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Haszto CS, Stanley JA, Iyengar S, Prasad KM. Regionally Distinct Alterations in Membrane Phospholipid Metabolism in Schizophrenia: A Meta-analysis of Phosphorus Magnetic Resonance Spectroscopy Studies. BIOLOGICAL PSYCHIATRY: COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2019; 5:264-280. [PMID: 31748123 DOI: 10.1016/j.bpsc.2019.09.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 09/12/2019] [Accepted: 09/13/2019] [Indexed: 12/21/2022]
Abstract
BACKGROUND Existing data on altered membrane phospholipid metabolism in schizophrenia are diverse. We conducted a meta-analysis of studies of phosphorus magnetic resonance spectroscopy, a noninvasive imaging approach that can assess molecular biochemistry of cortex by measuring phosphomonoester (PME) and phosphodiester (PDE) levels, which can provide evidence of altered biochemical processes involved in neuropil membrane expansion and contraction in schizophrenia. METHODS We analyzed PME and PDE data in the frontal and temporal lobes in subjects with schizophrenia from 24 peer-reviewed publications using the MAVIS package in R by building random- and fixed-effects models. Heterogeneity of effect sizes, effects of publication bias, and file drawer analysis were also assessed. RESULTS Subjects with schizophrenia showed lower PME levels in the frontal regions (p = .008) and elevated PDE levels in the temporal regions (p < .001) with significant heterogeneity. We noted significant publication bias and file drawer effect for frontal PME and PDE and temporal PDE levels, but not for temporal PME levels. Fail-safe analysis estimated that a high number of negative studies were required to provide nonsignificant results. CONCLUSIONS Despite methodological differences, these phosphorus magnetic resonance spectroscopy studies demonstrate regionally specific imbalance in membrane phospholipid metabolism related to neuropil in subjects with schizophrenia compared with control subjects reflecting neuropil contraction. Specifically, decreased PME levels in the frontal regions and elevated PDE levels in the temporal regions provide evidence of decreased synthesis and increased degradation of neuropil membrane, respectively. Notwithstanding significant heterogeneity and publication bias, a large number of negative studies are required to render the results of this meta-analysis nonsignificant. These findings warrant further postmortem and animal studies.
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Affiliation(s)
- Connor S Haszto
- Kenneth Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Jeffrey A Stanley
- Department of Psychiatry and Behavioral Neuroscience, Wayne State University School of Medicine, Detroit, Michigan
| | - Satish Iyengar
- Department of Statistics, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Konasale M Prasad
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania; Veterans Affairs Pittsburgh Health System, Pittsburgh, Pennsylvania.
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Schmitt A, Martins-de-Souza D, Akbarian S, Cassoli JS, Ehrenreich H, Fischer A, Fonteh A, Gattaz WF, Gawlik M, Gerlach M, Grünblatt E, Halene T, Hasan A, Hashimoto K, Kim YK, Kirchner SK, Kornhuber J, Kraus TFJ, Malchow B, Nascimento JM, Rossner M, Schwarz M, Steiner J, Talib L, Thibaut F, Riederer P, Falkai P. Consensus paper of the WFSBP Task Force on Biological Markers: Criteria for biomarkers and endophenotypes of schizophrenia, part III: Molecular mechanisms. World J Biol Psychiatry 2017; 18:330-356. [PMID: 27782767 DOI: 10.1080/15622975.2016.1224929] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVES Despite progress in identifying molecular pathophysiological processes in schizophrenia, valid biomarkers are lacking for both the disease and treatment response. METHODS This comprehensive review summarises recent efforts to identify molecular mechanisms on the level of protein and gene expression and epigenetics, including DNA methylation, histone modifications and micro RNA expression. Furthermore, it summarises recent findings of alterations in lipid mediators and highlights inflammatory processes. The potential that this research will identify biomarkers of schizophrenia is discussed. RESULTS Recent studies have not identified clear biomarkers for schizophrenia. Although several molecular pathways have emerged as potential candidates for future research, a complete understanding of these metabolic pathways is required to reveal better treatment modalities for this disabling condition. CONCLUSIONS Large longitudinal cohort studies are essential that pair a thorough phenotypic and clinical evaluation for example with gene expression and proteome analysis in blood at multiple time points. This approach might identify biomarkers that allow patients to be stratified according to treatment response and ideally also allow treatment response to be predicted. Improved knowledge of molecular pathways and epigenetic mechanisms, including their potential association with environmental influences, will facilitate the discovery of biomarkers that could ultimately be effective tools in clinical practice.
