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Li YX, Yang JY, Alcantara M, Abelian G, Kulkarni A, Staubli U, Foster AC. Inhibitors of the Neutral Amino Acid Transporters ASCT1 and ASCT2 Are Effective in In Vivo Models of Schizophrenia and Visual Dysfunction. J Pharmacol Exp Ther 2018; 367:292-301. [DOI: 10.1124/jpet.118.251116] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 08/27/2018] [Indexed: 01/01/2023] Open
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2
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Schweimer JV, Coullon GSL, Betts JF, Burnet PWJ, Engle SJ, Brandon NJ, Harrison PJ, Sharp T. Increased burst-firing of ventral tegmental area dopaminergic neurons in D-amino acid oxidase knockout mice in vivo. Eur J Neurosci 2014; 40:2999-3009. [PMID: 25040393 DOI: 10.1111/ejn.12667] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 05/19/2014] [Accepted: 06/10/2014] [Indexed: 01/19/2023]
Abstract
d-Amino acid oxidase (DAO) degrades the N-methyl-d-aspartate (NMDA) receptor co-agonist d-serine, and is implicated in schizophrenia as a risk gene and therapeutic target. In schizophrenia, the critical neurochemical abnormality affects dopamine, but to date there is little evidence that DAO impacts on the dopamine system. To address this issue, we measured the electrophysiological properties of dopaminergic (DA) and non-DA neurons in the ventral tegmental area (VTA) of anaesthetised DAO knockout (DAO(-/-) ) and DAO heterozygote (DAO(+/-) ) mice as compared with their wild-type (DAO(+/+) ) littermates. Genotype was confirmed at the protein level by western blotting and immunohistochemistry. One hundred and thirty-nine VTA neurons were recorded in total, and juxtacellular labelling of a subset revealed that neurons immunopositive for tyrosine hydroxylase had DA-like electrophysiological properties that were distinct from those of neurons that were tyrosine hydroxylase-immunonegative. In DAO(-/-) mice, approximately twice as many DA-like neurons fired in a bursting pattern than in DAO(+/-) or DAO(+/+) mice, but other electrophysiological properties did not differ between genotypes. In contrast, non-DA-like neurons had a lower firing rate in DAO(-/-) mice than in DAO(+/-) or DAO(+/+) mice. These data provide the first direct evidence that DAO modulates VTA DA neuron activity, which is of interest for understanding both the glutamatergic regulation of dopamine function and the therapeutic potential of DAO inhibitors. The increased DA neuron burst-firing probably reflects increased availability of d-serine at VTA NMDA receptors, but the site, mechanism and mediation of the effect requires further investigation, and may include both direct and indirect processes.
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Affiliation(s)
- Judith V Schweimer
- University Department of Pharmacology, Mansfield Road, Oxford, OX1 3QT, UK; University Department of Psychiatry, Warneford Hospital, Oxford, OX3 7JX, UK
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Betts JF, Schweimer JV, Burnham KE, Burnet PWJ, Sharp T, Harrison PJ. D-amino acid oxidase is expressed in the ventral tegmental area and modulates cortical dopamine. Front Synaptic Neurosci 2014; 6:11. [PMID: 24822045 PMCID: PMC4014674 DOI: 10.3389/fnsyn.2014.00011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 04/09/2014] [Indexed: 12/11/2022] Open
Abstract
D-amino acid oxidase (DAO, DAAO) degrades the NMDA receptor co-agonist D-serine, modulating D-serine levels and thence NMDA receptor function. DAO inhibitors are under development as a therapy for schizophrenia, a disorder involving both NMDA receptor and dopaminergic dysfunction. However, a direct role for DAO in dopamine regulation has not been demonstrated. Here, we address this question in two ways. First, using in situ hybridization and immunohistochemistry, we show that DAO mRNA and immunoreactivity are present in the ventral tegmental area (VTA) of the rat, in tyrosine hydroxylase (TH)-positive and -negative neurons, and in glial fibrillary acidic protein (GFAP)-immunoreactive astrocytes. Second, we show that injection into the VTA of sodium benzoate, a DAO inhibitor, increases frontal cortex extracellular dopamine, as measured by in vivo microdialysis and high performance liquid chromatography. Combining sodium benzoate and D-serine did not enhance this effect, and injection of D-serine alone affected dopamine metabolites but not dopamine. These data show that DAO is expressed in the VTA, and suggest that it impacts on the mesocortical dopamine system. The mechanism by which the observed effects occur, and the implications of these findings for schizophrenia therapy, require further study.
