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Boroń A, Śmiarowska M, Grzywacz A, Chmielowiec K, Chmielowiec J, Masiak J, Pawłowski T, Larysz D, Ciechanowicz A. Association of Polymorphism within the Putative miRNA Target Site in the 3'UTR Region of the DRD2 Gene with Neuroticism in Patients with Substance Use Disorder. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:9955. [PMID: 36011589 PMCID: PMC9408599 DOI: 10.3390/ijerph19169955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 08/08/2022] [Accepted: 08/10/2022] [Indexed: 06/15/2023]
Abstract
The study aims at looking into associations between the polymorphism rs6276 that occurs in the putative miRNA target site in the 3'UTR region of the DRD2 gene in patients with substance use disorder (SUD) comorbid with a maniacal syndrome (SUD MANIA). In our study, we did not state any essential difference in DRD2 rs6276 genotype frequencies in the studied samples of SUD MANIA, SUD, and control subjects. A significant result was found for the SUD MANIA group vs. SUD vs. controls on the Neuroticism Scale of NEO FFI test, and DRD2 rs6276 (p = 0.0320) accounted for 1.7% of the variance. The G/G homozygous variants were linked with lower results on the neuroticism scale in the SUD MANIA group because G/G alleles may serve a protective role in the expression of neuroticism in patients with SUD MANIA. So far, there have been no data in the literature on the relationship between the miRSNP rs6276 region in the DRD2 gene and neuroticism (personal traits) in patients with a diagnosis of substance use disorder comorbid with the affective, maniacal type disturbances related to SUD. This is the first report on this topic.
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Affiliation(s)
- Agnieszka Boroń
- Department of Clinical and Molecular Biochemistry, Pomeranian Medical University in Szczecin, Aleja Powstańców Wielkopolskich 72 St., 70-111 Szczecin, Poland
| | - Małgorzata Śmiarowska
- Department of Pharmacokinetics and Therapeutic Drug Monitoring, Pomeranian Medical University in Szczecin, Aleja Powstańcόw Wielkopolskich 72 St., 70-111 Szczecin, Poland
| | - Anna Grzywacz
- Independent Laboratory of Health Promotion, Pomeranian Medical University in Szczecin, Aleja Powstańcόw Wielkopolskich 72 St., 70-111 Szczecin, Poland
| | - Krzysztof Chmielowiec
- Department of Hygiene and Epidemiology, Collegium Medicum, University of Zielona Góra, Zyty 28 St., 65-046 Zielona Gora, Poland
| | - Jolanta Chmielowiec
- Department of Hygiene and Epidemiology, Collegium Medicum, University of Zielona Góra, Zyty 28 St., 65-046 Zielona Gora, Poland
| | - Jolanta Masiak
- Second Department of Psychiatry and Psychiatric Rehabilitation, Medical University of Lublin, Głuska 1 St., 20-059 Lublin, Poland
| | - Tomasz Pawłowski
- Division of Psychotherapy and Psychosomatic Medicine, Wroclaw Medical University, Wyb. L. Pasteura 10 St., 50-367 Wroclaw, Poland
| | - Dariusz Larysz
- 109 Military Hospital with Cutpatient Cinic in Szczecin, Piotra Skargi 9-11 St., 70-965 Szczecin, Poland
| | - Andrzej Ciechanowicz
- Department of Clinical and Molecular Biochemistry, Pomeranian Medical University in Szczecin, Aleja Powstańców Wielkopolskich 72 St., 70-111 Szczecin, Poland
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Arciniegas Ruiz SM, Eldar-Finkelman H. Glycogen Synthase Kinase-3 Inhibitors: Preclinical and Clinical Focus on CNS-A Decade Onward. Front Mol Neurosci 2022; 14:792364. [PMID: 35126052 PMCID: PMC8813766 DOI: 10.3389/fnmol.2021.792364] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 12/07/2021] [Indexed: 12/11/2022] Open
Abstract
The protein kinase, GSK-3, participates in diverse biological processes and is now recognized a promising drug discovery target in treating multiple pathological conditions. Over the last decade, a range of newly developed GSK-3 inhibitors of diverse chemotypes and inhibition modes has been developed. Even more conspicuous is the dramatic increase in the indications that were tested from mood and behavior disorders, autism and cognitive disabilities, to neurodegeneration, brain injury and pain. Indeed, clinical and pre-clinical studies were largely expanded uncovering new mechanisms and novel insights into the contribution of GSK-3 to neurodegeneration and central nerve system (CNS)-related disorders. In this review we summarize new developments in the field and describe the use of GSK-3 inhibitors in the variety of CNS disorders. This remarkable volume of information being generated undoubtedly reflects the great interest, as well as the intense hope, in developing potent and safe GSK-3 inhibitors in clinical practice.
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Zhang C, Xiao X, Li T, Li M. Translational genomics and beyond in bipolar disorder. Mol Psychiatry 2021; 26:186-202. [PMID: 32424235 DOI: 10.1038/s41380-020-0782-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 05/05/2020] [Accepted: 05/07/2020] [Indexed: 02/08/2023]
Abstract
Genome-wide association studies (GWAS) have revealed multiple genomic loci conferring risk of bipolar disorder (BD), providing hints for its underlying pathobiology. However, there are still remaining questions to answer. For example, discordance exists between BD heritability estimated with earlier epidemiological evidence and that calculated based on common GWAS variations. Where is the "missing heritability"? How can we explain the biology of the disease based on genetic findings? In this review, we summarize the accomplishments and limitations of current BD GWAS, and discuss potential reasons for the "missing heritability." In addition, progresses of research for the biological mechanisms underlying BD genetic risk using brain tissues, reprogrammed cells, and model animals are reviewed. While our knowledge of BD genetic basis is significantly promoted by these efforts, the complexities of gene regulation in the genome, the spatial-temporal heterogeneity during brain development, and the limitations of different experimental models should always be considered. Notably, several genes have been widely studied given their relatively well-characterized involvement in BD (e.g., CACAN1C and ANK3), and findings of these genes are summarized to both outline possible biological mechanisms of BD and describe examples of translating GWAS discoveries into the pathophysiology.
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Affiliation(s)
- Chen Zhang
- Division of Mood Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiao Xiao
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences and Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Tao Li
- Mental Health Center and Psychiatric Laboratory, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, Sichuan, China. .,West China Brain Research Center, West China Hospital of Sichuan University, Chengdu, Sichuan, China.
| | - Ming Li
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences and Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China.
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Lithium for schizophrenia: supporting evidence from a 12-year, nationwide health insurance database and from Akt1-deficient mouse and cellular models. Sci Rep 2020; 10:647. [PMID: 31959776 PMCID: PMC6971245 DOI: 10.1038/s41598-019-57340-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 12/19/2019] [Indexed: 12/11/2022] Open
Abstract
Accumulating evidence suggests AKT1 and DRD2-AKT-GSK3 signaling involvement in schizophrenia. AKT1 activity is also required for lithium, a GSK3 inhibitor, to modulate mood-related behaviors. Notably, GSK3 inhibitor significantly alleviates behavioral deficits in Akt1−/− female mice, whereas typical/atypical antipsychotics have no effect. In agreement with adjunctive therapy with lithium in treating schizophrenia, our data mining indicated that the average utilization rates of lithium in the Taiwan National Health Insurance Research Database from 2002 to 2013 are 10.9% and 6.63% in inpatients and outpatients with schizophrenia, respectively. Given that lithium is commonly used in clinical practice, it is of great interest to evaluate the effect of lithium on alleviating Akt1-related deficits. Taking advantage of Akt1+/− mice to mimic genetic deficiency in patients, behavioral impairments were replicated in female Akt1+/− mice but were alleviated by subchronic lithium treatment for 13 days. Lithium also effectively alleviated the observed reduction in phosphorylated GSK3α/β expression in the brains of Akt1+/− mice. Furthermore, inhibition of Akt expression using an Akt1/2 inhibitor significantly reduced neurite length in P19 cells and primary hippocampal cell cultures, which was also ameliorated by lithium. Collectively, our findings implied the therapeutic potential of lithium and the importance of the AKT1-GSK3 signaling pathway.
