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Liu X, Liu Z, Wang F, Cheng P, Yang J, Tan W, Cheng Y, Huang D, Xiang Z, Zhang J, Li J, Xie Y, Zhong M, Yang J. A connectome-based model of delusion in schizophrenia using functional connectivity under working memory task. J Psychiatr Res 2024; 177:75-81. [PMID: 38981411 DOI: 10.1016/j.jpsychires.2024.07.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Revised: 06/30/2024] [Accepted: 07/03/2024] [Indexed: 07/11/2024]
Abstract
Delusion is an important feature of schizophrenia, which may stem from cognitive biases. Working memory (WM) is the core foundation of cognition, closely related to delusion. However, the knowledge of neural mechanisms underlying the relationship between WM and delusion in schizophrenia is poorly investigated. Two hundred and thirty patients with schizophrenia (dataset 1: n = 130; dataset 2: n = 100) were enrolled and scanned for an N-back WM task. We constructed the WM-related whole-brain functional connectome and conducted Connectome-based Predictive Modelling (CPM) to detect the delusion-related networks and built the correlation model in dataset 1. The correlation between identified networks and delusion severity was tested in a separate, heterogeneous sample of dataset 2 that mainly includes early-onset schizophrenia. The identified delusion-related network has a strong correlation with delusion severity measured by the NO.20 item of SAPS in dataset 1 (r = 0.433, p = 2.7 × 10-7, permutation-p = 0.035), and can be validated in the same dataset by using another delusion measurement, that is, the P1 item of PANSS (r = 0.362, p = 0.0005). It can be validated in another independent dataset 2 (NO.20 item of SAPS for r = 0.31, p = 0.0024, P1 item of PANSS for r = 0.27, p = 0.0074). The delusion-related network comprises the connections between the default mode network (DMN), cingulo-opercular network (CON), salience network (SN), subcortical, sensory-somatomotor network (SMN), and visual networks. We successfully established correlation models of individualized delusion based on the WM-related functional connectome and showed a strong correlation between delusion severity and connections within the DMN, CON, SMN, and subcortical network.
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Affiliation(s)
- Xiawei Liu
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China
| | - Zhening Liu
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China
| | - Feiwen Wang
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China
| | - Peng Cheng
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China
| | - Jun Yang
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China
| | - Wenjian Tan
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China
| | - Yixin Cheng
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China
| | - Danqing Huang
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China
| | - Zhibiao Xiang
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China
| | - Jiamei Zhang
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China
| | - Jinyue Li
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China
| | - Yuxin Xie
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China
| | - Maoxing Zhong
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China
| | - Jie Yang
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, 410011, Hunan, China.
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Zhang QX, Wu SS, Wang PJ, Zhang R, Valenzuela RK, Shang SS, Wan T, Ma J. Schizophrenia-Like Deficits and Impaired Glutamate/Gamma-aminobutyric acid Homeostasis in Zfp804a Conditional Knockout Mice. Schizophr Bull 2024:sbae120. [PMID: 38988003 DOI: 10.1093/schbul/sbae120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 07/12/2024]
Abstract
BACKGROUND AND HYPOTHESIS Zinc finger protein 804A (ZNF804A) was the first genome-wide associated susceptibility gene for schizophrenia (SCZ) and played an essential role in the pathophysiology of SCZ by influencing neurodevelopment regulation, neurite outgrowth, synaptic plasticity, and RNA translational control; however, the exact molecular mechanism remains unclear. STUDY DESIGN A nervous-system-specific Zfp804a (ZNF804A murine gene) conditional knockout (cKO) mouse model was generated using clustered regularly interspaced short palindromic repeat/Cas9 technology and the Cre/loxP method. RESULTS Multiple and complex SCZ-like behaviors, such as anxiety, depression, and impaired cognition, were observed in Zfp804a cKO mice. Molecular biological methods and targeted metabolomics assay validated that Zfp804a cKO mice displayed altered SATB2 (a cortical superficial neuron marker) expression in the cortex; aberrant NeuN, cleaved caspase 3, and DLG4 (markers of mature neurons, apoptosis, and postsynapse, respectively) expressions in the hippocampus and a loss of glutamate (Glu)/γ-aminobutyric acid (GABA) homeostasis with abnormal GAD67 (Gad1) expression in the hippocampus. Clozapine partly ameliorated some SCZ-like behaviors, reversed the disequilibrium of the Glu/GABA ratio, and recovered the expression of GAD67 in cKO mice. CONCLUSIONS Zfp804a cKO mice reproducing SCZ-like pathological and behavioral phenotypes were successfully developed. A novel mechanism was determined in which Zfp804a caused Glu/GABA imbalance and reduced GAD67 expression, which was partly recovered by clozapine treatment. These findings underscore the role of altered gene expression in understanding the pathogenesis of SCZ and provide a reliable SCZ model for future therapeutic interventions and biomarker discovery.
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Affiliation(s)
- Qiao-Xia Zhang
- Department of Electron Microscope, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Shan-Shan Wu
- Department of Electron Microscope, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Peng-Jie Wang
- Department of Electron Microscope, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Rui Zhang
- Department of Electron Microscope, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
- Department of Biochemistry and Molecular Biology, College of Medical Technology, Guiyang Healthcare Vocational University, Guiyang, Guizhou, China
| | - Robert K Valenzuela
- JAX Center for Alzheimer's and Dementia Research, The Jackson Laboratory, Bar Harbor, ME, USA
| | - Shan-Shan Shang
- Department of Electron Microscope, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Ting Wan
- Department of Electron Microscope, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Jie Ma
- Department of Electron Microscope, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
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Nelson EA, Kraguljac NV, Maximo JO, Armstrong W, Lahti AC. Hippocampal Hyperconnectivity to the Visual Cortex Predicts Treatment Response. Schizophr Bull 2023; 49:605-613. [PMID: 36752830 PMCID: PMC10154738 DOI: 10.1093/schbul/sbac213] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
BACKGROUND Converging lines of evidence point to hippocampal dysfunction in psychosis spectrum disorders, including altered functional connectivity. Evidence also suggests that antipsychotic medications can modulate hippocampal dysfunction. The goal of this project was to identify patterns of hippocampal connectivity predictive of response to antipsychotic treatment in 2 cohorts of patients with a psychosis spectrum disorder, one medication-naïve and the other one unmedicated. HYPOTHESIS We hypothesized that we would identify reliable patterns of hippocampal connectivity in the 2 cohorts that were predictive of treatment response and that medications would modulate abnormal hippocampal connectivity after 6 weeks of treatment. STUDY DESIGN We used a prospective design to collect resting-state fMRI scans prior to antipsychotic treatment and after 6 weeks of treatment with risperidone, a commonly used antipsychotic medication, in both cohorts. We enrolled 44 medication-naïve first-episode psychosis patients (FEP) and 39 unmedicated patients with schizophrenia (SZ). STUDY RESULTS In both patient cohorts, we observed a similar pattern where greater hippocampal connectivity to regions of the occipital cortex was predictive of treatment response. Lower hippocampal connectivity of the frontal pole, orbitofrontal cortex, subcallosal area, and medial prefrontal cortex was predictive of treatment response in unmedicated SZ, but not in the medication-naïve cohort. Furthermore, greater reduction in hippocampal connectivity to the visual cortex with treatment was associated with better clinical response. CONCLUSIONS Our results suggest that greater connectivity between the hippocampus and occipital cortex is not only predictive of better treatment response, but that antipsychotic medications have a modulatory effect by reducing hyperconnectivity.
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Affiliation(s)
- Eric A Nelson
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Nina V Kraguljac
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jose O Maximo
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - William Armstrong
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Adrienne C Lahti
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
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Lahti AC. Discovery of early schizophrenia through neuroimaging. Psychiatry Res 2023; 322:114993. [PMID: 36773467 DOI: 10.1016/j.psychres.2022.114993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 11/22/2022] [Accepted: 11/27/2022] [Indexed: 11/29/2022]
Abstract
In order to understand the pathophysiology of schizophrenia we carried out a number of brain imaging studies in both medicated and unmedicated patients. In addition, to help unravel the pathophysiological mechanisms without the confound of prior exposure to antipsychotic medication or chronicity, we enrolled a large group of antipsychotic medication-naïve first episode psychosis patients at first treatment contact, and performed longitudinal multimodal neuroimaging studies over several months. In unmedicated patients we found both functional and structural connectivity alterations. Similarly, in medication-naïve patients we replicated many of our prior findings, suggesting that functional and structural connectivity alterations are core pathological features of the illness. We found that a longer duration of untreated psychosis, i.e. the time between first symptom onset and initial treatment contact, was associated with greater structural and functional connectivity abnormalities, which in turn was associated with worse subsequent clinical response to treatment. These results underscore the critical importance of early identification and treatment in patients with psychosis spectrum disorders.
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Affiliation(s)
- Adrienne C Lahti
- Department of Psychiatry and Behavioral Neurobiology, The University of Alabama at Birmingham, Birmingham, AL, United States.
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Ravanfar P, Syeda WT, Jayaram M, Rushmore RJ, Moffat B, Lin AP, Lyall AE, Merritt AH, Yaghmaie N, Laskaris L, Luza S, Opazo CM, Liberg B, Chakravarty MM, Devenyi GA, Desmond P, Cropley VL, Makris N, Shenton ME, Bush AI, Velakoulis D, Pantelis C. In Vivo 7-Tesla MRI Investigation of Brain Iron and Its Metabolic Correlates in Chronic Schizophrenia. SCHIZOPHRENIA (HEIDELBERG, GERMANY) 2022; 8:86. [PMID: 36289238 PMCID: PMC9605948 DOI: 10.1038/s41537-022-00293-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 09/30/2022] [Indexed: 06/16/2023]
Abstract
Brain iron is central to dopaminergic neurotransmission, a key component in schizophrenia pathology. Iron can also generate oxidative stress, which is one proposed mechanism for gray matter volume reduction in schizophrenia. The role of brain iron in schizophrenia and its potential link to oxidative stress has not been previously examined. In this study, we used 7-Tesla MRI quantitative susceptibility mapping (QSM), magnetic resonance spectroscopy (MRS), and structural T1 imaging in 12 individuals with chronic schizophrenia and 14 healthy age-matched controls. In schizophrenia, there were higher QSM values in bilateral putamen and higher concentrations of phosphocreatine and lactate in caudal anterior cingulate cortex (caCC). Network-based correlation analysis of QSM across corticostriatal pathways as well as the correlation between QSM, MRS, and volume, showed distinct patterns between groups. This study introduces increased iron in the putamen in schizophrenia in addition to network-wide disturbances of iron and metabolic status.
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Affiliation(s)
- Parsa Ravanfar
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Carlton South, VIC, Australia.
- Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
| | - Warda T Syeda
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Carlton South, VIC, Australia
| | - Mahesh Jayaram
- Department of Psychiatry, The University of Melbourne and Melbourne Health, Parkville, Australia
| | - R Jarrett Rushmore
- Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
- Center for Morphometric Analysis (CMA), Massachusetts General Hospital, Charlestown, MA, USA
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA, USA
| | - Bradford Moffat
- Melbourne Brain Centre Imaging Unit, Department of Radiology, University of Melbourne, Parkville, VIC, Australia
| | - Alexander P Lin
- Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
- Department of Radiology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Amanda E Lyall
- Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
- Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Antonia H Merritt
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Carlton South, VIC, Australia
| | - Negin Yaghmaie
- Melbourne Brain Centre Imaging Unit, Department of Radiology, University of Melbourne, Parkville, VIC, Australia
- Department of Biomedical Engineering, The University of Melbourne, Parkville, VIC, Australia
| | - Liliana Laskaris
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Carlton South, VIC, Australia
| | - Sandra Luza
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Carlton South, VIC, Australia
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience & Mental Health, and The University of Melbourne, Parkville, VIC, Australia
| | - Carlos M Opazo
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience & Mental Health, and The University of Melbourne, Parkville, VIC, Australia
| | - Benny Liberg
- Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - M Mallar Chakravarty
- Cerebral Imaging Center, Douglas Research Centre, Montreal, QC, Canada
- Department of Psychiatry, McGill University, Montreal, QC, Canada
- Department of Biomedical Engineering, McGill University, Montreal, QC, Canada
| | - Gabriel A Devenyi
- Cerebral Imaging Center, Douglas Research Centre, Montreal, QC, Canada
- Department of Psychiatry, McGill University, Montreal, QC, Canada
| | - Patricia Desmond
- Department of Radiology, Royal Melbourne Hospital, University of Melbourne, Parkville, VIC, Australia
| | - Vanessa L Cropley
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Carlton South, VIC, Australia
| | - Nikos Makris
- Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
- Center for Morphometric Analysis (CMA), Massachusetts General Hospital, Charlestown, MA, USA
| | - Martha E Shenton
- Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Ashley I Bush
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience & Mental Health, and The University of Melbourne, Parkville, VIC, Australia
| | - Dennis Velakoulis
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Carlton South, VIC, Australia
- Neuropsychiatry, The Royal Melbourne Hospital, Parkville, VIC, Australia
| | - Christos Pantelis
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Carlton South, VIC, Australia.
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia.
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Roddy DW, Roman E, Nasa A, Gazzaz A, Zainy A, Burke T, Staines L, Kelleher I, O'Neill A, Clarke M, O'Hanlon E, Cannon M. Microstructural changes along the cingulum in young adolescents with psychotic experiences: An along-tract analysis. Eur J Neurosci 2022; 56:5116-5131. [PMID: 36004608 PMCID: PMC9825926 DOI: 10.1111/ejn.15806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 07/30/2022] [Accepted: 08/18/2022] [Indexed: 01/11/2023]
Abstract
Psychotic experiences (PEs) such as hallucinations and delusions are common among young people without psychiatric diagnoses and are associated with connectivity and white matter abnormalities, particularly in the limbic system. Using diffusion magnetic resonance imaging (MRI) in adolescents with reported PEs and matched controls, we examined the cingulum white matter tract along its length rather than as the usually reported single indivisible structure. Complex regional differences in diffusion metrics were found along the bundle at key loci following Bonferroni significance adjustment (p < .00013) with moderate to large effect sizes (.11-.76) throughout all significant subsegments. In this prospective community-based cohort of school-age children, these findings suggest that white matter alterations in the limbic system may be more common in the general non-clinical adolescent population than previously thought. Such white matter alternations may only be uncovered using a similar more granular along-tract analysis of white matter tracts.