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Affiliation(s)
- Andrea Schmitt
- a Department of Psychiatry and Psychotherapy , LMU Munich , Germany.,b Laboratory of Neuroscience (LIM27) , Institute of Psychiatry, University of Sao Paulo , Sao Paulo , Brazil
| | - Daniel Martins-de-Souza
- b Laboratory of Neuroscience (LIM27) , Institute of Psychiatry, University of Sao Paulo , Sao Paulo , Brazil.,c Laboratory of Neuroproteomics, Department of Biochemistry , Institute of Biology University of Campinas (UNICAMP), Campinas , SP , Brazil
| | - Schahram Akbarian
- d Division of Psychiatric Epigenomics, Departments of Psychiatry and Neuroscience , Mount Sinai School of Medicine , New York , USA
| | - Juliana S Cassoli
- c Laboratory of Neuroproteomics, Department of Biochemistry , Institute of Biology University of Campinas (UNICAMP), Campinas , SP , Brazil
| | - Hannelore Ehrenreich
- e Clinical Neuroscience , Max Planck Institute of Experimental Medicine, DFG Centre for Nanoscale Microscopy & Molecular Physiology of the Brain , Göttingen , Germany
| | - Andre Fischer
- f Research Group for Epigenetics in Neurodegenerative Diseases , German Centre for Neurodegenerative Diseases (DZNE), Göttingen , Germany.,g Department of Psychiatry and Psychotherapy , University Medical Centre Göttingen , Germany
| | - Alfred Fonteh
- h Neurosciences , Huntington Medical Research Institutes , Pasadena , CA , USA
| | - Wagner F Gattaz
- b Laboratory of Neuroscience (LIM27) , Institute of Psychiatry, University of Sao Paulo , Sao Paulo , Brazil
| | - Michael Gawlik
- i Department of Psychiatry and Psychotherapy , University of Würzburg , Germany
| | - Manfred Gerlach
- j Centre for Mental Health, Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy , University of Würzburg , Germany
| | - Edna Grünblatt
- i Department of Psychiatry and Psychotherapy , University of Würzburg , Germany.,k Department of Child and Adolescent Psychiatry and Psychotherapy , Psychiatric Hospital, University of Zürich , Switzerland.,l Neuroscience Centre Zurich , University of Zurich and the ETH Zurich , Switzerland.,m Zurich Centre for Integrative Human Physiology , University of Zurich , Switzerland
| | - Tobias Halene
- d Division of Psychiatric Epigenomics, Departments of Psychiatry and Neuroscience , Mount Sinai School of Medicine , New York , USA
| | - Alkomiet Hasan
- a Department of Psychiatry and Psychotherapy , LMU Munich , Germany
| | - Kenij Hashimoto
- n Division of Clinical Neuroscience , Chiba University Centre for Forensic Mental Health , Chiba , Japan
| | - Yong-Ku Kim
- o Department of Psychiatry , Korea University, College of Medicine , Republic of Korea
| | | | - Johannes Kornhuber
- p Department of Psychiatry and Psychotherapy , Friedrich-Alexander-University Erlangen-Nuremberg , Erlangen , Germany
| | | | - Berend Malchow
- a Department of Psychiatry and Psychotherapy , LMU Munich , Germany
| | - Juliana M Nascimento
- c Laboratory of Neuroproteomics, Department of Biochemistry , Institute of Biology University of Campinas (UNICAMP), Campinas , SP , Brazil
| | - Moritz Rossner
- r Department of Psychiatry, Molecular and Behavioural Neurobiology , LMU Munich , Germany.,s Research Group Gene Expression , Max Planck Institute of Experimental Medicine , Göttingen , Germany
| | - Markus Schwarz
- t Institute for Laboratory Medicine, LMU Munich , Germany
| | - Johann Steiner
- u Department of Psychiatry , University of Magdeburg , Magdeburg , Germany
| | - Leda Talib
- b Laboratory of Neuroscience (LIM27) , Institute of Psychiatry, University of Sao Paulo , Sao Paulo , Brazil
| | - Florence Thibaut
- v Department of Psychiatry , University Hospital Cochin (site Tarnier), University of Paris-Descartes, INSERM U 894 Centre Psychiatry and Neurosciences , Paris , France
| | - Peter Riederer
- w Center of Psychic Health; Department of Psychiatry, Psychosomatics and Psychotherapy , University Hospital of Würzburg , Germany
| | - Peter Falkai
- a Department of Psychiatry and Psychotherapy , LMU Munich , Germany
