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Cizmecioglu A, Eryavuz Onmaz D, Senturk S, Askin D, Unlu A, Korkmaz H, Gungor G. Kynurenine Pathway Dysregulation and Pain Perception in Acute Pancreatitis: Has the Connection Unraveled? Neurosci Lett 2024; 837:137902. [PMID: 39029612 DOI: 10.1016/j.neulet.2024.137902] [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: 01/02/2024] [Revised: 07/11/2024] [Accepted: 07/15/2024] [Indexed: 07/21/2024]
Abstract
AIM Tryptophan (TRP), an essential amino acid, undergoes catabolism through various pathways. Notably, the kynurenine pathway (KP), constituting one of these pathways, exhibits a unidirectional impact on immune response and energy metabolism. Nonetheless, its influence on pain sensation is characterized by biphasic dynamics. This study aims to scrutinize the influence of the KP pathway on pain sensation, particularly within the context of pancreatic inflammation. METHODS Our prospective case-control study involved individuals diagnosed with acute pancreatitis and a control group matched for gender and age. The patient cohort was subsequently subdivided into severe and non-severe subgroups. To assess metabolites within KP, two blood samples were collected from the patient cohort, one at the time of diagnosis and another during the recovery phase. Furthermore, for pain quantification, daily pain scores utilizing the Visual Analog Scale (VAS) were extracted from the patients' medical records. RESULTS The study incorporated 30 patients along with an equivalent number of controls. A noticeable distinction was evident between the patient and control groups, characterized by an increase in kynurenine levels and a decrease in the tryptophan/kynurenine ratio. Throughout the process of disease recovery, a uniform decrease was observed in all KP metabolites, excluding 3-Hydroxykynurenine. Elevated levels of Kynurenic acid (KYNA) were correlated with increased pain scores. Critically, no apparent distinctions in KP metabolites were discerned concerning pain severity in patients with comorbidities characterized by neural involvement. CONCLUSION Based on our results, the kynurenine pathway (KP) is activated in instances of acute pancreatitis. Elevated levels of KYNA were found to be associated with heightened pain scores. The operative stages within the KP responsible for pain modulation are impaired in cases characterized by neuropathy-induced pain sensation.
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Affiliation(s)
- Ahmet Cizmecioglu
- Department of Internal Medicine, Faculty of Medicine, Selcuk University, Konya, Turkiye.
| | - Duygu Eryavuz Onmaz
- Department of Biochemistry, Faculty of Medicine, Selcuk University, Konya, Turkiye.
| | - Suleyman Senturk
- Division of Gastroenterology, Department of Internal Medicine, Faculty of Medicine, Selcuk University, Konya, Turkiye.
| | - Dudu Askin
- Department of Internal Medicine, Alanya Sifa Private Medical Center, Antalya, Turkiye.
| | - Ali Unlu
- Department of Biochemistry, Faculty of Medicine, Selcuk University, Konya, Turkiye.
| | - Huseyin Korkmaz
- Division of Gastroenterology, Department of Internal Medicine, Faculty of Medicine, Selcuk University, Konya, Turkiye.
| | - Gokhan Gungor
- Division of Gastroenterology, Department of Internal Medicine, Faculty of Medicine, Selcuk University, Konya, Turkiye.
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Colwell MJ, Tagomori H, Shang F, Cheng HI, Wigg CE, Browning M, Cowen PJ, Murphy SE, Harmer CJ. Direct serotonin release in humans shapes aversive learning and inhibition. Nat Commun 2024; 15:6617. [PMID: 39122687 PMCID: PMC11315928 DOI: 10.1038/s41467-024-50394-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 07/09/2024] [Indexed: 08/12/2024] Open
Abstract
The role of serotonin in human behaviour is informed by approaches which allow in vivo modification of synaptic serotonin. However, characterising the effects of increased serotonin signalling in human models of behaviour is challenging given the limitations of available experimental probes, notably selective serotonin reuptake inhibitors. Here we use a now-accessible approach to directly increase synaptic serotonin in humans (a selective serotonin releasing agent) and examine its influence on domains of behaviour historically considered core functions of serotonin. Computational techniques, including reinforcement learning and drift diffusion modelling, explain participant behaviour at baseline and after week-long intervention. Reinforcement learning models reveal that increasing synaptic serotonin reduces sensitivity for outcomes in aversive contexts. Furthermore, increasing synaptic serotonin enhances behavioural inhibition, and shifts bias towards impulse control during exposure to aversive emotional probes. These effects are seen in the context of overall improvements in memory for neutral verbal information. Our findings highlight the direct effects of increasing synaptic serotonin on human behaviour, underlining its role in guiding decision-making within aversive and more neutral contexts, and offering implications for longstanding theories of central serotonin function.
