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Warner AK, Iskander L, Allen K, Quatela I, Borrelli H, Sachs BD. The effects of brain serotonin deficiency on the behavioral and neurogenesis-promoting effects of voluntary exercise in tryptophan hydroxylase 2 (R439H) knock-in mice. Neuropharmacology 2024; 258:110082. [PMID: 39009217 DOI: 10.1016/j.neuropharm.2024.110082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Revised: 07/11/2024] [Accepted: 07/12/2024] [Indexed: 07/17/2024]
Abstract
Exercise is known to reduce depression and anxiety symptoms. Although the cellular and molecular mechanisms underlying this effect remain unknown, exercise-induced increases in neurotransmitter release and hippocampal neurogenesis have been hypothesized to play key roles. One neurotransmitter that has been implicated in both antidepressant-like effects and the regulation of hippocampal neurogenesis is serotonin (5-HT). Complete loss of function of the brain 5-HT synthesis enzyme (tryptophan hydroxylase 2, Tph2) has been reported to prevent exercise-induced increases in neurogenesis and to block a subset of antidepressant-like responses to selective serotonin reuptake inhibitors (SSRIs), but whether partial loss of Tph2 function blocks the behavioral and neurogenic effects of exercise has not been established. This study used four tests that are predictive of antidepressant efficacy to determine the impact of 5-HT deficiency on responses to exercise in male and female mice. Our results demonstrate that low 5-HT impairs the behavioral effects of exercise in females in the forced swim and novelty-suppressed feeding tests. However, genetic reductions in 5-HT synthesis did not significantly impact exercise-induced alterations in cellular proliferation or immature neuron production in the hippocampus in either sex. These findings highlight the importance of brain 5-HT in mediating behavioral responses to exercise and suggest that individual differences in brain 5-HT synthesis could influence sensitivity to the mental health benefits of exercise. Furthermore, the observed disconnect between neurogenic and behavioral responses to exercise suggests that increased neurogenesis is unlikely to be the primary driver of the behavioral effects of exercise observed here.
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Affiliation(s)
- Allison K Warner
- Department of Psychological and Brain Sciences, Villanova University, USA
| | - Lauren Iskander
- Department of Psychological and Brain Sciences, Villanova University, USA
| | - Kristen Allen
- Department of Psychological and Brain Sciences, Villanova University, USA
| | - Isabella Quatela
- Department of Psychological and Brain Sciences, Villanova University, USA
| | - Hannah Borrelli
- Department of Psychological and Brain Sciences, Villanova University, USA
| | - Benjamin D Sachs
- Department of Psychological and Brain Sciences, Villanova University, USA.
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2
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Corzo-Gómez J, Picazo O, Castellanos-Pérez M, Briones-Aranda A. Systematic Review of the Serotonergic System in the Pathophysiology of Severe Dengue: The Theory of Thrombocytopenia and Vascular Extravasation. Mini Rev Med Chem 2023; 23:230-243. [PMID: 35726421 DOI: 10.2174/1389557522666220619231643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/27/2022] [Accepted: 04/29/2022] [Indexed: 11/22/2022]
Abstract
BACKGROUND Severe dengue is characterized by thrombocytopenia, hemorrhaging, and/or capillary extravasation and may be linked to a reduced plasma concentration of serotonin (5-hydroxytriptamine, or 5-HT). OBJECTIVE The aim of the current contribution was to conduct a systematic bibliographic review of reports on the role of the peripheral serotonergic system in the pathophysiology of severe dengue. METHODS A bibliographic review was carried out of in vivo/in vitro models, clinical trials, and case series studies from 2010-2019. The selective criteria were the use of treatments with serotonin reuptake inhibitors and/or agonists/antagonists of 5-HT receptors and their impact on inflammation, coagulation, and endothelium. Moreover, cross-sectional and cohort studies on the relationship between intraplatelet and plasma 5-HT levels in patients with dengue were also included. The risk of bias in the selected reports was examined with domain-based assessment utilizing Cochrane-type criteria. The main results are summarized in Tables and Figures. RESULTS Based on descriptions of the effect of serotonergic drugs on 5-HT levels and the findings of clinical trials of dengue treatment, most receptors of the peripheral serotonergic system, and especially 5-HT2A, seem to participate in regulating serum 5-HT during severe dengue. Therefore, the peripheral serotonergic system probably contributes to thrombocytopenia and capillary extravasation. CONCLUSION Regarding dengue, 5-HT may be a key parameter for predicting severity, and an understanding of 5-HT-related mechanisms could possibly facilitate the development of new therapies. These proposals require further research due to the limited number of publications on the role of serotonergic receptors at the peripheral level.
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Affiliation(s)
- Josselin Corzo-Gómez
- Pharmacology Laboratory, Faculty of Human Medicine, Autonomous University of Chiapas, Tuxtla Gutiérrez, Chiapas, México
| | - Ofir Picazo
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, México City, México
| | - Manuela Castellanos-Pérez
- Pharmacology Laboratory, Faculty of Human Medicine, Autonomous University of Chiapas, Tuxtla Gutiérrez, Chiapas, México
| | - Alfredo Briones-Aranda
- Pharmacology Laboratory, Faculty of Human Medicine, Autonomous University of Chiapas, Tuxtla Gutiérrez, Chiapas, México
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3
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Meng X, Grandjean J, Sbrini G, Schipper P, Hofwijks N, Stoop J, Calabrese F, Homberg J. Tryptophan Hydroxylase 2 Knockout Male Rats Exhibit a Strengthened Oxytocin System, Are Aggressive, and Are Less Anxious. ACS Chem Neurosci 2022; 13:2974-2981. [PMID: 36197033 PMCID: PMC9585586 DOI: 10.1021/acschemneuro.2c00448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 09/23/2022] [Indexed: 01/20/2023] Open
Abstract
The central serotoninergic system is critical for stress responsivity and social behavior, and its dysregulations have been centrally implicated in virtually all neuropsychiatric disorders. Genetic serotonin depletion animal models could provide a tool to elucidate the causes and mechanisms of diseases and to develop new treatment approaches. Previously, mice lacking tryptophan hydroxylase 2 (Tph2) have been developed, showing altered behaviors and neurotransmission. However, the effect of congenital serotonin deficiency on emotional and social behavior in rats is still largely unknown, as are the underlying mechanisms. In this study, we used a Tph2 knockout (Tph2-/-) male rat model to study how the lack of serotonin in the rat brain affects anxiety-like and social behaviors. Since oxytocin is centrally implicated in these behaviors, we furthermore explored whether the effects of Tph2 knockout on behavior would relate to changes in the oxytocin system. We show that Tph2-/- rats display reduced anxiety-like behavior and a high level of aggression in social interactions. In addition, oxytocin receptor expression was increased in the infralimbic and prelimbic cortices, paraventricular nucleus, dorsal raphe nucleus, and some subregions of the hippocampus, which was paralleled by increased levels of oxytocin in the medial frontal cortex and paraventricular nucleus but not the dorsal raphe nucleus, central amygdala, and hippocampus. In conclusion, our study demonstrated reduced anxiety but exaggerated aggression in Tph2-/- male rats and reveals for the first time a potential involvement of altered oxytocin system function. Meanwhile, the research of oxytocin could be distinguished in almost any psychiatric disorder including anxiety and mental disorders. This research potentially proposes a new target for the treatment of such disorders, from a genetic serotonin deficiency aspect.
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Affiliation(s)
- Xianzong Meng
- Department
of Cognitive Neuroscience, Donders Institute for Brain, Cognition,
and Behaviour, Radboud University Medical
Centre, 6525 AJ Nijmegen, The Netherlands
| | - Joanes Grandjean
- Department
of Cognitive Neuroscience, Donders Institute for Brain, Cognition,
and Behaviour, Radboud University Medical
Centre, 6525 AJ Nijmegen, The Netherlands
- Department
of Medical Imaging, Radboud University Medical
Centre, 6525 GA Nijmegen, The Netherlands
| | - Giulia Sbrini
- Department
of Pharmacological and Biomolecular Sciences, Università Degli Studi Di Milano, Via Balzaretti 9, 20133 Milan, Italy
| | - Pieter Schipper
- Department
of Cognitive Neuroscience, Donders Institute for Brain, Cognition,
and Behaviour, Radboud University Medical
Centre, 6525 AJ Nijmegen, The Netherlands
| | - Nita Hofwijks
- Department
of Cognitive Neuroscience, Donders Institute for Brain, Cognition,
and Behaviour, Radboud University Medical
Centre, 6525 AJ Nijmegen, The Netherlands
| | - Jesse Stoop
- Department
of Cognitive Neuroscience, Donders Institute for Brain, Cognition,
and Behaviour, Radboud University Medical
Centre, 6525 AJ Nijmegen, The Netherlands
| | - Francesca Calabrese
- Department
of Pharmacological and Biomolecular Sciences, Università Degli Studi Di Milano, Via Balzaretti 9, 20133 Milan, Italy
| | - Judith Homberg
- Department
of Cognitive Neuroscience, Donders Institute for Brain, Cognition,
and Behaviour, Radboud University Medical
Centre, 6525 AJ Nijmegen, The Netherlands
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Metabolic engineering of Corynebacterium glutamicum for de novo production of 3-hydroxycadaverine. CURRENT RESEARCH IN BIOTECHNOLOGY 2022. [DOI: 10.1016/j.crbiot.2021.12.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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5
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Disruption of tph1 genes demonstrates the importance of serotonin in regulating ventilation in larval zebrafish (Danio rerio). Respir Physiol Neurobiol 2020; 285:103594. [PMID: 33271304 DOI: 10.1016/j.resp.2020.103594] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 11/13/2020] [Accepted: 11/23/2020] [Indexed: 01/22/2023]
Abstract
Serotonergic neuroepithelial cells (NECs) in larval zebrafish are believed to be O2 chemoreceptors. Serotonin (5-HT) within these NECs has been implicated as a neurotransmitter mediating the hypoxic ventilatory response (HVR). Here, we use knockout approaches to discern the role of 5-HT in regulating the HVR by targeting the rate limiting enzyme for 5-HT synthesis, tryptophan hydroxylase (Tph). Using transgenic lines, we determined that Tph1a is expressed in skin and pharyngeal arch NECs, as well as in pharyngeal arch Merkel-like cells (MLCs), whereas Tph1b is expressed predominately in MLCs. Knocking out the two tph1 paralogs resulted in similar changes in detectable serotonergic cell density between the two mutants, yet their responses to hypoxia (35 mmHg) were different. Larvae lacking Tph1a (tph1a-/- mutants) displayed a higher ventilation rate when exposed to hypoxia compared to wild-types, whereas tph1b-/- mutants exhibited a lower ventilation rate suggesting that 5-HT located in locations other than NECs, may play a dominant role in regulating the HVR.