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Sanacora G, Rothman D, Krystal JH. Applications of Magnetic Resonance Spectroscopy to Psychiatry. Neuroscientist 2016. [DOI: 10.1177/107385849900500316] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The inaccessibility of the human brain to biochemical studies has historically challenged the ability of in vestigators to elucidate the pathophysiology of psychiatric syndromes. Magnetic resonance spectroscopy (MRS) now provides a noninvasive means of assessing neurochemistry in vivo. Since the first application of the technique to the study of the human brain, many new advances have been made. This new technology broadens the applications of the MRS. The major principles of the technique and compounds currently available for study are discussed in this article. A brief review of current and future applications of the technology to the field of psychiatry are discussed. NEUROSCIENTIST 5:192-196, 1999
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Affiliation(s)
- Gerard Sanacora
- Departments of Psychiatry and Internal Medicine Yale
University School of Medicine New Haven, Connecticut
| | - Douglas Rothman
- Departments of Psychiatry and Internal Medicine Yale
University School of Medicine New Haven, Connecticut
| | - John H. Krystal
- Departments of Psychiatry and Internal Medicine Yale
University School of Medicine New Haven, Connecticut
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Yuksel C, Tegin C, O'Connor L, Du F, Ahat E, Cohen BM, Ongur D. Phosphorus magnetic resonance spectroscopy studies in schizophrenia. J Psychiatr Res 2015; 68:157-66. [PMID: 26228415 DOI: 10.1016/j.jpsychires.2015.06.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 06/15/2015] [Accepted: 06/18/2015] [Indexed: 12/26/2022]
Abstract
Phosphorus magnetic resonance spectroscopy ((31)P MRS) allows in vivo quantification of phosphorus metabolites that are considered to be related to membrane turnover and energy metabolism. In schizophrenia (SZ), (31)P MRS studies found several abnormalities in different brain regions suggesting that alterations in these pathways may be contributing to the pathophysiology. In this paper, we systematically reviewed the (31)P MRS studies in SZ published to date by taking patient characteristics, medication status and brain regions into account. Publications written in English were searched on http://www.ncbi.nlm.nih.gov/pubmed/, by using the keywords 'phosphomonoester', 'phosphodiester', 'ATP', 'phosphocreatine', 'phosphocholine', 'phosphoethanolamine','glycerophosphocholine', 'glycerophosphoethanolamine', 'pH', 'schizophrenia', and 'MRS'. Studies that measured (31)P metabolites in SZ patients were included. This search identified 52 studies. Reduced PME and elevated PDE reported in earlier studies were not replicated in several subsequent studies. One relatively consistent pattern was a decrease in PDE in chronic patients in the subcortical structures. There were no consistent patterns for the comparison of energy related phosphorus metabolites between patients and controls. Also, no consistent pattern emerged in studies seeking relationship between (31)P metabolites and antipsychotic use and other clinical variables. Despite emerging patterns, methodological heterogeneities and shortcomings in this literature likely obscure consistent patterns among studies. We conclude with recommendations to improve study designs and (31)P MRS methods in future studies. We also stress the significance of probing into the dynamic changes in energy metabolism, as this approach reveals abnormalities that are not visible to steady-state measurements.
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Affiliation(s)
- Cagri Yuksel
- McLean Hospital, 115 Mill Street, Belmont, MA, USA; Harvard Medical School, 25 Shattuck Street, Boston, MA, USA.
| | - Cuneyt Tegin
- University of Louisville, Department of Psychiatry, 323 E. Chestnut Street, Louisville, KY, USA.
| | | | - Fei Du
- McLean Hospital, 115 Mill Street, Belmont, MA, USA; Harvard Medical School, 25 Shattuck Street, Boston, MA, USA.
| | - Ezgi Ahat
- Istanbul University, Cerrahpasa School of Medicine. Kocamustafapaşa Cad. No:53, Istanbul, Turkey.
| | - Bruce M Cohen
- McLean Hospital, 115 Mill Street, Belmont, MA, USA; Harvard Medical School, 25 Shattuck Street, Boston, MA, USA.
| | - Dost Ongur
- McLean Hospital, 115 Mill Street, Belmont, MA, USA; Harvard Medical School, 25 Shattuck Street, Boston, MA, USA.