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Affiliation(s)
- Darren William Roddy
- Department of PsychiatryRoyal College of Surgeons in IrelandDublinIreland,Trinity College Institute of Neuroscience, Lloyd BuildingTrinity College DublinDublinIreland
| | - Elena Roman
- Department of PsychiatryRoyal College of Surgeons in IrelandDublinIreland
| | - Anurag Nasa
- Trinity College Institute of Neuroscience, Lloyd BuildingTrinity College DublinDublinIreland
| | - Areej Gazzaz
- Department of PsychiatryRoyal College of Surgeons in IrelandDublinIreland
| | - Ahmed Zainy
- Department of PsychiatryRoyal College of Surgeons in IrelandDublinIreland
| | - Tom Burke
- Department of PsychiatryRoyal College of Surgeons in IrelandDublinIreland
| | - Lorna Staines
- Department of PsychiatryRoyal College of Surgeons in IrelandDublinIreland
| | - Ian Kelleher
- Department of PsychiatryRoyal College of Surgeons in IrelandDublinIreland
| | - Aisling O'Neill
- Department of PsychiatryRoyal College of Surgeons in IrelandDublinIreland
| | - Mary Clarke
- Department of PsychiatryRoyal College of Surgeons in IrelandDublinIreland
| | - Erik O'Hanlon
- Department of PsychiatryRoyal College of Surgeons in IrelandDublinIreland,Trinity College Institute of Neuroscience, Lloyd BuildingTrinity College DublinDublinIreland
| | - Mary Cannon
- Department of PsychiatryRoyal College of Surgeons in IrelandDublinIreland
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7
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King VL, Lahti AC, Maximo JO, ver Hoef LW, John S, Kraguljac NV. Contrasting Frontoparietal Network Connectivity in Antipsychotic Medication-Naive First-Episode Psychosis Patients Who Do and Do Not Display Features of the Deficit Syndrome. Schizophr Bull 2022; 48:1344-1353. [PMID: 35869578 PMCID: PMC9673254 DOI: 10.1093/schbul/sbac081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND The deficit syndrome is a clinical subtype of schizophrenia that is characterized by enduring negative symptoms. Several lines of evidence point to frontoparietal involvement, but the frontoparietal control network (FPCN) and its subsystems (FPCNA and FPCNB) proposed by Yeo et al. have not been systematically characterized at rest in patients with the deficit syndrome. METHODS We used resting-state fMRI to investigate the FPCN and its subnetworks in 72 healthy controls and 65 antipsychotic medication-naive, first-episode psychosis patients (22 displayed deficit syndrome features, 43 did not). To assess whole-brain FPCN connectivity, we used the right posterior parietal cortex as the seed region. We then performed region of interest analyses in FPCN subsystems. RESULTS We found that patterns of FPCN dysconnectivity to the whole brain differed in patients who displayed deficit syndrome features compared with those who did not. Examining the FPCN on a more granular level revealed reduced within-FPCN(A) connectivity only in patients displaying deficit features. FPCNB connectivity did not differ between patient groups. DISCUSSION Here, we describe a neurobiological signature of aberrant FPCN connectivity in antipsychotic-naive, first-episode patients who display clinical features of the deficit syndrome. Importantly, frontoparietal subnetwork connectivity differentiated subgroups, where the FPCNA is selectively involved in patients with deficit features. Our findings add to the growing body of literature supporting a neurobiological distinction between two clinical subtypes of schizophrenia, which has the potential to be leveraged for patient stratification in clinical trials and the development of novel treatments.
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Affiliation(s)
- Victoria L King
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Adrienne C Lahti
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jose O Maximo
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Lawrence W ver Hoef
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Sooraj John
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Nina V Kraguljac
- To whom correspondence should be addressed; Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, SC 501, 1720 7th Ave S, Birmingham, AL 35294-0017, USA; tel: 205-996-7171, e-mail:
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8
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Palaniyappan L. Dissecting the neurobiology of linguistic disorganisation and impoverishment in schizophrenia. Semin Cell Dev Biol 2021; 129:47-60. [PMID: 34507903 DOI: 10.1016/j.semcdb.2021.08.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 08/13/2021] [Accepted: 05/06/2021] [Indexed: 12/16/2022]
Abstract
Schizophrenia provides a quintessential disease model of how disturbances in the molecular mechanisms of neurodevelopment lead to disruptions in the emergence of cognition. The central and often persistent feature of this illness is the disorganisation and impoverishment of language and related expressive behaviours. Though clinically more prominent, the periodic perceptual distortions characterised as psychosis are non-specific and often episodic. While several insights into psychosis have been gained based on study of the dopaminergic system, the mechanistic basis of linguistic disorganisation and impoverishment is still elusive. Key findings from cellular to systems-level studies highlight the role of ubiquitous, inhibitory processes in language production. Dysregulation of these processes at critical time periods, in key brain areas, provides a surprisingly parsimonious account of linguistic disorganisation and impoverishment in schizophrenia. This review links the notion of excitatory/inhibitory (E/I) imbalance at cortical microcircuits to the expression of language behaviour characteristic of schizophrenia, through the building blocks of neurochemistry, neurophysiology, and neurocognition.
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Affiliation(s)
- Lena Palaniyappan
- Department of Psychiatry,University of Western Ontario, London, Ontario, Canada; Robarts Research Institute,University of Western Ontario, London, Ontario, Canada; Lawson Health Research Institute, London, Ontario, Canada.
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9
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Kraguljac NV, McDonald WM, Widge AS, Rodriguez CI, Tohen M, Nemeroff CB. Neuroimaging Biomarkers in Schizophrenia. Am J Psychiatry 2021; 178:509-521. [PMID: 33397140 PMCID: PMC8222104 DOI: 10.1176/appi.ajp.2020.20030340] [Citation(s) in RCA: 114] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Schizophrenia is a complex neuropsychiatric syndrome with a heterogeneous genetic, neurobiological, and phenotypic profile. Currently, no objective biological measures-that is, biomarkers-are available to inform diagnostic or treatment decisions. Neuroimaging is well positioned for biomarker development in schizophrenia, as it may capture phenotypic variations in molecular and cellular disease targets, or in brain circuits. These mechanistically based biomarkers may represent a direct measure of the pathophysiological underpinnings of the disease process and thus could serve as true intermediate or surrogate endpoints. Effective biomarkers could validate new treatment targets or pathways, predict response, aid in selection of patients for therapy, determine treatment regimens, and provide a rationale for personalized treatments. In this review, the authors discuss a range of mechanistically plausible neuroimaging biomarker candidates, including dopamine hyperactivity, N-methyl-d-aspartate receptor hypofunction, hippocampal hyperactivity, immune dysregulation, dysconnectivity, and cortical gray matter volume loss. They then focus on the putative neuroimaging biomarkers for disease risk, diagnosis, target engagement, and treatment response in schizophrenia. Finally, they highlight areas of unmet need and discuss strategies to advance biomarker development.
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Affiliation(s)
- Nina V. Kraguljac
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL,Corresponding Author: Nina Vanessa Kraguljac, MD, Department of Psychiatry and Behavioral Neurobiology, The University of Alabama at Birmingham, SC 501, 1720 7th Ave S, Birmingham, AL 35294-0017, 205-996-7171,
| | - William M. McDonald
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine
| | - Alik S. Widge
- Department of Psychiatry and Behavioral Sciences, University of Minnesota, Minneapolis, MN
| | - Carolyn I. Rodriguez
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA,Veterans Affairs Palo Alto Health Care System, Palo Alto, CA
| | - Mauricio Tohen
- Department of Psychiatry and Behavioral Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM, USA
| | - Charles B. Nemeroff
- Department of Psychiatry, University of Texas Dell Medical School, Austin, TX
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10
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Ver Hoef L, Deshpande H, Cure J, Selladurai G, Beattie J, Kennedy RE, Knowlton RC, Szaflarski JP. Clear and Consistent Imaging of Hippocampal Internal Architecture With High Resolution Multiple Image Co-registration and Averaging (HR-MICRA). Front Neurosci 2021; 15:546312. [PMID: 33642971 PMCID: PMC7905096 DOI: 10.3389/fnins.2021.546312] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 01/20/2021] [Indexed: 11/14/2022] Open
Abstract
Magnetic resonance imaging of hippocampal internal architecture (HIA) at 3T is challenging. HIA is defined by layers of gray and white matter that are less than 1 mm thick in the coronal plane. To visualize HIA, conventional MRI approaches have relied on sequences with high in-plane resolution (≤0.5 mm) but comparatively thick slices (2–5 mm). However, thicker slices are prone to volume averaging effects that result in loss of HIA clarity and blurring of the borders of the hippocampal subfields in up to 61% of slices as has been reported. In this work we describe an approach to hippocampal imaging that provides consistently high HIA clarity using a commonly available sequence and post-processing techniques that is flexible and may be applicable to any MRI platform. We refer to this approach as High Resolution Multiple Image Co-registration and Averaging (HR-MICRA). This approach uses a variable flip angle turbo spin echo sequence to repeatedly acquire a whole brain T2w image volume with high resolution in three dimensions in a relatively short amount of time, and then co-register the volumes to correct for movement and average the repeated scans to improve SNR. We compared the averages of 4, 9, and 16 individual scans in 20 healthy controls using a published HIA clarity rating scale. In the body of the hippocampus, the proportion of slices with good or excellent HIA clarity was 90%, 83%, and 67% for the 16x, 9x, and 4x HR-MICRA images, respectively. Using the 4x HR-MICRA images as a baseline, the 9x HR-MICRA images were 2.6 times and 16x HR-MICRA images were 3.2 times more likely to have high HIA ratings (p < 0.001) across all hippocampal segments (head, body, and tail). The thin slices of the HR-MICRA images allow reformatting in any plane with clear visualization of hippocampal dentation in the sagittal plane. Clear and consistent visualization of HIA will allow application of this technique to future hippocampal structure research, as well as more precise manual or automated segmentation.
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Affiliation(s)
- Lawrence Ver Hoef
- Department of Neurology, The University of Alabama at Birmingham, Birmingham, AL, United States.,Department of Biomedical Engineering, The University of Alabama at Birmingham, Birmingham, AL, United States.,Neurology Service, Birmingham VA Medical Center, Birmingham, AL, United States
| | - Hrishikesh Deshpande
- Department of Radiology, The University of Alabama at Birmingham, Birmingham, AL, United States
| | - Joel Cure
- Department of Radiology, The University of Alabama at Birmingham, Birmingham, AL, United States
| | - Goutham Selladurai
- Department of Neurology, The University of Alabama at Birmingham, Birmingham, AL, United States
| | - Julia Beattie
- Division of Behavioral Medicine and Clinical Psychology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - Richard E Kennedy
- Division of Gerontology, Geriatrics, and Palliative Care, Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL, United States
| | - Robert C Knowlton
- Department of Neurology, University of California, San Francisco, San Francisco, CA, United States
| | - Jerzy P Szaflarski
- Department of Neurology, The University of Alabama at Birmingham, Birmingham, AL, United States
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11
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Curtis MT, Coffman BA, Salisbury DF. Parahippocampal area three gray matter is reduced in first-episode schizophrenia spectrum: Discovery and replication samples. Hum Brain Mapp 2020; 42:724-736. [PMID: 33219733 PMCID: PMC7814759 DOI: 10.1002/hbm.25256] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 09/02/2020] [Accepted: 10/07/2020] [Indexed: 12/27/2022] Open
Abstract
Early course schizophrenia is associated with reduced gray matter. The specific structures affected first and how deficits impact symptoms and cognition remain unresolved. We used the Human Connectome Project multimodal parcellation (HCP‐MMP) to precisely identify cortical areas and investigate thickness abnormalities in discovery and replication samples of first‐episode schizophrenia spectrum individuals (FESz). In the discovery sample, T1w scans were acquired from 31 FESz and 31 matched healthy controls (HC). Thickness was calculated for 360 regions in Freesurfer. In the replication sample, high‐resolution T1w, T2w, and BOLD‐rest scans were acquired from 23 FESz and 32 HC and processed with HCP protocols. Thickness was calculated for regions significant in the discovery sample. After FDR correction (q < .05), left and right parahippocampal area 3 (PHA3) were significantly thinner in FESz. In the replication sample, bilateral PHA3 were again thinner in FESz (q < .05). Exploratory correlation analyses revealed left PHA3 was positively associated with hallucinations and right PHA3 was positively associated with processing speed, working memory, and verbal learning. The novel use of the HCP‐MMP in two independent FESz samples revealed thinner bilateral PHA3, suggesting this byway between cortical and limbic processing is a critical site of pathology near the emergence of psychosis.
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Affiliation(s)
- Mark T Curtis
- Clinical Neurophysiology Research Laboratory, Western Psychiatric Hospital, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Brian A Coffman
- Clinical Neurophysiology Research Laboratory, Western Psychiatric Hospital, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Dean F Salisbury
- Clinical Neurophysiology Research Laboratory, Western Psychiatric Hospital, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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12
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Arjmand S, Kohlmeier KA, Behzadi M, Ilaghi M, Mazhari S, Shabani M. Looking into a Deluded Brain through a Neuroimaging Lens. Neuroscientist 2020; 27:73-87. [PMID: 32648532 DOI: 10.1177/1073858420936172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Delusions are irrational, tenacious, and incorrigible false beliefs that are the most common symptom of a range of brain disorders including schizophrenia, Alzheimer's, and Parkinson's disease. In the case of schizophrenia and other primary delusional disorders, their appearance is often how the disorder is first detected and can be sufficient for diagnosis. At this time, not much is known about the brain dysfunctions leading to delusions, and hindering our understanding is that the complexity of the nature of delusions, and their very unique relevance to the human experience has hampered elucidation of their underlying neurobiology using either patients or animal models. Advances in neuroimaging along with improved psychiatric and cognitive modeling offers us a new opportunity to look with more investigative power into the deluded brain. In this article, based on data obtained from neuroimaging studies, we have attempted to draw a picture of the neural networks involved when delusion is present and evaluate whether different manifestations of delusions engage different regions of the brain.
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Affiliation(s)
- Shokouh Arjmand
- Institute of Neuropharmacology, Kerman Neuroscience Research Center, Kerman University of Medical Sciences, Kerman, Iran
| | - Kristi A Kohlmeier
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mina Behzadi
- Institute of Neuropharmacology, Kerman Neuroscience Research Center, Kerman University of Medical Sciences, Kerman, Iran
| | - Mehran Ilaghi
- Institute of Neuropharmacology, Kerman Neuroscience Research Center, Kerman University of Medical Sciences, Kerman, Iran
| | - Shahrzad Mazhari
- Institute of Neuropharmacology, Kerman Neuroscience Research Center, Kerman University of Medical Sciences, Kerman, Iran.,Department of Psychiatry, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Mohammad Shabani
- Institute of Neuropharmacology, Kerman Neuroscience Research Center, Kerman University of Medical Sciences, Kerman, Iran
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13
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Aberrant salience predicts psychotic-like experiences in daily life: An experience sampling study. Schizophr Res 2020; 220:218-224. [PMID: 32249121 DOI: 10.1016/j.schres.2020.03.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 02/28/2020] [Accepted: 03/08/2020] [Indexed: 01/09/2023]
Abstract
Individuals at risk for schizophrenia-spectrum disorders tend to make atypical attributions of significance to unimportant stimuli. This experience of heightened significance, known as aberrant salience, is thought to contribute to psychotic symptoms. The Aberrant Salience Inventory (ASI) was designed to capture subclinical and clinical manifestations of the construct, and scores on the scale are associated with schizophrenia-like symptoms and behaviors in laboratory studies. Experience sampling methodology (ESM) studies have assessed momentary experiences of aberrant salience in daily life, but to our knowledge no study has examined real-world outcomes using the ASI as a trait measure of aberrant salience. The current study assessed the expression of aberrant salience in undergraduates oversampled for positive and negative schizotypy using ESM. Overall, findings of the expression of aberrant salience in daily life were similar to previous findings with positive schizotypy. Aberrant salience was associated with psychotic-like and disorganized symptoms, suspiciousness, and social impairment in daily life. It was unassociated with negative symptoms, stress, or affect in the moment. Aberrant salience did not moderate daily life associations of stress with schizotypic symptoms. The ASI subscales showed differential patterns of associations in daily life. These findings support the construct validity of the ASI and suggest that aberrant salience traits are relevant for real-world outcomes in schizotypy-spectrum psychopathology.
