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Lin CH, Lane HY. Sodium benzoate: A novel multi-target pharmaceutical approach to rescue clozapine-resistant schizophrenia. Schizophr Res 2024; 268:261-264. [PMID: 37230913 DOI: 10.1016/j.schres.2023.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 04/30/2023] [Accepted: 05/01/2023] [Indexed: 05/27/2023]
Affiliation(s)
- Chieh-Hsin Lin
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, No.123, Dapi Road, Kaohsiung 83301, Taiwan; School of Medicine, Chang Gung University, No.259, Wenhua 1st Road, Taoyuan 33302, Taiwan; Graduate Institute of Biomedical Sciences, China Medical University, No. 91, Xueshi Road, Taichung 404333, Taiwan
| | - Hsien-Yuan Lane
- Graduate Institute of Biomedical Sciences, China Medical University, No. 91, Xueshi Road, Taichung 404333, Taiwan; Department of Psychiatry & Brain Disease Research Center, China Medical University Hospital, No. 2, Yuh-Der Road, Taichung 404327, Taiwan; Department of Psychology, College of Medical and Health Sciences, Asia University, No. 500, Lioufeng Road, Taichung 41354, Taiwan.
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Vargas MH, Chávez J, Del-Razo-Rodríguez R, Muñoz-Perea C, Romo-Domínguez KJ, Báez-Saldaña R, Rumbo-Nava U, Guerrero-Zúñiga S. Glycine by enteral route does not improve major clinical outcomes in severe COVID-19: a randomized clinical pilot trial. Sci Rep 2024; 14:11566. [PMID: 38773199 PMCID: PMC11109244 DOI: 10.1038/s41598-024-62321-7] [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: 07/28/2023] [Accepted: 05/15/2024] [Indexed: 05/23/2024] Open
Abstract
There is a worrying scarcity of drug options for patients with severe COVID-19. Glycine possesses anti-inflammatory, cytoprotective, endothelium-protective, and platelet-antiaggregant properties, so its use in these patients seems promising. In this open label, controlled clinical trial, inpatients with severe COVID-19 requiring mechanical ventilation randomly received usual care (control group) or usual care plus 0.5 g/kg/day glycine by the enteral route (experimental group). Major outcomes included mortality, time to weaning from mechanical ventilation, total time on mechanical ventilation, and time from study recruitment to death. Secondary outcomes included laboratory tests and serum cytokines. Patients from experimental (n = 33) and control groups (n = 23) did not differ in basal characteristics. There were no differences in mortality (glycine group, 63.6% vs control group, 52.2%, p = 0.60) nor in any other major outcome. Glycine intake was associated with lower fibrinogen levels, either evaluated per week of follow-up (p < 0.05 at weeks 1, 2, and 4) or as weighted mean during the whole hospitalization (608.7 ± 17.7 mg/dl vs control 712.2 ± 25.0 mg/dl, p = 0.001), but did not modify any other laboratory test or cytokine concentration. In summary, in severe COVID-19 glycine was unable to modify major clinical outcomes, serum cytokines or most laboratory tests, but was associated with lower serum fibrinogen concentration.Registration: ClinicalTrials.gov NCT04443673, 23/06/2020.
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Affiliation(s)
- Mario H Vargas
- Departamento de Investigación en Hiperreactividad Bronquial, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Calzada de Tlalpan 4502, CP 14080, Ciudad de México, México.
| | - Jaime Chávez
- Departamento de Investigación en Hiperreactividad Bronquial, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Calzada de Tlalpan 4502, CP 14080, Ciudad de México, México
| | - Rosangela Del-Razo-Rodríguez
- Servicio Clínico de Neumología Pediátrica, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Ciudad de México, México
| | - Carolina Muñoz-Perea
- Servicio de Urgencias, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Ciudad de México, México
| | - Karina Julieta Romo-Domínguez
- Servicio de Urgencias, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Ciudad de México, México
- Servicio de Neumología, Hospital Infantil del Estado de Sonora, Hermosillo, Sonora, México
| | - Renata Báez-Saldaña
- Servicio Clínico 3, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Ciudad de México, México
| | - Uriel Rumbo-Nava
- Servicio Clínico 3, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Ciudad de México, México
| | - Selene Guerrero-Zúñiga
- Unidad de Medicina del Sueño, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Ciudad de México, México
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Soh J, Raventhiran S, Lee JH, Lim ZX, Goh J, Kennedy BK, Maier AB. The effect of glycine administration on the characteristics of physiological systems in human adults: A systematic review. GeroScience 2024; 46:219-239. [PMID: 37851316 PMCID: PMC10828290 DOI: 10.1007/s11357-023-00970-8] [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: 09/22/2023] [Accepted: 10/04/2023] [Indexed: 10/19/2023] Open
Abstract
Functional decline of physiological systems during ageing leads to age-related diseases. Dietary glycine increases healthy lifespan in model organisms and might decrease inflammation in humans, suggesting its geroprotective potential. This review summarises the evidence of glycine administration on the characteristics of eleven physiological systems in adult humans. Databases were searched using key search terms: 'glycine', 'adult', 'supplementation'/ 'administration'/ 'ingestion'/ 'treatment'. Glycine was administered to healthy and diseased populations (18 and 34 studies) for up to 14 days and 4 months, respectively. The nervous system demonstrated the most positive effects, including improved psychiatric symptoms from longer-term glycine administration in psychiatric populations. While longer-term glycine administration improved sleep in healthy populations, these studies had small sample sizes with a high risk of bias. Larger and long-term studies with more robust study designs in healthy populations to examine the effects of glycine administration on preventing, delaying or reversing the ageing process are warranted.
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Affiliation(s)
- Janjira Soh
- Centre for Healthy Longevity, National University Health System (NUHS), Singapore, Singapore
- Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
| | - Shivaanishaa Raventhiran
- Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
| | - Jasinda H Lee
- Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
| | - Zi Xiang Lim
- Centre for Healthy Longevity, National University Health System (NUHS), Singapore, Singapore
- Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
| | - Jorming Goh
- Centre for Healthy Longevity, National University Health System (NUHS), Singapore, Singapore
- Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
| | - Brian K Kennedy
- Centre for Healthy Longevity, National University Health System (NUHS), Singapore, Singapore
- Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
| | - Andrea B Maier
- Centre for Healthy Longevity, National University Health System (NUHS), Singapore, Singapore.
- Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore.
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore.
- Department of Human Movement Sciences, @AgeAmsterdam, Amsterdam Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Van Der Boechorstsraat 7, Amsterdam, 1081 BT, The Netherlands.
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Capuzzi E, Caldiroli A, Quitadamo C, Butturini F, Surace T, Clerici M, Buoli M. Novel pharmacotherapy targeting the positive symptoms of schizophrenia. Expert Opin Pharmacother 2023; 24:1623-1648. [PMID: 37401388 DOI: 10.1080/14656566.2023.2231346] [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: 04/28/2023] [Accepted: 06/27/2023] [Indexed: 07/05/2023]
Abstract
INTRODUCTION The severity of positive symptoms in schizophrenia is associated with poor prognosis. About one-third of schizophrenia patients partially respond to treatment with available antipsychotics. The purpose of the present manuscript is to provide an updated overview of novel pharmacotherapy targeting positive symptoms in schizophrenia. AREAS COVERED A comprehensive research on the main database sources (PubMed, PsychINFO, Isi Web of Knowledge, MEDLINE, and EMBASE) was performed to obtain original articles published till 31st January 2023 about new pharmacological strategies for the treatment of positive symptoms in schizophrenia. EXPERT OPINION The most promising compounds include: lamotrigine, pro-cognitive-compounds (donepezil - in the short term, idazoxan and piracetam) and drugs acting partially or totally outside the Central Nervous System (CNS) (anti-inflammatory drugs: celecoxib, methotrexate; cardiovascular compounds: L-theanine, mononitrate isosorbide, propentofylline, sodium nitroprusside; metabolic regulators: diazoxide, allopurinol; others: bexarotene, raloxifene [in women]). The effectiveness of the latter compounds indicates that other biological systems, such as immunity or metabolism can be object of future research to identify pharmacological targets for positive symptoms of schizophrenia. Mirtazapine could be useful for treating negative symptoms without increasing the risk of a worsening of delusions/hallucinations. Nevertheless, the lack of replication of studies prevents to draw definitive conclusions and future studies are needed to confirm the findings presented in this overview.
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Affiliation(s)
- Enrico Capuzzi
- Fondazione IRCCS, Department of Mental Health and Addiction, San Gerardo Dei Tintori, Monza, Italy
| | - Alice Caldiroli
- Fondazione IRCCS, Department of Mental Health and Addiction, San Gerardo Dei Tintori, Monza, Italy
| | - Cecilia Quitadamo
- Department of Medicine and Surgery, University of Milano Bicocca, Monza, MB, Italy
| | - Francesco Butturini
- Department of Medicine and Surgery, University of Milano Bicocca, Monza, MB, Italy
| | - Teresa Surace
- Fondazione IRCCS, Department of Mental Health and Addiction, San Gerardo Dei Tintori, Monza, Italy
| | - Massimo Clerici
- Fondazione IRCCS, Department of Mental Health and Addiction, San Gerardo Dei Tintori, Monza, Italy
- Department of Medicine and Surgery, University of Milano Bicocca, Monza, MB, Italy
| | - Massimiliano Buoli
- Department of Neurosciences and Mental Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
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Abstract
BACKGROUND Several augmentation strategies have been used to improve symptomatology in patients not adequately responding to clozapine. Several randomised controlled trials (RCTs) have evaluated the efficacy of different strategies to augment clozapine. This systematic review and meta-analysis reviewed the available RCTs that have evaluated the clinical efficacy of various pharmacological agents, non-pharmacological strategies (occupational therapy, cognitive behaviour therapy), and somatic treatment [electroconvulsive therapy (ECT), repetitive transcranial magnetic stimulation, etc.)] as augmenting agents to clozapine. METHODS Data were extracted using standard procedures, and risk of bias was evaluated. Effect sizes were computed for the individual studies. RESULTS Forty-five clinical trials were evaluated. The pooled effect size for various antipsychotic medications was 0.103 (95% CI: 0.288-0.493, p < 0.001); when the effect size was evaluated for specific antipsychotics for which more than one trial was available, the effect size for risperidone was -0.27 and that for aripiprazole was 0.57. The effect size for lamotrigine was 0.145, and that for topiramate was 0.392. The effect size for ECT was 0.743 (CI: 0.094-1.392). Risk of bias was low (mean Jadad score - 3.93). Largest effect sizes were seen for mirtazapine (effect size of 5.265). Most of the studies can be considered underpowered and limited by small sample sizes. CONCLUSIONS To conclude, based on the findings of the present systematic review and meta-analysis, it can be said that compared to other treatment strategies, clozapine non-responsive patients respond maximum to mirtazapine followed by ECT.
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Glutamatergic dysfunction in Schizophrenia. Transl Psychiatry 2022; 12:500. [PMID: 36463316 PMCID: PMC9719533 DOI: 10.1038/s41398-022-02253-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 11/05/2022] [Accepted: 11/09/2022] [Indexed: 12/04/2022] Open
Abstract
The NMDA-R hypofunction model of schizophrenia started with the clinical observation of the precipitation of psychotic symptoms in patients with schizophrenia exposed to PCP or ketamine. Healthy volunteers exposed to acute low doses of ketamine experienced mild psychosis but also negative and cognitive type symptoms reminiscent of the full clinical picture of schizophrenia. In rodents, acute systemic ketamine resulted in a paradoxical increase in extracellular frontal glutamate as well as of dopamine. Similar increase in prefrontal glutamate was documented with acute ketamine in healthy volunteers with 1H-MRS. Furthermore, sub-chronic low dose PCP lead to reductions in frontal dendritic tree density in rodents. In post-mortem ultrastructural studies in schizophrenia, a broad reduction in dendritic complexity and somal volume of pyramidal cells has been repeatedly described. This most likely accounts for the broad, subtle progressive cortical thinning described with MRI in- vivo. Additionally, prefrontal reductions in the obligatory GluN1 subunit of the NMDA-R has been repeatedly found in post-mortem tissue. The vast 1H-MRS literature in schizophrenia has documented trait-like small increases in glutamate concentrations in striatum very early in the illness, before antipsychotic treatment (the same structure where increased pre-synaptic release of dopamine has been reported with PET). The more recent genetic literature has reliably detected very small risk effects for common variants involving several glutamate-related genes. The pharmacological literature has followed two main tracks, directly informed by the NMDA-R hypo model: agonism at the glycine site (as mostly add-on studies targeting negative and cognitive symptoms); and pre-synaptic modulation of glutamatergic release (as single agents for acute psychosis). Unfortunately, both approaches have failed so far. There is little doubt that brain glutamatergic abnormalities are present in schizophrenia and that some of these are related to the etiology of the illness. The genetic literature directly supports a non- specific etiological role for glutamatergic dysfunction. Whether NMDA-R hypofunction as a specific mechanism accounts for any important component of the illness is still not evident. However, a glutamatergic model still has heuristic value to guide future research in schizophrenia. New tools to jointly examine brain glutamatergic, GABA-ergic and dopaminergic systems in-vivo, early in the illness, may lay the ground for a next generation of clinical trials that go beyond dopamine D2 blockade.
