1
|
Treatment-Resistant Schizophrenia, Clozapine Resistance, Genetic Associations, and Implications for Precision Psychiatry: A Scoping Review. Genes (Basel) 2023; 14:genes14030689. [PMID: 36980961 PMCID: PMC10048540 DOI: 10.3390/genes14030689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 03/03/2023] [Accepted: 03/08/2023] [Indexed: 03/14/2023] Open
Abstract
Treatment-resistant schizophrenia (TRS) is often associated with severe burden of disease, poor quality of life and functional impairment. Clozapine is the gold standard for the treatment of TRS, although it is also known to cause significant side effects in some patients. In view of the burgeoning interest in the role of genetic factors in precision psychiatry, we conducted a scoping review to narratively summarize the current genetic factors associated with TRS, clozapine resistance and side effects to clozapine treatment. We searched PubMed from inception to December 2022 and included 104 relevant studies in this review. Extant evidence comprised associations between TRS and clozapine resistance with genetic factors related to mainly dopaminergic and serotoninergic neurotransmitter systems, specifically, TRS and rs4680, rs4818 within COMT, and rs1799978 within DRD2; clozapine resistance and DRD3 polymorphisms, CYP1A2 polymorphisms; weight gain with LEP and SNAP-25 genes; and agranulocytosis risk with HLA-related polymorphisms. Future studies, including replication in larger multi-site samples, are still needed to elucidate putative risk genes and the interactions between different genes and their correlations with relevant clinical factors such as psychopathology, psychosocial functioning, cognition and progressive changes with treatment over time in TRS and clozapine resistance.
Collapse
|
2
|
Jiao S, Cao T, Cai H. Peripheral biomarkers of treatment-resistant schizophrenia: Genetic, inflammation and stress perspectives. Front Pharmacol 2022; 13:1005702. [PMID: 36313375 PMCID: PMC9597880 DOI: 10.3389/fphar.2022.1005702] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 09/26/2022] [Indexed: 11/16/2022] Open
Abstract
Treatment-resistant schizophrenia (TRS) often results in severe disability and functional impairment. Currently, the diagnosis of TRS is largely exclusionary and emphasizes the improvement of symptoms that may not be detected early and treated according to TRS guideline. As the gold standard, clozapine is the most prescribed selection for TRS. Therefore, how to predict TRS in advance is critical for forming subsequent treatment strategy especially clozapine is used during the early stage of TRS. Although mounting studies have identified certain clinical factors and neuroimaging characteristics associated with treatment response in schizophrenia, the predictors for TRS remain to be explored. Biomarkers, particularly for peripheral biomarkers, show great potential in predicting TRS in view of their predictive validity, noninvasiveness, ease of testing and low cost that would enable their widespread use. Recent evidence supports that the pathogenesis of TRS may be involved in abnormal neurotransmitter systems, inflammation and stress. Due to the heterogeneity of TRS and the lack of consensus in diagnostic criteria, it is difficult to compare extensive results among different studies. Based on the reported neurobiological mechanisms that may be associated with TRS, this paper narratively reviews the updates of peripheral biomarkers of TRS, from genetic and other related perspectives. Although current evidence regarding biomarkers in TRS remains fragmentary, when taken together, it can help to better understand the neurobiological interface of clinical phenotypes and psychiatric symptoms, which will enable individualized prediction and therapy for TRS in the long run.
Collapse
Affiliation(s)
- Shimeng Jiao
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China
- Institute of Clinical Pharmacy, Central South University, Changsha, China
- International Research Center for Precision Medicine, Transformative Technology and Software Services, Changsha, Hunan, China
| | - Ting Cao
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China
- Institute of Clinical Pharmacy, Central South University, Changsha, China
- International Research Center for Precision Medicine, Transformative Technology and Software Services, Changsha, Hunan, China
| | - Hualin Cai
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China
- Institute of Clinical Pharmacy, Central South University, Changsha, China
- International Research Center for Precision Medicine, Transformative Technology and Software Services, Changsha, Hunan, China
- *Correspondence: Hualin Cai,
| |
Collapse
|
3
|
Dogra S, Conn PJ. Metabotropic glutamate receptors as emerging targets for the treatment of schizophrenia. Mol Pharmacol 2022; 101:275-285. [PMID: 35246479 PMCID: PMC9092465 DOI: 10.1124/molpharm.121.000460] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 02/22/2022] [Indexed: 11/22/2022] Open
Abstract
Accumulating evidence of glutamatergic abnormalities in the brains of schizophrenia patients has led to efforts to target various components of glutamatergic signaling as potential new approaches for schizophrenia. Exciting research suggests that metabotropic glutamate (mGlu) receptors could provide a fundamentally new approach for better symptomatic relief in schizophrenia patients. In preclinical studies, the mGlu5 receptor positive allosteric modulators (PAMs) have efficacy in animal models relevant for all symptom domains in schizophrenia. Interestingly, biased pure mGlu5 receptor PAMs that do not potentiate coupling of mGlu5 receptors to NMDA receptors lack neurotoxic effects associated with mGlu5 PAMs that enhance coupling to N-methyl-D-aspartate (NMDA) receptors or have allosteric agonist activity (ago-PAMs). This provides a better therapeutic profile for treating schizophrenia-like symptoms. Additionally, the mGlu1 receptor PAMs modulate dopamine release in the striatum, which may contribute to their antipsychotic-like effects. Besides group I mGlu (mGlu1 and mGlu5) receptors, agonists of mGlu2/3 receptor also induce robust antipsychotic-like and pro-cognitive effects in rodents and may be effective in treating symptoms of schizophrenia in a selective group of patients. Additionally, mGlu2/4 receptor heterodimers modulate glutamatergic neurotransmission in the prefrontal cortex at selective synapses activated in schizophrenia and, therefore, hold potential as novel antipsychotics. Excitingly, the mGlu3 receptor activation can enhance cognition in rodents suggesting that mGlu3 receptor agonist/PAM could provide a novel approach for the treatment of cognitive deficits in schizophrenia. Collectively, the development of mGlu receptor-specific ligands may provide an alternative approach to meet the clinical need for safer and efficacious therapeutics for schizophrenia. Significance Statement The currently available antipsychotic medications do not show significant efficacy for treating negative symptoms and cognitive deficits in schizophrenia. Emerging preclinical and clinical literature suggests that pharmacological targeting of metabotropic glutamate receptors could potentially provide an alternative approach for designing safer and efficacious therapeutics for treating schizophrenia.