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Del Colle A, Israelyan N, Gross Margolis K. Novel aspects of enteric serotonergic signaling in health and brain-gut disease. Am J Physiol Gastrointest Liver Physiol 2020; 318:G130-G143. [PMID: 31682158 PMCID: PMC6985840 DOI: 10.1152/ajpgi.00173.2019] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 10/17/2019] [Accepted: 10/17/2019] [Indexed: 02/08/2023]
Abstract
Gastrointestinal (GI) comorbidities are common in individuals with mood and behavioral dysfunction. Similarly, patients with GI problems more commonly suffer from co-morbid psychiatric diagnoses. Although the central and enteric nervous systems (CNS and ENS, respectively) have largely been studied separately, there is emerging interest in factors that may contribute to disease states involving both systems. There is strong evidence to suggest that serotonin may be an important contributor to these brain-gut conditions. Serotonin has long been recognized for its critical functions in CNS development and function. The majority of the body's serotonin, however, is produced in the GI tract, where it plays key roles in ENS development and function. Further understanding of the specific impact that enteric serotonin has on brain-gut disease may lay the foundation for the creation of novel therapeutic targets. This review summarizes the current data focusing on the important roles that serotonin plays in ENS development and motility, with a focus on novel aspects of serotonergic signaling in medical conditions in which CNS and ENS co-morbidities are common, including autism spectrum disorders and depression.
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Affiliation(s)
- Andrew Del Colle
- Morgan Stanley Children's Hospital, Department of Pediatrics, Columbia University Medical Center, New York, New York
| | - Narek Israelyan
- Morgan Stanley Children's Hospital, Department of Pediatrics, Columbia University Medical Center, New York, New York
- Vagelos College of Physicians and Surgeons, Columbia University Medical Center, New York, New York
| | - Kara Gross Margolis
- Morgan Stanley Children's Hospital, Department of Pediatrics, Columbia University Medical Center, New York, New York
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Tan VX, Guillemin GJ. Kynurenine Pathway Metabolites as Biomarkers for Amyotrophic Lateral Sclerosis. Front Neurosci 2019; 13:1013. [PMID: 31616242 PMCID: PMC6764462 DOI: 10.3389/fnins.2019.01013] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 09/06/2019] [Indexed: 12/19/2022] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) currently lacks a robust and well-defined biomarker that can 1) assess the progression of the disease, 2) predict and/or delineate the various clinical subtypes, and 3) evaluate or predict a patient's response to treatments. The kynurenine Pathway (KP) of tryptophan degradation represent a promising candidate as it is involved with several neuropathological features present in ALS including neuroinflammation, excitotoxicity, oxidative stress, immune system activation and dysregulation of energy metabolism. Some of the KP metabolites (KPMs) can cross the blood brain barrier, and many studies have shown their levels are dysregulated in major neurodegenerative diseases including ALS. The KPMs can be easily analyzed in body fluids and tissue and as they are small molecules, and are stable. KPMs have a Janus face action, they can be either or both neurotoxic and/or neuroprotective depending of their levels. This mini review examines and presents evidence supporting the use of KPMs as a relevant set of biomarkers for ALS, and highlights the criteria required to achieve a valid biomarker set for ALS.
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Affiliation(s)
| | - Gilles J. Guillemin
- Macquarie University Centre for MND Research, Department of Biological Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
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Kulikova EA, Kulikov AV. Tryptophan hydroxylase 2 as a therapeutic target for psychiatric disorders: focus on animal models. Expert Opin Ther Targets 2019; 23:655-667. [PMID: 31216212 DOI: 10.1080/14728222.2019.1634691] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Introduction: Tryptophan hydroxylase 2 (TPH2) is the key, rate-limiting enzyme of serotonin (5-HT) synthesis in the brain. Some polymorphic variants of the human Tph2 gene are associated with psychiatric disorders. Area covered: This review focuses on the mechanisms underlying the association between the TPH2 activity and behavioral disturbances in models of psychiatric disorders. Specifically, it discusses: 1) genetic and posttranslational mechanisms defining the TPH2 activity, 2) behavioral effects of knockout and loss-of-function mutations in the mouse Tph2 gene, 3) pharmacological inhibition and the activation of the TPH2 activity and 4) alterations in the brain TPH2 activity in animal models of psychiatric disorders. We show the dual role of the TPH2 activity: both deficit and excess of the TPH2 activity cause significant behavioral disturbances in animal models of depression, anxiety, aggression, obsessive-compulsive disorders, schizophrenia, and catalepsy. Expert opinion: Pharmacological chaperones correcting the structure of the TPH2 molecule are promising tools for treatment of some hereditary psychiatric disorders caused by loss-of-function mutations in the human Tph2 gene; while some stress-induced affective disorders, associated with the elevated TPH2 activity, may be effectively treated by TPH2 inhibitors. This dual role of TPH2 should be taken into consideration during therapy of psychiatric disorders.
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Affiliation(s)
- Elizabeth A Kulikova
- a Federal Research Center Institute of Cytology and Genetics , Siberian Division of the Russian Academy of Science , Novosibirsk , Russia
| | - Alexander V Kulikov
- a Federal Research Center Institute of Cytology and Genetics , Siberian Division of the Russian Academy of Science , Novosibirsk , Russia
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Martínez-Idárraga A, Riveros-Barrera I, Sánchez R, Jaramillo LE, Calvo-Gómez JM, Yunis-Londoño JJ. [Characterisation of three polymorphisms of the tryptophan hydroxylase 2 gene in a sample of Colombian population with major depressive disorder]. REVISTA COLOMBIANA DE PSIQUIATRIA 2017; 46:22-30. [PMID: 28193370 DOI: 10.1016/j.rcp.2016.03.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 02/15/2016] [Accepted: 03/25/2016] [Indexed: 06/06/2023]
Abstract
OBJECTIVE Identify whether rs11179000, rs136494 and rs4570625 polymorphisms of the tryptophan hydroxylase 2 gene, are associated with a major depressive disorder in a sample of the Colombian population. METHODS Case-control study was conducted in which a comparison was made between subjects diagnosed with major depressive disorder at some point in adulthood or active symptoms at the time of evaluation, and subjects with no psychiatric disease. Subjects were studied in the Department of Psychiatry, Faculty of Medicine and the Institute of Genetics at the National University of Colombia. Polymorphisms were genotyped using Taqman probes in real time PCR. As well as studying the association between major depressive disorder and these (single nucleotide polymorphisms (SNPs), the association with other factors previously associated with depression were also analysed. RESULTS No statistically significant association between genotypic and allelic frequencies of each polymorphism and major depressive disorder was found. Association between sex and complication during pregnancy / childbirth and major depressive disorder was observed. Association between sex and complication during pregnancy / childbirth and major depressive disorder was observed. CONCLUSIONS There was no association between any polymorphism and major depressive disorder.
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Affiliation(s)
- Adriana Martínez-Idárraga
- Departamento de Psiquiatría, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Irene Riveros-Barrera
- Grupo de Patología Molecular, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia; Instituto de Genética, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Ricardo Sánchez
- Departamento de Psiquiatría, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Luis Eduardo Jaramillo
- Departamento de Psiquiatría, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia
| | - José Manuel Calvo-Gómez
- Departamento de Psiquiatría, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia.
| | - Juan José Yunis-Londoño
- Grupo de Patología Molecular, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia; Instituto de Genética, Universidad Nacional de Colombia, Bogotá, Colombia
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Jakubczyk A, Krasowska A, Bugaj M, Kopera M, Klimkiewicz A, Łoczewska A, Michalska A, Majewska A, Szejko N, Podgórska A, Sołowiej M, Markuszewski L, Jakima S, Płoski R, Brower K, Wojnar M. Paraphilic Sexual Offenders Do Not Differ From Control Subjects With Respect to Dopamine- and Serotonin-Related Genetic Polymorphisms. J Sex Med 2016; 14:125-133. [PMID: 27989490 DOI: 10.1016/j.jsxm.2016.11.309] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 11/11/2016] [Accepted: 11/16/2016] [Indexed: 02/05/2023]
Abstract
INTRODUCTION Rape and pedophilic child molestation are the most commonly convicted sexual offenses in Poland. Recent studies have suggested a possible genetic contribution toward pathologic sexual interests and behaviors. AIM To analyze and compare functional polymorphisms of genes associated with the activity of the serotonin and dopamine systems in a group of paraphilic sexual offenders and control subjects. METHODS The study sample (n = 97) consisted of two groups: paraphilic sexual offenders (65 pedophilic child molesters and 32 rapists) and controls (n = 76). Genetic polymorphisms previously associated with behavioral control, addictive behaviors, and sexual functions were chosen for analyses. Specifically, functional polymorphisms in dopamine receptors genes (DRD1, DRD2, DRD4), catechol-O-methyltransferase gene (COMT), dopamine transporter gene (DAT), serotonin transporter gene (SLC6A4), serotonin type 2A receptor gene (5HTR2A), tryptophan hydroxylase 2 gene (TPH2), monoamine oxidase A gene (MAOA), and brain-derived neurotrophic factor gene (BDNF) were analyzed. MAIN OUTCOME MEASURES An association between a history of sexual offense and the distribution of genotypes and alleles in the analyzed polymorphisms. RESULTS Our results found no association between a history of sexual offense and the distribution of genotypes or alleles in the analyzed polymorphisms. CONCLUSION Although these results are limited by the small sample and are exploratory, they highlight a novel approach to sample selection in a population that is difficult to access and study. Future research should include larger samples and other relevant polymorphisms to advance this field of study.
