitors, and D-amino acid oxidase (DAO or DAAO) inhibitors. We highlight some of the most promising recently developed pharmacological compounds designed to either directly or indirectly target GMS and thus augment NMDAR function to treat the cognitive and negative symptoms of schizophrenia. Overall, the current findings suggest that indirectly targeting of GMS appears to be more beneficial and leads to less adverse effects than direct targeting of GMS to modulate NMDAR functions. Indirect GMS modulators, especially GlyT1 inhibitors and DAO inhibitors, open new avenues for the treatment of unmet medical needs for patients with schizophrenia.
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Affiliation(s)
- Ju-Chun Pei
- Department of Psychology, National Taiwan University, Taipei, Taiwan
| | - Da-Zhong Luo
- Department of Psychology, National Taiwan University, Taipei, Taiwan
| | - Shiang-Shin Gau
- Department of Psychology, National Taiwan University, Taipei, Taiwan
| | - Chia-Yuan Chang
- Department of Psychology, National Taiwan University, Taipei, Taiwan.,Neurobiology and Cognitive Science Center, National Taiwan University, Taipei, Taiwan
| | - Wen-Sung Lai
- Department of Psychology, National Taiwan University, Taipei, Taiwan.,Neurobiology and Cognitive Science Center, National Taiwan University, Taipei, Taiwan.,Graduate Institute of Brain and Mind Sciences, National Taiwan University, Taipei, Taiwan
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25
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Murtas G, Marcone GL, Sacchi S, Pollegioni L. L-serine synthesis via the phosphorylated pathway in humans. Cell Mol Life Sci 2020; 77:5131-5148. [PMID: 32594192 PMCID: PMC11105101 DOI: 10.1007/s00018-020-03574-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 06/03/2020] [Accepted: 06/12/2020] [Indexed: 12/12/2022]
Abstract
L-serine is a nonessential amino acid in eukaryotic cells, used for protein synthesis and in producing phosphoglycerides, glycerides, sphingolipids, phosphatidylserine, and methylenetetrahydrofolate. Moreover, L-serine is the precursor of two relevant coagonists of NMDA receptors: glycine (through the enzyme serine hydroxymethyltransferase), which preferentially acts on extrasynaptic receptors and D-serine (through the enzyme serine racemase), dominant at synaptic receptors. The cytosolic "phosphorylated pathway" regulates de novo biosynthesis of L-serine, employing 3-phosphoglycerate generated by glycolysis and the enzymes 3-phosphoglycerate dehydrogenase, phosphoserine aminotransferase, and phosphoserine phosphatase (the latter representing the irreversible step). In the human brain, L-serine is primarily found in glial cells and is supplied to neurons for D-serine synthesis. Serine-deficient patients show severe neurological symptoms, including congenital microcephaly, psychomotor retardation, and intractable seizures, thus highlighting the relevance of de novo production of this amino acid in brain development and morphogenesis. Indeed, the phosphorylated pathway is strictly linked to cancer. Moreover, L-serine has been suggested as a ready-to-use treatment, as also recently proposed for Alzheimer's disease. Here, we present our current state of knowledge concerning the three mammalian enzymes of the phosphorylated pathway and known mutations related to pathological conditions: although the structure of these enzymes has been solved, how enzyme activity is regulated remains largely unknown. We believe that an in-depth investigation of these enzymes is crucial to identify the molecular mechanisms involved in modulating concentrations of the serine enantiomers and for studying the interplay between glial and neuronal cells and also to determine the most suitable therapeutic approach for various diseases.
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Affiliation(s)
- Giulia Murtas
- Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100, Varese, Italy
| | - Giorgia Letizia Marcone
- Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100, Varese, Italy
| | - Silvia Sacchi
- Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100, Varese, Italy
| | - Loredano Pollegioni
- Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100, Varese, Italy.
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26
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Zhao J, Taylor CJ, Newcombe EA, Spanevello MD, O'Keeffe I, Cooper LT, Jhaveri DJ, Boyd AW, Bartlett PF. EphA4 Regulates Hippocampal Neural Precursor Proliferation in the Adult Mouse Brain by d-Serine Modulation of N-Methyl-d-Aspartate Receptor Signaling. Cereb Cortex 2020; 29:4381-4397. [PMID: 30590507 DOI: 10.1093/cercor/bhy319] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 11/20/2018] [Accepted: 11/22/2018] [Indexed: 12/14/2022] Open
Abstract
The hippocampal dentate gyrus (DG) is a major region of the adult rodent brain in which neurogenesis occurs throughout life. The EphA4 receptor, which regulates neurogenesis and boundary formation in the developing brain, is also expressed in the adult DG, but whether it regulates adult hippocampal neurogenesis is not known. Here, we show that, in the adult mouse brain, EphA4 inhibits hippocampal precursor cell proliferation but does not affect precursor differentiation or survival. Genetic deletion or pharmacological inhibition of EphA4 significantly increased hippocampal precursor proliferation in vivo and in vitro, by blocking EphA4 forward signaling. EphA4 was expressed by mature hippocampal DG neurons but not neural precursor cells, and an EphA4 antagonist, EphA4-Fc, did not activate clonal cultures of precursors until they were co-cultured with non-precursor cells, indicating an indirect effect of EphA4 on the regulation of precursor activity. Supplementation with d-serine blocked the increased precursor proliferation induced by EphA4 inhibition, whereas blocking the interaction between d-serine and N-methyl-d-aspartate receptors (NMDARs) promoted precursor activity, even at the clonal level. Collectively, these findings demonstrate that EphA4 indirectly regulates adult hippocampal precursor proliferation and thus plays a role in neurogenesis via d-serine-regulated NMDAR signaling.