Collapse
|
4
|
Vita A, Minelli A, Barlati S, Deste G, Giacopuzzi E, Valsecchi P, Turrina C, Gennarelli M. Treatment-Resistant Schizophrenia: Genetic and Neuroimaging Correlates. Front Pharmacol 2019; 10:402. [PMID: 31040787 PMCID: PMC6476957 DOI: 10.3389/fphar.2019.00402] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Accepted: 04/01/2019] [Indexed: 12/11/2022] Open
Abstract
Schizophrenia is a severe neuropsychiatric disorder that affects approximately 0.5–1% of the population. Response to antipsychotic therapy is highly variable, and it is not currently possible to predict those patients who will or will not respond to antipsychotic medication. Furthermore, a high percentage of patients, approximately 30%, are classified as treatment-resistant (treatment-resistant schizophrenia; TRS). TRS is defined as a non-response to at least two trials of antipsychotic medication of adequate dose and duration. These patients are usually treated with clozapine, the only evidence-based pharmacotherapy for TRS. However, clozapine is associated with severe adverse events. For these reasons, there is an increasing interest to identify better targets for drug development of new compounds and to establish better biomarkers for existing medications. The ability of antipsychotics to improve psychotic symptoms is dependent on their antagonist and reverse agonist activities at different neuroreceptors, and some genetic association studies of TRS have focused on different pharmacodynamic factors. Some genetic studies have shown an association between antipsychotic response or TRS and neurodevelopment candidate genes, antipsychotic mechanisms of action (such as dopaminergic, serotonergic, GABAergic, and glutamatergic) or pharmacokinetic factors (i.e., differences in the cytochrome families). Moreover, there is a growing body of literature on the structural and functional neuroimaging research into TRS. Neuroimaging studies can help to uncover the underlying neurobiological reasons for such resistance and identify resistant patients earlier. Studies examining the neuropharmacological mechanisms of antipsychotics, including clozapine, can help to improve our knowledge of their action on the central nervous system, with further implications for the discovery of biomarkers and the development of new treatments. The identification of the underlying mechanisms of TRS is a major challenge for developing personalized medicine in the psychiatric field for schizophrenia treatment. The main goal of precision medicine is to use genetic and brain-imaging information to improve the safety, effectiveness, and health outcomes of patients via more efficiently targeted risk stratification, prevention, and tailored medication and treatment management approaches. The aim of this review is to summarize the state of art of pharmacogenetic, pharmacogenomic and neuroimaging studies in TRS.
Collapse
Affiliation(s)
- Antonio Vita
- Department of Mental Health and Addiction Services, ASST Spedali Civili, Brescia, Italy.,Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Alessandra Minelli
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Stefano Barlati
- Department of Mental Health and Addiction Services, ASST Spedali Civili, Brescia, Italy.,Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Giacomo Deste
- Department of Mental Health and Addiction Services, ASST Spedali Civili, Brescia, Italy
| | - Edoardo Giacopuzzi
- Genetic Unit, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Paolo Valsecchi
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Cesare Turrina
- Department of Mental Health and Addiction Services, ASST Spedali Civili, Brescia, Italy.,Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Massimo Gennarelli
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.,Genetic Unit, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| |
Collapse
|
5
|
Nicoletti F, Orlando R, Di Menna L, Cannella M, Notartomaso S, Mascio G, Iacovelli L, Matrisciano F, Fazio F, Caraci F, Copani A, Battaglia G, Bruno V. Targeting mGlu Receptors for Optimization of Antipsychotic Activity and Disease-Modifying Effect in Schizophrenia. Front Psychiatry 2019; 10:49. [PMID: 30890967 PMCID: PMC6413697 DOI: 10.3389/fpsyt.2019.00049] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 01/23/2019] [Indexed: 01/03/2023] Open
Abstract
Metabotropic glutamate (mGlu) receptors are considered as candidate drug targets for the treatment of schizophrenia. These receptors form a family of eight subtypes (mGlu1 to -8), of which mGlu1 and -5 are coupled to Gq/11, and all other subtypes are coupled to Gi/o. Here, we discuss the possibility that selective ligands of individual mGlu receptor subtypes may be effective in controlling the core symptoms of schizophrenia, and, in some cases, may impact mechanisms underlying the progression of the disorder. Recent evidence indicates that activation of mGlu1 receptors inhibits dopamine release in the meso-striatal system. Hence, selective positive allosteric modulators (PAMs) of mGlu1 receptors hold promise for the treatment of positive symptoms of schizophrenia. mGlu5 receptors are widely expressed in the CNS and regulate the activity of cells that are involved in the pathophysiology of schizophrenia, such as cortical GABAergic interneurons and microglial cells. mGlu5 receptor PAMs are under development for the treatment of schizophrenia and cater the potential to act as disease modifiers by restraining neuroinflammation. mGlu2 receptors have attracted considerable interest because they negatively modulate 5-HT2A serotonin receptor signaling in the cerebral cortex. Both mGlu2 receptor PAMs and orthosteric mGlu2/3 receptor agonists display antipsychotic-like activity in animal models, and the latter drugs are inactive in mice lacking mGlu2 receptors. So far, mGlu3 receptors have been left apart as drug targets for schizophrenia. However, activation of mGlu3 receptors boosts mGlu5 receptor signaling, supports neuronal survival, and drives microglial cells toward an antiinflammatory phenotype. This strongly encourages research of mGlu3 receptors in schizophrenia. Finally, preclical studies suggest that mGlu4 receptors might be targeted by novel antipsychotic drugs, whereas studies of mGlu7 and mGlu8 receptors in animal models of psychosis are still at their infancy.