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Affiliation(s)
- Andrzej Jakubczyk
- Department of Psychiatry, Medical University of Warsaw, Warsaw, Poland
| | | | - Marcin Bugaj
- Department of Psychiatry, Medical University of Warsaw, Warsaw, Poland
| | - Maciej Kopera
- Department of Psychiatry, Medical University of Warsaw, Warsaw, Poland
| | - Anna Klimkiewicz
- Department of Psychiatry, Medical University of Warsaw, Warsaw, Poland
| | - Agata Łoczewska
- Department of Psychiatry, Medical University of Warsaw, Warsaw, Poland
| | - Aneta Michalska
- Department of Psychiatry, Medical University of Warsaw, Warsaw, Poland
| | | | - Natalia Szejko
- Department of Neurology, Wolski Hospital, Warsaw, Poland; Department of Neurology, Faculty of Health Science, Medical University of Warsaw, Warsaw, Poland
| | - Anna Podgórska
- Department of Genetics, Institute of Physiology and Pathology of Hearing, Warsaw, Poland
| | | | - Leszek Markuszewski
- Department of Endocrinology and Metabolic Diseases, Polish Mother's Memorial Hospital Research Institute, Lodz, Poland
| | - Sławomir Jakima
- Department of Sexology, Center of Psychotherapy Nowowiejski Hospital, Warsaw, Poland
| | - Rafał Płoski
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
| | - Kirk Brower
- Department of Endocrinology and Metabolic Diseases, Polish Mother's Memorial Hospital Research Institute, Lodz, Poland
| | - Marcin Wojnar
- Department of Psychiatry, Medical University of Warsaw, Warsaw, Poland; Department of Psychiatry, University of Michigan, Ann Arbor, MI, USA
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Plemenitaš A, Kores Plesničar B, Kastelic M, Porcelli S, Serretti A, Dolžan V. Genetic variability in tryptophan hydroxylase 2 gene in alcohol dependence and alcohol-related psychopathological symptoms. Neurosci Lett 2015; 604:86-90. [PMID: 26232682 DOI: 10.1016/j.neulet.2015.07.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 07/23/2015] [Accepted: 07/27/2015] [Indexed: 12/24/2022]
Abstract
Heritability plays an important role in the development and expression of alcohol dependence. The present genetic association study explored the role of TPH2 polymorphisms and their haplotypes to investigate its role in alcohol dependence and comorbid psychopathological symptoms. The sample included 101 subjects currently diagnosed as alcohol abusers, 100 abstinent alcohol-dependent subjects and 97 healthy controls. Subjects were genotyped for TPH2 rs4570625, rs1843809, rs7305115, rs4290270. TPH2 genotypes were not associated with alcohol dependence, but GGAA haplotype was less common (p=0.038) and GTAA and GGGT were more common (p=0.011 and p=0.021, respectively), in currently dependent patients compared to controls. Exploratory analysis of genotypes in currently dependent patients showed that rs1843809 was associated with depressive and aggressive traits (p=0.045 and p=0.001, respectively), rs4290270 with depressive and anxiety traits (p=0.040 and p=0.025, respectively) and rs4570625 with aggressive traits (p=0.011). In abstinent subjects rs1843809 genotype was associated with traits of social anxiety (p=0.003). Only association between rs1843809 and the BDHI score (p=0.001) and associations between GTAA haplotype and Zung Anxiety Scale and BDHI score (p=0.001 and p<0.001, respectively), in currently dependent patients remained significant after applying the Bonferroni's correction. Our findings support a potential role of TPH2 in alcohol dependence. TPH2 genetic variability may be also associated with anxiety and aggression traits in alcohol dependent subjects.
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Affiliation(s)
- Anja Plemenitaš
- Department of Psychiatry, University Clinical Center Maribor, Maribor, Slovenia
| | | | - Matej Kastelic
- Pharmacogenetics Laboratory, Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Stefano Porcelli
- Department of Biomedical and NeuroMotor Sciences, University of Bologna, Bologna, Italy
| | - Alessandro Serretti
- Department of Biomedical and NeuroMotor Sciences, University of Bologna, Bologna, Italy
| | - Vita Dolžan
- Pharmacogenetics Laboratory, Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.
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Effects of estrogen on the serotonergic system and calcitonin gene-related peptide in trigeminal ganglia of rats. Ann Neurosci 2014; 19:151-7. [PMID: 25205989 PMCID: PMC4117063 DOI: 10.5214/ans.0972.7531.190403] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 07/03/2012] [Accepted: 09/21/2012] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND The prevalence of migraine is 3-folds higher in females than in males, and it is intricately related to the levels of estrogen. Estrogen may regulate the expression of metabolic enzymes and receptors of serotonin and also calcitonin gene-related peptide (CGRP), which are implicated in migraine pathogenesis. PURPOSE To study the effects of estrogen on the components of serotonin system and CGRP in trigeminal ganglia of ovariectomized (OVX) rats. METHODS OVX rats were administered estrogen in silastic tubes and after 48 h, serum estrogen levels were determined. Trigeminal ganglia tissues were used for RT-PCRs of tryptophan hydroxylase (TPH), monoamine oxidase (MAO), serotonin receptors (5-HT1A, 5-HT1B, 5-HT2A), estrogen receptor (ER) and CGRP. Western blots of TPH and MAO were performed. RESULTS Estradiol administration to OVX rats increased TPH mRNA levels, while decreased MAO mRNA levels in trigeminal ganglia tissue. Western blot data correlate with the gene expression results. The decreased mRNA levels of serotonin receptors following ovariectomy were restored in estrogen-replenished rats. The induced gene expression of ER in OVX rats was restored following estrogen replenishment. CONCLUSION Estrogen levels affect the levels of serotonin metabolizing enzymes and its receptors besides CGRP levels. Since TPH and MAO levels regulate circulating and physiologically available serotonin content, the regulation of serotonin metabolizing enzymes suggest a plausible mechanism by which estrogen alleviates migraine in women.
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Carkaci-Salli N, Salli U, Tekin I, Hengst JA, Zhao MK, Gilman TL, Andrews AM, Vrana KE. Functional characterization of the S41Y (C2755A) polymorphism of tryptophan hydroxylase 2. J Neurochem 2014; 130:748-58. [PMID: 24899127 DOI: 10.1111/jnc.12779] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 05/23/2014] [Indexed: 01/11/2023]
Abstract
Human TPH2 (hTPH2) catalyzes the rate-limiting step in CNS serotonin biosynthesis. We characterized a single-nucleotide polymorphism (C2755A) in the hTPH2 gene that substitutes tyrosine for serine at position 41 in the regulatory domain of the enzyme. This polymorphism is associated with bipolar disorder and peripartum depression in a Chinese population. Recombinant h TPH2 human proteins were expressed in bacteria and also stably expressed in PC12 cells. Following bacterial expression and purification, the tyrosine for serine substitution at position 41 (S41Y) polymorphic enzyme displayed increased Vmax with unchanged Km values. By contrast, enzyme stability was decreased in vitro from 32 min to 4 min (37 °C) for the S41Y enzyme (as compared to the wild-type enzyme). The S41Y polymorphism decreased cyclic AMP-dependent protein kinase A-mediated phosphorylation ~ 50% relative to wild-type hTPH2, suggesting that the S41Y mutation may disrupt the post-translational regulation of this enzyme. Transfected PC12 cells expressed hTPH2 mRNA, active protein, and synthesized and released serotonin. Paradoxically, while S41Y-transfected PC12 cells expressed higher levels of hTPH2 than wild type, they synthesized less serotonin. These findings suggest a modified regulation of the S41Y gene variant leading to altered regulation and reduced neurotransmitter synthesis that may contribute to association of the polymorphism with bipolar disorder and depression. We report the functional implications of a polymorphic human tryptophan hydroxylase-2 gene associated with depression and bipolar disorder. The polymorphic enzyme (serine-41 converted to tyrosine) has increased activity, but decreased enzyme stability and serotonin production. Moreover, cyclic AMP-dependent protein kinase (PKA)-mediated phosphorylation of the mutant enzyme is decreased suggesting modified regulation of the S41Y variant leading to altered serotonin.
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Affiliation(s)
- Nurgul Carkaci-Salli
- Department of Pharmacology, Penn State College of Medicine, Hershey, Pennsylvania, USA
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14
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Zheng P, Li E, Wang J, Cui X, Wang L. Involvement of tryptophan hydroxylase 2 gene polymorphisms in susceptibility to tic disorder in Chinese Han population. Behav Brain Funct 2013; 9:6. [PMID: 23360517 PMCID: PMC3573945 DOI: 10.1186/1744-9081-9-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 01/22/2013] [Indexed: 01/27/2023] Open
Abstract
Background Tryptophan hydroxylase-2 (TPH2) is a potential candidate gene for screening tic disorder (TD). Methods A case–control study was performed to examine the association between the TPH2 gene and TD. The Sequenom® Mass ARRAY iPLEX GOLD System was used to genotype two single nucleotide polymorphisms (SNPs) of the TPH2 gene in 149 TD children and in 125 normal controls. Results For rs4565946, individuals with the TT genotype showed a significantly higher risk of TD than those with TC plus CC genotypes [odds ratio (OR) =3.077, 95% confidence interval (CI): 1.273–7.437; P = 0.009], as did male TD children with the TT genotype (OR = 3.228, 95% CI: 1.153–9.040; P = 0.020). The G allele of rs4570625 was significantly more frequent in TD children with higher levels of tic symptoms (Yale Global Tic Severity Scale, YGTSS) than those in controls among the male children (OR = 1.684, 95%: 1.097–2.583; P = 0.017]. TD children with severe tic symptoms had significantly higher frequencies of rs4546946 TT genotype than did normal controls in boys (OR = 3.292, 95% CI: 1.139–9.513; P = 0.022). We also found that genotype distributions of both SNPs were different between the Asian and European populations. Conclusions Our results indicated that the TT genotype of rs4565946 is a potential genetic risk factor for TD, and the allele G of rs4570625 might be associated with the severity of tic symptoms in boys. These polymorphisms might be susceptibility loci for TD in the Chinese Han population. Because of the confounding of co-existing attention deficit hyperactivity disorder (ADHD),these findings need to be confirmed by studies in much larger samples.
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Affiliation(s)
- Ping Zheng
- Department of Neurological medicine, Capital Institute of Pediatrics, Beijing, 100020, China
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15
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The role of the serotonergic system at the interface of aggression and suicide. Neuroscience 2013; 236:160-85. [PMID: 23333677 DOI: 10.1016/j.neuroscience.2013.01.015] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 01/01/2013] [Accepted: 01/05/2013] [Indexed: 02/07/2023]
Abstract
Alterations in serotonin (5-HT) neurochemistry have been implicated in the aetiology of all major neuropsychiatric disorders, ranging from schizophrenia to mood and anxiety-spectrum disorders. This review will focus on the multifaceted implications of 5-HT-ergic dysfunctions in the pathophysiology of aggressive and suicidal behaviours. After a brief overview of the anatomical distribution of the 5-HT-ergic system in the key brain areas that govern aggression and suicidal behaviours, the implication of 5-HT markers (5-HT receptors, transporter as well as synthetic and metabolic enzymes) in these conditions is discussed. In this regard, particular emphasis is placed on the integration of pharmacological and genetic evidence from animal studies with the findings of human experimental and genetic association studies. Traditional views postulated an inverse relationship between 5-HT and aggression and suicidal behaviours; however, ample evidence has shown that this perspective may be overly simplistic, and that such pathological manifestations may reflect alterations in 5-HT homoeostasis due to the interaction of genetic, environmental and gender-related factors, particularly during early critical developmental stages. The development of animal models that may capture the complexity of such interactions promises to afford a powerful tool to elucidate the pathophysiology of impulsive aggression and suicidability, and identify new effective therapies for these conditions.
