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Bîlc MI, Iacob A, Szekely-Copîndean RD, Kiss B, Ștefan MG, Mureșan RC, Pop CF, Pițur S, Szentágotai-Tătar A, Vulturar R, MacLeod C, Miu AC. Serotonin and emotion regulation: the impact of tryptophan depletion on emotional experience, neural and autonomic activity. COGNITIVE, AFFECTIVE & BEHAVIORAL NEUROSCIENCE 2023; 23:1414-1427. [PMID: 37430145 DOI: 10.3758/s13415-023-01116-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/09/2023] [Indexed: 07/12/2023]
Abstract
The involvement of serotonin in emotion and psychopathology has been extensively examined. Studies using acute tryptophan depletion (ATD) have found limited effects on mood and aggression, and one of the explanations suggests that serotonin may be involved in higher-order functions, such as emotion regulation. However, there is very limited evidence for this hypothesis. The present study investigated the impact of ATD on emotion regulation in a double-blind, placebo-controlled, crossover design. A sample of psychiatrically healthy men (N = 28) completed a cognitive task assessing reappraisal ability (i.e., the success of using reappraisal, an emotion regulation strategy, to modulate emotional responses), following ATD and placebo. EEG frontal activity and asymmetry, as well as heart-rate variability (HRV), also were assessed in the reappraisal task. Both frequentist and Bayesian methods were employed for statistical analysis. Results indicated that ATD reduced plasma tryptophan, and reappraisal was effective in modulating emotional experience in the emotion regulation task. However, ATD had no significant effect on reappraisal ability, frontal activity, and HRV. These results offer direct and compelling evidence that decreasing serotonin synthesis through ATD does not alter an emotion regulation ability that is considered crucial in mood and aggression and has been linked with transdiagnostic risk of psychopathology.
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Affiliation(s)
- Mirela I Bîlc
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania
- Institute of Medical Psychology, Medical Faculty, Otto-von-Guericke University of Magdeburg, Magdeburg, Germany
| | - Alexandra Iacob
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania
| | - Raluca D Szekely-Copîndean
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania
- Department of Social and Human Research, Romanian Academy, Cluj-Napoca, Romania
| | - Béla Kiss
- Department of Toxicology, Faculty of Pharmacy, "Iuliu Hațieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Maria-Georgia Ștefan
- Department of Toxicology, Faculty of Pharmacy, "Iuliu Hațieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Raul C Mureșan
- Department of Experimental and Theoretical Neuroscience, Transylvanian Institute of Neuroscience, Cluj-Napoca, Romania
- STAR-UBB Institute, Babeș-Bolyai University, Cluj-Napoca, Romania
| | - Claudia Felicia Pop
- Nursing Discipline, Department Mother and Child, "Iuliu Hațieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Simina Pițur
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania
| | - Aurora Szentágotai-Tătar
- Department of Clinical Psychology and Psychotherapy, Babeș-Bolyai University, Cluj-Napoca, Romania
| | - Romana Vulturar
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania.
- Department of Molecular Sciences, "Iuliu Hațieganu" University of Medicine and Pharmacy, 6 Pasteur Street, 400349, Cluj-Napoca, Romania.
| | - Colin MacLeod
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania
- Centre for the Advancement of Research on Emotion, School of Psychological Science, The University of Western Australia, Crawley, Australia
| | - Andrei C Miu
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania.
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Romero-Martínez Á, Sarrate-Costa C, Moya-Albiol L. Reactive vs proactive aggression: A differential psychobiological profile? Conclusions derived from a systematic review. Neurosci Biobehav Rev 2022; 136:104626. [PMID: 35331815 DOI: 10.1016/j.neubiorev.2022.104626] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 02/11/2022] [Accepted: 03/15/2022] [Indexed: 10/18/2022]
Abstract
INTRODUCTION Scholars have established subcategories of aggressive behavior in order to better understand this construct. Specifically, a classification based on motivational underpinnings makes it possible to differentiate between reactive and proactive aggression. Whereas reactive aggression is characterized by emotional lability, which means it is prone to impulsive reactions after provocation, proactive aggression is driven by low emotionality and high levels of instrumentality to obtain benefits. Some authors have conceived these two types as having a dichotomous nature, but others argue against this conceptualization, considering a complementary model more suitable. Hence, neuroscientific research might help to clarify discussions about their nature because biological markers do not present the same biases as psychological instruments. AIM The main objective of this study was to carry out a systematic review of studies that assess underlying biological markers (e.g., genes, brain, psychophysiological, and hormonal) of reactive and proactive aggression. METHODS To carry out this review, we followed PRISMA quality criteria for reviews, using five digital databases complemented by hand-searching. RESULTS The reading of 3993 abstracts led to the final inclusion of 157 papers that met all the inclusion criteria. The studies included allow us to conclude that heritability accounted for approximately 45% of the explained variance in both types of aggression, with 60% shared by both, especially, for overt and physical expression forms, and 10% specific to each type. Regarding allelic risk factors, whereas low functioning variants affecting serotonin transport and monoaminoxidase increased the risk of reactive aggression, high functioning variants were associated with proactive aggression. Furthermore, brain analysis revealed an overlap between the two types of aggression and alterations in the volume of the amygdala and temporal cortex. Moreover, high activation of the medial prefrontal cortex (PFC) facilitated proneness to both types of aggression equally. Whereas stimulation of the right ventrolateral (VLPFC) and dorsolateral (DLPFC) reduced proneness to aggression, inhibition of the left DLPFC increased it. Finally, psychophysiological and hormonal correlates in general did not clearly differentiate between the two types because they were equally related to each type (e.g., low basal cortisol and vagal variability in response to acute stress) CONCLUSIONS: This study reinforces the complementary model of both types of aggression instead of a dichotomous model. Additionally, this review also offers background about several treatments (i.e., pharmacological, non-invasive brain techniques…) to reduce aggression proneness.