Collapse
Affiliation(s)
- Ferdinando Nicoletti
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.,IRCCS Neuromed, Pozzilli, Italy
| | - Rosamaria Orlando
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | | | | | | | | | - Luisa Iacovelli
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Francesco Matrisciano
- Department of Psychiatry, The Psychiatric Institute, College of Medicine, University of Illinois, Chicago, IL, United States
| | | | - Filippo Caraci
- Department of Drug Sciences, University of Catania, Catania, Italy.,Oasi Research Institute (IRCCS), Troina, Italy
| | - Agata Copani
- Department of Drug Sciences, University of Catania, Catania, Italy.,Institute of Biostructure and Bioimaging, National Research Council, Catania, Italy
| | | | - Valeria Bruno
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.,IRCCS Neuromed, Pozzilli, Italy
| |
Collapse
|
6
|
Response to initial antipsychotic treatment in first episode psychosis is related to anterior cingulate glutamate levels: a multicentre 1H-MRS study (OPTiMiSE). Mol Psychiatry 2018; 23:2145-2155. [PMID: 29880882 DOI: 10.1038/s41380-018-0082-9] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 03/15/2018] [Accepted: 04/04/2018] [Indexed: 12/19/2022]
Abstract
Conventional antipsychotic medication is ineffective in around a third of patients with schizophrenia, and the nature of the therapeutic response is unpredictable. We investigated whether response to antipsychotics is related to brain glutamate levels prior to treatment. Proton magnetic resonance spectroscopy was used to measure glutamate levels (Glu/Cr) in the anterior cingulate cortex (ACC) and in the thalamus in antipsychotic-naive or minimally medicated patients with first episode psychosis (FEP, n = 71) and healthy volunteers (n = 60), at three sites. Following scanning, patients were treated with amisulpride for 4 weeks (n = 65), then 1H-MRS was repeated (n = 46). Remission status was defined in terms of Positive and Negative Syndrome Scale for Schizophrenia (PANSS) scores. Higher levels of Glu/Cr in the ACC were associated with more severe symptoms at presentation and a lower likelihood of being in remission at 4 weeks (P < 0.05). There were longitudinal reductions in Glu/Cr in both the ACC and thalamus over the treatment period (P < 0.05), but these changes were not associated with the therapeutic response. There were no differences in baseline Glu/Cr between patients and controls. These results extend previous evidence linking higher levels of ACC glutamate with a poor antipsychotic response by showing that the association is evident before the initiation of treatment.
Collapse
|
7
|
Jin LE, Wang M, Yang ST, Yang Y, Galvin VC, Lightbourne TC, Ottenheimer D, Zhong Q, Stein J, Raja A, Paspalas CD, Arnsten AFT. mGluR2/3 mechanisms in primate dorsolateral prefrontal cortex: evidence for both presynaptic and postsynaptic actions. Mol Psychiatry 2017; 22:1615-1625. [PMID: 27502475 PMCID: PMC5298940 DOI: 10.1038/mp.2016.129] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 05/04/2016] [Accepted: 06/15/2016] [Indexed: 01/12/2023]
Abstract
Cognitive deficits in psychiatric and age-related disorders generally involve dysfunction of the dorsolateral prefrontal cortex (dlPFC), but there are few treatments for these debilitating symptoms. Group II metabotropic glutamate receptors (mGluR2/3), which couple to Gi/Go, have been a focus of therapeutics based on rodent research, where mGluR2/3 have been shown to reduce axonal glutamate release and increase glial glutamate uptake. However, this strategy has had mixed results in patients, and understanding mGluR2/3 mechanisms in primates will help guide therapeutic interventions. The current study examined mGluR2/3 localization and actions in the primate dlPFC layer III circuits underlying working memory, where the persistent firing of 'Delay cells' is mediated by N-methyl-d-aspartate receptors and weakened by cAMP-PKA-potassium channel signaling in dendritic spines. Immunoelectron microscopy identified postsynaptic mGluR2/3 in the spines, in addition to the traditional presynaptic and astrocytic locations. In vivo iontophoretic application of the mGluR2/3 agonists (2R, 4R)-APDC or LY379268 onto dlPFC Delay cells produced an inverted-U effect on working memory representation, with enhanced neuronal firing following low doses of mGluR2/3 agonists. The enhancing effects were reversed by an mGluR2/3 antagonist or by activating cAMP signaling, consistent with mGluR2/3 inhibiting postsynaptic cAMP signaling in spines. Systemic administration of these agonists to monkeys performing a working memory task also produced an inverted-U dose-response, where low doses improved performance but higher doses, similar to clinical trials, had mixed effects. Our data suggest that low doses of mGluR2/3 stimulation may have therapeutic effects through unexpected postsynaptic actions in dlPFC, strengthening synaptic connections and improving cognitive function.