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Affiliation(s)
- Jing Zhao
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Chanel J Taylor
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Estella A Newcombe
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Mark D Spanevello
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Imogen O'Keeffe
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Leanne T Cooper
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia.,QIMR Berghofer Medical Research Institute, St Lucia, QLD, Australia
| | - Dhanisha J Jhaveri
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia.,Mater Research Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Andrew W Boyd
- QIMR Berghofer Medical Research Institute, St Lucia, QLD, Australia.,School of Medicine, The University of Queensland, St Lucia, QLD, Australia
| | - Perry F Bartlett
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
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27
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Abstract
Opioids are the most powerful analgesics available to date. However, they may also induce adverse effects including paradoxical opioid-induced hyperalgesia. A mechanism that might underlie opioid-induced hyperalgesia is the amplification of synaptic strength at spinal C-fibre synapses after withdrawal from systemic opioids such as remifentanil ("opioid-withdrawal long-term potentiation [LTP]"). Here, we show that both the induction as well as the maintenance of opioid-withdrawal LTP were abolished by pharmacological blockade of spinal glial cells. By contrast, the blockade of TLR4 had no effect on the induction of opioid-withdrawal LTP. D-serine, which may be released upon glial cell activation, was necessary for withdrawal LTP. D-serine is the dominant coagonist for neuronal NMDA receptors, which are required for the amplification of synaptic strength on remifentanil withdrawal. Unexpectedly, opioid-withdrawal LTP was transferable through the cerebrospinal fluid between animals. This suggests that glial-cell-derived mediators accumulate in the extracellular space and reach the cerebrospinal fluid at biologically active concentrations, thereby creating a soluble memory trace that is transferable to another animal ("transfer LTP"). When we enzymatically degraded D-serine in the superfusate, LTP could no longer be transferred. Transfer LTP was insensitive to pharmacological blockade of glial cells in the recipient animal, thus representing a rare form of glial cell-independent LTP in the spinal cord.
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28
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Solid-state vibrational circular dichroism studies on the conformation of an amino acid molecule in crystalline state. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1868:140439. [DOI: 10.1016/j.bbapap.2020.140439] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 04/18/2020] [Accepted: 04/29/2020] [Indexed: 11/20/2022]
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29
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Puggioni V, Savinelli A, Miceli M, Molla G, Pollegioni L, Sacchi S. Biochemical characterization of mouse d-aspartate oxidase. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1868:140472. [PMID: 32553892 DOI: 10.1016/j.bbapap.2020.140472] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 05/27/2020] [Accepted: 06/10/2020] [Indexed: 12/15/2022]
Abstract
D-amino acids research field has recently gained an increased interest since these atypical molecules have been discovered to play a plethora of different roles. In the mammalian central nervous system, d-aspartate (D-Asp) is critically involved in the regulation of glutamatergic neurotransmission by acting as an agonist of NMDA receptor. Accordingly, alterations in its metabolism have been related to different pathologies. D-Asp shows a peculiar temporal pattern of emergence during ontogenesis and soon after birth its brain levels are strictly regulated by the catabolic enzyme d-aspartate oxidase (DASPO), a FAD-dependent oxidase. Rodents have been widely used as in vivo models for deciphering molecular mechanisms and for testing novel therapeutic targets and drugs, but human targets can significantly differ. Based on these considerations, here we investigated the structural and functional properties of the mouse DASPO, in particular kinetic properties, ligand and flavin binding, oligomerization state and protein stability. We compared the obtained findings with those of the human enzyme (80% sequence identity) highlighting a different oligomeric state and a lower activity for the mouse DASPO, which apoprotein species exists in solution in two forms differing in FAD affinity. The features that distinguish mouse and human DASPO suggest that this flavoenzyme might control in a distinct way the brain D-Asp levels in different organisms.
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Affiliation(s)
- Vincenzo Puggioni
- "The Protein Factory 2.0", Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy
| | - Antonio Savinelli
- "The Protein Factory 2.0", Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy
| | - Matteo Miceli
- "The Protein Factory 2.0", Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy
| | - Gianluca Molla
- "The Protein Factory 2.0", Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy
| | - Loredano Pollegioni
- "The Protein Factory 2.0", Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy; International Research Center on D-amino acids DAAIR, via Lepetit 34, 21040, Gerenzano (VA), Italy
| | - Silvia Sacchi
- "The Protein Factory 2.0", Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy; International Research Center on D-amino acids DAAIR, via Lepetit 34, 21040, Gerenzano (VA), Italy.
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30
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Molla G, Chaves‐Sanjuan A, Savinelli A, Nardini M, Pollegioni L. Structure and kinetic properties of humand‐aspartate oxidase, the enzyme‐controllingd‐aspartate levels in brain. FASEB J 2019; 34:1182-1197. [DOI: 10.1096/fj.201901703r] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 11/05/2019] [Accepted: 11/10/2019] [Indexed: 12/19/2022]
Affiliation(s)
- Gianluca Molla
- Dipartimento di Biotecnologie e Scienze della Vita Università degli studi dell’Insubria Varese Italy
| | | | - Antonio Savinelli
- Dipartimento di Biotecnologie e Scienze della Vita Università degli studi dell’Insubria Varese Italy
| | - Marco Nardini
- Dipartimento di Bioscienze Università degli studi di Milano Milano Italy
| | - Loredano Pollegioni
- Dipartimento di Biotecnologie e Scienze della Vita Università degli studi dell’Insubria Varese Italy
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31
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Murtas G, Sacchi S, Pollegioni L. Substitution of Arginine 120 in Human D-Amino Acid Oxidase Favors FAD-Binding and Nuclear Mistargeting. Front Mol Biosci 2019; 6:125. [PMID: 31799256 PMCID: PMC6862323 DOI: 10.3389/fmolb.2019.00125] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 10/28/2019] [Indexed: 01/23/2023] Open
Abstract
The peroxisomal enzyme human D-amino acid oxidase (hDAAO) is attracting attention owing to its role in degrading D-serine, the main co-agonist of N-methyl D-aspartate receptors in brain, and its involvement in brain functions and diseases. Here, we focused on arginine 120, a residue located at the protein interface, 20 Å from the assumed second ligand-binding site, showing a different orientation of the side chain in the hDAAO-benzoate complex, and corresponding to Ser119 in rat DAAO, which is part of a putative nuclear translocation signal (NTS). By substituting Arg120 in hDAAO with a glutamate (to mimic the active NTS) or a leucine (to eliminate the positive charge) the protein conformation, thermal stability, and kinetic properties are slightly altered, while the dimeric structure and the ligand-binding properties are unchanged. The most relevant alteration in Arg120 variants is the strongest interaction with FAD. Nevertheless, the activity assayed at low D-serine and FAD concentrations (resembling physiological conditions) was quite similar for wild-type and Arg120 hDAAO variants. These results resemble the ones obtained substituting another residue located at the interface region (i.e., the W209R variant), indicating that substitutions at the monomer-monomer interface mainly affects the FAD binding in hDAAO. Indeed, U87 glioblastoma cells transiently transfected for hDAAO variants show that substitution of Arg120 favors mistargeting: the increase in cytosolic localization observed for the variants promotes nuclear targeting, especially for the R120E hDAAO, without affecting cell viability. Notably, mistargeting to the nucleus is an innate process as it is apparent for the wild-type hDAAO, too: whether such a process is related to specific pathologic processes is still unknown.