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Affiliation(s)
- Michael J Colwell
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK.
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK.
| | - Hosana Tagomori
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Fei Shang
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Hoi Iao Cheng
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Chloe E Wigg
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Michael Browning
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Philip J Cowen
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Susannah E Murphy
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK
| | - Catherine J Harmer
- University Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK.
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford, UK.
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Liu D, Hong Y, Chen Z, Ma Y, Xia S, Gu S, Zuo H. The Tryptophan Index Is Associated with Risk of Ischemic Stroke: A Community-Based Nested Case-Control Study. Nutrients 2024; 16:1544. [PMID: 38892478 PMCID: PMC11174068 DOI: 10.3390/nu16111544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Revised: 05/18/2024] [Accepted: 05/20/2024] [Indexed: 06/21/2024] Open
Abstract
BACKGROUND The relative availability of the essential amino acid tryptophan in the brain, as indicated by the tryptophan index, which is the ratio of tryptophan to its competing amino acids (CAAs) in circulation, has been related to major depression. However, it remains unknown whether tryptophan availability is involved in the pathogenesis of ischemic stroke. AIMS We aimed to investigate the relationship between the tryptophan index and the risk of ischemic stroke. METHODS We performed a nested case-control study within a community-based cohort in eastern China over the period 2013 to 2018. The analysis included 321 cases of ischemic stroke and 321 controls matched by sex and date of birth. The plasma levels of tryptophan and CAAs, including tyrosine, valine, phenylalanine, leucine, and isoleucine, were measured by ultra-high-performance liquid chromatography-tandem mass spectrometry. Conditional logistic regression analyses were employed to determine incidence rate ratios (IRRs) and their 95% confidence intervals (CIs). RESULTS After adjustment for body mass index, current smoking status, educational attainment, physical activity, family history of stroke, hypertension, diabetes, hyperlipidemia, and estimated glomerular filtration rate, an elevated tryptophan index was significantly associated with a reduced risk of ischemic stroke in a dose-response manner (IRR, 0.76; 95% CI, 0.63-0.93, per standard deviation increment). The plasma tryptophan or CAAs were not separately associated with the risk of ischemic stroke. CONCLUSIONS The tryptophan index was inversely associated with the risk of ischemic stroke. Our novel observations suggest that the availability of the essential amino acid tryptophan in the brain is involved in the pathogenesis of ischemic stroke.
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Affiliation(s)
- Dong Liu
- School of Public Health, Suzhou Medical College of Soochow University, 199 Ren’ai Rd., Suzhou 215123, China;
- School of Public Health, Nantong University, Nantong 226019, China;
| | - Yan Hong
- School of Public Health, Nantong University, Nantong 226019, China;
| | - Zhenting Chen
- Suzhou Medical College of Soochow University, Suzhou 215123, China; (Z.C.); (Y.M.); (S.X.)
| | - Yifan Ma
- Suzhou Medical College of Soochow University, Suzhou 215123, China; (Z.C.); (Y.M.); (S.X.)
| | - Shangyu Xia
- Suzhou Medical College of Soochow University, Suzhou 215123, China; (Z.C.); (Y.M.); (S.X.)
