1
|
Yang Y, Jin X, Xue Y, Li X, Chen Y, Kang N, Yan W, Li P, Guo X, Luo B, Zhang Y, Liu Q, Shi H, Zhang L, Su X, Liu B, Lu L, Lv L, Li W. Right superior frontal gyrus: A potential neuroimaging biomarker for predicting short-term efficacy in schizophrenia. Neuroimage Clin 2024; 42:103603. [PMID: 38588618 PMCID: PMC11015154 DOI: 10.1016/j.nicl.2024.103603] [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: 01/11/2024] [Revised: 03/24/2024] [Accepted: 04/02/2024] [Indexed: 04/10/2024]
Abstract
Antipsychotic drug treatment for schizophrenia (SZ) can alter brain structure and function, but it is unclear if specific regional changes are associated with treatment outcome. Therefore, we examined the effects of antipsychotic drug treatment on regional grey matter (GM) density, white matter (WM) density, and functional connectivity (FC) as well as associations between regional changes and treatment efficacy. SZ patients (n = 163) and health controls (HCs) (n = 131) were examined by structural magnetic resonance imaging (sMRI) at baseline, and a subset of SZ patients (n = 77) were re-examined after 8 weeks of second-generation antipsychotic treatment to assess changes in regional GM and WM density. In addition, 88 SZ patients and 81 HCs were examined by resting-state functional MRI (rs-fMRI) at baseline and the patients were re-examined post-treatment to examine FC changes. The Positive and Negative Syndrome Scale (PANSS) and MATRICS Consensus Cognitive Battery (MCCB) were applied to measure psychiatric symptoms and cognitive impairments in SZ. SZ patients were then stratified into response and non-response groups according to PANSS score change (≥50 % decrease or <50 % decrease, respectively). The GM density of the right cingulate gyrus, WM density of the right superior frontal gyrus (SFG) plus 5 other WM tracts were reduced in the response group compared to the non-response group. The FC values between the right anterior cingulate and paracingulate gyrus and left thalamus were reduced in the entire SZ group (n = 88) after treatment, while FC between the right inferior temporal gyrus (ITG) and right medial superior frontal gyrus (SFGmed) was increased in the response group. There were no significant changes in regional FC among the non-response group after treatment and no correlations with symptom or cognition test scores. These findings suggest that the right SFG is a critical target of antipsychotic drugs and that WM density and FC alterations within this region could be used as potential indicators in predicting the treatment outcome of antipsychotics of SZ.
Collapse
Affiliation(s)
- Yongfeng Yang
- NHC Key Laboratory of Mental Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Peking University Sixth Hospital, Peking University Institute of Mental Health, Beijing 100191, China; Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China
| | - Xueyan Jin
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China
| | - Yongjiang Xue
- The Second Clinical College of Xinxiang Medical University, Xinxiang 453002, China
| | - Xue Li
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China
| | - Yi Chen
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China
| | - Ning Kang
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China
| | - Wei Yan
- NHC Key Laboratory of Mental Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Peking University Sixth Hospital, Peking University Institute of Mental Health, Beijing 100191, China
| | - Peng Li
- NHC Key Laboratory of Mental Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Peking University Sixth Hospital, Peking University Institute of Mental Health, Beijing 100191, China
| | - Xiaoge Guo
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China
| | - Binbin Luo
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China
| | - Yan Zhang
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China
| | - Qing Liu
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China
| | - Han Shi
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China
| | - Luwen Zhang
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China
| | - Xi Su
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China
| | - Bing Liu
- State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing 100875, China; Chinese Institute for Brain Research, Beijing 102206, China
| | - Lin Lu
- NHC Key Laboratory of Mental Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Peking University Sixth Hospital, Peking University Institute of Mental Health, Beijing 100191, China; National Institute on Drug Dependence, Beijing Key Laboratory of Drug Dependence, Peking University, Beijing 100191, China; Peking-Tsinghua Centre for Life Sciences and PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
| | - Luxian Lv
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China.
| | - Wenqiang Li
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453002, China; Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, International Joint Research Laboratory for Psychiatry and Neuroscience of Henan, Xinxiang 453002, China; Henan Collaborative Innovation Center of Prevention and Treatment of Mental Disorder, Xinxiang 453002, China.
| |
Collapse
|
2
|
Dell’Osso B, Carlotta Palazzo M, Carlo Altamura A. Neurodevelopmental and Neurodegenerative Alterations in the Pathophysiology of Schizophrenia: Focus on Neuro-Immuno-Inflammation. NEURODEGENER DIS 2018. [DOI: 10.1007/978-3-319-72938-1_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|
3
|
Kang E, Wen Z, Song H, Christian KM, Ming GL. Adult Neurogenesis and Psychiatric Disorders. Cold Spring Harb Perspect Biol 2016; 8:cshperspect.a019026. [PMID: 26801682 DOI: 10.1101/cshperspect.a019026] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Psychiatric disorders continue to be among the most challenging disorders to diagnose and treat because there is no single genetic or anatomical locus that is causative for the disease. Current treatments are often blunt tools used to ameliorate the most severe symptoms, at the risk of disrupting functional neural systems. There is a critical need to develop new therapeutic strategies that can target circumscribed functional or anatomical domains of pathology. Adult hippocampal neurogenesis may be one such domain. Here, we review the evidence suggesting that adult hippocampal neurogenesis plays a role in emotional regulation and forms of learning and memory that include temporal and spatial memory encoding and context discrimination, and that its dysregulation is associated with psychiatric disorders, such as affective disorders, schizophrenia, and drug addiction. Further, adult neurogenesis has proven to be an effective model to investigate basic processes of neuronal development and converging evidence suggests that aberrant neural development may be an etiological factor, even in late-onset diseases. Constitutive neurogenesis in the hippocampus of the mature brain reflects large-scale plasticity unique to this region and could be a potential hub for modulation of a subset of cognitive and affective behaviors that are affected by multiple psychiatric disorders.
Collapse
Affiliation(s)
- Eunchai Kang
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Zhexing Wen
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Hongjun Song
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 Graduate Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Kimberly M Christian
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Guo-Li Ming
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 Graduate Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| |
Collapse
|
4
|
Olanzapine-induced DNA methylation in the hippocampus and cerebellum in genes mapped to human 22q11 and implicated in schizophrenia. Psychiatr Genet 2015; 25:88-94. [PMID: 25415458 DOI: 10.1097/ypg.0000000000000069] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Although there is indirect evidence that the effects of antipsychotic drugs may involve modulation of dopamine transmission, their mechanism of action is poorly understood. We hypothesized that antipsychotic drugs mediate their effects by epigenetic modulation. Here, we tested the effect of an antipsychotic, olanzapine, on the DNA methylation status of genes following chronic treatment using rat-specific methylation arrays. METHODS Forty-eight hours after the last dose of olanzapine/vehicle, rats were habituated to an open-field activity-monitoring chamber for 30 min to verify whether stress-induced locomotor activity was reduced in olanzapine-treated rats. To test this hypothesis, we examined the effect of olanzapine, a commonly used atypical antipsychotic drug, on the DNA methylation status of 49 genes mapped to human 22q11 and implicated in schizophrenia. Genomic DNA isolated from the cerebellum, hippocampus, and liver of olanzapine-treated (n=2) and control (n=2) rats were analyzed using rat-specific methylation arrays. RESULTS Significantly reduced locomotor activity of olanzapine-treated rats confirmed the therapeutic efficacy of the drug administered. The effects of olanzapine have been shown through significantly increased (P<0.01) DNA methylation of genes affecting several networks mainly (i) neurological disease, inflammatory disease, and inflammatory response and (ii) cancer, cell death and survival, tumor morphology. Also, proline degradation and L-DOPA degradation were affected by olanzapine-induced DNA methylation. Further, from a set of genes in the 22q11.2 microdeletions that has been implicated previously in psychosis, 29 genes showed increased methylation following olanzapine treatment. CONCLUSION The results showed that considerable number of genes (34/49) mapped to human 22q11 and implicated in schizophrenia were affected by olanzapine-induced DNA methylation. The results suggest that DNA methylation may play a role in the therapeutic efficacy of olanzapine.