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Murphy E, Benítez-Burraco A. Toward the Language Oscillogenome. Front Psychol 2018; 9:1999. [PMID: 30405489 PMCID: PMC6206218 DOI: 10.3389/fpsyg.2018.01999] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 09/28/2018] [Indexed: 12/20/2022] Open
Abstract
Language has been argued to arise, both ontogenetically and phylogenetically, from specific patterns of brain wiring. We argue that it can further be shown that core features of language processing emerge from particular phasal and cross-frequency coupling properties of neural oscillations; what has been referred to as the language ‘oscillome.’ It is expected that basic aspects of the language oscillome result from genetic guidance, what we will here call the language ‘oscillogenome,’ for which we will put forward a list of candidate genes. We have considered genes for altered brain rhythmicity in conditions involving language deficits: autism spectrum disorders, schizophrenia, specific language impairment and dyslexia. These selected genes map on to aspects of brain function, particularly on to neurotransmitter function. We stress that caution should be adopted in the construction of any oscillogenome, given the range of potential roles particular localized frequency bands have in cognition. Our aim is to propose a set of genome-to-language linking hypotheses that, given testing, would grant explanatory power to brain rhythms with respect to language processing and evolution.
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Affiliation(s)
- Elliot Murphy
- Division of Psychology and Language Sciences, University College London, London, United Kingdom.,Department of Psychology, University of Westminster, London, United Kingdom
| | - Antonio Benítez-Burraco
- Department of Spanish Language, Linguistics and Literary Theory, University of Seville, Seville, Spain
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Weinstein JJ, van de Giessen E, Rosengard RJ, Xu X, Ojeil N, Brucato G, Gil RB, Kegeles LS, Laruelle M, Slifstein M, Abi-Dargham A. PET imaging of dopamine-D2 receptor internalization in schizophrenia. Mol Psychiatry 2018; 23:1506-1511. [PMID: 28507321 PMCID: PMC5690884 DOI: 10.1038/mp.2017.107] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 03/22/2017] [Accepted: 04/04/2017] [Indexed: 02/07/2023]
Abstract
Recent genetic, molecular and post-mortem studies suggest impaired dopamine (DA)-D2 receptor (D2R) trafficking in patients with schizophrenia (SZ). Imaging and preclinical studies have shown agonist-induced D2R internalization can be imaged with positron emission tomography (PET) using D2R radiotracers combined with psychostimulant challenge. This is feasible if radiotracer binding is measured when postchallenge DA levels have returned to baseline, following the initial competition phase between DA and radiotracer for binding to D2R. Here we used 'late-phase' imaging after challenge to test the hypothesis that impaired D2R internalization in SZ leads to blunted late-phase displacement, or a faster return to baseline, in patients compared with healthy controls (HCs). We imaged 10 patients with SZ and 9 HCs with PET and [11C]raclopride at baseline and two times (3-5 and 6-10 h) following 0.5 mg kg-1 dextroamphetamine. We measured binding potential relative to non-displaceable compartment (BPND) and derived percent reduction from baseline (ΔBPND) for each postamphetamine scan. To test the hypothesis that time course of return of striatal BPND to baseline differed between SZ and HCs, we implemented a linear model with ΔBPND as dependent variable, time after amphetamine as repeated measure and time after amphetamine and diagnostic group as fixed effects. Neither diagnostic group nor interaction of diagnostic group-by-time after amphetamine significantly affected striatal ΔBPND (F=1.38, P=0.26; F=0.51, P=0.61). These results show similar pattern of return of BPND to baseline as a function of time in patients with SZ and HC, suggesting that striatal D2R internalization as measured by our imaging paradigm is normal in patients with SZ.
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Affiliation(s)
- Jodi J. Weinstein
- Department of Psychiatry, Stony Brook University School of Medicine, Stony Brook, New York,Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, New York
| | | | | | - Xiaoyan Xu
- New York State Psychiatric Institute, New York, New York
| | - Najate Ojeil
- New York State Psychiatric Institute, New York, New York
| | - Gary Brucato
- Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, New York,New York State Psychiatric Institute, New York, New York
| | - Roberto B. Gil
- Department of Psychiatry, Stony Brook University School of Medicine, Stony Brook, New York
| | - Lawrence S. Kegeles
- Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, New York,New York State Psychiatric Institute, New York, New York
| | - Marc Laruelle
- Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, New York
| | - Mark Slifstein
- Department of Psychiatry, Stony Brook University School of Medicine, Stony Brook, New York
| | - Anissa Abi-Dargham
- Department of Psychiatry, Stony Brook University School of Medicine, Stony Brook, New York
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7
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Forouzanfar N, Baranova A, Milanizadeh S, Heravi-Moussavi A, Jebelli A, Abbaszadegan MR. Novel candidate genes may be possible predisposing factors revealed by whole exome sequencing in familial esophageal squamous cell carcinoma. Tumour Biol 2017; 39:1010428317699115. [PMID: 28459198 DOI: 10.1177/1010428317699115] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Esophageal squamous cell carcinoma is one of the deadliest of all the cancers. Its metastatic properties portend poor prognosis and high rate of recurrence. A more advanced method to identify new molecular biomarkers predicting disease prognosis can be whole exome sequencing. Here, we report the most effective genetic variants of the Notch signaling pathway in esophageal squamous cell carcinoma susceptibility by whole exome sequencing. We analyzed nine probands in unrelated familial esophageal squamous cell carcinoma pedigrees to identify candidate genes. Genomic DNA was extracted and whole exome sequencing performed to generate information about genetic variants in the coding regions. Bioinformatics software applications were utilized to exploit statistical algorithms to demonstrate protein structure and variants conservation. Polymorphic regions were excluded by false-positive investigations. Gene-gene interactions were analyzed for Notch signaling pathway candidates. We identified novel and damaging variants of the Notch signaling pathway through extensive pathway-oriented filtering and functional predictions, which led to the study of 27 candidate novel mutations in all nine patients. Detection of the trinucleotide repeat containing 6B gene mutation (a slice site alteration) in five of the nine probands, but not in any of the healthy samples, suggested that it may be a susceptibility factor for familial esophageal squamous cell carcinoma. Noticeably, 8 of 27 novel candidate gene mutations (e.g. epidermal growth factor, signal transducer and activator of transcription 3, MET) act in a cascade leading to cell survival and proliferation. Our results suggest that the trinucleotide repeat containing 6B mutation may be a candidate predisposing gene in esophageal squamous cell carcinoma. In addition, some of the Notch signaling pathway genetic mutations may act as key contributors to esophageal squamous cell carcinoma.