Collapse
Affiliation(s)
- L E Jin
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - M Wang
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - S-T Yang
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Y Yang
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - V C Galvin
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - T C Lightbourne
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - D Ottenheimer
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Q Zhong
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - J Stein
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - A Raja
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - C D Paspalas
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA,Department of Neuroscience, Yale School of Medicine, Yale University, 333 Cedar Street, New Haven, CT 06520, USA. E-mail: or
| | - A F T Arnsten
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA,Department of Neuroscience, Yale School of Medicine, Yale University, 333 Cedar Street, New Haven, CT 06520, USA. E-mail: or
| |
Collapse
|
8
|
Saini SM, Mancuso SG, Mostaid MS, Liu C, Pantelis C, Everall IP, Bousman CA. Meta-analysis supports GWAS-implicated link between GRM3 and schizophrenia risk. Transl Psychiatry 2017; 7:e1196. [PMID: 28786982 PMCID: PMC5611739 DOI: 10.1038/tp.2017.172] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Accepted: 06/20/2017] [Indexed: 12/29/2022] Open
Abstract
Genome-wide association study (GWAS) evidence has identified the metabotropic glutamate receptor 3 (GRM3) gene as a potential harbor for schizophrenia risk variants. However, previous meta-analyses have refuted the association between GRM3 single-nucleotide polymorphisms (SNPs) and schizophrenia risk. To reconcile these conflicting findings, we conducted the largest and most comprehensive meta-analysis of 14 SNPs in GRM3 from a total of 11 318 schizophrenia cases, 13 820 controls and 486 parent-proband trios. We found significant associations for three SNPs (rs2237562: odds ratio (OR)=1.06, 95% confidence interval (CI)=1.02-1.11, P=0.017; rs13242038: OR=0.90, 95% CI=0.85-0.96, P=0.016 and rs917071: OR=0.94, 95% CI=0.91-0.97, P=0.003). Two of these SNPs (rs2237562, rs917071) were in strong-to-moderate linkage disequilibrium with the top GRM3 GWAS significant SNP (rs12704290) reported by the Schizophrenia Working Group of the Psychiatric Genomics Consortium. We also found evidence for population stratification related to rs2237562 in that the 'risk' allele was dependent on the population under study. Our findings support the GWAS-implicated link between GRM3 genetic variation and schizophrenia risk as well as the notion that alleles conferring this risk may be population specific.
Collapse
Affiliation(s)
- S M Saini
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Parkville, VIC, Australia
- Department of Psychiatry, UKM Medical Center, Jalan Yaacob Latif, Cheras, Kuala Lumpur, Malaysia
| | - S G Mancuso
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Parkville, VIC, Australia
| | - Md S Mostaid
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Parkville, VIC, Australia
| | - C Liu
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Parkville, VIC, Australia
| | - C Pantelis
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Parkville, VIC, Australia
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
- Centre for Neural Engineering, The University of Melbourne, Carlton, VIC, Australia
- North Western Mental Health, Melbourne Health, Parkville, VIC, Australia
| | - I P Everall
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Parkville, VIC, Australia
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
- Centre for Neural Engineering, The University of Melbourne, Carlton, VIC, Australia
- North Western Mental Health, Melbourne Health, Parkville, VIC, Australia
| | - C A Bousman
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Parkville, VIC, Australia
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
- Department of General Practice, The University of Melbourne, Parkville, VIC, Australia
| |
Collapse
|
9
|
Xavier RM, Vorderstrasse A. Genetic Basis of Positive and Negative Symptom Domains in Schizophrenia. Biol Res Nurs 2017; 19:559-575. [PMID: 28691507 DOI: 10.1177/1099800417715907] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Schizophrenia is a highly heritable disorder, the genetic etiology of which has been well established. Yet despite significant advances in genetics research, the pathophysiological mechanisms of this disorder largely remain unknown. This gap has been attributed to the complexity of the polygenic disorder, which has a heterogeneous clinical profile. Examining the genetic basis of schizophrenia subphenotypes, such as those based on particular symptoms, is thus a useful strategy for decoding the underlying mechanisms. This review of literature examines the recent advances (from 2011) in genetic exploration of positive and negative symptoms in schizophrenia. We searched electronic databases PubMed, Web of Science, and Cumulative Index to Nursing and Allied Health Literature using key words schizophrenia, symptoms, positive symptoms, negative symptoms, cognition, genetics, genes, genetic predisposition, and genotype in various combinations. We identified 115 articles, which are included in the review. Evidence from these studies, most of which are genetic association studies, identifies shared and unique gene associations for the symptom domains. Genes associated with neurotransmitter systems and neuronal development/maintenance primarily constitute the shared associations. Needed are studies that examine the genetic basis of specific symptoms within the broader domains in addition to functional mechanisms. Such investigations are critical to developing precision treatment and care for individuals afflicted with schizophrenia.
Collapse
Affiliation(s)
| | - Allison Vorderstrasse
- 2 Duke Center for Applied Genomics and Precision Medicine, Duke University School of Nursing, Durham, NC, USA
| |
Collapse
|
10
|
Panaccione I, Iacovelli L, di Nuzzo L, Nardecchia F, Mauro G, Janiri D, De Blasi A, Sani G, Nicoletti F, Orlando R. Paradoxical sleep deprivation in rats causes a selective reduction in the expression of type-2 metabotropic glutamate receptors in the hippocampus. Pharmacol Res 2017; 117:46-53. [DOI: 10.1016/j.phrs.2016.11.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 11/10/2016] [Accepted: 11/22/2016] [Indexed: 12/12/2022]
|
11
|
Bruno V, Caraci F, Copani A, Matrisciano F, Nicoletti F, Battaglia G. The impact of metabotropic glutamate receptors into active neurodegenerative processes: A "dark side" in the development of new symptomatic treatments for neurologic and psychiatric disorders. Neuropharmacology 2016; 115:180-192. [PMID: 27140693 DOI: 10.1016/j.neuropharm.2016.04.044] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 04/22/2016] [Accepted: 04/28/2016] [Indexed: 12/17/2022]
Abstract
Metabotropic glutamate (mGlu) receptor ligands are under clinical development for the treatment of CNS disorders with high social and economic burden, such as schizophrenia, major depressive disorder (MDD), and Parkinson's disease (PD), and are promising drug candidates for the treatment of Alzheimer's disease (AD). So far, clinical studies have shown symptomatic effects of mGlu receptor ligands, but it is unknown whether these drugs act as disease modifiers or, at the opposite end, they accelerate disease progression by enhancing neurodegeneration. This is a fundamental issue in the treatment of PD and AD, and is also an emerging theme in the treatment of schizophrenia and MDD, in which neurodegeneration is also present and contribute to disease progression. Moving from in vitro data and preclinical studies, we discuss the potential impact of drugs targeting mGlu2, mGlu3, mGlu4 and mGlu5 receptor ligands on active neurodegeneration associated with AD, PD, schizophrenia, and MDD. We wish to highlight that our final comments on the best drug candidates are not influenced by commercial interests or by previous or ongoing collaborations with drug companies. This article is part of the Special Issue entitled 'Metabotropic Glutamate Receptors, 5 years on'.