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14
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Segev A, Yanagi M, Scott D, Southcott SA, Lister JM, Tan C, Li W, Birnbaum SG, Kourrich S, Tamminga CA. Reduced GluN1 in mouse dentate gyrus is associated with CA3 hyperactivity and psychosis-like behaviors. Mol Psychiatry 2020; 25:2832-2843. [PMID: 30038231 PMCID: PMC6344327 DOI: 10.1038/s41380-018-0124-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 10/30/2017] [Accepted: 01/15/2018] [Indexed: 01/07/2023]
Abstract
Recent findings from in vivo-imaging and human post-mortem tissue studies in schizophrenic psychosis (SzP), have demonstrated functional and molecular changes in hippocampal subfields that can be associated with hippocampal hyperexcitability. In this study, we used a subfield-specific GluN1 knockout mouse with a disease-like molecular perturbation expressed only in hippocampal dentate gyrus (DG) and assessed its association with hippocampal physiology and psychosis-like behaviors. First, we used whole-cell patch-clamp recordings to measure the physiological changes in hippocampal subfields and cFos immunohistochemistry to examine cellular excitability. DG-GluN1 KO mice show CA3 cellular hyperactivity, detected using two approaches: (1) increased excitatory glutamate transmission at mossy fibers (MF)-CA3 synapses, and (2) an increased number of cFos-activated pyramidal neurons in CA3, an outcome that appears to project downstream to CA1 and basolateral amygdala (BLA). Furthermore, we examined psychosis-like behaviors and pathological memory processing; these show an increase in fear conditioning (FC), a reduction in prepulse inhibition (PPI) in the KO animal, along with a deterioration in memory accuracy with Morris Water Maze (MWM) and reduced social memory (SM). Moreover, with DREADD vectors, we demonstrate a remarkably similar behavioral profile when we induce CA3 hyperactivity. These hippocampal subfield changes could provide the basis for the observed increase in human hippocampal activity in SzP, based on the shared DG-specific GluN1 reduction. With further characterization, these animal model systems may serve as targets to test psychosis mechanisms related to hippocampus and assess potential hippocampus-directed treatments.
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Affiliation(s)
- Amir Segev
- grid.267313.20000 0000 9482 7121Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX 75390 USA
| | - Masaya Yanagi
- grid.267313.20000 0000 9482 7121Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX 75390 USA ,grid.258622.90000 0004 1936 9967Present Address: Department of Neuropsychiatry, Kindai University Faculty of Medicine, Osaka, Japan
| | - Daniel Scott
- grid.267313.20000 0000 9482 7121Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX 75390 USA
| | - Sarah A. Southcott
- grid.267313.20000 0000 9482 7121Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX 75390 USA
| | - Jacob M. Lister
- grid.267313.20000 0000 9482 7121Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX 75390 USA ,grid.47100.320000000419368710Yale University, School of Medicine, 333 Cedar Street, New Haven, CT 06510 USA ,grid.47100.320000000419368710Present Address: Yale University, School of Medicine, New Haven, CT USA
| | - Chunfeng Tan
- grid.267313.20000 0000 9482 7121Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX 75390 USA
| | - Wei Li
- grid.267313.20000 0000 9482 7121Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX 75390 USA
| | - Shari G. Birnbaum
- grid.267313.20000 0000 9482 7121Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX 75390 USA
| | - Saïd Kourrich
- Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX, 75390, USA.
| | - Carol A. Tamminga
- grid.267313.20000 0000 9482 7121Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX 75390 USA
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15
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Vanes LD, Mouchlianitis E, Patel K, Barry E, Wong K, Thomas M, Szentgyorgyi T, Joyce D, Shergill S. Neural correlates of positive and negative symptoms through the illness course: an fMRI study in early psychosis and chronic schizophrenia. Sci Rep 2019; 9:14444. [PMID: 31595009 PMCID: PMC6783468 DOI: 10.1038/s41598-019-51023-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 09/23/2019] [Indexed: 12/14/2022] Open
Abstract
Psychotic illness is associated with cognitive control deficits and abnormal recruitment of neural circuits subserving cognitive control. It is unclear to what extent this dysfunction underlies the development and/or maintenance of positive and negative symptoms typically observed in schizophrenia. In this study we compared fMRI activation on a standard Stroop task and its relationship with positive and negative symptoms in early psychosis (EP, N = 88) and chronic schizophrenia (CHR-SZ, N = 38) patients. CHR-SZ patients showed reduced frontal, striatal, and parietal activation across incongruent and congruent trials compared to EP patients. Higher positive symptom severity was associated with reduced activation across both trial types in supplementary motor area (SMA), middle temporal gyrus and cerebellum in EP, but not CHR-SZ patients. Higher negative symptom severity was associated with reduced cerebellar activation in EP, but not in CHR-SZ patients. A negative correlation between negative symptoms and activation in SMA and precentral gyrus was observed in EP patients and in CHR-SZ patients. The results suggest that the neural substrate of positive symptoms changes with illness chronicity, and that cognitive control related neural circuits may be most relevant in the initial development phase of positive symptoms. These findings also highlight a changing role for the cerebellum in the development and later maintenance of both positive and negative symptoms.
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Affiliation(s)
- Lucy D Vanes
- Wellcome Centre for Human Neuroimaging, University College London, 12 Queen Square, London, WC1N 3AR, United Kingdom.
| | - Elias Mouchlianitis
- Institute of Psychiatry, Psychology and Neuroscience, de Crespigny Park, London, SE5 8AF, United Kingdom
| | - Krisna Patel
- Institute of Psychiatry, Psychology and Neuroscience, de Crespigny Park, London, SE5 8AF, United Kingdom
| | - Erica Barry
- Institute Department of Clinical Sciences, Cornell University College of Veterinary Medicine, Ithaca, NY, USA
| | - Katie Wong
- Institute of Psychiatry, Psychology and Neuroscience, de Crespigny Park, London, SE5 8AF, United Kingdom
| | - Megan Thomas
- Institute of Psychiatry, Psychology and Neuroscience, de Crespigny Park, London, SE5 8AF, United Kingdom
| | - Timea Szentgyorgyi
- Institute of Psychiatry, Psychology and Neuroscience, de Crespigny Park, London, SE5 8AF, United Kingdom
| | - Dan Joyce
- Institute of Psychiatry, Psychology and Neuroscience, de Crespigny Park, London, SE5 8AF, United Kingdom
| | - Sukhwinder Shergill
- Institute of Psychiatry, Psychology and Neuroscience, de Crespigny Park, London, SE5 8AF, United Kingdom
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16
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Bryant JE, Frölich M, Tran S, Reid MA, Lahti AC, Kraguljac NV. Ketamine induced changes in regional cerebral blood flow, interregional connectivity patterns, and glutamate metabolism. J Psychiatr Res 2019; 117:108-115. [PMID: 31376621 PMCID: PMC7291620 DOI: 10.1016/j.jpsychires.2019.07.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 06/19/2019] [Accepted: 07/26/2019] [Indexed: 12/31/2022]
Abstract
Several imaging studies have attempted to characterize the contribution of glutamatergic dysfunction to functional dysconnectivity of large-scale brain networks using ketamine models. However, findings from BOLD imaging studies are conflicting, in part because the signal stems from a complex interaction between blood flow, blood volume, and oxygen consumption. We used arterial spin labelling imaging to measure regional cerebral blood flow (rCBF) in a group of healthy volunteers during a saline and during a ketamine infusion. We examined changes in rCBF and interregional connectivity patterns, as well as their associations with clinical symptom severity and Glx (glutamate + glutamine) assessed with magnetic resonance spectroscopy. We report a regionally selective pattern of rCBF changes following ketamine administration and complex changes in interregional connectivity patterns. We also found that the increase in rCBF in the bilateral putamen and left hippocampus was positively correlated with ketamine induced clinical symptom severity while anterior cingulate rCBF during the ketamine challenge was negatively correlated with change in hippocampal Glx. Our study adds to the efforts to empirically confirm putative links between an NMDA receptor blockage and dysconnectivity of large-scale brain networks, specifically the salience, executive control and default mode networks, suggesting that a glutamatergic imbalance may contribute to dysconnectivity. Development of glutamatergic compounds that alleviate disease burden, possibly through normalizing glutamate excess related increased rCBF, is direly needed.
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Affiliation(s)
- James Edward Bryant
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, United States
| | - Michael Frölich
- Department of Anesthesiology, University of Alabama at Birmingham, United States
| | - Steve Tran
- Department of Anesthesiology, University of Alabama at Birmingham, United States
| | - Meredith Amanda Reid
- MRI Research Center, Department of Electrical and Computer Engineering, Auburn University, United States
| | - Adrienne Carol Lahti
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, United States
| | - Nina Vanessa Kraguljac
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, United States.
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17
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Kraguljac NV, Morgan CJ, Reid MA, White DM, Jindal RD, Sivaraman S, Martinak BK, Lahti AC. A longitudinal magnetic resonance spectroscopy study investigating effects of risperidone in the anterior cingulate cortex and hippocampus in schizophrenia. Schizophr Res 2019; 210:239-244. [PMID: 30630705 PMCID: PMC7881837 DOI: 10.1016/j.schres.2018.12.028] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 12/18/2018] [Accepted: 12/19/2018] [Indexed: 12/30/2022]
Abstract
Magnetic Resonance Spectroscopy is a popular approach to probe brain chemistry in schizophrenia (SZ), but no consensus exists as to the extent of alterations. This may be attributable to differential effects of populations studied, brain regions examined, or antipsychotic medication effects. Here, we measured neurometabolites in the anterior cingulate cortex (ACC) and hippocampus, two structurally dissimilar brain regions implicated in the SZ pathophysiology. We enrolled 61 SZ with the goal to scan them before and after six weeks of treatment with risperidone. We also scanned 31 matched healthy controls twice, six weeks apart. Using mixed effect repeated measures linear models to examine the effect of group and time on metabolite levels in each voxel, we report an increase in hippocampal glutamate + glutamine (Glx) in SZ compared to controls (p = 0.043), but no effect of antipsychotic medication (p = 0.330). In the ACC, we did not find metabolite alterations or antipsychotic medication related changes after six weeks of treatment with risperidone. The coefficients for the discriminant function (differentiating SZ from HC) in the ACC were greatest for NAA (-0.83), and in the hippocampus for Glx (0.76), the same metabolites were associated with greater treatment response in patients at trend level. Taken together, our data extends the existing literature by demonstrating regionally distinct metabolite alterations in the same patient group and suggests that antipsychotic medications may have limited effects on metabolite levels in these regions.
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Affiliation(s)
- Nina V. Kraguljac
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham
| | | | - Meredith A. Reid
- MRI Research Center, Department of Electrical and Computer Engineering, Auburn University
| | - David M. White
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham
| | - Ripu D. Jindal
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham,Department of Neurology, Birmingham VA Medical Center
| | - Soumya Sivaraman
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham
| | - Bridgette K. Martinak
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham
| | - Adrienne C. Lahti
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham
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18
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Schneider K, Michels L, Hartmann-Riemer MN, Burrer A, Tobler PN, Stämpfli P, Kirschner M, Seifritz E, Kaiser S. Cerebral blood flow in striatal regions is associated with apathy in patients with schizophrenia. J Psychiatry Neurosci 2019; 44:102-110. [PMID: 30246686 PMCID: PMC6397041 DOI: 10.1503/jpn.170150] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Striatal dysfunction has been proposed as a pathomechanism for negative symptoms in schizophrenia. There is consensus that negative symptoms can be grouped into 2 dimensions: apathy and diminished expression. Recent studies suggest that different neural mechanisms underlie these dimensions, but the relationship between regional resting-state cerebral blood flow (rCBF) and negative symptom dimensions has not been investigated. METHODS This study included 29 patients with schizophrenia and 20 healthy controls. We measured rCBF in the striatum using arterial spin labelling (ASL) MRI. We assessed negative symptoms using the Brief Negative Symptom Scale. RESULTS In the ventral and dorsal striatum, rCBF was not different between patients with schizophrenia and controls. However, we did find a positive association between the severity of apathy and increased rCBF in the ventral and dorsal striatum in patients with schizophrenia. This effect was not present for diminished expression. LIMITATIONS All patients were taking atypical antipsychotics, so an effect of antipsychotic medication on rCBF could not be excluded, although we did not find a significant association between rCBF and chlorpromazine equivalents. CONCLUSION The main finding of this study was a specific association between increased striatal rCBF and the negative symptom dimension of apathy. Our results further support the separate assessment of apathy and diminished expression when investigating the neural basis of negative symptoms. The ASL technique can provide a direct and quantitative approach to investigating the role of rCBF changes in the pathophysiology of negative symptoms.
