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Hernandez LM, Kim M, Zhang P, Bethlehem RAI, Hoftman G, Loughnan R, Smith D, Bookheimer SY, Fan CC, Bearden CE, Thompson WK, Gandal MJ. Multi-ancestry phenome-wide association of complement component 4 variation with psychiatric and brain phenotypes in youth. Genome Biol 2023; 24:42. [PMID: 36882872 PMCID: PMC9990244 DOI: 10.1186/s13059-023-02878-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 02/15/2023] [Indexed: 03/09/2023] Open
Abstract
BACKGROUND Increased expression of the complement component 4A (C4A) gene is associated with a greater lifetime risk of schizophrenia. In the brain, C4A is involved in synaptic pruning; yet, it remains unclear the extent to which upregulation of C4A alters brain development or is associated with the risk for psychotic symptoms in childhood. Here, we perform a multi-ancestry phenome-wide association study in 7789 children aged 9-12 years to examine the relationship between genetically regulated expression (GREx) of C4A, childhood brain structure, cognition, and psychiatric symptoms. RESULTS While C4A GREx is not related to childhood psychotic experiences, cognition, or global measures of brain structure, it is associated with a localized reduction in regional surface area (SA) of the entorhinal cortex. Furthermore, we show that reduced entorhinal cortex SA at 9-10 years predicts a greater number and severity of psychosis-like events at 1-year and 2-year follow-up time points. We also demonstrate that the effects of C4A on the entorhinal cortex are independent of genome-wide polygenic risk for schizophrenia. CONCLUSIONS Our results suggest neurodevelopmental effects of C4A on childhood medial temporal lobe structure, which may serve as a biomarker for schizophrenia risk prior to symptom onset.
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Affiliation(s)
- Leanna M. Hernandez
- Department of Psychiatry, Semel Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095 USA
| | - Minsoo Kim
- Department of Psychiatry, Semel Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095 USA
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095 USA
- Program in Neurobehavioral Genetics, Semel Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095 USA
| | - Pan Zhang
- Department of Psychiatry, Semel Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095 USA
| | - Richard A. I. Bethlehem
- University of Cambridge, Department of Psychiatry, Cambridge Biomedical Campus, Cambridge, CB2 0SZ UK
| | - Gil Hoftman
- Department of Psychiatry, Semel Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095 USA
| | - Robert Loughnan
- Population Neuroscience and Genetics Lab, University of California, San Diego, San Diego, CA 92093 USA
| | - Diana Smith
- Population Neuroscience and Genetics Lab, University of California, San Diego, San Diego, CA 92093 USA
| | - Susan Y. Bookheimer
- Department of Psychiatry, Semel Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095 USA
| | - Chun Chieh Fan
- Population Neuroscience and Genetics Lab, University of California, San Diego, San Diego, CA 92093 USA
| | - Carrie E. Bearden
- Department of Psychiatry, Semel Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095 USA
| | - Wesley K. Thompson
- Population Neuroscience and Genetics Lab, University of California, San Diego, San Diego, CA 92093 USA
| | - Michael J. Gandal
- Department of Psychiatry, Semel Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095 USA
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095 USA
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA USA
- Lifespan Brain Institute at Penn Med and the Children’s Hospital of Philadelphia, Philadelphia, PA USA
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA USA
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Mayilyan KR, Krarup A, Soghoyan AF, Jensenius JC, Sim RB. l-ficolin-MASP arm of the complement system in schizophrenia. Immunobiology 2023; 228:152349. [PMID: 36805857 DOI: 10.1016/j.imbio.2023.152349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 02/11/2023] [Indexed: 02/17/2023]
Abstract
The abnormal neurodevelopment secondary to in utero adversities, such as hypoxia, malnutrition and maternal infections, underlies schizophrenia (SZ) etiology. As the genes of MBL-associated serine proteases (MASP) of the complement lectin pathway, MASP1 and MASP2, are expressed in the developing cortex and are functionally important for neuronal migration, we hypothesize that the malfunction ofl-ficolin-MASP arm may also be involved in schizophrenia pathophysiology as it was shown for MBL-MASP complexes. We investigated serum l-ficolin and plasma MASP-2 levels, the activity of l-ficolin-bound MASP-2, as well as an array of the complement-related variables in chronic schizophrenic patients in the acute phase of the disease and controls without physical or mental diagnoses. The median concentration of l-ficolin in Armenian controls was 3.66 μg/ml and similar to those reported for other Caucasian populations. SZ-cases had ∼40 % increase in serum l-ficolin (median 5.08 μg/ml; P < 0.0024). In the pooled sample, l-ficolin level was higher in males than in females (P < 0.0031), but this gender dichotomy was not affecting the variable association with schizophrenia (P < 0.016). Remarkably, MASP-2 plasma concentration showed gender-dependent significant variability in the group of patients but not in controls. When adjusted for gender and gender*diagnosis interaction, a significantly high MASP-2 level in female patients versus female controls was observed (median: 362 ng/ml versus 260 ng/ml, respectively; P < 0.0020). A significant increase in l-ficolin-bound MASP-2 activity was also observed in schizophrenia (on the median, cases vs controls: 7.60 vs 6.50 RU; P < 0.021). Correlation analyses of the levels of l-ficolin and MASP-2, l-ficolin-(MASP-2) activity and the demographic data did not show any significant association with the age of individuals, family history, age at onset and duration of the illness, and smoking. Noteworthy, the levels of l-ficolin and MASP-2 in circulation were significantly associated with the type of schizophrenia (paranoid SZ-cases had much higher l-ficolin (P < 0.0035) and lower MASP-2 levels than the other types combined (P < 0.049)). Correlations were also found between: (i) the classical pathway functional activity and l-ficolin level (rs = 0.19, P < 0.010); (ii) the alternative pathway functional activity and MASP-2 level (rs = 0.26, P < 0.00035); (iii) the activity of l-ficolin-bound MASP2 and the downstream C2 component haemolytic activity (rs = -0.19, P < 0.017); and (iv) l-ficolin and the upstream C-reactive protein (CRP) serum concentrations (r = 0.28, P < 0.018). Overall, the results showed l-ficolin-related lectin pathway alterations in schizophrenia pathophysiology. It is likely that in addition to the MBL-MASP component over-activity reported previously, the alterations of the lectin pathway in schizophrenia also involve variations of l-ficolin-(MASP-2) on protein concentration and activity levels.
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Affiliation(s)
- Karine R Mayilyan
- MRC Immunochemistry Unit, Department of Biochemistry, Oxford University, Oxford, United Kingdom; Institute of Molecular Biology, Armenian National Academy of Sciences, Yerevan, Armenia; Department of Therapeutics, Faculty of General Medicine, University of Traditional Medicine, Yerevan, Armenia.
| | - Anders Krarup
- MRC Immunochemistry Unit, Department of Biochemistry, Oxford University, Oxford, United Kingdom
| | - Armen F Soghoyan
- Yerevan State Medical University, Health Ministry of Armenia, Yerevan, Armenia; Psychosocial Recovery Center, Yerevan, Armenia
| | | | - Robert B Sim
- MRC Immunochemistry Unit, Department of Biochemistry, Oxford University, Oxford, United Kingdom
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3
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Consolidation of metabolomic, proteomic, and GWAS data in connective model of schizophrenia. Sci Rep 2023; 13:2139. [PMID: 36747015 PMCID: PMC9901842 DOI: 10.1038/s41598-023-29117-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 01/31/2023] [Indexed: 02/08/2023] Open
Abstract
Despite of multiple systematic studies of schizophrenia based on proteomics, metabolomics, and genome-wide significant loci, reconstruction of underlying mechanism is still a challenging task. Combination of the advanced data for quantitative proteomics, metabolomics, and genome-wide association study (GWAS) can enhance the current fundamental knowledge about molecular pathogenesis of schizophrenia. In this study, we utilized quantitative proteomic and metabolomic assay, and high throughput genotyping for the GWAS study. We identified 20 differently expressed proteins that were validated on an independent cohort of patients with schizophrenia, including ALS, A1AG1, PEDF, VTDB, CERU, APOB, APOH, FASN, GPX3, etc. and almost half of them are new for schizophrenia. The metabolomic survey revealed 18 group-specific compounds, most of which were the part of transformation of tyrosine and steroids with the prevalence to androgens (androsterone sulfate, thyroliberin, thyroxine, dihydrotestosterone, androstenedione, cholesterol sulfate, metanephrine, dopaquinone, etc.). The GWAS assay mostly failed to reveal significantly associated loci therefore 52 loci with the smoothened p < 10-5 were fractionally integrated into proteome-metabolome data. We integrated three omics layers and powered them by the quantitative analysis to propose a map of molecular events associated with schizophrenia psychopathology. The resulting interplay between different molecular layers emphasizes a strict implication of lipids transport, oxidative stress, imbalance in steroidogenesis and associated impartments of thyroid hormones as key interconnected nodes essential for understanding of how the regulation of distinct metabolic axis is achieved and what happens in the conditioned proteome and metabolome to produce a schizophrenia-specific pattern.
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4
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Hemby SE, McIntosh S. Chronic haloperidol administration downregulates select BDNF transcript and protein levels in the dorsolateral prefrontal cortex of rhesus monkeys. Front Psychiatry 2023; 14:1054506. [PMID: 36816400 PMCID: PMC9932326 DOI: 10.3389/fpsyt.2023.1054506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 01/16/2023] [Indexed: 02/05/2023] Open
Abstract
Post-mortem studies in the prefrontal cortex and hippocampal formation from schizophrenia patients have revealed significant disruptions in the expression molecules associated with cytoarchitecture, synaptic structure, function, and plasticity, known to be regulated in part by brain derived neurotrophic factor (BDNF). Interestingly, several studies using postmortem brain tissue from individuals diagnosed with schizophrenia have revealed a significant reduction in BDNF mRNA and protein levels in the dorsolateral prefrontal cortex (DLPFC), hippocampus and related areas; however, differentiating the effects of illness from antipsychotic history has remained difficult. We hypothesized that chronic antipsychotic treatment may contribute to the altered BDNF mRNA and protein expression observed in post-mortem brains of individuals diagnosed with schizophrenia. To address the influence of antipsychotic administration on BDNF expression in the primate brain, rhesus monkeys orally administered haloperidol, clozapine, or vehicle twice daily for 180 days. We found BDNF splice variants 4 and 5 in the DLPFC and variant 2 in the EC were significantly down-regulated following chronic administration of haloperidol. In addition, proBDNF and mature BDNF expression in the DLPFC, but not the EC, were significantly reduced. Based on the known regulation of BDNF expression by BDNF-AS, we assessed the expression of this lncRNA and found expression was significantly upregulated in the DLPFC, but not EC. The results of the present study provide evidence of haloperidol-induced regulation of BDNF mRNA and protein expression in the DLFPC and suggest an important role for BDNF-AS in this regulation. Given the role of BDNF in synaptic plasticity, neuronal survival and maintenance, aberrant expression induced by haloperidol likely has significant ramifications for neuronal populations and circuits in primate cortex.
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Affiliation(s)
- Scott E Hemby
- Department of Basic Pharmaceutical Sciences, Fred Wilson School of Pharmacy, High Point University, High Point, NC, United States
| | - Scot McIntosh
- Department of Basic Pharmaceutical Sciences, Fred Wilson School of Pharmacy, High Point University, High Point, NC, United States
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5
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Khan AQ, Thielen L, Le Pen G, Krebs MO, Kebir O, Groh A, Deest M, Bleich S, Frieling H, Jahn K. Methylation pattern and mRNA expression of synapse-relevant genes in the MAM model of schizophrenia in the time-course of adolescence. SCHIZOPHRENIA (HEIDELBERG, GERMANY) 2022; 8:110. [PMID: 36481661 PMCID: PMC9732294 DOI: 10.1038/s41537-022-00319-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 11/16/2022] [Indexed: 12/13/2022]
Abstract
Schizophrenia is highly heritable and aggregating in families, but genetics alone does not exclusively explain the pathogenesis. Many risk factors, including childhood trauma, viral infections, migration, and the use of cannabis, are associated with schizophrenia. Adolescence seems to be the critical period where symptoms of the disease manifest. This work focuses on studying an epigenetic regulatory mechanism (the role of DNA methylation) and its interaction with mRNA expression during development, with a particular emphasis on adolescence. The presumptions regarding the role of aberrant neurodevelopment in schizophrenia were tested in the Methyl-Azoxy-Methanol (MAM) animal model. MAM treatment induces neurodevelopmental disruptions and behavioral deficits in off-springs of the treated animals reminiscent of those observed in schizophrenia and is thus considered a promising model for studying this pathology. On a gestational day-17, adult pregnant rats were treated with the antimitotic agent MAM. Experimental animals were divided into groups and subgroups according to substance treatment (MAM and vehicle agent [Sham]) and age of analysis (pre-adolescent and post-adolescent). Methylation and mRNA expression analysis of four candidate genes, which are often implicated in schizophrenia, with special emphasis on the Dopamine hypothesis i.e., Dopamine receptor D2 (Drd2), and the "co-factors" Disrupted in schizophrenia 1 (DISC1), Synaptophysin (Syp), and Dystrobrevin-binding protein 1 (Dtnbp1), was performed in the Gyrus cingulum (CING) and prefrontal cortex (PFC). Data were analyzed to observe the effect of substance treatment between groups and the impact of adolescence within-group. We found reduced pre-adolescent expression levels of Drd2 in both brain areas under the application of MAM. The "co-factor genes" did not show high deviations in mRNA expression levels but high alterations of methylation rates under the application of MAM (up to ~20%), which diminished in the further time course, reaching a comparable level like in Sham control animals after adolescence. The pre-adolescent reduction in DRD2 expression might be interpreted as downregulation of the receptor due to hyperdopaminergic signaling from the ventral tegmental area (VTA), eventually even to both investigated brain regions. The notable alterations of methylation rates in the three analyzed co-factor genes might be interpreted as attempt to compensate for the altered dopaminergic neurotransmission.