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Affiliation(s)
- Jill F Betts
- Department of Psychiatry, University of Oxford Oxford, UK ; Department of Pharmacology, University of Oxford Oxford, UK
| | - Judith V Schweimer
- Department of Psychiatry, University of Oxford Oxford, UK ; Department of Pharmacology, University of Oxford Oxford, UK
| | - Katherine E Burnham
- Department of Psychiatry, University of Oxford Oxford, UK ; Department of Pharmacology, University of Oxford Oxford, UK
| | | | - Trevor Sharp
- Department of Pharmacology, University of Oxford Oxford, UK
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Levo-tetrahydropalmatine attenuates the development and expression of methamphetamine-induced locomotor sensitization and the accompanying activation of ERK in the nucleus accumbens and caudate putamen in mice. Neuroscience 2014; 258:101-10. [DOI: 10.1016/j.neuroscience.2013.11.025] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 10/24/2013] [Accepted: 11/12/2013] [Indexed: 11/20/2022]
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Repetitive behavior profile and supersensitivity to amphetamine in the C58/J mouse model of autism. Behav Brain Res 2013; 259:200-14. [PMID: 24211371 DOI: 10.1016/j.bbr.2013.10.052] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Revised: 10/27/2013] [Accepted: 10/31/2013] [Indexed: 12/29/2022]
Abstract
Restricted repetitive behaviors are core symptoms of autism spectrum disorders (ASDs). The range of symptoms encompassed by the repetitive behavior domain includes lower-order stereotypy and self-injury, and higher-order indices of circumscribed interests and cognitive rigidity. Heterogeneity in clinical ASD profiles suggests that specific manifestations of repetitive behavior reflect differential neuropathology. The present studies utilized a set of phenotyping tasks to determine a repetitive behavior profile for the C58/J mouse strain, a model of ASD core symptoms. In an observational screen, C58/J demonstrated overt motor stereotypy, but not over-grooming, a commonly-used measure for mouse repetitive behavior. Amphetamine did not exacerbate motor stereotypy, but had enhanced stimulant effects on locomotion and rearing in C58/J, compared to C57BL/6J. Both C58/J and Grin1 knockdown mice, another model of ASD-like behavior, had marked deficits in marble-burying. In a nose poke task for higher-order repetitive behavior, C58/J had reduced holeboard exploration and preference for non-social, versus social, olfactory stimuli, but did not demonstrate cognitive rigidity following familiarization to an appetitive stimulus. Analysis of available high-density genotype data indicated specific regions of divergence between C58/J and two highly-sociable strains with common genetic lineage. Strain genome comparisons identified autism candidate genes, including Cntnap2 and Slc6a4, located within regions divergent in C58/J. However, Grin1, Nlgn1, Sapap3, and Slitrk5, genes linked to repetitive over-grooming, were not in regions of divergence. These studies suggest that specific repetitive phenotypes can be used to distinguish ASD mouse models, with implications for divergent underlying mechanisms for different repetitive behavior profiles.