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Affiliation(s)
- Karoline Schneider
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich (Schneider, Hartmann-Riemer, Burrer, Stämpfli, Kirschner, Seifritz); Institute of Neuroradiology, University Hospital Zurich (Michels); Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich (Hartmann-Riemer, Tobler); MR Center of the Psychiatric University Hospital and the Department of Child and Adolescent Psychiatry, University of Zurich (Stämpfli); and the Adult Psychiatry Division, Department of Mental Health and Psychiatry, Geneva University Hospitals (Kaiser)
| | - Lars Michels
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich (Schneider, Hartmann-Riemer, Burrer, Stämpfli, Kirschner, Seifritz); Institute of Neuroradiology, University Hospital Zurich (Michels); Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich (Hartmann-Riemer, Tobler); MR Center of the Psychiatric University Hospital and the Department of Child and Adolescent Psychiatry, University of Zurich (Stämpfli); and the Adult Psychiatry Division, Department of Mental Health and Psychiatry, Geneva University Hospitals (Kaiser)
| | - Matthias N Hartmann-Riemer
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich (Schneider, Hartmann-Riemer, Burrer, Stämpfli, Kirschner, Seifritz); Institute of Neuroradiology, University Hospital Zurich (Michels); Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich (Hartmann-Riemer, Tobler); MR Center of the Psychiatric University Hospital and the Department of Child and Adolescent Psychiatry, University of Zurich (Stämpfli); and the Adult Psychiatry Division, Department of Mental Health and Psychiatry, Geneva University Hospitals (Kaiser)
| | - Achim Burrer
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich (Schneider, Hartmann-Riemer, Burrer, Stämpfli, Kirschner, Seifritz); Institute of Neuroradiology, University Hospital Zurich (Michels); Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich (Hartmann-Riemer, Tobler); MR Center of the Psychiatric University Hospital and the Department of Child and Adolescent Psychiatry, University of Zurich (Stämpfli); and the Adult Psychiatry Division, Department of Mental Health and Psychiatry, Geneva University Hospitals (Kaiser)
| | - Philippe N Tobler
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich (Schneider, Hartmann-Riemer, Burrer, Stämpfli, Kirschner, Seifritz); Institute of Neuroradiology, University Hospital Zurich (Michels); Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich (Hartmann-Riemer, Tobler); MR Center of the Psychiatric University Hospital and the Department of Child and Adolescent Psychiatry, University of Zurich (Stämpfli); and the Adult Psychiatry Division, Department of Mental Health and Psychiatry, Geneva University Hospitals (Kaiser)
| | - Philipp Stämpfli
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich (Schneider, Hartmann-Riemer, Burrer, Stämpfli, Kirschner, Seifritz); Institute of Neuroradiology, University Hospital Zurich (Michels); Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich (Hartmann-Riemer, Tobler); MR Center of the Psychiatric University Hospital and the Department of Child and Adolescent Psychiatry, University of Zurich (Stämpfli); and the Adult Psychiatry Division, Department of Mental Health and Psychiatry, Geneva University Hospitals (Kaiser)
| | - Matthias Kirschner
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich (Schneider, Hartmann-Riemer, Burrer, Stämpfli, Kirschner, Seifritz); Institute of Neuroradiology, University Hospital Zurich (Michels); Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich (Hartmann-Riemer, Tobler); MR Center of the Psychiatric University Hospital and the Department of Child and Adolescent Psychiatry, University of Zurich (Stämpfli); and the Adult Psychiatry Division, Department of Mental Health and Psychiatry, Geneva University Hospitals (Kaiser)
| | - Erich Seifritz
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich (Schneider, Hartmann-Riemer, Burrer, Stämpfli, Kirschner, Seifritz); Institute of Neuroradiology, University Hospital Zurich (Michels); Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich (Hartmann-Riemer, Tobler); MR Center of the Psychiatric University Hospital and the Department of Child and Adolescent Psychiatry, University of Zurich (Stämpfli); and the Adult Psychiatry Division, Department of Mental Health and Psychiatry, Geneva University Hospitals (Kaiser)
| | - Stefan Kaiser
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich (Schneider, Hartmann-Riemer, Burrer, Stämpfli, Kirschner, Seifritz); Institute of Neuroradiology, University Hospital Zurich (Michels); Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich (Hartmann-Riemer, Tobler); MR Center of the Psychiatric University Hospital and the Department of Child and Adolescent Psychiatry, University of Zurich (Stämpfli); and the Adult Psychiatry Division, Department of Mental Health and Psychiatry, Geneva University Hospitals (Kaiser)
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Supekar K, Cai W, Krishnadas R, Palaniyappan L, Menon V. Dysregulated Brain Dynamics in a Triple-Network Saliency Model of Schizophrenia and Its Relation to Psychosis. Biol Psychiatry 2019; 85:60-69. [PMID: 30177256 DOI: 10.1016/j.biopsych.2018.07.020] [Citation(s) in RCA: 125] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 07/08/2018] [Accepted: 07/09/2018] [Indexed: 12/18/2022]
Abstract
BACKGROUND Schizophrenia is a highly disabling psychiatric disorder characterized by a range of positive "psychosis" symptoms. However, the neurobiology of psychosis and associated systems-level disruptions in the brain remain poorly understood. Here, we test an aberrant saliency model of psychosis, which posits that dysregulated dynamic cross-network interactions among the salience network (SN), central executive network, and default mode network contribute to positive symptoms in patients with schizophrenia. METHODS Using task-free functional magnetic resonance imaging data from two independent cohorts, we examined 1) dynamic time-varying cross-network interactions among the SN, central executive network, and default mode network in 130 patients with schizophrenia versus well-matched control subjects; 2) accuracy of a saliency model-based classifier for distinguishing dynamic brain network interactions in patients versus control subjects; and 3) the relation between SN-centered network dynamics and clinical symptoms. RESULTS In both cohorts, we found that dynamic SN-centered cross-network interactions were significantly reduced, less persistent, and more variable in patients with schizophrenia compared with control subjects. Multivariate classification analysis identified dynamic SN-centered cross-network interaction patterns as factors that distinguish patients from control subjects, with accuracies of 78% and 80% in the two cohorts, respectively. Crucially, in both cohorts, dynamic time-varying measures of SN-centered cross-network interactions were correlated with positive, but not negative, symptoms. CONCLUSIONS Aberrations in time-varying engagement of the SN with the central executive network and default mode network is a clinically relevant neurobiological signature of psychosis in schizophrenia. Our findings provide strong evidence for dysregulated brain dynamics in a triple-network saliency model of schizophrenia and inform theoretically motivated systems neuroscience approaches for characterizing aberrant brain dynamics associated with psychosis.
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Affiliation(s)
- Kaustubh Supekar
- Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, California.
| | - Weidong Cai
- Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, California
| | - Rajeev Krishnadas
- Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Sackler Institute of Psychobiological Research, University of Glasgow, United Kingdom
| | - Lena Palaniyappan
- Department of Psychiatry and Robarts Research Institute, University of Western Ontario, London, Ontario, Canada; Lawson Health Research Institute, London, Ontario, Canada
| | - Vinod Menon
- Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Department of Neurology & Neurological Sciences, Stanford University School of Medicine, Stanford, California; Stanford Neurosciences Institute, Stanford University School of Medicine, Stanford, California.
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20
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Reid MA, Salibi N, White DM, Gawne TJ, Denney TS, Lahti AC. 7T Proton Magnetic Resonance Spectroscopy of the Anterior Cingulate Cortex in First-Episode Schizophrenia. Schizophr Bull 2019; 45:180-189. [PMID: 29385594 PMCID: PMC6293230 DOI: 10.1093/schbul/sbx190] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Recent magnetic resonance spectroscopy (MRS) studies suggest that abnormalities of the glutamatergic system in schizophrenia may be dependent on illness stage, medication status, and symptomatology. Glutamatergic metabolites appear to be elevated in the prodromal and early stages of schizophrenia but unchanged or reduced below normal in chronic, medicated patients. However, few of these studies have measured metabolites with high-field 7T MR scanners, which offer higher signal-to-noise ratio and better spectral resolution than 3T scanners and facilitate separation of glutamate and glutamine into distinct signals. In this study, we examined glutamate and other metabolites in the dorsal anterior cingulate cortex (ACC) of first-episode schizophrenia patients. Glutamate and N-acetylaspartate (NAA) were significantly lower in schizophrenia patients vs controls. No differences were observed in levels of glutamine, GABA, or other metabolites. In schizophrenia patients but not controls, GABA was negatively correlated with the total score on the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) as well as the immediate memory and language subscales. Our findings suggest that glutamate and NAA reductions in the ACC may be present early in the illness, but additional large-scale studies are needed to confirm these results as well as longitudinal studies to determine the effect of illness progression and treatment. The correlation between GABA and cognitive function suggests that MRS may be an important technique for investigating the neurobiology underlying cognitive deficits in schizophrenia.
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Affiliation(s)
- Meredith A Reid
- AU MRI Research Center, Department of Electrical & Computer Engineering, Auburn University
| | | | - David M White
- Department of Psychiatry and Behavioral Neurobiology, The University of Alabama at Birmingham
| | - Timothy J Gawne
- Department of Vision Sciences, The University of Alabama at Birmingham
| | - Thomas S Denney
- AU MRI Research Center, Department of Electrical & Computer Engineering, Auburn University
| | - Adrienne C Lahti
- Department of Psychiatry and Behavioral Neurobiology, The University of Alabama at Birmingham,To whom correspondence should be addressed; Department of Psychiatry and Behavioral Neurobiology, The University of Alabama at Birmingham, SC 501, 1720 2 Ave S, Birmingham, AL 35294-0017, US; tel: 205-996-6776, fax: 205-975-4879, e-mail:
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21
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Liemburg EJ, Nolte IM, Klein HC, Knegtering H. Relation of inflammatory markers with symptoms of psychotic disorders: a large cohort study. Prog Neuropsychopharmacol Biol Psychiatry 2018; 86:89-94. [PMID: 29778547 DOI: 10.1016/j.pnpbp.2018.04.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 04/06/2018] [Accepted: 04/16/2018] [Indexed: 12/13/2022]
Abstract
AIMS Immunological mechanisms may play a role in symptomatology of patients with a psychotic disorder. Besides metabolic problems and medication use, inflammatory processes that may occur due to the disorder may cause increased inflammatory markers and concurrent psychiatric symptoms. The aim of this study is to investigate whether levels of C-reactive protein (CRP) and white blood cell count (WBC) are related to positive and negative symptoms of psychotic disorders, and whether age, gender, duration of illness, smoking behavior, haloperidol equivalents, mediation use, body mass, and metabolic syndrome affect this relation. METHODS CRP and WBC values of 2123 patients with a psychotic disorder were related to positive and negative symptoms measured with a psychiatric interview. CRP was analyzed by survival analysis accounting for detection limit and WBC by linear mixed model analysis. In case of a significant association, the confounding factors were added to the model. RESULTS Both WBC and CRP were related to both positive and negative symptoms, even after correction for age, gender, smoking, use of medication and metabolic problems. Of the covariates, gender, metabolic problems, smoking and statins also showed a strong association with inflammatory markers. CONCLUSIONS This study in a large patient-group confirmed that inflammatory markers are related to psychotic disorders, particularly negative symptoms. Future studies could use more precise measures of inflammatory markers and measure symptomatic state at specific moments in illness progression.
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Affiliation(s)
- E J Liemburg
- University of Groningen, University Medical Center Groningen, University Center for Psychiatry, PO Box 30001, 9700, RB, Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Rob Giel Research Center, Hanzeplein 1 (CC72), 9713, GZ, Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Department of Neuroscience, BCN Neuroimaging Center, Antonius Deusinglaan 2 (FA32), 9713, AW, Groningen, The Netherlands.
| | - I M Nolte
- University of Groningen, University Medical Center Groningen, Department of Epidemiology, PO Box 30001, 9700, RB, Groningen, The Netherlands.
| | | | - H C Klein
- University of Groningen, University Medical Center Groningen, University Center for Psychiatry, PO Box 30001, 9700, RB, Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, PO Box 30001, 9700, RB, Groningen, The Netherlands.
| | - H Knegtering
- University of Groningen, University Medical Center Groningen, Rob Giel Research Center, Hanzeplein 1 (CC72), 9713, GZ, Groningen, The Netherlands; Lentis Mental Health Organization, Lentis Research, Hereweg 80, 9725, AG, Groningen, The Netherlands.
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22
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Strik W, Stegmayer K, Walther S, Dierks T. Systems Neuroscience of Psychosis: Mapping Schizophrenia Symptoms onto Brain Systems. Neuropsychobiology 2018; 75:100-116. [PMID: 29258073 DOI: 10.1159/000485221] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Schizophrenia research has been in a deadlock for many decades. Despite important advances in clinical treatment, there are still major concerns regarding long-term psychosocial reintegration and disease management, biological heterogeneity, unsatisfactory predictors of individual course and treatment strategies, and a confusing variety of controversial theories about its etiology and pathophysiological mechanisms. In the present perspective on schizophrenia research, we first discuss a methodological pitfall in contemporary schizophrenia research inherent in the attempt to link mental phenomena with the brain: we claim that the time-honored phenomenological method of defining mental symptoms should not be contaminated with the naturalistic approach of modern neuroscience. We then describe our Systems Neuroscience of Psychosis (SyNoPsis) project, which aims to overcome this intrinsic problem of psychiatric research. Considering schizophrenia primarily as a disorder of interindividual communication, we developed a neurobiologically informed semiotics of psychotic disorders, as well as an operational clinical rating scale. The novel psychopathology allows disentangling the clinical manifestations of schizophrenia into behavioral domains matching the functions of three well-described higher-order corticobasal brain systems involved in interindividual human communication, namely, the limbic, associative, and motor loops, including their corticocortical sensorimotor connections. The results of several empirical studies support the hypothesis that the proposed three-dimensional symptom structure, segregated into the affective, the language, and the motor domain, can be specifically mapped onto structural and functional abnormalities of the respective brain systems. New pathophysiological hypotheses derived from this brain system-oriented approach have helped to develop and improve novel treatment strategies with noninvasive brain stimulation and practicable clinical parameters. In clinical practice, the novel psychopathology allows confining the communication deficits of the individual patient, shifting attention from the symptoms to the intact resources. We have studied this approach and observed important advantages for therapeutic alliances, personalized treatment, and de-escalation strategies. Future studies will further conjoin clinical definitions of psychotic symptoms with brain structures and functions, and disentangle structural and functional deficit patterns within these systems to identify neurobiologically distinct subsyndromes. Neurobiologically homogeneous patient groups may provide new momentum for treatment research. Finally, lessons learned from schizophrenia research may contribute to developing a comprehensive perspective on human experience and behavior that integrates methodologically distinct, but internally consistent, insights from humanities and neuroscience.
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23
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Modinos G, Egerton A, McMullen K, McLaughlin A, Kumari V, Barker GJ, Williams SCR, Zelaya F. Increased resting perfusion of the hippocampus in high positive schizotypy: A pseudocontinuous arterial spin labeling study. Hum Brain Mapp 2018; 39:4055-4064. [PMID: 29885018 PMCID: PMC6174983 DOI: 10.1002/hbm.24231] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 05/08/2018] [Accepted: 05/15/2018] [Indexed: 12/16/2022] Open
Abstract
Arterial spin labeling (ASL) provides absolute quantification of resting tissue cerebral blood flow (CBF) as an entirely noninvasive approach with good reproducibility. As a result of neurovascular coupling, ASL provides a useful marker of resting neuronal activity. Recent ASL studies in individuals at clinical high risk of psychosis (CHR) have reported increased resting hippocampal perfusion compared with healthy controls. Schizotypy refers to the presence of subclinical psychotic-like experiences in healthy individuals and represents a robust framework to study neurobiological mechanisms involved in the extended psychosis phenotype while avoiding potentially confounding effects of antipsychotic medications or disease comorbidity. Here we applied pseudo-continuous ASL to examine differences in resting CBF in 21 subjects with high positive schizotypy (HS) relative to 22 subjects with low positive schizotypy (LS), as determined by the Oxford and Liverpool Inventory of Feelings and Experiences. Based on preclinical evidence that hippocampal hyperactivity leads to increased activity in mesostriatal dopamine projections, CBF in hippocampus, midbrain, and striatum was assessed. Participants with HS showed higher CBF of the right hippocampus compared to those with LS (p = .031, family-wise error corrected). No differences were detected in the striatum or midbrain. The association between increased hippocampal CBF and HS supports the notion that hippocampal hyperactivity might be a central characteristic of the extended psychosis phenotype, while hyperactivity in subcortical dopamine pathways may only emerge at a higher intensity of psychotic experiences.