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Tryptophan modulation in individuals with attention deficit hyperactivity disorder: a systematic review. J Neural Transm (Vienna) 2022; 129:361-377. [PMID: 35286460 PMCID: PMC9007797 DOI: 10.1007/s00702-022-02478-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 02/11/2022] [Indexed: 12/28/2022]
Abstract
The serotonergic system is implicated in ADHD, but the impact of serotonin’s precursor molecule, tryptophan, on ADHD symptomology remains unclear. Systematic searches of randomised controlled trials with an experimental tryptophan intervention in children and adults with ADHD identified 14 studies measuring core and related symptoms of the condition. Risk of bias was assessed using the Cochrane Risk of Bias tool. The 14 studies all used acute tryptophan depletion procedures, and most did not investigate core ADHD symptoms (inattention, impulsivity, hyperactivity) as primary outcome measures. Only two studies examined attention and revealed mixed effects of tryptophan. Similar effects were found for impulsivity in a small number of studies. No studies investigated hyperactivity. Most studies focused on reactive aggression, but samples were heterogenous and small, rendering potential meta-analyses inconclusive or misleading. However, the narrative analysis indicates tryptophan interventions may impact reactive aggression. More research is needed on the effect of tryptophan modulation on core ADHD symptoms, especially in adults, using more diverse samples to determine potential as an intervention. From current data, tryptophan modulation appears to alter aggressive behaviour in ADHD; however, the available studies were insufficient for the planned meta-analysis.
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Tronstad C, Amini M, Bach DR, Martinsen OG. Current trends and opportunities in the methodology of electrodermal activity measurement. Physiol Meas 2022; 43. [PMID: 35090148 DOI: 10.1088/1361-6579/ac5007] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 01/28/2022] [Indexed: 11/12/2022]
Abstract
Electrodermal activity (EDA) has been measured in the laboratory since the late 1800s. Although the influence of sudomotor nerve activity and the sympathetic nervous system on EDA is well established, the mechanisms underlying EDA signal generation are not completely understood. Owing to simplicity of instrumentation and modern electronics, these measurements have recently seen a transfer from the laboratory to wearable devices, sparking numerous novel applications while bringing along both challenges and new opportunities. In addition to developments in electronics and miniaturization, current trends in material technology and manufacturing have sparked innovations in electrode technologies, and trends in data science such as machine learning and sensor fusion are expanding the ways that measurement data can be processed and utilized. Although challenges remain for the quality of wearable EDA measurement, ongoing research and developments may shorten the quality gap between wearable EDA and standardized recordings in the laboratory. In this topical review, we provide an overview of the basics of EDA measurement, discuss the challenges and opportunities of wearable EDA, and review recent developments in instrumentation, material technology, signal processing, modeling and data science tools that may advance the field of EDA research and applications over the coming years.