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Hondo T, Warizaya M, Niimi T, Namatame I, Yamaguchi T, Nakanishi K, Hamajima T, Harada K, Sakashita H, Matsumoto Y, Orita M, Takeuchi M. 4-Hydroxypyridazin-3(2H)-one derivatives as novel D-amino acid oxidase inhibitors. J Med Chem 2013; 56:3582-92. [PMID: 23566269 DOI: 10.1021/jm400095b] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
D-Amino acid oxidase (DAAO) catalyzes the oxidation of d-amino acids including d-serine, a coagonist of the N-methyl-d-aspartate receptor. We identified a series of 4-hydroxypyridazin-3(2H)-one derivatives as novel DAAO inhibitors with high potency and substantial cell permeability using fragment-based drug design. Comparisons of complex structures deposited in the Protein Data Bank as well as those determined with in-house fragment hits revealed that a hydrophobic subpocket was formed perpendicular to the flavin ring by flipping Tyr224 in a ligand-dependent manner. We investigated the ability of the initial fragment hit, 3-hydroxy-pyridine-2(1H)-one, to fill this subpocket with the aid of complex structure information. 3-Hydroxy-5-(2-phenylethyl)pyridine-2(1H)-one exhibited the predicted binding mode and demonstrated high inhibitory activity for human DAAO in enzyme- and cell-based assays. We further designed and synthesized 4-hydroxypyridazin-3(2H)-one derivatives, which are equivalent to the 3-hydroxy-pyridine-2(1H)-one series but lack cell toxicity. 6-[2-(3,5-Difluorophenyl)ethyl]-4-hydroxypyridazin-3(2H)-one was found to be effective against MK-801-induced cognitive deficit in the Y-maze.
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Affiliation(s)
- Takeshi Hondo
- Drug Discovery Research, Astellas Pharma Inc., 21 Miyukigaoka, Tsukuba, Ibaraki 305-8585, Japan.
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Mihali A, Subramani S, Kaunitz G, Rayport S, Gaisler-Salomon I. Modeling resilience to schizophrenia in genetically modified mice: a novel approach to drug discovery. Expert Rev Neurother 2012; 12:785-99. [PMID: 22853787 DOI: 10.1586/ern.12.60] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Complex psychiatric disorders, such as schizophrenia, arise from a combination of genetic, developmental, environmental and social factors. These vulnerabilities can be mitigated by adaptive factors in each of these domains engendering resilience. Modeling resilience in mice using transgenic approaches offers a direct path to intervention, as resilience mutations point directly to therapeutic targets. As prototypes for this approach, we discuss the three mouse models of schizophrenia resilience, all based on modulating glutamatergic synaptic transmission. This motivates the broader development of schizophrenia resilience mouse models independent of specific pathophysiological hypotheses as a strategy for drug discovery. Three guiding validation criteria are presented. A resilience-oriented approach should identify pharmacologically tractable targets and in turn offer new insights into pathophysiological mechanisms.
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Affiliation(s)
- Andra Mihali
- Department of Psychiatry, Columbia University, New York State Psychiatric Institute, 1051 Riverside Drive, Unit 62, New York, NY 10032, USA
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Yamanaka M, Miyoshi Y, Ohide H, Hamase K, Konno R. d-Amino acids in the brain and mutant rodents lacking d-amino-acid oxidase activity. Amino Acids 2012; 43:1811-21. [DOI: 10.1007/s00726-012-1384-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2012] [Accepted: 07/30/2012] [Indexed: 12/27/2022]
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Strick CA, Li C, Scott L, Harvey B, Hajós M, Steyn SJ, Piotrowski MA, James LC, Downs JT, Rago B, Becker SL, El-Kattan A, Xu Y, Ganong AH, Tingley FD, Ramirez AD, Seymour PA, Guanowsky V, Majchrzak MJ, Fox CB, Schmidt CJ, Duplantier AJ. Modulation of NMDA receptor function by inhibition of D-amino acid oxidase in rodent brain. Neuropharmacology 2011; 61:1001-15. [PMID: 21763704 DOI: 10.1016/j.neuropharm.2011.06.029] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Revised: 06/28/2011] [Accepted: 06/29/2011] [Indexed: 01/16/2023]
Abstract