Collapse
Affiliation(s)
- Valeria Bruno
- Department of Physiology and Pharmacology, University Sapienza, 00185 Rome, Italy; I.R.C.C.S. Neuromed, 86077 Pozzilli, Italy.
| | - Filippo Caraci
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; I.R.C.C.S. Associazione Oasi Maria S.S., Institute for Research on Mental Retardation and Brain Aging, 94018 Troina, Italy
| | - Agata Copani
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; National Research Council, Institute of Biostructure and Bioimaging (IBB-CNR), 95126 Catania, Italy
| | - Francesco Matrisciano
- Department of Psychiatry and Behavioral Sciences, Northwestern Feinberg School of Medicine, Chicago, USA
| | - Ferdinando Nicoletti
- Department of Physiology and Pharmacology, University Sapienza, 00185 Rome, Italy; I.R.C.C.S. Neuromed, 86077 Pozzilli, Italy
| | | |
Collapse
|
12
|
Antipsychotic pharmacogenomics in first episode psychosis: a role for glutamate genes. Transl Psychiatry 2016; 6:e739. [PMID: 26905411 PMCID: PMC4872428 DOI: 10.1038/tp.2016.10] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 12/21/2015] [Indexed: 12/30/2022] Open
Abstract
Genetic factors may underlie beneficial and adverse responses to antipsychotic treatment. These relationships may be easier to identify among patients early in the course of disease who have limited exposure to antipsychotic drugs. We examined 86 first episode patients (schizophrenia, psychotic bipolar disorder and major depressive disorder with psychotic features) who had minimal to no prior antipsychotic exposure in a 6-week pharmacogenomic study of antipsychotic treatment response. Response was measured by change in Brief Psychiatric Rating Scale total score. Risperidone monotherapy was the primary antipsychotic treatment. Pharmacogenomic association studies were completed to (1) examine candidate single-nucleotide polymorphisms (SNPs) in genes known to be involved with glutamate signaling, and (2) conduct an exploratory genome-wide association study of symptom response to identify potential novel associations for future investigation. Two SNPs in GRM7 (rs2069062 and rs2014195) were significantly associated with antipsychotic response in candidate gene analysis, as were two SNPs in the human glutamate receptor delta 2 (GRID2) gene (rs9307122 and rs1875705) in genome-wide association analysis. Further examination of these findings with those from a separate risperidone-treated study sample demonstrated that top SNPs in both studies were overrepresented in glutamate genes and that there were similarities in neurodevelopmental gene categories associated with drug response from both study samples. These associations indicate a role for gene variants related to glutamate signaling and antipsychotic response with more broad association patterns indicating the potential importance of genes involved in neuronal development.
Collapse
|
13
|
Kinoshita A, Takizawa R, Koike S, Satomura Y, Kawasaki S, Kawakubo Y, Marumo K, Tochigi M, Sasaki T, Nishimura Y, Kasai K. Effect of metabotropic glutamate receptor-3 variants on prefrontal brain activity in schizophrenia: An imaging genetics study using multi-channel near-infrared spectroscopy. Prog Neuropsychopharmacol Biol Psychiatry 2015; 62:14-21. [PMID: 25914064 DOI: 10.1016/j.pnpbp.2015.04.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 04/16/2015] [Accepted: 04/16/2015] [Indexed: 12/31/2022]
Abstract
BACKGROUND The glutamatergic system is essential for learning and memory through its crucial role in neural development and synaptic plasticity. Genes associated with the glutamatergic system, including metabotropic glutamate receptor (mGluR or GRM) genes, have been implicated in the pathophysiology of schizophrenia. Few studies, however, have investigated a relationship between polymorphism of glutamate-related genes and cortical function in vivo in patients with schizophrenia. We thus explored an association between genetic variations in GRM3 and brain activation driven by a cognitive task in the prefrontal cortex in patients with schizophrenia. MATERIALS AND METHODS Thirty-one outpatients with schizophrenia and 48 healthy controls participated in this study. We measured four candidate single nucleotide polymorphisms (rs274622, rs2299225, rs1468412, and rs6465084) of GRM3, and activity in the prefrontal and temporal cortices during a category version of a verbal fluency task, using a 52-channel near-infrared spectroscopy instrument. RESULTS AND DISCUSSION The rs274622 C carriers with schizophrenia were associated with significantly smaller prefrontal activation than patients with TT genotype. This between-genotype difference tended to be confined to the patient group. GRM3 polymorphisms are associated with prefrontal activation during cognitive task in schizophrenia.