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Affiliation(s)
- Narjes Forouzanfar
- 1 Medical Genetics Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Ancha Baranova
- 2 School of System Biology, George Mason University, Fairfax, VA, USA
| | - Saman Milanizadeh
- 1 Medical Genetics Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Amir Jebelli
- 1 Medical Genetics Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mohammad Reza Abbaszadegan
- 1 Medical Genetics Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,4 Division of Human Genetics, Immunology Research Center, Avicenna Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran
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8
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New Repeat Polymorphism in the AKT1 Gene Predicts Striatal Dopamine D2/D3 Receptor Availability and Stimulant-Induced Dopamine Release in the Healthy Human Brain. J Neurosci 2017; 37:4982-4991. [PMID: 28416594 DOI: 10.1523/jneurosci.3155-16.2017] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 03/31/2017] [Accepted: 04/05/2017] [Indexed: 12/21/2022] Open
Abstract
The role of the protein kinase Akt1 in dopamine neurotransmission is well recognized and has been implicated in schizophrenia and psychosis. However, the extent to which variants in the AKT1 gene influence dopamine neurotransmission is not well understood. Here we investigated the effect of a newly characterized variant number tandem repeat (VNTR) polymorphism in AKT1 [major alleles: L- (eight repeats) and H- (nine repeats)] on striatal dopamine D2/D3 receptor (DRD2) availability and on dopamine release in healthy volunteers. We used PET and [11C]raclopride to assess baseline DRD2 availability in 91 participants. In 54 of these participants, we also measured intravenous methylphenidate-induced dopamine release to measure dopamine release. Dopamine release was quantified as the difference in specific binding of [11C]raclopride (nondisplaceable binding potential) between baseline values and values following methylphenidate injection. There was an effect of AKT1 genotype on DRD2 availability at baseline for the caudate (F(2,90) = 8.2, p = 0.001) and putamen (F(2,90) = 6.6, p = 0.002), but not the ventral striatum (p = 0.3). For the caudate and putamen, LL showed higher DRD2 availability than HH; HL were in between. There was also a significant effect of AKT1 genotype on dopamine increases in the ventral striatum (F(2,53) = 5.3, p = 0.009), with increases being stronger in HH > HL > LL. However, no dopamine increases were observed in the caudate (p = 0.1) or putamen (p = 0.8) following methylphenidate injection. Our results provide evidence that the AKT1 gene modulates both striatal DRD2 availability and dopamine release in the human brain, which could account for its association with schizophrenia and psychosis. The clinical relevance of the newly characterized AKT1 VNTR merits investigation.SIGNIFICANCE STATEMENT The AKT1 gene has been implicated in schizophrenia and psychosis. This association is likely to reflect modulation of dopamine signaling by Akt1 kinase since striatal dopamine hyperstimulation is associated with psychosis and schizophrenia. Here, using PET with [11C]raclopride, we identified in the AKT1 gene a new variable number tandem repeat (VNTR) marker associated with baseline striatal dopamine D2/D3 receptor availability and with methylphenidate-induced striatal dopamine increases in healthy volunteers. Our results confirm the involvement of the AKT1 gene in modulating striatal dopamine signaling in the human brain. Future studies are needed to assess the association of this new VNTR AKT1 variant in schizophrenia and drug-induced psychoses.
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Prats C, Arias B, Moya-Higueras J, Pomarol-Clotet E, Parellada M, González-Pinto A, Peralta V, Ibáñez MI, Martín M, Fañanás L, Fatjó-Vilas M. Evidence of an epistatic effect between Dysbindin-1 and Neuritin-1 genes on the risk for schizophrenia spectrum disorders. Eur Psychiatry 2016; 40:60-64. [PMID: 27855309 DOI: 10.1016/j.eurpsy.2016.07.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 07/20/2016] [Accepted: 07/20/2016] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND The interest in studying gene-gene interactions is increasing for psychiatric diseases such as schizophrenia-spectrum disorders (SSD), where multiple genes are involved. Dysbindin-1 (DTNBP1) and Neuritin-1 (NRN1) genes have been previously associated with SSD and both are involved in synaptic plasticity. We aimed to study whether these genes show an epistatic effect on the risk for SSD. METHODS The sample comprised 388 SSD patients and 397 healthy subjects. Interaction was tested between: (i) three DTNBP1 SNPs (rs2619537, rs2743864, rs1047631) related to changes in gene expression; and (ii) an haplotype in NRN1 previously associated with the risk for SSD (rs645649-rs582262: HAP-risk C-C). RESULTS An interaction between DTNBP1 rs2743864 and NRN1 HAP-risk was detected by using the model based multifactor dimensionality reduction (MB-MDR) approach (P=0.0049, after permutation procedure), meaning that the risk for SSD is significantly higher in those subjects carrying both the A allele of rs2743864 and the HAP-risk C-C. This interaction was confirmed by using a logistic regression model (P=0.033, OR (95%CI)=2.699 (1.08-6.71), R2=0.162). DISCUSSION Our results suggest that DTNBP1 and NRN1 genes show a joint effect on the risk for SSD. Although the precise mechanism underlying this effect is unclear, the fact that these genes have been involved in synaptic maturation, connectivity and glutamate signalling suggests that our findings could be of value as a link to the schizophrenia aetiology.
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Affiliation(s)
- C Prats
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals. Facultat de Biologia, Universitat de Barcelona, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Barcelona, Spain; Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain
| | - B Arias
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals. Facultat de Biologia, Universitat de Barcelona, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Barcelona, Spain; Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain
| | - J Moya-Higueras
- Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain; Department of Psychology, Faculty of Education, Psychology and Social Work, University of Lleida, Spain
| | - E Pomarol-Clotet
- Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain; FIDMAG Germanes Hospitalàries Research Foundation, Barcelona, Spain
| | - M Parellada
- Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain; Servicio de Psiquiatría del Niño y del Adolescente, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Instituto de Investigación Sanitaria del Hospital Gregorio Marañón (IiSGM), Madrid, Spain; Departamento de Psiquiatría, Facultad de Medicina, Universidad Complutense, Madrid, Spain
| | - A González-Pinto
- Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain; BIOARABA Health Research Institute, OSI Araba, University Hospital, Psychiatry Service, University of the Basque Country (EHU/UPV), Vitoria, Spain
| | - V Peralta
- Servicio de Psiquiatría, Complejo Hospitalario de Navarra, Pamplona, Spain; Instituto de Investigación Sanitaria de Navarra (IdiSNA), Pamplona, Spain
| | - M I Ibáñez
- Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain; Department of Basic and Clinical Psychology and Psychobiology, Universitat Jaume I, Castelló, Spain
| | - M Martín
- Adolescent Unit, CASM Benito Menni, Sant Boi de Llobregat, Spain
| | - L Fañanás
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals. Facultat de Biologia, Universitat de Barcelona, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Barcelona, Spain; Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain
| | - M Fatjó-Vilas
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals. Facultat de Biologia, Universitat de Barcelona, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Barcelona, Spain; Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain; FIDMAG Germanes Hospitalàries Research Foundation, Barcelona, Spain.
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10
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Chang CY, Chen YW, Wang TW, Lai WS. Akting up in the GABA hypothesis of schizophrenia: Akt1 deficiency modulates GABAergic functions and hippocampus-dependent functions. Sci Rep 2016; 6:33095. [PMID: 27615800 PMCID: PMC5018883 DOI: 10.1038/srep33095] [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: 05/10/2016] [Accepted: 08/19/2016] [Indexed: 12/29/2022] Open
Abstract
Accumulating evidence implies that both AKT1 and GABAA receptor (GABAAR) subunit genes are involved in schizophrenia pathogenesis. Activated Akt promotes GABAergic neuron differentiation and increases GABAAR expression on the plasma membrane. To elucidate the role of Akt1 in modulating GABAergic functions and schizophrenia-related cognitive deficits, a set of 6 in vitro and in vivo experiments was conducted. First, an Akt1/2 inhibitor was applied to evaluate its effect on GABAergic neuron-like cell formation from P19 cells. Inhibiting Akt resulted in a reduction in parvalbumin-positive neuron-like cells. In Akt1−/− and wild-type mice, seizures induced using pentylenetetrazol (a GABAAR antagonist) were measured, and GABAAR expression and GABAergic interneuron abundance in the brain were examined. Female Akt1−/− mice, but not male Akt1−/− mice, exhibited less pentylenetetrazol-induced convulsive activity than their corresponding wild-type controls. Reduced parvalbumin-positive interneuron abundance and GABAAR subunit expression, especially in the hippocampus, were also observed in female Akt1−/− mice compared to female wild-type mice. Neuromorphometric analyses revealed significantly reduced neurite complexity in hippocampal pyramidal neurons. Additionally, female Akt1−/− mice displayed increased hippocampal oscillation power and impaired spatial memory compared to female wild-type mice. Our findings suggest that Akt1 deficiency modulates GABAergic interneurons and GABAAR expression, contributing to hippocampus-dependent cognitive functional impairment.