Observations that N-Methyl-D-Aspartate (NMDA) antagonists produce symptoms in humans that are similar to those seen in schizophrenia have led to the current hypothesis that schizophrenia might result from NMDA receptor hypofunction. Inhibition of D-amino acid oxidase (DAAO), the enzyme responsible for degradation of D-serine, should lead to increased levels of this co-agonist at the NMDA receptor, and thereby provide a therapeutic approach to schizophrenia. We have profiled some of the preclinical biochemical, electrophysiological, and behavioral consequences of administering potent and selective inhibitors of DAAO to rodents to begin to test this hypothesis. Inhibition of DAAO activity resulted in a significant dose and time dependent increase in D-serine only in the cerebellum, although a time delay was observed between peak plasma or brain drug concentration and cerebellum D-serine response. Pharmacokinetic/pharmacodynamic (PK/PD) modeling employing a mechanism-based indirect response model was used to characterize the correlation between free brain drug concentration and D-serine accumulation. DAAO inhibitors had little or no activity in rodent models considered predictive for antipsychotic activity. The inhibitors did, however, affect cortical activity in the Mescaline-Induced Scratching model, produced a modest but significant increase in NMDA receptor-mediated synaptic currents in primary neuronal cultures from rat hippocampus, and resulted in a significant increase in evoked hippocampal theta rhythm, an in vivo electrophysiological model of hippocampal activity. These findings demonstrate that although DAAO inhibition did not cause a measurable increase in D-serine in forebrain, it did affect hippocampal and cortical activity, possibly through augmentation of NMDA receptor-mediated currents.
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MESH Headings
- Animals
- Brain/drug effects
- Brain/metabolism
- Central Nervous System Stimulants/metabolism
- Central Nervous System Stimulants/pharmacology
- Cyclic GMP/analysis
- Cyclic GMP/biosynthesis
- D-Amino-Acid Oxidase/antagonists & inhibitors
- D-Amino-Acid Oxidase/metabolism
- D-Amino-Acid Oxidase/physiology
- Drug Evaluation, Preclinical
- Electroencephalography
- Habituation, Psychophysiologic/drug effects
- Habituation, Psychophysiologic/physiology
- Harmaline/metabolism
- Hippocampus/drug effects
- Hippocampus/metabolism
- Male
- Maze Learning/drug effects
- Maze Learning/physiology
- Memory, Short-Term/drug effects
- Memory, Short-Term/physiology
- Mescaline/pharmacology
- Mice
- Miniature Postsynaptic Potentials/drug effects
- Miniature Postsynaptic Potentials/physiology
- Models, Biological
- Models, Chemical
- Molecular Targeted Therapy
- Motor Activity/drug effects
- Motor Activity/physiology
- Pruritus/chemically induced
- Pruritus/prevention & control
- Psychomotor Agitation/drug therapy
- Rats
- Rats, Long-Evans
- Rats, Sprague-Dawley
- Receptors, N-Methyl-D-Aspartate/drug effects
- Receptors, N-Methyl-D-Aspartate/metabolism
- Sensory Gating/drug effects
- Sensory Gating/physiology
- Serine/blood
- Serotonin Receptor Agonists/pharmacology
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Labrie V, Wong AHC, Roder JC. Contributions of the D-serine pathway to schizophrenia. Neuropharmacology 2011; 62:1484-503. [PMID: 21295046 DOI: 10.1016/j.neuropharm.2011.01.030] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2010] [Revised: 01/16/2011] [Accepted: 01/19/2011] [Indexed: 01/30/2023]
Abstract
The glutamate neurotransmitter system is one of the major candidate pathways for the pathophysiology of schizophrenia, and increased understanding of the pharmacology, molecular biology and biochemistry of this system may lead to novel treatments. Glutamatergic hypofunction, particularly at the NMDA receptor, has been hypothesized to underlie many of the symptoms of schizophrenia, including psychosis, negative symptoms and cognitive impairment. This review will focus on D-serine, a co-agonist at the NMDA receptor that in combination with glutamate, is required for full activation of this ion channel receptor. Evidence implicating D-serine, NMDA receptors and related molecules, such as D-amino acid oxidase (DAO), G72 and serine racemase (SRR), in the etiology or pathophysiology of schizophrenia is discussed, including knowledge gained from mouse models with altered D-serine pathway genes and from preliminary clinical trials with D-serine itself or compounds modulating the D-serine pathway. Abnormalities in D-serine availability may underlie glutamatergic dysfunction in schizophrenia, and the development of new treatments acting through the D-serine pathway may significantly improve outcomes for many schizophrenia patients.