Collapse
|
5
|
Castellani CA, Melka MG, Diehl EJ, Laufer BI, O'Reilly RL, Singh SM. DNA methylation in psychosis: insights into etiology and treatment. Epigenomics 2015; 7:67-74. [PMID: 25687467 DOI: 10.2217/epi.14.66] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Evidence for involvement of DNA methylation in psychosis forms the focus of this perspective. Of interest are results from two independent sets of experiments including rats treated with antipsychotic drugs and monozygotic twins discordant for schizophrenia. The results show that DNA methylation is increased in rats treated with antipsychotic drugs, reflecting the global effect of the drugs. Some of these changes are also seen in affected schizophrenic twins that were treated with antipsychotics. The genes and pathways identified in the unrelated experiments are relevant to neurodevelopment and psychiatric disorders. The common cause is hypothesized to be aberrations resulting from medication use. However, this needs to be established by future studies that address the origin of methylation changes in psychosis.
Collapse
|
6
|
Lee H, Kang E, GoodSmith D, Yoon DY, Song H, Knierim JJ, Ming GL, Christian KM. DISC1-mediated dysregulation of adult hippocampal neurogenesis in rats. Front Syst Neurosci 2015; 9:93. [PMID: 26161071 PMCID: PMC4479724 DOI: 10.3389/fnsys.2015.00093] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 06/01/2015] [Indexed: 01/14/2023] Open
Abstract
Adult hippocampal neurogenesis, the constitutive generation of new granule cells in the dentate gyrus of the mature brain, is a robust model of neural development and its dysregulation has been implicated in the pathogenesis of psychiatric and neurological disorders. Previous studies in mice have shown that altered expression of Disrupted-In-Schizophrenia 1 (Disc1), the mouse homolog of a risk gene for major psychiatric disorders, results in several distinct morphological phenotypes during neuronal development. Although there are advantages to using rats over mice for neurophysiological studies, genetic manipulations have not been widely utilized in rat models. Here, we used a retroviral-mediated approach to knockdown DISC1 expression in dividing cells in the rat dentate gyrus and characterized the morphological development of adult-born granule neurons. Consistent with earlier findings in mice, we show that DISC1 knockdown in adult-born dentate granule cells in rats resulted in accelerated dendritic growth, soma hypertrophy, ectopic dendrites, and mispositioning of new granule cells due to overextended migration. Our study thus demonstrates that the Disc1 genetic manipulation approach used in prior mouse studies is feasible in rats and that there is a conserved biological function of this gene across species. Extending gene-based studies of adult hippocampal neurogenesis from mice to rats will allow for the development of additional models that may be more amenable to behavioral and in vivo electrophysiological investigations. These models, in turn, can generate additional insight into the systems-level mechanisms of how risk genes for complex psychiatric disorders may impact adult neurogenesis and hippocampal function.
Collapse
Affiliation(s)
- Heekyung Lee
- Krieger Mind/Brain Institute, Johns Hopkins University Baltimore, MD, USA
| | - Eunchai Kang
- Institute for Cell Engineering, Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Neurology, Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - Douglas GoodSmith
- Krieger Mind/Brain Institute, Johns Hopkins University Baltimore, MD, USA
| | - Do Yeon Yoon
- Department of Neurology, Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - Hongjun Song
- Institute for Cell Engineering, Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Neurology, Johns Hopkins University School of Medicine Baltimore, MD, USA ; The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - James J Knierim
- Krieger Mind/Brain Institute, Johns Hopkins University Baltimore, MD, USA ; The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - Guo-Li Ming
- Institute for Cell Engineering, Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Neurology, Johns Hopkins University School of Medicine Baltimore, MD, USA ; The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - Kimberly M Christian
- Institute for Cell Engineering, Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Neurology, Johns Hopkins University School of Medicine Baltimore, MD, USA
| |
Collapse
|
7
|
Crisafulli C, Drago A, Calabrò M, Spina E, Serretti A. A molecular pathway analysis informs the genetic background at risk for schizophrenia. Prog Neuropsychopharmacol Biol Psychiatry 2015; 59:21-30. [PMID: 25554435 DOI: 10.1016/j.pnpbp.2014.12.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 12/22/2014] [Accepted: 12/23/2014] [Indexed: 01/01/2023]
Abstract
BACKGROUND Schizophrenia is a complex mental disorder marked by severely impaired thinking, delusional thoughts, hallucinations and poor emotional responsiveness. The biological mechanisms that lead to schizophrenia may be related to the genetic background of patients. Thus, a genetic perspective may help to unravel the molecular pathways disrupted in schizophrenia. METHODS In the present work, we used a molecular pathway analysis to identify the molecular pathways associated with schizophrenia. We collected data of genetic loci previously associated with schizophrenia, identified the genes located in those positions and created the metabolic pathways that are related to those genes' products. These pathways were tested for enrichment (a number of SNPs associated with the phenotype significantly higher than expected by chance) in a sample of schizophrenic patients and controls (4486 and 4477, respectively). RESULTS The molecular pathway that resulted from the identification of all the genes located in the loci previously found to be associated with schizophrenia was found to be enriched, as expected (permutated p(10(6))=9.9999e-06).We found 60 SNPs amongst 30 different genes with a strong association with schizophrenia. The genes are related to the pathways related to neurodevelopment, apoptosis, vesicle traffic, immune response and MAPK cascade. CONCLUSIONS The pathway related to the toll-like receptor family seemed to play a central role in the modulation/connection of various pathways whose disruption leads to schizophrenia. This pathway is related to the innate immune system, further stressing the role of immunological-related events in increasing the risk to schizophrenia.
Collapse
Affiliation(s)
- Concetta Crisafulli
- Department of Biomedical Science and Morphological and Functional Images, University of Messina, Messina, Italy
| | - Antonio Drago
- Department of Biomedical and Neuromotor Sciences - DIBINEM, University of Bologna, Bologna, Italy; I.R.C.C.S. "San Giovanni di Dio", Fatebenefratelli, Brescia, Italy.
| | - Marco Calabrò
- Department of Biomedical Science and Morphological and Functional Images, University of Messina, Messina, Italy; Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy; IRCCS Centro Neurolesi "Bonino-Pulejo", Messina, Italy
| | - Edoardo Spina
- Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
| | - Alessandro Serretti
- Department of Biomedical and Neuromotor Sciences - DIBINEM, University of Bologna, Bologna, Italy
| |
Collapse
|
8
|
Mighdoll MI, Tao R, Kleinman JE, Hyde TM. Myelin, myelin-related disorders, and psychosis. Schizophr Res 2015; 161:85-93. [PMID: 25449713 DOI: 10.1016/j.schres.2014.09.040] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 09/18/2014] [Accepted: 09/21/2014] [Indexed: 12/14/2022]
Abstract
The neuropathological basis of schizophrenia and related psychoses remains elusive despite intensive scientific investigation. Symptoms of psychosis have been reported in a number of conditions where normal myelin development is interrupted. The nature, location, and timing of white matter pathology seem to be key factors in the development of psychosis, especially during the critical adolescent period of association area myelination. Numerous lines of evidence implicate myelin and oligodendrocyte function as critical processes that could affect neuronal connectivity, which has been implicated as a central abnormality in schizophrenia. Phenocopies of schizophrenia with a known pathological basis involving demyelination or dysmyelination may offer insights into the biology of schizophrenia itself. This article reviews the pathological changes in white matter of patients with schizophrenia, as well as demyelinating diseases associated with psychosis. In an attempt to understand the potential role of dysmyelination in schizophrenia, we outline the evidence from a number of both clinically-based and post-mortem studies that provide evidence that OMR genes are genetically associated with increased risk for schizophrenia. To further understand the implication of white matter dysfunction and dysmyelination in schizophrenia, we examine diffusion tensor imaging (DTI), which has shown volumetric and microstructural white matter differences in patients with schizophrenia. While classical clinical-neuropathological correlations have established that disruption in myelination can produce a high fidelity phenocopy of psychosis similar to schizophrenia, the role of dysmyelination in schizophrenia remains controversial.