Collapse
Affiliation(s)
- Akihide Kinoshita
- Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Ryu Takizawa
- Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan; MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London SE5 8AF, UK
| | - Shinsuke Koike
- Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan; Office for Mental Health Support, Division for Counseling and Support, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yoshihiro Satomura
- Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Shingo Kawasaki
- Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan; Application Development Office, Hitachi Medical Corporation, Kashiwa City, Chiba 277-0804, Japan
| | - Yuki Kawakubo
- Department of Child Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Kohei Marumo
- Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Mamoru Tochigi
- Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan; Department of Psychiatry, Teikyo University School of Medicine, Itabashi-ku, Tokyo 173-8605, Japan
| | - Tsukasa Sasaki
- Department of Physical and Health Education, Graduate School of Education, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yukika Nishimura
- Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Kiyoto Kasai
- Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan.
| |
Collapse
|
14
|
Reynolds GP, McGowan OO, Dalton CF. Pharmacogenomics in psychiatry: the relevance of receptor and transporter polymorphisms. Br J Clin Pharmacol 2014; 77:654-72. [PMID: 24354796 DOI: 10.1111/bcp.12312] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2013] [Accepted: 10/18/2013] [Indexed: 12/15/2022] Open
Abstract
The treatment of severe mental illness, and of psychiatric disorders in general, is limited in its efficacy and tolerability. There appear to be substantial interindividual differences in response to psychiatric drug treatments that are generally far greater than the differences between individual drugs; likewise, the occurrence of adverse effects also varies profoundly between individuals. These differences are thought to reflect, at least in part, genetic variability. The action of psychiatric drugs primarily involves effects on synaptic neurotransmission; the genes for neurotransmitter receptors and transporters have provided strong candidates in pharmacogenetic research in psychiatry. This paper reviews some aspects of the pharmacogenetics of neurotransmitter receptors and transporters in the treatment of psychiatric disorders. A focus on serotonin, catecholamines and amino acid transmitter systems reflects the direction of research efforts, while relevant results from some genome-wide association studies are also presented. There are many inconsistencies, particularly between candidate gene and genome-wide association studies. However, some consistency is seen in candidate gene studies supporting established pharmacological mechanisms of antipsychotic and antidepressant response with associations of functional genetic polymorphisms in, respectively, the dopamine D2 receptor and serotonin transporter and receptors. More recently identified effects of genes related to amino acid neurotransmission on the outcome of treatment of schizophrenia, bipolar illness or depression reflect the growing understanding of the roles of glutamate and γ-aminobutyric acid dysfunction in severe mental illness. A complete understanding of psychiatric pharmacogenomics will also need to take into account epigenetic factors, such as DNA methylation, that influence individual responses to drugs.
Collapse
Affiliation(s)
- Gavin P Reynolds
- Biomedical Research Centre, Sheffield Hallam University, Sheffield, UK
| | | | | |
Collapse
|
15
|
Orlando R, Borro M, Motolese M, Molinaro G, Scaccianoce S, Caruso A, di Nuzzo L, Caraci F, Matrisciano F, Pittaluga A, Mairesse J, Simmaco M, Nisticò R, Monn JA, Nicoletti F. Levels of the Rab GDP dissociation inhibitor (GDI) are altered in the prenatal restrain stress mouse model of schizophrenia and are differentially regulated by the mGlu2/3 receptor agonists, LY379268 and LY354740. Neuropharmacology 2014; 86:133-44. [PMID: 25063582 DOI: 10.1016/j.neuropharm.2014.07.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Revised: 07/07/2014] [Accepted: 07/09/2014] [Indexed: 11/24/2022]
Abstract
LY379268 and LY354740, two agonists of mGlu2/3 metabotropic glutamate receptors, display different potencies in mouse models of schizophrenia. This differential effect of the two drugs remains unexplained. We performed a proteomic analysis in cultured cortical neurons challenged with either LY379268 or LY354740. Among the few proteins that were differentially influenced by the two drugs, Rab GDP dissociation inhibitor-β (Rab GDIβ) was down-regulated by LY379268 and showed a trend to an up-regulation in response to LY354740. In cultured hippocampal neurons, LY379268 selectively down-regulated the α isoform of Rab GDI. Rab GDI inhibits the activity of the synaptic vesicle-associated protein, Rab3A, and is reduced in the brain of schizophrenic patients. We examined the expression of Rab GDI in mice exposed to prenatal stress ("PRS mice"), which have been described as a putative model of schizophrenia. Rab GDIα protein levels were increased in the hippocampus of PRS mice at postnatal days (PND)1 and 21, but not at PND60. At PND21, PRS mice also showed a reduced depolarization-evoked [(3)H]d-aspartate release in hippocampal synaptosomes. The increase in Rab GDIα levels in the hippocampus of PRS mice was reversed by a 7-days treatment with LY379268 (1 or 10 mg/kg, i.p.), but not by treatment with equal doses of LY354740. These data strengthen the validity of PRS mice as a model of schizophrenia, and show for the first time a pharmacodynamic difference between LY379268 and LY354740 which might be taken into account in an attempt to explain the differential effect of the two drugs across mouse models.
Collapse
Affiliation(s)
- Rosamaria Orlando
- IRCCS Associazione Oasi Maria S.S., Institute for Research on Mental Retardation and Brain Aging, Troina, Enna, Italy
| | - Marina Borro
- NESMOS Department, Advanced Molecular Diagnostic Unit, Sapienza University, Sant'Andrea Hospital, Rome, Italy
| | | | | | - Sergio Scaccianoce
- Department of Physiology and Pharmacology, University of Rome Sapienza, Rome, Italy
| | - Alessandra Caruso
- Department of Physiology and Pharmacology, University of Rome Sapienza, Rome, Italy
| | - Luigi di Nuzzo
- Department of Physiology and Pharmacology, University of Rome Sapienza, Rome, Italy
| | - Filippo Caraci
- IRCCS Associazione Oasi Maria S.S., Institute for Research on Mental Retardation and Brain Aging, Troina, Enna, Italy; Department of Educational Sciences, University of Catania, Catania, Italy
| | | | - Anna Pittaluga
- Department of Pharmacy, Section of Pharmacology and Toxicology, University of Genoa, Genoa, Italy
| | - Jerome Mairesse
- Neural Plasticity Team, Université Lille 1, International Associated Laboratory (LIA), France
| | - Maurizio Simmaco
- NESMOS Department, Advanced Molecular Diagnostic Unit, Sapienza University, Sant'Andrea Hospital, Rome, Italy
| | - Robert Nisticò
- Department of Physiology and Pharmacology, University of Rome Sapienza, Rome, Italy
| | - James A Monn
- Discovery Chemistry Research and Technologies, Eli Lilly and Company, Indianapolis, IN 46285, USA
| | - Ferdinando Nicoletti
- IRCCS Neuromed, Pozzilli, Italy; Department of Physiology and Pharmacology, University of Rome Sapienza, Rome, Italy.