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Affiliation(s)
- Christian Tronstad
- Department of Clinical and Biomedical Engineering, Oslo University Hospital, Sognsvannsveien 20, Oslo, 0372, NORWAY
| | - Maryam Amini
- Physics, University of Oslo Faculty of Mathematics and Natural Sciences, Sem Sælands vei 24, Oslo, 0371, NORWAY
| | - Dominik R Bach
- Wellcome Centre for Human Neuroimaging, University College London, 12 Queen Square, London, London, WC1N 3AZ, UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND
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Mehta A, Kumar Ratre Y, Sharma K, Soni VK, Tiwari AK, Singh RP, Dwivedi MK, Chandra V, Prajapati SK, Shukla D, Vishvakarma NK. Interplay of Nutrition and Psychoneuroendocrineimmune Modulation: Relevance for COVID-19 in BRICS Nations. Front Microbiol 2021; 12:769884. [PMID: 34975797 PMCID: PMC8718880 DOI: 10.3389/fmicb.2021.769884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 11/16/2021] [Indexed: 11/21/2022] Open
Abstract
The consequences of COVID-19 are not limited to physical health deterioration; the impact on neuropsychological well-being is also substantially reported. The inter-regulation of physical health and psychological well-being through the psychoneuroendocrineimmune (PNEI) axis has enduring consequences in susceptibility, treatment outcome as well as recuperation. The pandemic effects are upsetting the lifestyle, social interaction, and financial security; and also pose a threat through perceived fear. These consequences of COVID-19 also influence the PNEI system and wreck the prognosis. The nutritional status of individuals is also reported to have a determinative role in COVID-19 severity and convalescence. In addition to energetic demand, diet also provides precursor substances [amino acids (AAs), vitamins, etc.] for regulators of the PNEI axis such as neurotransmitters (NTs) and immunomodulators. Moreover, exaggerated immune response and recovery phase of COVID-19 demand additional nutrient intake; widening the gap of pre-existing undernourishment. Mushrooms, fresh fruits and vegetables, herbs and spices, and legumes are few of such readily available food ingredients which are rich in protein and also have medicinal benefits. BRICS nations have their influences on global development and are highly impacted by a large number of confirmed COVID-19 cases and deaths. The adequacy and access to healthcare are also low in BRICS nations as compared to the rest of the world. Attempt to combat the COVID-19 pandemic are praiseworthy in BRICS nations. However, large population sizes, high prevalence of undernourishment (PoU), and high incidence of mental health ailments in BRICS nations provide a suitable landscape for jeopardy of COVID-19. Therefore, appraising the interplay of nutrition and PNEI modulation especially in BRICS countries will provide better understanding; and will aid in combat COVID-19. It can be suggested that the monitoring will assist in designing adjunctive interventions through medical nutrition therapy and psychopsychiatric management.
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Affiliation(s)
- Arundhati Mehta
- Department of Biotechnology, Guru Ghasidas Vishwavidyalaya, Bilaspur, India
| | | | - Krishna Sharma
- Department of Psychology, Government Bilasa Girls Post Graduate Autonomous College, Bilaspur, India
| | - Vivek Kumar Soni
- Department of Biotechnology, Guru Ghasidas Vishwavidyalaya, Bilaspur, India
| | - Atul Kumar Tiwari
- Department of Zoology, Bhanwar Singh Porte Government Science College, Pendra, India
| | - Rajat Pratap Singh
- Department of Biotechnology, Guru Ghasidas Vishwavidyalaya, Bilaspur, India
| | - Mrigendra Kumar Dwivedi
- Department of Biochemistry, Government Nagarjuna Post Graduate College of Science, Raipur, India
| | - Vikas Chandra
- Department of Biotechnology, Guru Ghasidas Vishwavidyalaya, Bilaspur, India
| | | | - Dhananjay Shukla
- Department of Biotechnology, Guru Ghasidas Vishwavidyalaya, Bilaspur, India
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Akhrif A, Roy A, Peters K, Lesch KP, Romanos M, Schmitt-Böhrer A, Neufang S. REVERSE phenotyping-Can the phenotype following constitutive Tph2 gene inactivation in mice be transferred to children and adolescents with and without adhd? Brain Behav 2021; 11:e02054. [PMID: 33523602 PMCID: PMC8119824 DOI: 10.1002/brb3.2054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 01/12/2021] [Accepted: 01/18/2021] [Indexed: 12/17/2022] Open
Abstract
INTRODUCTION Experimental models of neuropsychiatric disorders, for example, ADHD, are used to mimic specific phenotypic traits of a complex human disorder. However, it remains unresolved to what extent the animal phenotype reflects the specific human trait. The null mutant mouse of the serotonin-synthesizing tryptophan hydroxylase-2 (Tph2-/- ) gene has been proposed as experimental model for ADHD with high face validity for impulsive, aggressive, and anxious behaviors. To validate this ADHD-like model, we examined the Tph2-/- phenotype in humans when considering allelic variation of TPH2 function ("reverse phenotyping"). METHODS 58 participants (6 females, 8-18 years) were examined, of whom 32 were diagnosed with ADHD. All participants were phenotyped for impulsivity, aggression, and anxiety using questionnaires, behavioral tests, and MRI scanning while performing the 4-choice serial reaction time task. Additionally, participants were genotyped for the TPH2 G-703T (rs4570625) polymorphism. To analyze the relation between TPH2 G-703T variants and the impulsive/aggressive/anxious phenotype, mediation analyses were performed using behavioral and MRI data as potential mediators. RESULTS We found that the relation between TPH2 G-703T and aggression as part of the reverse Tph2- /- phenotype was mediated by structure and function of the right middle and inferior frontal gyrus. CONCLUSION At the example of trait aggression, our results support the assumption that the Tph2 null mutant mouse reflects the TPH2 G-703T-dependent phenotype in humans. Additionally, we conclude that "reverse phenotyping" is a promising method to validate experimental models and human findings for refined analysis of disease mechanisms.