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de Bartolomeis A, Vellucci L, Austin MC, De Simone G, Barone A. Rational and Translational Implications of D-Amino Acids for Treatment-Resistant Schizophrenia: From Neurobiology to the Clinics. Biomolecules 2022; 12:biom12070909. [PMID: 35883465 PMCID: PMC9312470 DOI: 10.3390/biom12070909] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 06/25/2022] [Accepted: 06/26/2022] [Indexed: 12/13/2022] Open
Abstract
Schizophrenia has been conceptualized as a neurodevelopmental disorder with synaptic alterations and aberrant cortical–subcortical connections. Antipsychotics are the mainstay of schizophrenia treatment and nearly all share the common feature of dopamine D2 receptor occupancy, whereas glutamatergic abnormalities are not targeted by the presently available therapies. D-amino acids, acting as N-methyl-D-aspartate receptor (NMDAR) modulators, have emerged in the last few years as a potential augmentation strategy in those cases of schizophrenia that do not respond well to antipsychotics, a condition defined as treatment-resistant schizophrenia (TRS), affecting almost 30–40% of patients, and characterized by serious cognitive deficits and functional impairment. In the present systematic review, we address with a direct and reverse translational perspective the efficacy of D-amino acids, including D-serine, D-aspartate, and D-alanine, in poor responders. The impact of these molecules on the synaptic architecture is also considered in the light of dendritic spine changes reported in schizophrenia and antipsychotics’ effect on postsynaptic density proteins. Moreover, we describe compounds targeting D-amino acid oxidase and D-aspartate oxidase enzymes. Finally, other drugs acting at NMDAR and proxy of D-amino acids function, such as D-cycloserine, sarcosine, and glycine, are considered in the light of the clinical burden of TRS, together with other emerging molecules.
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Affiliation(s)
- Andrea de Bartolomeis
- Laboratory of Translational and Molecular Psychiatry and Unit of Treatment-Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Sciences and Dentistry, University of Naples Federico II, 80131 Naples, Italy; (L.V.); (G.D.S.); (A.B.)
- Correspondence: ; Tel.: +39-081-7463673 or +39-081-7463884 or +39-3662745592; Fax: +39-081-7462644
| | - Licia Vellucci
- Laboratory of Translational and Molecular Psychiatry and Unit of Treatment-Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Sciences and Dentistry, University of Naples Federico II, 80131 Naples, Italy; (L.V.); (G.D.S.); (A.B.)
| | - Mark C. Austin
- Clinical Psychopharmacology Program, College of Pharmacy, Idaho State University, Pocatello, ID 83209, USA;
| | - Giuseppe De Simone
- Laboratory of Translational and Molecular Psychiatry and Unit of Treatment-Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Sciences and Dentistry, University of Naples Federico II, 80131 Naples, Italy; (L.V.); (G.D.S.); (A.B.)
| | - Annarita Barone
- Laboratory of Translational and Molecular Psychiatry and Unit of Treatment-Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Sciences and Dentistry, University of Naples Federico II, 80131 Naples, Italy; (L.V.); (G.D.S.); (A.B.)
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Strzelecki D, Kotlicka-Antczak M, Kaczmarek B, Jerczyńska H, Wysokiński A. Serum levels of neuropeptide Y in patients with chronic schizophrenia during treatment augmentation with sarcosine (results of the double-blind randomized controlled PULSAR study). Hum Psychopharmacol 2021; 36:e2770. [PMID: 33245168 DOI: 10.1002/hup.2770] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 10/18/2020] [Accepted: 11/11/2020] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Modulation of glutamatergic neurotransmission in schizophrenia by sarcosine leads to a reduction in primary negative symptoms, while its metabolic profile is safe. In order to extend research in the area, we assessed serum levels of neuropeptide Y (NPY), a hypothalamic hormone related to anxiety and depression, also involved in mechanisms inducing weight gain. Additionally, we analyzed associations between NPY concentrations and its changes with severity of symptoms and metabolic parameters. METHODS A prospective 6-month, randomized, double-blind placebo-controlled trial was completed by 57 subjects with chronic schizophrenia with predominant negative symptoms and stable antipsychotic treatment. The participants received 2 g of sarcosine (n = 28) or placebo (n = 29) daily. We assessed serum NPY concentrations and severity of symptoms (with the Positive and Negative Syndrome Scale [PANSS] and Calgary Depression Scale for Schizophrenia) at the beginning of the study, after 6 weeks and 6 months. RESULTS Sarcosine did not affect NPY levels in all time points. The highest decrease in NPY concentrations was observed in the subjects who were initially depressed, who became euthymic at the last visit. We noticed an improvement in the total PANSS score, and negative symptom and general psychopathology subscales in the sarcosine group, however, without any correlation with NPY levels. CONCLUSION The use of sarcosine does not change NPY levels. Peripheral NPY concentrations may be related to depressive symptoms in schizophrenia.
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Affiliation(s)
- Dominik Strzelecki
- Department of Affective and Psychotic Disorders, Medical University of Lodz, Łódź, Poland
| | | | - Bartosz Kaczmarek
- Department of Affective and Psychotic Disorders, Medical University of Lodz, Łódź, Poland
| | - Hanna Jerczyńska
- Central Scientific Laboratory (CoreLab), Medical University of Lodz, Łódź, Poland
| | - Adam Wysokiński
- Department of Old Age Psychiatry and Psychotic Disorders, Medical University of Lodz, Łódź, Poland
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Goh KK, Wu TH, Chen CH, Lu ML. Efficacy of N-methyl- D-aspartate receptor modulator augmentation in schizophrenia: A meta-analysis of randomised, placebo-controlled trials. J Psychopharmacol 2021; 35:236-252. [PMID: 33406959 DOI: 10.1177/0269881120965937] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND Dysfunction of the N-methyl-D-aspartate glutamate receptor is involved in the putative pathology of schizophrenia. There is growing interest in the potential of N-methyl-D-aspartate receptor modulators to improve the symptoms of schizophrenia, but the evidence for the use of glutamatergic agents for augmenting schizophrenia remains inconclusive. AIMS We conducted a meta-analysis to test the efficacy and safety of N-methyl-D-aspartate receptor modulator supplements in patients with schizophrenia. METHODS Following a systemic search in MEDLINE, Embase, Cochrane and Scopus, 40 double-blinded, randomised, placebo-controlled trials involving 4937 patients with schizophrenia were included in this meta-analysis. The change in the severity of symptoms among patients with schizophrenia was defined as the primary outcome, whereas the safety profiles of the intervention, including the discontinuation rate and adverse events, were defined as secondary outcomes. RESULTS When added to antipsychotic treatments, N-methyl-D-aspartate receptor modulators improved multiple schizophrenia symptoms, particularly negative symptoms, and had satisfactory side effects and safety profile. Among the seven glutamatergic agents analysed, glycine, D-serine and sarcosine had better treatment profiles than other agents, and NMDA receptor co-agonists, as a group, provided a reduction in schizophrenia symptoms compared to antipsychotic treatments without supplementation. Augmentation with N-methyl-D-aspartate receptor modulators was only effective among patients treated with antipsychotics other than clozapine. CONCLUSIONS The results indicate that N-methyl-D-aspartate receptor modulators, particularly with glycine, D-serine and sarcosine, are more beneficial than the placebo in treating schizophrenia, and the effects extended to both positive and negative symptoms, when augmented with antipsychotics other than clozapine.
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Affiliation(s)
- Kah Kheng Goh
- Department of Psychiatry, Wan-Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Psychiatric Research Center, Wan-Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Tzu-Hua Wu
- Psychiatric Research Center, Wan-Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Clinical Pharmacy, School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan
| | - Chun-Hsin Chen
- Department of Psychiatry, Wan-Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Psychiatric Research Center, Wan-Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Tapei, Taiwan
| | - Mong-Liang Lu
- Department of Psychiatry, Wan-Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Psychiatric Research Center, Wan-Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Tapei, Taiwan
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Campana M, Falkai P, Siskind D, Hasan A, Wagner E. Characteristics and definitions of ultra-treatment-resistant schizophrenia - A systematic review and meta-analysis. Schizophr Res 2021; 228:218-226. [PMID: 33454644 DOI: 10.1016/j.schres.2020.12.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 11/17/2020] [Accepted: 12/14/2020] [Indexed: 02/06/2023]
Abstract
OBJECTIVE The aim of this systematic review and meta-analysis was to characterize ultra-treatment-resistant Schizophrenia also known as clozapine-resistant schizophrenia (CRS) patients across clozapine combination and augmentation trials through demographic and clinical baseline data. Furthermore, we investigated the variability and consistency in CRS definitions between studies. METHODS Systematic searches of articles indexed in PubMed, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL) and PsycINFO were conducted in March 2020. 1541 randomized and non-randomized clinical trials investigating pharmacological and non-pharmacological clozapine add-on strategies were screened and a total of 71 studies were included. The primary outcome was the overall symptom score at baseline, measured with Positive and Negative Syndrome Scale (PANSS) total or Brief Psychiatric Rating Scale (BPRS) total scores. RESULTS Data from 2731 patients were extracted. Patients were overall moderately ill with a mean PANSS total score at baseline of 79.16 (±7.52), a mean duration of illness of 14.64 (±4.14) years with a mean clozapine dose of 436.94 (±87.47) mg/day. Illness severity data were relatively homogenous among patients independently of the augmentation strategy involved, although stark geographical differences were found. Overall, studies showed a large heterogeneity of CRS definitions and insufficient guidelines implementation. CONCLUSIONS This first meta-analysis characterizing CRS patients and comparing CRS definitions revealed a lack of consistent implementation of a CRS definition from guidelines into clinical trials, compromising the replicability of the results and their applicability in clinical practice. We offer a new score modeled on a best practice definition to help future trials increase their reliability.
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Affiliation(s)
- Mattia Campana
- Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany.
| | - Peter Falkai
- Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany
| | - Dan Siskind
- School of Medicine, University of Queensland, Brisbane, Australia; Metro South Addiction and Mental Health Service, Brisbane, Australia
| | - Alkomiet Hasan
- Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany; Department of Psychiatry, Psychotherapy and Psychosomatics of the University Augsburg, Augsburg, Germany
| | - Elias Wagner
- Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany
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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: 16] [Impact Index Per Article: 5.3] [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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12
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Hons J, Zirko R, Vasatova M, Doubek P, Klimova B, Masopust J, Valis M, Kuca K. Impairment of Executive Functions Associated With Lower D-Serine Serum Levels in Patients With Schizophrenia. Front Psychiatry 2021; 12:514579. [PMID: 33854443 PMCID: PMC8039447 DOI: 10.3389/fpsyt.2021.514579] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 02/16/2021] [Indexed: 12/01/2022] Open
Abstract
A core symptom that is frequently linked with dysregulation of glutamatergic neurotransmission in regard to schizophrenia is impairment or damage of executive functioning as a component of cognitive deficiency. The amino acid D-serine plays the role of an endogenous coagonist at the glutamatergic N-methyl-D-aspartate (NMDA) receptor glycine modulatory site. Considerably reduced serum levels of D-serine were found in patients suffering from schizophrenia compared with healthy control participants. An increase in D-serine led to augmented cognitive functionality in patients suffering from schizophrenia who were undergoing clinical trials and given the treatment of first- and second-generation antipsychotics. The study proposed the hypothesis that the D-serine blood serum levels may be linked with the extent of executive functionality in those suffering from the mental illness in question. For the purpose of examining executive function in such patients, the Rey-Osterrieth Complex Figure, Trail Making, and Wisconsin Card Sorting tests were applied (n = 50). High-performance liquid chromatography was used to gauge the total serine and D-serine levels. The extent of damage was examined through neuropsychological tests and was found to be considerably linked to D-serine serum level and the D-serine/total serine ratio (p < 0.05) in the sample being considered. A lower average serum level of D-serine and lower D-serine/total serine ratio were observed in participants with the worst performance compared with those displaying the best performance-this was true when the patients were split into quartile groups based on their results (p < 0.05). The findings of modified D-serine serum levels and the D-serine/total serine ratio linked to the extent of damage in executive functioning indicate that serine metabolism that is coresponsible for NMDA receptor dysfunction has been changed.