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Affiliation(s)
- Abdul Qayyum Khan
- grid.10423.340000 0000 9529 9877Laboratory for Molecular Neurosciences (LMN), Department of Psychiatry, Social Psychiatry and Psychotherapy, Medical School Hannover (MHH), Carl-Neuberg-Str. 1, 30625 Hannover, Germany ,grid.444940.9University of Management and Technology—School of Pharmacy, 72-A Raiwind Rd, Dubai Town, Lahore Pakistan
| | - Lukas Thielen
- grid.10423.340000 0000 9529 9877Laboratory for Molecular Neurosciences (LMN), Department of Psychiatry, Social Psychiatry and Psychotherapy, Medical School Hannover (MHH), Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Gwenaëlle Le Pen
- grid.512035.0Université Paris Cité, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM, Pathophysiology of Psychiatric disorders: Development and Vulnerability, U1266, 102-108 Rue de la Santé, 75014 Paris, France
| | - Marie-Odile Krebs
- grid.512035.0Université Paris Cité, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM, Pathophysiology of Psychiatric disorders: Development and Vulnerability, U1266, 102-108 Rue de la Santé, 75014 Paris, France ,GHU Paris Psychiatrie et Neurosciences, 1 Rue Cabanis, 75014 Paris, France
| | - Oussama Kebir
- grid.512035.0Université Paris Cité, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM, Pathophysiology of Psychiatric disorders: Development and Vulnerability, U1266, 102-108 Rue de la Santé, 75014 Paris, France ,GHU Paris Psychiatrie et Neurosciences, 1 Rue Cabanis, 75014 Paris, France
| | - Adrian Groh
- grid.10423.340000 0000 9529 9877Laboratory for Molecular Neurosciences (LMN), Department of Psychiatry, Social Psychiatry and Psychotherapy, Medical School Hannover (MHH), Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Maximilian Deest
- grid.10423.340000 0000 9529 9877Laboratory for Molecular Neurosciences (LMN), Department of Psychiatry, Social Psychiatry and Psychotherapy, Medical School Hannover (MHH), Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Stefan Bleich
- grid.10423.340000 0000 9529 9877Laboratory for Molecular Neurosciences (LMN), Department of Psychiatry, Social Psychiatry and Psychotherapy, Medical School Hannover (MHH), Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Helge Frieling
- grid.10423.340000 0000 9529 9877Laboratory for Molecular Neurosciences (LMN), Department of Psychiatry, Social Psychiatry and Psychotherapy, Medical School Hannover (MHH), Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Kirsten Jahn
- grid.10423.340000 0000 9529 9877Laboratory for Molecular Neurosciences (LMN), Department of Psychiatry, Social Psychiatry and Psychotherapy, Medical School Hannover (MHH), Carl-Neuberg-Str. 1, 30625 Hannover, Germany
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6
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Lee J, Song S, Lee J, Kang J, Choe EK, Lee TY, Chon MW, Kim M, Kim SW, Chun MS, Chang MS, Kwon JS. Impaired migration of autologous induced neural stem cells from patients with schizophrenia and implications for genetic risk for psychosis. Schizophr Res 2022; 246:225-234. [PMID: 35810486 DOI: 10.1016/j.schres.2022.06.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 04/27/2022] [Accepted: 06/22/2022] [Indexed: 01/27/2023]
Abstract
Stem cell technologies have presented explicit evidence of the neurodevelopmental hypothesis of schizophrenia. However, few studies investigated relevance of the schizophrenia genetic liability and the use of genetic reprogramming on pluripotent stem cells to the impaired neurodevelopment shown by stem cells. Therefore, this study sought to investigate the cellular phenotypes of induced neural stem cells (iNSCs) derived without genetic modification from patients with schizophrenia and from genetic high risk (GHR) individuals. Three patients with a diagnosis of schizophrenia, 3 GHR individuals who had two or more relatives with schizophrenia, and 3 healthy volunteers participated. iNSCs were derived using a small molecule-based lineage switch method, and their gene expression levels and migration capabilities were examined. Demographic characteristics were not different among the groups (age, χ2 = 5.637, P = .060; education, χ2 = 2.111, P = .348). All participants stayed well during the follow-up except one GHR individual who developed psychosis 1.5 years later. Migration capacity was impaired in iNSCs from patients with schizophrenia (SZ-iNSCs) compared to iNSCs from GHR individuals or controls (P < .001). iNSCs from a GHR individual who later developed schizophrenia showed migratory impairment that was similar to SZ-iNSCs. Gene expression levels of Sox2 in SZ-iNSCs were significantly lower than those in controls (P = .028). Defective migration in genetically unmodified SZ-iNSCs is the first direct demonstration of neurodevelopmental abnormalities in schizophrenia. Additionally, alterations in gene expression in SZ-iNSCs suggest mechanisms by which genetic liability leads to aberrant neurodevelopment.
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Affiliation(s)
- Junhee Lee
- Institute of Human Behavioral Medicine, Medical Research Center, Seoul National University, 03080 Seoul, Republic of Korea; Department of Psychiatry, Uijeongbu Eulji Medical Center, 11759 Uijeongbu, Republic of Korea
| | - Sehyeon Song
- Laboratory of Stem Cell & Neurobiology, Department of Oral Anatomy, Dental Research Institute and School of Dentistry, Seoul National University, 03080 Seoul, Republic of Korea; Interdisciplinary Program in Neuroscience, Seoul National University College of Natural Sciences, 08826 Seoul, Republic of Korea
| | - Juhee Lee
- Laboratory of Stem Cell & Neurobiology, Department of Oral Anatomy, Dental Research Institute and School of Dentistry, Seoul National University, 03080 Seoul, Republic of Korea
| | - Jisoo Kang
- Laboratory of Stem Cell & Neurobiology, Department of Oral Anatomy, Dental Research Institute and School of Dentistry, Seoul National University, 03080 Seoul, Republic of Korea
| | - Eun Kyung Choe
- Department of Surgery, Seoul National University Hospital Healthcare System Gangnam Center, 06236 Seoul, Republic of Korea
| | - Tae Young Lee
- Department of Neuropsychiatry, Pusan National University Yangsan Hospital, 50612 Yangsan, Republic of Korea
| | - Myong-Wuk Chon
- National Center for Mental Health, 04933 Seoul, Republic of Korea
| | - Minah Kim
- Department of Psychiatry, Seoul National University College of Medicine, 03080 Seoul, Republic of Korea
| | - Seong Who Kim
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, 05505 Seoul, Republic of Korea
| | - Myung-Suk Chun
- National Agenda Research Division, Korea Institute of Science and Technology, 02792 Seoul, Republic of Korea
| | - Mi-Sook Chang
- Laboratory of Stem Cell & Neurobiology, Department of Oral Anatomy, Dental Research Institute and School of Dentistry, Seoul National University, 03080 Seoul, Republic of Korea; Interdisciplinary Program in Neuroscience, Seoul National University College of Natural Sciences, 08826 Seoul, Republic of Korea; Neuroscience Research Institute, Seoul National University, 03080 Seoul, Republic of Korea.
| | - Jun Soo Kwon
- Institute of Human Behavioral Medicine, Medical Research Center, Seoul National University, 03080 Seoul, Republic of Korea; Department of Psychiatry, Seoul National University College of Medicine, 03080 Seoul, Republic of Korea; Department of Brain and Cognitive Sciences, Seoul National University College of Natural Sciences, 08826 Seoul, Republic of Korea.
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7
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Šimić G, Krsnik Ž, Knezović V, Kelović Z, Mathiasen ML, Junaković A, Radoš M, Mulc D, Španić E, Quattrocolo G, Hall VJ, Zaborszky L, Vukšić M, Olucha Bordonau F, Kostović I, Witter MP, Hof PR. Prenatal development of the human entorhinal cortex. J Comp Neurol 2022; 530:2711-2748. [DOI: 10.1002/cne.25344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 04/30/2022] [Accepted: 05/02/2022] [Indexed: 11/11/2022]
Affiliation(s)
- Goran Šimić
- Department of Neuroscience Croatian Institute for Brain Research University of Zagreb Medical School, Zagreb, HR Croatia
| | - Željka Krsnik
- Department of Neuroscience Croatian Institute for Brain Research University of Zagreb Medical School, Zagreb, HR Croatia
| | - Vinka Knezović
- Department of Neuroscience Croatian Institute for Brain Research University of Zagreb Medical School, Zagreb, HR Croatia
| | - Zlatko Kelović
- Department of Anatomy University of Zagreb Medical School, Zagreb, HR Croatia
| | - Mathias Lysholt Mathiasen
- Department of Veterinary and Animal Sciences Faculty of Health Sciences University of Copenhagen, Frederiksberg C, DK Denmark
| | - Alisa Junaković
- Department of Neuroscience Croatian Institute for Brain Research University of Zagreb Medical School, Zagreb, HR Croatia
| | - Milan Radoš
- Department of Neuroscience Croatian Institute for Brain Research University of Zagreb Medical School, Zagreb, HR Croatia
| | - Damir Mulc
- Psychiatric Hospital Vrapče University of Zagreb Medical School, Zagreb, HR Croatia
| | - Ena Španić
- Department of Neuroscience Croatian Institute for Brain Research University of Zagreb Medical School, Zagreb, HR Croatia
| | - Giulia Quattrocolo
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation Norwegian University of Science and Technology Trondheim NO Norway
| | - Vanessa Jane Hall
- Department of Veterinary and Animal Sciences Faculty of Health Sciences University of Copenhagen, Frederiksberg C, DK Denmark
| | - Laszlo Zaborszky
- Center for Molecular and Behavioral Neuroscience Rutgers, The State University of New Jersey Newark New Jersey USA
| | - Mario Vukšić
- Department of Neuroscience Croatian Institute for Brain Research University of Zagreb Medical School, Zagreb, HR Croatia
| | - Francisco Olucha Bordonau
- Department of Medicine School of Medical Sciences Universitat Jaume I Castellón de la Plana ES Spain
| | - Ivica Kostović
- Department of Neuroscience Croatian Institute for Brain Research University of Zagreb Medical School, Zagreb, HR Croatia
| | - Menno P. Witter
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation Norwegian University of Science and Technology Trondheim NO Norway
| | - Patrick R. Hof
- Nash Family Department of Neuroscience and Friedman Brain Institute Icahn School of Medicine at Mount Sinai New York New York USA
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8
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Saleem A, Qurat-ul-Ain, Akhtar MF. Alternative Therapy of Psychosis: Potential Phytochemicals and Drug Targets in the Management of Schizophrenia. Front Pharmacol 2022; 13:895668. [PMID: 35656298 PMCID: PMC9152363 DOI: 10.3389/fphar.2022.895668] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 04/18/2022] [Indexed: 11/25/2022] Open
Abstract
Schizophrenia is a chronic mental and behavioral disorder characterized by clusters of symptoms including hallucinations, delusions, disorganized thoughts and social withdrawal. It is mainly contributed by defects in dopamine, glutamate, cholinergic and serotonergic pathways, genetic and environmental factors, prenatal infections, oxidative stress, immune system activation and inflammation. Management of schizophrenia is usually carried out with typical and atypical antipsychotics, but it yields modest benefits with a diversity of side effects. Therefore, the current study was designed to determine the phytochemicals as new drug candidates for treatment and management of schizophrenia. These phytochemicals alter and affect neurotransmission, cell signaling pathways, endocannabinoid receptors, neuro-inflammation, activation of immune system and status of oxidative stress. Phytochemicals exhibiting anti-schizophrenic activity are mostly flavonoids, polyphenols, alkaloids, terpenoids, terpenes, polypropanoids, lactones and glycosides. However, well-designed clinical trials are consequently required to investigate potential protective effect and therapeutic benefits of these phytochemicals against schizophrenia.