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Affiliation(s)
- Atae Akhrif
- Department of Child and Adolescent Psychiatry, Center of Mental Health, University of Würzburg, Würzburg, Germany.,Comparative Psychology, Institute of Experimental Psychology, Heinrich-Heine University of Düsseldorf, Düsseldorf, Germany
| | - Arunima Roy
- The Royal's Institute of Mental Health Research, University of Ottawa, Ottawa, Canada
| | - Katharina Peters
- Department of Child and Adolescent Psychiatry, Center of Mental Health, University of Würzburg, Würzburg, Germany
| | - Klaus-Peter Lesch
- Division of Molecular Psychiatry, Center of Mental Health, University of Würzburg, Würzburg, Germany.,Laboratory of Psychiatric Neurobiology, Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia.,Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Marcel Romanos
- Department of Child and Adolescent Psychiatry, Center of Mental Health, University of Würzburg, Würzburg, Germany
| | - Angelika Schmitt-Böhrer
- Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University of Würzburg, Würzburg, Germany
| | - Susanne Neufang
- Comparative Psychology, Institute of Experimental Psychology, Heinrich-Heine University of Düsseldorf, Düsseldorf, Germany.,Department of Psychiatry and Psychotherapy, Medical Faculty Heinrich, Heine University of Düsseldorf, Düsseldorf, Germany
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Stewart RM, Wong JWY, Mahfouda S, Morandini HAE, Rao P, Runions KC, Zepf FD. Acute Tryptophan Depletion Moja-De: A Method to Study Central Nervous Serotonin Function in Children and Adolescents. Front Psychiatry 2020; 10:1007. [PMID: 32210845 PMCID: PMC7067742 DOI: 10.3389/fpsyt.2019.01007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Accepted: 12/20/2019] [Indexed: 11/13/2022] Open
Abstract
Serotonin (5-HT) is widely implicated as a key neurotransmitter relevant to a range of psychiatric disorders and psychological processes. The role of central nervous 5-HT function underlying these processes can be examined through serotonergic challenge methodologies. Acute tryptophan depletion (ATD) is a key challenge method whereby a diminished dietary intake of tryptophan-the amino acid precursor to brain 5-HT synthesis-results in temporary diminished central nervous 5-HT synthesis. While this particular methodology has been used in adult populations, it was only recently that modifications were made to enable the use of ATD in child and adolescent populations. Additionally, the Moja-De modification of the ATD challenge methodology has demonstrated benefits over other ATD techniques used previously. The aim of this protocol paper is to describe the ATD Moja-De methodology in detail, its benefits, as well as studies that have been conducted to validate the procedure in child and adolescent samples. The ATD Moja-De protocol provides a potential methodology for investigating the role of central nervous 5-HT via manipulation of brain tryptophan availability in human psychopathology from a developmental viewpoint.
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Affiliation(s)
- Richard M. Stewart
- Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia
| | - Janice W. Y. Wong
- Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia
- Brain and Behaviour, Telethon Kids Institute, Perth, WA, Australia
- Specialised Child and Adolescent Mental Health Services, Department of Health, Perth, WA, Australia
| | - Simone Mahfouda
- Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia
- Brain and Behaviour, Telethon Kids Institute, Perth, WA, Australia
- School of Psychological Sciences, Faculty of Science, The University of Western Australia, Perth, WA, Australia
| | - Hugo A. E. Morandini
- Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia
| | - Pradeep Rao
- Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia
- Community Child and Adolescent Mental Health Services, Department of Health, Perth, WA, Australia
| | - Kevin C. Runions
- Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia
- Brain and Behaviour, Telethon Kids Institute, Perth, WA, Australia
- Community Child and Adolescent Mental Health Services, Department of Health, Perth, WA, Australia
| | - Florian D. Zepf
- Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia
- Brain and Behaviour, Telethon Kids Institute, Perth, WA, Australia
- Department of Child and Adolescent Psychiatry, Psychosomatic Medicine and Psychotherapy, Jena University Hospital, Friedrich Schiller University, Jena, Germany
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Chen X, Xu J, Tang J, Dai X, Huang H, Cao R, Hu J. Dysregulation of amino acids and lipids metabolism in schizophrenia with violence. BMC Psychiatry 2020; 20:97. [PMID: 32131778 PMCID: PMC7055102 DOI: 10.1186/s12888-020-02499-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 02/14/2020] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Many studies have related biochemical characteristics to violence and have reported schizophrenia could elevated the risk of violent behaviour. However, the metabolic characteristics of schizophrenia patients with violence (V.SC) are unclear. METHODS To explore the metabolic characteristics of schizophrenia with violence and to identify potential biomarkers, untargeted metabolomics was performed by using gas chromatography time-of-flight mass spectrometry to analyse the plasma metabolites of fifty-three V.SC and twenty-four schizophrenia patients without violence (NV.SC). Multivariate and univariate analyses were performed to identify differential metabolites and biomarkers. Violence was assessed by the MacArthur Violence Assessment Study method. Psychiatric symptoms were assessed by the Positive and Negative Syndrome Scale. RESULTS Multivariate analysis was unable to distinguish V.SC from NV.SC. Glycerolipid metabolism and phenylalanine, tyrosine and tryptophan biosynthesis were the differential metabolic pathways between V.SC and NV.SC. We confirmed ten metabolites and five metabolites as metabolic biomarkers of V.SC by random forest and support vector machine analysis, respectively. The biomarker panel, including the ratio of L-asparagine to L-aspartic acid, vanillylmandelic acid and glutaric acid, yielded an area under the receiver operating characteristic curve of 0.808. CONCLUSIONS This study gives a holistic view of the metabolic phenotype of schizophrenia with violence which is characterized by the dysregulation of lipids and amino acids. These results might provide information for the aetiological understanding and management of violence in schizophrenia; however, this is a preliminary metabolomics study about schizophrenia with violence, which needs to be repeated in future studies.