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16
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Siesser WB, Sachs BD, Ramsey AJ, Sotnikova TD, Beaulieu JM, Zhang X, Caron MG, Gainetdinov RR. Chronic SSRI treatment exacerbates serotonin deficiency in humanized Tph2 mutant mice. ACS Chem Neurosci 2013; 4:84-8. [PMID: 23336047 DOI: 10.1021/cn300127h] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 10/01/2012] [Indexed: 01/12/2023] Open
Abstract
Selective serotonin reuptake inhibitors (SSRIs) are a major class of antidepressants that act by blocking inward transport of serotonin (5-HT) into presynaptic neurons mediated by the serotonin transporter (SERT). Both reuptake and ongoing synthesis are essential in supporting intraneuronal serotonin concentrations in serotonergic neurons. A rare mutation in tryptophan hydroxylase 2 (Tph2), the rate limiting enzyme for 5-HT synthesis, was identified in several patients with major depression, and knock-in mice expressing the analogous mutation (R439H Tph2 KI) show 80% reduction in 5-HT synthesis and tissue levels. Chronic treatment with SSRIs (fluoxetine and paroxetine) resulted in a dramatic further depletion of 5-HT tissue levels in R439H Tph2 KI mice (down to 1-3% of wild type levels) while having little effects in wild-type controls. Treatment with the 5-HT precursor 5-hydroxytryptophan (5-HTP) restored 5-HT tissue content in mutant mice, and cotreatment with 5-HTP and fluoxetine essentially prevented the depleting effect of a chronic SSRI. These data demonstrate that chronic SSRI treatment could further exacerbate the 5-HT deficiency in Tph2 mutation carriers, and this can be prevented by 5-HTP supplementation.
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Affiliation(s)
- William B. Siesser
- Department of Cell Biology, Duke University, Durham, North Carolina 27710, United
States
| | - Benjamin D. Sachs
- Department of Cell Biology, Duke University, Durham, North Carolina 27710, United
States
| | - Amy J. Ramsey
- Department of Pharmacology
and
Toxicology, University of Toronto, ON,
Canada M5S 1A8
| | - Tatyana D. Sotnikova
- Department
of Neuroscience and
Brain Technologies, Istituto Italiano di Tecnologia (IIT), Via Morego 30, Genova, 16163 Italy
| | - Jean-Martin Beaulieu
- Department of Psychiatry and
Neuroscience, Université Laval/IUSMQ, Québec, Canada
| | - Xiaodong Zhang
- Neuroscience & Behavioral Disorders Program, Duke−NUS Graduate Medical School Singapore, Singapore
- Department of Physiology, National University of Singapore, Singapore
- Department
of Psychiatry and
Behavioral Sciences, Duke University Medical Center, Durham, North Carolina 27710, United States
| | - Marc G. Caron
- Department of Cell Biology, Duke University, Durham, North Carolina 27710, United
States
- Department of Neurobiology, Duke University Medical Center, Durham, North Carolina
27710, United States
| | - Raul R. Gainetdinov
- Department of Cell Biology, Duke University, Durham, North Carolina 27710, United
States
- Department
of Neuroscience and
Brain Technologies, Istituto Italiano di Tecnologia (IIT), Via Morego 30, Genova, 16163 Italy
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17
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Lin CH, Tseng YL, Huang CL, Chang YC, Tsai GE, Lane HY. Synergistic effects of COMT and TPH2 on social cognition. Psychiatry 2013; 76:273-94. [PMID: 23965265 DOI: 10.1521/psyc.2013.76.3.273] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Whether genetic factors affect social cognition, particularly emotion management, requires elucidation. This study investigates whether social cognition varies with genetic variations of COMT and tryptophan hydroxylase-2 (TPH2), which modulate dopamine and serotonin neurotransmissions respectively, and thereby emotion regulation. NIMH-recommended "managing emotions branch and 2 subtasks" of MSCEIT and six neurocognition domains, and genotypes of COMT Val158Met and TPH2 G703T were measured in 150 Han-Chinese healthy adults. Subjects carrying the M allele (M group) of COMT exceeded Val/Val homozygotes (V group) in managing emotions branch (p = 0.032) and emotional relation subtask (p = 0.037). TPH2 T/T homozygotes (T group) excelled those with the G allele (G group) in emotional management subtask (p = 0.025). Subjects with M+T variation surpassed the other 3 groups (M+G, V+T and V+G) in managing emotion branch (p = 0.002), emotional relation subtask (p = 0.023), and emotional management subtask (p = 0.002). The findings remained after control for gender, age, education, and neurocognitive functions. Synergistically, the effect size of COMT-TPH2 combination surmounted the sum of separate effect sizes of COMT and TPH2. The findings suggest that genetic variations of COMT and TPH2 have synergistic effects on social cognition in the general population.
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Affiliation(s)
- Chieh-Hsin Lin
- Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan
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18
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Kane MJ, Angoa-Peréz M, Briggs DI, Sykes CE, Francescutti DM, Rosenberg DR, Kuhn DM. Mice genetically depleted of brain serotonin display social impairments, communication deficits and repetitive behaviors: possible relevance to autism. PLoS One 2012; 7:e48975. [PMID: 23139830 PMCID: PMC3490915 DOI: 10.1371/journal.pone.0048975] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Accepted: 10/01/2012] [Indexed: 01/10/2023] Open
Abstract
Autism is a complex neurodevelopmental disorder characterized by impaired reciprocal social interaction, communication deficits and repetitive behaviors. A very large number of genes have been linked to autism, many of which encode proteins involved in the development and function of synaptic circuitry. However, the manner in which these mutated genes might participate, either individually or together, to cause autism is not understood. One factor known to exert extremely broad influence on brain development and network formation, and which has been linked to autism, is the neurotransmitter serotonin. Unfortunately, very little is known about how alterations in serotonin neuronal function might contribute to autism. To test the hypothesis that serotonin dysfunction can contribute to the core symptoms of autism, we analyzed mice lacking brain serotonin (via a null mutation in the gene for tryptophan hydroxylase 2 (TPH2)) for behaviors that are relevant to this disorder. Mice lacking brain serotonin (TPH2-/-) showed substantial deficits in numerous validated tests of social interaction and communication. These mice also display highly repetitive and compulsive behaviors. Newborn TPH2-/- mutant mice show delays in the expression of key developmental milestones and their diminished preference for maternal scents over the scent of an unrelated female is a forerunner of more severe socialization deficits that emerge in weanlings and persist into adulthood. Taken together, these results indicate that a hypo-serotonin condition can lead to behavioral traits that are highly characteristic of autism. Our findings should stimulate new studies that focus on determining how brain hyposerotonemia during critical neurodevelopmental periods can alter the maturation of synaptic circuits known to be mis-wired in autism and how prevention of such deficits might prevent this disorder.
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Affiliation(s)
- Michael J. Kane
- Research and Development Service, John D. Dingell VA Medical Center, Detroit, Michigan, United States of America
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - Mariana Angoa-Peréz
- Research and Development Service, John D. Dingell VA Medical Center, Detroit, Michigan, United States of America
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - Denise I. Briggs
- Research and Development Service, John D. Dingell VA Medical Center, Detroit, Michigan, United States of America
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - Catherine E. Sykes
- Research and Development Service, John D. Dingell VA Medical Center, Detroit, Michigan, United States of America
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - Dina M. Francescutti
- Research and Development Service, John D. Dingell VA Medical Center, Detroit, Michigan, United States of America
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - David R. Rosenberg
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - Donald M. Kuhn
- Research and Development Service, John D. Dingell VA Medical Center, Detroit, Michigan, United States of America
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, United States of America
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19
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Rietjens SJ, Hondebrink L, Westerink RHS, Meulenbelt J. Pharmacokinetics and pharmacodynamics of 3,4-methylenedioxymethamphetamine (MDMA): interindividual differences due to polymorphisms and drug-drug interactions. Crit Rev Toxicol 2012; 42:854-76. [PMID: 23030234 DOI: 10.3109/10408444.2012.725029] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Clinical outcome following 3,4-methylenedioxymethamphetamine (MDMA) intake ranges from mild entactogenic effects to a life-threatening intoxication. Despite ongoing research, the clinically most relevant mechanisms causing acute MDMA-induced adverse effects remain largely unclear. This complicates the triage and treatment of MDMA users needing medical care. The user's genetic profile and interactions resulting from polydrug use are key factors that modulate the individual response to MDMA and influence MDMA pharmacokinetics and dynamics, and thus clinical outcome. Polymorphisms in CYP2D6, resulting in poor metabolism status, as well as co-exposure of MDMA with specific substances (e.g. selective serotonin reuptake inhibitors (SSRIs)) can increase MDMA plasma levels, but can also decrease the formation of toxic metabolites and subsequent cellular damage. While pre-exposure to e.g. SSRIs can increase MDMA plasma levels, clinical effects (e.g. blood pressure, heart rate, body temperature) can be reduced, possibly due to a pharmacodynamic interaction at the serotonin reuptake transporter (SERT). Pretreatment with inhibitors of the dopamine or norepinephrine reuptake transporter (DAT or NET), 5-HT(2A) or α-β adrenergic receptor antagonists or antipsychotics prior to MDMA exposure can also decrease one or more MDMA-induced physiological and/or subjective effects. Carvedilol, ketanserin and haloperidol can reduce multiple MDMA-induced clinical and neurotoxic effects. Thus besides supportive care, i.e. sedation using benzodiazepines, intravenous hydration, aggressive cooling and correction of electrolytes, it is worthwhile to investigate the usefulness of carvedilol, ketanserin and haloperidol in the treatment of MDMA-intoxicated patients.
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Affiliation(s)
- Saskia J Rietjens
- University Medical Center Utrecht, Division of Anesthesiology, Intensive Care and Emergency Medicine, National Poisons Information Center (NVIC), P.O. box 85500, 3508 GA, Utrecht, The Netherlands.