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Affiliation(s)
- Giulia Murtas
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, Varese, Italy
| | - Silvia Sacchi
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, Varese, Italy
| | - Loredano Pollegioni
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, Varese, Italy
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32
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Effects of arsenic exposure on d-serine metabolism in the hippocampus of offspring mice at different developmental stages. Arch Toxicol 2019; 94:77-87. [DOI: 10.1007/s00204-019-02616-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 11/06/2019] [Indexed: 12/13/2022]
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33
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Mothet JP, Billard JM, Pollegioni L, Coyle JT, Sweedler JV. Investigating brain d-serine: Advocacy for good practices. Acta Physiol (Oxf) 2019; 226:e13257. [PMID: 30650253 PMCID: PMC6462235 DOI: 10.1111/apha.13257] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 01/09/2019] [Accepted: 01/10/2019] [Indexed: 12/31/2022]
Abstract
The last two decades have witnessed remarkable advance in our understanding the role of d-amino acids in the mammalian nervous system: from the unknown, to known molecules with unknown functions, to potential central players in health and disease. d-Amino acids have emerged as an important class of signaling molecules. In particular, the exploration of the roles of d-serine in brain physiopathology is a vibrant field that is growing at an accelerating pace. However, disentangling the functions of a chiral molecule in a complex chemical matrice as the brain requires specific measurement and detection methods but is also a challenging task as many molecular tools and models investigators are using can lead to confounded observations. Thus, study of d-amino acids demands accurate methodologies and specific controls, and these have often been lacking. Here we outline best practices for d-amino acid research, with a special emphasis on d-serine. We hope these concepts help move the field to greater rigor and reproducibility, allowing the field to advance.
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Affiliation(s)
- Jean-Pierre Mothet
- Team Gliotransmission & Synaptopathies, Aix Marseille University, Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille UMR7286 CNRS, Marseille, France
| | | | - Loredano Pollegioni
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell’Insubria, Varese, Italy
| | - Joseph T Coyle
- Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Jonathan V Sweedler
- Department of Chemistry and the Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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34
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Graham DL, Beio ML, Nelson DL, Berkowitz DB. Human Serine Racemase: Key Residues/Active Site Motifs and Their Relation to Enzyme Function. Front Mol Biosci 2019; 6:8. [PMID: 30918891 PMCID: PMC6424897 DOI: 10.3389/fmolb.2019.00008] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 02/12/2019] [Indexed: 01/06/2023] Open
Abstract
Serine racemase (SR) is the first racemase enzyme to be identified in human biology and converts L-serine to D-serine, an important neuronal signaling molecule that serves as a co-agonist of the NMDA (N-methyl-D-aspartate) receptor. This overview describes key molecular features of the enzyme, focusing on the side chains and binding motifs that control PLP (pyridoxal phosphate) cofactor binding as well as activity modulation through the binding of both divalent cations and ATP, the latter showing allosteric modulation. Discussed are catalytically important residues in the active site including K56 and S84—the si- and re-face bases, respectively,—and R135, a residue that appears to play a critical role in the binding of both negatively charged alternative substrates and inhibitors. The interesting bifurcated mechanism followed by this enzyme whereby substrate L-serine can be channeled either into D-serine (racemization pathway) or into pyruvate (β-elimination pathway) is discussed extensively, as are studies that focus on a key loop region (the so-called “triple serine loop”), the modification of which can be used to invert the normal in vitro preference of this enzyme for the latter pathway over the former. The possible cross-talk between the PLP enzymes hSR and hCBS (human cystathionine β-synthase) is discussed, as the former produces D-serine and the latter produces H2S, both of which stimulate the NMDAR and both of which have been implicated in neuronal infarction pursuant to ischemic stroke. Efforts to gain a more complete mechanistic understanding of these PLP enzymes are expected to provide valuable insights for the development of specific small molecule modulators of these enzymes as tools to study their roles in neuronal signaling and in modulation of NMDAR function.