Collapse
Affiliation(s)
- Michelle I Mighdoll
- Lieber Institute for Brain Development, Johns Hopkins Medical Institutions, 855 N. Wolfe Street, Suite 300, Baltimore, MD 21205, USA.
| | - Ran Tao
- Lieber Institute for Brain Development, Johns Hopkins Medical Institutions, 855 N. Wolfe Street, Suite 300, Baltimore, MD 21205, USA.
| | - Joel E Kleinman
- Lieber Institute for Brain Development, Johns Hopkins Medical Institutions, 855 N. Wolfe Street, Suite 300, Baltimore, MD 21205, USA.
| | - Thomas M Hyde
- Lieber Institute for Brain Development, Johns Hopkins Medical Institutions, 855 N. Wolfe Street, Suite 300, Baltimore, MD 21205, USA; Department of Psychiatry & Behavioral Sciences, Johns Hopkins Medical School, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins Medical School, Baltimore, MD 21205, USA.
| |
Collapse
|
9
|
Terzić T, Kastelic M, Dolžan V, Plesničar BK. Genetic variability testing of neurodevelopmental genes in schizophrenic patients. J Mol Neurosci 2014; 56:205-11. [PMID: 25529856 DOI: 10.1007/s12031-014-0482-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 12/14/2014] [Indexed: 10/24/2022]
Abstract
This study investigated the associations between single nucleotide polymorphisms in the neurodevelopmental Disrupted In Schizophrenia 1 (DISC1 ), neuregulin 1 (NRG1), brain-derived neurotrophic factor (BDNF) and NOTCH4 genes and the clinical symptoms and the occurrence of treatment-resistant schizophrenia in the Slovenian population. We included 138 schizophrenia patients, divided into treatment-responsive and treatment-resistant group and 94 healthy blood donors. All subjects were genotyped for eight polymorphisms (DISC1 rs6675281, DISC1 rs821616, NRG1 rs3735781, NRG1 rs3735782, NRG1 rs10503929, NRG1 rs3924999, BDNF rs6265, NOTCH rs367398) and investigated for associations with clinical variables. NOTCH4 rs367398 AA/AG was significantly associated with worse Positive and Negative Syndrome Scale (PANSS) and Clinical Global Impression (CGI) score. NOTCH4 rs367398 was not statistically significantly associated with the occurrence of treatment-resistant schizophrenia after the correction for multiple testing. Our data indicate that NOTCH4 polymorphism can influence clinical symptoms in Slovenian patients with schizophrenia.
Collapse
Affiliation(s)
- Tea Terzić
- University Psychiatric Clinic Ljubljana, Studenec 48, 1260, Ljubljana, Slovenia
| | | | | | | |
Collapse
|
10
|
Puetz V, Günther T, Kahraman-Lanzerath B, Herpertz-Dahlmann B, Konrad K. Neuropsychological Deficits in the Prodromal Phase and Course of an Early-Onset Schizophrenia. ZEITSCHRIFT FUR KINDER-UND JUGENDPSYCHIATRIE UND PSYCHOTHERAPIE 2014; 42:167-76. [DOI: 10.1024/1422-4917/a000286] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Objectives: Although clear advances have been achieved in the study of early-onset schizophrenia (EOS), little is known to date about premorbid and prodromal neuropsychological functioning in EOS. Method: Here, we report on a case of an adolescent male with EOS who underwent neuropsychological testing before and after illness onset. Results: Marked cognitive deficits in the domains of attention, set-shifting, and verbal memory were present both pre-onset and during the course of schizophrenia, though only deficits in verbal memory persisted after illness-onset and antipsychotic treatment. Conclusion: The findings of this case study suggest that impairments in the verbal memory domain are particularly prominent symptoms of cognitive impairment in prodromal EOS and persist in the course of the disorder, which further demonstrates the difficult clinical situation of adequate schooling opportunities for adolescent patients with EOS.
Collapse
Affiliation(s)
- Vanessa Puetz
- Child Neuropsychology Section, Department of Child and Adolescent Psychiatry, Psychotherapy and Psychosomatics, University Hospital Aachen, Germany
| | - Thomas Günther
- Child Neuropsychology Section, Department of Child and Adolescent Psychiatry, Psychotherapy and Psychosomatics, University Hospital Aachen, Germany
| | - Berrak Kahraman-Lanzerath
- Child Neuropsychology Section, Department of Child and Adolescent Psychiatry, Psychotherapy and Psychosomatics, University Hospital Aachen, Germany
| | - Beate Herpertz-Dahlmann
- Child Neuropsychology Section, Department of Child and Adolescent Psychiatry, Psychotherapy and Psychosomatics, University Hospital Aachen, Germany
- JARA Translational Brain Medicine, Aachen & Jülich, Germany
| | - Kerstin Konrad
- Child Neuropsychology Section, Department of Child and Adolescent Psychiatry, Psychotherapy and Psychosomatics, University Hospital Aachen, Germany
- JARA Translational Brain Medicine, Aachen & Jülich, Germany
| |
Collapse
|
11
|
Copy number variation distribution in six monozygotic twin pairs discordant for schizophrenia. Twin Res Hum Genet 2014; 17:108-20. [PMID: 24556202 DOI: 10.1017/thg.2014.6] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We have evaluated copy number variants (CNVs) in six monozygotic twin pairs discordant for schizophrenia. The data from Affymetrix® Human SNP 6.0 arrays™ were analyzed using Affymetrix® Genotyping Console™, Partek® Genomics Suite™, PennCNV, and Golden Helix SVS™. This yielded both program-specific and overlapping results. Only CNVs called by Affymetrix Genotyping Console, Partek Genomics Suite, and PennCNV were used in further analysis. This analysis included an assessment of calls in each of the six twin pairs towards identification of unique CNVs in affected and unaffected co-twins. Real time polymerase chain reaction (PCR) experiments confirmed one CNV loss at 7q11.21 that was found in the affected patient but not in the unaffected twin. The results identified CNVs and genes that were previously implicated in mental abnormalities in four of the six twin pairs. It included PYY (twin pairs 1 and 5), EPHA3 (twin pair 3), KIAA1211L (twin pair 4), and GPR139 (twin pair 5). They represent likely candidate genes and CNVs for the discordance of four of the six monozygotic twin pairs for this heterogeneous neurodevelopmental disorder. An explanation for these differences is ontogenetic de novo events that differentiate in the monozygotic twins during development.
Collapse
|
12
|
Neurodevelopment Alterations, Neurodegeneration, and Immunoinflammatory Patterns in the Pathophysiology of Schizophrenia. NEURODEGENER DIS 2014. [DOI: 10.1007/978-1-4471-6380-0_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
|
13
|
Siira V, Wahlberg KE, Hakko H, Tienari P. Stability in MMPI among adoptees with high and low genetic risk for schizophrenia and with low Communication Deviance of their adoptive parents. Psychiatry Res 2013; 210:69-74. [PMID: 23769394 DOI: 10.1016/j.psychres.2013.05.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 05/14/2013] [Accepted: 05/19/2013] [Indexed: 12/19/2022]
Abstract
Stability has been considered an important aspect of vulnerability to schizophrenia. The temporal stability of the scales in the Minnesota Multiphasic Personality Inventory (MMPI) was examined, using adoptees from the Finnish Adoptive Family Study of Schizophrenia. Adoptees who were high-risk (HR) offspring of biological mothers having a schizophrenia spectrum disorder (n=28) and low-risk (LR) controls (n=46) were evaluated using 15 MMPI scales at the initial assessment (HR, mean age 24 years; LR, mean age 23 years) and at the follow-up assessment after a mean interval of 11 years. Stability of the MMPI scales was also assessed in the groups of adoptees, assigned according to the adoptive parents'(n=44) communication style using Communication Deviance (CD) scale as an environmental factor. Initial Lie, Frequency, Correction, Psychopathic Deviate, Schizophrenia, Manifest Hostility, Hypomania, Phobias, Psychoticism, Religious Fundamentalism, Social Maladjustment, Paranoid Schizophrenia, Golden-Meehl Indicators, Schizophrenia Proneness and 8-6 scale scores significantly predicted the MMPI scores at the follow-up assessment indicating stability in the characteristics of thinking, affective expression, social relatedness and volition. Low CD in the family had an effect on the stabilization of personality traits such as social withdrawal and restricted affectivity assessed by Correction and Hostility.