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Affiliation(s)
- Ammara Saleem
- Department of Pharmacology, Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | - Qurat-ul-Ain
- Department of Pharmacology, Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad, Pakistan
- Riphah Institute of Pharmaceutical Sciences, Riphah International University, Lahore, Pakistan
| | - Muhammad Furqan Akhtar
- Riphah Institute of Pharmaceutical Sciences, Riphah International University, Lahore, Pakistan
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9
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Magdalon J, Mansur F, Teles E Silva AL, de Goes VA, Reiner O, Sertié AL. Complement System in Brain Architecture and Neurodevelopmental Disorders. Front Neurosci 2020; 14:23. [PMID: 32116493 PMCID: PMC7015047 DOI: 10.3389/fnins.2020.00023] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 01/10/2020] [Indexed: 01/18/2023] Open
Abstract
Current evidence indicates that certain immune molecules such as components of the complement system are directly involved in neurobiological processes related to brain development, including neurogenesis, neuronal migration, synaptic remodeling, and response to prenatal or early postnatal brain insults. Consequently, complement system dysfunction has been increasingly implicated in disorders of neurodevelopmental origin, such as schizophrenia, autism spectrum disorder (ASD) and Rett syndrome. However, the mechanistic evidence for a causal relationship between impaired complement regulation and these disorders varies depending on the disease involved. Also, it is still unclear to what extent altered complement expression plays a role in these disorders through inflammation-independent or -dependent mechanisms. Furthermore, pathogenic mutations in specific complement components have been implicated in the etiology of 3MC syndrome, a rare autosomal recessive developmental disorder. The aims of this review are to discuss the current knowledge on the roles of the complement system in sculpting brain architecture and function during normal development as well as after specific inflammatory insults, such as maternal immune activation (MIA) during pregnancy, and to evaluate the existing evidence associating aberrant complement with developmental brain disorders.
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Affiliation(s)
- Juliana Magdalon
- Center for Experimental Research, Hospital Israelita Albert Einstein, São Paulo, Brazil.,School of Medicine, Faculdade Israelita de Ciências da Saúde Albert Einstein, São Paulo, Brazil
| | - Fernanda Mansur
- Center for Experimental Research, Hospital Israelita Albert Einstein, São Paulo, Brazil
| | - André Luiz Teles E Silva
- Center for Experimental Research, Hospital Israelita Albert Einstein, São Paulo, Brazil.,Department of Genetics and Evolutionary Biology, University of São Paulo, São Paulo, Brazil
| | - Vitor Abreu de Goes
- Center for Experimental Research, Hospital Israelita Albert Einstein, São Paulo, Brazil.,School of Medicine, Faculdade Israelita de Ciências da Saúde Albert Einstein, São Paulo, Brazil
| | - Orly Reiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Andréa Laurato Sertié
- Center for Experimental Research, Hospital Israelita Albert Einstein, São Paulo, Brazil
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10
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Kaboodvand N, van den Heuvel MP, Fransson P. Adaptive frequency-based modeling of whole-brain oscillations: Predicting regional vulnerability and hazardousness rates. Netw Neurosci 2019; 3:1094-1120. [PMID: 31637340 PMCID: PMC6779267 DOI: 10.1162/netn_a_00104] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 07/24/2019] [Indexed: 11/25/2022] Open
Abstract
Whole-brain computational modeling based on structural connectivity has shown great promise in successfully simulating fMRI BOLD signals with temporal coactivation patterns that are highly similar to empirical functional connectivity patterns during resting state. Importantly, previous studies have shown that spontaneous fluctuations in coactivation patterns of distributed brain regions have an inherent dynamic nature with regard to the frequency spectrum of intrinsic brain oscillations. In this modeling study, we introduced frequency dynamics into a system of coupled oscillators, where each oscillator represents the local mean-field model of a brain region. We first showed that the collective behavior of interacting oscillators reproduces previously shown features of brain dynamics. Second, we examined the effect of simulated lesions in gray matter by applying an in silico perturbation protocol to the brain model. We present a new approach to map the effects of vulnerability in brain networks and introduce a measure of regional hazardousness based on mapping of the degree of divergence in a feature space.
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Affiliation(s)
- Neda Kaboodvand
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Martijn P. van den Heuvel
- Dutch Connectome Lab, Department of Complex Traits Genetics, Center for Neurogenomics and Cognitive Research, VU Amsterdam, Amsterdam, The Netherlands
- Department of Clinical Genetics, VU University Medical Center, Amsterdam Neuroscience, Amsterdam, 1081 HV, The Netherlands
| | - Peter Fransson
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
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11
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Bouyeure A, Germanaud D, Bekha D, Delattre V, Lefèvre J, Pinabiaux C, Mangin JF, Rivière D, Fischer C, Chiron C, Hertz-Pannier L, Noulhiane M. Three-Dimensional Probabilistic Maps of Mesial Temporal Lobe Structures in Children and Adolescents' Brains. Front Neuroanat 2018; 12:98. [PMID: 30498435 PMCID: PMC6249374 DOI: 10.3389/fnana.2018.00098] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 10/29/2018] [Indexed: 11/13/2022] Open
Abstract
The hippocampus and the adjacent perirhinal, entorhinal, temporopolar, and parahippocampal cortices are interconnected in a hierarchical MTL system crucial for memory processes. A probabilistic description of the anatomical location and spatial variability of MTL cortices in the child and adolescent brain would help to assess structure-function relationships. The rhinal sulcus (RS) and the collateral sulcus (CS) that border MTL cortices and influence their morphology have never been described in these populations. In this study, we identified the aforementioned structures on magnetic resonance images of 38 healthy subjects aged 7-17 years old. Relative to sulcal morphometry in the MTL, we showed RS-CS conformation is an additional factor of variability in the MTL that is not explained by other variables such as age, sex and brain volume; with an innovative method using permutation testing of the extrema of structures of interest, we showed that RS-SC conformation was not associated with differences of location of MTL sulci. Relative to probabilistic maps, we offered for the first time a systematic mapping of MTL structures in children and adolescent, mapping all the structures of the MTL system while taking sulcal morphology into account. Our results, with the probabilistic maps described here being freely available for download, will help to understand the anatomy of this region and help functional and clinical studies to accurately test structure-function hypotheses in the MTL during development. Free access to MTL pediatric atlas: http://neurovault.org/collections/2381/.
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Affiliation(s)
- Antoine Bouyeure
- INSERM, CEA, Université Paris Descartes, Sorbonne Paris Cité, Neurospin, UNIACT, UMR1129, Gif-sur-Yvette, France
| | - David Germanaud
- INSERM, CEA, Université Paris Descartes, Sorbonne Paris Cité, Neurospin, UNIACT, UMR1129, Gif-sur-Yvette, France
- Université Paris Diderot, Sorbonne Paris Cité, AP-HP, Hôpital Robert-Debré, DHU Protect, Service de Neurologie Pédiatrique et des Maladies Métaboliques, Paris, France
| | - Dhaif Bekha
- INSERM, CEA, Université Paris Descartes, Sorbonne Paris Cité, Neurospin, UNIACT, UMR1129, Gif-sur-Yvette, France
| | - Victor Delattre
- INSERM, CEA, Université Paris Descartes, Sorbonne Paris Cité, Neurospin, UNIACT, UMR1129, Gif-sur-Yvette, France
| | - Julien Lefèvre
- CNRS, ENSAM, LSIS UMR 7296, Aix Marseille University, Toulon University, Toulon, France
| | - Charlotte Pinabiaux
- Université Paris Ouest Nanterre La Défense, Laboratoire CHArt (EA 4004), Nanterre, France
| | | | - Denis Rivière
- CEA, University Paris Saclay, NeuroSpin, UNATI, Gif-sur-Yvette, France
| | - Clara Fischer
- CEA, University Paris Saclay, NeuroSpin, UNATI, Gif-sur-Yvette, France
| | - Catherine Chiron
- INSERM, CEA, Université Paris Descartes, Sorbonne Paris Cité, Neurospin, UNIACT, UMR1129, Gif-sur-Yvette, France
| | - Lucie Hertz-Pannier
- INSERM, CEA, Université Paris Descartes, Sorbonne Paris Cité, Neurospin, UNIACT, UMR1129, Gif-sur-Yvette, France
| | - Marion Noulhiane
- INSERM, CEA, Université Paris Descartes, Sorbonne Paris Cité, Neurospin, UNIACT, UMR1129, Gif-sur-Yvette, France
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12
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Narla ST, Decker B, Sarder P, Stachowiak EK, Stachowiak MK. Induced Pluripotent Stem Cells Reveal Common Neurodevelopmental Genome Deprograming in Schizophrenia. Results Probl Cell Differ 2018; 66:137-162. [PMID: 30209658 DOI: 10.1007/978-3-319-93485-3_6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Schizophrenia is a neurodevelopmental disorder characterized by complex aberrations in the structure, wiring, and chemistry of multiple neuronal systems. The abnormal developmental trajectory of the brain is established during gestation, long before clinical manifestation of the disease. Over 200 genes and even greater numbers of single nucleotide polymorphisms and copy number variations have been linked with schizophrenia. How does altered function of such a variety of genes lead to schizophrenia? We propose that the protein products of these altered genes converge on a common neurodevelopmental pathway responsible for the development of brain neural circuit and neurotransmitter systems. The results of a multichanneled investigation using induced pluripotent stem cell (iPSCs)- and embryonic stem cell (ESCs)-derived neuronal committed cells (NCCs) indicate an early (preneuronal) developmental-genomic etiology of schizophrenia and that the dysregulated developmental gene networks are common to genetically unrelated cases of schizophrenia. The results support a "watershed" mechanism in which mutations within diverse signaling pathways affect the common pan-ontogenic mechanism, integrative nuclear (n)FGFR1 signaling (INFS). Dysregulation of INFS in schizophrenia NCCs deconstructs coordinated gene networks and leads to formation of new networks by the dysregulated genes. This genome deprograming affects critical gene programs and pathways for neural development and functions. Studies show that the genomic deprograming reflect an altered nFGFR1-genome interactions and deregulation of miRNA genes by nFGFR1. In addition, changes in chromatin topology imposed by nFGFR1 may play a role in coordinate gene dysregulation in schizophrenia.
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Affiliation(s)
- Sridhar T Narla
- Department of Pathology and Anatomical Sciences, Molecular and Structural Neurobiology and Gene Therapy Program, State University of New York, Buffalo, NY, USA
| | - Brandon Decker
- Department of Pathology and Anatomical Sciences, Molecular and Structural Neurobiology and Gene Therapy Program, State University of New York, Buffalo, NY, USA
| | - Pinaki Sarder
- Department of Pathology and Anatomical Sciences, Molecular and Structural Neurobiology and Gene Therapy Program, State University of New York, Buffalo, NY, USA.,Department of Biomedical Engineering, State University of New York, Buffalo, NY, USA
| | - Ewa K Stachowiak
- Department of Pathology and Anatomical Sciences, Molecular and Structural Neurobiology and Gene Therapy Program, State University of New York, Buffalo, NY, USA.,Western New York Stem Cells Culture and Analysis Center, State University of New York, Buffalo, NY, USA
| | - Michal K Stachowiak
- Department of Pathology and Anatomical Sciences, Molecular and Structural Neurobiology and Gene Therapy Program, State University of New York, Buffalo, NY, USA. .,Department of Biomedical Engineering, State University of New York, Buffalo, NY, USA. .,Western New York Stem Cells Culture and Analysis Center, State University of New York, Buffalo, NY, USA.
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13
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Brain Organoids: Expanding Our Understanding of Human Development and Disease. Results Probl Cell Differ 2018; 66:183-206. [PMID: 30209660 DOI: 10.1007/978-3-319-93485-3_8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Stem cell-derived brain organoids replicate important stages of the prenatal human brain development and combined with the induced pluripotent stem cell (iPSC) technology offer an unprecedented model for investigating human neurological diseases including autism and microcephaly. We describe the history and birth of organoids and their application, focusing on cerebral organoids derived from embryonic stem cells and iPSCs. We discuss new insights into organoid-based model of schizophrenia and shed light on challenges and future applications of organoid-based disease model system. This review also suggests hitherto unrevealed potential applications of organoids in combining with new technologies such as nanophotonics/optogenomics for controlling brain development and atomic force microscopy for studying mechanical forces that shape the developing brain.
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14
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Purinergic system in psychiatric diseases. Mol Psychiatry 2018; 23:94-106. [PMID: 28948971 DOI: 10.1038/mp.2017.188] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 07/15/2017] [Accepted: 07/20/2017] [Indexed: 12/14/2022]
Abstract
Psychiatric disorders are debilitating diseases, affecting >80 million people worldwide. There are no causal cures for psychiatric disorders and available therapies only treat the symptoms. The etiology of psychiatric disorders is unknown, although it has been speculated to be a combination of environmental, stress and genetic factors. One of the neurotransmitter systems implicated in the biology of psychiatric disorders is the purinergic system. In this review, we performed a comprehensive search of the literature about the role and function of the purinergic system in the development and predisposition to psychiatric disorders, with a focus on depression, schizophrenia, bipolar disorder, autism, anxiety and attention deficit/hyperactivity disorder. We also describe how therapeutics used for psychiatric disorders act on the purinergic system.