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Affiliation(s)
- Danielle L Graham
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE, United States
| | - Matthew L Beio
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE, United States
| | - David L Nelson
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE, United States
| | - David B Berkowitz
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE, United States
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35
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Pollegioni L, Sacchi S, Murtas G. Human D-Amino Acid Oxidase: Structure, Function, and Regulation. Front Mol Biosci 2018; 5:107. [PMID: 30547037 PMCID: PMC6279847 DOI: 10.3389/fmolb.2018.00107] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 11/12/2018] [Indexed: 12/11/2022] Open
Abstract
D-Amino acid oxidase (DAAO) is an FAD-containing flavoenzyme that catalyzes with absolute stereoselectivity the oxidative deamination of all natural D-amino acids, the only exception being the acidic ones. This flavoenzyme plays different roles during evolution and in different tissues in humans. Its three-dimensional structure is well conserved during evolution: minute changes are responsible for the functional differences between enzymes from microorganism sources and those from humans. In recent years several investigations focused on human DAAO, mainly because of its role in degrading the neuromodulator D-serine in the central nervous system. D-Serine is the main coagonist of N-methyl D-aspartate receptors, i.e., excitatory amino acid receptors critically involved in main brain functions and pathologic conditions. Human DAAO possesses a weak interaction with the FAD cofactor; thus, in vivo it should be largely present in the inactive, apoprotein form. Binding of active-site ligands and the substrate stabilizes flavin binding, thus pushing the acquisition of catalytic competence. Interestingly, the kinetic efficiency of the enzyme on D-serine is very low. Human DAAO interacts with various proteins, in this way modulating its activity, targeting, and cell stability. The known properties of human DAAO suggest that its activity must be finely tuned to fulfill a main physiological function such as the control of D-serine levels in the brain. At present, studies are focusing on the epigenetic modulation of human DAAO expression and the role of post-translational modifications on its main biochemical properties at the cellular level.
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Affiliation(s)
- Loredano Pollegioni
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, Varese, Italy
| | - Silvia Sacchi
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, Varese, Italy
| | - Giulia Murtas
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, Varese, Italy
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Billard JM. Changes in Serine Racemase-Dependent Modulation of NMDA Receptor: Impact on Physiological and Pathological Brain Aging. Front Mol Biosci 2018; 5:106. [PMID: 30555832 PMCID: PMC6282039 DOI: 10.3389/fmolb.2018.00106] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 11/09/2018] [Indexed: 02/02/2023] Open
Abstract
The N-methyl-D-Aspartate glutamate receptors (NMDARs) are pivotal for the functional and morphological plasticity that are required in neuronal networks for efficient brain activities and notably for cognitive-related abilities. Because NMDARs are heterogeneous in subunit composition and associated with multiple functional regulatory sites, their efficacy is under the tonic influence of numerous allosteric modulations, whose dysfunction generally represents the first step generating pathological states. Among the enzymatic candidates, serine racemase (SR) has recently gathered an increasing interest considering that it tightly regulates the production of d-serine, an amino acid now viewed as the main endogenous co-agonist necessary for NMDAR activation. Nowadays, SR deregulation is associated with a wide range of neurological and psychiatric diseases including schizophrenia, amyotrophic lateral sclerosis, and depression. This review aims at compelling the most recent experimental evidences indicating that changes in SR-related modulation of NMDARs also govern opposite functional dysfunctions in physiological and pathological (Alzheimer's disease) aging that finally results in memory disabilities in both cases. It also highlights SR as a relevant alternative target for new pharmacological strategies aimed at preventing functional alterations and cognitive impairments linked to the aging process.
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Billard JM, Freret T. Asc-1 transporter activation: an alternative to rescue age-related alterations in functional plasticity at rat hippocampal CA3/CA1 synapses. J Neurochem 2018; 147:514-525. [DOI: 10.1111/jnc.14586] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 08/23/2018] [Accepted: 08/25/2018] [Indexed: 11/29/2022]
Affiliation(s)
- Jean-Marie Billard
- Centre de Psychiatrie et Neurosciences; Université Paris Descartes; Sorbonne Paris Cité; UMR 894; Paris France
- Normandie Univ.; UNICAEN; INSERM; COMETE; Caen France
| | - Thomas Freret
- Normandie Univ.; UNICAEN; INSERM; COMETE; Caen France
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Neuronal serine racemase associates with Disrupted-In-Schizophrenia-1 and DISC1 agglomerates: Implications for schizophrenia. Neurosci Lett 2018; 692:107-114. [PMID: 30391323 DOI: 10.1016/j.neulet.2018.10.055] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 10/18/2018] [Accepted: 10/29/2018] [Indexed: 12/21/2022]
Abstract
D-Serine, an endogenous coagonist of N-methyl-d-aspartate receptors (NMDARs) at the glycine binding site, is synthesized by serine racemase (SR) through conversion of l-Serine. Dysregulation of SR/D-Serine and Disrupted-In-Schizophrenia-1 (DISC1) contributes to the pathogenesis of schizophrenia at converging pathways, as perturbation of SR-DISC1 binding in astrocytes elicits schizophrenia-like behaviors in mice. However, an association of neuronal SR with DISC1 remains elusive. Here we report that SR associates with DISC1 and its agglomerates in cortical neurons, which can be modulated by NMDAR activity. Endogenous SR colocalizes with DISC1 large agglomerates in the soma and with smaller puncta in the nucleus and dendrites of cortical neurons. Co-immunoprecipitation assays demonstrate SR interaction with DISC1 in cortical neuronal lysates, suggesting the physiological presence of functional SR-DISC1 complexes in neurons. Moreover, exogenous d-Serine application significantly increases the interaction of SR with DISC1, the number of DISC1-SR large agglomerates and the levels of DISC1 agglomerated form along with SR in the triton-insoluble pellet fraction, whereas application of glycine with a glycine transporter inhibitor fails to increase their interactions, abundance of DISC1-SR large agglomerates and levels of DISC1 agglomerated form. This increase by d-Serine application is blocked by 7-chlorokynurenic acid, a specific antagonist at the glycine site of NMDARs, suggesting mediation through NMDARs. Our findings thus demonstrate neuronal SR association with DISC1 and its agglomerates, which can be modulated by d-Serine, thereby validating a novel neuronal SR-DISC1 complex responsive to NMDAR activation and providing a molecular mechanism by which pathways implicated in schizophrenia converge.