Collapse
Affiliation(s)
- Virva Siira
- Department of Psychiatry, Institute of Clinical Medicine, University of Oulu, Box 5000, FI-90014, Finland.
| | | | | | | |
Collapse
|
14
|
Altamura AC, Pozzoli S, Fiorentini A, Dell'osso B. Neurodevelopment and inflammatory patterns in schizophrenia in relation to pathophysiology. Prog Neuropsychopharmacol Biol Psychiatry 2013; 42:63-70. [PMID: 23021973 DOI: 10.1016/j.pnpbp.2012.08.015] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 08/23/2012] [Accepted: 08/25/2012] [Indexed: 11/18/2022]
Abstract
As for other major psychoses, the etiology of schizophrenia still remains poorly understood, involving genetic and epigenetic mechanisms, as well as environmental contributions. In addition, immune alterations have been widely reported in schizophrenic patients, involving both the unspecific and specific pathways of the immune system, and suggesting that infectious/autoimmune processes play an important role in the etiopathogenesis of the disorder. Cytokines, in particular, are supposed to play a critical role in infectious and inflammatory processes, mediating the cross-talk between the brain and the immune system. In this perspective, even though mixed results have been reported, it seems that schizophrenia is associated with an imbalance in inflammatory cytokines. Alterations in the inflammatory and immune systems, moreover, seem to be already present in the early stages of schizophrenia and connected to the neurodevelopmental hypothesis of the disorder, identifying its roots in brain development abnormalities that do not manifest themselves until adolescence or early adulthood. At the same time, neuropathological and longitudinal studies in schizophrenia also support a neurodegenerative hypothesis and, more recently, a novel mixed hypothesis, integrating neurodevelopmental and neurodegenerative models, has been put forward. The present review aims to provide an updated overview of the connections between the immune and inflammatory alterations and the aforementioned hypotheses in schizophrenia.
Collapse
Affiliation(s)
- A Carlo Altamura
- Department of Psychiatry, University of Milan, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Via F. Sforza 35, 20122, Milano, Italy.
| | | | | | | |
Collapse
|
15
|
Zhang Y, Yan H, Tian L, Wang F, Lu T, Wang L, Yan J, Liu Q, Kang L, Ruan Y, Zhang D, Yue W. Association of MTHFR C677T polymorphism with schizophrenia and its effect on episodic memory and gray matter density in patients. Behav Brain Res 2013; 243:146-52. [PMID: 23318463 DOI: 10.1016/j.bbr.2012.12.061] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2012] [Revised: 12/19/2012] [Accepted: 12/24/2012] [Indexed: 10/27/2022]
Abstract
Growing evidence suggests that the methylenetetrahydrofolate reductase (MTHFR) may play a role in the pathogenesis of schizophrenia. Recent studies suggested that the MTHFR 677T, as a risk allele, has an impact on brain activation and memory function in schizophrenia patients. To confirm further the association between this functional polymorphism and schizophrenia, we detected genotypes of MTHFR C677T polymorphism in 1002 schizophrenic patients and 1036 controls of Chinese Han population, by using direct DNA sequencing method. To explore further effects of MTHFR C677T polymorphism on memory and brain function in schizophrenia, 33 schizophrenia patients and 29 healthy participants were selected from above samples to be assessed with MRI scanning and episodic memory (EM) examination. The case-control association study results showed that the MTHFR C677T was associated with schizophrenia (χ(2)=14.11, P=1.74 × 10(-4), OR=0.79; 95% CI=0.70-0.89). We also found that the MTHFR 677T allele had a load-dependent effect on EM in schizophrenic patients, but not in healthy control participants. Further analysis on gray matter density (GMD) revealed significant diagnostic effects in bilateral frontal cortices, bilateral insula, left medial temporal cortex and bilateral occipital cortices, effects of MTHFR genotype in the right insula, right inferior frontal gyrus, right rolandic opercula, right parahippocampal gyrus and right medial temporal pole, and effects of genotype-diagnosis interaction in the right temporal gyrus. Our findings suggested that the MTHFR 677T allele might have effect on risk of schizophrenia, memory impairment and GMD changes in patients.
Collapse
Affiliation(s)
- Yanling Zhang
- Institute of Mental Health, Peking University, Beijing, 100191, China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Thapar M, Covault J, Hesselbrock V, Bonkovsky HL. DNA methylation patterns in alcoholics and family controls. World J Gastrointest Oncol 2012; 4:138-44. [PMID: 22737275 PMCID: PMC3382660 DOI: 10.4251/wjgo.v4.i6.138] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Revised: 05/16/2012] [Accepted: 05/21/2012] [Indexed: 02/05/2023] Open
Abstract
AIM: To assess whether DNA methylation patterns in chronic alcoholics are different from non-alcoholic sibling controls.
METHODS: We examined the methylation patterns in DNA samples from 25 chronic alcoholics and 22 matched siblings as controls (one per family). DNA was extracted from peripheral blood and analyzed for differences in the methylation patterns after bisulfite-conversion. We used the Illumina GoldenGate Methylation Cancer Panel I (Illumina, San Diego, CA), which probes the methylation profile at 1505 CpG sites from 807 cancer related genes. We excluded the 84 X-chromosome CpG sites and 134 autosomal CpG sites that failed to show a within sample reliability score of at least 95% for all samples, leaving 1287 autosomal CpG sites (associated with 743 autosomal genes) with reliable signals for all samples. A methylation score was calculated as the average methylation for the 1287 CpG sites examined. Differences were assessed by a two-sample t-test. We also examined the average sib pair differences in methylation scores at each of the 1287 sites. All analyses were performed using SPSS, version 9.0, P < 0.05 was considered significant.
RESULTS: Methylation levels at the 1287 CpG sites averaged 28.2% for both alcoholics and controls. The mean difference in methylation scores between alcoholic and non-alcoholic sibs by CpG site was < 1% with small inter-individual variances; and only 5 CpG sites had an average sib difference > 5%. Subgroup analysis showed that methylation scores were significantly lower for the alcoholic-dependent subjects who smoked compared to their non-smoking unaffected siblings. Specifically, among smokers who are alcoholic, global methylation indices were significantly lower than in non-alcoholic sib controls, whereas among non-smoking alcoholics, the global indices were significantly higher (P = 0.008).
CONCLUSION: Although we observed no effect of alcoholism alone on DNA methylation, there is a decrease in alcoholics who smoke, suggesting a mechanism for alcohol-tobacco synergy for carcinogenesis.
Collapse
Affiliation(s)
- Manish Thapar
- Manish Thapar, Herbert L Bonkovsky, Department of Medicine, The University of Connecticut Health Center, Farmington, CT 06030, United States
| | | | | | | |
Collapse
|
17
|
Källstrand J, Nehlstedt SF, Sköld ML, Nielzén S. Lateral asymmetry and reduced forward masking effect in early brainstem auditory evoked responses in schizophrenia. Psychiatry Res 2012; 196:188-93. [PMID: 22326876 DOI: 10.1016/j.psychres.2011.08.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Accepted: 08/30/2011] [Indexed: 11/17/2022]
Abstract
Individuals diagnosed with schizophrenia show deficiencies of basic neurophysiological sorting mechanisms. This study further investigated this issue, focusing on the two phenomena, laterality of coding and auditory forward masking. A specific audiometric method for use in psychiatry was the measuring set up to register brain stem audiograms (ABRs). A sample of 49 schizophrenic patients was compared with three control groups consisting of healthy reference subjects (n=49), attention deficit hyperactivity disorder (ADHD) patients (n=29), Asperger syndrome (AS) patients (n=13) and drug-induced psychotic patients (n=14). Schizophrenic patients showed significant abnormal laterality of brainstem activity in wave II of the auditory brainstem response (ABR) in comparison with all other study groups. Forward masking effects in the superior olive complex were coded significantly differently by schizophrenic patients compared to control groups except for the AS group. The results suggest deficits in the coding of auditory stimuli in the lower parts of the auditory pathway in schizophrenia and indicate that increased peripheral lateral asymmetry and forward masking aberrances could be neurophysiological markers for the disorder.