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15
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Stachowiak EK, Benson CA, Narla ST, Dimitri A, Chuye LEB, Dhiman S, Harikrishnan K, Elahi S, Freedman D, Brennand KJ, Sarder P, Stachowiak MK. Cerebral organoids reveal early cortical maldevelopment in schizophrenia-computational anatomy and genomics, role of FGFR1. Transl Psychiatry 2017; 7:6. [PMID: 30446636 PMCID: PMC5802550 DOI: 10.1038/s41398-017-0054-x] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 08/17/2017] [Accepted: 09/23/2017] [Indexed: 12/15/2022] Open
Abstract
Studies of induced pluripotent stem cells (iPSCs) from schizophrenia patients and control individuals revealed that the disorder is programmed at the preneuronal stage, involves a common dysregulated mRNA transcriptome, and identified Integrative Nuclear FGFR1 Signaling a common dysregulated mechanism. We used human embryonic stem cell (hESC) and iPSC-derived cerebral organoids from four controls and three schizophrenia patients to model the first trimester of in utero brain development. The schizophrenia organoids revealed an abnormal scattering of proliferating Ki67+ neural progenitor cells (NPCs) from the ventricular zone (VZ), throughout the intermediate (IZ) and cortical (CZ) zones. TBR1 pioneer neurons and reelin, which guides cortico-petal migration, were restricted from the schizophrenia cortex. The maturing neurons were abundantly developed in the subcortical regions, but were depleted from the schizophrenia cortex. The decreased intracortical connectivity was denoted by changes in the orientation and morphology of calretinin interneurons. In schizophrenia organoids, nuclear (n)FGFR1 was abundantly expressed by developing subcortical cells, but was depleted from the neuronal committed cells (NCCs) of the CZ. Transfection of dominant negative and constitutively active nFGFR1 caused widespread disruption of the neuro-ontogenic gene networks in hESC-derived NPCs and NCCs. The fgfr1 gene was the most prominent FGFR gene expressed in NPCs and NCCs, and blocking with PD173074 reproduced both the loss of nFGFR1 and cortical neuronal maturation in hESC cerebral organoids. We report for the first time, progression of the cortical malformation in schizophrenia and link it to altered FGFR1 signaling. Targeting INFS may offer a preventive treatment of schizophrenia.
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Affiliation(s)
- E. K. Stachowiak
- 0000 0004 1936 9887grid.273335.3Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY USA
| | - C. A. Benson
- 0000 0004 1936 9887grid.273335.3Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY USA
| | - S. T. Narla
- 0000 0004 1936 9887grid.273335.3Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY USA
| | - A. Dimitri
- 0000 0004 1936 9887grid.273335.3Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY USA ,0000 0004 0388 0154grid.264268.cDepartment of Biology, State University of New York at Fredonia, Fredonia, NY USA
| | - L. E. Bayona Chuye
- 0000 0004 1936 9887grid.273335.3Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY USA
| | - S. Dhiman
- 0000 0004 1936 9887grid.273335.3Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY USA ,0000 0004 1936 9887grid.273335.3Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY USA
| | - K. Harikrishnan
- 0000 0004 1936 9887grid.273335.3Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY USA ,0000 0004 1936 9887grid.273335.3Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY USA
| | - S. Elahi
- 0000 0004 1936 9887grid.273335.3Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY USA
| | - D. Freedman
- 0000 0004 1936 9887grid.273335.3Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY USA
| | - K. J. Brennand
- Icahn School of Medicine at Mount Sinai, Departments of Psychiatry and Neuroscience, New York, NY USA
| | - P. Sarder
- 0000 0004 1936 9887grid.273335.3Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY USA ,0000 0004 1936 9887grid.273335.3Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY USA
| | - M. K. Stachowiak
- 0000 0004 1936 9887grid.273335.3Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY USA ,0000 0004 1936 9887grid.273335.3Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY USA
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16
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Narla ST, Lee YW, Benson C, Sarder P, Brennand K, Stachowiak E, Stachowiak M. Common developmental genome deprogramming in schizophrenia - Role of Integrative Nuclear FGFR1 Signaling (INFS). Schizophr Res 2017; 185:17-32. [PMID: 28094170 PMCID: PMC5507209 DOI: 10.1016/j.schres.2016.12.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 12/06/2016] [Accepted: 12/12/2016] [Indexed: 12/16/2022]
Abstract
The watershed-hypothesis of schizophrenia asserts that over 200 different mutations dysregulate distinct pathways that converge on an unspecified common mechanism(s) that controls disease ontogeny. Consistent with this hypothesis, our RNA-sequencing of neuron committed cells (NCCs) differentiated from established iPSCs of 4 schizophrenia patients and 4 control subjects uncovered a dysregulated transcriptome of 1349 mRNAs common to all patients. Data reveals a global dysregulation of developmental genome, deconstruction of coordinated mRNA networks, and the formation of aberrant, new coordinated mRNA networks indicating a concerted action of the responsible factor(s). Sequencing of miRNA transcriptomes demonstrated an overexpression of 16 miRNAs and deconstruction of interactive miRNA-mRNA networks in schizophrenia NCCs. ChiPseq revealed that the nuclear (n) form of FGFR1, a pan-ontogenic regulator, is overexpressed in schizophrenia NCCs and overtargets dysregulated mRNA and miRNA genes. The nFGFR1 targeted 54% of all human gene promoters and 84.4% of schizophrenia dysregulated genes. The upregulated genes reside within major developmental pathways that control neurogenesis and neuron formation, whereas downregulated genes are involved in oligodendrogenesis. Our results indicate (i) an early (preneuronal) genomic etiology of schizophrenia, (ii) dysregulated genes and new coordinated gene networks are common to unrelated cases of schizophrenia, (iii) gene dysregulations are accompanied by increased nFGFR1-genome interactions, and (iv) modeling of increased nFGFR1 by an overexpression of a nFGFR1 lead to up or downregulation of selected genes as observed in schizophrenia NCCs. Together our results designate nFGFR1 signaling as a potential common dysregulated mechanism in investigated patients and potential therapeutic target in schizophrenia.
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Affiliation(s)
- S. T. Narla
- Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY, USA,Western New York Stem Cell Culture and Analysis Center, State University of New York at Buffalo, Buffalo, NY, USA
| | - Y-W. Lee
- Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - C.A. Benson
- Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY, USA,Western New York Stem Cell Culture and Analysis Center, State University of New York at Buffalo, Buffalo, NY, USA
| | - P. Sarder
- Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - K. Brennand
- Icahn School of Medicine at Mount Sinai, Departments of Psychiatry and Neuroscience, New York, NY, USA
| | - E.K. Stachowiak
- Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY, USA,Western New York Stem Cell Culture and Analysis Center, State University of New York at Buffalo, Buffalo, NY, USA
| | - M.K. Stachowiak
- Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY, USA,Western New York Stem Cell Culture and Analysis Center, State University of New York at Buffalo, Buffalo, NY, USA,Correspondence should be addressed to Michal K. Stachowiak Department of Pathology and Anatomical Sciences, SUNY, 3435 Main Street, 206A Farber Hall, Buffalo, N.Y. 14214, tel. (716) 829 3540
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17
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Koga M, Serritella AV, Sawa A, Sedlak TW. Implications for reactive oxygen species in schizophrenia pathogenesis. Schizophr Res 2016; 176:52-71. [PMID: 26589391 DOI: 10.1016/j.schres.2015.06.022] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 06/20/2015] [Accepted: 06/23/2015] [Indexed: 12/18/2022]
Abstract
Oxidative stress is a well-recognized participant in the pathophysiology of multiple brain disorders, particularly neurodegenerative conditions such as Alzheimer's and Parkinson's diseases. While not a dementia, a wide body of evidence has also been accumulating for aberrant reactive oxygen species and inflammation in schizophrenia. Here we highlight roles for oxidative stress as a common mechanism by which varied genetic and epidemiologic risk factors impact upon neurodevelopmental processes that underlie the schizophrenia syndrome. While there is longstanding evidence that schizophrenia may not have a single causative lesion, a common pathway involving oxidative stress opens the possibility for intervention at susceptible phases.
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Affiliation(s)
- Minori Koga
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Meyer 3-166, Baltimore, MD 21287, USA
| | - Anthony V Serritella
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Meyer 3-166, Baltimore, MD 21287, USA
| | - Akira Sawa
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Meyer 3-166, Baltimore, MD 21287, USA
| | - Thomas W Sedlak
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Meyer 3-166, Baltimore, MD 21287, USA.
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18
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O'Connor WT, O'Shea SD. Clozapine and GABA transmission in schizophrenia disease models. Pharmacol Ther 2015; 150:47-80. [DOI: 10.1016/j.pharmthera.2015.01.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 01/06/2015] [Indexed: 11/30/2022]
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19
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Pyramidal cell selective ablation of N-methyl-D-aspartate receptor 1 causes increase in cellular and network excitability. Biol Psychiatry 2015; 77:556-68. [PMID: 25156700 PMCID: PMC4297754 DOI: 10.1016/j.biopsych.2014.06.026] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 06/05/2014] [Accepted: 06/22/2014] [Indexed: 12/15/2022]
Abstract
BACKGROUND Neuronal activity at gamma frequency is impaired in schizophrenia (SZ) and is considered critical for cognitive performance. Such impairments are thought to be due to reduced N-methyl-D-aspartate receptor (NMDAR)-mediated inhibition from parvalbumin interneurons, rather than a direct role of impaired NMDAR signaling on pyramidal neurons. However, recent studies suggest a direct role of pyramidal neurons in regulating gamma oscillations. In particular, a computational model has been proposed in which phasic currents from pyramidal cells could drive synchronized feedback inhibition from interneurons. As such, impairments in pyramidal neuron activity could lead to abnormal gamma oscillations. However, this computational model has not been tested experimentally and the molecular mechanisms underlying pyramidal neuron dysfunction in SZ remain unclear. METHODS In the present study, we tested the hypothesis that SZ-related phenotypes could arise from reduced NMDAR signaling in pyramidal neurons using forebrain pyramidal neuron specific NMDA receptor 1 knockout mice. RESULTS The mice displayed increased baseline gamma power, as well as sociocognitive impairments. These phenotypes were associated with increased pyramidal cell excitability due to changes in inherent membrane properties. Interestingly, mutant mice showed decreased expression of GIRK2 channels, which has been linked to increased neuronal excitability. CONCLUSIONS Our data demonstrate for the first time that NMDAR hypofunction in pyramidal cells is sufficient to cause electrophysiological, molecular, neuropathological, and behavioral changes related to SZ.
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20
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Muraki K, Tanigaki K. Neuronal migration abnormalities and its possible implications for schizophrenia. Front Neurosci 2015; 9:74. [PMID: 25805966 PMCID: PMC4354421 DOI: 10.3389/fnins.2015.00074] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 02/20/2015] [Indexed: 02/01/2023] Open
Abstract
Schizophrenia is a complex mental disorder that displays behavioral deficits such as decreased sensory gating, reduced social interaction and working memory deficits. The neurodevelopmental model is one of the widely accepted hypotheses of the etiology of schizophrenia. Subtle developmental abnormalities of the brain which stated long before the onset of clinical symptoms are thought to lead to the emergence of illness. Schizophrenia has strong genetic components but its underlying molecular pathogenesis is still poorly understood. Genetic linkage and association studies have identified several genes involved in neuronal migrations as candidate susceptibility genes for schizophrenia, although their effect size is small. Recent progress in copy number variation studies also has identified much higher risk loci such as 22q11. Based on these genetic findings, we are now able to utilize genetically-defined animal models. Here we summarize the results of neurodevelopmental and behavioral analysis of genetically-defined animal models. Furthermore, animal model experiments have demonstrated that embryonic and perinatal neurodevelopmental insults in neurogenesis and neuronal migrations cause neuronal functional and behavioral deficits in affected adult animals, which are similar to those of schizophrenic patients. However, these findings do not establish causative relationship. Genetically-defined animal models are a critical approach to explore the relationship between neuronal migration abnormalities and behavioral abnormalities relevant to schizophrenia.