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Affiliation(s)
- Xiacan Chen
- grid.13291.380000 0001 0807 1581Institute of Forensic Medicine, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, China
| | - Jiajun Xu
- grid.13291.380000 0001 0807 1581Mental Health Center, West China Hospital, Sichuan University, Chengdu, China
| | - Jing Tang
- Chengdu Compulsory Medical Center, Chengdu, China
| | - Xinhua Dai
- grid.13291.380000 0001 0807 1581West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, 610041 China
| | - Haolan Huang
- grid.13291.380000 0001 0807 1581West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, 610041 China
| | - Ruochen Cao
- grid.13291.380000 0001 0807 1581West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, 610041 China
| | - Junmei Hu
- West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, 610041, China.
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Hildebrandt CS, Helmbold K, Linden M, Langen KJ, Filss CP, Runions KC, Stewart RM, Rao P, Moore JK, Mahfouda S, Morandini HAE, Wong JWY, Rink L, Zepf FD. No detectable effects of acute tryptophan depletion on short-term immune system cytokine levels in healthy adults. World J Biol Psychiatry 2019; 20:416-423. [PMID: 29353534 DOI: 10.1080/15622975.2018.1428357] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Objectives: Recent research suggested an influence of diminished central nervous serotonin (5-HT) synthesis on the leptin axis via immunological mechanisms in healthy adult females. However, studies assessing immunological parameters in combination with dietary challenge techniques that impact brain 5-HT synthesis in humans are lacking. Methods: In the present trial, a pilot analysis was conducted on data obtained in healthy adult humans receiving either different dietary acute tryptophan depletion (ATD) challenge or tryptophan (TRP)-balanced control conditions (BAL) to study the effects of reduced central nervous 5-HT synthesis on serum tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β) and IL-6 concentrations. The data of N = 35 healthy adults were analysed who were randomly subjected to one of the following two dietary conditions in a double-blind between-subject approach: (1) The Moja-De ATD challenge (ATD), or (2) TRP-balanced control condition for ATD Moja-De (BAL). Serum concentrations for the assessment of relevant parameters (TNF-α, IL-1β and IL-6) and relevant TRP-related characteristics after the respective challenge procedures were assessed at baseline (T0) and in hourly intervals after administration over a period of 6 h (T1-T6). Results: The ATD condition did not result in significant changes to cytokine concentrations for the entire study sample, or in male and female subgroups. Depletion of CNS 5-HT via dietary TRP depletion appears to have no statistically significant short-term impact on cytokine concentrations in healthy adults. Conclusions: Future research on immunological stressors in combination with challenge techniques will be of value in order to further disentangle the complex interplay between brain 5-HT synthesis and immunological pathways.
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Affiliation(s)
- Caroline S Hildebrandt
- a Jülich Aachen Research Alliance, JARA Translational Brain Medicine , Aachen , Germany.,b Clinic for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy , RWTH Aachen University , Aachen , Germany.,c Clinics of the City Cologne GmbH , Child and Adolescent Psychiatry and Psychotherapy , Cologne , Germany
| | - Katrin Helmbold
- a Jülich Aachen Research Alliance, JARA Translational Brain Medicine , Aachen , Germany.,b Clinic for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy , RWTH Aachen University , Aachen , Germany
| | - Maike Linden
- a Jülich Aachen Research Alliance, JARA Translational Brain Medicine , Aachen , Germany.,b Clinic for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy , RWTH Aachen University , Aachen , Germany
| | - Karl-Josef Langen
- d Institute of Neuroscience and Medicine (INM-4) Research Centre Jülich , Jülich , Germany.,e Section JARA-Brain , Jülich-Aachen Research Alliance (JARA) , Jülich , Germany.,f Department of Nuclear Medicine , RWTH Aachen University Hospital , Aachen , Germany
| | - C P Filss
- e Section JARA-Brain , Jülich-Aachen Research Alliance (JARA) , Jülich , Germany.,f Department of Nuclear Medicine , RWTH Aachen University Hospital , Aachen , Germany
| | - Kevin C Runions
- g Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy; School of Medicine, Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health , The University of Western Australia , Perth , Australia.,h Telethon Kids Institute , Perth , Australia
| | - Richard M Stewart
- g Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy; School of Medicine, Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health , The University of Western Australia , Perth , Australia
| | - Pradeep Rao
- g Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy; School of Medicine, Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health , The University of Western Australia , Perth , Australia.,i Department of Health , Community Child and Adolescent Mental Health Services (CAMHS) , Perth , Western Australia , Australia
| | - Julie K Moore
- g Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy; School of Medicine, Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health , The University of Western Australia , Perth , Australia.,j Princess Margaret Hospital, Department of Health , Pediatric Consultation Liason Program, Acute Child and Adolescent Mental Health Services (CAMHS) , Perth , Western Australia , Australia
| | - Simone Mahfouda
- g Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy; School of Medicine, Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health , The University of Western Australia , Perth , Australia.,h Telethon Kids Institute , Perth , Australia