Collapse
|
18
|
Lott SA, Burghardt PR, Burghardt KJ, Bly MJ, Grove TB, Ellingrod VL. The influence of metabolic syndrome, physical activity and genotype on catechol-O-methyl transferase promoter-region methylation in schizophrenia. THE PHARMACOGENOMICS JOURNAL 2012; 13:264-71. [PMID: 22391769 DOI: 10.1038/tpj.2012.6] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The catechol-O-methyl transferase (COMT) 158Val/Met variant has been suggested to play a role in COMT function. Epigenetic regulation of COMT may further influence the prevalence of metabolic syndrome in these patient populations. This study examined the correlation between COMT promoter methylation and metabolic syndrome in schizophrenia patients receiving atypical antipsychotic (AAP) therapy. DNA was extracted from peripheral blood samples of schizophrenia subjects screened for metabolic syndrome. Pyrosequencing was used to analyze two methylation sites of the soluble COMT (COMT-s) promoter region. Associations between AAP use, lifestyle variables, metabolic syndrome and COMT genotype with peak methylation values were analyzed. Data are reported in 85 subjects. Methylation on CpG site 1 had a mean of 79.08% (±4.71) and it was 12.43% (±1.19) on site 2. COMT genotype proved to be an indicator of COMT methylation status on site 1 (F(2, 84)=5.78, P=0.0044) and site 2 (F(2, 84),=3.79, P=0.027). A significant negative correlation between physical activity and COMT promoter region methylation was found in Val/Val homozygous patients (site 1: P=0.013 and site 2: P=0.019). Those homozygous for Met/Met showed a positive correlation between promoter site methylation and physical activity (site 1: P=0.027, site 2: P=0.005), and between CpG site methylation and metabolic syndrome (site 1: P=0.002; site 2: P=0.001). The results of this study suggest that COMT promoter region methylation is largely influenced by COMT genotype and that physical activity plays a significant role in epigenetic modulation of COMT.
Collapse
Affiliation(s)
- S A Lott
- Department of Clinical Social and Administrative Sciences, University of Michigan College of Pharmacy, Ann Arbor, MI, USA
| | | | | | | | | | | |
Collapse
|
19
|
Lin CH, Lane HY, Tsai GE. Glutamate signaling in the pathophysiology and therapy of schizophrenia. Pharmacol Biochem Behav 2011; 100:665-77. [PMID: 21463651 DOI: 10.1016/j.pbb.2011.03.023] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Revised: 03/14/2011] [Accepted: 03/28/2011] [Indexed: 11/26/2022]
Abstract
Glutamatergic neurotransmission, particularly through the N-methyl-d-aspartate (NMDA) receptor, has drawn attention for its role in the pathophysiology of schizophrenia. This paper reviews the neurodevelopmental origin and genetic susceptibility of schizophrenia relevant to NMDA neurotransmission, and discusses the relationship between NMDA hypofunction and different domains of symptom in schizophrenia as well as putative treatment modality for the disorder. A series of clinical trials and a meta-analysis which compared currently available NMDA-enhancing agents suggests that glycine, d-serine, and sarcosine are more efficacious than d-cycloserine in improving the overall psychopathology of schizophrenia without side effect or safety concern. In addition, enhancing glutamatergic neurotransmission via activating the AMPA receptor, metabotropic glutamate receptor or inhibition of d-amino acid oxidase (DAO) is also reviewed. More studies are needed to determine the NMDA vulnerability in schizophrenia and to confirm the long-term efficacy, functional outcome, and safety of these NMDA-enhancing agents in schizophrenic patients, particularly those with refractory negative and cognitive symptoms, or serious adverse effects while taking the existing antipsychotic agents.
Collapse
Affiliation(s)
- Chieh-Hsin Lin
- Department of Psychiatry, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | | | | |
Collapse
|
20
|
Lu L, Mamiya T, Koseki T, Mouri A, Nabeshima T. Genetic Animal Models of Schizophrenia Related with the Hypothesis of Abnormal Neurodevelopment. Biol Pharm Bull 2011; 34:1358-63. [DOI: 10.1248/bpb.34.1358] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Lingling Lu
- The Academic Frontier Project for Private University, Comparative Cognitive Science Institute, Meijo University
- Department of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Meijo University
| | - Takayoshi Mamiya
- The Academic Frontier Project for Private University, Comparative Cognitive Science Institute, Meijo University
- Department of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Meijo University
- Japanese Drug Organization for Appropriate Use and Research
| | - Takenao Koseki
- The Academic Frontier Project for Private University, Comparative Cognitive Science Institute, Meijo University
- Department of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Meijo University
| | - Akihiro Mouri
- The Academic Frontier Project for Private University, Comparative Cognitive Science Institute, Meijo University
- Department of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Meijo University
- Japanese Drug Organization for Appropriate Use and Research
| | - Toshitaka Nabeshima
- The Academic Frontier Project for Private University, Comparative Cognitive Science Institute, Meijo University
- Department of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Meijo University
- Japanese Drug Organization for Appropriate Use and Research
| |
Collapse
|
21
|
Tempier R, Hepp SL, Duncan CR, Rohr B, Hachey K, Mosier K. Patient-centered care in affective, non-affective, and schizoaffective groups: patients' opinions and attitudes. Community Ment Health J 2010; 46:452-60. [PMID: 20480394 DOI: 10.1007/s10597-010-9316-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2008] [Accepted: 04/28/2010] [Indexed: 01/17/2023]
Abstract
An outcome evaluation was conducted to obtain psychiatric inpatients' perspectives on acute care mental health treatment and services. The applicability of diagnostic categories based on affective, non-affective, and schizoaffective disorder were considered in the predictability of responses to treatment regimens and the related services provided in an inpatient psychiatric unit. A multidimensional approach was used to survey patients, which included the DAI-30, the BMQ, the SERVQUAL, and the CSQ-8. Overall, findings indicate that inpatient satisfaction could be improved with tailoring treatment to suit their respective symptoms. Furthermore, this exploratory study demonstrates some preliminary support for the inclusion of patients with a diagnosis of schizoaffective disorder as a separate group toward improving acute mental health care while hospitalized.
Collapse
Affiliation(s)
- Raymond Tempier
- Department of Psychiatry, University of Saskatchewan, Saskatoon, SK, Canada.
| | | | | | | | | | | |
Collapse
|
22
|
Wilson C, Terry AV. Neurodevelopmental animal models of schizophrenia: role in novel drug discovery and development. ACTA ACUST UNITED AC 2010; 4:124-37. [PMID: 20643635 DOI: 10.3371/csrp.4.2.4] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Schizophrenia is a devastating mental illness that is associated with a lifetime of disability. For patients to successfully function in society, the amelioration of disease symptoms is imperative. The recently published results of two large antipsychotic clinical trials (e.g., CATIE, CUtLASS) clearly exemplified the limitations of currently available treatment options for schizophrenia, and further highlighted the critical need for novel drug discovery and development in this field. One of the biggest challenges in schizophrenia-related drug discovery is to find an appropriate animal model of the illness so that novel hypotheses can be tested at the basic science level. A number of pharmacological, genetic, and neurodevelopmental models have been introduced; however, none of these models has been rigorously evaluated for translational relevance or to satisfy requirements of "face," "construct" and "predictive" validity. Given the apparent polygenic nature of schizophrenia and the limited translational significance of pharmacological models, neurodevelopmental models may offer the best chance of success. The purpose of this review is to provide a general overview of the various neurodevelopmental models of schizophrenia that have been introduced to date, and to summarize their behavioral and neurochemical phenotypes that may be useful from a drug discovery and development standpoint. While it may be that, in the final analysis, no single animal model will satisfy all the requirements necessary for drug discovery purposes, several of the models may be useful for modeling various phenomenological and pathophysiological components of schizophrenia that could be targeted independently with separate molecules or multi-target drugs.