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Affiliation(s)
- Jaromir Hons
- Center for Psychiatry, Regional Hospital Liberec, Liberec, Czechia.,Institute of Health Studies, Technical University of Liberec, Liberec, Czechia
| | - Rastislav Zirko
- Department of Psychiatry, Faculty of Medicine in Hradec Kralove, University Hospital Hradec Kralove and Charles University in Prague, Hradec Kralove, Czechia
| | - Martina Vasatova
- Institute of Clinical Biochemistry and Diagnostics, University Hospital Hradec Kralove and Charles University in Prague, Hradec Kralove, Czechia
| | - Pavel Doubek
- Department of Psychiatry, 1st Faculty of Medicine, General Teaching Hospital and Charles University in Prague, Prague, Czechia
| | - Blanka Klimova
- Department of Neurology, Faculty of Medicine in Hradec Kralove, University Hospital Hradec Kralove and Charles University in Prague, Hradec Kralove, Czechia
| | - Jiri Masopust
- Department of Psychiatry, Faculty of Medicine in Hradec Kralove, University Hospital Hradec Kralove and Charles University in Prague, Hradec Kralove, Czechia.,Department of Neurology, Faculty of Medicine in Hradec Kralove, University Hospital Hradec Kralove and Charles University in Prague, Hradec Kralove, Czechia
| | - Martin Valis
- Department of Neurology, Faculty of Medicine in Hradec Kralove, University Hospital Hradec Kralove and Charles University in Prague, Hradec Kralove, Czechia
| | - Kamil Kuca
- Biomedical Research Center, University Hospital Hradec Kralove, Hradec Kralove, Czechia.,Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czechia
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13
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Potkin SG, Kane JM, Correll CU, Lindenmayer JP, Agid O, Marder SR, Olfson M, Howes OD. The Neurobiology of Treatment-Resistant Schizophrenia: Paths to Antipsychotic Resistance and A Roadmap for Future Research. FOCUS: JOURNAL OF LIFE LONG LEARNING IN PSYCHIATRY 2020; 18:456-465. [PMID: 33343259 DOI: 10.1176/appi.focus.18309] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
(Reprinted with permission from NPJ Schizophrenia (2020) 6:1).
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14
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Oh SJ, Fan X. Current understanding on the role of nitric oxide and therapeutic potential of NO supplementation in schizophrenia. Schizophr Res 2020; 222:23-30. [PMID: 32475621 DOI: 10.1016/j.schres.2020.05.050] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 05/05/2020] [Accepted: 05/18/2020] [Indexed: 10/24/2022]
Affiliation(s)
- SeungJu Jackie Oh
- University of Massachusetts Medical School, Worcester, MA, 01655, United States of America
| | - Xiaoduo Fan
- UMass Memorial Health Care, University of Massachusetts Medical School, United States of America.
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15
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Potkin SG, Kane JM, Correll CU, Lindenmayer JP, Agid O, Marder SR, Olfson M, Howes OD. The neurobiology of treatment-resistant schizophrenia: paths to antipsychotic resistance and a roadmap for future research. NPJ SCHIZOPHRENIA 2020; 6:1. [PMID: 31911624 PMCID: PMC6946650 DOI: 10.1038/s41537-019-0090-z] [Citation(s) in RCA: 142] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 10/31/2019] [Indexed: 01/13/2023]
Abstract
Treatment-resistant schizophrenia (TRS), the persistence of positive symptoms despite ≥2 trials of adequate dose and duration of antipsychotic medication with documented adherence, is a serious clinical problem with heterogeneous presentations. TRS can vary in its onset (at the first episode of psychosis or upon relapse), in its severity, and in the response to subsequent therapeutic interventions (i.e., clozapine, electroconvulsive therapy). The heterogeneity of TRS indicates that the underlying neurobiology of TRS may differ not only from treatment-responsive schizophrenia but also among patients with TRS. Several hypotheses have been proposed for the neurobiological mechanisms underlying TRS, including dopamine supersensitivity, hyperdopaminergic and normodopaminergic subtypes, glutamate dysregulation, inflammation and oxidative stress, and serotonin dysregulation. Research supporting these hypotheses is limited in part by variations in the criteria used to define TRS, as well as by the biological and clinical heterogeneity of TRS. Clinical trial designs for new treatments should be informed by this heterogeneity, and further clinical research is needed to more clearly understand the underlying neurobiology of TRS and to optimize treatment for patients with TRS.
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Affiliation(s)
| | - John M Kane
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Department of Psychiatry and Molecular Medicine, Hempstead, NY, USA
- The Zucker Hillside Hospital, Glen Oaks, NY, USA
- The Feinstein Institute for Medical Research, Psychiatric Neuroscience Center of Excellence, Manhasset, NY, USA
| | - Christoph U Correll
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Department of Psychiatry and Molecular Medicine, Hempstead, NY, USA
- The Zucker Hillside Hospital, Glen Oaks, NY, USA
- The Feinstein Institute for Medical Research, Psychiatric Neuroscience Center of Excellence, Manhasset, NY, USA
- Charité Universitätsmedizin, Department of Child and Adolescent Psychiatry, Berlin, Germany
| | | | - Ofer Agid
- Centre for Addiction and Mental Health, Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Stephen R Marder
- The Semel Institute for Neuroscience at UCLA, Los Angeles, CA, USA
- The VA Desert Pacific Mental Illness Research, Education, and Clinical Center, Los Angeles, CA, USA
| | - Mark Olfson
- Department of Psychiatry, Columbia University Irving Medical Center, New York, NY, USA
| | - Oliver D Howes
- King's College, London, UK.
- MRC London Institute of Medical Sciences, Imperial College, London, UK.
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16
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Bodkin JA, Coleman MJ, Godfrey LJ, Carvalho CM, Morgan CJ, Suckow RF, Anderson T, Ongur D, Kaufman MJ, Lewandowski KE, Siegel AJ, Waldstreicher E, Grochowski CM, Javitt DC, Rujescu D, Hebbring S, Weinshilboum R, Rodriguez SB, Kirchhoff C, Visscher T, Vuckovic A, Fialkowski A, McCarthy S, Malhotra D, Sebat J, Goff DC, Hudson JI, Lupski JR, Coyle JT, Rudolph U, Levy DL. Targeted Treatment of Individuals With Psychosis Carrying a Copy Number Variant Containing a Genomic Triplication of the Glycine Decarboxylase Gene. Biol Psychiatry 2019; 86:523-535. [PMID: 31279534 PMCID: PMC6745274 DOI: 10.1016/j.biopsych.2019.04.031] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 04/17/2019] [Accepted: 04/17/2019] [Indexed: 02/08/2023]
Abstract
BACKGROUND The increased mutational burden for rare structural genomic variants in schizophrenia and other neurodevelopmental disorders has so far not yielded therapies targeting the biological effects of specific mutations. We identified two carriers (mother and son) of a triplication of the gene encoding glycine decarboxylase, GLDC, presumably resulting in reduced availability of the N-methyl-D-aspartate receptor coagonists glycine and D-serine and N-methyl-D-aspartate receptor hypofunction. Both carriers had a diagnosis of a psychotic disorder. METHODS We carried out two double-blind, placebo-controlled clinical trials of N-methyl-D-aspartate receptor augmentation of psychotropic drug treatment in these two individuals. Glycine was used in the first clinical trial, and D-cycloserine was used in the second one. RESULTS Glycine or D-cycloserine augmentation of psychotropic drug treatment each improved psychotic and mood symptoms in placebo-controlled trials. CONCLUSIONS These results provide two independent proof-of-principle demonstrations of symptom relief by targeting a specific genotype and explicitly link an individual mutation to the pathophysiology of psychosis and treatment response.
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Affiliation(s)
| | | | | | | | | | | | | | - Dost Ongur
- McLean Hospital, Belmont, MA.,Harvard Medical School, Boston, MA
| | - Marc J. Kaufman
- McLean Hospital, Belmont, MA.,Harvard Medical School, Boston, MA
| | | | - Arthur J. Siegel
- McLean Hospital, Belmont, MA.,Harvard Medical School, Boston, MA
| | | | | | - Daniel C. Javitt
- Columbia University Medical Center, New York, NY.,Nathan Kline Institute, Orangeburg, NY
| | - Dan Rujescu
- Department of Psychiatry, Psychotherapy, and Psychosomatics, Martin Luther University of Halle-Wittenberg, Halle, Germany
| | - Scott Hebbring
- Center for Human Genetics, Marshfield Clinic Research Institute, Marshfield, WI
| | | | | | | | | | | | | | | | | | | | - Donald C. Goff
- Nathan Kline Institute, Orangeburg, NY.,Department of Psychiatry, New York University Langone Medical Center, New York, NY
| | - James I. Hudson
- McLean Hospital, Belmont, MA.,Harvard Medical School, Boston, MA
| | | | - Joseph T. Coyle
- McLean Hospital, Belmont, MA.,Harvard Medical School, Boston, MA
| | - Uwe Rudolph
- McLean Hospital, Belmont, MA.,Harvard Medical School, Boston, MA
| | - Deborah L. Levy
- McLean Hospital, Belmont, MA.,Harvard Medical School, Boston, MA
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17
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Zhand N, Attwood DG, Harvey PD. Glutamate modulators for treatment of schizophrenia. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.pmip.2019.02.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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18
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19
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The past and future of novel, non-dopamine-2 receptor therapeutics for schizophrenia: A critical and comprehensive review. J Psychiatr Res 2019; 108:57-83. [PMID: 30055853 DOI: 10.1016/j.jpsychires.2018.07.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 06/13/2018] [Accepted: 07/12/2018] [Indexed: 01/28/2023]
Abstract
Since the discovery of chlorpromazine in the 1950's, antipsychotic drugs have been the cornerstone of treatment of schizophrenia, and all attenuate dopamine transmission at the dopamine-2 receptor. Drug development for schizophrenia since that time has led to improvements in side effects and tolerability, and limited improvements in efficacy, with the exception of clozapine. However, the reasons for clozapine's greater efficacy remain unclear, despite the great efforts and resources invested therewith. We performed a comprehensive review of the literature to determine the fate of previously tested, non-dopamine-2 receptor experimental treatments. Overall we included 250 studies in the review from the period 1970 to 2017 including treatments with glutamatergic, serotonergic, cholinergic, neuropeptidergic, hormone-based, dopaminergic, metabolic, vitamin/naturopathic, histaminergic, infection/inflammation-based, and miscellaneous mechanisms. Despite there being several promising targets, such as allosteric modulation of the NMDA and α7 nicotinic receptors, we cannot confidently state that any of the mechanistically novel experimental treatments covered in this review are definitely effective for the treatment of schizophrenia and ready for clinical use. We discuss potential reasons for the relative lack of progress in developing non-dopamine-2 receptor treatments for schizophrenia and provide recommendations for future efforts pursuing novel drug development for schizophrenia.
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20
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Strzelecki D, Urban-Kowalczyk M, Wysokiński A. Serum levels of TNF-alpha in patients with chronic schizophrenia during treatment augmentation with sarcosine (results of the PULSAR study). Psychiatry Res 2018; 268:447-453. [PMID: 30130712 DOI: 10.1016/j.psychres.2018.08.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 05/30/2018] [Accepted: 08/01/2018] [Indexed: 12/16/2022]
Abstract
Sarcosine, glycine transporter inhibitor, increases glycine levels around NMDA receptor, improving primary negative symptoms of schizophrenia. The aim of our study was to find a potential relationship between initial TNF-alpha level, its changes and schizophrenia symptoms severity, resulting from adding sarcosine to a stable antipsychotic treatment. Sixty subjects with stable schizophrenia were randomized to receive either 2 g of sarcosine or placebo and completed a 6-month, double blind, placebo-controlled study. Three patients on sarcosine and one taking placebo did not complete TNF-alpha tests, planned at the beginning, after 6 weeks and after 6 months. For clinical assessments we used PANSS and CDSS scales. No changes in TNF-alpha serum concentrations in both groups at any time-points was noted. The sarcosine group achieved significant improvement in negative symptoms, general psychopathology and total PANSS score group, however without any significant correlations between TNF-alpha levels and PANSS scores in all assessments. Positive correlations between TNF-alpha levels and CDSS score were found in the placebo group and total study group. Initial TNF-alpha concentrations cannot be used as a predictor of the improvement resulting from adding sarcosine. Sarcosine does not significantly affect TNF-alpha levels. TNF-alpha may be involved in mechanisms related to depressive symptomatology in schizophrenia.