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Affiliation(s)
- Chia-Yuan Chang
- Department of Psychology, National Taiwan University, Taipei, Taiwan
| | - Yi-Wen Chen
- Department of Psychology, National Taiwan University, Taipei, Taiwan
| | - Tsu-Wei Wang
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Wen-Sung Lai
- Department of Psychology, National Taiwan University, Taipei, Taiwan.,Graduate Institute of Brain and Mind Sciences, National Taiwan University, Taipei, Taiwan.,Neurobiology and Cognitive Science Center, National Taiwan University, Taipei, Taiwan
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11
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Fusar-Poli P, Meyer-Lindenberg A. Forty years of structural imaging in psychosis: promises and truth. Acta Psychiatr Scand 2016; 134:207-24. [PMID: 27404479 DOI: 10.1111/acps.12619] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/09/2016] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Since the first study published in the Lancet in 1976, structural neuroimaging has been used in psychosis with the promise of imminent clinical utility. The actual impact of structural neuroimaging in psychosis is still unclear. METHOD We present here a critical review of studies involving structural magnetic resonance imaging techniques in patients with psychosis published between 1976 and 2015 in selected journals of relevance for the field. For each study, we extracted summary descriptive variables. Additionally, we qualitatively described the main structural findings of each article in summary notes and we employed a biomarker rating system based on quality of evidence (scored 1-4) and effect size (scored 1-4). RESULTS Eighty studies meeting the inclusion criteria were retrieved. The number of studies increased over time, reflecting an increased structural imaging research in psychosis. However, quality of evidence was generally impaired by small samples and unclear biomarker definitions. In particular, there was little attempt of replication of previous findings. The effect sizes ranged from small to modest. No diagnostic or prognostic biomarker for clinical use was identified. CONCLUSIONS Structural neuroimaging in psychosis research has not yet delivered on the clinical applications that were envisioned.
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Affiliation(s)
- P Fusar-Poli
- Institute of Psychiatry Psychology Neuroscience, King's College London, London, UK.,OASIS Clinic, SLaM NHS Foundation Trust, London, UK
| | - A Meyer-Lindenberg
- Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany
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Tseng PT, Chen YW, Chung W, Tu KY, Wang HY, Wu CK, Lin PY. Significant Effect of Valproate Augmentation Therapy in Patients With Schizophrenia: A Meta-analysis Study. Medicine (Baltimore) 2016; 95:e2475. [PMID: 26825886 PMCID: PMC5291556 DOI: 10.1097/md.0000000000002475] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Revised: 12/13/2015] [Accepted: 12/16/2015] [Indexed: 11/25/2022] Open
Abstract
Valproate is an anticonvulsant, which is also widely used for treating psychiatric disorders. Some clinical trials have demonstrated benefits of valproate augmentation therapy in schizophrenia. Previous meta-analysis showed inconsistent findings because of limited literature at that time. The aim of this study is to update the newer published data by conducting a meta-analysis of clinical efficacy of valproate augmentation therapy in patients with schizophrenia or schizoaffective disorder. Data sources include electronic research through platform of PubMed. Study eligibility criteria, participants, and interventions were as follows: the inclusion criteria included articles discussing comparisons of the treatment effect in schizophrenic patients treated with antipsychotic augmented with valproate and antipsychotics with/without placebo; articles on clinical trials in humans. The exclusion criteria were case reports or series and nonclinical trials. We compared the effect between antipsychotic treatment with valproate augmentation and antipsychotic monotherapy. Data from clinical trials were pooled by random-effects model, and possible confounding variables were examined through meta-regression and subgroup analysis. Data from 11 articles including 889 patients were included into current meta-analysis. We found patients treated with antipsychotics with valproate augmentation showed significantly more improvement in total psychopathology than those treated with antipsychotics only (P = 0.02). Results from open trials, but not from randomized controlled trials (P = 0.20), showed significant improvement (P = 0.01). In addition, the significance only persisted in the studies conducted with a shorter treatment duration (P < 0.001) rather than longer treatment duration (P = 0.23). There is no difference in the dropout rate between valproate augmentation and antipsychotic treatment only (P = 0.14). We could not perform a detailed meta-analysis for every category of antipsychotics, long-term effect, and safety profiles of valproate augmentation therapy in maintenance treatment, safety in pregnant patients, and subtype of schizophrenia. Our meta-analysis highlights the significantly better treatment effect with valproate augmentation therapy in patients with schizophrenia or schizoaffective disorder, and provides important evidence for supporting the practice of valproate augmentation therapy in these patients.
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Affiliation(s)
- Ping-Tao Tseng
- From the Department of Psychiatry, Tsyr-Huey Mental Hospital, Kaohsiung Jen-Ai's Home, Taiwan (P-TT, WC, K-YT, H-YW, C-KW); Department of Neurology, E-Da Hospital, Kaohsiung, Taiwan (Y-WC); Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan (P-YL); and Institute for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan (P-YL)
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Lindner E, Glatz W, Schwab C, El-Shabrawi Y, Mossböck G. Analysis of functional polymorphisms in apoptosis-related genes in primary open angle glaucoma. Mol Vis 2015; 21:1340-4. [PMID: 26788026 PMCID: PMC4704768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 12/28/2015] [Indexed: 11/26/2022] Open
Abstract
PURPOSE Glaucoma is a disease with high heritability in which the degradation of retinal ganglion cells occurs via apoptosis. Therefore, we investigated the role of four functional apoptosis-related gene variants (Akt1 rs1130233, Bax rs4645878, Fas rs223476, and FasL rs763110) in patients with primary open angle glaucoma. METHODS 334 patients with primary open angle glaucoma and 334 controls were recruited for this case-control study. The main outcome measures were genotype distribution and allelic frequencies determined with PCR. RESULTS After adjustment for multiple testing, no significant difference in either the genotype distribution or the allelic frequencies of any investigated gene variant was found. CONCLUSIONS Our findings indicate that the investigated gene polymorphisms are unlikely to be major risk factors for primary open angle glaucoma in Caucasian patients.
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mTORC2/rictor signaling disrupts dopamine-dependent behaviors via defects in striatal dopamine neurotransmission. J Neurosci 2015; 35:8843-54. [PMID: 26063917 PMCID: PMC4461689 DOI: 10.1523/jneurosci.0887-15.2015] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Disrupted neuronal protein kinase B (Akt) signaling has been associated with dopamine (DA)-related neuropsychiatric disorders, including schizophrenia, a devastating mental illness. We hypothesize that proper DA neurotransmission is therefore dependent upon intact neuronal Akt function. Akt is activated by phosphorylation of two key residues: Thr308 and Ser473. Blunted Akt phosphorylation at Ser473 (pAkt-473) has been observed in lymphocytes and postmortem brains of schizophrenia patients, and psychosis-prone normal individuals. Mammalian target of rapamycin (mTOR) complex 2 (mTORC2) is a multiprotein complex that is responsible for phosphorylation of Akt at Ser473 (pAkt-473). We demonstrate that mice with disrupted mTORC2 signaling in brain exhibit altered striatal DA-dependent behaviors, such as increased basal locomotion, stereotypic counts, and exaggerated response to the psychomotor effects of amphetamine (AMPH). Combining in vivo and ex vivo pharmacological, electrophysiological, and biochemical techniques, we demonstrate that the changes in striatal DA neurotransmission and associated behaviors are caused, at least in part, by elevated D2 DA receptor (D2R) expression and upregulated ERK1/2 activation. Haloperidol, a typical antipsychotic and D2R blocker, reduced AMPH hypersensitivity and elevated pERK1/2 to the levels of control animals. By viral gene delivery, we downregulated mTORC2 solely in the dorsal striatum of adult wild-type mice, demonstrating that striatal mTORC2 regulates AMPH-stimulated behaviors. Our findings implicate mTORC2 signaling as a novel pathway regulating striatal DA tone and D2R signaling.