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Affiliation(s)
- Gemma Modinos
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom.,Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Alice Egerton
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Katrina McMullen
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Anna McLaughlin
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Veena Kumari
- Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom.,Centre for Cognitive Neuroscience, College of Health and Life Sciences, Brunel University London, London, United Kingdom
| | - Gareth J Barker
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Steve C R Williams
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Fernando Zelaya
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
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24
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Scott D, Tamminga CA. Effects of genetic and environmental risk for schizophrenia on hippocampal activity and psychosis-like behavior in mice. Behav Brain Res 2018; 339:114-123. [PMID: 29155005 DOI: 10.1016/j.bbr.2017.10.039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 10/27/2017] [Accepted: 10/31/2017] [Indexed: 10/18/2022]
Abstract
Schizophrenia is a serious mental illness most notably characterized by psychotic symptoms. In humans, psychotic disorders are associated with specific hippocampal pathology. However, animal model systems for psychosis often lack this pathology, and have been weak in providing a representation of psychosis. We utilized a double-risk model system combining genetic risk with environmental stress. We hypothesized these factors will induce hippocampal subfield pathology consistent with human findings, as well as behavioral phenotypes relevant to psychosis. To address this, we exposed wild-type and transgenic Disc1 dominant negative (Disc1-deficient) mice to maternal deprivation. In adulthood, hippocampal subfields were examined for signs of cellular and behavioral pathology associated with psychosis. Mice exposed to maternal deprivation showed a decrease in dentate gyrus activity, and an increase in CA3/CA1 activity. Furthermore, results demonstrated a differential behavioral effect between maternal deprivation and Disc1 deficiency, with maternal deprivation associated with a hyperactive phenotype and impaired prepulse inhibition, and Disc1 deficiency causing an impairment in fear conditioning. These results suggest distinct consequences of environmental and genetic risk factors contributing to psychosis, with maternal deprivation inducing a state more wholly consistent with schizophrenia psychosis. Further research is needed to determine if this pathology is causally related to a specific behavioral phenotype. The development of a strong inference animal model system for psychosis would satisfy a high medical need in schizophrenia research.
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Affiliation(s)
- Daniel Scott
- Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas TX, 75390-9127, United States.
| | - Carol A Tamminga
- Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas TX, 75390-9127, United States
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25
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Drazanova E, Ruda-Kucerova J, Kratka L, Horska K, Demlova R, Starcuk Z, Kasparek T. Poly(I:C) model of schizophrenia in rats induces sex-dependent functional brain changes detected by MRI that are not reversed by aripiprazole treatment. Brain Res Bull 2017; 137:146-155. [PMID: 29155259 DOI: 10.1016/j.brainresbull.2017.11.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 11/06/2017] [Accepted: 11/08/2017] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND PURPOSE One of the hallmarks of schizophrenia is altered brain structure, potentially due to antipsychotic treatment, the disorder itself or both. It was proposed that functional changes may precede the structural ones. In order to understand and potentially prevent this unwanted process, brain function assessment should be validated as a diagnostic tool. METHODS We used Arterial Spin Labelling MRI technique for the evaluation of brain perfusion in several brain regions in a neurodevelopmental poly(I:C) model of schizophrenia (8mg/kg on a gestational day 15) in rats taking into account sex-dependent effects and chronic treatment with aripiprazole (30days), an atypical antipsychotic acting as a partial agonist on dopaminergic receptors. RESULTS We found the sex of the animal to have a highly significant effect in all regions of interest, with females showing lower blood perfusion than males. However, both males and females treated prenatally with poly(I:C) showed enlargement of the lateral ventricles. Furthermore, we detected increased perfusion in the circle of Willis, hippocampus, and sensorimotor cortex, which was not influenced by chronic atypical antipsychotic aripiprazole treatment in male poly(I:C) rats. CONCLUSION We hypothesize that perfusion alterations may be caused by the hyperdopaminergic activity in the poly(I:C) model, and the absence of aripiprazole effect on perfusion in brain regions related to schizophrenia may be due to its partial agonistic mechanism.
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Affiliation(s)
- Eva Drazanova
- Department of Pharmacology, Faculty of Medicine, Masaryk University, Brno, Czech Republic; Institute of Scientific Instruments, The Czech Academy of Sciences, Brno, Czech Republic
| | - Jana Ruda-Kucerova
- Department of Pharmacology, Faculty of Medicine, Masaryk University, Brno, Czech Republic.
| | - Lucie Kratka
- Institute of Scientific Instruments, The Czech Academy of Sciences, Brno, Czech Republic
| | - Katerina Horska
- Department of Human Pharmacology and Toxicology, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic
| | - Regina Demlova
- Department of Pharmacology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Zenon Starcuk
- Institute of Scientific Instruments, The Czech Academy of Sciences, Brno, Czech Republic
| | - Tomas Kasparek
- Department of Psychiatry, University Hospital and Masaryk University, Brno, Czech Republic
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26
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Stegmayer K, Stettler M, Strik W, Federspiel A, Wiest R, Bohlhalter S, Walther S. Resting state perfusion in the language network is linked to formal thought disorder and poor functional outcome in schizophrenia. Acta Psychiatr Scand 2017; 136:506-516. [PMID: 28865406 PMCID: PMC5656821 DOI: 10.1111/acps.12790] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/25/2017] [Indexed: 01/31/2023]
Abstract
OBJECTIVE Formal thought disorder (FTD) is a core symptom in schizophrenia. Here, we focus on resting state cerebral blood flow (rCBF) linked to dimensions of FTD. METHODS We included 47 schizophrenia spectrum patients and 30 age- and gender-matched healthy controls. We assessed FTD with the assessment of thought, language, and communication (TLC) and imaging on a 3T MRI scanner. Within patients, we tested the association of FTD dimensions and in a subgroup (n = 27) the association of functional outcome after 6 months with whole brain rCBF. RESULTS Negative FTD was most prominently associated with perfusion within the superior temporal gyrus, while positive FTD was associated with perfusion within the supplementary motor area, and inferior frontal gyrus. Perfusion within the left supramarginal gyrus was associated with social functioning after 6 months. CONCLUSIONS Distinguishable associations of rCBF with FTD dimensions point to distinct underlying pathophysiology. The location of aberrant perfusion patterns suggests that negative FTD might reflect defective access to semantic memory while positive FTD likely reflects defective suppression of irrelevant information during increased speech production. Finally, the neural correlates of thought block were also predictive of poor functional outcome. Thus, functional outcome and distinct FTD dimensions may share some pathophysiology.
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Affiliation(s)
- K. Stegmayer
- Translational Research CenterUniversity Hospital of PsychiatryUniversity of BernBernSwitzerland
| | - M. Stettler
- Translational Research CenterUniversity Hospital of PsychiatryUniversity of BernBernSwitzerland
| | - W. Strik
- Translational Research CenterUniversity Hospital of PsychiatryUniversity of BernBernSwitzerland
| | - A. Federspiel
- Translational Research CenterUniversity Hospital of PsychiatryUniversity of BernBernSwitzerland
| | - R. Wiest
- Support Center of Advanced Neuroimaging (SCAN)University Institute of Diagnostic and Interventional NeuroradiologyInselspitalBernSwitzerland
| | - S. Bohlhalter
- Neurology and Neurorehabilitation CenterKantonsspital LuzernLucerneSwitzerland
| | - S. Walther
- Translational Research CenterUniversity Hospital of PsychiatryUniversity of BernBernSwitzerland
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Ku HL, Wang JK, Lee HC, Lane TJ, Liu IC, Chen YC, Lee YT, Lin IC, Lin CP, Hu CJ, Chi NF. Cerebral blood flow autoregulation is impaired in schizophrenia: A pilot study. Schizophr Res 2017; 188:63-67. [PMID: 28108227 DOI: 10.1016/j.schres.2017.01.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 01/04/2017] [Accepted: 01/07/2017] [Indexed: 12/13/2022]
Abstract
Patients with schizophrenia have a higher risk of cardiovascular diseases and higher mortality from them than does the general population; however, the underlying mechanism remains unclear. Impaired cerebral autoregulation is associated with cerebrovascular diseases and their mortality. Increased or decreased cerebral blood flow in different brain regions has been reported in patients with schizophrenia, which implies impaired cerebral autoregulation. This study investigated the cerebral autoregulation in 21 patients with schizophrenia and 23 age- and sex-matched healthy controls. None of the participants had a history of cardiovascular diseases, hypertension, or diabetes. All participants underwent 10-min blood pressure and cerebral blood flow recording through finger plethysmography and Doppler ultrasonography, respectively. Cerebral autoregulation was assessed by analyzing two autoregulation indices: the mean blood pressure and cerebral blood flow correlation coefficient (Mx), and the phase shift between the waveforms of blood pressure and cerebral blood flow determined using transfer function analysis. Compared with the controls, the patients had a significantly higher Mx (0.257 vs. 0.399, p=0.036) and lower phase shift (44.3° vs. 38.7° in the 0.07-0.20Hz frequency band, p=0.019), which indicated impaired maintenance of constant cerebral blood flow and a delayed cerebrovascular autoregulatory response. Impaired cerebral autoregulation may be caused by schizophrenia and may not be an artifact of coexisting medical conditions. The mechanism underlying impaired cerebral autoregulation in schizophrenia and its probable role in the development of cerebrovascular diseases require further investigation.
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Affiliation(s)
- Hsiao-Lun Ku
- Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Brain and Consciousness Research Center, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan
| | - Jiunn-Kae Wang
- Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Brain and Consciousness Research Center, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan
| | - Hsin-Chien Lee
- Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Research Center of Sleep Medicine, College of Medicine, Taipei, Taiwan
| | - Timothy Joseph Lane
- Brain and Consciousness Research Center, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Graduate Institute of Humanities in Medicine, College of Humanities and Social Sciences, Taipei Medical University, Taipei, Taiwan; Institute of European and American Studies, Academia Sinica, Taipei, Taiwan; Research Center for Mind, Brain and Learning, National Chengchi University, Taipei, Taiwan
| | - I-Chao Liu
- Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Yung-Chan Chen
- Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan
| | - Yao-Tung Lee
- Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan
| | - I-Cheng Lin
- Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan
| | - Chia-Pei Lin
- Department of Psychiatry, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan
| | - Chaur-Jong Hu
- Department of Neurology, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Department of Neurology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Cerebrovascular Research Center, Taipei Medical University, Taipei, Taiwan
| | - Nai-Fang Chi
- Department of Neurology, Taipei Medical University Shuang Ho Hospital, New Taipei City, Taiwan; Department of Neurology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Cerebrovascular Research Center, Taipei Medical University, Taipei, Taiwan.
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28
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Roberts RC. Postmortem studies on mitochondria in schizophrenia. Schizophr Res 2017; 187:17-25. [PMID: 28189530 PMCID: PMC5550365 DOI: 10.1016/j.schres.2017.01.056] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 01/27/2017] [Accepted: 01/30/2017] [Indexed: 01/02/2023]
Abstract
The aim of this paper is to provide a brief review of mitochondrial structure as it relates to function and then present abnormalities in mitochondria in postmortem schizophrenia with a focus on ultrastructure. Function, morphology, fusion, fission, motility, ΔΨmem, ATP production, mitochondrial derived vesicles, and mitochondria-associated ER membranes will be briefly covered. Pathology in mitochondria has long been implicated in schizophrenia, as shown by genetic, proteomic, enzymatic and anatomical abnormalities. The cortex and basal ganglia will be reviewed. In the anterior cingulate cortex, the number of mitochondria per neuronal somata in layers 5/6 in schizophrenia is decreased by 43%. There are also fewer mitochondria in terminals forming axospinous synapses. In the caudate and putamen the number of mitochondria is abnormal in both glial cells and neurons in schizophrenia subjects, the extent of which depends on treatment, response and predominant lifetime symptoms. Treatment-responsive schizophrenia subjects had about a 40% decrease in the number of mitochondria per synapse in the caudate nucleus and putamen, while treatment resistant cases had normal values. A decrease in mitochondrial density in the neuropil distinguishes paranoid from undifferentiated schizophrenia. The appearance, size and density of mitochondria were normal in the nucleus accumbens. In the substantia nigra, COX subunits were affected in rostral regions. Mitochondrial hyperplasia occurs within axon terminals that synapse onto dopamine neurons, but mitochondria in dopamine neuronal somata are similar in size and number. In schizophrenia, mitochondria are differentially affected depending on the brain region, cell type, subcellular location, treatment status, treatment response and symptoms.
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Affiliation(s)
- Rosalinda C. Roberts
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama, Birmingham, AL 35294
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29
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Smucny J, Wylie KP, Kronberg E, Legget KT, Tregellas JR. Nicotinic modulation of salience network connectivity and centrality in schizophrenia. J Psychiatr Res 2017; 89:85-96. [PMID: 28193583 PMCID: PMC5373996 DOI: 10.1016/j.jpsychires.2017.01.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 01/09/2017] [Accepted: 01/12/2017] [Indexed: 12/27/2022]
Abstract
Although functional abnormalities of the salience network are associated with schizophrenia, the acute effects of nicotine on its function and network dynamics during the resting state in patients are poorly understood. In this study, the effects of a 7 mg nicotine patch (vs. placebo) on salience network connectivity were examined in 17 patients with schizophrenia and 19 healthy subjects. We hypothesized abnormal connectivity between the salience network and other major networks (e.g. executive network) in patients under placebo administration and amelioration of this difference after nicotine. We also examined effects of nicotine on betweenness centrality (a measure of the influence of a region on information transfer throughout the brain) and local efficiency (a measure of local information transfer) of the network. A hybrid independent component analysis (ICA)/seed-based connectivity approach was implemented in which the salience network was extracted by ICA and cortical network peaks (anterior cingulate cortex (ACC), left and right insula) were used as seeds for whole-brain seed-to-voxel connectivity analysis. Significant drug X diagnosis interactions were observed between the ACC seed and superior parietal lobule and ventrolateral prefrontal cortex. A significant interaction effect was also observed between the left insula seed and middle cingulate cortex. During placebo conditions, abnormal connectivity predicted negative symptom severity and lower global functioning in patients. A significant drug X diagnosis interaction was also observed for betweenness centrality of the ACC. These results suggest that nicotine may target abnormalities in functional connectivity between salience and executive network areas in schizophrenia as well as affect the ability of the salience network to act as an integrator of global signaling in the disorder.