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Smesny S, Kinder D, Willhardt I, Rosburg T, Lasch J, Berger G, Sauer H. Increased calcium-independent phospholipase A2 activity in first but not in multiepisode chronic schizophrenia. Biol Psychiatry 2005; 57:399-405. [PMID: 15705356 DOI: 10.1016/j.biopsych.2004.11.018] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2004] [Revised: 08/30/2004] [Accepted: 11/10/2004] [Indexed: 10/25/2022]
Abstract
BACKGROUND Increased activity of calcium independent phospholipase A2 (iPLA2) has repeatedly been found in the serum of unmedicated first-episode schizophrenia patients and assumed to reflect a pertubation of phospholipid metabolism. Previous studies in chronic schizophrenia were less conclusive. To explore whether iPLA2 changes are stage dependent, we investigated serum iPLA2 activity in various stages of schizophrenia. METHODS iPLA2 activity was assessed in the serum of 30 first-episode and 23 multiepisode schizophrenia patients and 53 healthy control subjects matched for age and gender. A fluorimetric assay was applied using the PLA2 specific substrate NBDC6-HPC, thin-layer chromatography of reaction products, and digital image scanning for signal detection. RESULTS Group comparison between first-episode and multiepisode patients and corresponding control groups revealed significantly increased iPLA2 activity only in first-episode patients. Enzyme activity in first-episode patients was also markedly increased, compared with chronic patients. iPLA2 changes observed were irrespective of neuroleptic medication, age, or gender. CONCLUSIONS Our results suggest increased lipid turnover in the acute early phase of schizophrenia that is less obvious in chronic stages. Future longitudinal studies involving iPLA2 activity and phosphorous magnetic resonance spectroscopy need to address the relation between perturbed brain lipid metabolism and iPLA2 increment in the course of schizophrenia.
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Affiliation(s)
- Stefan Smesny
- Department of Psychiatry, Friedrich-Schiller-University Jena, Jena, USA.
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Abstract
Magnetic resonance spectroscopy is a noninvasive investigative technique for in vivo detection of biochemical changes in neuropsychiatric disorders for which especially proton (1H-MRS) and phosphorus (31P-MRS) magnetic resonance spectroscopy have been used. In this review we explain the principles of MRS and summarize the studies in schizophrenia. A systematic literature review was carried out for 1H-MRS studies investigating schizophrenic patients compared to controls. The inconsistent results in the cited studies may be due to different study population, specific neuroimaging technique, and selected brain regions. Frequent findings are decreased PME and increased PDE concentrations (31P-MRS) linked to altered metabolism of membrane phospholipids and decreased N-acetylaspartate (NAA) or NAA/choline ratio (1H-MRS) linked to neuronal damage in frontal (DLPFC) or temporal regions in patients with schizophrenia. These results contribute to the disturbed frontotemporal-thalamic network assumed in schizophrenia and are supported by additional functional neuroimaging, MRI morphometry, and neuropsychological evaluation. The combination of the described investigative techniques with MRS in follow-up studies may provide more specific clues for understanding the pathogenesis and disease course in schizophrenia.
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Affiliation(s)
- T Wobrock
- Klinik für Psychiatrie und Psychotherapie, Universitätsklinikum des Saarlandes, Homburg/Saar.
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7
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Abstract
A variety of biochemical, clinical and genetic evidence suggests that phospholipid metabolism may play an aetiological role in schizophrenia. A key piece of evidence is the reduced vasodilatory response of patients with schizophrenia to nicotinic acid (NA). NA causes vasodilation via the activation of phospholipase A2 (PLA2) leading to the release of free fatty acids from membrane phospholipids and the subsequent production of prostaglandins. Insensitivity to NA may be due to a 'block' in the downstream signaling pathway used by the drug to evoke its response. It can be argued that if such an abnormality occurs in neurons, impaired PLA2-dependent signaling could result in altered glutamateric and dopaminergic transmission in such a way as to produce or exacerbate psychotic symptoms. The complimentary finding of increased PLA2 activity in schizophrenia may be an attempt to overcome the signaling block. It is suggested that intervention aimed at increasing the activity of PLA2-dependent signaling systems may be therapeutically useful in the treatment of the illness.
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Affiliation(s)
- Brian M Ross
- Ness Foundation, UNI Millennium Institute, Ness House, Dochgarroch, IV3 8GY, Inverness, Scotland, UK.