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Impact of Aging in Microglia-Mediated D-Serine Balance in the CNS. Mediators Inflamm 2018; 2018:7219732. [PMID: 30363571 PMCID: PMC6180939 DOI: 10.1155/2018/7219732] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Revised: 08/19/2018] [Accepted: 08/30/2018] [Indexed: 01/12/2023] Open
Abstract
A mild chronic inflammatory state, like that observed in aged individuals, affects microglial function, inducing a dysfunctional phenotype that potentiates neuroinflammation and cytotoxicity instead of neuroprotection in response to additional challenges. Given that inflammatory activation of microglia promotes increased release of D-serine, we postulate that age-dependent inflammatory brain environment leads to microglia-mediated changes on the D-serine-regulated glutamatergic transmission. Furthermore, D-serine dysregulation, in addition to affecting synaptogenesis and synaptic plasticity, appears also to potentiate NMDAR-dependent excitotoxicity, promoting neurodegeneration and cognitive impairment. D-serine dysregulation promoted by microglia could have a role in age-related cognitive impairment and in the induction and progression of neurodegenerative processes like Alzheimer's disease.
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Sacchi S, Cappelletti P, Murtas G. Biochemical Properties of Human D-amino Acid Oxidase Variants and Their Potential Significance in Pathologies. Front Mol Biosci 2018; 5:55. [PMID: 29946548 PMCID: PMC6005901 DOI: 10.3389/fmolb.2018.00055] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 05/23/2018] [Indexed: 12/11/2022] Open
Abstract
The stereoselective flavoenzyme D-amino acid oxidase (DAAO) catalyzes the oxidative deamination of neutral and polar D-amino acids producing the corresponding α-keto acids, ammonia, and hydrogen peroxide. Despite its peculiar and atypical substrates, DAAO is widespread expressed in most eukaryotic organisms. In mammals (and humans in particular), DAAO is involved in relevant physiological processes ranging from D-amino acid detoxification in kidney to neurotransmission in the central nervous system, where DAAO is responsible of the catabolism of D-serine, a key endogenous co-agonist of N-methyl-D-aspartate receptors. Recently, structural and functional studies have brought to the fore the distinctive biochemical properties of human DAAO (hDAAO). It appears to have evolved to allow a strict regulation of its activity, so that the enzyme can finely control the concentration of substrates (such as D-serine in the brain) without yielding to an excessive production of hydrogen peroxide, a potentially toxic reactive oxygen species (ROS). Indeed, dysregulation in D-serine metabolism, likely resulting from altered levels of hDAAO expression and activity, has been implicated in several pathologies, ranging from renal disease to neurological, neurodegenerative, and psychiatric disorders. Only one mutation in DAO gene was unequivocally associated to a human disease. However, several single nucleotide polymorphisms (SNPs) are reported in the database and the biochemical characterization of the corresponding recombinant hDAAO variants is of great interest for investigating the effect of mutations. Here we reviewed recently published data focusing on the modifications of the structural and functional properties induced by amino acid substitutions encoded by confirmed SNPs and on their effect on D-serine cellular levels. The potential significance of the different hDAAO variants in human pathologies will be also discussed.
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Affiliation(s)
- Silvia Sacchi
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, Varese, Italy.,The Protein Factory, Politecnico di Milano and Università degli Studi dell'Insubria, Milan, Italy
| | - Pamela Cappelletti
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, Varese, Italy.,The Protein Factory, Politecnico di Milano and Università degli Studi dell'Insubria, Milan, Italy
| | - Giulia Murtas
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, Varese, Italy
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Distinctive Roles of D-Amino Acids in the Homochiral World: Chirality of Amino Acids Modulates Mammalian Physiology and Pathology. Keio J Med 2018; 68:1-16. [PMID: 29794368 DOI: 10.2302/kjm.2018-0001-ir] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Living organisms enantioselectively employ L-amino acids as the molecular architecture of protein synthesized in the ribosome. Although L-amino acids are dominantly utilized in most biological processes, accumulating evidence points to the distinctive roles of D-amino acids in non-ribosomal physiology. Among the three domains of life, bacteria have the greatest capacity to produce a wide variety of D-amino acids. In contrast, archaea and eukaryotes are thought generally to synthesize only two kinds of D-amino acids: D-serine and D-aspartate. In mammals, D-serine is critical for neurotransmission as an endogenous coagonist of N-methyl D-aspartate receptors. Additionally, D-aspartate is associated with neurogenesis and endocrine systems. Furthermore, recognition of D-amino acids originating in bacteria is linked to systemic and mucosal innate immunity. Among the roles played by D-amino acids in human pathology, the dysfunction of neurotransmission mediated by D-serine is implicated in psychiatric and neurological disorders. Non-enzymatic conversion of L-aspartate or L-serine residues to their D-configurations is involved in age-associated protein degeneration. Moreover, the measurement of plasma or urinary D-/L-serine or D-/L-aspartate levels may have diagnostic or prognostic value in the treatment of kidney diseases. This review aims to summarize current understanding of D-amino-acid-associated biology with a major focus on mammalian physiology and pathology.
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Murtas G, Caldinelli L, Cappelletti P, Sacchi S, Pollegioni L. Human d-amino acid oxidase: The inactive G183R variant. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1866:822-830. [PMID: 29274788 DOI: 10.1016/j.bbapap.2017.12.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 12/12/2017] [Accepted: 12/14/2017] [Indexed: 12/11/2022]
Abstract
In the brain, the enzyme d-amino acid oxidase (DAAO) catalyzes the oxidative deamination of d-serine, a main positive modulator of the N-methyl-d-aspartate subtype of glutamate receptors (NMDAR). Dysregulation in d-serine signaling is implicated in the NMDAR dysfunctions observed in various brain diseases, such as amyotrophic lateral sclerosis, Alzheimer's disease, schizophrenia. A strain of ddY mice lacking DAAO activity due to the G181R substitution (DAAOG181R mice) and exhibiting increased d-serine concentration as compared to wild-type mice shows altered pain response, improved adaptative learning and cognitive functions, and larger hippocampal long-term potentiation. In past years, this mice line has been used to shed light on physiological and pathological brain functions related to NMDAR. Here, we decided to introduce the corresponding substitution in human DAAO (hDAAO). The recombinant G183R hDAAO is produced as an inactive apoprotein: the substitution alters the protein conformation that negatively affects the ability to bind the flavin cofactor in the orientation required for hydride-transfer during catalysis. At the cellular level, the overexpressed G183R hDAAO is not fully targeted to peroxisomes, forms protein aggregates showing a strong colocalization with ubiquitin, and significantly (7-fold) increases both the d-serine cellular concentration and the D/(D+L)-serine ratio. Taken together, our investigation warrants caution in using DAAOG181R mice: the abolition of enzymatic activity is coupled to DAAO aggregation, a central process in different pathological conditions. The effect due to G181R substitution in DAAO could be misleading: the effects due to impairment of d-serine degradation overlap with those related to aggregates accumulation.