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20
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Kennedy AP, Binder EB, Bowman D, Harenski K, Ely T, Cisler JM, Tripathi SP, VanNess S, Kilts CD. A common TPH2 haplotype regulates the neural processing of a cognitive control demand. Am J Med Genet B Neuropsychiatr Genet 2012; 159B:829-40. [PMID: 22915309 DOI: 10.1002/ajmg.b.32090] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Accepted: 07/11/2012] [Indexed: 11/10/2022]
Abstract
The monoamine neurotransmitter, serotonin, critically regulates the function of the cerebral cortex and is involved in psychiatric disorders. Tryptophan hydroxylase (TPH) is the rate-limiting enzyme in the synthesis of serotonin with the neuron-specific TPH2 isoform present exclusively in the brain and encoded by the TPH2 gene on chromosome 12q21. The haplotype structure of TPH2 was defined for 16 single-nucleotide polymorphisms (SNPs) in a healthy subject population and a haplotype block analysis confirmed the presence of a six SNP haplotype in a yin configuration that has previously been associated with risk for suicidality, depression, and anxiety disorders. Functional magnetic resonance imaging (fMRI) was used to assess the influence of TPH2 variation on brain function related to cognitive control using the Multi-Source Interference Task (MSIT). The MSIT-related blood oxygen level-dependent (BOLD) response was increased with increasing copies of the TPH2 yin haplotype for the dorsal anterior cingulate cortex (dACC), right inferior frontal cortex (IFC), and anterior striatum. A functional connectivity analysis further revealed that increasing numbers of the TPH2 yin haplotype was associated with diminished functional coupling between the dACC and the right IFC, precentral gyrus, parietal cortex and dlPFC. A moderation analysis indicated that the relationship between neural processing networks and cognitive control was significantly modulated by allelic variation for the TPH2 yin haplotype. These findings suggest that the association of risk for psychiatric disorders with a common TPH2 yin haplotype is related to the inefficient functional engagement of cortical areas involved in cognitive control and alterations in the mode of functional connectivity of dACC pathways.
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Affiliation(s)
- Ashley P Kennedy
- Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, Georgia, USA
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21
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Torrente MP, Gelenberg AJ, Vrana KE. Boosting serotonin in the brain: is it time to revamp the treatment of depression? J Psychopharmacol 2012; 26:629-35. [PMID: 22158544 PMCID: PMC3325323 DOI: 10.1177/0269881111430744] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Abnormalities in serotonin systems are presumably linked to various psychiatric disorders including schizophrenia and depression. Medications intended for these disorders aim to either block the reuptake or the degradation of this neurotransmitter. In an alternative approach, efforts have been made to enhance serotonin levels through dietary manipulation of precursor levels with modest clinical success. In the last 30 years, there has been little improvement in the pharmaceutical management of depression, and now is the time to revisit therapeutic strategies for the treatment of this disease. Tryptophan hydroxylase (TPH) catalyzes the first and rate-limiting step in the biosynthesis of serotonin. A recently discovered isoform, TPH2, is responsible for serotonin biosynthesis in the brain. Learning how to activate this enzyme (and its polymorphic versions) may lead to a new, more selective generation of antidepressants, able to regulate the levels of serotonin in the brain with fewer side effects.
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Affiliation(s)
- Mariana P Torrente
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA, USA
| | - Alan J Gelenberg
- Department of Psychiatry, Penn State College of Medicine, Hershey, PA, USA
| | - Kent E Vrana
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA, USA
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22
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Egawa J, Watanabe Y, Nunokawa A, Endo T, Kaneko N, Tamura R, Sugiyama T, Someya T. A detailed association analysis between the tryptophan hydroxylase 2 (TPH2) gene and autism spectrum disorders in a Japanese population. Psychiatry Res 2012; 196:320-2. [PMID: 22361444 DOI: 10.1016/j.psychres.2011.09.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Revised: 08/11/2011] [Accepted: 09/01/2011] [Indexed: 12/23/2022]
Abstract
We conducted a detailed association analysis between the tryptophan hydroxylase 2 gene and autism spectrum disorders in a Japanese population using 19 markers, including tagging single nucleotide polymorphisms and a novel missense variation, p.R225Q, identified through exon resequencing. However, we failed to obtain supportive evidence for an association.
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Affiliation(s)
- Jun Egawa
- Department of Psychiatry, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
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23
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Aggarwal M, Puri V, Puri S. Serotonin and CGRP in migraine. Ann Neurosci 2012; 19:88-94. [PMID: 25205974 PMCID: PMC4117050 DOI: 10.5214/ans.0972.7531.12190210] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2011] [Revised: 01/30/2012] [Accepted: 03/02/2012] [Indexed: 12/21/2022] Open
Abstract
Migraine is defined as recurrent attack of headache that are commonly unilateral and accompanied by gastrointestinal and visual disorders. Migraine is more prevalent in females than males with a ratio of 3:1. It is primarily a complex neurovascular disorder involving local vasodilation of intracranial, extracerebral blood vessels and simultaneous stimulation of surrounding trigeminal sensory nervous pain pathway that results in headache. The activation of 'trigeminovascular system' causes release of various vasodilators, especially calcitonin gene-related peptide (CGRP) that induces pain response. At the same time, decreased levels of neurotransmitter, serotonin have been observed in migraineurs. Serotonin receptors have been found on the trigeminal nerve and cranial vessels and their agonists especially triptans prove effective in migraine treatment. It has been found that triptans act on trigeminovascular system and bring the elevated serum levels of key molecules like calcitonin gene related peptide (CGRP) to normal. Currently CGRP receptor antagonists, olcegepant and telcagepant are under consideration for antimigraine therapeutics. It has been observed that varying levels of ovarian hormones especially estrogen influence serotonin neurotransmission system and CGRP levels making women more predisposed to migraine attacks. This review provides comprehensive information about the role of serotonin and CGRP in migraine, specifically the menstrual migraine.
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Affiliation(s)
- Milan Aggarwal
- Department of Biochemistry, Panjab University, Chandigarh 160014
| | - Veena Puri
- Centre for Systems biology & Bioinformatics, Panjab University, Chandigarh
| | - Sanjeev Puri
- Biotechnology Branch (U.I.E.T)
- Centre for Stem Cell & Tissue Engineering Panjab University, Chandigarh 160014, INDIA
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24
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Common variants in the TPH2 promoter confer susceptibility to paranoid schizophrenia. J Mol Neurosci 2012; 47:465-9. [PMID: 22392150 DOI: 10.1007/s12031-012-9725-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 02/10/2012] [Indexed: 12/31/2022]
Abstract
Serotonergic system-related genes may be good candidates in investigating the genetic basis of schizophrenia. Our previous study suggested that promoter region of tryptophan hydroxylase 2 gene (TPH2) may confer the susceptibility to paranoid schizophrenia. In this study, we investigated whether common variants within TPH2 promoter may predispose to paranoid schizophrenia in Han Chinese. A total of 509 patients who met DSM-IV criteria for paranoid schizophrenia and 510 matched healthy controls were recruited for this study. Five polymorphisms within TPH2 promoter region were tested. No statistically significant differences were found in allele or genotype frequencies between schizophrenic patients and healthy controls. The frequency of the rs4448731T-rs6582071A-rs7963803A-rs4570625T-rs11178997A haplotype was significantly higher in cases compared to the controls (P = 0.003; OR = 1.49; 95% CI, 1.15-1.95). Our results suggest that the common variants within TPH2 promoter are associated with paranoid schizophrenia in Han Chinese. Further studies in larger samples are warranted to elucidate the role of TPH2 in the etiology of paranoid schizophrenia.
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25
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Hempfling C, Neuhuber WL, Wörl J. Serotonin-immunoreactive neurons and mast cells in the mouse esophagus suggest involvement of serotonin in both motility control and neuroimmune interactions. Neurogastroenterol Motil 2012; 24:e67-78. [PMID: 22029710 DOI: 10.1111/j.1365-2982.2011.01797.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Serotonin is a major transmitter in the gastrointestinal tract, but little is known about the serotonergic system in the esophagus. METHODS The aim of this study was to use multilabel immunofluorescence to characterize serotonin-positive nerve cell bodies and fibers and their relationship with other neuronal and non-neuronal elements in the mouse esophagus. Antibodies against serotonin, vesicular acetylcholine transporter (VAChT), choline acetyltransferase (ChAT), protein gene product 9.5 (PGP 9.5), and α-bungarotoxin (α-BT), were used. KEY RESULTS Serotonin-containing perikarya represented ∼10% of all PGP 9.5-positive myenteric neurons. Serotonin-positive varicose nerve fibers were found in the lamina muscularis mucosae and present on ∼13% of α-BT-labeled motor endplates in addition to VAChT-immunoreactive motor terminals. As ChAT-positive neurons of the compact formation of the nucleus ambiguus were negative for serotonin, serotonin-positive varicosities on motor endplates are presumed to be of enteric origin. On the other hand, cholinergic ambiguus neurons were densely supplied with serotonin-positive varicosities. The tela submucosa and tunica adventitia contained large numbers of serotonin-positive mast cells, a few of which were in close association with serotonin-positive nerve fibers. CONCLUSIONS & INFERENCES The mouse esophagus is endowed with a rich serotonin-positive intrinsic innervation, including enteric co-innervation of striated muscles. Serotonin may modulate vagal motor innervation of esophageal-striated muscles not only at the central level via projections of the raphe nuclei to the nucleus ambiguus but also at the peripheral level via enteric co-innervation. In addition, mast cells represent a non-neuronal source of serotonin, being involved in neuroimmune processes.
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Affiliation(s)
- C Hempfling
- Institute of Anatomy, University of Erlangen-Nuremberg, Erlangen, Germany
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26
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Hart AB, de Wit H, Palmer AA. Genetic factors modulating the response to stimulant drugs in humans. Curr Top Behav Neurosci 2012; 12:537-77. [PMID: 22261702 PMCID: PMC3388157 DOI: 10.1007/7854_2011_187] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Individuals vary in their responses to stimulant drugs, and several lines of evidence suggest that the basis for this variation is at least partially genetic in origin. Association studies have examined the effects of polymorphisms in specific genes on acute and chronic responses to stimulant drugs. Several of these genetic polymorphisms are also associated with other psychiatric dimensions and disorders.This chapter examines the evidence for genetic associations between the genes that have been most carefully examined for their influence on the response to stimulant drugs.