Collapse
Affiliation(s)
- Christina Wilson
- Department of Pharmacology and Toxicology, School of Graduate Studies, Medical College of Georgia, Augusta, GA 30912-2300, USA
| | | |
Collapse
|
23
|
Lescai F, Franceschi C. The impact of phenocopy on the genetic analysis of complex traits. PLoS One 2010; 5:e11876. [PMID: 20686705 PMCID: PMC2912380 DOI: 10.1371/journal.pone.0011876] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Accepted: 07/02/2010] [Indexed: 02/02/2023] Open
Abstract
A consistent debate is ongoing on genome-wide association studies (GWAs). A key point is the capability to identify low-penetrance variations across the human genome. Among the phenomena reducing the power of these analyses, phenocopy level (PE) hampers very seriously the investigation of complex diseases, as well known in neurological disorders, cancer, and likely of primary importance in human ageing. PE seems to be the norm, rather than the exception, especially when considering the role of epigenetics and environmental factors towards phenotype. Despite some attempts, no recognized solution has been proposed, particularly to estimate the effects of phenocopies on the study planning or its analysis design. We present a simulation, where we attempt to define more precisely how phenocopy impacts on different analytical methods under different scenarios. With our approach the critical role of phenocopy emerges, and the more the PE level increases the more the initial difficulty in detecting gene-gene interactions is amplified. In particular, our results show that strong main effects are not hampered by the presence of an increasing amount of phenocopy in the study sample, despite progressively reducing the significance of the association, if the study is sufficiently powered. On the opposite, when purely epistatic effects are simulated, the capability of identifying the association depends on several parameters, such as the strength of the interaction between the polymorphic variants, the penetrance of the polymorphism and the alleles (minor or major) which produce the combined effect and their frequency in the population. We conclude that the neglect of the possible presence of phenocopies in complex traits heavily affects the analysis of their genetic data.
Collapse
Affiliation(s)
- Francesco Lescai
- Division of Research Strategy, University College London, London, United Kingdom.
| | | |
Collapse
|
24
|
Ethnic origin and increased risk for schizophrenia in immigrants to countries of recent and longstanding immigration. Acta Psychiatr Scand 2010; 121:325-39. [PMID: 20105146 DOI: 10.1111/j.1600-0447.2009.01535.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
OBJECTIVES Compare the risk for schizophrenia in immigrants to countries of recent and longstanding immigration. Compare prevalence and incidence rates in black subjects under different conditions. METHOD An electronic literature search was complemented by review articles and cross-references. Studies reporting standard diagnosis and incidence or prevalence rates were included. RESULTS Immigrants had an increased risk for schizophrenia in countries of longstanding immigration, but with lower risk ratios than in those of recent immigration. The risk was higher in black immigrants and the black population living in the United States. But incidence and prevalence rates in Africa and the Caribbean were similar to those of international studies. CONCLUSION Comparing the most recent generation of immigrants with descendants of previous ones may account for the lower risk ratios observed in countries of longstanding vs. recent immigration. Two neurobiological hypotheses are proposed to explain the epidemiological findings in black populations and in immigrants.
Collapse
|
25
|
Zhang C, Fang Y, Xie B, Cheng W, Du Y, Wang D, Yu S. DNA methyltransferase 3B gene increases risk of early onset schizophrenia. Neurosci Lett 2009; 462:308-11. [PMID: 19576953 DOI: 10.1016/j.neulet.2009.06.085] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 06/24/2009] [Accepted: 06/26/2009] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Consistent evidence indicated that aberrant DNA methylation may be involved in the development of schizophrenia. DNA methyltransferase 3B (DNMT3B) is the key methyltransferase in DNA methylation regulations. In this study, we investigated the association between DNMT3B polymorphisms and the susceptibility of early onset schizophrenia in Chinese Han population. METHODS Case-control (patients=381 and controls=472) and family based (trios=103) study was performed through genotyping two tag single nucleotide polymorphisms (rs2424908 and rs6119954) covering the whole DNMT3B gene. Single nucleotide polymorphism association and haplotype analysis were performed. RESULTS The frequency of G allele of rs6119954 was significantly higher in patients than that in controls (P=0.017). Genotype distribution of rs6119954 was significantly different between patients and controls (P=0.046). A haplotype-wise analysis revealed a higher frequency of the T-G (rs2424908-rs6119954) haplotype in patients than that in controls (P=0.033). In the transmission disequilibrium test analysis, G allele of rs6119954 was preferentially transmitted in the trios (P=0.030). CONCLUSION Our findings indicate that DNMT3B may be a candidate gene for susceptibility to early onset schizophrenia.
Collapse
Affiliation(s)
- Chen Zhang
- Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | | | | | | | | | | | | |
Collapse
|
26
|
Ballestar E. Epigenetics Lessons from Twins: Prospects for Autoimmune Disease. Clin Rev Allergy Immunol 2009; 39:30-41. [DOI: 10.1007/s12016-009-8168-4] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
27
|
Olié JP, Mouaffak F, Krebs MO, Lôo H. [Schizophrenia, a neurodevelopmental illness]. ANNALES PHARMACEUTIQUES FRANÇAISES 2009; 67:251-5. [PMID: 19596098 DOI: 10.1016/j.pharma.2009.02.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2009] [Accepted: 02/12/2009] [Indexed: 10/20/2022]
Abstract
SUMMARY Developmental anomalies have been identified as risk factors for a future schizophrenic illness: low weight at birth, congenital malformations, delayed motor and social learning. Cognitive deficits and neurological soft signs belong to the indices of the schizophrenic spectrum. Neuroimaging has visualized various structural abnormalities present from the very beginning of schizophrenia. These structural changes may represent an exacerbation of normal neurodevelopmental processes. Moreover, vulnerability genes for schizophrenia are involved at different stages of neurodevelopment: the best studied associations are dysfunctional variants of DISC-1 and neuroregulin-1 genes, the role of other genes (dysbindin, BDNF, reelin...) remaining more widely debated. Lastly, the observation of structural chromosomal anomalies in 15% of patients suffering from schizophrenia (versus 5% of controls), more frequent in early onset schizophrenia (32% of cases) suggests a neurodevelopmental cause. Such a dynamic understanding of schizophrenia is consistent with what we know about cerebral plasticity along the life span. This does not preclude the search for cues of degenerative mechanisms. The issue now is a better characterization of the vulnerable phenotype for screening procedures to be implemented prior to disease onset.
Collapse
Affiliation(s)
- J-P Olié
- Inserm U894, Center of Psychiatry and Neurosciences, Paris, France.
| | | | | | | |
Collapse
|
28
|
Singh SM, Castellani CA, O'Reilly RL. Copy number variation showers in schizophrenia: an emerging hypothesis. Mol Psychiatry 2009; 14:356-8. [PMID: 19139749 DOI: 10.1038/mp.2008.149] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Genetic discoveries on Schizophrenia remain challenging. Traditional approaches have provided clues, but no genes. Novel theories that must account for extensive heterogeneity, including high discordance of monozygotic (MZD) twins, are needed. To this end, the extensive repeats of the human genome may provide the predisposition for DNA replication errors operational at every cell cycle during meiosis and mitosis. These errors will shower the genome with replication errors including copy number variations. Depending on the timing and the genes involved, this will contribute to the mutational load and disease. The evidence for such a mechanism in schizophrenia is emerging.