| | - Shujun Gu
- Department of Chronic Disease Control and Prevention, Changshu Center for Disease Control and Prevention, Suzhou 215501, China;
| | - Hui Zuo
- School of Public Health, Suzhou Medical College of Soochow University, 199 Ren’ai Rd., Suzhou 215123, China;
- Jiangsu Key Laboratory of Preventive and Translational Medicine for Major Chronic Non-Communicable Diseases, Suzhou Medical College of Soochow University, Suzhou 215123, China
- MOE Key Laboratory of Geriatric Diseases and Immunology, Suzhou Medical College of Soochow University, Suzhou 215123, China
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Ye J, Fan H, Shi R, Song G, Wu X, Wang D, Xia B, Zhao Z, Zhao B, Liu X, Wang Y, Dai X. Dietary lipoic acid alleviates autism-like behavior induced by acrylamide in adolescent mice: the potential involvement of the gut-brain axis. Food Funct 2024; 15:3395-3410. [PMID: 38465655 DOI: 10.1039/d3fo05078e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Consuming fried foods has been associated with an increased susceptibility to mental health disorders. Nevertheless, the impact of alpha-lipoic acid (α-LA, LA) on fried food-induced autism-like behavior remains unclear. This study aimed to explore how LA affects autism-related behavior and cognitive deficits caused by acrylamide in mice, a representative food hazard found in fried foods. This improvement was accomplished by enhanced synaptic plasticity, increased neurotrophin expression, elevated calcium-binding protein D28k, and restored serotonin. Additionally, LA substantially influenced the abundance of bacteria linked to autism and depression, simultaneously boosted short-chain fatty acid (SCFA) levels in fecal samples, and induced changes in serum amino acid concentrations. In summary, these findings suggested that exposure to acrylamide in adolescent mice could induce the development of social disorders in adulthood. LA showed promise as a nutritional intervention strategy to tackle emotional disorders during adolescence.
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Affiliation(s)
- Jin Ye
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China.
| | - Hua Fan
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China.
| | - Renjie Shi
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China.
| | - Ge Song
- BGI Institute of Applied Agriculture, BGI-Shenzhen, Shenzhen, China.
| | - Xiaoning Wu
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China.
| | - Danna Wang
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China.
| | - Bing Xia
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China.
| | - Zhenting Zhao
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China.
| | - Beita Zhao
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China.
| | - Xuebo Liu
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China.
| | - Yutang Wang
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China.
| | - Xiaoshuang Dai
- BGI Institute of Applied Agriculture, BGI-Shenzhen, Shenzhen, China.
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Dinu LM, Singh SN, Baker NS, Georgescu AL, Overton PG, Dommett EJ. The effects of tryptophan loading on Attention Deficit Hyperactivity in adults: A remote double blind randomised controlled trial. PLoS One 2023; 18:e0294911. [PMID: 38033150 PMCID: PMC10688902 DOI: 10.1371/journal.pone.0294911] [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: 08/23/2023] [Accepted: 11/03/2023] [Indexed: 12/02/2023] Open
Abstract
BACKGROUND Despite the impact and prevalence of Attention Deficit Hyperactivity Disorder (ADHD), current treatment options remain limited and there is a drive for alternative approaches, including those building on evidence of a role for tryptophan (TRP) and serotonin (5-HT). This study aimed to evaluate the effect of acute TRP loading on attention and impulsivity in adults with ADHD. TRIAL DESIGN AND METHODS We conducted a remote double blind randomised controlled trial (RCT) using TRP loading to examine the effects of a balanced amino acid load in comparison to low and high TRP loading in individuals with ADHD (medicated, N = 48, and unmedicated, N = 46) and controls (N = 50). Participants were randomised into one of three TRP treatment groups using stratified randomisation considering participant group and gender using a 1:1:1 ratio. Baseline testing of attention and impulsivity using the Test of Variables of Attention Task, Delay Discounting Task, and Iowa Gambling Task was followed by consumption of a protein drink (BAL, LOW, or HIGH TRP) before repeated testing. RESULTS AND CONCLUSIONS No effects of TRP were observed for any of the measures. In the present study, TRP loading did not impact on any measure of attention or impulsivity in those with ADHD or Controls. The findings need to be confirmed in another trial with a larger number of patients that also considers additional measures of dietary protein, plasma TRP and aggression. (Registration ID ISRCTN15119603).