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27
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Beaulieu JM. A role for Akt and glycogen synthase kinase-3 as integrators of dopamine and serotonin neurotransmission in mental health. J Psychiatry Neurosci 2012; 37:7-16. [PMID: 21711983 PMCID: PMC3244494 DOI: 10.1503/jpn.110011] [Citation(s) in RCA: 183] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Mental illnesses, such as bipolar disorder, attention-deficit/hyperactivity disorder, depression and schizophrenia are a major public health concern worldwide. Several pharmacologic agents acting on monoamine neurotransmission are used for the management of these disorders. However, there is still little understanding of the ultimate molecular mechanisms responsible for the therapeutic effects of these drugs or their relations with disease etiology. Here I provide an overview of recent advances on the involvement of the signalling molecules Akt and glycogen synthase kinase-3 (GSK3) in the regulation of behaviour by the monoamine neurotransmitters dopamine (DA) and serotonin (5-HT). I examine the possible participation of these signalling molecules to the effects of antidepressants, lithium and antipsychotics, as well as their possible contribution to mental disorders. Regulation of Akt and GSK3 may constitute an important signalling hub in the subcellular integration of 5-HT and DA neurotransmission. It may also provide a link between the action of these neurotransmitters and gene products, like disrupted in schizophrenia 1 (DISC1) and neuregulin (NRG), that are associated with increased risk for mental disorders. However, changes in Akt and GSK3 signalling are not restricted to a single disorder, and their contribution to specific behavioural symptoms or therapeutic effects may be modulated by broader changes in biologic contexts or signalling landscapes. Understanding these interactions may provide a better understanding of mental illnesses, leading to better efficacy of new therapeutic approaches.
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Affiliation(s)
- Jean-Martin Beaulieu
- Department of Psychiatry and Neuroscience, Faculty of Medicine, Université Laval, Centre de Recherche Université Laval Robert-Giffard (CRULRG), Québec, Canada.
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Zhang X, Nicholls PJ, Laje G, Sotnikova TD, Gainetdinov RR, Albert PR, Rajkowska G, Stockmeier CA, Speer MC, Steffens DC, Austin MC, McMahon FJ, Krishnan KRR, Garcia-Blanco MA, Caron MG. A functional alternative splicing mutation in human tryptophan hydroxylase-2. Mol Psychiatry 2011; 16:1169-76. [PMID: 20856248 PMCID: PMC3021090 DOI: 10.1038/mp.2010.99] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The brain serotonergic system has an essential role in the physiological functions of the central nervous system and dysregulation of serotonin (5-HT) homeostasis has been implicated in many neuropsychiatric disorders. The tryptophan hydroxylase-2 (TPH2) gene is the rate-limiting enzyme in brain 5-HT synthesis, and thus is an ideal candidate gene for understanding the role of dysregulation of brain serotonergic homeostasis. Here, we characterized a common, but functional single-nucleotide polymorphism (SNP rs1386493) in the TPH2 gene, which decreases efficiency of normal RNA splicing, resulting in a truncated TPH2 protein (TPH2-TR) by alternative splicing. TPH2-TR, which lacks TPH2 enzyme activity, dominant-negatively affects full-length TPH2 function, causing reduced 5-HT production. The predicted mRNA for TPH2-TR is present in postmortem brain of rs1386493 carriers. The rs13864923 variant does not appear to be overrepresented in either global or multiplex depression cohorts. However, in combination with other gene variants linked to 5-HT homeostasis, this variant may exhibit important epistatic influences.
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Affiliation(s)
- X Zhang
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA.
| | - P J Nicholls
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA
| | - G Laje
- Unit on Genetic Basis of Mood & Anxiety Disorders, National Institute of Mental Health, NIH, Bethesda, MD, USA
| | - T D Sotnikova
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA,Department of Neuroscience, Italian Institute of Technology, Genova, Italy
| | - R R Gainetdinov
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA,Department of Neuroscience, Italian Institute of Technology, Genova, Italy
| | - P R Albert
- OHRI (Neuroscience), University of Ottawa, Ottawa, ON, Canada
| | - G Rajkowska
- Department of Psychiatry and Human Behavior, University of Mississippi Medical Center, Jackson, MS, USA
| | - C A Stockmeier
- Department of Psychiatry and Human Behavior, University of Mississippi Medical Center, Jackson, MS, USA,Department of Psychiatry, Case Western Reserve University, Cleveland, OH, USA
| | - M C Speer
- Center for Human Genetics, Duke University Medical Center, Durham, NC, USA
| | - D C Steffens
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA
| | - M C Austin
- Department of Psychiatry and Human Behavior, University of Mississippi Medical Center, Jackson, MS, USA
| | - F J McMahon
- Unit on Genetic Basis of Mood & Anxiety Disorders, National Institute of Mental Health, NIH, Bethesda, MD, USA
| | - K R R Krishnan
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA
| | - M A Garcia-Blanco
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA
| | - M G Caron
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA,Department of Cell Biology, 487 CARL Building, Box 3287, Duke University Medical Center Durham, NC 27710, USA. E-mail:
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Huynh ML, Rivkin E, Mui R, Cordes SP. A tryptophan hydroxlyase 1 reporter that directs Cre recombinase extinguishable placental alkaline phosphatase expression in serotonergic (5-HT) neurons and peripheral tissues. Genesis 2011; 49:851-61. [DOI: 10.1002/dvg.20746] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Revised: 03/01/2011] [Accepted: 03/02/2011] [Indexed: 11/09/2022]
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Kulikov AV, Tikhonova MA, Osipova DV, Kulikov VA, Popova NK. Association between tryptophan hydroxylase-2 genotype and the antidepressant effect of citalopram and paroxetine on immobility time in the forced swim test in mice. Pharmacol Biochem Behav 2011; 99:683-7. [PMID: 21726574 DOI: 10.1016/j.pbb.2011.06.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Revised: 05/25/2011] [Accepted: 06/20/2011] [Indexed: 01/24/2023]
Abstract
Tryptophan hydroxylase-2 (TPH2) is the rate limiting enzyme of serotonin synthesis in the brain. The 1473G allele of the C1473G polymorphism in mTPH2 gene is associated with reduced enzyme activity and serotonin synthesis rate in the mouse brain. Here, the influence of the 1473G allele on the antidepressant effect of selective serotonin reuptake inhibitors (SSRIs), citalopram (2.5 or 5.0mg/kg) and paroxetine (5.0 or 10.0mg/kg), in the forced swim test was studied using B6-1473G and B6-1473C congenic mouse lines with the 1473G (decreased TPH2 activity) or 1473C (normal TPH2 activity) alleles, respectively, transferred to the genome of C57BL/6 mouse strain. Paroxetine (5.0 or 10.0mg/kg) and citalopram (2.5 or 5.0mg/kg) decreased immobility time in B6-1473C mice, while both doses of paroxetine and 2.5mg/kg of citaloprame did not alter immobility time in B6-1473G mice. However, 5.0mg/kg of citalopram reduced immobility in B6-1473G mice. The results provided genetic evidence of moderate association between 1473G allele and reduced sensitivity to SSRIs in mice.
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Affiliation(s)
- Alexander V Kulikov
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090, Novosibirsk, Russia.
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Abstract
Brain serotonergic circuitries interact with other neurotransmitter systems on a multitude of different molecular levels. In humans, as in other mammalian species, serotonin (5-HT) plays a modulatory role in almost every physiological function. Furthermore, serotonergic dysfunction is thought to be implicated in several psychiatric and neurodegenerative disorders. We describe the neuroanatomy and neurochemistry of brain serotonergic circuitries. The contribution of emergent in vivo imaging methods to the regional localization of binding site receptors and certain aspects of their functional connectivity in correlation to behavior is also discussed. 5-HT cell bodies, mainly localized in the raphe nuclei, send axons to almost every brain region. It is argued that the specificity of the local chemocommunication between 5-HT and other neuronal elements mainly depends on mechanisms regulating the extracellular concentration of 5-HT the diversity of high-affinity membrane receptors, and their specific transduction modalities.
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Affiliation(s)
- Yves Charnay
- Hôpitaux Universitaires de Genève, Département de Psychiatrie, Service de Neuropsychiatrie, Ch. Du Petit-Bel-Air, 2, CH-1225 Chêne-Bourg, Switzerland.
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Slof-Op ‘t Landt MCT, Meulenbelt I, Bartels M, Suchiman E, Middeldorp CM, Houwing-Duistermaat JJ, van Trier J, Onkenhout EJ, Vink JM, van Beijsterveldt CEM, Brandys MK, Sanders N, Zipfel S, Herzog W, Herpertz-Dahlmann B, Klampfl K, Fleischhaker C, Zeeck A, de Zwaan M, Herpertz S, Ehrlich S, van Elburg AA, Adan RAH, Scherag S, Hinney A, Hebebrand J, Boomsma DI, van Furth EF, Slagboom PE. Association study in eating disorders: TPH2 associates with anorexia nervosa and self-induced vomiting. GENES BRAIN AND BEHAVIOR 2010; 10:236-43. [DOI: 10.1111/j.1601-183x.2010.00660.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Nakamura K, Itoh K, Yoshimoto K, Sugimoto T, Fushiki S. Prenatal and lactational exposure to low-doses of bisphenol A alters brain monoamine concentration in adult mice. Neurosci Lett 2010; 484:66-70. [DOI: 10.1016/j.neulet.2010.08.021] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 08/03/2010] [Accepted: 08/06/2010] [Indexed: 12/20/2022]
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34
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Popova NK, Kulikov AV. Targeting tryptophan hydroxylase 2 in affective disorder. Expert Opin Ther Targets 2010; 14:1259-71. [DOI: 10.1517/14728222.2010.524208] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Siesser WB, Zhang X, Jacobsen JPR, Sotnikova TD, Gainetdinov RR, Caron MG. Tryptophan hydroxylase 2 genotype determines brain serotonin synthesis but not tissue content in C57Bl/6 and BALB/c congenic mice. Neurosci Lett 2010; 481:6-11. [PMID: 20600620 DOI: 10.1016/j.neulet.2010.06.035] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Revised: 06/09/2010] [Accepted: 06/11/2010] [Indexed: 11/29/2022]
Abstract
Tryptophan hydroxylase 2 (TPH2) catalyzes the rate-limiting step in the synthesis of brain serotonin (5-HT). In a previous report, a single nucleotide polymorphism in mTph2 (C1473G) reduced 5-HT synthesis by 55%. Mouse strains expressing the 1473C allele, such as C57Bl/6, have higher 5-HT synthesis rates than strains expressing the 1473G allele, such as BALB/c. Many studies have attributed strain differences to Tph2 genotype without ruling out the potential role of alterations in other genes. To test the role of the C1473G polymorphism in strain differences, we generated C57Bl/6 and BALB/c mice congenic for the Tph2 locus. We found that the 1473G allele reduced 5-HT synthesis in C57Bl/6 mice but had no effect on 5-HT tissue content except for a slight reduction (15%) in the frontal cortex. In BALB/c mice, the 1473C allele increased 5-HT synthesis but again did not affect 5-HT tissue content. At the same time, 5-hydroxyindoleacetic acid (5-HIAA) was significantly elevated in BALB/c congenic mice. In C57Bl/6 mice, there was no effect of genotype on 5-HIAA levels. BALB/c mice had lower expression of monoamine oxidase A and B than C57Bl/6 mice, but there was no effect of Tph2 genotype. On the tail suspension test, escitalopram treatment reduced immobility regardless of genotype. These data demonstrate that the C1473G polymorphism determines differences in 5-HT synthesis rates among strains but only minimally affects 5-HT tissue levels.