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Affiliation(s)
- Kazue Muraki
- Shiga Medical Center, Research Institute Moriyama, Shiga, Japan
| | - Kenji Tanigaki
- Shiga Medical Center, Research Institute Moriyama, Shiga, Japan
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21
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Ramsden HL, Sürmeli G, McDonagh SG, Nolan MF. Laminar and dorsoventral molecular organization of the medial entorhinal cortex revealed by large-scale anatomical analysis of gene expression. PLoS Comput Biol 2015; 11:e1004032. [PMID: 25615592 PMCID: PMC4304787 DOI: 10.1371/journal.pcbi.1004032] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 11/10/2014] [Indexed: 12/14/2022] Open
Abstract
Neural circuits in the medial entorhinal cortex (MEC) encode an animal's position and orientation in space. Within the MEC spatial representations, including grid and directional firing fields, have a laminar and dorsoventral organization that corresponds to a similar topography of neuronal connectivity and cellular properties. Yet, in part due to the challenges of integrating anatomical data at the resolution of cortical layers and borders, we know little about the molecular components underlying this organization. To address this we develop a new computational pipeline for high-throughput analysis and comparison of in situ hybridization (ISH) images at laminar resolution. We apply this pipeline to ISH data for over 16,000 genes in the Allen Brain Atlas and validate our analysis with RNA sequencing of MEC tissue from adult mice. We find that differential gene expression delineates the borders of the MEC with neighboring brain structures and reveals its laminar and dorsoventral organization. We propose a new molecular basis for distinguishing the deep layers of the MEC and show that their similarity to corresponding layers of neocortex is greater than that of superficial layers. Our analysis identifies ion channel-, cell adhesion- and synapse-related genes as candidates for functional differentiation of MEC layers and for encoding of spatial information at different scales along the dorsoventral axis of the MEC. We also reveal laminar organization of genes related to disease pathology and suggest that a high metabolic demand predisposes layer II to neurodegenerative pathology. In principle, our computational pipeline can be applied to high-throughput analysis of many forms of neuroanatomical data. Our results support the hypothesis that differences in gene expression contribute to functional specialization of superficial layers of the MEC and dorsoventral organization of the scale of spatial representations.
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Affiliation(s)
- Helen L. Ramsden
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, United Kingdom
- Neuroinformatics Doctoral Training Centre, School of Informatics, University of Edinburgh, Edinburgh, United Kingdom
| | - Gülşen Sürmeli
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, United Kingdom
| | - Steven G. McDonagh
- Institute of Perception, Action and Behaviour, School of Informatics, University of Edinburgh, Edinburgh, United Kingdom
| | - Matthew F. Nolan
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Brain Development and Repair, inStem, Bangalore, India
- * E-mail:
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22
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Alteration of imprinted Dlk1-Dio3 miRNA cluster expression in the entorhinal cortex induced by maternal immune activation and adolescent cannabinoid exposure. Transl Psychiatry 2014; 4:e452. [PMID: 25268256 PMCID: PMC4203021 DOI: 10.1038/tp.2014.99] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 07/09/2014] [Accepted: 08/21/2014] [Indexed: 12/19/2022] Open
Abstract
A significant feature of the cortical neuropathology of schizophrenia is a disturbance in the biogenesis of short non-coding microRNA (miRNA) that regulate translation and stability of mRNA. While the biological origin of this phenomenon has not been defined, it is plausible that it relates to major environmental risk factors associated with the disorder such as exposure to maternal immune activation (MIA) and adolescent cannabis use. To explore this hypothesis, we administered the viral mimic poly I:C to pregnant rats and further exposed some of their maturing offsprings to daily injections of the synthetic cannabinoid HU210 for 14 days starting on postnatal day 35. Whole-genome miRNA expression analysis was then performed on the left and right hemispheres of the entorhinal cortex (EC), a region strongly associated with schizophrenia. Animals exposed to either treatment alone or in combination exhibited significant differences in the expression of miRNA in the left hemisphere, whereas the right hemisphere was less responsive. Hemisphere-associated differences in miRNA expression were greatest in the combined treatment and highly over-represented in a single imprinted locus on chromosome 6q32. This observation was significant as the syntenic 14q32 locus in humans encodes a large proportion of miRNAs differentially expressed in peripheral blood lymphocytes from patients with schizophrenia, suggesting that interaction of early and late environmental insults may affect miRNA expression, in a manner that is relevant to schizophrenia.
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23
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Catts VS, Fung SJ, Long LE, Joshi D, Vercammen A, Allen KM, Fillman SG, Rothmond DA, Sinclair D, Tiwari Y, Tsai SY, Weickert TW, Shannon Weickert C. Rethinking schizophrenia in the context of normal neurodevelopment. Front Cell Neurosci 2013; 7:60. [PMID: 23720610 PMCID: PMC3654207 DOI: 10.3389/fncel.2013.00060] [Citation(s) in RCA: 144] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 04/16/2013] [Indexed: 01/11/2023] Open
Abstract
The schizophrenia brain is differentiated from the normal brain by subtle changes, with significant overlap in measures between normal and disease states. For the past 25 years, schizophrenia has increasingly been considered a neurodevelopmental disorder. This frame of reference challenges biological researchers to consider how pathological changes identified in adult brain tissue can be accounted for by aberrant developmental processes occurring during fetal, childhood, or adolescent periods. To place schizophrenia neuropathology in a neurodevelopmental context requires solid, scrutinized evidence of changes occurring during normal development of the human brain, particularly in the cortex; however, too often data on normative developmental change are selectively referenced. This paper focuses on the development of the prefrontal cortex and charts major molecular, cellular, and behavioral events on a similar time line. We first consider the time at which human cognitive abilities such as selective attention, working memory, and inhibitory control mature, emphasizing that attainment of full adult potential is a process requiring decades. We review the timing of neurogenesis, neuronal migration, white matter changes (myelination), and synapse development. We consider how molecular changes in neurotransmitter signaling pathways are altered throughout life and how they may be concomitant with cellular and cognitive changes. We end with a consideration of how the response to drugs of abuse changes with age. We conclude that the concepts around the timing of cortical neuronal migration, interneuron maturation, and synaptic regression in humans may need revision and include greater emphasis on the protracted and dynamic changes occurring in adolescence. Updating our current understanding of post-natal neurodevelopment should aid researchers in interpreting gray matter changes and derailed neurodevelopmental processes that could underlie emergence of psychosis.
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Affiliation(s)
- Vibeke S. Catts
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Samantha J. Fung
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Leonora E. Long
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Medical Sciences, University of New South WalesSydney, NSW, Australia
| | - Dipesh Joshi
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Ans Vercammen
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
- School of Psychology, Australian Catholic UniversitySydney, NSW, Australia
| | - Katherine M. Allen
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Stu G. Fillman
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Debora A. Rothmond
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
| | - Duncan Sinclair
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Yash Tiwari
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Medical Sciences, University of New South WalesSydney, NSW, Australia
| | - Shan-Yuan Tsai
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Thomas W. Weickert
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Cynthia Shannon Weickert
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
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24
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Greco CM, Navarro CS, Hunsaker MR, Maezawa I, Shuler JF, Tassone F, Delany M, Au JW, Berman RF, Jin LW, Schumann C, Hagerman PJ, Hagerman RJ. Neuropathologic features in the hippocampus and cerebellum of three older men with fragile X syndrome. Mol Autism 2011; 2:2. [PMID: 21303513 PMCID: PMC3045897 DOI: 10.1186/2040-2392-2-2] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2010] [Accepted: 02/08/2011] [Indexed: 12/22/2022] Open
Abstract
Background Fragile X syndrome (FXS) is the most common inherited form of intellectual disability, and is the most common single-gene disorder known to be associated with autism. Despite recent advances in functional neuroimaging and our understanding of the molecular pathogenesis, only limited neuropathologic information on FXS is available. Methods Neuropathologic examinations were performed on post-mortem brain tissue from three older men (aged 57, 64 and 78 years) who had received a clinical or genetic diagnosis of FXS. In each case, physical and cognitive features were typical of FXS, and one man was also diagnosed with autism. Guided by reports of clinical and neuroimaging abnormalities of the limbic system and cerebellum of individuals with FXS, the current analysis focused on neuropathologic features present in the hippocampus and the cerebellar vermis. Results Histologic and immunologic staining revealed abnormalities in both the hippocampus and cerebellar vermis. Focal thickening of hippocampal CA1 and irregularities in the appearance of the dentate gyrus were identified. All lobules of the cerebellar vermis and the lateral cortex of the posterior lobe of the cerebellum had decreased numbers of Purkinje cells, which were occasionally misplaced, and often lacked proper orientation. There were mild, albeit excessive, undulations of the internal granular cell layer, with patchy foliar white matter axonal and astrocytic abnormalities. Quantitative analysis documented panfoliar atrophy of both the anterior and posterior lobes of the vermis, with preferential atrophy of the posterior lobule (VI to VII) compared with age-matched normal controls. Conclusions Significant morphologic changes in the hippocampus and cerebellum in three adult men with FXS were identified. This pattern of pathologic features supports the idea that primary defects in neuronal migration, neurogenesis and aging may underlie the neuropathology reported in FXS.
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Affiliation(s)
- Claudia M Greco
- MIND Institute, University of California-Davis Medical Center, Sacramento, CA, USA.
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Coleman MJ, Titone D, Krastoshevsky O, Krause V, Huang Z, Mendell NR, Eichenbaum H, Levy DL. Reinforcement ambiguity and novelty do not account for transitive inference deficits in schizophrenia. Schizophr Bull 2010; 36:1187-200. [PMID: 19460878 PMCID: PMC2963057 DOI: 10.1093/schbul/sbp039] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The capacity for transitive inference (TI), a form of relational memory organization, is impaired in schizophrenia patients. In order to disambiguate deficits in TI from the effects of ambiguous reinforcement history and novelty, 28 schizophrenia and 20 nonpsychiatric control subjects were tested on newly developed TI and non-TI tasks that were matched on these 2 variables. Schizophrenia patients performed significantly worse than controls on the TI task but were able to make equivalently difficult nontransitive judgments as well as controls. Neither novelty nor reinforcement ambiguity accounted for the selective deficit of the patients on the TI task. These findings implicate a disturbance in relational memory organization, likely subserved by hippocampal dysfunction, in the pathophysiology of schizophrenia.
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Affiliation(s)
| | - Debra Titone
- Department of Psychology, McGill University, Montreal, Quebec, Canada
| | | | - Verena Krause
- Psychology Research Laboratory, McLean Hospital, Belmont, MA 02478
| | - Zhuying Huang
- Department of Applied Mathematics and Statistics, Stony Brook University, Stony Brook, NY
| | - Nancy R. Mendell
- Department of Applied Mathematics and Statistics, Stony Brook University, Stony Brook, NY
| | | | - Deborah L. Levy
- Psychology Research Laboratory, McLean Hospital, Belmont, MA 02478,To whom correspondence should be addressed; tel: 617-855-2854, fax: 617-855-2778, e-mail:
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26
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White matter neuron alterations in schizophrenia and related disorders. Int J Dev Neurosci 2010; 29:325-34. [PMID: 20691252 DOI: 10.1016/j.ijdevneu.2010.07.236] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Revised: 07/23/2010] [Accepted: 07/26/2010] [Indexed: 12/15/2022] Open
Abstract
Increased density and altered spatial distribution of subcortical white matter neurons (WMNs) represents one of the more well replicated cellular alterations found in schizophrenia and related disease. In many of the affected cases, the underlying genetic risk architecture for these WMN abnormalities remains unknown. Increased density of neurons immunoreactive for Microtubule-Associated Protein 2 (MAP2) and Neuronal Nuclear Antigen (NeuN) have been reported by independent studies, though there are negative reports as well; additionally, group differences in some of the studies appear to be driven by a small subset of cases. Alterations in markers for inhibitory (GABAergic) neurons have also been described. For example, downregulation of neuropeptide Y (NPY) and nitric oxide synthase (NOS1) in inhibitory WMN positioned at the gray/white matter border, as well as altered spatial distribution, have been reported. While increased density of WMN has been suggested to reflect disturbance of neurodevelopmental processes, including neuronal migration, neurogenesis, and cell death, alternative hypotheses--such as an adaptive response to microglial activation in mature CNS, as has been described in multiple sclerosis--should also be considered. We argue that larger scale studies involving hundreds of postmortem specimens will be necessary in order to clearly establish the subset of subjects affected. Additionally, these larger cohorts could make it feasible to connect the cellular pathology to environmental and genetic factors implicated in schizophrenia, bipolar disorder, and autism. These could include the 22q11 deletion (Velocardiofacial/DiGeorge) syndrome, which in some cases is associated with neuronal ectopias in white matter.
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Abstract
In the etymology of schizophrenia, the genetic component seems to play an essential role. Studies have shown more than 130 genes of susceptibility for schizophrenia: the majority of these studies, however, has yet to be confirmed- they are searching for more definition on the relevant functions of the genetic variation of schizophrenia. Recent studies suggest that a cluster of candidate genes in the interconnected network pathways are implicated in transmission of the glutamate the plasticity of the synapses, in oxidative stress, myelination and the profitability of oligodendrocytes. Previous neuropathological studies on schizophrenia did not identify specific neurodegenerative characteristics of this disease. Scientific evidence suggests that the physiopathology of schizophrenia involves alterations of the intracellular transmission pathway, those which are associated with reduced cerebral volume in some structures of white and gray matter. In particular, in schizophrenia, a reduction of medium cerebral volume has been observed, as has a reduction of the cortical regional volumes with reference to the frontal, temporal, and parietal areas of the brain - this is all in addition to a reduction of the prefrontal cortex, hippocampus, amygdala, thalamus, and the cerebellum. The cytoarchitectonic alterations in schizophrenia may be an expression of the pathology's processing, as are axonal damage and loss, reduction of myelination, and loss of neuropil. These all contribute to the reduction of the volume of the cerebral parenchima, and the corresponding augmentation of the cerebral spinal fluid. The inheritance of schizophrenia may appear high/elevated, but not a certain eventuality. In analysis of subtype specifics. However, this statistics remains significant in all studies. The role of the environmental factors in the development of schizophrenia is highlighted by studies which have been conducted on monozygotic patients affected by schizophrenia. While their genetic code is 100% similar, that is to say, entirely identical, one of the pair can be diagnosed as schizophrenic, while the other of the monozygotic pair has the 50% of the possibility not to contract schizophrenia. It is well known that genetic and environmental factors influence multiple aspects of human behavior, they can increase the susceptibility towards a mental disturbance. The reciprocal effects of these factors are placed in two distinct and diverse categories: gene environment interaction, which expresses the terminal genetic variations of susceptibility to environmental risk, and environmental gene correlations, where the genetic variability can increase or reduce the likelihood of the exposure to environmental determinant risk, includes early stressful events of life.