Collapse
Affiliation(s)
- S M Singh
- University of Western Ontario, London, ON, Canada.
| | | | | |
Collapse
|
29
|
Murphy BC, O'Reilly RL, Singh SM. DNA methylation and mRNA expression of SYN III, a candidate gene for schizophrenia. BMC MEDICAL GENETICS 2008; 9:115. [PMID: 19102774 PMCID: PMC2630979 DOI: 10.1186/1471-2350-9-115] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Accepted: 12/22/2008] [Indexed: 01/26/2023]
Abstract
BACKGROUND The synapsin III (SYN III) gene on chromosome 22q is a candidate gene for schizophrenia susceptibility due to its chromosome location, neurological function, expression patterns and functional polymorphisms. METHODS This research has established the mRNA expression of SYN III in 22 adult human brain regions as well as the methylation specificity in the closest CpG island of this gene. The methylation specificity studied in 31 brain regions (from a single individual) was also assessed in 51 human blood samples (representing 20 people affected with schizophrenia and 31 normal controls) including a pair of monozygotic twin discordant for schizophrenia and 2 non-human primates. RESULTS The results show that the cytosine methylation in this genomic region is 1) restricted to cytosines in CpG dinucleotides 2) similar in brain regions and blood and 3) appears conserved in primate evolution. Two cytosines (cytosine 8 and 20) localized as the CpG dinucleotide are partially methylated in all brain regions studied. The methylation of these sites in schizophrenia and control blood samples was variable. While cytosine 8 was partially methylated in all samples, the distribution of partial to complete methylation at the cytosine 20 was 22:9 in controls as compared to 18:2 in schizophrenia (p = 0.82). Also, there is no difference in methylation between the affected and unaffected member of a monozygotic twin pair. CONCLUSION The variation in SYN III methylation studied is 1) not related to schizophrenia in the population sample or a monozygotic twin pair discordant for schizophrenia and 2) not related to the mRNA level of SYN IIIa in different human brain regions.
Collapse
Affiliation(s)
- Brenda C Murphy
- Molecular Genetics Unit, Department of Biology and Division of Medical Genetics, The University of Western Ontario, London, Ontario N6A 5B7, Canada.
| | | | | |
Collapse
|
30
|
Convergence and divergence in the etiology of myelin impairment in psychiatric disorders and drug addiction. Neurochem Res 2008; 33:1940-9. [PMID: 18404371 DOI: 10.1007/s11064-008-9693-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2008] [Accepted: 03/28/2008] [Indexed: 12/30/2022]
Abstract
Impairment of oligodendroglia (OL)-dependent myelination in the central nervous system (CNS) is a remarkable parallel recently identified in major psychiatric disorders and chronic drug abuse. Neuroimaging and neuropathological studies revealed myelin defects and microarray-profiling analysis demonstrated aberrant expression of myelin-related genes in schizophrenia (SZ), bipolar disorder (BD), major depressive disorder (MDD) and cocaine addiction. However, the etiology underlying myelin impairment in these clinically distinct subjects remains elusive. This article reviews myelin impairment in line with dopaminergic dysfunction, a prime neuropathophysiological trait shared in psychiatric disorders and drug abuse, as well as the genetic and epigenetic alterations associated with these diseases. The current findings support the hypothesis that aberrant dopamine (DA) action on OLs is a common pathologic mechanism for myelin impairment in the aforementioned mental morbidities, whereas inherited genetic variations that specifically affect OL development and myelinogenesis may further increase myelin vulnerability in psychiatric disorders. Importantly, OL defect is not only a pathological consequence but also a causative factor for dopaminergic dysfunction. Hence, myelin impairment is a key factor in the pathogenic loop of psychiatric diseases and drug addiction.
Collapse
|
31
|
Vercauteren FGG, Flores G, Ma W, Chabot JG, Geenen L, Clerens S, Fazel A, Bergeron JJM, Srivastava LK, Arckens L, Quirion R. An organelle proteomic method to study neurotransmission-related proteins, applied to a neurodevelopmental model of schizophrenia. Proteomics 2008; 7:3569-79. [PMID: 17907268 DOI: 10.1002/pmic.200700379] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Limited information is currently available on molecular events that underlie schizophrenia-like behaviors in animal models. Accordingly, we developed an organelle proteomic approach enabling the study of neurotransmission-related proteins in the prefrontal cortex (PFC) of postpubertal (postnatal day 60 (PD60)) neonatally ventral hippocampal (nVH) lesioned rats, an extensively used neurodevelopmental model of schizophrenia-like behaviors. The PFC was chosen because of its purported role in the etiology of the disease. Statistical analysis of 392 reproducible spots on 2-D organelle proteomic patterns revealed significant changes in intensity of 18 proteinous spots in plasma membrane-enriched fractions obtained from postpubertal nVH lesioned rats compared to controls. Mass spectrometric analysis and database searching allowed the identification of a single protein in each of the nine differential spots, including proteins of low abundance, such as neurocalcin delta. Most of the identified dysregulated proteins, including clathrin light chain B, syntaxin binding protein 1b and visinin-like protein 1 are known to be linked to various neurotransmitter systems and to play key roles in plasma membrane receptor expression and recycling as well as synaptic vesicle exocytosis/recycling. Organelle proteomic approaches have hence proved to be most useful to identify key proteins linked to a given behavior in animal models of brain diseases.
Collapse
Affiliation(s)
- Freya G G Vercauteren
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montréal, Québec, Canada
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Kanazawa T, Glatt SJ, Tsutsumi A, Kikuyama H, Koh J, Yoneda H, Tsuang MT. Schizophrenia is not associated with the functional candidate gene ERBB3: results from a case-control study. Am J Med Genet B Neuropsychiatr Genet 2007; 144B:113-6. [PMID: 16958035 DOI: 10.1002/ajmg.b.30367] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Increasing evidence has supported the hypothesis of a neurodevelopmental component in the etiology of schizophrenia. Recently, several independent microarray gene expression studies have revealed downregulated expression of myelin-related genes in the postmortem brains of schizophrenia patients. Complete myelination of the cortex has been observed to occur in late adolescence and early adulthood, which is typically the age of onset of schizophrenia. ERBB3 is a gene which has not only been found to be downregulated in schizophrenia simultaneously in three microarray studies, but also is a strong candidate because of its potential role in neurodevelopment as a receptor of NRG1. Therefore, we performed association analysis of seven nonsynonymous SNPs in this gene. Two SNPs in ERBB3 (rs773123 and rs2271188) were polymorphic in our samples, neither of which showed significant evidence of association with the illness (P = 0.639 and 0.561, respectively). Because replication across such studies is notoriously difficult, the microarray evidence implicating ERBB3 still strongly supports some role of this gene in schizophrenia. However, our failure to find genetic association suggests that the differential expression of ERBB3 in schizophrenia may be environmentally driven, or involve cis- or trans-acting genetic factors beyond the boundaries of the gene itself.
Collapse
Affiliation(s)
- Tetsufumi Kanazawa
- Department of Psychiatry, Center for Behavioral Genomics, University of California, San Diego, La Jolla, California 92093, USA.
| | | | | | | | | | | | | |
Collapse
|
33
|
Miles JH, Takahashi TN. Lack of association between Rh status, Rh immune globulin in pregnancy and autism. Am J Med Genet A 2007; 143A:1397-407. [PMID: 17508426 DOI: 10.1002/ajmg.a.31846] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Though causes of autism are considered largely genetic, considerable concern remains that exposure to Rh immune globulin (RhIg), which until 2001 in the United States contained the preservative thimerosal, can cause autism. To determine whether mothers of children with autism are more likely to be Rh negative (Rh(-)) or to have received RhIg preserved with thimerosal, which is 49.6% ethyl mercury, we surveyed families of children with an autism spectrum disorder (ASD) ascertained through a University-based autism clinic considered free of ascertainment biases related to type of autism or severity. Between 2004 and 2006, 305 mothers of 321 children with an ASD agreed to participate in a telephone interview. Analysis of complete records including the blood group status and RhIg exposure of 214 families showed that Rh(-) status is no higher in mothers of children with autism than in the general population, exposure to antepartum RhIg, preserved with thimerosal is no higher for children with autism and pregnancies are no more likely to be Rh incompatible. This was also true for autism subgroups defined by behavioral phenotype, gender, IQ, regressive onset, head circumference, dysmorphology, birth status, essential, or complex phenotype. These findings support the consensus that exposure to ethylmercury in thimerosal is not the cause of the increased prevalence of autism. These data are important not only for parents in this country but also for the international health community where thimerosal continues to be used to preserve multi-dose vials which in turn makes vaccines affordable.