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Affiliation(s)
- Viviane Labrie
- Krembil Family Epigenetics Laboratory, Centre for Addiction and Mental Health, 250 College St, Toronto, ON M5T 1R8, Canada.
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11
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Burnet PW, Anderson PN, Chen L, Nikiforova N, Harrison PJ, Wood MJ. d-Amino acid oxidase knockdown in the mouse cerebellum reduces NR2A mRNA. Mol Cell Neurosci 2011; 46:167-75. [DOI: 10.1016/j.mcn.2010.08.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Revised: 08/27/2010] [Accepted: 08/30/2010] [Indexed: 12/24/2022] Open
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Abstract
D-amino acid oxidase (DAO) is a flavoenzyme that metabolizes certain D-amino acids, notably the endogenous N-methyl D-aspartate receptor (NMDAR) co-agonist, D-serine. As such, it has the potential to modulate the function of NMDAR and to contribute to the widely hypothesized involvement of NMDAR signalling in schizophrenia. Three lines of evidence now provide support for this possibility: DAO shows genetic associations with the disorder in several, although not all, studies; the expression and activity of DAO are increased in schizophrenia; and DAO inactivation in rodents produces behavioural and biochemical effects, suggestive of potential therapeutic benefits. However, several key issues remain unclear. These include the regional, cellular and subcellular localization of DAO, the physiological importance of DAO and its substrates other than D-serine, as well as the causes and consequences of elevated DAO in schizophrenia. Herein, we critically review the neurobiology of DAO, its involvement in schizophrenia, and the therapeutic value of DAO inhibition. This review also highlights issues that have a broader relevance beyond DAO itself: how should we weigh up convergent and cumulatively impressive, but individually inconclusive, pieces of evidence regarding the role that a given gene may have in the aetiology, pathophysiology and pharmacotherapy of schizophrenia?
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Kirby BP, Waddington JL, O'Tuathaigh CMP. Advancing a functional genomics for schizophrenia: psychopathological and cognitive phenotypes in mutants with gene disruption. Brain Res Bull 2009; 83:162-76. [PMID: 19800398 DOI: 10.1016/j.brainresbull.2009.09.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2009] [Revised: 08/18/2009] [Accepted: 09/21/2009] [Indexed: 12/19/2022]
Abstract
Schizophrenia is a complex, heritable psychotic disorder in which numerous genes and environmental adversities appear to interact in determining disease phenotype. In addition to genes regulating putative pathophysiological mechanisms, a new generation of molecular studies has indicated numerous candidate genes to be associated with risk for schizophrenia. The present review focuses on studies in mice mutant for genes associated with putative pathophysiological mechanisms and candidate risk genes for the disorder. It seeks to evaluate the extent to which each mutation of a schizophrenia-related gene accurately models multiple aspects of the schizophrenia phenotype or more circumscribed, distinct endophenotypes in terms of psychopathology and pathobiology; in doing so, it places particular emphasis on positive symptoms, negative symptoms and cognitive dysfunction. To further this goal, it juxtaposes continually evolving mutant genomics with emergent clinical genomic studies. Opportunities and challenges associated with the use of such mutants, including diagnostic specificity and the translational barrier associated with modelling schizophrenia, are discussed. The potential value of genetic models for exploring gene-gene and gene-environment interactions relating to schizophrenia is highlighted. Elucidation of the contribution of genetic variation to specific symptom clusters and underlying aspects of pathobiology will have important implications for identifying treatments that target distinct domains of psychopathology and dysfunction on an individual patient basis.