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Affiliation(s)
- Larisa M. Dinu
- Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, United Kingdom
| | - Samriddhi N. Singh
- Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, United Kingdom
| | - Neo S. Baker
- Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, United Kingdom
| | - Alexandra L. Georgescu
- Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, United Kingdom
| | - Paul G. Overton
- Department of Psychology, The University of Sheffield, Cathedral Court, Sheffield, United Kingdom
| | - Eleanor J. Dommett
- Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, United Kingdom
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Balasubramanian R, Shutta KH, Guasch-Ferre M, Huang T, Jha SC, Zhu Y, Shadyab AH, Manson JE, Corella D, Fitó M, Hu FB, Rexrode KM, Clish CB, Hankinson SE, Kubzansky LD. Metabolomic profiles of chronic distress are associated with cardiovascular disease risk and inflammation-related risk factors. Brain Behav Immun 2023; 114:262-274. [PMID: 37557964 DOI: 10.1016/j.bbi.2023.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 08/01/2023] [Accepted: 08/06/2023] [Indexed: 08/11/2023] Open
Abstract
BACKGROUND Chronic psychological distress is associated with increased risk of cardiovascular disease (CVD) and investigators have posited inflammatory factors may be centrally involved in these relationships. However, mechanistic evidence and molecular underpinnings of these processes remain unclear, and data are particularly sparse among women. This study examined if a metabolite profile linked with distress was associated with increased CVD risk and inflammation-related risk factors. METHODS A plasma metabolite-based distress score (MDS) of twenty chronic psychological distress-related metabolites was developed in cross-sectional, 1:1 matched case-control data comprised of 558 women from the Nurses' Health Study (NHS; 279 women with distress, 279 controls). This MDS was then evaluated in two other cohorts: the Women's Health Initiative Observational Cohort (WHI-OS) and the Prevención con Dieta Mediterránea (PREDIMED) trial. We tested the MDS's association with risk of future CVD in each sample and with levels of C-reactive protein (CRP) in the WHI-OS. The WHI-OS subsample included 944 postmenopausal women (472 CHD cases; mean time to event = 5.8 years); the PREDIMED subsample included 980 men and women (224 CVD cases, mean time to event = 3.1 years). RESULTS In the WHI-OS, a 1-SD increase in the plasma MDS was associated with a 20% increased incident CHD risk (odds ratio [OR] = 1.20, 95% CI: 1.04 - 1.38), adjusting for known CVD risk factors excluding total and HDL cholesterol. This association was attenuated after including total and HDL cholesterol. CRP mediated an average 12.9% (95% CI: 4.9% - 28%, p < 10-15) of the total effect of MDS on CHD risk when adjusting for matching factors. This effect was attenuated after adjusting for known CVD risk factors. Of the metabolites in the MDS, tryptophan and threonine were inversely associated with incident CHD risk in univariate models. In PREDIMED, each one SD increase in the MDS was associated with an OR of 1.19 (95% CI: 1.00 - 1.41) for incident CVD risk, after adjusting all risk factors. Similar associations were observed in men and women. Four metabolites in the MDS were associated with incident CVD risk in PREDIMED in univariate models. Biliverdin and C36:5 phosphatidylcholine (PC) plasmalogen had inverse associations; C16:0 ceramide and C18:0 lysophosphatidylethanolamine(LPE) each had positive associations with CVD risk. CONCLUSIONS Our study points to molecular alterations that may underlie the association between chronic distress and subsequent risk of cardiovascular disease in adults.
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Affiliation(s)
- Raji Balasubramanian
- Department of Biostatistics and Epidemiology, University of Massachusetts Amherst, Amherst, MA, United States of America
| | - Katherine H Shutta
- Department of Biostatistics and Epidemiology, University of Massachusetts Amherst, Amherst, MA, United States of America; Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, United States of America; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Marta Guasch-Ferre
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, United States of America; Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, United States of America
| | - Tianyi Huang
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, United States of America; Harvard Medical School, Boston, MA, United States of America
| | - Shaili C Jha
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, United States of America
| | - Yiwen Zhu
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, United States of America
| | - Aladdin H Shadyab
- Herbert Wertheim School of Public Health and Human Longevity Science, University of California, San Diego, La Jolla, CA, United States of America
| | - JoAnn E Manson
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, United States of America; Harvard Medical School, Boston, MA, United States of America; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, United States of America; Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, MA, United States of America
| | - Dolores Corella
- Department of Preventive Medicine and Public Health. University of Valencia, Valencia Spain and CIBEROBN, Madrid, Spain
| | - Montserrat Fitó
- Epidemiology and Public Health program. Hospital del Mar Research Institute, Barcelona, Spain and CIBEROBN, Madrid, Spain
| | - Frank B Hu