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Shorter KR, Miller BH. Epigenetic mechanisms in schizophrenia. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2015; 118:1-7. [PMID: 25958205 DOI: 10.1016/j.pbiomolbio.2015.04.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 04/27/2015] [Accepted: 04/28/2015] [Indexed: 01/03/2023]
Abstract
Epigenetic modifications, including DNA methylation, histone modifications, and non-coding RNAs, have been implicated in a number of complex diseases. Schizophrenia and other major psychiatric and neurodevelopmental disorders are associated with abnormalities in multiple epigenetic mechanisms, resulting in altered gene expression during development and adulthood. Polymorphisms and copy number variants in schizophrenia risk genes contribute to the high heritability of the disease, but environmental factors that lead to epigenetic modifications may either reduce or exacerbate the expression of molecular and behavioral phenotypes associated with schizophrenia and related disorders. In the present paper, we will review the current understanding of molecular dysregulation in schizophrenia, including disruption of the dopamine, NMDA, and GABA signaling pathways, and discuss the role of epigenetic factors underlying disease pathology.
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Affiliation(s)
- Kimberly R Shorter
- McKnight Brain Institute and Departments of Psychiatry and Medicine, University of Florida College of Medicine, Gainesville, FL 32607, USA
| | - Brooke H Miller
- McKnight Brain Institute and Departments of Psychiatry and Medicine, University of Florida College of Medicine, Gainesville, FL 32607, USA.
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Brett ZH, Sheridan M, Humphreys K, Smyke A, Gleason MM, Fox N, Zeanah C, Nelson C, Drury S. A neurogenetics approach to defining differential susceptibility to institutional care. INTERNATIONAL JOURNAL OF BEHAVIORAL DEVELOPMENT 2015; 39:150-160. [PMID: 25663728 PMCID: PMC4317330 DOI: 10.1177/0165025414538557] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
An individual's neurodevelopmental and cognitive sequelae to negative early experiences may, in part, be explained by genetic susceptibility. We examined whether extreme differences in the early caregiving environment, defined as exposure to severe psychosocial deprivation associated with institutional care compared to normative rearing, interacted with a biologically informed genoset comprising BDNF (rs6265), COMT (rs4680), and SIRT1 (rs3758391) to predict distinct outcomes of neurodevelopment at age 8 (N = 193, 97 males and 96 females). Ethnicity was categorized as Romanian (71%), Roma (21%), unknown (7%), or other (1%). We identified a significant interaction between early caregiving environment (i.e., institutionalized versus never institutionalized children) and the a priori defined genoset for full-scale IQ, two spatial working memory tasks, and prefrontal cortex gray matter volume. Model validation was performed using a bootstrap resampling procedure. Although we hypothesized that the effect of this genoset would operate in a manner consistent with differential susceptibility, our results demonstrate a complex interaction where vantage susceptibility, diathesis stress, and differential susceptibility are implicated.
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Affiliation(s)
| | | | | | - Anna Smyke
- Tulane University School of Medicine, USA
| | | | | | | | - Charles Nelson
- Boston Children's Hospital and Harvard Medical School, USA
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17
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Williams SM. Epistasis in the risk of human neuropsychiatric disease. Methods Mol Biol 2015; 1253:71-93. [PMID: 25403528 DOI: 10.1007/978-1-4939-2155-3_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Neuropsychiatric disease represents the ideal class of disease to assess the role of epistasis, as more genes are expressed in the brain than in any other tissue. In this chapter, two well-studied neuropsychiatric diseases are examined, Alzheimer's disease (AD) and schizophrenia, which have been shown to have multiple and, often, replicated interactions that associate with clinical endpoints or related phenotypes. In each case, a single gene is represented in a plurality of epistatic interactions, apolipoprotein E (APOE) for AD and catechol-O-methyltransferase for schizophrenia. Interestingly, of the two, only APOE has clear-cut and consistent evidence for a marginal association. Unraveling the underlying reasons is important in understanding both genetic etiology and architecture as well as how to use genetics to provide better personalized treatments.
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Affiliation(s)
- Scott M Williams
- Department of Genetics, Institute of Quantitative Biomedical Sciences, Geisel School of Medicine, Dartmouth College, 78 College ST, HB 6044, Hanover, NH, 03755, USA,
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18
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Bhattacharyya S, Iyegbe C, Atakan Z, Martin-Santos R, Crippa JA, Xu X, Williams S, Brammer M, Rubia K, Prata D, Collier DA, McGuire PK. Protein kinase B (AKT1) genotype mediates sensitivity to cannabis-induced impairments in psychomotor control. Psychol Med 2014; 44:3315-3328. [PMID: 25065544 DOI: 10.1017/s0033291714000920] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND What determines inter-individual variability to impairments in behavioural control that may underlie road-traffic accidents, and impulsive and violent behaviours occurring under the influence of cannabis, the most widely used illicit drug worldwide? METHOD Employing a double-blind, repeated-measures design, we investigated the genetic and neural basis of variable sensitivity to cannabis-induced behavioural dyscontrol in healthy occasional cannabis users. Acute oral challenge with placebo or Δ9-tetrahydrocannabinol (THC), the main psychoactive ingredient in cannabis, was combined with functional magnetic resonance imaging, while participants performed a response inhibition task that involved inhibiting a pre-potent motor response. They were genotyped for rs1130233 single nucleotide polymorphisms (SNPs) of the protein kinase B (AKT1) gene. RESULTS Errors of inhibition were significantly (p = 0.008) increased following administration of THC in carriers of the A allele, but not in G allele homozygotes of the AKT1 rs1130233 SNP. The A allele carriers also displayed attenuation of left inferior frontal response with THC evident in the sample as a whole, while there was a modest enhancement of inferior frontal activation in the G homozygotes. There was a direct relationship (r = -0.327, p = 0.045) between the behavioural effect of THC and its physiological effect in the inferior frontal gyrus, where AKT1 genotype modulated the effect of THC. CONCLUSIONS These results require independent replication and show that differing vulnerability to acute psychomotor impairments induced by cannabis depends on variation in a gene that influences dopamine function, and is mediated through modulation of the effect of cannabis on the inferior frontal cortex, that is rich in dopaminergic innervation and critical for psychomotor control.
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Affiliation(s)
- S Bhattacharyya
- Department of Psychosis Studies,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - C Iyegbe
- Social, Genetic and Developmental Psychiatry Centre,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - Z Atakan
- Department of Psychosis Studies,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - R Martin-Santos
- Pharmacology Research Unit, IMIM-Hospital del Mar and Psychiatric Department,ICN,Hospital Clinico, Barcelona,Spain
| | - J A Crippa
- Department of Neurology, Psychiatry and Medical Psychology, Faculty of Medicine of Ribeirão Preto,University of São Paulo,Brazil
| | - X Xu
- Social, Genetic and Developmental Psychiatry Centre,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - S Williams
- Department of Neuroimaging, Centre for Neuroimaging Sciences,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - M Brammer
- Department of Neuroimaging, Centre for Neuroimaging Sciences,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - K Rubia
- Department of Child and Adolescent Psychiatry,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - D Prata
- Department of Psychosis Studies,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - D A Collier
- Social, Genetic and Developmental Psychiatry Centre,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - P K McGuire
- Department of Psychosis Studies,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
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Lavoie J, Hébert M, Beaulieu JM. Glycogen synthase kinase-3 overexpression replicates electroretinogram anomalies of offspring at high genetic risk for schizophrenia and bipolar disorder. Biol Psychiatry 2014; 76:93-100. [PMID: 24138923 DOI: 10.1016/j.biopsych.2013.08.035] [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: 08/05/2013] [Revised: 08/26/2013] [Accepted: 08/27/2013] [Indexed: 12/18/2022]
Abstract
BACKGROUND Electroretinogram (ERG) anomalies occur in patients with psychiatric disorders and represent potential biomarkers for diagnosis. For instance, decreased rod ERG (b-wave amplitude at Vmax) is a biological endophenotype in young offspring at high genetic risk (HR) for schizophrenia (SZ) and bipolar disorder (BD). Also, a decrease in cone a-wave and rod a- and b- wave was observed in SZ patients. However, the biological underpinning of these anomalies remains unknown. Several genetic variants associated with enhanced risk for SZ and/or BD can activate glycogen synthase kinase-3 isozymes (GSK3α and β). Here we examined the potential contribution of GSK3α and β in the modulation of the ERG. METHODS Cone and rod ERGs were recorded in mice having increased (prpGSK3β mice) or reduced (GSK3β(+/-) mice) GSK3β expression and in GSK3α knockout (KO) mice. RESULTS In prpGSK3β mice, we observed a decrease in rod b-wave amplitude at Vmax, whereas enhanced b-wave amplitude at Vmax was found in GSK3β(+/-) mice. An increase in cone a- and b-wave amplitude at Vmax and in rod b-wave amplitude at Vmax was observed in GSK3α-KO mice. CONCLUSIONS GSK3 expression modulates some ERG parameters. The phenotype observed in prpGSK3β mice is consistent with observations made in HRs. ERG anomalies observed in GSK3β(+/-) and GSK3α-KO mice confirm an association between the rod and cone b-wave amplitude and the expression of GSK3 isozymes. Changes in GSK3 expression or activity may explain some ERG anomalies in HRs and patients, thus supporting the biological validity of ERG measurements as a valuable biomarker for psychiatric research.