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Affiliation(s)
- Dominik Strzelecki
- Department of Affective and Psychotic Disorders, Central Clinical Hospital, Medical University of Łódź, ul. Czechosłowacka 8/10, 92-216, Łódź, Poland.
| | - Małgorzata Urban-Kowalczyk
- Department of Affective and Psychotic Disorders, Central Clinical Hospital, Medical University of Łódź, ul. Czechosłowacka 8/10, 92-216, Łódź, Poland
| | - Adam Wysokiński
- Department of Old Age Psychiatry and Psychotic Disorders, Medical University of Łódź, Łódź, Poland
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21
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Lin CH, Lin CH, Chang YC, Huang YJ, Chen PW, Yang HT, Lane HY. Sodium Benzoate, a D-Amino Acid Oxidase Inhibitor, Added to Clozapine for the Treatment of Schizophrenia: A Randomized, Double-Blind, Placebo-Controlled Trial. Biol Psychiatry 2018; 84:422-432. [PMID: 29397899 DOI: 10.1016/j.biopsych.2017.12.006] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 12/06/2017] [Accepted: 12/08/2017] [Indexed: 12/15/2022]
Abstract
BACKGROUND Clozapine is the last-line antipsychotic agent for refractory schizophrenia. To date, there is no convincing evidence for augmentation on clozapine. Activation of N-methyl-D-aspartate receptors, including inhibition of D-amino acid oxidase that may metabolize D-amino acids, has been reported to be beneficial for patients receiving antipsychotics other than clozapine. This study aimed to examine the efficacy and safety of a D-amino acid oxidase inhibitor, sodium benzoate, for schizophrenia patients who had poor response to clozapine. METHODS We conducted a randomized, double-blind, placebo-controlled trial. Sixty schizophrenia inpatients that had been stabilized with clozapine were allocated into three groups for 6 weeks' add-on treatment of 1 g/day sodium benzoate, 2 g/day sodium benzoate, or placebo. The primary outcome measures were Positive and Negative Syndrome Scale (PANSS) total score, Scale for the Assessment of Negative Symptoms, Quality of Life Scale, and Global Assessment of Functioning. Side effects and cognitive functions were also measured. RESULTS Both doses of sodium benzoate produced better improvement than placebo in the Scale for the Assessment of Negative Symptoms. The 2 g/day sodium benzoate also produced better improvement than placebo in PANSS-total score, PANSS-positive score, and Quality of Life Scale. Sodium benzoate was well tolerated without evident side effects. The changes of catalase, an antioxidant, were different among the three groups and correlated with the improvement of PANSS-total score and PANSS-positive score in the sodium benzoate group. CONCLUSIONS Sodium benzoate adjuvant therapy improved symptomatology of patients with clozapine-resistant schizophrenia. Further studies are warranted to elucidate the optimal dose and treatment duration as well as the mechanisms of sodium benzoate for clozapine-resistant schizophrenia.
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Affiliation(s)
- Chieh-Hsin Lin
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan; Center for General Education, Cheng Shiu University, Kaohsiung, Taiwan; Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan
| | - Ching-Hua Lin
- Department of Adult Psychiatry, Kaohsiung Municipal Kai-Syuan Psychiatric Hospital, Kaohsiung, Taiwan
| | - Yue-Cune Chang
- Department of Mathematics, Tamkang University, Taipei, Taiwan
| | - Yu-Jhen Huang
- Department of Psychiatry, China Medical University Hospital, Taichung, Taiwan
| | - Po-Wei Chen
- Department of Psychiatry, Taichung Chin-Ho Hospital, Taichung, Taiwan
| | - Hui-Ting Yang
- Department of Nutrition, China Medical University, Taichung, Taiwan
| | - Hsien-Yuan Lane
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan; Department of Psychiatry, China Medical University Hospital, Taichung, Taiwan.
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22
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Siskind DJ, Lee M, Ravindran A, Zhang Q, Ma E, Motamarri B, Kisely S. Augmentation strategies for clozapine refractory schizophrenia: A systematic review and meta-analysis. Aust N Z J Psychiatry 2018; 52:751-767. [PMID: 29732913 DOI: 10.1177/0004867418772351] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Although clozapine is the most effective medication for treatment refractory schizophrenia, only 40% of people will meet response criteria. We therefore undertook a systematic review and meta-analysis of global literature on clozapine augmentation strategies. METHODS We systematically reviewed PubMed, PsycInfo, Embase, Cochrane Database, Chinese Biomedical Literature Service System and China Knowledge Resource Integrated Database for randomised control trials of augmentation strategies for clozapine resistant schizophrenia. We undertook pairwise meta-analyses of within-class interventions and, where possible, frequentist mixed treatment comparisons to differentiate treatment effectiveness Results: We identified 46 studies of 25 interventions. On pairwise meta-analyses, the most effective augmentation agents for total psychosis symptoms were aripiprazole (standardised mean difference: 0.48; 95% confidence interval: -0.89 to -0.07) fluoxetine (standardised mean difference: 0.73; 95% confidence interval: -0.97 to -0.50) and, sodium valproate (standardised mean difference: 2.36 95% confidence interval: -3.96 to -0.75). Memantine was effective for negative symptoms (standardised mean difference: -0.56 95% confidence interval: -0.93 to -0.20). However, many of these results included poor-quality studies. Single studies of certain antipsychotics (penfluridol), antidepressants (paroxetine, duloxetine), lithium and Ginkgo biloba showed potential, while electroconvulsive therapy was highly promising. Mixed treatment comparisons were only possible for antipsychotics, and these gave similar results to the pairwise meta-analyses. CONCLUSIONS On the basis of the limited data available, the best evidence is for the use of aripiprazole, fluoxetine and sodium valproate as augmentation agents for total psychosis symptoms and memantine for negative symptoms. However, these conclusions are tempered by generally short follow-up periods and poor study quality.
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Affiliation(s)
- Dan J Siskind
- 1 Addiction and Mental Health Services and MIRT, Metro South Health, Brisbane, QLD, Australia.,2 MIRT, Woolloongabba Community Health Centre, Metro South Health, Woolloongabba, QLD, Australia.,3 School of Medicine, The University of Queensland, Brisbane, QLD, Australia
| | - Michael Lee
- 3 School of Medicine, The University of Queensland, Brisbane, QLD, Australia
| | - Arul Ravindran
- 3 School of Medicine, The University of Queensland, Brisbane, QLD, Australia
| | - Qichen Zhang
- 3 School of Medicine, The University of Queensland, Brisbane, QLD, Australia
| | - Evelyn Ma
- 3 School of Medicine, The University of Queensland, Brisbane, QLD, Australia
| | - Balaji Motamarri
- 1 Addiction and Mental Health Services and MIRT, Metro South Health, Brisbane, QLD, Australia.,3 School of Medicine, The University of Queensland, Brisbane, QLD, Australia
| | - Steve Kisely
- 1 Addiction and Mental Health Services and MIRT, Metro South Health, Brisbane, QLD, Australia.,3 School of Medicine, The University of Queensland, Brisbane, QLD, Australia
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23
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Strzelecki D, Urban-Kowalczyk M, Wysokiński A. Serum levels of interleukin 6 in schizophrenic patients during treatment augmentation with sarcosine (results of the PULSAR study). Hum Psychopharmacol 2018; 33:e2652. [PMID: 29417623 DOI: 10.1002/hup.2652] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 10/10/2017] [Accepted: 01/02/2018] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Augmentation of sarcosine, a natural inhibitor of the glycine transporter type I, normalizes glutamatergic neurotransmission, having beneficial impact on primary negative symptoms in schizophrenia and may also influence immune system and interleukin 6 (IL-6) levels. AIM Finding a relationship between initial IL-6 serum concentrations or its changes and severity of symptoms as a result of sarcosine addition to stable antipsychotic treatment. METHOD Fifity-eight individuals with schizophrenia with predominantly negative symptoms completed a 6-month randomized, double-blind placebo-controlled prospective study. Patients received 2 g of sarcosine (n = 29) or placebo (n = 30) daily per os. We measured IL-6 levels and severity of symptoms at the beginning, after 6 weeks and 6 months. As main clinical tools, we used Positive and Negative Syndrome Scale (PANSS) and Calgary depression scale for schizophrenia (CDSS). RESULTS Augmentation with sarcosine had no effect on IL-6 serum levels in all time points. We noted significant improvements in negative symptoms, general psychopathology, and total PANSS score in the sarcosine group. We found correlation of initial serum IL-6 with severity of positive symptoms and negative association between IL-6 levels reduction and positive symptoms reduction. CONCLUSIONS Sarcosine does not significantly affect IL-6 concentrations but IL-6 may be involved in mechanisms related to the presence of positive symptoms.
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Affiliation(s)
- Dominik Strzelecki
- Department of Affective and Psychotic Disorders, Medical University of Łódź, Łódź, Poland
| | | | - Adam Wysokiński
- Department of Old Age Psychiatry and Psychotic Disorders, Medical University of Łódź, Łódź, Poland
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24
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Hoenders HR, Bartels-Velthuis AA, Vollbehr NK, Bruggeman R, Knegtering H, de Jong JT. Natural Medicines for Psychotic Disorders: A Systematic Review. J Nerv Ment Dis 2018; 206:81-101. [PMID: 29373456 PMCID: PMC5794244 DOI: 10.1097/nmd.0000000000000782] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Patients with psychotic disorders regularly use natural medicines, although it is unclear whether these are effective and safe. The aim of this study was to provide an overview of evidence for improved outcomes by natural medicines. A systematic literature search was performed through Medline, PsycINFO, CINAHL, and Cochrane until May 2015. In 110 randomized controlled trials, evidence was found for glycine, sarcosine, N-acetylcysteine, some Chinese and ayurvedic herbs, ginkgo biloba, estradiol, and vitamin B6 to improve psychotic symptoms when added to antipsychotics. Ginkgo biloba and vitamin B6 seemed to reduce tardive dyskinesia and akathisia. Results on other compounds were negative or inconclusive. All natural agents, except reserpine, were well tolerated. Most study samples were small, study periods were generally short, and most results need replication. However, there is some evidence for beneficial effects of certain natural medicines.