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Affiliation(s)
- C.M.V. Conti
- Department of Biomedical Science, Clinical Psychology Division, University of Chieti, Italy
| | - M. Fulcheri
- Department of Biomedical Science, Clinical Psychology Division, University of Chieti, Italy
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28
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Matricon J, Bellon A, Frieling H, Kebir O, Le Pen G, Beuvon F, Daumas-Duport C, Jay TM, Krebs MO. Neuropathological and Reelin deficiencies in the hippocampal formation of rats exposed to MAM; differences and similarities with schizophrenia. PLoS One 2010; 5:e10291. [PMID: 20421980 PMCID: PMC2858661 DOI: 10.1371/journal.pone.0010291] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Accepted: 03/15/2010] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Adult rats exposed to methylazoxymethanol (MAM) at embryonic day 17 (E17) consistently display behavioral characteristics similar to that observed in patients with schizophrenia and replicate neuropathological findings from the prefrontal cortex of psychotic individuals. However, a systematic neuropathological analysis of the hippocampal formation and the thalamus in these rats is lacking. It is also unclear if reelin, a protein consistently associated with schizophrenia and potentially involved in the mechanism of action of MAM, participates in the neuropathological effects of this compound. Therefore, a thorough assessment including cytoarchitectural and neuromorphometric measurements of eleven brain regions was conducted. Numbers of reelin positive cells and reelin expression and methylation levels were also studied. PRINCIPAL FINDINGS Compared to untreated rats, MAM-exposed animals showed a reduction in the volume of entorhinal cortex, hippocampus and mediodorsal thalamus associated with decreased neuronal soma. The entorhinal cortex also showed laminar disorganization and neuronal clusters. Reelin methylation in the hippocampus was decreased whereas reelin positive neurons and reelin expression were unchanged. CONCLUSIONS Our results indicate that E17-MAM exposure reproduces findings from the hippocampal formation and the mediodorsal thalamus of patients with schizophrenia while providing little support for reelin's involvement. Moreover, these results strongly suggest MAM-treated animals have a diminished neuropil, which likely arises from abnormal neurite formation; this supports a recently proposed pathophysiological hypothesis for schizophrenia.
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Affiliation(s)
- Julien Matricon
- INSERM U894, Laboratoire de Physiopathologie des Maladies Psychiatriques, Centre de Psychiatrie et Neurosciences, Paris, France
- Université Paris Descartes, Faculté de Médecine Paris Descartes, Hôpital Sainte-Anne, Paris, France
| | - Alfredo Bellon
- INSERM U894, Laboratoire de Physiopathologie des Maladies Psychiatriques, Centre de Psychiatrie et Neurosciences, Paris, France
- Université Paris Descartes, Faculté de Médecine Paris Descartes, Hôpital Sainte-Anne, Paris, France
- * E-mail: (AB); (MOK)
| | - Helge Frieling
- INSERM U894, Laboratoire de Physiopathologie des Maladies Psychiatriques, Centre de Psychiatrie et Neurosciences, Paris, France
- Department of Psychiatry, Socialpsychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany
| | - Oussama Kebir
- INSERM U894, Laboratoire de Physiopathologie des Maladies Psychiatriques, Centre de Psychiatrie et Neurosciences, Paris, France
- Université Paris Descartes, Faculté de Médecine Paris Descartes, Hôpital Sainte-Anne, Paris, France
| | - Gwenaëlle Le Pen
- INSERM U894, Laboratoire de Physiopathologie des Maladies Psychiatriques, Centre de Psychiatrie et Neurosciences, Paris, France
- Université Paris Descartes, Faculté de Médecine Paris Descartes, Hôpital Sainte-Anne, Paris, France
| | - Frédéric Beuvon
- Neuropathology unit, Université Paris Descartes, Faculté de Médecine Paris Descartes, Hôpital Sainte-Anne, Paris, France
- INSERM U894, Laboratoire de Plasticité gliale et tumeurs cérébrales, Centre de Psychiatrie et Neurosciences, Paris, France
| | - Catherine Daumas-Duport
- Neuropathology unit, Université Paris Descartes, Faculté de Médecine Paris Descartes, Hôpital Sainte-Anne, Paris, France
- INSERM U894, Laboratoire de Plasticité gliale et tumeurs cérébrales, Centre de Psychiatrie et Neurosciences, Paris, France
| | - Thérèse M. Jay
- INSERM U894, Laboratoire de Physiopathologie des Maladies Psychiatriques, Centre de Psychiatrie et Neurosciences, Paris, France
- Université Paris Descartes, Faculté de Médecine Paris Descartes, Hôpital Sainte-Anne, Paris, France
| | - Marie-Odile Krebs
- INSERM U894, Laboratoire de Physiopathologie des Maladies Psychiatriques, Centre de Psychiatrie et Neurosciences, Paris, France
- Université Paris Descartes, Faculté de Médecine Paris Descartes, Hôpital Sainte-Anne, Paris, France
- * E-mail: (AB); (MOK)
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Abstract
The neurodevelopmental hypothesis of schizophrenia asserts that the underlying pathology of schizophrenia has its roots in brain development and that these brain abnormalities do not manifest themselves until adolescence or early adulthood. Animal models based on developmental manipulations have provided insight into the vulnerability of the developing fetus and the importance of the early environment for normal maturation. These models have provided a wide range of validated approaches to answer questions regarding environmental influences on both neural and behavioral development. In an effort to better understand the developmental hypothesis of schizophrenia, animal models have been developed, which seek to model the etiology and/or the pathophysiology of schizophrenia or specific behaviors associated with the disease. Developmental models specific to schizophrenia have focused on epidemiological risk factors (e.g., prenatal viral insult, birth complications) or more heuristic models aimed at understanding the developmental neuropathology of the disease (e.g., ventral hippocampal lesions). The combined approach of behavioral and neuroanatomical evaluation of these models strengthens their utility in improving our understanding of the pathophysiology of schizophrenia and developing new treatment strategies.
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Affiliation(s)
- Susan B Powell
- University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0804, USA.
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30
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Association between myelin basic protein expression and left entorhinal cortex pre-alpha cell layer disorganization in schizophrenia. Brain Res 2009; 1301:126-34. [DOI: 10.1016/j.brainres.2009.09.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Revised: 09/02/2009] [Accepted: 09/03/2009] [Indexed: 11/19/2022]
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31
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Coutureau E, Di Scala G. Entorhinal cortex and cognition. Prog Neuropsychopharmacol Biol Psychiatry 2009; 33:753-61. [PMID: 19376185 DOI: 10.1016/j.pnpbp.2009.03.038] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2009] [Accepted: 03/30/2009] [Indexed: 10/20/2022]
Abstract
Understanding the function of the entorhinal cortex (EC) has been an important subject over the years, not least because of its cortical intermediary to and from the hippocampus proper, and because of electrophysiological advances which have started to reveal the physiology in behaving animals. Clearly, a lot more needs to be done but is clear to date that EC is not merely a throughput station providing all hippocampal subfields with sensory information, but that processing within EC contributes significantly to attention, conditioning, event and spatial cognition possibly by compressing representations that overlap in time. These are transmitted to the hippocampus, where they are differentiated again and returned to EC. Preliminary evidence for such a role, but also their possible pitfalls are summarised.
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Affiliation(s)
- Etienne Coutureau
- Centre de Neurosciences Intégratives et Cognitives, UMR 5228 CNRS, Universités de Bordeaux 1 & 2, Avenue des Facultés, 33405 Talence, France
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32
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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.
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Affiliation(s)
- J-P Olié
- Inserm U894, Center of Psychiatry and Neurosciences, Paris, France.
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33
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Fischl B, Stevens AA, Rajendran N, Yeo BTT, Greve DN, Van Leemput K, Polimeni JR, Kakunoori S, Buckner RL, Pacheco J, Salat DH, Melcher J, Frosch MP, Hyman BT, Grant PE, Rosen BR, van der Kouwe AJW, Wiggins GC, Wald LL, Augustinack JC. Predicting the location of entorhinal cortex from MRI. Neuroimage 2009; 47:8-17. [PMID: 19376238 DOI: 10.1016/j.neuroimage.2009.04.033] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2009] [Revised: 03/23/2009] [Accepted: 04/07/2009] [Indexed: 11/18/2022] Open
Abstract
Entorhinal cortex (EC) is a medial temporal lobe area critical to memory formation and spatial navigation that is among the earliest parts of the brain affected by Alzheimer's disease (AD). Accurate localization of EC would thus greatly facilitate early detection and diagnosis of AD. In this study, we used ultra-high resolution ex vivo MRI to directly visualize the architectonic features that define EC rostrocaudally and mediolaterally, then applied surface-based registration techniques to quantify the variability of EC with respect to cortical geometry, and made predictions of its location on in vivo scans. The results indicate that EC can be localized quite accurately based on cortical folding patterns, within 3 mm in vivo, a significant step forward in our ability to detect the earliest effects of AD when clinical intervention is most likely to be effective.
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Affiliation(s)
- Bruce Fischl
- Athinoula A Martinos Center, Department of Radiology, MGH, Harvard Medical School, Charlestown, MA 02129, USA.
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34
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Kalus P, Falkai P, Heinz A. [Structural and functional brain changes in schizophrenic disorders. Indications of early neuronal developmental disturbances?]. DER NERVENARZT 2008; 79:275-87. [PMID: 18264816 DOI: 10.1007/s00115-008-2414-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The neurodevelopmental hypothesis of schizophrenia, which was established 30 years ago and discussed controversially for a long time, postulates that pre- and perinatally acting cerebral noxae cause disturbances of corticogenesis in the developing neuronal fibre systems which are essential for later onset of the disease. During recent years the cerebral alterations of schizophrenic patients could be further characterized as area-, layer-, and cell type-specific changes in temporolimbic and frontal regions leading to specific abnormalities of intrinsic and extrinsic connectivity. Animal models allowed for realistic imitations of these structural lesions and for elucidating their functional consequences concerning transmitter systems and behaviour. With modern neuroimaging techniques microstructural changes and alterations in cerebral activation can be exactly demonstrated and related to the specific psychopathologic features of schizophrenia.
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Affiliation(s)
- P Kalus
- Psychiatrische Universitätsklinik der Charité im St. Hedwig Krankenhaus, Grosse Hamburger Strasse 5-11, 10115 Berlin.
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35
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Konrad A, Winterer G. Disturbed structural connectivity in schizophrenia primary factor in pathology or epiphenomenon? Schizophr Bull 2008; 34:72-92. [PMID: 17485733 PMCID: PMC2632386 DOI: 10.1093/schbul/sbm034] [Citation(s) in RCA: 158] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Indirect evidence for disturbed structural connectivity of subcortical fiber tracts in schizophrenia has been obtained from functional neuroimaging and electrophysiologic studies. During the past few years, new structural imaging methods have become available. Diffusion tensor imaging and magnetization transfer imaging (MTI) have been used to investigate directly whether fiber tract abnormalities are indeed present in schizophrenia. To date, findings are inconsistent that may express problems related to methodological issues and sample size. Also, pathological processes detectable with these new techniques are not yet well understood. Nevertheless, with growing evidence of disturbed structural connectivity, myelination has been in the focus of postmortem investigations. Several studies have shown a significant reduction of oligodendroglial cells and ultrastructural alterations of myelin sheats in schizophrenia. There is also growing evidence for abnormal expression of myelin-related genes in schizophrenia: Neuregulin (NRG1) is important for oligodendrocyte development and function, and altered expression of erbB3, one of the NRG1 receptors, has been shown in schizophrenia patients. This is consistent with recent genetic studies suggesting that NRG1 may contribute to the genetic risk for schizophrenia. In conclusion, there is increasing evidence from multiple sides that structural connectivity might be pathologically changed in schizophrenia illness. Up to the present, however, it has not been possible to decide whether alterations of structural connectivity are intrinsically linked to the primary risk factors for schizophrenia or to secondary downstream effects (ie, degeneration of fibers secondarily caused by cortical neuronal dysfunction)-an issue that needs to be clarified by future research.
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Affiliation(s)
- Andreas Konrad
- Department of Psychiatry, Johannes Gutenberg-University, Mainz, Germany.