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Affiliation(s)
- Jason Smucny
- Neuroscience Program, University of Colorado Anschutz Medical Campus, Aurora, CO, USA; Department of Psychiatry, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
| | - Korey P. Wylie
- Department of Psychiatry, University of Colorado Anschutz Medical Campus, Aurora CO USA
| | - Eugene Kronberg
- Department of Psychiatry, University of Colorado Anschutz Medical Campus, Aurora CO USA
| | - Kristina T. Legget
- Neuroscience Program, University of Colorado Anschutz Medical Campus, Aurora CO USA,Research Service, Denver VA Medical Center, Denver, CO USA,Department of Psychiatry, University of Colorado Anschutz Medical Campus, Aurora CO USA
| | - Jason R. Tregellas
- Neuroscience Program, University of Colorado Anschutz Medical Campus, Aurora CO USA,Research Service, Denver VA Medical Center, Denver, CO USA,Department of Psychiatry, University of Colorado Anschutz Medical Campus, Aurora CO USA
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30
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Ketamine modulates hippocampal neurochemistry and functional connectivity: a combined magnetic resonance spectroscopy and resting-state fMRI study in healthy volunteers. Mol Psychiatry 2017; 22:562-569. [PMID: 27480494 PMCID: PMC5562151 DOI: 10.1038/mp.2016.122] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 06/08/2016] [Accepted: 06/20/2016] [Indexed: 11/21/2022]
Abstract
A growing body of evidence suggests glutamate excess in schizophrenia and that N-methyl-d-aspartate receptor (NMDAR) hypofunction on γ-aminobutyric acid (GABA) interneurons disinhibiting pyramidal cells may be relevant to this hyperglutamatergic state. To better understand how NMDAR hypofunction affects the brain, we used magnetic resonance spectroscopy and resting-state functional magnetic resonance imaging (MRI) to study the effects of ketamine on hippocampal neurometabolite levels and functional connectivity in 15 healthy human subjects. We observed a ketamine-induced increase in hippocampal Glx (glutamate+glutamine; F=3.76; P=0.04), a decrease in fronto-temporal (t=4.92, PFDR<0.05, kE=2198, x=-30, y=52, z=14) and temporo-parietal functional connectivity (t=5.07, PFDR<0.05, kE=6094, x=-28, y=-36, z=-2), and a possible link between connectivity changes and elevated Glx. Our data empirically support that hippocampal glutamatergic elevation and resting-state network alterations may arise from NMDAR hypofunction and establish a proof of principle whereby experimental modelling of a disorder can help mechanistically integrate distinct neuroimaging abnormalities in schizophrenia.
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Talati P, Rane S, Donahue MJ, Heckers S. Hippocampal arterial cerebral blood volume in early psychosis. Psychiatry Res 2016; 256:21-25. [PMID: 27644028 PMCID: PMC5064837 DOI: 10.1016/j.pscychresns.2016.09.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Revised: 09/08/2016] [Accepted: 09/08/2016] [Indexed: 01/08/2023]
Abstract
Recent studies of patients in the early stage of psychosis have revealed increased cerebral blood volume (CBV) in specific subfields of the anterior hippocampus. These studies required injection of a contrast agent to measure steady state CBV. Here we used a novel, non-invasive method, inflow-based-vascular-space-occupancy with dynamic subtraction (iVASO-DS), to measure the arterial component of CBV (aCBV) in a single slice of the hippocampus. Based on evidence from contrast-enhanced CBV studies, we hypothesized increased aCBV in the anterior hippocampus in early psychosis. We used 3T MRI to generate iVASO-derived aCBV maps in 17 medicated patients (average duration of illness = 7.6 months) and 25 matched controls. We did not find hemispheric or regional group differences in hippocampal aCBV. The limited spatial resolution of the iVASO-DS method did not allow us to test for aCBV differences in specific subfields of the hippocampus. Future studies should investigate venous and arterial CBV changes in the hippocampus of early psychosis patients.
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Affiliation(s)
- Pratik Talati
- Vanderbilt Brain Institute, Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN 37212, USA.
| | - Swati Rane
- Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Radiology, University of Washington, Seattle, WA 98195, USA
| | - Manus J Donahue
- Vanderbilt Brain Institute, Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN 37212, USA; Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Stephan Heckers
- Vanderbilt Brain Institute, Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN 37212, USA
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Neural substrates underlying delusions in schizophrenia. Sci Rep 2016; 6:33857. [PMID: 27651212 PMCID: PMC5030611 DOI: 10.1038/srep33857] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 09/05/2016] [Indexed: 11/30/2022] Open
Abstract
Delusions are cardinal positive symptoms in schizophrenia; however, the neural substrates of delusions remain unknown. In the present study, we investigated the neural correlates of delusions in schizophrenia using multi-modal magnetic resonance imaging (MRI) techniques. Diffusion, structural and perfusion MRIs were performed in 19 schizophrenia patients with severe delusions, 30 patients without delusions and 30 healthy controls. Fractional anisotropy (FA), gray matter volume (GMV) and cerebral blood flow (CBF) were voxel-wisely compared among the three groups. Although patients without delusions exhibited decreased FA in white matter regions and decreased GMV in gray matter regions relative to controls, patients with severe delusions demonstrated comparable FA in all of these white matter regions and similar GMV in most of these gray matter regions. Both patient subgroups had less GMV in the amygdala and anterior cingulate cortex than controls. Although two patient subgroups showed consistent CBF changes relative to controls, only CBF in the anterior cingulate cortex was lower in patients with severe delusions than in patients without delusions. These findings suggest that schizophrenia patients with severe delusions have relatively normal structural integrity. Importantly, the excessively reduced perfusion in the anterior cingulate cortex may be associated with the development of delusions in schizophrenia.
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Hayashi-Takagi A. Synapse pathology and translational applications for schizophrenia. Neurosci Res 2016; 114:3-8. [PMID: 27633835 DOI: 10.1016/j.neures.2016.09.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 06/14/2016] [Accepted: 08/31/2016] [Indexed: 01/01/2023]
Abstract
Schizophrenia is a chronic, severe, and disabling brain disorder, with an estimated lifetime prevalence of 0.7%. Despite its relatively low prevalence, the onset of schizophrenia usually occurs early in life, resulting in a severe lifelong disability for patients and increasing the economic and care burden on their families. This makes schizophrenia one of the most catastrophic mental illnesses. Although the etiology of schizophrenia remains poorly understood, clinical, genetic, and pharmacological studies have indicated that its pathophysiology involves synaptic disturbances. Here, I review the evidence suggesting synaptic disturbance as the causal pathophysiology of schizophrenia and discuss the possible application of synaptic intervention as a novel therapeutic strategy for schizophrenia.
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Affiliation(s)
- Akiko Hayashi-Takagi
- Laboratory of Medical Neuroscience, Institute for Molecular and Cellular Regulation, Gunma University, Maebachi, Gunma 371-8512, Japan; PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
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De Rossi P, Chiapponi C, Spalletta G. Brain Functional Effects of Psychopharmacological Treatments in Schizophrenia: A Network-based Functional Perspective Beyond Neurotransmitter Systems. Curr Neuropharmacol 2016; 13:435-44. [PMID: 26412063 PMCID: PMC4790396 DOI: 10.2174/1570159x13666150507223542] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Psychopharmacological treatments for schizophrenia have always been a matter of debate and a very important issue in public health given the chronic, relapsing and disabling nature of the disorder. A thorough understanding of the pros and cons of currently available pharmacological treatments for schizophrenia is critical to better capture the features of treatment-refractory clinical pictures and plan the developing of new treatment strategies. This review focuses on brain functional changes induced by antipsychotic drugs as assessed by modern functional neuroimaging techniques (i.e. fMRI, PET, SPECT, MRI spectroscopy). The most important papers on this topic are reviewed in order to draw an ideal map of the main functional changes occurring in the brain during antipsychotic treatment. This supports the hypothesis that a network-based perspective and a functional connectivity approach are needed to fill the currently existing gap of knowledge in the field of psychotropic drugs and their mechanisms of action beyond neurotransmitter systems.
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Affiliation(s)
| | | | - Gianfranco Spalletta
- Neuropsychiatry Laboratory, Department of Clinical and Behavioural Neurology, IRCCS Santa Lucia Foundation, Via Ardeatina, 306, 00179 Rome, Italy.
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Kraguljac NV, White DM, Hadley N, Hadley JA, ver Hoef L, Davis E, Lahti AC. Aberrant Hippocampal Connectivity in Unmedicated Patients With Schizophrenia and Effects of Antipsychotic Medication: A Longitudinal Resting State Functional MRI Study. Schizophr Bull 2016; 42:1046-55. [PMID: 26873890 PMCID: PMC4903060 DOI: 10.1093/schbul/sbv228] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
To better characterize hippocampal pathophysiology in schizophrenia, we conducted a longitudinal study evaluating hippocampal functional connectivity during resting state, using seeds prescribed in its anterior and posterior regions. We enrolled 34 unmedicated patients with schizophrenia or schizoaffective disorder (SZ) and 34 matched healthy controls. SZ were scanned while off medication, then were treated with risperidone for 6 weeks and re-scanned (n = 22). Group differences in connectivity, as well as changes in connectivity over time, were assessed on the group's participant level functional connectivity maps. We found significant dysconnectivity with anterior and posterior hippocampal seeds in unmedicated SZ. Baseline connectivity between the hippocampus and anterior cingulate cortex, caudate nucleus, auditory cortex and calcarine sulcus in SZ predicted subsequent response to antipsychotic medications. These same regions demonstrated changes over the 6-week treatment trial that were correlated with symptomatic improvement. Our findings implicate several neural networks relevant to clinical improvement with antipsychotic medications.
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Affiliation(s)
- Nina Vanessa Kraguljac
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL
| | - David Matthew White
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL
| | - Nathan Hadley
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL
| | - Jennifer Ann Hadley
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL;,Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, AL
| | - Lawrence ver Hoef
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL
| | - Ebony Davis
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL
| | - Adrienne Carol Lahti
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL;
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36
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Park SC, Jang EY, Lee KU, Lee JG, Lee HY, Choi J. Psychometric Properties of the Korean Version of the Clinical Language Disorder Rating Scale (CLANG). CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE : THE OFFICIAL SCIENTIFIC JOURNAL OF THE KOREAN COLLEGE OF NEUROPSYCHOPHARMACOLOGY 2016; 14:49-56. [PMID: 26792040 PMCID: PMC4730933 DOI: 10.9758/cpn.2016.14.1.49] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 06/24/2015] [Accepted: 07/18/2015] [Indexed: 11/18/2022]
Abstract
OBJECTIVE Our study aimed to measure inter-rater and test-retest reliability, concurrent and convergent validity, and factor solutions of the Korean version of the Clinical Language Disorder Rating Scale (CLANG). METHODS The Korean version of the CLANG for assessing thought, language, and communication, the Brief Psychiatric Rating Scale, Young Mania Rating Scale, and Calgary Depression Scale for Schizophrenia were used to evaluate language disorder, formal thought disorder, positive and negative symptoms, manic symptoms, and depressive symptoms, respectively, in 167 hospitalized patients with schizophrenia. The factor solution was obtained by the direct oblimin method. A receiver operating characteristic curve was used to find the optimal cut-off score for discriminating schizophrenia patients with and without disorganized speech. RESULTS Inter-rater reliability was considered moderate (intraclass coefficient=0.67, F=3.30, p=0.04), and test-retest reliability was considered high (r=0.94, p<0.001). Five factors, namely, pragmatics, disclosure, production, prosody, and association, were identified. An optimal cut-off score of 7 points with 84.5% sensitivity and 81.7% specificity was proposed for distinguishing schizophrenia patients with and without disorganized speech. CONCLUSION Our findings suggest that the Korean version of the CLANG is a promising tool for evaluating language disorder in patients with schizophrenia.
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Affiliation(s)
- Seon-Cheol Park
- Department of Psychiatry, Yong-In Mental Hospital, Yongin, Cheonan,
Korea
- Institute of Mental Health, Hanyang University, Seoul, Cheonan,
Korea
| | - Eun Young Jang
- Department of Psychiatry, Hanyang University Guri Hospital, Guri, Cheonan,
Korea
| | - Kang Uk Lee
- Department of Psychiatry, Kangwon University School of Medicine, Chuncheon, Cheonan,
Korea
| | - Jung Goo Lee
- Department of Psychiatry, Inje University Haeundae Paik Hospital, Busan, Cheonan,
Korea
| | - Hwa-Young Lee
- Department of Psychiatry, Soonchunhyang University Cheonan Hospital, Cheonan,
Korea
| | - Joonho Choi
- Institute of Mental Health, Hanyang University, Seoul, Cheonan,
Korea
- Department of Psychiatry, Hanyang University Guri Hospital, Guri, Cheonan,
Korea
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37
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Reid MA, White DM, Kraguljac NV, Lahti AC. A combined diffusion tensor imaging and magnetic resonance spectroscopy study of patients with schizophrenia. Schizophr Res 2016; 170:341-50. [PMID: 26718333 PMCID: PMC5982513 DOI: 10.1016/j.schres.2015.12.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 12/03/2015] [Accepted: 12/07/2015] [Indexed: 12/31/2022]
Abstract
Diffusion tensor imaging (DTI) studies in schizophrenia consistently show global reductions in fractional anisotropy (FA), a putative marker of white matter integrity. The cingulum bundle, which facilitates communication between the anterior cingulate cortex (ACC) and hippocampus, is frequently implicated in schizophrenia. Magnetic resonance spectroscopy (MRS) studies report metabolic abnormalities in the ACC and hippocampus of patients. Combining DTI and MRS offers exploration of the relationship between cortical neuronal biochemistry and the integrity of white matter tracts connecting specific cortical regions; however, few studies have attempted this in schizophrenia. Twenty-nine schizophrenia patients and twenty controls participated in this 3 T imaging study in which we used DTI and tract-based spatial statistics (TBSS) to assess white matter integrity and MRS to quantify metabolites in the ACC and hippocampus. We found FA reductions with overlapping radial diffusivity (RD) elevations in patients in multiple tracts, suggesting white matter abnormalities in schizophrenia are driven by loss of myelin integrity. In controls, we found significant negative correlations between hippocampal N-acetylaspartate/creatine and RD and axial diffusivity (AD) as well as a significant negative correlation between FA and ACC glutamate+glutamine/creatine in the hippocampal part of the cingulum bundle. It is possible that the extent of myelin damage could have resulted in the absence of DTI-MRS correlations in our patient group. In conclusion, we demonstrate the potential utility of a multi-modal neuroimaging approach to help further our understanding of the relationship between white matter microstructure and neurochemistry in distinct cortical regions connected by white matter tracts.
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Affiliation(s)
- Meredith A. Reid
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA,Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, AL, USA
| | - David M. White
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Nina V. Kraguljac
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Adrienne C. Lahti
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA,To whom correspondence should be addressed: Adrienne C. Lahti, MD, Department of Psychiatry and Behavioral Neurobiology, The University of Alabama at Birmingham, SC 501, 1720 2 Ave S, Birmingham, AL 35294-0017, USA, +1 205-996-6776, Fax: +1 205-975-4879,
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38
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Perez SM, Aguilar DD, Neary JL, Carless MA, Giuffrida A, Lodge DJ. Schizophrenia-Like Phenotype Inherited by the F2 Generation of a Gestational Disruption Model of Schizophrenia. Neuropsychopharmacology 2016; 41:477-86. [PMID: 26068729 PMCID: PMC5130123 DOI: 10.1038/npp.2015.169] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 06/08/2015] [Accepted: 06/09/2015] [Indexed: 01/13/2023]
Abstract
Both environmental and genetic factors contribute to schizophrenia; however, the exact etiology of this disorder is not known. Animal models are utilized to better understand the mechanisms associated with neuropsychiatric diseases, including schizophrenia. One of these involves gestational administration of methylazoxymethanol acetate (MAM) to induce a developmental disruption, which in turn produces a schizophrenia-like phenotype in post-pubertal rats. The mechanisms by which MAM produces this phenotype are not clear; however, we now demonstrate that MAM induces differential DNA methylation, which may be heritable. Here we demonstrate that a subset of both second (F2) and third (F3) filial generations of MAM-treated rats displays a schizophrenia-like phenotype and hypermethylation of the transcription factor, Sp5. Specifically, ventral tegmental area of dopamine neuron activity was examined using electrophysiology as a correlate for the dopamine hyperfunction thought to underlie psychosis in patients. Interestingly, only a subset of F2 and F3 MAM rats exhibited increases in dopamine neuron population activity, indicating that this may be a unique model with a susceptibility to develop a schizophrenia-like phenotype. An increase in dopamine system function in rodent models has been previously associated with decreases in hippocampal GABAergic transmission. In line with these observations, we found a significant correlation between hippocampal parvalbumin expression and dopamine neuron activity in F2 rats. These data therefore provide evidence that offspring born from MAM-treated rats possess a susceptibility to develop aspects of a schizophrenia-like phenotype and may provide a useful tool to investigate gene-environment interactions.