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Affiliation(s)
- H.J. Rogier Hoenders
- *Lentis, Center for Integrative Psychiatry; †University of Groningen, University Medical Center Groningen, University Center for Psychiatry, Rob Giel Research Center; ‡Lentis Mental Health Institution; §University of Groningen, University Medical Center Groningen, Neuroimaging Center; ∥University of Amsterdam, Amsterdam, the Netherlands; and ¶Boston School of Medicine, Boston, Massachusetts
| | - Agna A. Bartels-Velthuis
- *Lentis, Center for Integrative Psychiatry; †University of Groningen, University Medical Center Groningen, University Center for Psychiatry, Rob Giel Research Center; ‡Lentis Mental Health Institution; §University of Groningen, University Medical Center Groningen, Neuroimaging Center; ∥University of Amsterdam, Amsterdam, the Netherlands; and ¶Boston School of Medicine, Boston, Massachusetts
| | - Nina K. Vollbehr
- *Lentis, Center for Integrative Psychiatry; †University of Groningen, University Medical Center Groningen, University Center for Psychiatry, Rob Giel Research Center; ‡Lentis Mental Health Institution; §University of Groningen, University Medical Center Groningen, Neuroimaging Center; ∥University of Amsterdam, Amsterdam, the Netherlands; and ¶Boston School of Medicine, Boston, Massachusetts
| | - Richard Bruggeman
- *Lentis, Center for Integrative Psychiatry; †University of Groningen, University Medical Center Groningen, University Center for Psychiatry, Rob Giel Research Center; ‡Lentis Mental Health Institution; §University of Groningen, University Medical Center Groningen, Neuroimaging Center; ∥University of Amsterdam, Amsterdam, the Netherlands; and ¶Boston School of Medicine, Boston, Massachusetts
| | - Henderikus Knegtering
- *Lentis, Center for Integrative Psychiatry; †University of Groningen, University Medical Center Groningen, University Center for Psychiatry, Rob Giel Research Center; ‡Lentis Mental Health Institution; §University of Groningen, University Medical Center Groningen, Neuroimaging Center; ∥University of Amsterdam, Amsterdam, the Netherlands; and ¶Boston School of Medicine, Boston, Massachusetts
| | - Joop T.V.M. de Jong
- *Lentis, Center for Integrative Psychiatry; †University of Groningen, University Medical Center Groningen, University Center for Psychiatry, Rob Giel Research Center; ‡Lentis Mental Health Institution; §University of Groningen, University Medical Center Groningen, Neuroimaging Center; ∥University of Amsterdam, Amsterdam, the Netherlands; and ¶Boston School of Medicine, Boston, Massachusetts
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Barber S, Olotu U, Corsi M, Cipriani A. Clozapine combined with different antipsychotic drugs for treatment-resistant schizophrenia. Cochrane Database Syst Rev 2017; 3:CD006324. [PMID: 28333365 PMCID: PMC6464566 DOI: 10.1002/14651858.cd006324.pub3] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Between 40% and 70% of people with treatment-resistant schizophrenia do not respond to clozapine, despite adequate blood levels. For these people, a number of treatment strategies have emerged, including the prescription of a second anti-psychotic drug in combination with clozapine. OBJECTIVES To determine the clinical effects of various clozapine combination strategies with antipsychotic drugs in people with treatment-resistant schizophrenia both in terms of efficacy and tolerability. SEARCH METHODS We searched the Cochrane Schizophrenia Group's Study-Based Register of Trials (to 28 August 2015) and MEDLINE (November 2008). We checked the reference lists of all identified randomised controlled trials (RCT). For the first version of the review, we also contacted pharmaceutical companies to identify further trials. SELECTION CRITERIA We included only RCTs recruiting people of both sexes, aged 18 years or more, with a diagnosis of treatment-resistant schizophrenia (or related disorders) and comparing clozapine plus another antipsychotic drug with clozapine plus a different antipsychotic drug. DATA COLLECTION AND ANALYSIS We extracted data independently. For dichotomous data, we calculated risk ratios (RRs) and 95% confidence intervals (CI) on an intention-to-treat basis using a random-effects meta-analysis. For continuous data, we calculated mean differences (MD) and 95% CIs. We used GRADE to create 'Summary of findings' tables and assessed risk of bias for included studies. MAIN RESULTS We identified two further studies with 169 participants that met our inclusion criteria. This review now includes five studies with 309 participants. The quality of evidence was low, and, due to the high degree of heterogeneity between studies, we were unable to undertake a formal meta-analysis to increase the statistical power.For this update, we specified seven main outcomes of interest: clinical response in mental state (clinically significant response, mean score/change in mental state), clinical response in global state (mean score/change in global state), weight gain, leaving the study early (acceptability of treatment), service utilisation outcomes (hospital days or admissions to hospital) and quality of life.We found some significant differences between clozapine combination strategies for global and mental state (clinically significant response and change), and there were data for leaving the study early and weight gain. We found no data for service utilisation and quality of life. Clozapine plus aripiprazole versus clozapine plus haloperidolThere was no long-term significant difference between aripiprazole and haloperidol combination strategies in change of mental state (1 RCT, n = 105, MD 0.90, 95% CI -4.38 to 6.18, low quality evidence). There were no adverse effect data for weight gain but there was a benefit of aripiprazole for adverse effects measured by the LUNSERS at 12 weeks (1 RCT, n = 105, MD -4.90, 95% CI -8.48 to -1.32) and 24 weeks (1 RCT, n = 105, MD -4.90, 95% CI -8.25 to -1.55), but not 52 weeks (1 RCT, n = 105, MD -4.80, 95% CI -9.79 to 0.19). Similar numbers of participants from each group left the study early (1 RCT, n = 106, RR 1.27, 95% CI 0.72 to 2.22, very low quality evidence). Clozapine plus amisulpride versus clozapine plus quetiapine One study showed a significant benefit of amisulpride over quetiapine in the short term, for both change in global state (Clinical Global Impression (CGI): 1 RCT, n = 50, MD -0.90, 95% CI -1.38 to -0.42, very low quality evidence) and mental state (Brief Psychiatric Rating Scale (BPRS): 1 RCT, n = 50, MD -4.00, 95% CI -5.86 to -2.14, low quality evidence). Similar numbers of participants from each group left the study early (1 RCT, n = 56, RR 0.20, 95% CI 0.02 to 1.60, very low quality evidence) Clozapine plus risperidone versus clozapine plus sulpirideThere was no difference between risperidone and sulpiride for clinically significant response, defined by the study as 20% to 50% reduction in Positive and Negative Syndrome Scale (PANSS) (1 RCT, n = 60, RR 0.82, 95% CI 0.40 to 1.68, very low quality evidence). There were similar equivocal results for weight gain (1 RCT, n = 60, RR 0.40, 95% CI 0.08 to 1.90, very low quality evidence) and mental state (PANSS total: 1 RCT, n = 60, MD -2.28, 95% CI -7.41 to 2.85, very low quality evidence). No-one left the study early. Clozapine plus risperidone versus clozapine plus ziprasidoneThere was no difference between risperidone and ziprasidone for clinically significant response (1 RCT, n = 24, RR 0.80, 95% CI 0.28 to 2.27, very low quality evidence), change in global state CGI-II score (1 RCT, n = 22, MD -0.30, 95% CI -0.82 to 0.22, very low quality evidence), change in PANSS total score (1 RCT, n = 16, MD 1.00, 95% CI -7.91 to 9.91, very low quality evidence) or leaving the study early (1 RCT, n = 24, RR 1.60, 95% CI 0.73 to 3.49, very low quality evidence). Clozapine plus ziprasidone versus clozapine plus quetiapineOne study found, in the medium term, a superior effect for ziprasidone combination compared with quetiapine combination for clinically significant response in mental state (> 50% reduction PANSS: 1 RCT, n = 63, RR 0.54, 95% CI 0.35 to 0.81, low quality evidence), global state (CGI - Severity score: 1 RCT, n = 60, MD -0.70, 95% CI -1.18 to -0.22, low quality evidence) and mental state (PANSS total score: 1 RCT, n = 60, MD -12.30, 95% CI -22.43 to -2.17, low quality evidence). There was no effect for leaving the study early (1 RCT, n = 63, RR 0.52, CI 0.05 to 5.41, very low quality evidence). AUTHORS' CONCLUSIONS The reliability of results from this review is limited, evidence is of low or very low quality. Furthermore, due to the limited number of included studies, we were unable to undertake formal meta-analyses. As a consequence, any conclusions drawn from these findings are based on single, small-sized RCTs with high risk of type II error. Properly conducted and adequately powered RCTs are required. Future trialists should seek to measure patient-important outcomes such as quality of life, as well as clinical response and adverse effects.
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Affiliation(s)
- Sarah Barber
- University of OxfordDepartment of PsychiatryWarneford HospitalOxfordUK
| | | | - Martina Corsi
- University of OxfordDepartment of PsychiatryWarneford HospitalOxfordUK
| | - Andrea Cipriani
- University of OxfordDepartment of PsychiatryWarneford HospitalOxfordUK
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Taylor DL, Tiwari AK, Lieberman JA, Potkin SG, Meltzer HY, Knight J, Remington G, Müller DJ, Kennedy JL. Pharmacogenetic Analysis of Functional Glutamate System Gene Variants and Clinical Response to Clozapine. MOLECULAR NEUROPSYCHIATRY 2016; 2:185-197. [PMID: 28277565 DOI: 10.1159/000449224] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 08/17/2016] [Indexed: 01/16/2023]
Abstract
Altered glutamate neurotransmission is implicated in the etiology of schizophrenia (SCZ) and the pharmacogenetics of response to clozapine (CLZ), which is the drug of choice for treatment-resistant SCZ. Response to antipsychotic therapy is highly variable, although twin studies suggest a genetic component. We investigated the association of 10 glutamate system gene variants with CLZ response using standard genotyping procedures. GRM2 (rs4067 and rs2518461), SLC1A2 (rs4354668, rs4534557, and rs2901534), SLC6A9 (rs12037805, rs1978195, and rs16831558), GRIA1 (rs2195450), and GAD1 (rs3749034) were typed in 163 European SCZ/schizoaffective disorder patients deemed resistant or intolerant to previous pharmacotherapy. Response was assessed following 6 months of CLZ monotherapy using change in Brief Psychiatric Rating Scale (BPRS) scores. Categorical and continuous response variables were analyzed using χ2 tests and analysis of covariance, respectively. We report no significant associations following correction for multiple testing. Prior to correction, nominally significant associations were observed for SLC6A9, SLC1A2, GRM2, and GRIA1. Most notably, CC homozygotes of rs16831558 located in the glycine transporter 1 gene (SLC6A9) exhibited an allele dose-dependent improvement in positive symptoms compared to T allele carriers (puncorrected = 0.008, pcorrected = 0.08). To clarify the role of SLC6A9 in clinical response to antipsychotic medication, and CLZ in particular, this finding warrants further investigation in larger well-characterized samples.
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Affiliation(s)
- Danielle L Taylor
- Neuroscience Research Department, Campbell Family Research Institute, Toronto, Ont., Canada; Institute of Medical Science, Toronto, Ont., Canada
| | - Arun K Tiwari
- Neuroscience Research Department, Campbell Family Research Institute, Toronto, Ont., Canada
| | - Jeffrey A Lieberman
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University and the New York State Psychiatric Institute, New York, N.Y, USA
| | - Steven G Potkin
- Department of Psychiatry, University of California, Irvine, Calif, USA
| | - Herbert Y Meltzer
- Northwestern University Feinberg School of Medicine, Chicago, Ill., USA
| | - Joanne Knight
- Neuroscience Research Department, Campbell Family Research Institute, Toronto, Ont., Canada; Institute of Medical Science, Toronto, Ont., Canada; Department of Psychiatry, University of Toronto, Toronto, Ont., Canada; Lancaster Medical School and Data Science Institute, Lancaster University, Lancaster, UK
| | - Gary Remington
- Schizophrenia Program, Centre for Addiction and Mental Health, Toronto, Ont., Canada; Department of Psychiatry, University of Toronto, Toronto, Ont., Canada
| | - Daniel J Müller
- Neuroscience Research Department, Campbell Family Research Institute, Toronto, Ont., Canada; Institute of Medical Science, Toronto, Ont., Canada; Department of Psychiatry, University of Toronto, Toronto, Ont., Canada
| | - James L Kennedy
- Neuroscience Research Department, Campbell Family Research Institute, Toronto, Ont., Canada; Institute of Medical Science, Toronto, Ont., Canada; Department of Psychiatry, University of Toronto, Toronto, Ont., Canada
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Strzelecki D, Kałużyńska O, Wysokiński A. BDNF serum levels in schizophrenic patients during treatment augmentation with sarcosine (results of the PULSAR study). Psychiatry Res 2016; 242:54-60. [PMID: 27262086 DOI: 10.1016/j.psychres.2016.05.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Revised: 04/16/2016] [Accepted: 05/15/2016] [Indexed: 12/21/2022]
Abstract
AIM Finding a relationship between schizophrenia symptoms severity and initial level of BDNF and its changes during augmentation of antipsychotic treatment with sarcosine. METHOD 57 individuals with schizophrenia with predominantly negative symptoms completed a 6-month RCT prospective study. The patients received 2g of sarcosine (n=27) or placebo (n=30) daily. At the beginning, after 6 weeks and 6 months BDNF levels were measured. Severity of symptoms was assessed using the Positive and Negative Syndrome Scale (PANSS) and Calgary Depression Scale for Schizophrenia (CDSS). RESULTS BDNF serum levels were stable after 6 weeks and 6 months in both groups. We noted improvement in negative symptoms, general psychopathology and total PANSS score in sarcosine group comparing to placebo, however there was no correlations between serum BDNF concentrations and PANSS scores in all assessments. Initial serum BDNF concentrations cannot be used as a predictor of the improvement resulting from adding sarcosine. CONCLUSIONS Our results indicate that either BDNF is not involved in the NMDA-dependent mechanism of sarcosine action or global changes in BDNF concentrations induced by amino-acid cannot be detected in blood assessments.
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Affiliation(s)
- Dominik Strzelecki
- Department of Affective and Psychotic Disorders, Medical University of Łódź, Łódź, Poland.
| | - Olga Kałużyńska
- Department of Affective and Psychotic Disorders, Medical University of Łódź, Łódź, Poland
| | - Adam Wysokiński
- Department of Old Age Psychiatry and Psychotic Disorders, Medical University of Łódź, Łódź, Poland
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Strzelecki D, Kałużyńska O, Szyburska J, Wysokiński A. MMP-9 Serum Levels in Schizophrenic Patients during Treatment Augmentation with Sarcosine (Results of the PULSAR Study). Int J Mol Sci 2016; 17:E1075. [PMID: 27409603 PMCID: PMC4964451 DOI: 10.3390/ijms17071075] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 06/08/2016] [Accepted: 06/24/2016] [Indexed: 12/18/2022] Open
Abstract
AIM Find changes in matrix metallopeptidase-9 (MMP-9) levels during augmentation of antipsychotic treatment with sarcosine and a relationship between schizophrenia symptoms severity and initial level of MMP-9. METHOD Fifty-eight patients with diagnosis of schizophrenia with predominant negative symptoms participated in a six-month prospective RCT (randomized controlled trial). The patients received two grams of sarcosine (n = 28) or placebo (n = 30) daily. At the beginning, after six weeks and after six months MMP-9 levels were measured. Severity of symptomatology was assessed with the Positive and Negative Syndrome Scale (PANSS) and Calgary Depression Scale for Schizophrenia (CDSS). RESULTS MMP-9 serum levels were stable after six weeks and six months in both groups. We noted improvement in negative symptoms, general psychopathology and total PANSS score in sarcosine group compared to placebo; however, there was no correlations between serum MMP-9 concentrations and PANSS scores in all assessments. Initial serum MMP-9 concentrations cannot be used as an improvement predictor acquired during sarcosine augmentation. CONCLUSIONS Our results indicate that either MMP-9 is not involved in the N-methyl-d-aspartate (NMDA)-dependent mechanism of sarcosine action in terms of clinical parameters or sarcosine induced changes in peripheral MMP-9 concentrations cannot be detected in blood assessments.