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Affiliation(s)
- Joëlle Lavoie
- Centre de Recherche de l'Institut Universitaire en Santé Mentale de Québec, Quebec City, Canada; Departments of Psychiatry and Neuroscience and Ophthalmology, Otorhinolaryngology, Quebec City, Canada; Cervico-Facial Surgery, Faculty of Medicine, Université Laval, Quebec City, Canada
| | - Marc Hébert
- Centre de Recherche de l'Institut Universitaire en Santé Mentale de Québec, Quebec City, Canada; Cervico-Facial Surgery, Faculty of Medicine, Université Laval, Quebec City, Canada
| | - Jean-Martin Beaulieu
- Centre de Recherche de l'Institut Universitaire en Santé Mentale de Québec, Quebec City, Canada; Departments of Psychiatry and Neuroscience and Ophthalmology, Otorhinolaryngology, Quebec City, Canada.
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20
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Viviani R, Lehmann ML, Stingl JC. Use of magnetic resonance imaging in pharmacogenomics. Br J Clin Pharmacol 2014; 77:684-94. [PMID: 23802603 PMCID: PMC3971984 DOI: 10.1111/bcp.12197] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 06/18/2013] [Indexed: 01/11/2023] Open
Abstract
Because of the large variation in the response to psychoactive medication, many studies have attempted to uncover genetic factors that determine response. While considerable knowledge exists on the large effects of genetic polymorphisms on pharmacokinetics and plasma concentrations of drugs, effects of the concentration at the target site and pharmacodynamic effects on brain functions in disease are much less known. This article reviews the role of magnetic resonance imaging (MRI) to visualize response to medication in brain behaviour circuits in vivo in humans and assess the influence of pharmacogenetic factors. Two types of studies have been used to characterize effects of medication and genetic variation. In task-related activation studies the focus is on changes in the activity of a neural circuit associated with a specific psychological process. The second type of study investigates resting state perfusion. These studies provide an assessment of vascular changes associated with bioavailability of drugs in the brain, but may also assess changes in neural activity after binding of centrally active agents. Task-related pharmacogenetic studies of cognitive function have characterized the effects in the prefrontal cortex of genetic polymorphisms of dopamine receptors (DRD2), metabolic enzymes (COMT) and in the post-synaptic signalling cascade under the administration of dopamine agonists and antagonists. In contrast, pharmacogenetic imaging with resting state perfusion is still in its infancy. However, the quantitative nature of perfusion imaging, its non-invasive character and its repeatability might be crucial assets in visualizing the effects of medication in vivo in man during therapy.
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Affiliation(s)
- Roberto Viviani
- Department of Psychiatry and Psychotherapy III, University of Ulm, Ulm, Germany; Institute of Psychology, University of Innsbruck, Innsbruck, Austria
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Abstract
Psychosis is an abnormal mental state characterized by disorganization, delusions and hallucinations. Animal models have become an increasingly important research tool in the effort to understand both the underlying pathophysiology and treatment of psychosis. There are multiple animal models for psychosis, with each formed by the coupling of a manipulation and a measurement. In this manuscript we do not address the diseases of which psychosis is a prominent comorbidity. Instead, we summarize the current state of affairs and future directions for animal models of psychosis. To accomplish this, our manuscript will first discuss relevant behavioral and electrophysiological measurements. We then provide an overview of the different manipulations that are combined with these measurements to produce animal models. The strengths and limitations of each model will be addressed in order to evaluate its cross-species comparability.
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Effect of COMT Val108/158Met genotype on risk for polydipsia in chronic patients with schizophrenia. Neuromolecular Med 2014; 16:398-404. [PMID: 24443099 DOI: 10.1007/s12017-014-8287-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 01/06/2014] [Indexed: 10/25/2022]
Abstract
Polydipsia is a serious condition often seen among patients with schizophrenia (SCZ). The cause of polydipsia is unknown; hence, it is hard to treat or manage. Animal studies showed that the drinking behavior is regulated by central dopaminergic neurotransmission at the hypothalamus. Meanwhile, the existence of a genetic predisposition to polydipsia in patients with SCZ has been suggested. The purpose of this study was to assess whether a functional polymorphism, Val(108/158)Met in the gene for catechol-O-methyltransferase (COMT), is associated with susceptibility to polydipsia using a Japanese sample of SCZ. Our sample includes 330 chronic patients with SCZ (83 polydipsic patients and 247 non-polydipsic controls). The common COMT Val(108/158)Met polymorphism was genotyped, and the differences in genotype distribution and allele frequency between cases and controls were evaluated using the χ(2) test. A significant association between the COMT Val(108/158)Met polymorphism and polydipsia was found (genotype distribution: χ(2) = 13.0, df = 2, p = 0.001; allele frequency: χ(2) = 7.50, df = 1, p = 0.006). The high-COMT activity group (Val/Val) was more frequent among patients with polydipsia compared with the low-COMT activity group (Val/Met + Met/Met) [odds ratio (OR) = 2.46]. The association survived after controlling for other possible confounding factors, including gender, age, age of onset, current antipsychotic dose, and smoking status. Our results suggest that the COMT Val(108/158)Met genotype may confer susceptibility to polydipsia in SCZ. To our knowledge, this is the first association study between the COMT gene and polydipsia in SCZ. Further studies with larger sample sizes are warranted to confirm present findings.
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Effect of the BDNF Val66Met polymorphism on regional gray matter volumes and cognitive function in the Chinese population. Neuromolecular Med 2013; 16:127-36. [PMID: 24366608 DOI: 10.1007/s12017-013-8265-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 09/10/2013] [Indexed: 10/25/2022]
Abstract
The brain-derived neurotrophic factor (BDNF) Val66Met polymorphism is common and influences the activity-dependent secretion of BDNF, which is critical for neuronal plasticity and survival. This study investigated the genetic effect of the BDNF Val66Met polymorphism on cognitive function and regional gray matter (GM) volume in a healthy Chinese population (n = 330). Voxel-based morphometry (VBM)-optimized analysis was used. There was no significant difference in the neuropsychological performances among the three BDNF genotypic groups. VBM analyses demonstrated that Met homozygotes had greater GM volumes than Val homozygotes in the left medial frontal gyrus, the left middle temporal gyrus, the left cerebellum, and the right middle temporal gyrus, and had larger GM volumes than Val/Met heterozygotes in the left middle temporal gyrus, the left inferior temporal gyrus, and the right superior frontal gyrus. Our findings suggest that the presence of two Met alleles has a protective effect on regional GM volumes in the Chinese population.