| |
Collapse
|
16
|
Association of variants in DRD2 and GRM3 with motor and cognitive function in first-episode psychosis. Eur Arch Psychiatry Clin Neurosci 2014; 264:345-55. [PMID: 24682224 PMCID: PMC4290665 DOI: 10.1007/s00406-013-0464-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Accepted: 10/16/2013] [Indexed: 12/16/2022]
Abstract
Similar smooth pursuit eye tracking dysfunctions are present across psychotic disorders. They include pursuit initiation and maintenance deficits that implicate different functional brain systems. This candidate gene study examined psychosis-related genotypes regulating dopamine and glutamate neurotransmission in relation to these pursuit deficits. One hundred and thirty-eight untreated first-episode patients with a psychotic disorder were genotyped for four markers in DRD2 and four markers in GRM3. The magnitude of eye movement abnormality in patients was defined in relation to performance of matched healthy controls (N = 130). Eighty three patients were followed after 6 weeks of antipsychotic treatment. At baseline, patients with a -141C deletion in DRD2 rs1799732 had slower initiation eye velocity and longer pursuit latency than CC insertion carriers. Further, GRM3 rs274622_CC carriers had poorer pursuit maintenance than T-carriers. Antipsychotic treatment resulted in prolonged pursuit latency in DRD2 rs1799732_CC insertion carriers and a decline in pursuit maintenance in GRM3 rs6465084_GG carriers. The present study demonstrates for the first time that neurophysiological measures of motor and neurocognitive deficits in patients with psychotic disorders have different associations with genes regulating dopamine and glutamate systems, respectively. Alterations in striatal D2 receptor activity through the -141C Ins/Del polymorphism could contribute to pursuit initiation deficits in psychotic disorders. Alterations in GRM3 coding for the mGluR3 protein may impair pursuit maintenance by compromising higher perceptual and cognitive processes that depend on optimal glutamate signaling in corticocortical circuits. DRD2 and GRM3 genotypes also selectively modulated the severity of adverse motor and neurocognitive changes resulting from antipsychotic treatment.
Collapse
|
17
|
Mounce J, Luo L, Caprihan A, Liu J, Perrone-Bizzozero N, Calhoun V. Association of GRM3 polymorphism with white matter integrity in schizophrenia. Schizophr Res 2014; 155:8-14. [PMID: 24680030 PMCID: PMC4022143 DOI: 10.1016/j.schres.2014.03.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 03/01/2014] [Accepted: 03/03/2014] [Indexed: 11/30/2022]
Abstract
BACKGROUND While the functional disconnectivity hypothesis of schizophrenia has received considerable attention, fewer studies have investigated the contribution of genotype to structural connectivity between brain regions either in schizophrenia patients or in healthy controls. In this study, we obtained diffusion tensor imaging (DTI) data and genome-wide single nucleotide polymorphism (SNP) data from 74 cases and 87 age- and gender-matched controls. METHODS We used independent component analysis (ICA) to analyze fractional anisotropy (FA) values and correlated FA values with 121 SNPs in genes associated with myelination and/or schizophrenia risk. RESULTS Using ICA, we identified 6 maximally independent components in which the majority of the voxels corresponded to known white matter (WM) tracts. Among these WM-enriched components, two had FA values that were significantly decreased in patients. In addition, we examined the relationship between FA values and genotype and found that a SNP located in the intronic region of the metabotropic glutamate receptor 3 gene, GRM3, shows a significant correlation with FA values in a component containing tracts from the cortico-cerebellar-thalamic-cortical circuit of patients but not controls. CONCLUSIONS Our findings strengthen the evidence for an association between GRM3 genotype and schizophrenia and suggest a role for glutamate neurotransmission in the establishment and maintenance of myelinated fibers.
Collapse
Affiliation(s)
- Joanna Mounce
- Department of Neuroscience, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - Li Luo
- The Mind Research Network (MRN) and Lovelace Biomedical and Environmental Research Institute, Albuquerque, NM, USA.