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8
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Berger GE, Wood SJ, Pantelis C, Velakoulis D, Wellard RM, McGorry PD. Implications of lipid biology for the pathogenesis of schizophrenia. Aust N Z J Psychiatry 2002; 36:355-66. [PMID: 12060184 DOI: 10.1046/j.1440-1614.2001.01021.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE Preclinical and clinical data suggest that lipid biology is integral to brain development and neurodegeneration. Both aspects are proposed as being important in the pathogenesis of schizophrenia. The purpose of this paper is to examine the implications of lipid biology, in particular the role of essential fatty acids (EFA), for schizophrenia. METHODS Medline databases were searched from 1966 to 2001 followed by the cross-checking of references. RESULTS Most studies investigating lipids in schizophrenia described reduced EFA, altered glycerophospholipids and an increased activity of a calcium-independent phospholipase A2 in blood cells and in post-mortem brain tissue. Additionally, in vivo brain phosphorus-31 Magnetic Resonance Spectroscopy (31P-MRS) demonstrated lower phosphomonoesters (implying reduced membrane precursors) in first- and multi-episode patients. In contrast, phosphodiesters were elevated mainly in first-episode patients (implying increased membrane breakdown products), whereas inconclusive results were found in chronic patients. EFA supplementation trials in chronic patient populations with residual symptoms have demonstrated conflicting results. More consistent results were observed in the early and symptomatic stages of illness, especially if EFA with a high proportion of eicosapentaenoic acid was used. CONCLUSION Peripheral blood cell, brain necropsy and 31P-MRS analysis reveal a disturbed lipid biology, suggesting generalized membrane alterations in schizophrenia. 31P-MRS data suggest increased membrane turnover at illness onset and persisting membrane abnormalities in established schizophrenia. Cellular processes regulating membrane lipid metabolism are potential new targets for antipsychotic drugs and might explain the mechanism of action of treatments such as eicosapentaenoic acid.
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Affiliation(s)
- Gregor E Berger
- Early Psychosis Prevention and Intervention Centre, MH-SKY (EPPIC), Victoria.
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Fukuzako H. Neurochemical investigation of the schizophrenic brain by in vivo phosphorus magnetic resonance spectroscopy. World J Biol Psychiatry 2001; 2:70-82. [PMID: 12587188 DOI: 10.3109/15622970109027496] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Abnormal phospholipid metabolisms may play important roles in the pathophysiology of schizophrenia. Phosphorus magnetic resonance spectroscopy (31P-MRS) offers a new method for studying phosphorus-related metabolism in vivo. A decrease in the level of phosphomonoesters (PME) and an increase in the level of phosphodiesters (PDE) has been demonstrated in the prefrontal lobe of neuroleptic-naive schizophrenic patients. Most of the studies in medicated schizophrenic patients have shown decreased PME and/or increased PDE. The decreased PME in the frontal lobe appears to be associated with negative symptoms and poor working memory performance. 1H-decoupled 31P-MRS revealed a reduction in the phosphocholine element of PME and an elevation in the mobile phospholipids of PDE in the prefrontal region of medicated schizophrenic patients. PDE were elevated in the temporal lobes of neuroleptic-naive schizophrenic patients, and this increase was partially normalized by haloperidol administration. Data about the temporal lobes of medicated schizophrenic patients have not been consistent. Except for the reduction in the adenosine triphosphate (ATP) in the basal ganglia and the correlation between the increase in the frontal lobe phosphocreatine (PCr) and negative symptomatology, data related to changes in high-energy phosphates are contradictory. No consensus on the effect of neuroleptics on phosphorus metabolites has been achieved. Methodological problems inherent in 31P-MRS may have contributed to the confusion in understanding available data. Future directions of MRS studies are suggested in the last section of the paper.
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Affiliation(s)
- H Fukuzako
- Department of Neuropsychiatry, Faculty of Medicine, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8520, Japan.