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, United States of America; Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, United States of America; Harvard Medical School, Boston, MA, United States of America; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, United States of America
| | - Kathryn M Rexrode
- Harvard Medical School, Boston, MA, United States of America; Division of Women's Health, Department of Medicine, Brigham and Women's Hospital, Boston, MA, the United States of America
| | - Clary B Clish
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, United States of America
| | - Susan E Hankinson
- Department of Biostatistics and Epidemiology, University of Massachusetts Amherst, Amherst, MA, United States of America
| | - Laura D Kubzansky
- Department of Social and Behavioral Sciences, Harvard T.H. Chan School of Public Health, Boston, MA, United States of America
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Zhang L, Lu N, Liu M. Selective serotonin reuptake inhibitors regulate the interrelation between 5-HT and inflammation after myocardial infarction. BMC Cardiovasc Disord 2023; 23:342. [PMID: 37422634 PMCID: PMC10329792 DOI: 10.1186/s12872-023-03378-6] [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: 05/16/2023] [Accepted: 07/05/2023] [Indexed: 07/10/2023] Open
Abstract
BACKGROUND Acute myocardial infarction (AMI) is a main cause of death all around the world. There is a close relationship between myocardial infarction (MI) and depression. MI patients with untreated depression had higher mortality than those without depression. Therefore, this study aimed to explore the effect of escitalopram in treating a model under MI and unpredictable chronic mild stress (UCMS). METHODS Male C57BL/6J mice were treated with sham surgery, or MI surgery, or UCMS, or escitalopram (ES) for a consecutive two weeks. And the mice were divided into Sham group, MI group, MI + UCMS group, MI + UCMS + ES group (n = 8 in each group). After treatment, the mice went through open field test for anxiety behavior, sucrose preference test for depressive behavior. After sacrificed, the blood, heart, hippocampus, and cortex were collected. RESULTS The escitalopram badly increased the area of cardiac fibrosis size. The sucrose preference test demonstrated that escitalopram treatment showed significant effect in improving depressive behaviors of mice under MI + UCMS. The potential mechanism involved the interrelation between 5-HT system and inflammation. MI significantly affected the level of cardiac SERT. Both UCMS and ES significantly affected the level of cortex TNF-α. UCMS significantly affected the level of cardiac IL-33. In the hippocampus tissue, TNF-α was positively correlated with SERT, and IL-10 was positively correlated with SERT. In the cortex tissue, IL-33 was positively correlated with 5-HT4R, and sST2 was positively correlated with 5-HT. CONCLUSIONS Two-week escitalopram treatment might worsen myocardial infarction. But escitalopram could benefit depressive behaviors, which may be related with the interrelationship between the 5-HT system and inflammatory factors in the brain.
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Affiliation(s)
- Lijun Zhang
- Department of Psycho-cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, 100029, China
| | - Nan Lu
- Department of Psycho-cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, 100029, China
- Department of Cardiology, the First Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, 515041, China
| | - Meiyan Liu
- Department of Psycho-cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, 100029, China.
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Steding J, Ritschel F, Boehm I, Geisler D, King JA, Roessner V, Smolka MN, Zepf FD, Ehrlich S. The effects of acute tryptophan depletion on instrumental reward learning in anorexia nervosa - an fMRI study. Psychol Med 2023; 53:3426-3436. [PMID: 35343412 PMCID: PMC10277771 DOI: 10.1017/s0033291721005493] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 10/15/2021] [Accepted: 12/20/2021] [Indexed: 11/07/2022]
Abstract
BACKGROUND The serotonin (5-HT) hypothesis of anorexia nervosa (AN) posits that individuals predisposed toward or recovered from AN (recAN) have a central nervous hyperserotonergic state and therefore restrict food intake as a means to reduce 5-HT availability (via diminished tryptophan-derived precursor supply) and alleviate associated negative mood states. Importantly, the 5-HT system has also been generally implicated in reward processing, which has also been shown to be altered in AN. METHODS In this double-blind crossover study, 22 individuals recAN and 25 healthy control participants (HC) underwent functional magnetic resonance imaging (fMRI) while performing an established instrumental reward learning paradigm during acute tryptophan depletion (ATD; a dietary intervention that lowers central nervous 5-HT availability) as well as a sham depletion. RESULTS On a behavioral level, the main effects of reward and ATD were evident, but no group differences were found. fMRI analyses revealed a group × ATD × reward level interaction in the ventral anterior insula during reward anticipation as well as in the medial orbitofrontal cortex during reward consumption. DISCUSSION The precise pattern of results is suggestive of a 'normalization' of reward-related neural responses during ATD in recAN compared to HC. Our results lend further evidence to the 5-HT hypothesis of AN. Decreasing central nervous 5-HT synthesis and availability during ATD and possibly also by dieting may be a means to normalize 5-HT availability and associated brain processes.