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Fanous AH, Chen X, Wang X, Amdur RL, O'Neill FA, Walsh D, Kendler KS. Association between the 5q31.1 gene neurogenin1 and schizophrenia. Am J Med Genet B Neuropsychiatr Genet 2007; 144B:207-14. [PMID: 17044100 DOI: 10.1002/ajmg.b.30423] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Multiple lines of evidence suggest that schizophrenia results from aberrant neurodevelopment. The neurogenin1 gene (neurog1) consists of a single 1,666 bp exon that encodes a basic helix-loop-helix (bHLH) transcription factor that causes neuronal differentiation and induces cortical and glutamatergic differentiation programs. Because of its function and its location in 5q31.1, which has been linked to schizophrenia in multiple samples, we tested it for association with the disorder. We sequenced neurog1 in 25 affected subjects from the Irish Study of High-Density Schizophrenia Families. We observed a 5'-UTR SNP at position -60, already present in databases as rs8192558, and tested it along with rs2344485, rs8192559, and rs2344484. Narrow, intermediate, and broad diagnostic definitions were used. The major alleles of rs8192558 and rs2344484 were over-transmitted to affected subjects using both Pedigree Disequilibrium Test (PDT) (0.01 < or = P < or = 0.06) and FBAT (0.02 < or = P < or = 0.07). A haplotype consisting of the major alleles of all four SNPs was significantly over-transmitted in FBAT to the broad definition (P = 0.049), with trend significance to the narrow and intermediate definitions, and with trend significance in PDT. In confirmatory tests using 657 cases and 411 controls, this haplotype was slightly but not significantly over-represented in cases (81% vs. 77%, P = 0.21). These results, along with a priori evidence for the involvement of neurog1 in neurodevelopment, suggest that variants in neurog1 might have a small effect on susceptibility to schizophrenia. This gene should be tested in additional and larger samples.
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Affiliation(s)
- Ayman H Fanous
- Washington VA Medical Center, Washington, District of Columbia, USA.
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Thermenos HW, Seidman LJ, Poldrack RA, Peace NK, Koch JK, Faraone SV, Tsuang MT. Elaborative verbal encoding and altered anterior parahippocampal activation in adolescents and young adults at genetic risk for schizophrenia using FMRI. Biol Psychiatry 2007; 61:564-74. [PMID: 17276751 DOI: 10.1016/j.biopsych.2006.04.044] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2005] [Revised: 04/20/2006] [Accepted: 04/21/2006] [Indexed: 10/23/2022]
Abstract
BACKGROUND First-degree relatives of persons with schizophrenia are at elevated risk for the illness, demonstrate deficits in verbal memory, and exhibit structural abnormalities in the medial temporal lobe (MTL). We used functional magnetic resonance imaging (fMRI) to assess brain activity in the MTL during novel and repeated word-pair encoding. METHODS Participants were 21 non-psychotic, first-degree relatives of persons with schizophrenia and 26 matched healthy controls (ages 13-28). fMRI signal change was measured using a Siemens 1.5T MR scanner, and data were analyzed using SPM-2. Verbal memory was assessed using the Miller Selfridge (MS) Context Memory test prior to scanning. RESULTS The groups were comparable on demographics, intelligence and post-scan word recognition. Relatives at genetic risk (GR) had significantly more psychopathology than controls and worse performance on the MS test (p < .05). GR participants exhibited greater repetition suppression of activation in the left and right anterior parahippocampus (PHA, in the region of the entorhinal cortex region), after controlling for possible confounders. Controls and GR participants with above-median MS performance showed significantly greater repetition suppression of activation in left inferior frontal gyrus than those scoring below the median. CONCLUSIONS This is the first study to demonstrate an alteration of brain activity in the PHA in persons at GR for schizophrenia.
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Affiliation(s)
- Heidi W Thermenos
- Harvard Medical School, Massachusetts Mental Health Center in the Division of Public Psychiatry, Department of Psychiatry, Beth Israel Deaconess Medical Center, Boston, USA.
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Boyer P, Phillips JL, Rousseau FL, Ilivitsky S. Hippocampal abnormalities and memory deficits: new evidence of a strong pathophysiological link in schizophrenia. ACTA ACUST UNITED AC 2007; 54:92-112. [PMID: 17306884 DOI: 10.1016/j.brainresrev.2006.12.008] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Revised: 10/07/2006] [Accepted: 12/20/2006] [Indexed: 12/11/2022]
Abstract
The central goals of this manuscript are (1) to better characterize what appears to be the most parsimonious account of schizophrenic long-term memory impairment in the neuropsychological literature: a contextual binding deficit rooted in the medial temporal lobes; (2) to link this deficit to concrete abnormalities at the level of the hippocampus; and (3) to suggest that this deficit could lead to the functional impairment experienced by schizophrenia patients in their daily lives. As far as long-term memory is concerned in schizophrenia, there seems to be a general agreement to conclude that explicit mechanisms are disturbed compared to relatively spared implicit mechanisms. More precisely, both subsystems of explicit memory (i.e., episodic and semantic) appear to be dysfunctional in this patient population. Errors during the encoding processes could be responsible for this dysfunction even if retrieval per se is not totally spared. Recently, a number of studies have suggested that impairments in conscious recollection and contextual binding are closely linked to episodic memory deficit. Since the hippocampal formation is considered to be the central element in the neural support for contextual binding and episodic memory, we have conducted an extensive review of the literature concerning the hippocampal formation in schizophrenia. Emerging evidence from varying disciplines confirm the coherence of the different anomalies reported concurrently at the neuroanatomical, neurodevelopmental, biochemical, and genetic levels. It seems highly probable that the synaptic disorganization in the hippocampus concerns the regions crucial for encoding and contextual binding memory processes. The consequences of these deficits could result in schizophrenia patients experiencing major difficulties when facing usual events which have not been encoded with their proper context.
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Affiliation(s)
- Patrice Boyer
- Schizophrenia Research Unit, University of Ottawa Institute of Mental Health Research, 1145 Carling, Ottawa, Ontario, Canada K1Z 7K4.
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Abstract
With its hallucinations, delusions, thought disorder, and cognitive deficits, schizophrenia affects the most basic human processes of perception, emotion, and judgment. Evidence increasingly suggests that schizophrenia is a subtle disorder of brain development and plasticity. Genetic studies are beginning to identify proteins of candidate genetic risk factors for schizophrenia, including dysbindin, neuregulin 1, DAOA, COMT, and DISC1, and neurobiological studies of the normal and variant forms of these genes are now well justified. We suggest that DISC1 may offer especially valuable insights. Mechanistic studies of the properties of these candidate genes and their protein products should clarify the molecular, cellular, and systems-level pathogenesis of schizophrenia. This can help redefine the schizophrenia phenotype and shed light on the relationship between schizophrenia and other major psychiatric disorders. Understanding these basic pathologic processes may yield novel targets for the development of more effective treatments.
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Affiliation(s)
- Christopher A Ross
- Division of Neurobiology, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21287, USA.
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Henriksson KM, Kelly BD, Lane A, Hult R, McNeil TF, Agartz I. A morphometric magnetic resonance method for measuring cranial, facial and brain characteristics for application to schizophrenia: part 1. Psychiatry Res 2006; 147:173-86. [PMID: 16952447 DOI: 10.1016/j.pscychresns.2005.02.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2004] [Revised: 09/26/2004] [Accepted: 02/14/2005] [Indexed: 10/24/2022]
Abstract
Serious psychopathology in adulthood may be associated with disturbed foetal brain development, which potentially shows lingering "fossil marks" in the cranial and facial regions. Several methods exist for assessing external craniofacial and internal brain distances but, to our knowledge, no method yet provides simultaneous measurement of cranial, facial and brain dimensions in live subjects. In this article we describe a method to identify landmarks on magnetic resonance images (MRI) for simultaneous measurement of cranial, facial and brain characteristics potentially associated with psychosis. To test the method itself, 30 patients with chronic schizophrenia and 31 healthy comparison subjects, mean age 41 years, were randomly selected from a larger cohort recruited at the Karolinska Hospital, Sweden. Participants were investigated with MRI, and 60 landmarks in the cranial, facial and brain regions were identified in the images. An independent anthropometric examination measured external craniofacial characteristics for study in relation to measurements produced through MRI. High inter-scorer and re-test reliabilities were obtained for two independent scorers of the landmarks in the MR images. Measurements of potentially comparable craniofacial distances showed high alignment with an established anthropometric method. This new method can provide simultaneous investigation of multiple aspects of cranial, facial and brain morphology in MR images originally collected for other purposes. In a second article we will use this method to compare 3D craniofacial measurements and shape between schizophrenia patients and healthy controls.
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Affiliation(s)
- Karin M Henriksson
- Department of Psychiatric Epidemiology, University Hospital, Lund University, Barngatan 2, S- 221 85, Lund, Sweden.
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41
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Abstract
Several structural deviances in the brain in "endogenous psychoses" have been described over the last decades. The enlargement of the lateral ventricles and the subtle structural deficits in temporobasal and orbital frontal structures (hypofrontality) are reasonably well established in the majority of schizophrenic patients. We examined the cytoarchitecture of these important central structures, namely the entorhinal region and the orbitofrontal cortex (Brodmann area 11), which have been under meticulous investigation in our laboratories over the last few decades. In a new series of schizophrenic patients and normal controls, we made serial cuts of the whole rostral entorhinal cortex on both sides. For this report, we selected two cases with very different psychopathologies, and present the serial cuts through both hemispheres and the malformations found. We report on the differing magnitude of the heterotopic malformations (for definition see page 103), either bilaterally or unilaterally.
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Affiliation(s)
- Helmut Beckmann
- Clinic and Polyclinic of Psychiatry and Psychotherapy, University of Wuerzburg, Wuerzburg, Germany.
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Beasley CL, Chana G, Honavar M, Landau S, Everall IP, Cotter D. Evidence for altered neuronal organisation within the planum temporale in major psychiatric disorders. Schizophr Res 2005; 73:69-78. [PMID: 15567079 DOI: 10.1016/j.schres.2004.08.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2004] [Revised: 08/13/2004] [Accepted: 08/19/2004] [Indexed: 11/25/2022]
Abstract
Reductions in neuronal size and glial cell density have been described in the frontal cortex in major psychiatric disorders. In this investigation, we performed a cytoarchitectural assessment within the planum temporale (PT), an auditory association region located within the superior temporal gyrus, using two-dimensional (2D) measures of cell size and density and spatial point pattern analysis. In sections of the PT from subjects with schizophrenia, bipolar disorder, major depressive disorder and controls (15 subjects per group), the laminar distribution and size of all neurons and glial cell nuclei was recorded. Spatial point pattern investigation demonstrated reduced neuronal clustering in bipolar disorder (p=0.033) and schizophrenia (p=0.027) compared with controls. Statistical analyses comparing each of the patient groups with the control group failed to identify differences in neuronal density between groups. Neuronal size was reduced in cortical layer 3 (p=0.02) and glial cell density reduced in cortical layer 6 (p=0.05) in bipolar disorder relative to controls but these findings did not remain significant after adjusting for six layer-wise comparisons. We propose that alterations in cortical cytoarchitecture within this region are subtle and involve reduced clustering of neurons, which may be due to altered neuronal organisation within cortical mini-columns or within cortical layers.
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Affiliation(s)
- Clare L Beasley
- Department of Neuropathology, Institute of Psychiatry, DeCrespigny Park, London SE5 8AF, UK.
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Kalus P, Slotboom J, Gallinat J, Federspiel A, Gralla J, Remonda L, Strik WK, Schroth G, Kiefer C. New evidence for involvement of the entorhinal region in schizophrenia: a combined MRI volumetric and DTI study. Neuroimage 2005; 24:1122-9. [PMID: 15670689 DOI: 10.1016/j.neuroimage.2004.10.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2004] [Revised: 09/08/2004] [Accepted: 10/06/2004] [Indexed: 11/24/2022] Open
Abstract
Postmortem examinations and magnetic resonance imaging (MRI) studies suggest involvement of the entorhinal cortex (EC) in schizophrenic psychoses. However, the extent and nature of the possible pathogenetical process underlying the observed alterations of this limbic key region for processing of multimodal sensory information remains unclear. Three-dimensional high-resolution MRI volumetry and evaluation of the regional diffusional anisotropy based on diffusion tensor imaging (DTI) were performed on the EC of 15 paranoid schizophrenic patients and 15 closely matched control subjects. In schizophrenic patients, EC volumes showed a slight, but not significant, decrease. However, the anisotropy values, expressed as inter-voxel coherences (COH), were found to be significantly decreased by 17.9% (right side) and 12.5% (left side), respectively, in schizophrenics. Reduction of entorhinal diffusional anisotropy can be hypothesized to be functionally related to disturbances in the perforant path, the principal efferent EC fiber tract supplying the limbic system with neuronal input from multimodal association centers. Combinations of different MRI modalities are a promising approach for the detection and characterization of subtle brain tissue alterations.