| | - Arvind Caprihan
- The Mind Research Network (MRN), Albuquerque, New Mexico, United States of America
| | - Jingyu Liu
- The Mind Research Network (MRN), Albuquerque, New Mexico, United States of America
| | - Nora Perrone-Bizzozero
- Department of Neuroscience, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - Vince Calhoun
- Department of Neuroscience, University of New Mexico, Albuquerque, New Mexico, United States of America,The Mind Research Network (MRN), Albuquerque, New Mexico, United States of America,Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, New Mexico, United States of America
| |
Collapse
|
18
|
Metabotropic glutamate receptor 3 is associated with heroin dependence but not depression or schizophrenia in a Chinese population. PLoS One 2014; 9:e87247. [PMID: 24498053 PMCID: PMC3909071 DOI: 10.1371/journal.pone.0087247] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 12/19/2013] [Indexed: 01/08/2023] Open
Abstract
Metabotropic glutamate receptor subtype 3 (mGluR3, encoded by GRM3) plays important roles in the pathophysiology of schizophrenia, depression, and drug dependence. GRM3 polymorphisms were reported to be associated with prefrontal activity, cognitive shifting, and memory capability in healthy subjects, as well as susceptibility to schizophrenia and depression. The goal of this study was to replicate the association of GRM3 with schizophrenia and depression and to explore GRM3's potential association with heroin dependence (HD) in a Chinese population. Seventeen SNPs throughout the GRM3 gene were genotyped using MALDI-TOF within the MassARRAY system, and the allele and genotype distributions were compared between 619 healthy controls and 433 patients with schizophrenia, 409 patients with major depression, and 584 unrelated addicts. We found that GRM3 polymorphisms modulate the susceptibility to HD but do not significantly influence the risk for schizophrenia or depression. An increased risk of HD was significantly associated with the minor alleles of two GRM3 SNPs, including the T allele of rs274618 (Odds ratio (OR) = 1.631, 95% confidence interval (95%CI): 1.317-2.005), the T allele of rs274622 (OR = 1.652, 95% CI: 1.336-2.036), compared with the major alleles. The addicts carrying the minor allele of rs274618 or rs274622 had a shortened duration for transition from first use to dependence (DTFUD) in comparison to homozygote for major allele (P<0.0001 for each SNP using log rank test). Additionally, a 6-SNP haplotype within 5' region of the GRM3 including the minor alleles of the two aforementioned SNPs was significantly associated with an increased risk of HD (P = 0.00001, OR = 1.668, 95% CI: 1.335-2.084). Our data indicated that GRM3 polymorphisms do not contribute to genetic susceptibility to schizophrenia and depression, but they confer an increased risk of HD in a Chinese population.
Collapse
|
19
|
Morrow JA, Gilfillan R, Neale SA. Glutamatergic Approaches for the Treatment of Schizophrenia. DRUG DISCOVERY FOR PSYCHIATRIC DISORDERS 2012. [DOI: 10.1039/9781849734943-00056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Glutamate is the major excitatory neurotransmitter in the mammalian central nervous system and plays a key role in most aspects of normal brain function including cognition, learning and memory. Dysfunction of glutamatergic neurotransmission has been implicated in a number of neurological and psychiatric disorders with a growing body of evidence suggesting that hypofunction of glutamatergic neurotransmission via the N-methyl-d-aspartate (NMDA) receptor plays an important role in the pathophysiology of schizophrenia. It thus follows that potentiation of NMDA receptor function via pharmacological manipulation may provide therapeutic utility for the treatment of schizophrenia and a number of different approaches are currently being pursued by the pharmaceutical industry with this aim in mind. These include strategies that target the glycine/d-serine site of the NMDA receptor (glycine transporter GlyT1, d-serine transporter ASC-1 and d-amino acid oxidase (DAAO) inhibitors) together with those aimed at enhancing glutamatergic neurotransmission via modulation of AMPA receptor and metabotropic glutamate receptor function. Such efforts are now beginning to bear fruit with compounds such as the GlyT1 inhibitor RG1678 and mGlu2 agonist LY2140023 proving to have clinical meaningful effects in phase II clinical trials. While more studies are required to confirm long-term efficacy, functional outcome and safety in schizophrenic agents, these agents hold real promise for addressing unmet medical needs, in particular refractory negative and cognitive symptoms, not currently addressed by existing antipsychotic agents.
Collapse
Affiliation(s)
- John A. Morrow
- Neuroscience and Ophthalmology, Merck Research Laboratories 2015 Galloping Hill Road, Kenilworth, New Jersey 07033 USA
| | - Robert Gilfillan
- Discovery Chemistry, Merck Research Laboratories 770 Sumneytown Pike, West Point, Pennsylvania 19486 USA
| | - Stuart A. Neale
- Neurexpert Ltd Ground Floor, 2 Woodberry Grove, North Finchley, London, N12 0DR UK
| |
Collapse
|
20
|
Reynolds GP. The pharmacogenetics of symptom response to antipsychotic drugs. Psychiatry Investig 2012; 9:1-7. [PMID: 22396678 PMCID: PMC3285735 DOI: 10.4306/pi.2012.9.1.1] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Revised: 12/12/2011] [Accepted: 12/12/2011] [Indexed: 12/16/2022] Open
Abstract
Antipsychotic drugs are limited in their efficacy by the relatively poor response of negative and cognitive symptoms of schizophrenia as well as by the substantial variability in response between patients. Pharmacogenetic studies have sought to identify the genetic factors that underlie the individual variability in response to treatment, with a past emphasis on dopamine and serotonin receptors as candidate genes. Few studies have separated effects on positive and negative symptoms, despite the established differences in response to drug treatment between these syndromes. Where this has been done most findings are consistent with the conclusion that dopamine receptor polymorphisms relate to positive symptom response, while negative symptom improvement is influenced by polymorphisms of genes involved in 5-HT neurotransmission. A wide range of polymorphisms in other candidate genes have been investigated, with some positive findings in those genes associated with glutamatergic transmission and/or risk factors for schizophrenia. However, there remains a lack of good replicated findings; furthermore there is little evidence to support drug-specific genetic associations with treatment response. While most past studies focused on single candidate genes, technology now permits genome-wide association studies with response to antipsychotics. Although not without major limitations, these "hypothesis-free" approaches are beginning to identify further important risk factors for treatment response. Again there is little consistency between various studies, although some of the polymorphisms identified are in genes involved in neurodevelopment, which is increasingly being recognized as important in the pathophysiology of schizophrenia.
Collapse
Affiliation(s)
- Gavin P Reynolds
- Biomedical Research Centre, Sheffield Hallam University, Howard Street, Sheffield S1 1WB U.K.
| |
Collapse
|