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Siebenhühner F, Weiss SA, Coppola R, Weinberger DR, Bassett DS. Intra- and inter-frequency brain network structure in health and schizophrenia. PLoS One 2013; 8:e72351. [PMID: 23991097 PMCID: PMC3753323 DOI: 10.1371/journal.pone.0072351] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Accepted: 07/08/2013] [Indexed: 01/22/2023] Open
Abstract
Empirical studies over the past two decades have provided support for the hypothesis that schizophrenia is characterized by altered connectivity patterns in functional brain networks. These alterations have been proposed as genetically mediated diagnostic biomarkers and are thought to underlie altered cognitive functions such as working memory. However, the nature of this dysconnectivity remains far from understood. In this study, we perform an extensive analysis of functional connectivity patterns extracted from MEG data in 14 subjects with schizophrenia and 14 healthy controls during a 2-back working memory task. We investigate uni-, bi- and multivariate properties of sensor time series by computing wavelet entropy of and correlation between time series, and by constructing binary networks of functional connectivity both within and between classical frequency bands ([Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text]). Networks are based on the mutual information between wavelet time series, and estimated for each trial window separately, enabling us to consider both network topology and network dynamics. We observed significant decreases in time series entropy and significant increases in functional connectivity in the schizophrenia group in comparison to the healthy controls and identified an inverse relationship between these measures across both subjects and sensors that varied over frequency bands and was more pronounced in controls than in patients. The topological organization of connectivity was altered in schizophrenia specifically in high frequency [Formula: see text] and [Formula: see text] band networks as well as in the [Formula: see text]-[Formula: see text] cross-frequency networks. Network topology varied over trials to a greater extent in patients than in controls, suggesting disease-associated alterations in dynamic network properties of brain function. Our results identify signatures of aberrant neurophysiological behavior in schizophrenia across uni-, bi- and multivariate scales and lay the groundwork for further clinical studies that might lead to the discovery of new intermediate phenotypes.
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Affiliation(s)
- Felix Siebenhühner
- Department of Physics, University of California Santa Barbara, Santa Barbara, California, United States of America
- Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Shennan A. Weiss
- Department of Neurology, Columbia University, New York, New York, United States of America
| | - Richard Coppola
- MEG Core Facility, National Institute of Mental Health, Bethesda, Maryland, United States of America
| | - Daniel R. Weinberger
- Genes, Cognition and Psychosis Program, Clinical Brain Disorders Branch, National Institute of Mental Health, Bethesda, Maryland, United States of America
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, Maryland, United States of America
| | - Danielle S. Bassett
- Department of Physics, University of California Santa Barbara, Santa Barbara, California, United States of America
- Sage Center for the Study of the Mind, University of California Santa Barbara, Santa Barbara, California, United States of America
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25
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Featherstone RE, M Tatard-Leitman V, Suh JD, Lin R, Lucki I, Siegel SJ. Electrophysiological and behavioral responses to ketamine in mice with reduced Akt1 expression. Psychopharmacology (Berl) 2013; 227:639-49. [PMID: 23392353 PMCID: PMC3808977 DOI: 10.1007/s00213-013-2997-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 01/14/2013] [Indexed: 11/25/2022]
Abstract
RATIONALE A number of studies have associated reduced Akt1 expression with vulnerability for schizophrenia. Although mice with deletion of a single copy of the Akt1 gene (Akt1(+/-)) show reduced Akt1 expression relative to wild-type (WT) animals, the extent to which these mice show schizophrenia-like phenotypic changes and/or increased susceptibility to epigenetic or non-genetic factors related to schizophrenia is unknown. OBJECTIVES Mutant mice were assessed on electroencephalographic/event-related potential (EEG/ERP) and behavioral (acoustic startle and pre-pulse inhibition) measures relevant to schizophrenia. Mice were also assessed following exposure to the NMDA receptor antagonist ketamine, a potent psychotomimetic drug, in order to assess the role of reduced Akt1 expression as a vulnerability factor for schizophrenia. Methods Akt1(+/-), Akt1(-/-), and WT mice received a series of paired-click, white noise stimuli, following ketamine (50 mg/kg) and saline injections. EEG was analyzed for ERPs and event-related power. Akt1(+/-) and WT mice were also assessed on PPI following ketamine (50 mg/kg) or saline injection. RESULTS Akt1(+/-) and Akt1(-/-) mice displayed reduced amplitude of the P20 component of the ERP to the first click of a paired-click stimulus, as well as reduced S1-S2 difference for P20 and N40 components, following ketamine. Mutant mice also showed increased reduction in gamma synchrony and theta suppression following ketamine. Akt1(+/-) mice displayed reduced pre-pulse inhibition. CONCLUSIONS Reduced genetic expression of Akt1 facilitated ketamine-induced changes of EEG and behavior in mice, suggesting that reduced Akt1 expression can serve as a vulnerability factor for schizophrenia.
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Affiliation(s)
- Robert E Featherstone
- Department of Psychiatry, Translational Neuroscience Program, School of Medicine, University of Pennsylvania, 125 South 31st Street, Philadelphia, PA 19104, USA.
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Abstract
The BDNF Val(66)Met polymorphism, a possible risk variant for mental disorders, is a potent modulator of neural plasticity in humans and has been linked to deficits in gray matter structure, function, and cognition. The impact of the variant on brain white matter structure, however, is controversial and remains poorly understood. Here, we used diffusion tensor imaging to examine the effects of BDNF Val(66)Met genotype on white matter microstructure in a sample of 85 healthy Caucasian adults. We demonstrate decreases of fractional anisotropy and widespread increases in radial diffusivity in Val/Val homozygotes compared with Met-allele carriers, particularly in prefrontal and occipital pathways. These data provide an independent confirmation of prior imaging genetics work, are consistent with complex effects of the BDNF Val(66)Met polymorphism on human brain structure, and may serve to generate hypotheses about variation in white matter microstructure in mental disorders associated with this variant.
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Sullivan D, Pinsonneault JK, Papp AC, Zhu H, Lemeshow S, Mash DC, Sadee W. Dopamine transporter DAT and receptor DRD2 variants affect risk of lethal cocaine abuse: a gene-gene-environment interaction. Transl Psychiatry 2013; 3:e222. [PMID: 23340505 PMCID: PMC3566726 DOI: 10.1038/tp.2012.146] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Epistatic gene-gene interactions could contribute to the heritability of complex multigenic disorders, but few examples have been reported. Here, we focus on the role of aberrant dopaminergic signaling, involving the dopamine transporter DAT, a cocaine target, and the dopamine D2 receptor, which physically interacts with DAT. Splicing polymorphism rs2283265 of DRD2, encoding D2 receptors, were shown to confer risk of cocaine overdose/death (odds ratio ∼3) in subjects and controls from the Miami Dade County Brain Bank.(1) Risk of cocaine-related death attributable to the minor allele of rs2283265 was significantly enhanced to OR=7.5 (P=0.0008) in homozygous carriers of the main 6-repeat allele of DAT rs3836790, a regulatory VNTR in intron8 lacking significant effect itself. In contrast, carriers of the minor 5-repeat DAT allele showed no significant risk (OR=1.1, P=0.84). DAT rs3836790 and DRD2 rs2283265 also interacted by modulating DAT protein activity in the ventral putamen of cocaine abusers. In high-linkage disequilibrium with the VNTR, DAT rs6347 in exon9 yielded similar results. Assessing the impact of DAT alone, a rare DAT haplotype formed by the minor alleles of rs3836790 and rs27072, a regulatory DAT variant in the 3'-UTR, occurred in nearly one-third of the cocaine abusers but was absent in African American controls, apparently conferring strong risk. These results demonstrate gene-gene-drug interaction affecting risk of fatal cocaine intoxication.