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Affiliation(s)
- Peter Kalus
- Clinic for Psychiatry and Psychotherapy, Charité University Medicine, Campus Mitte, Turmstrasse 21, D-10559 Berlin, Germany.
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Arnold SE, Talbot K, Hahn CG. Neurodevelopment, neuroplasticity, and new genes for schizophrenia. PROGRESS IN BRAIN RESEARCH 2005; 147:319-45. [PMID: 15581715 DOI: 10.1016/s0079-6123(04)47023-x] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Schizophrenia is a complex, debilitating neuropsychiatric disorder. Epidemiological, clinical, neuropsychological, and neurophysiological studies have provided substantial evidence that abnormalities in brain development and ongoing neuroplasticity play important roles in the pathogenesis of the disorder. Complementing these clinical studies, a range of cytoarchitectural, morphometric, ultrastructural, immunochemical, and gene expression methods have been applied in investigations of postmortem brain tissues to characterize the cellular and molecular profile of putative developmental and plastic abnormalities in schizophrenia. While findings have been diverse and many are in need of replication, investigations focusing on higher cortical and limbic brain regions are increasingly demonstrating abnormalities in the structural and molecular integrity of the synaptic complex as well as glutamate-related receptors and signal transduction pathways that play critical roles in brain development, synaptogenesis, and synaptic plasticity. Most exciting have been recent associations of schizophrenia with specific genes, such as neuregulin-1, dysbindin-1, and AKT-1, which are vital to synaptic development, neurotransmission, and plasticity.
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Affiliation(s)
- Steven E Arnold
- Cellular and Molecular Neuropathology Program, Center for Neurobiology and Behavior, Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, USA.
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45
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Sumiyoshi T, Tsunoda M, Uehara T, Tanaka K, Itoh H, Sumiyoshi C, Kurachi M. Enhanced locomotor activity in rats with excitotoxic lesions of the entorhinal cortex, a neurodevelopmental animal model of schizophrenia: Behavioral and in vivo microdialysis studies. Neurosci Lett 2004; 364:124-9. [PMID: 15196692 DOI: 10.1016/j.neulet.2004.04.027] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2004] [Revised: 04/12/2004] [Accepted: 04/13/2004] [Indexed: 11/16/2022]
Abstract
In order to examine the construct validity of rats with excitotoxic damage of the left entorhinal cortex (EC) as an animal model of schizophrenia, we measured dopamine (DA)-related behaviors and methamphetamine (MAP)-induced DA release in the accumbens nucleus (NAC) in these animals. Quinolinic acid (lesion group) or phosphate buffer (sham group) was infused into the left EC of adolescent (postnatal 7 weeks) male Wistar rats. On the 14th and 28th postoperative day, spontaneous and MAP (1 mg/kg, i.p.)-induced locomotor activities, as well as MAP-induced stereotypy, were measured. The lesioned rats exhibited significantly greater spontaneous or MAP-induced locomotor activity on both of the postoperative days than did sham-operated animals, while EC lesions did not affect MAP-induced stereotypy on either occasion. MAP (1 mg/kg, i.p.)-induced DA release in NAC was measured by in vivo microdialysis on the 28th postoperative day. Lesioned rats did not show a significant change in MAP (1 mg/kg, i.p.)-induced DA release in NAC compared to sham-operated animals. These results suggest that excitotoxic damage of the left EC produces behavioral changes consistent with altered mesolimbic dopaminergic transmissions, possibly mediated by postsynaptic supersensitivity.
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Affiliation(s)
- Tomiki Sumiyoshi
- Department of Neuropsychiatry, Toyama Medical and Pharmaceutical University, School of Medicine, 2630 Sugitani, Toyama 930-0194, Japan.
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Harrison PJ. The hippocampus in schizophrenia: a review of the neuropathological evidence and its pathophysiological implications. Psychopharmacology (Berl) 2004; 174:151-62. [PMID: 15205886 DOI: 10.1007/s00213-003-1761-y] [Citation(s) in RCA: 518] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2003] [Accepted: 11/25/2003] [Indexed: 01/17/2023]
Abstract
This paper puts the case for the hippocampus as being central to the neuropathology and pathophysiology of schizophrenia. The evidence comes from a range of approaches, both in vivo (neuropsychology, structural and functional imaging) and post mortem (histology, morphometry, gene expression, and neurochemistry). Neuropathologically, the main positive findings concern neuronal morphology, organisation, and presynaptic and dendritic parameters. The results are together suggestive of an altered synaptic circuitry or "wiring" within the hippocampus and its extrinsic connections, especially with the prefrontal cortex. These changes plausibly represent the anatomical component of the aberrant functional connectivity that underlies schizophrenia. Glutamatergic pathways are prominently but not exclusively affected. Changes appear somewhat greater in the left hippocampus than the right, and CA1 is relatively uninvolved compared to other subfields. Hippocampal pathology in schizophrenia may be due to genetic factors, aberrant neurodevelopment, and/or abnormal neural plasticity; it is not due to any recognised neurodegenerative process. Hippocampal involvement is likely to be associated with the neuropsychological impairments of schizophrenia rather than with its psychotic symptoms.
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Affiliation(s)
- Paul J Harrison
- Department of Psychiatry, Neurosciences Building, Warneford Hospital, University of Oxford, Oxford, OX3 7JX, UK.
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Jeanblanc J, Peterschmitt Y, Hoeltzel A, Louilot A. Influence of the entorhinal cortex on accumbal and striatal dopaminergic responses in a latent inhibition paradigm. Neuroscience 2004; 128:187-200. [PMID: 15450366 DOI: 10.1016/j.neuroscience.2004.06.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/23/2004] [Indexed: 11/25/2022]
Abstract
The use of latent inhibition paradigms is one means of investigating the involvement of mesencephalic dopaminergic (DA) neurons in cognitive processes. We have shown recently that DA neurons reaching the core and the dorsomedial shell parts of the nucleus accumbens and the anterior part of the striatum are differentially involved in latent inhibition. In other respects, theoretical, behavioral and anatomo-functional data suggest that the entorhinal cortex (ENT) may control latent inhibition expression. In this study, using in vivo voltammetry in freely moving rats, we investigated the influence of the ENT on the DA responses obtained in the core and dorsomedial shell parts of the nucleus accumbens and the anterior part of the striatum. For this purpose a reversible inactivation of the left ENT was achieved by the local microinjection of tetrodotoxin, 3 h before pre-exposure to the conditional stimulus (banana odour). During the second session, animals were aversively conditioned to banana odour. Results obtained during the third session (test session), in animals submitted to the reversible blockade of the ENT before the first session were as follows: (1) pre-exposed conditioned animals displayed behavioral aversive responses; (2) where core DA responses were concerned, responses were situated between those observed in pre-exposed and non-pre-exposed conditioned animals; (3) by contrast, where the dorsomedial shell part of the nucleus accumbens and the anterior striatum were concerned, DA variations were not statistically different in pre-exposed and non-pre-exposed conditioned rats. These data suggest that the left ENT exerts a crucial influence over the latent-inhibition-related DA responses in the left dorsomedial shell part of the nucleus accumbens and the left anterior part of the striatum, whereas one or more other brain regions control DA variations in the left core part of the nucleus accumbens. These data may help us to understand the pathophysiology of schizophrenic psychoses.
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Affiliation(s)
- J Jeanblanc
- INSERM U 405 and Institute of Physiology, Louis Pasteur University, Faculty of Medicine, 11 rue Humann, 67085 Strasbourg Cedex, France
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Seillier A, Coutureau E, Thiriet N, Herbeaux K, Zwiller J, Di Scala G, Will B, Majchrzak M. Bilateral lesions of the entorhinal cortex differentially modify haloperidol- and olanzapine-induced c-fos mRNA expression in the rat forebrain. Neuropharmacology 2003; 45:190-200. [PMID: 12842125 DOI: 10.1016/s0028-3908(03)00147-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Lesions of the entorhinal cortex are now an accepted model for mimicking some of the neuropathological aspects of schizophrenia, since evidence has accumulated for the presence of cytoarchitectonic abnormalities within this cortex in schizophrenic patients. The present study was undertaken to address the functional consequences of bilateral entorhinal cortex lesions on antipsychotic-induced c-fos expression. After a 15-day recovery period, the effect of a typical antipsychotic, haloperidol (1 mg/kg), on c-fos mRNA expression was compared with that of an atypical one, olanzapine (10 mg/kg), in both sham-lesioned and entorhinal cortex-lesioned rats. In sham-lesioned rats, both haloperidol and olanzapine induced c-fos expression in the caudal cingulate cortex, dorsomedial and dorsolateral caudate-putamen, nucleus accumbens core and shell and lateral septum. In addition, olanzapine, but not haloperidol, increased c-fos expression within the central amygdala. In entorhinal cortex-lesioned rats, haloperidol-induced c-fos expression was markedly reduced in most areas. In contrast, the olanzapine-induced c-fos expression was not altered in the nucleus accumbens shell and lateral septum of the lesioned rats. These findings reveal that entorhinal cortex lesions affect c-fos expression in a compound- and regional-dependent manner. Our results further emphasize the importance of the exploration of the mechanisms of action of antipsychotic drugs in the context of an associated cortical pathology.
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Affiliation(s)
- A Seillier
- Laboratoire de Neurosciences Comportementales et Cognitives, UMR 7521, Université Louis Pasteur, CNRS, IFR des Neurosciences, Strasbourg, France.
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Chana G, Landau S, Beasley C, Everall IP, Cotter D. Two-dimensional assessment of cytoarchitecture in the anterior cingulate cortex in major depressive disorder, bipolar disorder, and schizophrenia: evidence for decreased neuronal somal size and increased neuronal density. Biol Psychiatry 2003; 53:1086-98. [PMID: 12814860 DOI: 10.1016/s0006-3223(03)00114-8] [Citation(s) in RCA: 197] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Abnormalities of cortical neuronal organization and reductions in neuronal somal size have been reported in schizophrenia. The purpose of this investigation was to assess patterns of neuronal and glial distribution in the anterior cingulate cortex (ACC) in major depressive disorder (MDD), schizophrenia, bipolar disorder (BPD), and normal control subjects (15 subjects per group). METHODS Estimates for neuronal somal and glial nuclear size and density were obtained. We employed two-dimensional morphometric analysis to examine the location of neurons and glia in a 1000-microm-wide strip of cortex. RESULTS A decreased clustering of neurons was seen in BPD (p =.001). No other group differences were observed in the clustering of neurons, glia, or of neurons about glia. Neuronal somal size was reduced in layer 5 in schizophrenia (18%, p =.001), BPD (16%, p <.001), and MDD (9%, p =.01). Neuronal density was increased in layer 6 in BPD (63%, p =.004) and schizophrenia (61%, p =.006) and in layer 5 in MDD (24%, p =.018) and schizophrenia (33%, p =.003). CONCLUSIONS The results of this study indicate that reduced neuronal somal size and increased neuronal density in cortical layers 5 and 6 of the ACC may be key features of schizophrenia, MDD, and BPD.
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Affiliation(s)
- Gursharan Chana
- Department of Psychological Medicine, Section of Experimental Neuropathology and Psychiatry, Institute of Psychiatry, DeCrespigny Park, London, United Kingdom
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50
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Abstract
Schizophrenia is a common and debilitating illness, characterized by chronic psychotic symptoms and psychosocial impairment that exact considerable human and economic costs. The literature in electronic databases as well as citations and major articles are reviewed with respect to the phenomenology, pathology, treatment, genetics and neurobiology of schizophrenia. Although studied extensively from a clinical, psychological, biological and genetic perspective, our expanding knowledge of schizophrenia provides only an incomplete understanding of this complex disorder. Recent advances in neuroscience have allowed the confirmation or refutation of earlier findings in schizophrenia, and permit useful comparisons between the different levels of organization from which the illness has been studied. Schizophrenia is defined as a clinical syndrome that may include a collection of diseases that share a common presentation. Genetic factors are the most important in the etiology of the disease, with unknown environmental factors potentially modulating the expression of symptoms. Schizophrenia is a complex genetic disorder in which many genes may be implicated, with the possibility of gene-gene interactions and a diversity of genetic causes in different families or populations. A neurodevelopmental rather than degenerative process has received more empirical support as a general explanation of the pathophysiology, although simple dichotomies are not particularly helpful in such a complicated disease. Structural brain changes are present in vivo and post-mortem, with both histopathological and imaging studies in overall agreement that the temporal and frontal lobes of the cerebral cortex are the most affected. Functional imaging, neuropsychological testing and clinical observation are also generally consistent in demonstrating deficits in cognitive ability that correlate with abnormalities in the areas of the brain with structural abnormalities. The dopamine and other neurotransmitter systems are certainly involved in the treatment or modulation of psychotic symptoms. These broad findings represent the distillation of a large body of disparate data, but firm and specific findings are sparse, and much about schizophrenia remains unknown.
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Affiliation(s)
- Albert Hung Choy Wong
- Centre for Addiction and Mental Health, 250 College Street, M5T 1R8, Toronto, Ont., Canada.
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