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Affiliation(s)
- Dominik Strzelecki
- Department of Affective and Psychotic Disorders, Medical University of Łódź, Central Clinical Hospital, Czechosłowacka 8/10, 92-216 Łódź, Poland.
| | - Olga Kałużyńska
- Department of Affective and Psychotic Disorders, Medical University of Łódź, Central Clinical Hospital, Czechosłowacka 8/10, 92-216 Łódź, Poland.
| | - Justyna Szyburska
- Department of Affective and Psychotic Disorders, Medical University of Łódź, Central Clinical Hospital, Czechosłowacka 8/10, 92-216 Łódź, Poland.
| | - Adam Wysokiński
- Department of Old Age Psychiatry and Psychotic Disorders, Medical University of Łódź, Central Clinical Hospital, Czechosłowacka 8/10, 92-216 Łódź, Poland.
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LeBlanc MA, Bettle A, Berman JN, Price VE, Pambrun C, Yu Z, Tiller M, McMaster CR, Fernandez CV. Study of Glycine and Folic Acid Supplementation to Ameliorate Transfusion Dependence in Congenital SLC25A38 Mutated Sideroblastic Anemia. Pediatr Blood Cancer 2016; 63:1307-9. [PMID: 27038157 DOI: 10.1002/pbc.25981] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 02/29/2016] [Indexed: 11/07/2022]
Abstract
Congenital sideroblastic anemia (CSA) is a hematological disorder characterized by the presence of ringed sideroblasts in bone marrow erythroid precursors. Mutations in the erythroid-specific glycine mitochondrial transporter gene SLC25A38 have been found in a subset of patients with transfusion-dependent congenital CSA. Further studies in a zebrafish model identified a promising ameliorative strategy with combined supplementation with glycine and folate. We tested this combination in three individuals with SLC25A38 CSA, with a primary objective to decrease red blood cell transfusion requirements. No significant impact was observed on transfusion requirements or any hematologic parameters.
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Affiliation(s)
| | - Amanda Bettle
- School of Nursing, IWK Health Centre, Halifax, Canada
| | - Jason N Berman
- Divison of Pediatric Hematology/Oncology, IWK Health Centre, Halifax, Canada
| | - Victoria E Price
- Divison of Pediatric Hematology/Oncology, IWK Health Centre, Halifax, Canada
| | - Chantale Pambrun
- Department of Hematopathology, IWK Health Centre, Halifax, Canada
| | - Zhijie Yu
- Department of Pediatrics, Dalhousie University, Halifax, Canada
| | - Marilyn Tiller
- Department of Pharmacy, IWK Health Centre, Halifax, Canada
| | | | - Conrad V Fernandez
- Divison of Pediatric Hematology/Oncology, IWK Health Centre, Halifax, Canada
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Strzelecki D, Kałużyńska O, Szyburska J, Wlazło A, Wysokiński A. No changes of cardiometabolic and body composition parameters after 6-month add-on treatment with sarcosine in patients with schizophrenia. Psychiatry Res 2015; 230:200-4. [PMID: 26343833 DOI: 10.1016/j.psychres.2015.08.040] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Revised: 07/29/2015] [Accepted: 08/31/2015] [Indexed: 11/28/2022]
Abstract
This study was undertaken with the purpose to determine if there are changes in metabolic parameters during 6-month add-on treatment with sarcosine in patients with schizophrenia. This was a randomized double blind, placebo-controlled and parallel group study. Eligible participants were randomly assigned to receive 2g of sarcosine (n=30) or placebo (n=29). Sarcosine was administered as supplementation to the ongoing antipsychotic treatment. Augmentation with sarcosine had no effect on any of the analyzed cardiometabolic parameters. Also, augmentation with sarcosine had no effect on any of the analyzed body composition parameters. This is the first randomized placebo-controlled study to examine the metabolic safety of sarcosine in patients with schizophrenia. Clinically, this observation is of high importance considering how prevalent are metabolic abnormalities in patients with schizophrenia.
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Affiliation(s)
- Dominik Strzelecki
- Department of Affective and Psychotic Disorders, Medical University of Lodz, Lodz, Poland
| | - Olga Kałużyńska
- Department of Affective and Psychotic Disorders, Medical University of Lodz, Lodz, Poland
| | - Justyna Szyburska
- Department of Affective and Psychotic Disorders, Medical University of Lodz, Lodz, Poland
| | - Agata Wlazło
- Department of Old Age Psychiatry and Psychotic Disorders, Medical University of Lodz, Lodz, Poland
| | - Adam Wysokiński
- Department of Old Age Psychiatry and Psychotic Disorders, Medical University of Lodz, Lodz, Poland.
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Muscatello MRA, Bruno A, De Fazio P, Segura-Garcia C, Pandolfo G, Zoccali R. Augmentation strategies in partial responder and/or treatment-resistant schizophrenia patients treated with clozapine. Expert Opin Pharmacother 2014; 15:2329-45. [PMID: 25284216 DOI: 10.1517/14656566.2014.956082] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Although clozapine (CLZ) is considered the best evidence-based therapeutic option for treatment of resistant schizophrenia patients, a significant proportion of CLZ-treated patients show a partial or inadequate response to treatment, leading to increased healthcare cost and poor quality of life for affected individuals. AREAS COVERED This paper comprises a review of main research in CLZ augmentation strategies for treatment-refractory schizophrenia, with a focus on research conducted between 1990 and 2014. Databases that were searched include: PubMed, CINAHL, EMBASE PsychINFO, AgeLine and Cochrane Database of Systematic Reviews. Primary search terms were 'clozapine augmentation', 'clozapine and add-on' and 'treatment-resistant schizophrenia', with cross reference to specific agents covered in this article. We reviewed the available evidence on CLZ augmentation with antipsychotics, antidepressants, mood stabilizers and other agents. EXPERT OPINION Many drugs have been evaluated as CLZ add-on therapies without demonstrating convincing efficacy in treating refractory schizophrenia symptoms. More research is needed to better define outcomes in schizophrenia, the topic of treatment-resistance and more well-designed trials are required to establish true efficacy and safety of CLZ augmentation strategies.
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Affiliation(s)
- Maria Rosaria A Muscatello
- University of Messina, Department of Neurosciences , Policlinico Universitario Via Consolare Valeria - Messina 98125 , Italy +39 090 22212092 ; +39 090 695136 ;
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Arango C, Garibaldi G, Marder SR. Pharmacological approaches to treating negative symptoms: a review of clinical trials. Schizophr Res 2013; 150:346-52. [PMID: 23938176 DOI: 10.1016/j.schres.2013.07.026] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Revised: 07/09/2013] [Accepted: 07/11/2013] [Indexed: 01/11/2023]
Abstract
Clinical trials of pharmacological agents targeting negative symptoms in schizophrenia are reviewed. The focus is on trials that occurred in patients who were stable on an antipsychotic medication at entry to the trial. A small number of trials compared antipsychotics as monotherapy for negative symptoms. Although the data supporting amisulpride for negative symptoms is promising the trials have limitations and it is plausible that the advantages of amisulpride over placebo may result from effects on secondary negative symptoms. Among available agents, antidepressant medications may have effects in negative symptoms. Other promising agents include minocycline, glutamatergic agents, and alpha-7 nicotinic agents. More than 15 active trials are currently underway to evaluate new treatments for negative symptoms.
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Affiliation(s)
- Celso Arango
- Child and Adolescent Psychiatry Department, Hospital General Universitario Gregorio Marañón, IiSGM, School of Medicine, Universidad Complutense, CIBERSAM, Madrid, Spain
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McCullumsmith RE, Hammond J, Funk A, Meador-Woodruff JH. Recent advances in targeting the ionotropic glutamate receptors in treating schizophrenia. Curr Pharm Biotechnol 2012; 13:1535-42. [PMID: 22283761 DOI: 10.2174/138920112800784899] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 05/08/2011] [Accepted: 05/24/2011] [Indexed: 12/28/2022]
Abstract
The treatment of schizophrenia has been focused on modulation of dopamine receptors for over 50 years. Recent developments have implicated other neurotransmitter systems in the pathophysiology of this illness. The discovery and characterization of glutamate receptors and their roles in the brain has lead to novel approaches for the treatment of schizophrenia. In this article, we review drugs that modulate ionotropic gluamate receptors and discuss their efficacy for the treatment of this often debilitating severe mental illness.
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Affiliation(s)
- Robert E McCullumsmith
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham, AL 35294, USA
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Sommer IE, Begemann MJH, Temmerman A, Leucht S. Pharmacological augmentation strategies for schizophrenia patients with insufficient response to clozapine: a quantitative literature review. Schizophr Bull 2012; 38:1003-11. [PMID: 21422107 PMCID: PMC3446238 DOI: 10.1093/schbul/sbr004] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND When schizophrenia patients have insufficient response to clozapine, pharmacological augmentation is often applied. This meta-analysis summarizes available evidence on efficacy of pharmacological augmentation of clozapine treatment in schizophrenia spectrum disorder. METHODS Only double-blind randomized controlled studies were included. Primary outcome measure was total symptom severity, and secondary outcome measures were subscores for positive and negative symptoms. Effect sizes were calculated from individual studies and combined to standardized mean differences (Hedges's g). RESULTS Twenty-nine studies reporting on 15 different augmentations were included. Significant better efficacy than placebo on total symptom severity was observed for lamotrigine, citalopram, sulpiride, and CX516 (a glutamatergic agonist). The positive effect of lamotrigine disappeared after outlier removal. The other positive findings were based on single studies. Significantly better efficacy on positive symptom severity was observed for topiramate and sulpiride. The effect of topiramate disappeared after outlier removal. Results for sulpiride were based on a single randomized controlled trial. Citalopram, sulpiride, and CX516 showed better efficacy for negative symptoms than placebo, all based on single studies. CONCLUSIONS Evidence for efficacy of clozapine augmentation is currently scarce. Efficacy of lamotrigine and topiramate were both dependent on single studies with deviating findings. The effect of citalopram, sulpiride, and CX516 were based on single studies. Thus, despite their popularity, pharmacological augmentations of clozapine are not (yet) demonstrated to be superior to placebo.
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Affiliation(s)
- Iris E. Sommer
- Neuroscience Department of the University Medical Center Utrecht & Rudolf Magnus Institute for Neuroscience, Utrecht, the Netherlands,To whom correspondence should be addressed; tel: +31-88-7556370, fax: +31-88-7555443, e-mail:
| | - Marieke J. H. Begemann
- Neuroscience Department of the University Medical Center Utrecht & Rudolf Magnus Institute for Neuroscience, Utrecht, the Netherlands
| | - Anke Temmerman
- Neuroscience Department of the University Medical Center Utrecht & Rudolf Magnus Institute for Neuroscience, Utrecht, the Netherlands
| | - Stefan Leucht
- Department of Psychiatry and Psychotherapy, Technische Universität München, München, Germany
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Hons J, Vasatova M, Cermakova E, Doubek P, Libiger J. Different serine and glycine metabolism in patients with schizophrenia receiving clozapine. J Psychiatr Res 2012; 46:811-8. [PMID: 22502820 DOI: 10.1016/j.jpsychires.2012.03.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 02/07/2012] [Accepted: 03/12/2012] [Indexed: 10/28/2022]
Abstract
Dysfunction of the N-methyl-d-aspartate receptor, which is modulated by excitatory amino acids (EAA), is involved in the pathophysiology of schizophrenia. The effects of antipsychotics on EAA metabolism are uncertain. Positive clinical effects of treatment with antipsychotics were not always associated with changes in EAA serum levels in patients with schizophrenia in clinical trials. To examine EAA serum levels in relation to the intensity of psychotic symptoms and the type of medication received we compared these variables among patients with schizophrenia (n = 49) treated with first (FGA) or second (SGA) generation antipsychotics or clozapine. Glutamate, aspartate, glycine, total serine and d-serine serum levels were measured by High Performance Liquid Chromatography. The Positive and Negative Syndrome Scale (PANSS) and the Scale for the Assessment of Negative Symptoms (SANS) were used to assess symptoms of schizophrenia. Lower average levels of glycine and total serine were found in the serum of patients receiving clozapine when compared to the groups of patients treated with FGA or SGA. There were no differences in serum glutamate, aspartate or d-serine levels or in the intensity of schizophrenic symptoms assessed by PANSS or SANS among the groups of patients treated with FGA or SGA or clozapine. Lower glycine and total serine serum levels could be caused by the particular characteristics of the population of patients receiving clozapine rather than as an effect of the clozapine. The results suggest selective deficiency of l-serine synthesis in the patients with resistance to non-clozapine treatment. It might be an unique biochemical and pathophysiological characteristic of the treatment-resistance in schizophrenia.