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Affiliation(s)
- D Sullivan
- Department of Pharmacology and Program in Pharmacogenomics, The Ohio State University, Columbus, OH, USA,Department of Biostatistics, College of Public Health, The Ohio State University, Columbus, OH, USA
| | - J K Pinsonneault
- Department of Pharmacology and Program in Pharmacogenomics, The Ohio State University, Columbus, OH, USA
| | - A C Papp
- Department of Pharmacology and Program in Pharmacogenomics, The Ohio State University, Columbus, OH, USA
| | - H Zhu
- Department of Biostatistics, College of Public Health, The Ohio State University, Columbus, OH, USA
| | - S Lemeshow
- Department of Biostatistics, College of Public Health, The Ohio State University, Columbus, OH, USA
| | - D C Mash
- University of Miami School of Medicine, Departments of Neurology and Molecular and Cellular Pharmacology, Miami, FL, USA
| | - W Sadee
- Department of Pharmacology and Program in Pharmacogenomics, The Ohio State University, Columbus, OH, USA,Department of Biostatistics, College of Public Health, The Ohio State University, Columbus, OH, USA,Department of Pharmacology, Program in Pharmacogenomics, The Ohio State University, 333W. 10th Avenue, Columbus, OH 43210-1239, USA. E-mail
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28
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Abstract
Genome-wide association studies (GWAS) have demonstrated a significant polygenic contribution to bipolar disorder (BD) where disease risk is determined by the summation of many alleles of small individual magnitude. Modelling polygenic risk scores may be a powerful way of identifying disrupted brain regions whose genetic architecture is related to that of BD. We determined the extent to which common genetic variation underlying risk to BD affected neural activation during an executive processing/language task in individuals at familial risk of BD and healthy controls. Polygenic risk scores were calculated for each individual based on GWAS data from the Psychiatric GWAS Consortium Bipolar Disorder Working Group (PGC-BD) of over 16 000 subjects. The familial group had a significantly higher polygene score than the control group (P=0.04). There were no significant group by polygene interaction effects in terms of association with brain activation. However, we did find that an increasing polygenic risk allele load for BD was associated with increased activation in limbic regions previously implicated in BD, including the anterior cingulate cortex and amygdala, across both groups. The findings suggest that this novel polygenic approach to examine brain-imaging data may be a useful means of identifying genetically mediated traits mechanistically linked to the aetiology of BD.
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Tan HY, Chen AG, Kolachana B, Apud JA, Mattay VS, Callicott JH, Chen Q, Weinberger DR. Effective connectivity of AKT1-mediated dopaminergic working memory networks and pharmacogenetics of anti-dopaminergic treatment. ACTA ACUST UNITED AC 2012; 135:1436-45. [PMID: 22525159 DOI: 10.1093/brain/aws068] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Working memory is a limited capacity system that integrates and manipulates information across brief periods of time, engaging a network of prefrontal, parietal and subcortical brain regions. Genetic control of these heritable brain processes have been suggested by functional genetic variations influencing dopamine signalling, which affect prefrontal activity during complex working memory tasks. However, less is known about genetic control over component working memory cortical-subcortical networks in humans, and the pharmacogenetic implications of dopamine-related genes on cognition in patients receiving anti-dopaminergic drugs. Here, we examined predictions from basic models of dopaminergic signalling in cortical and cortical-subcortical circuitries implicated in dissociable working memory maintenance and manipulation processes. We also examined pharmacogenetic effects on cognition in the context of anti-dopaminergic drug therapy. Using dynamic causal models of functional magnetic resonance imaging in normal subjects (n = 46), we identified differentiated effects of functional polymorphisms in COMT, DRD2 and AKT1 genes on prefrontal-parietal and prefrontal-striatal circuits engaged during maintenance and manipulation, respectively. Cortical synaptic dopamine monitored by the COMT Val158Met polymorphism influenced prefrontal control of both parietal processing in working memory maintenance and striatal processing in working memory manipulation. DRD2 and AKT1 polymorphisms implicated in DRD2 signalling influenced only the prefrontal-striatal network associated with manipulation. In the context of anti-psychotic drugs, the DRD2 and AKT1 polymorphisms altered dose-response effects of anti-psychotic drugs on cognition in schizophrenia (n = 111). Thus, we suggest that genetic modulation of DRD2-AKT1-related prefrontal-subcortical circuits could at least in part influence cognitive dysfunction in psychosis and its treatment.
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Affiliation(s)
- Hao Yang Tan
- Clinical Brain Disorders Branch, Genes Cognition and Psychosis Program, Division of Intramural Research Programs, National Institute of Mental Health, Bethesda, MD 20892, USA.
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30
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Szamosi A, Kelemen O, Kéri S. Hippocampal volume and the AKT signaling system in first-episode schizophrenia. J Psychiatr Res 2012; 46:279-84. [PMID: 22209534 DOI: 10.1016/j.jpsychires.2011.12.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 12/09/2011] [Accepted: 12/12/2011] [Indexed: 12/31/2022]
Abstract
OBJECTIVE The phosphoinositide 3'-kinase (PI3K)--protein kinase B (AKT1)--glycogen synthase kinase (GSK)-3β system is modulated by several factors implicated in the pathophysiology of schizophrenia. Evidence suggests that neuregulin 1 (NRG1) induces decreased AKT phosphorylation in schizophrenia relative to healthy controls, which may be related to dysfunctional neurodevelopment and neuroplasticity. The aim of this study was to investigate the relationship between NRG1--induced AKT phosphorylation and hippocampal volume in schizophrenia. METHODS Participants were 20 first-episode patients with schizophrenia who did not receive psychotropic medications and 20 matched healthy controls. We measured the phosphorylated AKT--total AKT and phosphorylated ERK (extracellular signal-regulated kinase)--total ERK ratios in peripheral lymphoblasts before and after NRG1 administration. Whole-brain, left, and right hippocampal volumes were quantified using FreeSurfer software. RESULTS Patients with schizophrenia displayed decreased AKT but normal ERK ratio compared with controls. Patients also had a reduction in left hippocampal volume. There was no significant difference between patients and controls in whole-brain and right hippocampal volume. Decreased AKT ratio was associated with reduced hippocampal volume. There was no significant relationship between ERK ratio and brain structure. CONCLUSION Activation of the AKT system is specifically associated with hippocampal volume in first-episode schizophrenia, which provides further evidence for the pivotal role of this messenger system in the pathophysiology of psychotic disorders.
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Heck A, Vogler C, Gschwind L, Ackermann S, Auschra B, Spalek K, Rasch B, de Quervain D, Papassotiropoulos A. Statistical epistasis and functional brain imaging support a role of voltage-gated potassium channels in human memory. PLoS One 2011; 6:e29337. [PMID: 22216252 PMCID: PMC3244442 DOI: 10.1371/journal.pone.0029337] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Accepted: 11/25/2011] [Indexed: 11/18/2022] Open
Abstract
Despite the current progress in high-throughput, dense genome scans, a major portion of complex traits' heritability still remains unexplained, a phenomenon commonly termed “missing heritability.” The negligence of analytical approaches accounting for gene-gene interaction effects, such as statistical epistasis, is probably central to this phenomenon. Here we performed a comprehensive two-way SNP interaction analysis of human episodic memory, which is a heritable complex trait, and focused on 120 genes known to show differential, memory-related expression patterns in rat hippocampus. Functional magnetic resonance imaging was also used to capture genotype-dependent differences in memory-related brain activity. A significant, episodic memory-related interaction between two markers located in potassium channel genes (KCNB2 and KCNH5) was observed (Pnominal combined = 0.000001). The epistatic interaction was robust, as it was significant in a screening (Pnominal = 0.0000012) and in a replication sample (Pnominal = 0.01). Finally, we found genotype-dependent activity differences in the parahippocampal gyrus (Pnominal = 0.001) supporting the behavioral genetics finding. Our results demonstrate the importance of analytical approaches that go beyond single marker statistics of complex traits.
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Affiliation(s)
- Angela Heck
- Division of Molecular Neuroscience, Department of Psychology, University of Basel, Basel, Switzerland.
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