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Volz HR, Riehemann S, Maurer I, Smesny S, Sommer M, Rzanny R, Holstein W, Czekalla J, Sauer H. Reduced phosphodiesters and high-energy phosphates in the frontal lobe of schizophrenic patients: a (31)P chemical shift spectroscopic-imaging study. Biol Psychiatry 2000; 47:954-61. [PMID: 10838063 DOI: 10.1016/s0006-3223(00)00235-3] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND (31)Phosphorous magnetic resonance spectroscopy has been widely used to evaluate schizophrenic patients in comparison to control subjects, because it allows the investigation of both phospholipid and energy metabolism in vivo; however, the results achieved so far are inconsistent. Chemical shift imaging (CSI) has the advantage that instead of only one or a few preselected voxels the tissue of a whole brain slice can be examined. The aim of the present investigation was to determine whether the results of previous studies of our group, showing that phosphodiesters (PDE) are decreased in the frontal lobe of schizophrenic patients as compared to control subjects, might be confirmed in an independent unmedicated patient sample using the CSI technique. METHODS A carefully selected new cohort including 11 neuroleptic-free schizophrenic patients and 11 age- and gender-matched healthy control subjects was recruited. CSI was applied and an innovative analysis method for CSI data based on a general linear model was used. RESULTS PDE, phosphocreatine, and adenosine triphosphate (ATP) were found to be significantly decreased in the frontal lobe of patients with schizophrenia. CONCLUSIONS Because PDE was decreased in schizophrenic patients, the membrane phospholipid hypothesis of schizophrenia could not be corroborated. Further results indicate decreased ATP production in the frontal lobe of patients with schizophrenia.
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Affiliation(s)
- H R Volz
- Department of Psychiatry, University of Jena, Germany
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Ross BM, Turenne S, Moszczynska A, Warsh JJ, Kish SJ. Differential alteration of phospholipase A2 activities in brain of patients with schizophrenia. Brain Res 1999; 821:407-13. [PMID: 10064828 DOI: 10.1016/s0006-8993(99)01123-3] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
We recently reported that the activity of a calcium-independent subtype of phospholipase A2 is increased in blood of patients with schizophrenia. The present investigation examined whether similar changes take place in brain of patients with this disorder, and for comparison, in patients with bipolar disorder. The activity of two classes of PLA2, calcium-stimulated and independent, were assayed in autopsied temporal, prefrontal and occipital cortices, putamen, hippocampus and thalamus of 10 patients with schizophrenia, 8 patients with bipolar disorder and 12 matched control subjects. Calcium-independent PLA2 activity was increased by 45% in the temporal cortex of patients with schizophrenia as compared with the controls but was not significantly altered in other brain areas. In contrast, calcium-stimulated PLA2 activity was decreased by 27-42% in the temporal and prefrontal cortices and putamen, with no significant alterations in other brain regions. Brain PLA2 activity was normal in patients with bipolar disorder. Calcium-stimulated PLA2 activity was normal in cortex, cerebellum and striatum of rats treated acutely or chronically with haloperidol, whereas calcium-independent PLA2 activity was decreased in striatum of chronically treated animals, indicating that altered PLA2 activity in patients with schizophrenia is unlikely to be a direct effect of medication. Studies of the cellular role played by PLA2 suggest that decreased calcium-stimulated PLA2 activity, as also occurs in striatum of chronic human cocaine users, may be due, in part, to increased dopaminergic activity in the disorder, whereas increased calcium-independent PLA2 activity may be related to abnormal fatty acid metabolism and oxidative stress in schizophrenia.
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Affiliation(s)
- B M Ross
- Human Neurochemical Pathology Laboratory, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario, Canada.
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Kegeles LS, Humaran TJ, Mann JJ. In vivo neurochemistry of the brain in schizophrenia as revealed by magnetic resonance spectroscopy. Biol Psychiatry 1998; 44:382-98. [PMID: 9777167 DOI: 10.1016/s0006-3223(97)00425-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Magnetic resonance spectroscopy (MRS), an application of the methods of nuclear magnetic resonance (NMR), is a functional imaging modality that provides a view of localized biochemistry in vivo. A number of studies applying MRS to the neurochemistry of schizophrenia have been reported, which encompass a range of patient populations, states of medication, anatomic regions, nuclear species, and MRS techniques. A brief review of the history and methodology of NMR and MRS is presented. Comparison is made of MRS capabilities with other functional imaging modalities. Aspects of the neurochemistry of schizophrenia relevant to MRS studies are reviewed, as are the reported MRS studies involving patients with schizophrenia. Areas of consistent findings include decreased phosphomonoesters and increased phosphodiesters in frontal lobes, and decreases in the putative neuronal cell marker, N-acetylaspartate, in temporal lobes. Studies of neurotransmitters such as glutamate, gamma-aminobutyric acid, and glutamine have generated inconsistent results. New insights into alterations in neurochemistry in schizophrenia have been provided by MRS. Studies of neurotransmitters have future potential with improvements in field strength and in spectral editing techniques. MRS has the potential to measure brain medication levels and simultaneous effects on neurochemistry. MRS may assist in characterizing high-risk populations, and ultimately guide medication use.