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36
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Quednow BB, Geyer MA, Halberstadt AL. Serotonin and Schizophrenia. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/s1569-7339(10)70102-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
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37
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Charnay Y, Léger L. Brain serotonergic circuitries. DIALOGUES IN CLINICAL NEUROSCIENCE 2010; 12:471-87. [PMID: 21319493 PMCID: PMC3181988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/06/2023]
Abstract
Brain serotonergic circuitries interact with other neurotransmitter systems on a multitude of different molecular levels. In humans, as in other mammalian species, serotonin (5-HT) plays a modulatory role in almost every physiological function. Furthermore, serotonergic dysfunction is thought to be implicated in several psychiatric and neurodegenerative disorders. We describe the neuroanatomy and neurochemistry of brain serotonergic circuitries. The contribution of emergent in vivo imaging methods to the regional localization of binding site receptors and certain aspects of their functional connectivity in correlation to behavior is also discussed. 5-HT cell bodies, mainly localized in the raphe nuclei, send axons to almost every brain region. It is argued that the specificity of the local chemocommunication between 5-HT and other neuronal elements mainly depends on mechanisms regulating the extracellular concentration of 5-HT the diversity of high-affinity membrane receptors, and their specific transduction modalities.
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Affiliation(s)
- Yves Charnay
- Hôpitaux Universitaires de Genève, Département de Psychiatrie, Service de Neuropsychiatrie, Ch. Du Petit-Bel-Air, 2, CH-1225 Chêne-Bourg, Switzerland.
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Acute tryptophan depletion in C57BL/6 mice does not induce central serotonin reduction or affective behavioural changes. Neurochem Int 2009; 56:21-34. [PMID: 19716853 DOI: 10.1016/j.neuint.2009.08.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Accepted: 08/24/2009] [Indexed: 11/22/2022]
Abstract
Acute tryptophan depletion is extensively used to investigate the implication of serotonin in the onset of depressive disorders. In rats, it lowers peripheral tryptophan and decreases central serotonin concentrations. We aimed to establish the rat model of acute tryptophan depletion in the mouse for potential application as serotonin challenge tool in genetic mouse models of depression. Pharmacokinetic and behavioural effects of a tryptophan-free diet were examined in Swiss and C57BL/6 mice. Peripheral amino acids were measured and central tryptophan and serotonin concentrations were compared with anxiety and depression-like behaviour in the elevated zero-maze, forced swimming test or tail suspension test. While acute tryptophan depletion resulted in a 74% reduction of the plasma ratio tryptophan to the sum of other large neutral amino acids in Swiss mice 1h after administration (2x10 ml/kg, 30 min interval), there was only a 40% reduction in C57BL/6 mice. The latter did not show anxiety in the elevated zero-maze or increased immobility in the forced swimming test or tail suspension test. A higher dose (2x20 ml/kg) with a longer interval (60 min) reduced the ratio with 68% in C57BL/6 mice, lowered hippocampal serotonin turnover and had no functional effect when tested in the elevated zero-maze and forced swimming test. These findings have important implications for the use of acute tryptophan depletion in general and in particular for its application in mice. Although in healthy mice no clear central serotonin or functional effects were observed, further research is indicated using mice with pre-existing serotonin dysfunction, as they might be more vulnerable to acute tryptophan depletion.
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Serretti A, Liappas I, Mandelli L, Albani D, Forloni G, Malitas P, Piperi C, Politis A, Tzavellas EO, Papadopoulou-Daifoti Z, Zisaki A, Prato F, Batelli S, Polito L, De Ronchi D, Kalofoutis A. TPH2 gene variants and anxiety during alcohol detoxification outcome. Psychiatry Res 2009; 167:106-14. [PMID: 19361870 DOI: 10.1016/j.psychres.2007.12.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2007] [Revised: 11/16/2007] [Accepted: 12/05/2007] [Indexed: 10/20/2022]
Abstract
Clinical outcome of alcoholism may be partly under genetic control. The serotonergic system is involved in alcohol intake, and it has been widely investigated in alcohol dependence. Recently, attention has been focused on the neuronal tryptophan hydroxylase 2 gene (TPH2). TPH2 variants have been consistently associated with anxiety-related traits; since anxiety is critical for alcohol dependence treatment, in the present paper we investigated 9 SNPs within the THP2 gene in anxiety symptoms during the detoxification procedure. The sample comprised 68 alcohol-dependent patients who where evaluated with the Hamilton Rating Scale for Anxiety, before and after the detoxification procedure. Other psychopathological indicators of outcome, such as depression and anxiety sub-features were also investigated. We did not observe a role for TPH2 variants in the efficacy of treatment in relieving anxiety and other psychopathological symptoms. However, a haplotype that included the promoter rs4570625 polymorphism (associated with anxiety-related traits in previous studies) showed an association with the severity of anxiety symptoms on admission. This preliminary finding, although obtained on a small sample, may provide further support for a role of the TPH2 gene in emotional behaviors. Furthermore, the present study suggests the possible functional significance of the promoter rs4570625 polymorphism. The present preliminary results are of interest in alcoholism, given that comorbidity with anxiety represents a critical problem in treatment settings and response to detoxification.
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Nobile M, Rusconi M, Bellina M, Marino C, Giorda R, Carlet O, Vanzin L, Molteni M, Battaglia M. The influence of family structure, the TPH2 G-703T and the 5-HTTLPR serotonergic genes upon affective problems in children aged 10-14 years. J Child Psychol Psychiatry 2009; 50:317-25. [PMID: 19175813 DOI: 10.1111/j.1469-7610.2008.01958.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Both genetic and psychosocial risk factors influence the risk for depression in development. While the impacts of family structure and of serotonergic polymorphisms upon individual differences for affective problems have been investigated separately, they have never been considered together in a gene-environment interplay perspective. METHODS We examined the effects of family structure and two serotonergic polymorphisms (the TPH2 G-703T and the 5-HTTLPR) upon depressive symptoms assessed by the new CBCL/6-18 DSM-oriented Affective Problems scale in a general population sample of 607 Italian children aged 10-14 years. RESULTS Belonging to 'one-parent' families, the TPH2 G-703T 'G variant', and the 5-HTTLPR 'short' alleles were associated - both alone and in apparent gene-by-environment interaction - with higher Affective Problems scores. As predicted by quantitative genetics theory, both polymorphisms contributed with a small effect size, while 'family structure' had a moderate effect size. CONCLUSIONS A putative hazard factor impinging on individual risk at the family-wide level, namely family structure, appears to act interactively with two pivotal serotonergic genes in heightening risk for Affective Problems. Although it remains to be demonstrated that belonging to a one- rather than a two-parent family has true environmental causal effects on Affective Problems, these data may contribute to identify/prevent risk for depression in childhood.
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Affiliation(s)
- Maria Nobile
- Department of Child Psychiatry, Eugenio Medea Scientific Institute, Bosisio Parini, Italy.
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41
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Beaulieu JM, Gainetdinov RR, Caron MG. Akt/GSK3 Signaling in the Action of Psychotropic Drugs. Annu Rev Pharmacol Toxicol 2009; 49:327-47. [DOI: 10.1146/annurev.pharmtox.011008.145634] [Citation(s) in RCA: 442] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Raul R. Gainetdinov
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina 27710;
- Current affiliation: Department of Neuroscience and Brain Technology, Italian Institute of Technology, Genova, Italy;
| | - Marc G. Caron
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina 27710;
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Wojnar M, Brower KJ, Strobbe S, Ilgen M, Matsumoto H, Nowosad I, Sliwerska E, Burmeister M. Association between Val66Met brain-derived neurotrophic factor (BDNF) gene polymorphism and post-treatment relapse in alcohol dependence. Alcohol Clin Exp Res 2009; 33:693-702. [PMID: 19170664 DOI: 10.1111/j.1530-0277.2008.00886.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The purpose of this study was to examine relationships between genetic markers of central serotonin (5-HT) and dopamine function, and risk for post-treatment relapse, in a sample of alcohol-dependent patients. METHODS The study included 154 patients from addiction treatment programs in Poland, who met DSM-IV criteria for alcohol dependence. After assessing demographics, severity of alcohol use, suicidality, impulsivity, depression, hopelessness, and severity of alcohol use at baseline, patients were followed for approximately 1 year to evaluate treatment outcomes. Genetic polymorphisms in several genes (TPH2, SLC6A4, HTR1A, HTR2A, COMT, and BDNF) were tested as predictors of relapse (defined as any drinking during follow-up) while controlling for baseline measures. RESULTS Of 154 eligible patients, 123 (80%) completed follow-up and 48% (n = 59) of these individuals relapsed. Patients with the Val allele in the Val66Met BDNF polymorphism and the Met allele in the Val158Met COMT polymorphism were more likely to relapse. Only the BDNF Val/Val genotype predicted post-treatment relapse [odds ratio (OR) = 2.62; p = 0.019], and time to relapse (OR = 2.57; p = 0.002), after adjusting for baseline measures and other significant genetic markers. When the analysis was restricted to patients with a family history of alcohol dependence (n = 73), the associations between the BDNF Val/Val genotype and relapse (OR = 5.76, p = 0.0045) and time to relapse (hazard ratio = 4.93, p = 0.001) were even stronger. CONCLUSIONS The Val66Met BDNF gene polymorphism was associated with a higher risk and earlier occurrence of relapse among patients treated for alcohol dependence. The study suggests a relationship between genetic markers and treatment outcomes in alcohol dependence. Because a large number of statistical tests were conducted for this study and the literature on genetics and relapse is so novel, the results should be considered as hypothesis generating and need to be replicated in independent studies.
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Affiliation(s)
- Marcin Wojnar
- Department of Psychiatry, University of Michigan, Ann Arbor, Michigan 48109, USA.