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Affiliation(s)
- Julius Steding
- Translational Developmental Neuroscience Section, Division of Psychological and Social Medicine and Developmental Neurosciences, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - Franziska Ritschel
- Translational Developmental Neuroscience Section, Division of Psychological and Social Medicine and Developmental Neurosciences, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - Ilka Boehm
- Translational Developmental Neuroscience Section, Division of Psychological and Social Medicine and Developmental Neurosciences, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - Daniel Geisler
- Translational Developmental Neuroscience Section, Division of Psychological and Social Medicine and Developmental Neurosciences, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - Joseph A. King
- Translational Developmental Neuroscience Section, Division of Psychological and Social Medicine and Developmental Neurosciences, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - Veit Roessner
- Department of Child and Adolescent Psychiatry, Faculty of Medicine, University Hospital C. G. Carus, Technische Universität Dresden, Dresden, Germany
| | - Michael N. Smolka
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Florian Daniel Zepf
- Department of Child and Adolescent Psychiatry, Psychosomatic Medicine and Psychotherapy, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| | - Stefan Ehrlich
- Translational Developmental Neuroscience Section, Division of Psychological and Social Medicine and Developmental Neurosciences, Faculty of Medicine, TU Dresden, Dresden, Germany
- Eating Disorder Treatment and Research Center, Department of Child and Adolescent Psychiatry, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany
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9
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Li L, Tian Y. The role of metabolic reprogramming of tumor-associated macrophages in shaping the immunosuppressive tumor microenvironment. Biomed Pharmacother 2023; 161:114504. [PMID: 37002579 DOI: 10.1016/j.biopha.2023.114504] [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: 12/07/2022] [Revised: 03/04/2023] [Accepted: 03/07/2023] [Indexed: 03/15/2023] Open
Abstract
Macrophages are potent immune effector cells in innate immunity and exert dual-effects in the tumor microenvironment (TME). Tumor-associated macrophages (TAMs) make up a significant portion of TME immune cells. Similar to M1/M2 macrophages, TAMs are also highly plastic, and their functions are regulated by cytokines, chemokines and other factors in the TME. The metabolic changes in TAMs are significantly associated with polarization towards a protumour or antitumour phenotype. The metabolites generated via TAM metabolic reprogramming in turn promote tumor progression and immune tolerance. In this review, we explore the metabolic reprogramming of TAMs in terms of energy, amino acid and fatty acid metabolism and the potential roles of these changes in immune suppression.
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Affiliation(s)
- Lunxu Li
- Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, China
| | - Yu Tian
- Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, China.
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10
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Alberts C, Owe-Larsson M, Urbanska EM. New Perspective on Anorexia Nervosa: Tryptophan-Kynurenine Pathway Hypothesis. Nutrients 2023; 15:nu15041030. [PMID: 36839388 PMCID: PMC9967350 DOI: 10.3390/nu15041030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 02/14/2023] [Accepted: 02/16/2023] [Indexed: 02/22/2023] Open
Abstract
Anorexia nervosa (AN), affecting up to 4% of all females and 0.3% of all males globally, remains the neuropsychiatric disorder with the highest mortality rate. However, the response to the current therapeutic options is rarely satisfactory. Considering the devastating prognosis of survival among patients with AN, further research aimed at developing novel, more effective therapies for AN is essential. Brain and serum tryptophan is mostly converted along the kynurenine pathway into multiple neuroactive derivatives, whereas only 1-2% is used for the synthesis of serotonin. This narrative review provides an update on the experimental and clinical research data concerning the metabolism of tryptophan along the kynurenine pathway in anorexia nervosa based on the available literature. We propose that in AN, lower levels of L-kynurenine and kynurenic acid result in diminished stimulation of the aryl hydrocarbon receptor, which could contribute to abnormally low body weight. The impact of L-kynurenine supplementation on anorexia in animal models and the effects of changes in tryptophan and downstream kynurenines on the clinical progression of AN require further investigation. Moreover, prospective clinical studies on larger cohorts of restrictive and binge-eating/purging AN patients and assessing the potential benefit of L-kynurenine as an add-on therapeutic agent, should follow.