| | - Hugo A E Morandini
- g Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy; School of Medicine, Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health , The University of Western Australia , Perth , Australia
| | - Janice W Y Wong
- g Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy; School of Medicine, Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health , The University of Western Australia , Perth , Australia.,h Telethon Kids Institute , Perth , Australia.,k Department of Health , Specialised Child and Adolescent Mental Health Services (CAMHS) , Perth , Western Australia , Australia
| | - Lothar Rink
- l Department of Immunology , RWTH Aachen University Hospital , Aachen , Germany
| | - Florian D Zepf
- a Jülich Aachen Research Alliance, JARA Translational Brain Medicine , Aachen , Germany.,b Clinic for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy , RWTH Aachen University , Aachen , Germany.,g Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy; School of Medicine, Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health , The University of Western Australia , Perth , Australia.,h Telethon Kids Institute , Perth , Australia.,k Department of Health , Specialised Child and Adolescent Mental Health Services (CAMHS) , Perth , Western Australia , Australia
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10
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Runions KC, Morandini HAE, Rao P, Wong JWY, Kolla NJ, Pace G, Mahfouda S, Hildebrandt CS, Stewart R, Zepf FD. Serotonin and aggressive behaviour in children and adolescents: a systematic review. Acta Psychiatr Scand 2019; 139:117-144. [PMID: 30446991 DOI: 10.1111/acps.12986] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/12/2018] [Indexed: 12/14/2022]
Abstract
OBJECTIVE The role of serotonin (5-HT) in human aggression has been the subject of a large number of studies, mostly with adults. Meta-analyses indicate a small but significant inverse relationship between central nervous 5-HT availability and aggression, but genetically informed studies suggest two pathways: one to reactive aggression and the other to proactive aggression. METHOD We conducted a systemic review on central nervous 5-HT function in children and adolescents, with attention to the function of aggression. RESULTS In total, 675 articles were screened for relevance, with 45 reviewed. These included blood assays (e.g. plasma, 5-HIAA; platelet 5-HTR2A ), epigenetic studies, retrospective PET studies and 5-HT challenge paradigms (e.g. tryptophan depletion). Overall, findings were mixed, with support both for negative and for positive associations of central nervous 5-HT function with aggression in children and adolescents. CONCLUSION We propose factors that may be blurring the picture, including problems in the conceptualization and measurement of aggression in young people, the lack of prospective designs and the bias towards clinical samples of boys. Research needs to account for variance in the both motivation for and implementation of aggression, and look to the behavioural economics literature to consider the roles of reward, vengeance and self-control more clearly.
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Affiliation(s)
- K C Runions
- Department of Health, Child and Adolescent Mental Health Services, Bentley, WA, Australia.,Telethon Kids Institute, University of Western Australia, Perth, WA, Australia.,Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health, Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, School of Medicine, University of Western Australia, Perth, WA, Australia
| | - H A E Morandini
- Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health, Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, School of Medicine, University of Western Australia, Perth, WA, Australia
| | - P Rao
- Department of Health, Child and Adolescent Mental Health Services, Bentley, WA, Australia.,Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health, Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, School of Medicine, University of Western Australia, Perth, WA, Australia
| | - J W Y Wong
- Department of Health, Child and Adolescent Mental Health Services, Bentley, WA, Australia.,Telethon Kids Institute, University of Western Australia, Perth, WA, Australia.,Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health, Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, School of Medicine, University of Western Australia, Perth, WA, Australia
| | - N J Kolla
- Centre for Addictions and Mental Health, University of Toronto, Toronto, ON, Canada
| | - G Pace
- Department of Health, Child and Adolescent Mental Health Services, Bentley, WA, Australia
| | - S Mahfouda
- Telethon Kids Institute, University of Western Australia, Perth, WA, Australia.,School of Psychological Sciences, Faculty of Sciences, University of Western Australia, Perth, WA, Australia
| | - C S Hildebrandt
- Jülich Aachen Research Alliance, JARA Translational Brain Medicine, Aachen, Germany.,Child and Adolescent Psychiatry and Psychotherapy, Clinics of the City Cologne GmbH, Cologne, Germany
| | - R Stewart
- Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health, Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, School of Medicine, University of Western Australia, Perth, WA, Australia
| | - F D Zepf
- Division of Psychiatry and Clinical Neurosciences and Division of Paediatrics and Child Health, Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, School of Medicine, University of Western Australia, Perth, WA, Australia.,Clinic for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Clinics of the Friedrich Schiller University, Jena, Germany
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11