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Affiliation(s)
- L S Kegeles
- Department of Psychiatry, Columbia University, New York, New York, USA
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Volz HP, Rzanny R, Rössger G, Hübner G, Kreitschmann-Andermahr I, Kaiser WA, Sauer H. 31Phosphorus magnetic resonance spectroscopy of the dorsolateral prefrontal region in schizophrenics--a study including 50 patients and 36 controls. Biol Psychiatry 1998; 44:399-404. [PMID: 9777168 DOI: 10.1016/s0006-3223(98)00061-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND In a preliminary study we found decreased phosphodiester (PDE)% values and an increased phosphomonoester (PME)/phosphodiester ratio in the dorsolateral prefrontal region (DLPFR) of 13 chronic schizophrenics vs. 14 controls using 31phosphorus magnetic resonance spectroscopy (31P-MRS). Since these results are in contrast to the findings of other groups, we increased our study group to a total of 50 chronic schizophrenics on stable neuroleptic medication and 36 controls to minimize the possibility of a chance result due to small sample size. METHODS An image-selected in vivo 31P-MRS method on a Philips Gyroscan ACS II scanner working at 1.5 T was used. RESULTS We could confirm our earlier findings of decreased PDE% levels in schizophrenics. Additionally, we found phosphocreatine (PCr)% and PCr/adenosine triphosphate (ATP) to be increased in the schizophrenics. While no association between PME% and PDE% with neuroleptic medication was found, ATP% correlated positively and PCr/ATP negatively with the chlorpromazine equivalent dose. CONCLUSIONS The decreased PDE% levels might be characteristic only for chronic, neuroleptic-treated patients. The finding of altered high-energy phosphate levels can be interpreted as an indication of decreased energy-demanding processes in the DLPFR of the investigated patients compared to controls.
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Affiliation(s)
- H P Volz
- Psychiatric Department, University of Jena, Germany
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Volz HP, Hübner G, Rzanny R, Rössger G, Preussler B, Eichhorn M, Kreitschmann-Andermahr I, Kaiser WA, Sauer H. High-energy phosphates in the frontal lobe correlate with Wisconsin Card Sort Test performance in controls, not in schizophrenics: a 31phosphorus magnetic resonance spectroscopic and neuropsychological investigation. Schizophr Res 1998; 31:37-47. [PMID: 9633835 DOI: 10.1016/s0920-9964(97)00157-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In recent years, a number of 31phosphorus magnetic resonance spectroscopy (P-MRS) studies on the frontal lobe of schizophrenics have been performed, reporting alterations of phospholipids and high-energy phosphates. Deicken et al. (1994b) recently found positive correlations between left frontal phosphomonoester% (PME%) levels and the performance of a specific frontal lobe task, the Wisconsin Card Sorting Test (WCST), in schizophrenics. In the present paper, the correlations between phospholipids and high-energy phosphates in the frontal lobe of 26 schizophrenics and 23 controls measured with a volume-selective P-MRS method were investigated. Overall, we could not find any correlations between WCST results and phospholipid levels, but in controls phosphocreatine% (PCr%) and PCr/adenenosine triphosphate (ATP) ratios were negatively correlated with test performance. Since PCr behaves as a buffer of ATP, in the sense that when ATP is consumed by neuronal activity PCr is catalysed rapidly to ATP, increased PCr% values and, moreover, increased PCr/ATP ratios point to a decreased ATP consumption. Thus, the correlations found between PCr% and PCr/ATP and test performance in controls point to an association between reduced performance in a specific frontal lobe task and decreased energy demanding processes at rest. This association was not found in schizophrenics, possibly due to the influence of neuroleptic medication or the disease process per se.
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Affiliation(s)
- H P Volz
- Department of Psychiatry, University of Jena, Germany.
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15
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Abstract
Technologic advances in functional brain imaging have provided exciting and informative insights into the functional neuroanatomy and neurochemistry of schizophrenia. Using MR spectroscopy, it has been possible to examine in vivo brain metabolism and to relate observed changes to physiological processes occurring at a cellular level. Positron emission tomography and single photon emission computed tomography have revealed disturbances of cerebral blood flow and glucose metabolism in patients with schizophrenia. More recently, these tools have also proved most useful in studying the relative receptor occupancy of typical and atypical antipsychotic medications.