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Affiliation(s)
- Jaromir Hons
- Department of Psychiatry, Regional Hospital Liberec, Husova 10, 460 63 Liberec, Czech Republic.
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Targeting glutamate system for novel antipsychotic approaches: Relevance for residual psychotic symptoms and treatment resistant schizophrenia. Eur J Pharmacol 2012; 682:1-11. [DOI: 10.1016/j.ejphar.2012.02.033] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Revised: 02/08/2012] [Accepted: 02/15/2012] [Indexed: 01/04/2023]
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Differential effects of AMPA receptor potentiators and glycine reuptake inhibitors on antipsychotic efficacy and prefrontal glutamatergic transmission. Psychopharmacology (Berl) 2012; 221:115-31. [PMID: 22068461 DOI: 10.1007/s00213-011-2554-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Accepted: 10/17/2011] [Indexed: 12/30/2022]
Abstract
RATIONALE The α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor positive allosteric modulators (AMPA-PAMs), Org 24448 and Org 26576, and the glycine transporter-1 (GlyT-1) inhibitor Org 25935 are developed for treatment of schizophrenia. OBJECTIVES Here we examined experimentally the ability of co-administration of these AMPA-PAMs or the GlyT-1 inhibitor to augment the antipsychotic activity and effect on cortical N-methyl-D: -aspartate (NMDA) receptor-mediated transmission of risperidone, olanzapine, or haloperidol. METHODS We examined antipsychotic efficacy using the conditioned avoidance response (CAR) test, extrapyramidal side effect liability using a catalepsy test, and cortical NMDA receptor-mediated glutamatergic transmission using intracellular electrophysiological recording technique in vitro. RESULTS Both AMPA-PAMs enhanced the suppression of CAR induced by risperidone or olanzapine, and Org 24448 also enhanced the effect of haloperidol. In contrast, the GlyT-1 inhibitor did not cause any behaviorally significant effect in the CAR test. However, the GlyT-1 inhibitor, but not the AMPA-PAMs, produced a large facilitation of NMDA-induced currents. All three drugs potentiated the effect of risperidone but not haloperidol on these currents. The GlyT-1 inhibitor also facilitated the effect of olanzapine. All drugs potentiated the effect of risperidone on electrically stimulated excitatory postsynaptic potentials (EPSP) in cortical pyramidal cells, whereas only the GlyT inhibitor facilitated the effect of olanzapine. CONCLUSIONS Our results suggest that the AMPA-PAMs, when compared to the GlyT-1 inhibitor, show differential effects in terms of augmentation of antipsychotic efficacy, particularly when combined with risperidone or olanzapine. Both AMPA-PAMs and the GlyT-1 inhibitor may also improve negative symptoms and cognitive impairments in schizophrenia, in particular when combined with risperidone.
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Porcelli S, Balzarro B, Serretti A. Clozapine resistance: augmentation strategies. Eur Neuropsychopharmacol 2012; 22:165-82. [PMID: 21906915 DOI: 10.1016/j.euroneuro.2011.08.005] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Revised: 08/12/2011] [Accepted: 08/13/2011] [Indexed: 12/16/2022]
Abstract
BACKGROUND Clozapine (CLZ) is not effective in more than 50% of treatment-resistant schizophrenic patients. In these cases, several pharmacological strategies are used in clinical practice, with different levels of evidence for both safety and efficacy. OBJECTIVES In the present paper we critically reviewed literature data regarding the efficacy and safety of adjunctive agents in CLZ-resistant schizophrenics. The following classes of agents were considered: 1) antipsychotics, 2) antidepressants, 3) mood stabilizers, 4) other agents (e.g. fatty acid supplement and glutamatergic agents), 5) electroconvulsive therapy (ECT). For lamotrigine and risperidone sufficient data were available to perform a meta-analysis. METHODS A Medline literature search covering a 20-year period was performed. For the meta-analysis, data were entered and analyzed with the Cochrane Collaboration Review Manager Software (RevMan version 5). RESULTS 62 pertinent studies were identified, including 1556 schizophrenic or schizoaffective patients. Among treatments investigated, there is evidence for CLZ augmentation with 1) amisulpride and aripiprazole, 2) mirtazapine and 3) ethyl eicosapentaenoic acid (E-EPA). Although promising, ECT augmentation needs further validation. The meta-analyses did not support either the use of risperidone or lamotrigine as CLZ adjunct. CONCLUSION Overall, there is scarce evidence of efficacy and safety as regards adjunctive strategies for CLZ-resistant patients. However, several limitations do not allow to draw any definitive conclusion; among these we underline the small sample size of clinical trials, the variable definitions of CLZ resistance, the heterogeneity of outcome measures and methodological designs.
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Affiliation(s)
- Stefano Porcelli
- Institute of Psychiatry, University of Bologna, Viale Carlo Pepoli 5, 40123 Bologna, Italy
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Abstract
BACKGROUND Based on the glutamatergic NMDA receptor hypofunction theory of schizophrenia, NMDA receptor modulators (NMDARMs) may have therapeutic potential in the treatment of schizophrenia. OBJECTIVE This meta-analysis aimed to evaluate the potential of modulators of the NMDA receptor as adjunctive therapy for schizophrenia, using the results from published trials. DATA SOURCES A primary electronic search for controlled clinical trials using NMDARMs in schizophrenia was conducted on the PubMed, Cochrane Library, EMBASE, CINAHL® and PsycINFO databases. A secondary manual search of references from primary publications was also performed. STUDY SELECTION Inclusion criteria were the application of an established method of diagnosis, randomized case assignment, comparison of NMDARM add-on therapy with placebo, and double-blind assessment of symptoms in chronic schizophrenia using standardized rating scales. Results were based on a total sample size of 1253 cases from 29 trials that fulfilled the specified criteria. DATA EXTRACTION Scores on rating scales or on their relevant subscales were obtained for all selected studies from published results for the minimum dataset to compute the difference between post- and pre-trial scores and their pooled standard deviation for NMDARM add-on therapy and placebo groups for negative, positive and total symptoms. RESULTS A negative standardized mean difference (SMD) indicates therapeutic benefit in favour of NMDARM add-on therapy and all SMD results mentioned here are statistically significant. The overall effect size for NMDARMs as a group was small for negative (SMD -0.27) and medium for total (SMD -0.40) symptoms of chronic schizophrenia. Subgroup analysis revealed medium effect sizes for D-serine and N-acetyl-cysteine (NAC) for negative (SMD -0.53 and -0.45, respectively) and total (SMD -0.40 and -0.64, respectively) symptoms, and for glycine (SMD -0.66) and sarcosine (SMD -0.41) for total symptoms. As adjuvants to non-clozapine antipsychotics, additional therapeutic benefits were observed for NMDARM as a group (SMD -0.14) and glycine (SMD -0.54) for positive symptoms; D-serine (SMD -0.54), NAC (SMD -0.45) and sarcosine (SMD -0.39) for negative symptoms; and NMDARM as a group (SMD -0.38), D-serine (SMD -0.40), glycine (SMD -1.12), NAC (SMD -0.64) and sarcosine (SMD -0.53) for total symptoms. When added to clozapine, none of the drugs demonstrated therapeutic potential, while addition of glycine (SMD +0.56) worsened positive symptoms. CONCLUSIONS Taking into consideration the number of trials and sample size in subgroup analyses, D-serine, NAC and sarcosine as adjuncts to non-clozapine antipsychotics have therapeutic benefit in the treatment of negative and total symptoms of chronic schizophrenia. While glycine improves positive and total symptoms as an adjuvant to non-clozapine antipsychotics, it worsens them when added to clozapine.
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Affiliation(s)
- Surendra P Singh
- General Adult Psychiatry, Mental Health Directorate, Wolverhampton City Primary Care Trust, Wolverhampton, West Midlands, UK
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Citrome L. Treatment-refractory schizophrenia: what is it and what has been done about it? ACTA ACUST UNITED AC 2011. [DOI: 10.2217/npy.11.35] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Nakato K, Harada K, Tobe T, Yamaji T, Takakura S. [Stimulating glutamatergic neurons as a potential novel therapeutic avenue for schizophrenia]. Nihon Yakurigaku Zasshi 2010; 136:128-32. [PMID: 20838012 DOI: 10.1254/fpj.136.128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Chaves C, Marque CR, Trzesniak C, Machado de Sousa JP, Zuardi AW, Crippa JAS, Dursun SM, Hallak JE. Glutamate-N-methyl-D-aspartate receptor modulation and minocycline for the treatment of patients with schizophrenia: an update. Braz J Med Biol Res 2010; 42:1002-14. [PMID: 19855900 DOI: 10.1590/s0100-879x2009001100002] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2009] [Accepted: 09/15/2009] [Indexed: 01/31/2023] Open
Abstract
Growing consistent evidence indicates that hypofunction of N-methyl-D-aspartate (NMDA) transmission plays a pivotal role in the neuropathophysiology of schizophrenia. Hence, drugs which modulate NMDA neurotransmission are promising approaches to the treatment of schizophrenia. The aim of this article is to review clinical trials with novel compounds acting on the NMDA receptor (NMDA-R). This review also includes a discussion and translation of neuroscience into schizophrenia therapeutics. Although the precise mechanism of action of minocycline in the brain remains unclear, there is evidence that it blocks the neurotoxicity of NMDA antagonists and may exert a differential effect on NMDA signaling pathways. We, therefore, hypothesize that the effects of minocycline on the brain may be partially modulated by the NMDA-R or related mechanisms. Thus, we have included a review of minocycline neuroscience. The search was performed in the PubMed, Web of Science, SciELO, and Lilacs databases. The results of glycine and D-cycloserine trials were conflicting regarding effectiveness on the negative and cognitive symptoms of schizophrenia. D-serine and D-alanine showed a potential effect on negative symptoms and on cognitive deficits. Sarcosine data indicated a considerable improvement as adjunctive therapy. Finally, minocycline add-on treatment appears to be effective on a broad range of psychopathology in patients with schizophrenia. The differential modulation of NMDA-R neurosystems, in particular synaptic versus extrasynaptic NMDA-R activation and specific subtypes of NMDA-R, may be the key mediators of neurogenesis and neuroprotection. Thus, psychotropics modulating NMDA-R neurotransmission may represent future monotherapy or add-on treatment strategies in the treatment of schizophrenia.
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Affiliation(s)
- C Chaves
- Departamento de Neurociências e Ciências do Comportamento, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil
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Hons J, Zirko R, Ulrychova M, Cermakova E, Doubek P, Libiger J. Glycine serum level in schizophrenia: relation to negative symptoms. Psychiatry Res 2010; 176:103-8. [PMID: 20096465 DOI: 10.1016/j.psychres.2009.11.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2008] [Revised: 09/11/2009] [Accepted: 11/10/2009] [Indexed: 10/19/2022]
Abstract
Glycine acts as an endogenous selective co-agonist at the glycine modulatory site of the NMDA (N-methyl-d-aspartate) receptor. Significantly decreased glycine serum levels were reported in patients with schizophrenia in comparison to healthy controls. Administration of glycine improved negative symptoms in patients with schizophrenia treated with antipsychotics in some clinical trials. We hypothesized that glycine serum levels might be associated with intensity of negative symptoms in schizophrenia. Fifty outpatients with the diagnosis of schizophrenia as defined by ICD-10 and fifty age- and gender-matched healthy controls were recruited into the study. Glycine serum levels were measured by high performance liquid chromatography (HPLC). We used the Positive and Negative Syndrome Scale (PANSS) and the Scale for the Assessment of Negative Symptoms (SANS) to assess the symptoms of schizophrenia in the patients. We found mean glycine serum levels to be significantly lower in patients than in controls. This difference was only caused by findings in the male study population. Glycine serum levels were negatively associated with intensity of negative symptoms assessed by the PANSS negative subscale and the SANS total scores in the patients. These data suggest a possible implication of NMDA receptor dysfunction in the pathogenesis of negative symptoms in schizophrenia.