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Biskup CS, Helmbold K, Baurmann D, Klasen M, Gaber TJ, Bubenzer-Busch S, Königschulte W, Fink GR, Zepf FD. Resting state default mode network connectivity in children and adolescents with ADHD after acute tryptophan depletion. Acta Psychiatr Scand 2016; 134:161-71. [PMID: 27145324 DOI: 10.1111/acps.12573] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/25/2016] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Alterations of the default mode network (DMN) have been described in patients with neuropsychiatric disorders, including attention deficit hyperactivity disorder (ADHD), and the neurotransmitter serotonin (5-HT) is known to modulate DMN activity. This study aimed to explore the role of 5-HT on the DMN and its functional connectivity (FC) in young patients with ADHD. METHODS Young male patients with ADHD (n = 12) and healthy controls (n = 10) (both aged 12-17 years) were subjected to acute tryptophan depletion (ATD) and subsequently diminished brain 5-HT synthesis. Three hours after challenge intake (ATD or a balanced control condition, BAL), resting state fMRI scans were obtained. RESULTS In patients, ATD led to attenuated FC of the right superior premotor cortex (BA 6) with the DMN, comparable to the extent found in controls after BAL administration. ATD lowered FC of the left somatosensory cortex (BA 3) with the DMN, independently of the factor group, but with stronger effects in controls. CONCLUSIONS Data reveal a serotonergic modulation of FC between BA 6 and 3, known to be relevant for motor planning and sensory perception, and the DMN, thereby possibly pointing toward ATD acting beneficially on neural planning of motor activity in patients with ADHD.
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Affiliation(s)
- C S Biskup
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany.,JARA Translational Brain Medicine, Aachen & Jülich, Germany.,Cognitive Neuroscience, Institute for Neuroscience and Medicine (INM3), Research Centre Jülich, Jülich, Germany
| | - K Helmbold
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany.,JARA Translational Brain Medicine, Aachen & Jülich, Germany
| | - D Baurmann
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany.,JARA Translational Brain Medicine, Aachen & Jülich, Germany.,Cognitive Neuroscience, Institute for Neuroscience and Medicine (INM3), Research Centre Jülich, Jülich, Germany
| | - M Klasen
- Department of Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany
| | - T J Gaber
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany.,JARA Translational Brain Medicine, Aachen & Jülich, Germany
| | - S Bubenzer-Busch
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany.,JARA Translational Brain Medicine, Aachen & Jülich, Germany.,Cognitive Neuroscience, Institute for Neuroscience and Medicine (INM3), Research Centre Jülich, Jülich, Germany
| | - W Königschulte
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany.,JARA Translational Brain Medicine, Aachen & Jülich, Germany.,Cognitive Neuroscience, Institute for Neuroscience and Medicine (INM3), Research Centre Jülich, Jülich, Germany
| | - G R Fink
- Cognitive Neuroscience, Institute for Neuroscience and Medicine (INM3), Research Centre Jülich, Jülich, Germany.,Department of Neurology, University of Cologne, Cologne, Germany
| | - F D Zepf
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany.,JARA Translational Brain Medicine, Aachen & Jülich, Germany.,Cognitive Neuroscience, Institute for Neuroscience and Medicine (INM3), Research Centre Jülich, Jülich, Germany.,Centre & Discipline of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy; School of Psychiatry and Clinical Neurosciences & School of Paediatrics and Child Health, Faculty of Medicine, Dentistry and Health Sciences, The University of Western Australia, Perth, WA, Australia.,Specialised Child and Adolescent Mental Health Services (CAMHS), Department of Health in Western Australia, Perth, WA, Australia
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12
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Hsiao CY, Tsai HC, Chi MH, Chen KC, Chen PS, Lee IH, Yeh TL, Yang YK. The Association between Baseline Subjective Anxiety Rating and Changes in Cardiac Autonomic Nervous Activity in Response to Tryptophan Depletion in Healthy Volunteers. Medicine (Baltimore) 2016; 95:e3498. [PMID: 27175645 PMCID: PMC4902487 DOI: 10.1097/md.0000000000003498] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The aim of this study was to investigate the influence of serotonin on anxiety and autonomic nervous system (ANS) function; the correlation between subjective anxiety rating and changes of ANS function following tryptophan depletion (TD) in healthy volunteers was examined. Twenty-eight healthy participants, consisting of 15 females and 13 males, with an average age of 33.3 years, were recruited.Baseline Chinese Symptom Checklist-90-Revised and ANS function measurements were taken. TD was carried out on the testing day, and participants provided blood samples right before and 5 hours after TD. ANS function, somatic symptoms, and Visual Analogue Scales (VASs) were determined after TD. Wilcoxon signed rank test and Spearman ρ correlation were adapted for analyses of the results.The TD procedure reduced total and free plasma tryptophan effectively. After TD, the sympathetic nervous activity increased and parasympathetic nervous activity decreased. Baseline anxiety ratings positively correlated with post-TD changes in sympathetic nervous activity, VAS ratings, and physical symptoms. However, a negative correlation with post-TD changes in parasympathetic nervous activity was found.The change in ANS function after TD was associated with the severity of anxiety in healthy volunteers. This supports the fact that the effect of anxiety on heart rate variability is related to serotonin vulnerability. Furthermore, it also shows that the subjective anxiety rating has a biological basis related to serotonin.