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Affiliation(s)
- Giulia Murtas
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy.
| | - Laura Caldinelli
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy; The Protein Factory, Politecnico di Milano and Università degli studi dell'Insubria, via Mancinelli 7, 20131 Milan, Italy
| | - Pamela Cappelletti
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy; The Protein Factory, Politecnico di Milano and Università degli studi dell'Insubria, via Mancinelli 7, 20131 Milan, Italy
| | - Silvia Sacchi
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy; The Protein Factory, Politecnico di Milano and Università degli studi dell'Insubria, via Mancinelli 7, 20131 Milan, Italy
| | - Loredano Pollegioni
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy; The Protein Factory, Politecnico di Milano and Università degli studi dell'Insubria, via Mancinelli 7, 20131 Milan, Italy
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Beltrán-Castillo S, Olivares MJ, Contreras RA, Zúñiga G, Llona I, von Bernhardi R, Eugenín JL. D-serine released by astrocytes in brainstem regulates breathing response to CO 2 levels. Nat Commun 2017; 8:838. [PMID: 29018191 PMCID: PMC5635109 DOI: 10.1038/s41467-017-00960-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 08/09/2017] [Indexed: 11/17/2022] Open
Abstract
Central chemoreception is essential for adjusting breathing to physiological demands, and for maintaining CO2 and pH homeostasis in the brain. CO2-induced ATP release from brainstem astrocytes stimulates breathing. NMDA receptor (NMDAR) antagonism reduces the CO2-induced hyperventilation by unknown mechanisms. Here we show that astrocytes in the mouse caudal medullary brainstem can synthesize, store, and release d-serine, an agonist for the glycine-binding site of the NMDAR, in response to elevated CO2 levels. We show that systemic and raphe nucleus d-serine administration to awake, unrestrained mice increases the respiratory frequency. Application of d-serine to brainstem slices also increases respiratory frequency, which was prevented by NMDAR blockade. Inhibition of d-serine synthesis, enzymatic degradation of d-serine, or the sodium fluoroacetate-induced impairment of astrocyte functions decrease the basal respiratory frequency and the CO2-induced respiratory response in vivo and in vitro. Our findings suggest that astrocytic release of d-serine may account for the glutamatergic contribution to central chemoreception. Astrocytes are involved in chemoreception in brainstem areas that regulate breathing rhythm, and astrocytes are known to release d-serine. Here the authors show that astrocyte release of d-serine contributes to CO2 sensing and breathing in brainstem slices, and in vivo in awake unrestrained mice.
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Affiliation(s)
- S Beltrán-Castillo
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Santiago, 9170022, Chile
| | - M J Olivares
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Santiago, 9170022, Chile
| | - R A Contreras
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Santiago, 9170022, Chile
| | - G Zúñiga
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Santiago, 9170022, Chile
| | - I Llona
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Santiago, 9170022, Chile
| | - R von Bernhardi
- Departamento de Neurología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, 8330024, Chile.
| | - J L Eugenín
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Santiago, 9170022, Chile.
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Santos CL, Roppa PHA, Truccolo P, Fontella FU, Souza DO, Bobermin LD, Quincozes-Santos A. Age-Dependent Neurochemical Remodeling of Hypothalamic Astrocytes. Mol Neurobiol 2017; 55:5565-5579. [PMID: 28980158 DOI: 10.1007/s12035-017-0786-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 09/21/2017] [Indexed: 01/18/2023]
Abstract
The hypothalamus is a crucial integrative center in the central nervous system, responsible for the regulation of homeostatic activities, including systemic energy balance. Increasing evidence has highlighted a critical role of astrocytes in orchestrating hypothalamic functions; they participate in the modulation of synaptic transmission, metabolic and trophic support to neurons, immune defense, and nutrient sensing. In this context, disturbance of systemic energy homeostasis, which is a common feature of obesity and the aging process, involves inflammatory responses. This may be related to dysfunction of hypothalamic astrocytes. In this regard, the aim of this study was to evaluate the neurochemical properties of hypothalamic astrocyte cultures from newborn, adult, and aged Wistar rats. Age-dependent changes in the regulation of glutamatergic homeostasis, glutathione biosynthesis, amino acid profile, glucose metabolism, trophic support, and inflammatory response were observed. Additionally, signaling pathways including nuclear factor erythroid-derived 2-like 2/heme oxygenase-1 p38 mitogen-activated protein kinase, nuclear factor kappa B, phosphatidylinositide 3-kinase/Akt, and leptin receptor expression may represent putative mechanisms associated with the cellular alterations. In summary, our findings indicate that as age increases, hypothalamic astrocytes remodel and exhibit changes in their neurochemical properties. This process may play a role in the onset and/or progression of metabolic disorders.