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Affiliation(s)
- R J McClure
- Department of Psychiatry, University of Pittsburgh Medical Center, Pennsylvania, USA
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16
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Abstract
Neurobiological research in schizophrenia has been hampered by several confounding factors such as the heterogeneity of the illness and the paucity of biological markers. Recent progress in research methods, however, has enabled the improvement in our understanding its pathophysiology. This paper reviews recent neurochemical investigations of schizophrenia and its animal models which were conducted in Japan in the last decade. The research areas reviewed are (i) monoamine and their metabolites in body fluids, (ii) phospholipids and prostaglandins, (iii) neurochemistry in autopsy brains, (iv) immunological measures, (v) magnetic resonance spectroscopy, (vi) regional cerebral blood flows (rCBF), (vii) molecular genetics, and (viii) animal models. It is worth noting that there exist abnormalities of amino acidergic (glutamatergic and GABAergic) neurotransmission as well as monoaminergic (dopaminergic and serotonergic) one in postmortem schizophrenic brains. These abnormalities and also the findings of altered rCBF indicate the existence of disturbed neuronal circuits that contribute to the diverse symptoms of schizophrenia. Also, dysfunction of membrane phospholipids derived from studies on magnetic resonance spectroscopy may underlie negative symptoms in schizophrenia. Given that schizophrenia is considered to comprise a group of disorders with a diverse heterogeneity of etiologies, research in the next decade is expected to identify putative genes that are involved in vulnerability to schizophrenic phenotype.
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Affiliation(s)
- S Otsuki
- Zikei Institute of Psychiatry, Okayama, Japan
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17
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Fukuzako H, Fukuzako T, Takeuchi K, Ohbo Y, Ueyama K, Takigawa M, Fujimoto T. Phosphorus magnetic resonance spectroscopy in schizophrenia: correlation between membrane phospholipid metabolism in the temporal lobe and positive symptoms. Prog Neuropsychopharmacol Biol Psychiatry 1996; 20:629-40. [PMID: 8843487 DOI: 10.1016/0278-5846(96)00036-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
1. To determine any correlations between phosphorus metabolites in the temporal lobes and clinical symptoms in schizophrenic patients, the authors performed 31phosphorus magnetic resonance spectroscopy in 31 medicated patients and age- and sex- matched normal subjects. 2. Schizophrenic patients demonstrated an increased level of phosphodiesters (PDE) in the temporal lobes bilaterally and a decreased level of beta-adenosine triphosphate (beta-ATP) in the left temporal lobe. 3. A significant positive correlation was observed between the level of PDE in the left temporal lobe and the score of positive symptoms on the Brief Psychiatric Rating Scale. 4. These results suggest that altered membrane phospholipid metabolism in the left temporal lobe is associated with neuroleptic-resistant positive symptoms in schizophrenic patients.
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Affiliation(s)
- H Fukuzako
- Department of Neuropsychiatry, Faculty of Medicine, Kagoshima University, Japan
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18
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Fukuzako H, Takeuchi K, Hokazono Y, Fukuzako T, Yamada K, Hashiguchi T, Obo Y, Ueyama K, Takigawa M, Fujimoto T. Proton magnetic resonance spectroscopy of the left medial temporal and frontal lobes in chronic schizophrenia: preliminary report. Psychiatry Res 1995; 61:193-200. [PMID: 8748464 DOI: 10.1016/0925-4927(95)02622-5] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Proton magnetic resonance spectroscopy (MRS) was performed in 30 medicated schizophrenic patients and 30 normal subjects. Two groups, each containing 15 schizophrenic patients and 15 age-and sex-matched normal subjects, received MRS examinations for different volumes of interest, either the frontal lobe or the medial temporal lobe. Schizophrenic patients showed a decrease in the ratios of N-acetylaspartate (NAA)/choline-containing compounds (Cho) and NAA/creatine-phosphocreatine (Cr). The patients also showed an increase in the ratio of Cho/Cr in the left medial temporal lobe but not in the left frontal lobe. The age at onset of illness correlated positively with the ratios of NAA/Cho and NAA/Cr in the medial temporal lobe. No significant correlation was observed between the ratios of NAA/Cho, NAA/Cr, or Cho/Cr in the left medial temporal and frontal lobes and clinical symptomatology as assessed by the Scale for the Assessment of Negative Symptoms and the Positive and Negative Syndrome Scale.
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Affiliation(s)
- H Fukuzako
- Department of Neuropsychiatry, Faculty of Medicine, Kagoshima University, Japan
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