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Affiliation(s)
- Chih Yin Hsiao
- From the Department of Psychiatry, National Cheng Kung University Hospital (CYH, HCT, MHC, KCC, PSC, IHL, TLY, YKY), College of Medicine; Addiction Research Center (CYH, KCC, PSC, IHL, TLY, YKY), National Cheng Kung University, Tainan; Department of Psychiatry (HCT, KCC, YKY), National Cheng Kung University Hospital, Dou-Liou Branch, Yunlin; and Institute of Behavioral Medicine (YKY), College of Medicine, National Cheng Kung University, Tainan, Taiwan
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13
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Sánchez CL, Van Swearingen AED, Arrant AE, Biskup CS, Kuhn CM, Zepf FD. Simplified dietary acute tryptophan depletion: effects of a novel amino acid mixture on the neurochemistry of C57BL/6J mice. Food Nutr Res 2015; 59:27424. [PMID: 26278978 PMCID: PMC4538305 DOI: 10.3402/fnr.v59.27424] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 06/24/2015] [Accepted: 06/24/2015] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Diet and nutrition can impact on the biological processes underpinning neuropsychiatric disorders. Amino acid (AA) mixtures lacking a specific neurotransmitter precursor can change the levels of brain serotonin (5-HT) or dopamine (DA) in the central nervous system. The availability of these substances within the brain is determined by the blood-brain barrier (BBB) that restricts the access of peripheral AA into the brain. AA mixtures lacking tryptophan (TRP) compete with endogenous TRP for uptake into the brain across the BBB, which in turn leads to a decrease in central nervous 5-HT synthesis. OBJECTIVE The present study compared the effects of a simplified acute tryptophan depletion (SATD) mixture in mice on blood and brain serotonergic and dopaminergic metabolites to those of a commonly used acute tryptophan depletion mixture (ATD Moja-De) and its TRP-balanced control (BAL). DESIGN The SATD formula is composed of only three large neutral AAs: phenylalanine (PHE), leucine (LEU), and isoleucine (ILE). BAL, ATD Moja-De, or SATD formulas were delivered to adult male C57BL/6J mice by gavage. TRP, monoamines, and their metabolites were quantified in blood and brain regions (hippocampus, frontal cortex, amygdala, caudate putamen, and nucleus accumbens). RESULTS Both ATD Moja-De and SATD significantly decreased levels of serum and brain TRP, as well as brain 5-HIAA and 5-HT compared with BAL. SATD reduced HVA levels in caudate but did not alter total DA levels or DOPAC. SATD decreased TRP and serotonergic metabolites comparably to ATD Moja-De administration. CONCLUSION A simplified and more palatable combination of AAs can manipulate serotonergic function and might be useful to reveal underlying monoamine-related mechanisms contributing to different neuropsychiatric disorders.
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Affiliation(s)
- Cristina L Sánchez
- Clinic for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, JARA Brain, RWTH Aachen University, Aachen, Germany.,Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
| | | | - Andrew E Arrant
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
| | - Caroline S Biskup
- Clinic for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, JARA Brain, RWTH Aachen University, Aachen, Germany
| | - Cynthia M Kuhn
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
| | - Florian D Zepf
- Clinic for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, JARA Brain, RWTH Aachen University, Aachen, Germany.,Department of Child and Adolescent Psychiatry, School of Paediatrics and Child Health & School of Psychiatry and Clinical Neurosciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Western Australia, Perth, WA, Australia.,Specialised Child and Adolescent Mental Health Services (CAHMS), Department of Health, Perth, WA, Australia;
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14
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Biskup CS, Gaber T, Helmbold K, Bubenzer-Busch S, Zepf FD. Amino acid challenge and depletion techniques in human functional neuroimaging studies: an overview. Amino Acids 2015; 47:651-83. [DOI: 10.1007/s00726-015-1919-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 01/09/2015] [Indexed: 01/16/2023]
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15
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Does serotonin deficit mediate susceptibility to ADHD? Neurochem Int 2015; 82:52-68. [DOI: 10.1016/j.neuint.2015.02.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 01/18/2015] [Accepted: 02/07/2015] [Indexed: 11/21/2022]
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16
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Vicario CM. Aggression traits in youth psychopathy: the key role of serotonin. Front Psychiatry 2014; 5:25. [PMID: 24672490 PMCID: PMC3955848 DOI: 10.3389/fpsyt.2014.00025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 03/02/2014] [Indexed: 11/13/2022] Open
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