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Affiliation(s)
- Camila Leite Santos
- Departamento de Bioquímica, Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Bairro Santa Cecília, Porto Alegre, RS, 90035-003, Brazil
| | - Paola Haack Amaral Roppa
- Departamento de Bioquímica, Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Bairro Santa Cecília, Porto Alegre, RS, 90035-003, Brazil
| | - Pedro Truccolo
- Departamento de Bioquímica, Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Bairro Santa Cecília, Porto Alegre, RS, 90035-003, Brazil
| | - Fernanda Urruth Fontella
- Departamento de Bioquímica, Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Bairro Santa Cecília, Porto Alegre, RS, 90035-003, Brazil
| | - Diogo Onofre Souza
- Departamento de Bioquímica, Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Bairro Santa Cecília, Porto Alegre, RS, 90035-003, Brazil
| | - Larissa Daniele Bobermin
- Departamento de Bioquímica, Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Bairro Santa Cecília, Porto Alegre, RS, 90035-003, Brazil.
| | - André Quincozes-Santos
- Departamento de Bioquímica, Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Bairro Santa Cecília, Porto Alegre, RS, 90035-003, Brazil.
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Wu J, Zhao R, Guo L, Zhen X. Morphine-induced inhibition of Ca 2+ -dependent d-serine release from astrocytes suppresses excitability of GABAergic neurons in the nucleus accumbens. Addict Biol 2017; 22:1289-1303. [PMID: 27239019 DOI: 10.1111/adb.12417] [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] [Received: 09/16/2015] [Revised: 05/04/2016] [Accepted: 05/11/2016] [Indexed: 12/20/2022]
Abstract
The nucleus accumbens (NAc) plays a critical role in addictive drug-induced behavioral changes. d-serine is present at high levels in the brain and is involved in the regulation of N-methyl-d-aspartate glutamate (NMDA)-dependent synaptic activity. In this study, we aimed to examine the involvement of d-serine in morphine addiction. Morphine decreased the NMDA receptor-mediated excitatory postsynaptic currents and excitability of GABAergic neurons in the NAc, while exogenous d-serine alleviated the effects of morphine. Morphine reduced extracellular d-serine levels in rat NAc or in primary culture of astrocytes through inhibition of intracellular Ca2+ signals and blockade of d-serine release from cell vesicles. Morphine induced robust internalization of α-amino-3-hydroxy-5-methyl-4-isoxazole-propionate acid receptor (AMPAR) in primary cultured astrocytes. Moreover, administration of exogenous d-serine to rats inhibited the development of locomotor sensitization to morphine, attenuated the morphine-induced potentiation on conditioned place preference and suppressed the morphine-enhanced expression of p-CREB and ΔFosB in the NAc. Overall, our results showed that morphine inhibited d-serine release from astrocytes through modulation of AMPAR-mediated Ca2+ influx, and led to the inhibition of postsynaptic excitability of GABAergic neurons in the NAc. This work may provide a new insight into the underlying mechanisms of morphine addiction.
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Affiliation(s)
- Jian Wu
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuropsychiatric Disorders and The Collaborative Innovation Center for Brain Sciences, College of Pharmaceutical Sciences; Soochow University; China
- College of Medicine; Nantong University; China
| | - Rui Zhao
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuropsychiatric Disorders and The Collaborative Innovation Center for Brain Sciences, College of Pharmaceutical Sciences; Soochow University; China
| | - Lin Guo
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuropsychiatric Disorders and The Collaborative Innovation Center for Brain Sciences, College of Pharmaceutical Sciences; Soochow University; China
| | - Xuechu Zhen
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuropsychiatric Disorders and The Collaborative Innovation Center for Brain Sciences, College of Pharmaceutical Sciences; Soochow University; China
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Wang J, Zhang K, Chen X, Liu X, Teng H, Zhao M, Sun Z. Epigenetic Activation of ASCT2 in the Hippocampus Contributes to Depression-Like Behavior by Regulating D-Serine in Mice. Front Mol Neurosci 2017; 10:139. [PMID: 28536503 PMCID: PMC5422558 DOI: 10.3389/fnmol.2017.00139] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Accepted: 04/21/2017] [Indexed: 11/28/2022] Open
Abstract
The roles of D-serine in depression are raised concerned recently as an intrinsic co-agonist for the NMDA receptor. However, the mechanisms underlying its regulation are not fully elucidated. ASCT2 is a Na+-dependent D-serine transporter. We found that decreased D-serine and increased hippocampal ASCT2 levels correlated with chronic social defeat stress (CSDS) in mice. Lentivirus-mediated shRNA-mediated knockdown of ASCT2 and the administration of exogenous D-serine in the hippocampus alleviated CSDS-induced social avoidance and immobility. In vivo and in vitro experiments revealed that upregulation of ASCT2 expression in CSDS was regulated through histone hyper-acetylation, not DNA methylation in its promoter region. Immunohistochemistry demonstrated the co-localization of ASCT2 and D-serine. Uptake of D-serine by ASCT2 was demonstrated by in vivo and in vitro experiments. Our results indicate that CSDS induces ASCT2 expression through epigenetic activation and decreases hippocampal D-serine levels, leading to social avoidance, and immobility. Thus, targeting D-serine transport represents an attractive new strategy for treating depression.