Collapse
Affiliation(s)
- Judith H Miles
- Thompson Center for Autism and Neurodevelopmental Disorders, and Department of Child Health, University of Missouri Hospitals and Clinics, 1 Hospital Drive, Columbia, MO 65212, USA.
| | | |
Collapse
|
34
|
González-Hernández JA, Pita-Alcorta C, Cedeño IR. From genes to brain oscillations: Is the visual pathway the epigenetic clue to schizophrenia? Med Hypotheses 2006; 66:300-8. [PMID: 16199129 DOI: 10.1016/j.mehy.2005.07.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2005] [Accepted: 07/25/2005] [Indexed: 11/26/2022]
Abstract
Molecular data and gene expression data and recently mitochondrial genes and possible epigenetic regulation by non-coding genes is revolutionizing our views on schizophrenia. Genes and epigenetic mechanisms are triggered by cell-cell interaction and by external stimuli. A number of recent clinical and molecular observations indicate that epigenetic factors may be operational in the origin of the illness. Based on the molecular insights, gene expression profiles and epigenetic regulation of gene, we went back to the neurophysiology (brain oscillations) and found a putative role of the visual experiences (i.e. visual stimuli) as epigenetic factor. The functional evidences provided here, establish a direct link between the striate and extrastriate unimodal visual cortex and the neurobiology of the schizophrenia. This result support the hypothesis that 'visual experience' has a potential role as epigenetic factor and contribute to trigger and/or to maintain the progression of the schizophrenia. In this case, candidate genes sensible for the visual 'insult' may be located within the visual cortex including associative areas, while the integrity of the visual pathway before reaching the primary visual cortex is preserved. The same effect can be perceived if target genes are localised within the visual pathway, which actually, is more sensitive for 'insult' during the early life than the cortex per se. If this process affects gene expression at these sites a stably sensory specific 'insult', i.e. distorted visual information, is entering the visual system and expanded to fronto-temporo-parietal multimodal areas even from early maturation periods. The difference in the timing of postnatal neuroanatomical events between such areas and the primary visual cortex in humans (with the formers reaching the same development landmarks later in life than the latter) is 'optimal' to establish an abnormal 'cell- communication' mediated by the visual system that may further interfere with the local physiology. In this context the strategy to search target genes need to be rearrangement and redirected to visual-related genes. Otherwise, psychophysics studies combining functional neuroimage, and electrophysiology are strongly recommended, for the search of epigenetic clues that will allow to carrier gene association studies in schizophrenia.
Collapse
Affiliation(s)
- J A González-Hernández
- Department of Clinical Neurophysiology and Department of Psychiatry, Hermanos Ameijeiras Hospital, Havana 3, 10300, Cuba.
| | | | | |
Collapse
|
35
|
Lewis SJ, Zammit S, Gunnell D, Smith GD. A meta-analysis of the MTHFR C677T polymorphism and schizophrenia risk. Am J Med Genet B Neuropsychiatr Genet 2005; 135B:2-4. [PMID: 15729744 DOI: 10.1002/ajmg.b.30170] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Epigenetic mechanisms such as methylation of DNA, could lead to abnormal neurodevelopment and may be important in the etiology of schizophrenia. Maternal dietary folate intake may play a role in determining methylation levels. The MTHFR gene C677T polymorphism influences folate metabolism and intracellular availability of folate metabolites for methylation. We carried out a meta-analysis of MTHFR C677T genotype and schizophrenia risk, and found that TT homozygotes had a significantly increased risk, OR 1.48 (1.18-1.86). This supports the hypothesis that folate status is a determinant of schizophrenia risk. Larger studies of this issue are required, together with studies of maternal genotype which could identify whether maternal folate status during pregnancy is important.
Collapse
Affiliation(s)
- Sarah J Lewis
- Department of Social Medicine, University of Bristol, Bristol, United Kingdom.
| | | | | | | |
Collapse
|
36
|
Abstract
Neurodevelopmental models of schizophrenia that identify longitudinal precursors of illness have been of great heuristic importance focusing most etiologic research over the past two decades. These models have varied considerably with respect to specificity and timing of hypothesized genetic and environmental 'hits', but have largely focused on insults to prenatal brain development. With heritability around 80%, nongenetic factors impairing development must also be part of the model, and any model must also account for the wide range of age of onset. In recent years, longitudinal brain imaging studies of both early and adult (to distinguish from late ie elderly) onset populations indicate that progressive brain changes are more dynamic than previously thought, with gray matter volume loss particularly striking in adolescence and appearing to be an exaggeration of the normal developmental pattern. This supports an extended time period of abnormal neurodevelopment in schizophrenia in addition to earlier 'lesions'. Many subtle cognitive, motor, and behavioral deviations are seen years before illness onset, and these are more prominent in early onset cases. Moreover, schizophrenia susceptibility genes and chromosomal abnormalities, particularly as examined for early onset populations (ie GAD1, 22q11DS), are associated with premorbid neurodevelopmental abnormalities. Several candidate genes for schizophrenia (eg dysbindin) are associated with lower cognitive abilities in both schizophrenic and other pediatric populations more generally. Postmortem human brain and developmental animal studies document multiple and diverse effects of developmental genes (including schizophrenia susceptibility genes), at sequential stages of brain development. These may underlie the broad array of premorbid cognitive and behavioral abnormalities seen in schizophrenia, and neurodevelopmental disorders more generally. Increased specificity for the most relevant environmental risk factors such as exposure to prenatal infection, and their interaction with susceptibility genes and/or action through phase-specific altered gene expression now both strengthen and modify the neurodevelopmental theory of schizophrenia.
Collapse
Affiliation(s)
- J L Rapoport
- Child Psychiatry Branch, NIMH, NIH, Bethesda, MD 20892-1600, USA.
| | | | | | | |
Collapse
|
37
|
Murphy BC, O'Reilly RL, Singh SM. Site-specific cytosine methylation in S-COMT promoter in 31 brain regions with implications for studies involving schizophrenia. Am J Med Genet B Neuropsychiatr Genet 2005; 133B:37-42. [PMID: 15635661 DOI: 10.1002/ajmg.b.30134] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The catechol-o-methyltransferase (COMT) gene on chromosome 22q11 has been considered a strong candidate gene for schizophrenia (SZ) susceptibility. A functional Val/Met polymorphism in exon 4, with potential to affect COMT activity has been implicated in SZ, but the results remain inconclusive. We hypothesized that the association of COMT gene with SZ is not strictly a genetic alteration but could involve DNA methylation, as an epigenetic alteration. Thus, we chose to examine the cytosine DNA methylation profile of the human COMT promoter regions, which partially overlaps with the MB-COMT coding region and covers a total of 56 cytosines. Our analysis of 31 brain regions and 51 individual blood samples suggests that the cytosine methylation in his region is restricted to the CpG dinucleotides only. Also, the methylation pattern is nearly identical in the brain and blood with few exceptions. One cytosine (#27) is partially methylated in 5 brain regions and another cytosine (#23) is partially methylated in 81 of 82 samples studied. The exception being the blood DNA from a single SZ patient with prominent extreme negative symptoms, which was completely methylated. Interestingly, there was no difference in methylation at these sites in the blood DNA from three pairs of monozygotic twins discordant for SZ. The results support the use of blood DNA in methylation studies and rule out S-COMT promoter methylation as a common cause of SZ. The unique observation of a completely methylated cytosine 23 in one patient with SZ may have the potential to affect COMT mRNA transcription and gene activity, but remains to be evaluated.
Collapse
Affiliation(s)
- Brenda C Murphy
- Molecular Genetics Unit, Department of Biology and Division of Medical Genetics, The University of Western Ontario, London, Ontario, Canada
| | | | | |
Collapse
|