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Affiliation(s)
- Brian P Kirby
- School of Pharmacy, Royal College of Surgeons in Ireland, Dublin 2, Ireland
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Desbonnet L, Waddington JL, Tuathaigh CMPO. Mice mutant for genes associated with schizophrenia: common phenotype or distinct endophenotypes? Behav Brain Res 2009; 204:258-73. [PMID: 19728400 DOI: 10.1016/j.bbr.2009.04.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Schizophrenia is a complex neuropsychiatric disorder whose etiology involves a mixture of genetic and environmental factors. By virtue of this complexity, schizophrenia is a field of research in which a number of key technologies converge: in particular, identification of putative susceptibility genes through association studies in clinical populations leads to investigation of the behavioural roles of these genes by targeted manipulation in mice and their phenotypic characterisation ('gene-driven' approach); in a complementary manner, identification of putative pathophysiological processes and therapeutic pathways leads to investigation of behavioural phenotype in mice mutant for genes regulating such processes and pathways ('phenotype-driven' approach). As several susceptibility genes for schizophrenia and numerous genes implicated in the pathophysiology of schizophrenia have now been genetically manipulated in mice, it is timely to consider the roles of these genes in abnormal brain development and the ontogeny of putative schizophrenia-like phenotypes. The aim of this review is to outline existing knowledge from mutant studies concerning the contribution of these genes to the development of a common schizophrenia phenotype vis-à-vis discrete schizophrenia endophenotypes. Emphasis is also placed on the importance of studying gene x environment and gene x gene interactions, as well as addressing methodological issues related to genetic modelling and phenotyping strategies.
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Affiliation(s)
- Lieve Desbonnet
- Molecular & Cellular Therapeutics, Royal College of Surgeons in Ireland, St. Stephen's Green, Dublin 2, Ireland
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Labrie V, Roder JC. The involvement of the NMDA receptor D-serine/glycine site in the pathophysiology and treatment of schizophrenia. Neurosci Biobehav Rev 2009; 34:351-72. [PMID: 19695284 DOI: 10.1016/j.neubiorev.2009.08.002] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Revised: 08/10/2009] [Accepted: 08/11/2009] [Indexed: 01/11/2023]
Abstract
Hypofunction of the N-methyl-D-aspartate receptor (NMDAR) has been implicated in the pathophysiology of schizophrenia. The NMDAR contains a D-serine/glycine site on the NR1 subunit that may be a promising therapeutic target for psychiatric illness. This review outlines the complex regulation of endogenous NMDAR D-serine/glycine site agonists and explores their contribution to schizophrenia pathogenesis and their potential clinical utility. Genetic studies have associated genes influencing NMDAR D-serine/glycine site activation with an increased susceptibility to schizophrenia. Postmortem studies have identified abnormalities in several transcripts affecting D-serine/glycine site activity, consistent with in vivo reports of alterations in levels of endogenous D-serine/glycine site agonists and antagonists. Genetically modified mice with aberrant NMDAR D-serine/glycine site function model certain features of the negative and cognitive symptoms of schizophrenia, and similar behavioral abnormalities have been observed in other candidate genes models. Compounds that directly activate the NMDAR D-serine/glycine site or inhibit glycine transport have demonstrated beneficial effects in preclinical models and clinical trials. Future pharmacological approaches for schizophrenia treatment may involve targeting enzymes that affect D-serine synthesis and metabolism.
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Affiliation(s)
- Viviane Labrie
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada.
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Millan MJ, Brocco M. Cognitive Impairment in Schizophrenia: a Review of Developmental and Genetic Models, and Pro-cognitive Profile of the Optimised D3 > D2 Antagonist, S33138. Therapie 2008; 63:187-229. [DOI: 10.2515/therapie:2008041] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/02/2008] [Indexed: 01/23/2023]
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