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Affiliation(s)
- Jiesi Wang
- Beijing Institutes of Life Science, Chinese Academy of SciencesBeijing, China.,Key Lab of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China.,University of Chinese Academy of SciencesBeijing, China
| | - Ke Zhang
- Key Lab of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China.,University of Chinese Academy of SciencesBeijing, China
| | - Xiaojuan Chen
- Key Lab of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China.,University of Chinese Academy of SciencesBeijing, China
| | - Xiaoqian Liu
- Key Lab of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China
| | - Huajing Teng
- Beijing Institutes of Life Science, Chinese Academy of SciencesBeijing, China
| | - Mei Zhao
- Key Lab of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China.,University of Chinese Academy of SciencesBeijing, China
| | - Zhongsheng Sun
- Beijing Institutes of Life Science, Chinese Academy of SciencesBeijing, China.,Key Lab of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China.,Institute of Genomic Medicine, Wenzhou Medical CollegeWenzhou, China
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Acton D, Miles GB. Differential regulation of NMDA receptors by d-serine and glycine in mammalian spinal locomotor networks. J Neurophysiol 2017; 117:1877-1893. [PMID: 28202572 PMCID: PMC5411468 DOI: 10.1152/jn.00810.2016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 01/11/2017] [Accepted: 02/11/2017] [Indexed: 12/11/2022] Open
Abstract
We provide evidence that NMDARs within murine spinal locomotor networks determine the frequency and amplitude of ongoing locomotor-related activity in vitro and that NMDARs are regulated by d-serine and glycine in a synapse-specific and activity-dependent manner. In addition, glycine transporter-1 is shown to be an important regulator of NMDARs during locomotor-related activity. These results show how excitatory transmission can be tuned to diversify the output repertoire of spinal locomotor networks in mammals. Activation of N-methyl-d-aspartate receptors (NMDARs) requires the binding of a coagonist, either d-serine or glycine, in addition to glutamate. Changes in occupancy of the coagonist binding site are proposed to modulate neural networks including those controlling swimming in frog tadpoles. Here, we characterize regulation of the NMDAR coagonist binding site in mammalian spinal locomotor networks. Blockade of NMDARs by d(−)-2-amino-5-phosphonopentanoic acid (d-APV) or 5,7-dichlorokynurenic acid reduced the frequency and amplitude of pharmacologically induced locomotor-related activity recorded from the ventral roots of spinal-cord preparations from neonatal mice. Furthermore, d-APV abolished synchronous activity induced by blockade of inhibitory transmission. These results demonstrate an important role for NMDARs in murine locomotor networks. Bath-applied d-serine enhanced the frequency of locomotor-related but not disinhibited bursting, indicating that coagonist binding sites are saturated during the latter but not the former mode of activity. Depletion of endogenous d-serine by d-amino acid oxidase or the serine-racemase inhibitor erythro-β-hydroxy-l-aspartic acid (HOAsp) increased the frequency of locomotor-related activity, whereas application of l-serine to enhance endogenous d-serine synthesis reduced burst frequency, suggesting a requirement for d-serine at a subset of synapses onto inhibitory interneurons. Consistent with this, HOAsp was ineffective during disinhibited activity. Bath-applied glycine (1–100 µM) failed to alter locomotor-related activity, whereas ALX 5407, a selective inhibitor of glycine transporter-1 (GlyT1), enhanced burst frequency, supporting a role for GlyT1 in NMDAR regulation. Together these findings indicate activity-dependent and synapse-specific regulation of the coagonist binding site within spinal locomotor networks, illustrating the importance of NMDAR regulation in shaping motor output. NEW & NOTEWORTHY We provide evidence that NMDARs within murine spinal locomotor networks determine the frequency and amplitude of ongoing locomotor-related activity in vitro and that NMDARs are regulated by d-serine and glycine in a synapse-specific and activity-dependent manner. In addition, glycine transporter-1 is shown to be an important regulator of NMDARs during locomotor-related activity. These results show how excitatory transmission can be tuned to diversify the output repertoire of spinal locomotor networks in mammals.
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Affiliation(s)
- David Acton
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, Fife, United Kingdom
| | - Gareth B Miles
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, Fife, United Kingdom
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Fujita Y, Ishima T, Hashimoto K. Supplementation with D-serine prevents the onset of cognitive deficits in adult offspring after maternal immune activation. Sci Rep 2016; 6:37261. [PMID: 27853241 PMCID: PMC5112512 DOI: 10.1038/srep37261] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 10/26/2016] [Indexed: 12/26/2022] Open
Abstract
Prenatal maternal infection contributes to the etiology of schizophrenia, with D-serine, an endogenous co-agonist of the N-methyl-D-aspartate (NMDA) receptor, playing a role in the pathophysiology of this disease. We examined whether supplementation with D-serine during juvenile and adolescent stages could prevent the onset of cognitive deficits, prodromal and the core symptoms of schizophrenia in adult offspring after maternal immune activation (MIA). Juvenile offspring exposed prenatally to poly(I:C) showed reduced expression of NMDA receptor subunits in the hippocampus. Supplementing drinking water with D-serine (600 mg/L from P28 to P56) prevented the onset of cognitive deficits in adult offspring after MIA, in a significant manner. This study shows that supplementing offspring with D-serine during juvenile and adolescent stages could prevent the onset of psychosis in adulthood, after MIA. Therefore, early intervention with D-serine may prevent the occurrence of psychosis in high-risk subjects.
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Affiliation(s)
- Yuko Fujita
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba 260-8670, Japan
| | - Tamaki Ishima
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba 260-8670, Japan
| | - Kenji Hashimoto
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba 260-8670, Japan
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Xia M, Abazyan S, Jouroukhin Y, Pletnikov M. Behavioral sequelae of astrocyte dysfunction: focus on animal models of schizophrenia. Schizophr Res 2016; 176:72-82. [PMID: 25468180 PMCID: PMC4439390 DOI: 10.1016/j.schres.2014.10.044] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 10/29/2014] [Accepted: 10/31/2014] [Indexed: 12/12/2022]
Abstract
Astrocytes regulate multiple processes in the brain ranging from trophic support of developing neurons to modulation of synaptic neurotransmission and neuroinflammation in adulthood. It is, therefore, understandable that pathogenesis and pathophysiology of major psychiatric disorders involve astrocyte dysfunctions. Until recently, there has been the paucity of experimental approaches to studying the roles of astrocytes in behavioral disease. A new generation of in vivo models allows us to advance our understanding of the roles of astrocytes in psychiatric disorders. This review will evaluate the recent studies that focus on the contribution of astrocyte dysfunction to behavioral alterations pertinent to schizophrenia and will propose the possible solutions of the limitations of the existing approaches.
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Affiliation(s)
- Meng Xia
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine,Preclinical College, Guangxi University of Chinese Medicine, Nanning, 530001, Guangxi Province, China,Chinese Medicine College, Hubei University for Nationalities, ENSHI, 445000, Hubei Province, China
| | - Sofya Abazyan
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine
| | - Yan Jouroukhin
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine
| | - Mikhail Pletnikov
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, United States; Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, United States; Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, United States; Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, United States.
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