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Affiliation(s)
- Charl Alberts
- Department of Experimental and Clinical Pharmacology, Medical University of Lublin, Jaczewskiego 8B, 20-059 Lublin, Poland
| | - Maja Owe-Larsson
- Department of Histology and Embryology, Center of Biostructure Research, Medical University of Warsaw, Chałubińskiego 5, 02-004 Warsaw, Poland
- Laboratory of Center for Preclinical Research, Department of Experimental and Clinical Physiology, Medical University of Warsaw, Banacha 1B, 02-097 Warsaw, Poland
| | - Ewa M. Urbanska
- Laboratory of Cellular and Molecular Pharmacology, Department of Experimental and Clinical Pharmacology, Medical University of Lublin, Jaczewskiego 8B, 20-059 Lublin, Poland
- Correspondence:
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11
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Ayeni EA, Aldossary AM, Ayejoto DA, Gbadegesin LA, Alshehri AA, Alfassam HA, Afewerky HK, Almughem FA, Bello SM, Tawfik EA. Neurodegenerative Diseases: Implications of Environmental and Climatic Influences on Neurotransmitters and Neuronal Hormones Activities. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph191912495. [PMID: 36231792 PMCID: PMC9564880 DOI: 10.3390/ijerph191912495] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/21/2022] [Accepted: 09/24/2022] [Indexed: 05/23/2023]
Abstract
Neurodegenerative and neuronal-related diseases are major public health concerns. Human vulnerability to neurodegenerative diseases (NDDs) increases with age. Neuronal hormones and neurotransmitters are major determinant factors regulating brain structure and functions. The implications of environmental and climatic changes emerged recently as influence factors on numerous diseases. However, the complex interaction of neurotransmitters and neuronal hormones and their depletion under environmental and climatic influences on NDDs are not well established in the literature. In this review, we aim to explore the connection between the environmental and climatic factors to NDDs and to highlight the available and potential therapeutic interventions that could use to improve the quality of life and reduce susceptibility to NDDs.
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Affiliation(s)
- Emmanuel A. Ayeni
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ahmad M. Aldossary
- National Center of Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Science and Technology (KACST), Riyadh 12354, Saudi Arabia
| | - Daniel A. Ayejoto
- Department of Industrial Chemistry, University of Ilorin, Ilorin 240003, Nigeria
| | - Lanre A. Gbadegesin
- University of Chinese Academy of Sciences, Beijing 100049, China
- Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
| | - Abdullah A. Alshehri
- National Center of Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Science and Technology (KACST), Riyadh 12354, Saudi Arabia
| | - Haya A. Alfassam
- KACST-BWH Center of Excellence for Biomedicine, Joint Centers of Excellence Program, King Abdulaziz City for Science and Technology (KACST), Riyadh 12354, Saudi Arabia
| | - Henok K. Afewerky
- Department of Neurobiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430074, China
- School of Allied Health Professions, Asmara College of Health Sciences, Asmara P.O. Box 1220, Eritrea
| | - Fahad A. Almughem
- National Center of Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Science and Technology (KACST), Riyadh 12354, Saudi Arabia
| | - Saidu M. Bello
- Institute of Pharmacognosy, University of Szeged, 6720 Szeged, Hungary
| | - Essam A. Tawfik
- National Center of Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Science and Technology (KACST), Riyadh 12354, Saudi Arabia
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12
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Tanaka M, Szabó Á, Spekker E, Polyák H, Tóth F, Vécsei L. Mitochondrial Impairment: A Common Motif in Neuropsychiatric Presentation? The Link to the Tryptophan-Kynurenine Metabolic System. Cells 2022; 11:2607. [PMID: 36010683 PMCID: PMC9406499 DOI: 10.3390/cells11162607] [Citation(s) in RCA: 46] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/14/2022] [Accepted: 08/19/2022] [Indexed: 02/07/2023] Open
Abstract
Nearly half a century has passed since the discovery of cytoplasmic inheritance of human chloramphenicol resistance. The inheritance was then revealed to take place maternally by mitochondrial DNA (mtDNA). Later, a number of mutations in mtDNA were identified as a cause of severe inheritable metabolic diseases with neurological manifestation, and the impairment of mitochondrial functions has been probed in the pathogenesis of a wide range of illnesses including neurodegenerative diseases. Recently, a growing number of preclinical studies have revealed that animal behaviors are influenced by the impairment of mitochondrial functions and possibly by the loss of mitochondrial stress resilience. Indeed, as high as 54% of patients with one of the most common primary mitochondrial diseases, mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome, present psychiatric symptoms including cognitive impairment, mood disorder, anxiety, and psychosis. Mitochondria are multifunctional organelles which produce cellular energy and play a major role in other cellular functions including homeostasis, cellular signaling, and gene expression, among others. Mitochondrial functions are observed to be compromised and to become less resilient under continuous stress. Meanwhile, stress and inflammation have been linked to the activation of the tryptophan (Trp)-kynurenine (KYN) metabolic system, which observably contributes to the development of pathological conditions including neurological and psychiatric disorders. This review discusses the functions of mitochondria and the Trp-KYN system, the interaction of the Trp-KYN system with mitochondria, and the current understanding of the involvement of mitochondria and the Trp-KYN system in preclinical and clinical studies of major neurological and psychiatric diseases.