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Affiliation(s)
- Jaromir Hons
- Department of Psychiatry, Regional Hospital Liberec, Husova 10, 460 63 Liberec 1, Czech Republic.
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Kaufman MJ, Prescot AP, Ongur D, Evins AE, Barros TL, Medeiros CL, Covell J, Wang L, Fava M, Renshaw PF. Oral glycine administration increases brain glycine/creatine ratios in men: a proton magnetic resonance spectroscopy study. Psychiatry Res 2009; 173:143-9. [PMID: 19556112 PMCID: PMC2713375 DOI: 10.1016/j.pscychresns.2009.03.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2008] [Revised: 03/05/2009] [Accepted: 03/10/2009] [Indexed: 11/30/2022]
Abstract
Oral high-dose glycine administration has been used as an adjuvant treatment for schizophrenia to enhance glutamate neurotransmission and mitigate glutamate system hypofunction thought to contribute to the disorder. Prior studies in schizophrenia subjects documented clinical improvements after 2 weeks of oral glycine administration, suggesting that brain glycine levels are sufficiently elevated to evoke a clinical response within that time frame. However, no human study has reported on brain glycine changes induced by its administration. We utilized a noninvasive proton magnetic resonance spectroscopy ((1)H-MRS) technique termed echo time-averaged (TEAV) (1)H-MRS, which permits noninvasive quantification of brain glycine in vivo, to determine whether 2 weeks of oral glycine administration (peak dose of 0.8 g/kg/day) increased brain glycine/creatine (Gly/Cr) ratios in 11 healthy adult men. In scans obtained 17 h after the last glycine dose, brain (Gly/Cr) ratios were significantly increased. The data indicate that it is possible to measure brain glycine changes with proton spectroscopy. Developing a more comprehensive understanding of human brain glycine dynamics may lead to optimized use of glycine site agonists and glycine transporter inhibitors to treat schizophrenia, and possibly to treat other disorders associated with glutamate system dysfunction.
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Affiliation(s)
- Marc J. Kaufman
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478,Address Correspondence to: Marc J. Kaufman, Ph.D., Brain Imaging Center, McLean Hospital, 115 Mill St., Belmont, MA 02478 USA, 617-855-3469 (office), 617-855-2770 (FAX),
| | - Andrew P. Prescot
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478
| | - Dost Ongur
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478
| | | | - Tanya L. Barros
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478
| | - Carissa L. Medeiros
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478
| | - Julie Covell
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478
| | - Liqun Wang
- Translational Medicine and Genetics, GlaxoSmithKline, Greenford, United Kingdom
| | | | - Perry F. Renshaw
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478
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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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Cipriani A, Boso M, Barbui C. Clozapine combined with different antipsychotic drugs for treatment resistant schizophrenia. Cochrane Database Syst Rev 2009:CD006324. [PMID: 19588385 PMCID: PMC4164450 DOI: 10.1002/14651858.cd006324.pub2] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Although clozapine has been shown to be the treatment of choice in people with schizophrenia that are resistant to treatment, one third to two thirds of people still have persistent positive symptoms despite clozapine monotherapy of adequate dosage and duration. The need to provide effective therapeutic interventions to patients who do not have an optimal response to clozapine is the most common reason for simultaneously prescribing a second antipsychotic drug in combination with clozapine. OBJECTIVES To determine the efficacy and tolerability of various clozapine combination strategies with antipsychotics in people with treatment resistant schizophrenia. SEARCH STRATEGY We searched the Cochrane Schizophrenia Group Trials Register (March 2008) and MEDLINE (up to November 2008). We checked reference lists of all identified randomised controlled trials and requested pharmaceutical companies marketing investigational products to provide relevant published and unpublished data. SELECTION CRITERIA We included only randomised controlled trials recruiting people of both sexes, aged 18 years or more, with a diagnosis of treatment-resistant schizophrenia (or related disorders) and comparing clozapine plus another antipsychotic drug with clozapine plus a different antipsychotic drug. DATA COLLECTION AND ANALYSIS Two review authors independently extracted data and resolved disagreement by discussion with third member of the team. When insufficient data were provided, we contacted the study authors. MAIN RESULTS Three small (range of number of participants 28 to 60) randomised controlled trials were included in the review. Even though results from individual studies did not find that one combination strategy is better than the others, the methodological quality of included studies was too low to allow authors to use the collected data to answer the research question correctly. AUTHORS' CONCLUSIONS In this review we considered the risk of bias too high because of the poor quality of the retrieved information (small sample size, heterogeneity of comparisons, flaws in the design, conduct and analysis). Although clinical guidelines recommend a second antipsychotic in addition to clozapine in partially responsive patients with schizophrenia, the present systematic review was not able to show if any particular combination strategy was superior to the others. New, properly conducted, randomised controlled trials independent from the pharmaceutical industry need to recruit many more patients to give a reliable estimate of effect or of no effect of antipsychotics as combination treatment with clozapine in patients who do not have an optimal response to clozapine monotherapy.
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Affiliation(s)
- Andrea Cipriani
- Department of Medicine and Public Health, Section of Psychiatry and Clinical Psychology, University of Verona, Verona, Italy
| | - Marianna Boso
- Department of Applied Health and Behavioral Sciences, Section of Psychiatry, University of Pavia, Pavia, Italy
| | - Corrado Barbui
- Department of Medicine and Public Health, Section of Psychiatry and Clinical Psychology, University of Verona, Verona, Italy
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Masoudzadeh A, Khalilian AR. Comparative study of clozapine, electroshock and the combination of ECT with clozapine in treatment-resistant schizophrenic patients. Pak J Biol Sci 2009; 10:4287-90. [PMID: 19086588 DOI: 10.3923/pjbs.2007.4287.4290] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The aim of this study was to compare the results of treatment with clozapine alone, Electroshock (ECT) alone and the combination of clozapine with ECT in treatment-resistant schizophrenic patients. Eighteen treatment-resistant schizophrenic patients were assigned to three equal groups: one group was given clozapine; one group was treated with ECT and one group was treated with the combination of clozapine and ECT. The treatment response was evaluated using the PANSS criteria and the data were analyzed with ANOVA. Combination therapy was superior to single modality therapy. The reduction of PANSS scores was 46% in the clozapine group, 40% in the ECT groups and 71% in the combination group, the difference between the combination group and the other groups was statistically significant (p < 0.05). Patients had a quick response to combination treatment, which resulted in a higher cure rate of positive and negative symptoms and improved the patients general performance. There were no significant adverse effects with combination treatment. Combination treatment with clozapine and ECT was safe and effective in treatment-resistant schizophrenic patients. It should be considered for the treatment of treatment-resistant schizophrenic patients.
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Affiliation(s)
- A Masoudzadeh
- Department of Psychiatry, Research Center of Psychiatric and Behavior Science, Sari, Iran
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Shim SS, Hammonds MD, Kee BS. Potentiation of the NMDA receptor in the treatment of schizophrenia: focused on the glycine site. Eur Arch Psychiatry Clin Neurosci 2008; 258:16-27. [PMID: 17901997 DOI: 10.1007/s00406-007-0757-8] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2007] [Accepted: 07/27/2007] [Indexed: 12/31/2022]
Abstract
N-methyl-D-aspartate receptor (NMDAR) hypo-function theory of schizophrenia proposes that impairment in NMDAR function be associated with the pathophysiology of schizophrenia and suggests that enhancement of the receptor function may produce efficacy for schizophrenia. Consistent with this theory, for the last decade, clinical trials have demonstrated that the enhancement of NMDAR function by potentiating the glycine site of the receptor is efficacious in the treatment of schizophrenia. Full agonists of the glycine site, glycine and D-serine and a glycine transporter-1 inhibitor, sarcosine, added to antipsychotic drugs, have been shown to be effective in the treatment of negative symptoms and possibly cognitive symptoms without significantly affecting the positive symptoms of schizophrenia. A partial agonist of the glycine site, D-cycloserine, added to antipsychotic drugs, can be effective for the negative symptoms at the therapeutic doses. However, these drugs have not shown clinical efficacy when added to clozapine, suggesting that the interactions of clozapine and the glycine site potentiators may be different from those of other antipsychotic drugs and the potentiators. This article suggests that the glycine site potentiators may produce efficacy for negative and cognitive symptoms by blocking apoptosis-like neuropathological processes in patients with chronic schizophrenia and thereby can deter progressive deterioration of the disorder. This article proposes a polypharmacy of glycine site potentiators augmented with antipsychotic drugs to control positive and negative symptoms in a synergistic manner and block deterioration in schizophrenia. Since the NMDAR complex consists of multiple sites modulating receptor functions, the efficacy of glycine site potentiators for schizophrenia suggests the possibility that manipulation of other modulating sites of the NMDAR can also be efficacious in the treatment of schizophrenia.
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Affiliation(s)
- Seong S Shim
- Case Western Reserve University School of Medicine, Department of Psychiatry, Cleveland VA Medical Center Psychiatric Services 116 A(W), Cleveland, Ohio 44106, USA.
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Acute high-dose glycine attenuates mismatch negativity (MMN) in healthy human controls. Psychopharmacology (Berl) 2008; 196:451-60. [PMID: 17952411 DOI: 10.1007/s00213-007-0976-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2007] [Accepted: 10/03/2007] [Indexed: 10/22/2022]
Abstract
RATIONALE Schizophrenia is commonly associated with impairments in pre-attentive change detection as represented by reduced mismatch negativity (MMN). The neurochemical basis of MMN has been linked to N-methyl-D: -aspartate (NMDA) receptor function. Glycine augments NMDA receptor function via stimulation of the glycine modulatory site of the NMDA receptor and has been shown to effectively reduce negative symptoms in schizophrenia. However, no study has investigated the possible effects of high-dose glycine on MMN. Further, the physiological consequences of administering high-dose glycine in subjects with normal NMDA receptor function are unknown. OBJECTIVES The aim of the present project was to investigate the acute effects of a single large dose of glycine on the human MMN in healthy subjects. MATERIALS AND METHODS Sixteen healthy male subjects participated in a double blind, placebo-controlled, crossover design in which each subject was tested under two acute treatment conditions separated by a 1-week washout period; placebo and 0.8 g/kg glycine. The subjects were exposed to a duration-MMN paradigm with 50-ms standard tones (91%) and 100-ms deviant tones (9%). RESULTS The results showed that glycine significantly attenuated duration MMN amplitude at frontal electrodes. There was no effect of glycine on MMN latencies or on amplitudes or latencies of N1, N2 and P3a. CONCLUSIONS These findings suggest that an acute high dosage of glycine attenuates MMN in healthy controls, raising the possibility that optimal effects of glycine and other glycine agonists may depend on the integrity of the NMDA receptor system.
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Goff DC, Lamberti JS, Leon AC, Green MF, Miller AL, Patel J, Manschreck T, Freudenreich O, Johnson SA. A placebo-controlled add-on trial of the Ampakine, CX516, for cognitive deficits in schizophrenia. Neuropsychopharmacology 2008; 33:465-72. [PMID: 17487227 PMCID: PMC3098468 DOI: 10.1038/sj.npp.1301444] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
AMPA-receptor-positive modulators (Ampakines) facilitate learning and memory in animal models and in preliminary trials in human subjects. CX516 is the first Ampakine to be studied for cognitive enhancement in schizophrenia. Stable schizophrenia patients treated with clozapine (n=52), olanzapine (n=40), or risperidone (n=13) were randomly assigned to add-on treatment with CX516 900 mg three times daily or placebo for 4 weeks. Subjects were assessed with a cognitive battery at baseline, week 4, and at 4-week follow-up. Clinical scales and safety monitoring were also performed. The primary endpoint was the change from baseline in a composite cognitive score at week 4 for the intent-to-treat sample. Additional analyses examined change in symptom rating scores and examined drug effects on patients treated with clozapine separately from patients treated with either olanzapine or risperidone. A total of 105 patients were randomized and 95 (90%) completed the 4-week trial. Patients treated with CX516 did not differ from placebo in change from baseline on the composite cognitive score, or on any cognitive test at weeks 4 or 8. The between groups effect size at week 4 for the cognitive composite score was -0.19 for clozapine-treated patients and 0.24 for patients treated with olanzapine or risperidone. The placebo group improved more on the PANSS total score than the CX516 group; no other clinical rating differed between treatment groups. CX516 was associated with fatigue, insomnia and epigastric discomfort compared to placebo, but was generally well tolerated. CX516 was not effective for cognition or for symptoms of schizophrenia when added to clozapine, olanzapine, or risperidone.
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Affiliation(s)
- Donald C Goff
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
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