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Affiliation(s)
- Stephanie M Perez
- Department of Pharmacology, Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - David D Aguilar
- Department of Pharmacology, Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Jennifer L Neary
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Melanie A Carless
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Andrea Giuffrida
- Department of Pharmacology, Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Daniel J Lodge
- Department of Pharmacology, Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
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Rivolta D, Heidegger T, Scheller B, Sauer A, Schaum M, Birkner K, Singer W, Wibral M, Uhlhaas PJ. Ketamine Dysregulates the Amplitude and Connectivity of High-Frequency Oscillations in Cortical-Subcortical Networks in Humans: Evidence From Resting-State Magnetoencephalography-Recordings. Schizophr Bull 2015; 41:1105-14. [PMID: 25987642 PMCID: PMC4535642 DOI: 10.1093/schbul/sbv051] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Hypofunctioning of the N-methyl-D-aspartate receptor (NMDA-R) has been prominently implicated in the pathophysiology of schizophrenia (ScZ). The current study tested the effects of ketamine, a dissociative anesthetic and NMDA-R antagonist, on resting-state activity recorded with magnetoencephalography (MEG) in healthy volunteers. In a single-blind cross-over design, each participant (n = 12) received, on 2 different sessions, a subanesthetic dose of S-ketamine (0.006 mg/Kg) and saline injection. MEG-data were analyzed at sensor- and source-level in the beta (13-30 Hz) and gamma (30-90 Hz) frequency ranges. In addition, connectivity analysis at source-level was performed using transfer entropy (TE). Ketamine increased gamma-power while beta-band activity was decreased. Specifically, elevated 30-90 Hz activity was pronounced in subcortical (thalamus and hippocampus) and cortical (frontal and temporal cortex) regions, whilst reductions in beta-band power were localized to the precuneus, cerebellum, anterior cingulate, temporal and visual cortex. TE analysis demonstrated increased information transfer in a thalamo-cortical network after ketamine administration. The findings are consistent with the pronounced dysregulation of high-frequency oscillations following the inhibition of NMDA-R in animal models of ScZ as well as with evidence from electroencephalogram-data in ScZ-patients and increased functional connectivity during early illness stages. Moreover, our data highlight the potential contribution of thalamo-cortical connectivity patterns towards ketamine-induced neuronal dysregulation, which may be relevant for the understanding of ScZ as a disorder of disinhibition of neural circuits.
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Affiliation(s)
- Davide Rivolta
- Department of Neurophysiology, Max Planck Institute for Brain Research, Frankfurt am Main, Germany;,Ernst Strüngmann Institute for Neuroscience (ESI) in cooperation with Max Planck Society (ESI), Frankfurt am Main, Germany;,School of Psychology, University of East London (UEL), London, UK
| | - Tonio Heidegger
- Department of Neurology, Goethe University, Frankfurt am Main, Germany
| | - Bertram Scheller
- Clinic for Anesthesia, Intensive Care Medicine and Pain Therapy, Johann Wolfgang Goethe UniversityFrankfurt am Main, Germany
| | - Andreas Sauer
- Department of Neurophysiology, Max Planck Institute for Brain Research, Frankfurt am Main, Germany;,Ernst Strüngmann Institute for Neuroscience (ESI) in cooperation with Max Planck Society (ESI), Frankfurt am Main, Germany
| | | | - Katharina Birkner
- Department of Neurophysiology, Max Planck Institute for Brain Research, Frankfurt am Main, Germany;,Ernst Strüngmann Institute for Neuroscience (ESI) in cooperation with Max Planck Society (ESI), Frankfurt am Main, Germany
| | - Wolf Singer
- Department of Neurophysiology, Max Planck Institute for Brain Research, Frankfurt am Main, Germany;,Ernst Strüngmann Institute for Neuroscience (ESI) in cooperation with Max Planck Society (ESI), Frankfurt am Main, Germany;,Frankfurt Institute for Advanced Studies (FIAS), Frankfurt am Main, Germany
| | | | - Peter J. Uhlhaas
- Department of Neurophysiology, Max Planck Institute for Brain Research, Frankfurt am Main, Germany;,Ernst Strüngmann Institute for Neuroscience (ESI) in cooperation with Max Planck Society (ESI), Frankfurt am Main, Germany;,Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, UK,*To whom correspondence should be addressed; Institute of Neuroscience and Psychology, University of Glasgow, Hillead Street 58, Glasgow, G12 8QB, UK; tel: 44-141-330-8730, fax: 44-141-330-8730, e-mail:
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40
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Gao B, Wang Y, Liu W, Chen Z, Zhou H, Yang J, Cohen Z, Zhu Y, Zang Y. Spontaneous Activity Associated with Delusions of Schizophrenia in the Left Medial Superior Frontal Gyrus: A Resting-State fMRI Study. PLoS One 2015. [PMID: 26204264 PMCID: PMC4512714 DOI: 10.1371/journal.pone.0133766] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Delusions of schizophrenia have been found to be associated with alterations of some brain regions in structure and task-induced activation. However, the relationship between spontaneously occurring symptoms and spontaneous brain activity remains unclear. In the current study, 14 schizophrenic patients with delusions and 14 healthy controls underwent a resting-state functional magnetic resonance imaging (RS-fMRI) scan. Patients with delusions of schizophrenia patients were rated with Positive and Negative Syndrome Scale (PANSS) and Characteristics of Delusional Rating Scale (CDRS). Regional homogeneity (ReHo) was calculated to measure the local synchronization of the spontaneous activity in a voxel-wise way. A two-sample t-test showed that ReHo of the right anterior cingulate gyrus and left medial superior frontal gyrus were higher in patients, and ReHo of the left superior occipital gyrus was lower, compared to healthy controls. Further, among patients, correlation analysis showed a significant difference between delusion scores of CRDS and ReHo of brain regions. ReHo of the left medial superior frontal gyrus was negatively correlated with patients’ CDRS scores but not with delusional PANSS scores. These results suggested that altered local synchronization of spontaneous brain activity may be related to the pathophysiology of delusion in schizophrenia.
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Affiliation(s)
- Bin Gao
- Department of Psychiatry, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, PR China
| | - Yiquan Wang
- Hangzhou Seventh People's Hospital, Hangzhou, Zhejiang, PR China; Mental Health Center, School of Medicine, Zhe Jiang University, Hangzhou, Zhejiang, PR China
| | - Weibo Liu
- Department of Psychiatry, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, PR China
| | - Zhiyu Chen
- Hangzhou Seventh People's Hospital, Hangzhou, Zhejiang, PR China
| | - Heshan Zhou
- Hangzhou First People's Hospital, Hangzhou, Zhejiang, PR China
| | - Jinyu Yang
- Department of Public Health, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, PR China
| | - Zachary Cohen
- Alpert Medical School of Brown University, Richmond St., Providence, RI, United States of America
| | - Yihong Zhu
- Department of Public Health, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, PR China; Mental Health Education and Counseling Center, Zhejiang University, Hangzhou, Zhejiang, PR China
| | - Yufeng Zang
- Center for Cognition and Brain Disorders, Hangzhou Normal University, Hangzhou, Zhejiang, PR China; Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments, Hangzhou, Zhejiang, PR China
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41
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Tamminga CA, Zukin RS. Schizophrenia: Evidence implicating hippocampal GluN2B protein and REST epigenetics in psychosis pathophysiology. Neuroscience 2015. [PMID: 26211447 DOI: 10.1016/j.neuroscience.2015.07.038] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The hippocampus is strongly implicated in the psychotic symptoms of schizophrenia. Functionally, basal hippocampal activity (perfusion) is elevated in schizophrenic psychosis, as measured with positron emission tomography (PET) and with magnetic resonance (MR) perfusion techniques, while hippocampal activation to memory tasks is reduced. Subfield-specific hippocampal molecular pathology exists in human psychosis tissue which could underlie this neuronal hyperactivity, including increased GluN2B-containing NMDA receptors in hippocampal CA3, along with increased postsynaptic density protein-95 (PSD-95) along with augmented dendritic spines on the pyramidal neuron apical dendrites. We interpret these observations to implicate a reduction in the influence of a ubiquitous gene repressor, repressor element-1 silencing transcription factor (REST) in psychosis; REST is involved in the age-related maturation of the NMDA receptor from GluN2B- to GluN2A-containing NMDA receptors through epigenetic remodeling. These CA3 changes in psychosis leave the hippocampus liable to pathological increases in neuronal activity, feedforward excitation and false memory formation, sometimes with psychotic content.
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Affiliation(s)
- C A Tamminga
- UT Southwestern Medical School, Dallas, TX, United States.
| | - R S Zukin
- Albert Einstein School of Medicine, New York, NY, United States
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Talati P, Rane S, Skinner J, Gore J, Heckers S. Increased hippocampal blood volume and normal blood flow in schizophrenia. Psychiatry Res 2015; 232:219-25. [PMID: 25896442 PMCID: PMC4439302 DOI: 10.1016/j.pscychresns.2015.03.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Revised: 03/07/2015] [Accepted: 03/27/2015] [Indexed: 11/27/2022]
Abstract
Neuroimaging studies have provided compelling evidence for abnormal hippocampal activity in schizophrenia. Most studies made inferences about baseline hippocampal activity using a single hemodynamic parameter (e.g., blood volume or blood flow). Here we studied several hemodynamic measures in the same cohort to test the hypothesis of increased hippocampal activity in schizophrenia. We used dynamic susceptibility contrast- (DSC-) magnetic resonance imaging (MRI) to assess blood volume, blood flow, and mean transit time in the hippocampus of 15 patients with chronic schizophrenia and 15 healthy controls. Left and right hippocampal measurements were combined for absolute measures of cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT). We found significantly increased hippocampal CBV, but normal CBF and MTT, in schizophrenia. The uncoupling of CBV and CBF could be due to several factors, including antipsychotic medication, loss of cerebral perfusion pressure, or angiogenesis. Further studies need to incorporate several complementary imaging modalities to better characterize hippocampal dysfunction in schizophrenia.
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Affiliation(s)
- Pratik Talati
- Vanderbilt Brain Institute, Department of Psychiatry, Vanderbilt University, Nashville, TN 37212 USA.
| | - Swati Rane
- Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN 37232 USA.
| | - Jack Skinner
- Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, 37232 USA
| | - John Gore
- Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, 37232 USA
| | - Stephan Heckers
- Vanderbilt Brain Institute, Department of Psychiatry, Vanderbilt University, Nashville, TN, 37212 USA
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Ohtani T, Bouix S, Lyall AE, Hosokawa T, Saito Y, Melonakos E, Westin CF, Seidman LJ, Goldstein J, Mesholam-Gately R, Petryshen T, Wojcik J, Kubicki M. Abnormal white matter connections between medial frontal regions predict symptoms in patients with first episode schizophrenia. Cortex 2015; 71:264-76. [PMID: 26277547 DOI: 10.1016/j.cortex.2015.05.028] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Revised: 04/17/2015] [Accepted: 05/26/2015] [Indexed: 12/11/2022]
Abstract
INTRODUCTION The medial orbitofrontal cortex (mOFC) and rostral part of anterior cingulate cortex (rACC) have been suggested to be involved in the neural network of salience and emotional processing, and associated with specific clinical symptoms in schizophrenia. Considering the schizophrenia dysconnectivity hypothesis, the connectivity abnormalities between mOFC and rACC might be associated with clinical characteristics in first episode schizophrenia patients (FESZ). METHODS After parcellating mOFC into the anterior and posterior part, diffusion properties of the mOFC-rACC white matter connections for 21 patients with FESZ and 21 healthy controls (HCs) were examined using stochastic tractography, one of the most effective Diffusion Tensor Imaging (DTI) methods for examining tracts between adjacent gray matter (GM) regions. RESULTS Fractional anisotropy (FA) reductions were observed in bilateral posterior, but not anterior mOFC-rACC connections (left: p < .0001; right: p < .0001) in FESZ compared to HCs. In addition, reduced FA in the left posterior mOFC-rACC connection was associated with more severe anhedonia-asociality (rho = -.633, p = .006) and total score (rho = -.520, p = .032) in the Scale for the Assessment of Negative Symptoms (SANS); reduced FA in the right posterior mOFC-rACC connection was associated with more severe affective flattening (rho = -.644, p = .005), total score (rho = -.535, p = .027) in SANS, hallucinations (rho = -.551, p = .018), delusions (rho = -.632, p = .005) and total score (rho = -.721, p = .001) in the Scale for the Assessment of Positive Symptoms (SAPS) in FESZ. CONCLUSIONS The observed white matter abnormalities within the connections between mOFC and rACC might be associated with the psychopathology of the early stage of schizophrenia.
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Affiliation(s)
- Toshiyuki Ohtani
- Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; VA Boston Healthcare System, Boston, MA, USA; Safety and Health Organization, Chiba University, Chiba City, Chiba, Japan
| | - Sylvain Bouix
- Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Amanda E Lyall
- Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Taiga Hosokawa
- Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; VA Boston Healthcare System, Boston, MA, USA; Tsuchida Hospital, Tokyo, Japan
| | - Yukiko Saito
- Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Department of Neuropsychiatry, Kansai Medical University, Moriguchi City, Osaka, Japan
| | - Eric Melonakos
- Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Carl-Fredrik Westin
- Surgical Planning Laboratory, MRI Division, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Larry J Seidman
- Massachusetts Mental Health Center Public Psychiatry Division, Beth Israel Deaconess Medical Center, Department of Psychiatry, Harvard Medical School, Boston, MA, USA; Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Jill Goldstein
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Raquelle Mesholam-Gately
- Massachusetts Mental Health Center Public Psychiatry Division, Beth Israel Deaconess Medical Center, Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Tracey Petryshen
- Stanley Center of Psychiatry Research, Broad Institute of MIT and Harvard, Boston, MA, USA; Psychiatry and Neurodevelopmental Genetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA, USA
| | - Joanne Wojcik
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Marek Kubicki
- Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; VA Boston Healthcare System, Boston, MA, USA.