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43
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Neal KB, Parry LJ, Bornstein JC. Strain-specific genetics, anatomy and function of enteric neural serotonergic pathways in inbred mice. J Physiol 2008; 587:567-86. [PMID: 19064621 DOI: 10.1113/jphysiol.2008.160416] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Serotonin (5-HT) powerfully affects small intestinal motility and 5-HT-immunoreactive (IR) neurones are highly conserved between species. 5-HT synthesis in central neurones and gastrointestinal mucosa depends on tissue-specific isoforms of the enzyme tryptophan hydroxylase (TPH). RT-PCR identified strain-specific expression of a polymorphism (1473C/G) of the tph2 gene in longitudinal muscle-myenteric plexus preparations of C57Bl/6 and Balb/c mice. The former expressed the high-activity C allele, the latter the low-activity G allele. Confocal microscopy was used to examine close contacts between 5-HT-IR varicosities and myenteric neurones immunoreactive for neuronal nitric oxide synthase (NOS) or calretinin in these two strains. Significantly more close contacts were identified to NOS- (P < 0.05) and calretinin-IR (P < 0.01) neurones in C57Bl/6 jejunum (NOS 1.6 +/- 0.3, n = 52; calretinin 5.2 +/- 0.4, n = 54), than Balb/c jejunum (NOS 0.9 +/- 0.2, n = 78; calretinin 3.5 +/- 0.3, n = 98). Propagating contractile complexes (PCCs) were identified in the isolated jejunum by constructing spatiotemporal maps from video recordings of cannulated segments in vitro. These clusters of contractions usually arose towards the anal end and propagated orally. Regular PCCs were initiated at intraluminal pressures of 6 cmH(2)O, and abolished by tetrodotoxin (1 microm). Jejunal PCCs from C57Bl/6 mice were suppressed by a combination of granisetron (1 microm, 5-HT(3) antagonist) and SB207266 (10 nm, 5-HT(4) antagonist), but PCCs from Balb/c mice were unaffected. There were, however, no strain-specific differences in sensitivity of longitudinal muscle contractions to exogenous 5-HT or blockade of 5-HT(3) and 5-HT(4) receptors. These data associate a genetic difference with significant structural and functional consequences for enteric neural serotonergic pathways in the jejunum.
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Affiliation(s)
- Kathleen B Neal
- Department of Physiology, The University of Melbourne, Parkville, Victoria, Australia.
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Haavik J, Blau N, Thöny B. Mutations in human monoamine-related neurotransmitter pathway genes. Hum Mutat 2008; 29:891-902. [PMID: 18444257 DOI: 10.1002/humu.20700] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Biosynthesis and metabolism of serotonin and catecholamines involve at least eight individual enzymes that are mainly expressed in tissues derived from the neuroectoderm, e.g., the central nervous system (CNS), pineal gland, adrenal medulla, enterochromaffin tissue, sympathetic nerves, and ganglia. Some of the enzymes appear to have additional biological functions and are also expressed in the heart and various other internal organs. The biosynthetic enzymes are tyrosine hydroxylase (TH), tryptophan hydroxylases type 1 and 2 (TPH1, TPH2), aromatic amino acid decarboxylase (AADC), dopamine beta-hydroxylase (DbetaH), and phenylethanolamine N-methyltransferase (PNMT), and the specific catabolic enzymes are monoamine oxidase A (MAO-A) and catechol O-methyltransferase (COMT). For the TH, DDC, DBH, and MAOA genes, many single nucleotide polymorphisms (SNPs) with unknown function, and small but increasing numbers of cases with autosomal recessive mutations have been recognized. For the remaining genes (TPH1, TPH2, PNMT, and COMT) several different genetic markers have been suggested to be associated with regulation of mood, pain perception, and aggression, as well as psychiatric disturbances such as schizophrenia, depression, suicidality, and attention deficit/hyperactivity disorder. The genetic markers may either have a functional role of their own, or be closely linked to other unknown functional variants. In the future, molecular testing may become important for the diagnosis of such conditions. Here we present an overview on mutations and polymorphisms in the group of genes encoding monoamine neurotransmitter metabolizing enzymes. At the same time we propose a unified nomenclature for the nucleic acid aberrations in these genes. New variations or details on mutations will be updated in the Pediatric Neurotransmitter Disorder Data Base (PNDDB) database (www.bioPKU.org).
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Affiliation(s)
- Jan Haavik
- Department of Biomedicine, University of Bergen, Norway
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Abstract
A considerable body of evidence suggests the involvement of serotonin neurotransmission in the pathogenesis of panic disorder. Research on pathways and functions of tryptophan, an essential amino acid converted into serotonin, may advance our understanding of serotonergic actions in panic disorder and related phenomena. The investigative approaches in this field include manipulations of tryptophan availability as well as genetic association and functional brain imaging studies. In this review we examine the principle findings of these studies and propose further research directions.
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Affiliation(s)
- Eduard Maron
- Research Department of Mental Health, The North Estonian Regional Hospital, Psychiatry Clinic, Tallinn, Estonia
- Department of Psychiatry, University of Tartu, Tartu, Estonia
- Estonian Genome Project, University of Tartu, Estonia
| | - Jakov Shlik
- Department of Psychiatry, University of Ottawa, Ottawa, Ontario, Canada
| | - David J. Nutt
- Department of Community Based Medicine, Psychopharmacology Unit, University of Bristol, U.K
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Reply to Belmaker et al.: GSK3 haploinsufficiency results in lithium-like effects in the forced-swim test. Proc Natl Acad Sci U S A 2008. [DOI: 10.1073/pnas.0803026105] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Murphy KL, Zhang X, Gainetdinov RR, Beaulieu JM, Caron MG. A regulatory domain in the N terminus of tryptophan hydroxylase 2 controls enzyme expression. J Biol Chem 2008; 283:13216-24. [PMID: 18339632 PMCID: PMC2442358 DOI: 10.1074/jbc.m706749200] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2007] [Revised: 03/12/2008] [Indexed: 01/10/2023] Open
Abstract
Serotonin is involved in a variety of physiological processes in the central nervous system and the periphery. As the rate-limiting enzyme in serotonin synthesis, tryptophan hydroxylase plays an important role in modulating these processes. Of the two variants of tryptophan hydroxylase, tryptophan hydroxylase 2 (TPH2) is expressed predominantly in the central nervous system, whereas tryptophan hydroxylase 1 (TPH1) is expressed mostly in peripheral tissues. Although the two enzymes share considerable sequence homology, the regulatory domain of TPH2 contains an additional 41 amino acids at the N terminus that TPH1 lacks. Here we show that the extended TPH2 N-terminal domain contains a unique sequence involved in the regulation of enzyme expression. When expressed in cultured mammalian cells, TPH2 is synthesized less efficiently and is also less stable than TPH1. Removal of the unique portion of the N terminus of TPH2 results in expression of the enzyme at a level similar to that of TPH1, whereas protein chimeras containing this fragment are expressed at lower levels than their wild-type counterparts. We identify a region centered on amino acids 10-20 that mediates the bulk of this effect. We also demonstrate that phosphorylation of serine 19, a protein kinase A consensus site located in this N-terminal domain, results in increased TPH2 stability and consequent increases in enzyme output in cell culture systems. Because this domain is unique to TPH2, these data provide evidence for selective regulation of brain serotonin synthesis.
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Affiliation(s)
- Karen L Murphy
- Department of Neurobiology and Cell Biology, Duke University Medical Center, Durham, North Carolina 27710, USA
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Holmes A. Genetic variation in cortico-amygdala serotonin function and risk for stress-related disease. Neurosci Biobehav Rev 2008; 32:1293-314. [PMID: 18439676 DOI: 10.1016/j.neubiorev.2008.03.006] [Citation(s) in RCA: 201] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Accepted: 02/20/2008] [Indexed: 01/09/2023]
Abstract
The serotonin system is strongly implicated in the pathophysiology and therapeutic alleviation of stress-related disorders such as anxiety and depression. Serotonergic modulation of the acute response to stress and the adaptation to chronic stress is mediated by a myriad of molecules controlling serotonin neuron development (Pet-1), synthesis (tryptophan hydroxylase 1 and 2 isozymes), packaging (vesicular monoamine transporter 2), actions at presynaptic and postsynaptic receptors (5-HT1A, 5-HT1B, 5-HT2A, 5-HT2C, 5-HT3A, 5-HT4, 5-HT5A, 5-HT6, 5-HT7), reuptake (serotonin transporter), and degradation (monoamine oxidase A). A growing body of evidence from preclinical rodents models, and especially genetically modified mice and inbred mouse strains, has provided significant insight into how genetic variation in these molecules can affect the development and function of a key neural circuit between the dorsal raphe nucleus, medial prefrontal cortex and amygdala. By extension, such variation is hypothesized to have a major influence on individual differences in the stress response and risk for stress-related disease in humans. The current article provides an update on this rapidly evolving field of research.
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Affiliation(s)
- Andrew Holmes
- Section on Behavioral Science and Genetics, Laboratory for Integrative Neuroscience, National Institute on Alcoholism and Alcohol Abuse, NIH, 5625 Fishers Lane Room 2N09, Rockville, MD 20852-9411, USA.
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Inhibition of serotonin but not norepinephrine transport during development produces delayed, persistent perturbations of emotional behaviors in mice. J Neurosci 2008; 28:199-207. [PMID: 18171937 DOI: 10.1523/jneurosci.3973-07.2008] [Citation(s) in RCA: 225] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Serotonin (5-HT) acts as a neurotransmitter, but also modulates brain maturation during early development. The demonstrated influence of genetic variants on brain function, personality traits, and susceptibility to neuropsychiatric disorders suggests a critical importance of developmental mechanisms. However, little is known about how and when developmentally perturbed 5-HT signaling affects circuitry and resulting behavior. The 5-HT transporter (5-HTT) is a key regulator of extracellular 5-HT levels and we used pharmacologic strategies to manipulate 5-HTT function during development and determine behavioral consequences. Transient exposure to the 5-HTT inhibitors fluoxetine, clomipramine, and citalopram from postnatal day 4 (P4) to P21 produced abnormal emotional behaviors in adult mice. Similar treatment with the norepinephrine transporter (NET) inhibitor, desipramine, did not adversely affect adult behavior, suggesting that 5-HT and norepinephrine (NE) do not share the same effects on brain development. Shifting our period of treatment/testing to P90/P185 failed to mimic the effect of earlier exposure, demonstrating that 5-HT effects on adult behavior are developmentally specific. We have hypothesized that early-life perturbations of 5-HT signaling affect corticolimbic circuits that do not reach maturity until the peri-adolescent period. In support of this idea, we found that abnormal behaviors resulting from postnatal fluoxetine exposure have a post-pubescent onset and persist long after reaching adult age. A better understanding of the underlying 5-HT sensitive circuits and how they are perturbed should lead to new insights into how various genetic polymorphisms confer their risk to carriers. Furthermore, these studies should help determine whether in utero exposure to 5-HTT blocking drugs poses a risk for behavioral abnormalities in later life.
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A simple two step procedure for purification of the catalytic domain of chicken tryptophan hydroxylase 1 in a form suitable for crystallization. Protein Expr Purif 2008; 57:116-26. [DOI: 10.1016/j.pep.2007.10.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Revised: 10/12/2007] [Accepted: 10/18/2007] [Indexed: 11/24/2022]
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