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Li W, Ghose S, Gleason K, Begovic’ A, Perez J, Bartko J, Russo S, Wagner AD, Selemon L, Tamminga CA. Synaptic proteins in the hippocampus indicative of increased neuronal activity in CA3 in schizophrenia. Am J Psychiatry 2015; 172:373-82. [PMID: 25585032 PMCID: PMC4457341 DOI: 10.1176/appi.ajp.2014.14010123] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
OBJECTIVE In schizophrenia, hippocampal perfusion is increased and declarative memory function is degraded. Based on an a priori model of hippocampal dysfunction in schizophrenic psychosis, the authors postulated molecular and cellular changes in CA3 consistent with increased NMDA receptor signaling. METHOD Postmortem hippocampal subfield tissue (CA3, CA1) from subjects with schizophrenia and nonpsychiatric comparison subjects was analyzed using Western blotting and Golgi histochemistry to examine the hypothesized outcomes. RESULTS The GluN2B-containing NMDA receptors (GluN2B/GluN1) and their associated postsynaptic membrane protein PSD95 were both increased in schizophrenia in CA3 tissue, but not in CA1 tissue. Quantitative analyses of Golgi-stained hippocampal neurons showed an increase in spine density on CA3 pyramidal cell apical dendrites (stratum radiatum) and an increase in the number of thorny excrescences. CONCLUSIONS The hippocampal data are consistent with increased excitatory signaling in CA3 and/or with an elevation in silent synapses in CA3, a state that may contribute to an increase in long-term potentiation in CA3 with subsequent stimulation and "unsilencing." These changes are plausibly associated with increased associational activity in CA3, with degraded declarative memory function, and with formation of false memories with psychotic content. The influence of these hyperactive hippocampal projections on targets in the limbic neocortex could contribute to components of schizophrenia manifestations in other cerebral regions.
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Affiliation(s)
- Wei Li
- Division of Translational Neuroscience in Schizophrenia, Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Subroto Ghose
- Division of Translational Neuroscience in Schizophrenia, Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Kelly Gleason
- Division of Translational Neuroscience in Schizophrenia, Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Anita Begovic’
- Department of Neurobiology, Yale University School of Medicine, New Haven, CT 06510
| | - Jessica Perez
- Division of Translational Neuroscience in Schizophrenia, Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - John Bartko
- Division of Translational Neuroscience in Schizophrenia, Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Scott Russo
- Neuroscience Department, Mount Sinai Medical School, NY NY 10029
| | - Anthony D. Wagner
- Department of Psychology and Neuroscience Program, Stanford University, Palo Alto, CA 94305
| | - Lynn Selemon
- Department of Neurobiology, Yale University School of Medicine, New Haven, CT 06510
| | - Carol A. Tamminga
- Division of Translational Neuroscience in Schizophrenia, Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390
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Zhu J, Zhuo C, Qin W, Xu Y, Xu L, Liu X, Yu C. Altered resting-state cerebral blood flow and its connectivity in schizophrenia. J Psychiatr Res 2015; 63:28-35. [PMID: 25812945 DOI: 10.1016/j.jpsychires.2015.03.002] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 02/28/2015] [Accepted: 03/05/2015] [Indexed: 10/23/2022]
Abstract
Small sample sizes and large inter-subject variations result in inconsistent findings in resting-state cerebral blood flow (CBF) in schizophrenia. The CBF connectivity alterations in schizophrenia remain unclear. Recently, three-dimensional pseudo-continuous arterial spin labeling (pcASL) imaging was performed to measure the resting-state CBF in 100 schizophrenia patients and 94 healthy comparison subjects. The normalized CBF was used to reduce the inter-subject variations. Both group comparisons in the CBF and correlations between the CBF alterations and clinical parameters were assessed. The CBF connectivity of the brain regions with regional CBF differences was also compared between the groups. Compared with the healthy controls, the schizophrenia patients exhibited increased CBF in the bilateral inferior temporal gyri, thalami and putamen and decreased CBF in the left insula and middle frontal gyrus and the bilateral anterior cingulate cortices and middle occipital gyri. In the schizophrenia patients, significant correlations were identified between the CBF and clinical parameters. Importantly, the schizophrenia patients exhibited CBF disconnections between the left thalamus and right medial superior frontal gyrus and between the left insula and left postcentral gyrus. Our results suggest that schizophrenia patients may exhibit both regional CBF abnormalities and deficits in CBF connectivity, which may underlie the clinical symptoms of schizophrenia.
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Affiliation(s)
- Jiajia Zhu
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China
| | - Chuanjun Zhuo
- Tianjin Anning Hospital, Tianjin 300300, China; Department of Psychiatry Functional Neuroimaging Laboratory, Tianjin Mental Health Center, Tianjin Anding Hospital, Tianjin 300070, China
| | - Wen Qin
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China
| | - Yongjie Xu
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China
| | - Lixue Xu
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China
| | - Xingyun Liu
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China
| | - Chunshui Yu
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China.
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Padmanabhan JL, Tandon N, Haller CS, Mathew IT, Eack SM, Clementz BA, Pearlson GD, Sweeney JA, Tamminga CA, Keshavan MS. Correlations between brain structure and symptom dimensions of psychosis in schizophrenia, schizoaffective, and psychotic bipolar I disorders. Schizophr Bull 2015; 41:154-62. [PMID: 24907239 PMCID: PMC4266291 DOI: 10.1093/schbul/sbu075] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Structural alterations may correlate with symptom severity in psychotic disorders, but the existing literature on this issue is heterogeneous. In addition, it is not known how cortical thickness and cortical surface area correlate with symptom dimensions of psychosis. METHODS Subjects included 455 individuals with schizophrenia, schizoaffective, or bipolar I disorders. Data were obtained as part of the Bipolar Schizophrenia Network for Intermediate Phenotypes study. Diagnosis was made through the Structured Clinical Interview for DSM-IV. Positive and negative symptom subscales were assessed using the Positive and Negative Syndrome Scale. Structural brain measurements were extracted from T1-weight structural MRIs using FreeSurfer v5.1 and were correlated with symptom subscales using partial correlations. Exploratory factor analysis was also used to identify factors among those regions correlating with symptom subscales. RESULTS The positive symptom subscale correlated inversely with gray matter volume (GMV) and cortical thickness in frontal and temporal regions, whereas the negative symptom subscale correlated inversely with right frontal cortical surface area. Among regions correlating with the positive subscale, factor analysis identified four factors, including a temporal cortical thickness factor and frontal GMV factor. Among regions correlating with the negative subscale, factor analysis identified a frontal GMV-cortical surface area factor. There was no significant diagnosis by structure interactions with symptom severity. CONCLUSIONS Structural measures correlate with positive and negative symptom severity in psychotic disorders. Cortical thickness demonstrated more associations with psychopathology than cortical surface area.
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Affiliation(s)
- Jaya L. Padmanabhan
- Department of Psychiatry, Beth Israel Deaconess Medical Center, Boston, MA;,Division of Public Psychiatry, Massachusetts Mental Health Center, Boston, MA
| | - Neeraj Tandon
- Department of Psychiatry, Beth Israel Deaconess Medical Center, Boston, MA;,Division of Public Psychiatry, Massachusetts Mental Health Center, Boston, MA
| | | | - Ian T. Mathew
- Department of Psychiatry, Beth Israel Deaconess Medical Center, Boston, MA;,Division of Public Psychiatry, Massachusetts Mental Health Center, Boston, MA
| | - Shaun M. Eack
- School of Social Work, Psychiatry, and Clinical and Translational Sciences Institute, University of Pittsburgh, Pittsburgh, PA;,Western Psychiatric Institute and Clinic, Pittsburgh, PA
| | - Brett A. Clementz
- Departments of Psychiatry and Neuroscience, Bio-Imaging Research Center, University of Georgia, Athens, GA
| | - Godfrey D. Pearlson
- Departments of Psychiatry and Neurobiology, Yale University, New Haven, CT;,Olin Neuropsychiatry Research Center, Hartford Hospital/Institute of Living, Hartford, CT
| | - John A. Sweeney
- Department of Psychiatry, University of Illinois at Chicago, Chicago, IL;,Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX
| | - Carol A. Tamminga
- Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX
| | - Matcheri S. Keshavan
- Department of Psychiatry, Beth Israel Deaconess Medical Center, Boston, MA;,Division of Public Psychiatry, Massachusetts Mental Health Center, Boston, MA;,Department of Psychiatry, Harvard Medical School, Boston, MA;,*To whom correspondence should be addressed; Division of Public Psychiatry, Massachusetts Mental Health Center, 75 Fenwood Road, Boston, MA 02115, US; tel: 617-754-1256, fax: 617-754-1250, e-mail:
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Hutcheson NL, Sreenivasan KR, Deshpande G, Reid MA, Hadley J, White DM, Ver Hoef L, Lahti AC. Effective connectivity during episodic memory retrieval in schizophrenia participants before and after antipsychotic medication. Hum Brain Mapp 2014; 36:1442-57. [PMID: 25504918 DOI: 10.1002/hbm.22714] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 11/07/2014] [Accepted: 12/01/2014] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Impairment in episodic memory is one of the most robust findings in schizophrenia. Disruptions of fronto-temporal functional connectivity that could explain some aspects of these deficits have been reported. Recent work has identified abnormal hippocampal function in unmedicated patients with schizophrenia (SZ), such as increased metabolism and glutamate content that are not always seen in medicated SZ. For these reasons, we hypothesized that altered fronto-temporal connectivity might originate from the hippocampus and might be partially restored by antipsychotic medication. METHODS Granger causality methods were used to evaluate the effective connectivity between frontal and temporal regions in 21 unmedicated SZ and 20 matched healthy controls (HC) during performance of an episodic memory retrieval task. In 16 SZ, effective connectivity between these regions was evaluated before and after 1-week of antipsychotic treatment. RESULTS In HC, significant effective connectivity originating from the right hippocampus to frontal regions was identified. Compared to HC, unmedicated SZ showed significant altered fronto-temporal effective connectivity, including reduced right hippocampal to right medial frontal connectivity. After 1-week of antipsychotic treatment, connectivity more closely resembled the patterns observed in HC, including increased effective connectivity from the right hippocampus to frontal regions. CONCLUSIONS These results support the notion that memory disruption in schizophrenia might originate from hippocampal dysfunction and that medication restores some aspects of fronto-temporal dysconnectivity. Patterns of fronto-temporal connectivity could provide valuable biomarkers to identify new treatments for the symptoms of schizophrenia, including memory deficits.
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Affiliation(s)
- Nathan L Hutcheson
- Department of Psychiatry and Behavioral Neurobiology, The University of Alabama at Birmingham, Birmingham, Alabama
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Altered coupling of regional cerebral blood flow and brain temperature in schizophrenia compared with bipolar disorder and healthy subjects. J Cereb Blood Flow Metab 2014; 34:1868-72. [PMID: 25182665 PMCID: PMC4269739 DOI: 10.1038/jcbfm.2014.151] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 06/19/2014] [Accepted: 07/29/2014] [Indexed: 12/30/2022]
Abstract
Previous studies have suggested that schizophrenia patients have dysfunctional thermoregulation. The aim of this study was to examine whether brain temperature (BT) in schizophrenia patients differs from that in patients with bipolar disorder and healthy subjects by using magnetic resonance imaging. We also evaluated the possible relationship between BT and cerebral blood flow (CBF). We analyzed the temperature of lateral ventricles as the mean BT using diffusion-weighted imaging (DWI) thermometry, and evaluated the relationships between the BT and the CBF using pseudo-continuous arterial spin labeling (pCASL) among 3 diagnostic groups, 22 male patients with schizophrenia, 19 male patients with bipolar disorder, and 23 healthy male subjects. There were significant positive correlations between BT in the lateral ventricles and CBF in both the patients with bipolar disorder and healthy subjects. By contrast, there were significant negative correlations in patients with schizophrenia. We could not detect the significant difference in the surrogates of BT among three diagnostic groups. We showed that patients with schizophrenia, but not those with bipolar disorder, have dysfunctional thermoregulation in the brain. Brain temperature is highly dependent on cerebral metabolism and CBF, and thus uncoupling of cerebral metabolism and CBF may occur in schizophrenics.
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Thoresen C, Endestad T, Sigvartsen NPB, Server A, Bolstad I, Johansson M, Andreassen OA, Jensen J. Frontotemporal hypoactivity during a reality monitoring paradigm is associated with delusions in patients with schizophrenia spectrum disorders. Cogn Neuropsychiatry 2014; 19:97-115. [PMID: 23756081 DOI: 10.1080/13546805.2013.776495] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
INTRODUCTION Impaired monitoring of internally generated information has been proposed to be one component in the development and maintenance of delusions. The present study investigated the neural correlates underlying the monitoring processes and whether they were associated with delusions. METHODS Twenty healthy controls and 19 patients with schizophrenia spectrum disorders were administrated a reality monitoring paradigm during functional magnetic resonance imaging. During encoding participants were instructed to associate a statement with either a presented (viewed condition) or an imagined picture (imagined condition). During the monitoring session in the scanner, participants were presented with old and new statements and their task was to identify whether a given statement was associated with the viewed condition, imagined condition, or if it was new. RESULTS Patients showed significantly reduced accuracy in the imagined condition with performance negatively associated with degree of delusions. This was accompanied with reduced activity in the left dorsolateral prefrontal cortex and left hippocampus in the patient group. The severity of delusions was negatively correlated with the blood-oxygenation-level dependent response in the left hippocampus. CONCLUSIONS The results suggest that weakened monitoring is associated with delusions in patients with schizophrenia spectrum disorder, and that this may be mediated by a frontotemporal dysfunction.
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Affiliation(s)
- Christian Thoresen
- a Division of Mental Health and Addiction , Oslo University Hospital , Oslo , Norway
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Synaptic proteins in the postmortem anterior cingulate cortex in schizophrenia: relationship to treatment and treatment response. Neuropsychopharmacology 2014; 39:2095-103. [PMID: 24603856 PMCID: PMC4104326 DOI: 10.1038/npp.2014.57] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 02/14/2014] [Accepted: 03/04/2014] [Indexed: 12/27/2022]
Abstract
The anterior cingulate cortex (ACC) is one of several brain regions that are abnormal in schizophrenia (SZ). Here we compared markers of synapse and mitochondrial function using western blots of postmortem ACC in: 1) normal controls (NCs, n=13) vs subjects with SZ (n=25); NC, treatment-resistant SZ, and treatment-responsive SZ; and 3) NC and SZ treated with typical or atypical antipsychotic drugs (APDs). Protein levels of synaptophysin, mitofusin-2, vGLUT1, and calcineurin did not differ between the NC and SZ group as a whole, or the NCs vs the SZ group divided by treatment response or type of APDs. In several cases, the levels of vGLUT1 were minuscule or absent. The proportion of NCs lacking vGLUT1 was significantly less than that of the SZ groups. There were several positive correlations across all subjects between: 1) synaptophysin and vGLUT1; 2) synaptophysin and calcineurin; 3) synaptophysin and mitofusin; and 4) calcineurin and mitofusin. Synaptophysin and calcineurin were positively correlated in responders, and this correlation was significantly stronger than that in treatment-resistant SZ subjects or in NCs. Synaptophysin and calcineurin were positively correlated in SZ patients on atypical APDs; this correlation was significantly stronger than that in SZ patients on typical APDs or in NCs. Mitofusin-2 and calcineurin were positively correlated in SZ patients on atypical APDs and in NCs; this correlation was stronger in SZ patients on atypical rather than typical APDs or in NCs. The correlation between these proteins, which have roles in synaptic vesicle cycling, glutamate transmission, mitochondrial fusion, and calcium buffering, is complex and was differentially regulated among the groups.
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