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Affiliation(s)
- Masaru Tanaka
- ELKH-SZTE Neuroscience Research Group, Danube Neuroscience Research Laboratory, Eötvös Loránd Research Network, University of Szeged (ELKH-SZTE), Tisza Lajos krt. 113, H-6725 Szeged, Hungary
| | - Ágnes Szabó
- Department of Neurology, Albert Szent-Györgyi Medical School, University of Szeged, Semmelweis u. 6, H-6725 Szeged, Hungary
- Doctoral School of Clinical Medicine, University of Szeged, Korányi fasor 6, H-6720 Szeged, Hungary
| | - Eleonóra Spekker
- ELKH-SZTE Neuroscience Research Group, Danube Neuroscience Research Laboratory, Eötvös Loránd Research Network, University of Szeged (ELKH-SZTE), Tisza Lajos krt. 113, H-6725 Szeged, Hungary
| | - Helga Polyák
- Department of Neurology, Albert Szent-Györgyi Medical School, University of Szeged, Semmelweis u. 6, H-6725 Szeged, Hungary
- Doctoral School of Clinical Medicine, University of Szeged, Korányi fasor 6, H-6720 Szeged, Hungary
| | - Fanni Tóth
- ELKH-SZTE Neuroscience Research Group, Danube Neuroscience Research Laboratory, Eötvös Loránd Research Network, University of Szeged (ELKH-SZTE), Tisza Lajos krt. 113, H-6725 Szeged, Hungary
| | - László Vécsei
- ELKH-SZTE Neuroscience Research Group, Danube Neuroscience Research Laboratory, Eötvös Loránd Research Network, University of Szeged (ELKH-SZTE), Tisza Lajos krt. 113, H-6725 Szeged, Hungary
- Department of Neurology, Albert Szent-Györgyi Medical School, University of Szeged, Semmelweis u. 6, H-6725 Szeged, Hungary
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13
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Michely J, Eldar E, Erdman A, Martin IM, Dolan RJ. Serotonin modulates asymmetric learning from reward and punishment in healthy human volunteers. Commun Biol 2022; 5:812. [PMID: 35962142 PMCID: PMC9374781 DOI: 10.1038/s42003-022-03690-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 07/08/2022] [Indexed: 11/15/2022] Open
Abstract
Instrumental learning is driven by a history of outcome success and failure. Here, we examined the impact of serotonin on learning from positive and negative outcomes. Healthy human volunteers were assessed twice, once after acute (single-dose), and once after prolonged (week-long) daily administration of the SSRI citalopram or placebo. Using computational modelling, we show that prolonged boosting of serotonin enhances learning from punishment and reduces learning from reward. This valence-dependent learning asymmetry increases subjects' tendency to avoid actions as a function of cumulative failure without leading to detrimental, or advantageous, outcomes. By contrast, no significant modulation of learning was observed following acute SSRI administration. However, differences between the effects of acute and prolonged administration were not significant. Overall, these findings may help explain how serotonergic agents impact on mood disorders.
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Affiliation(s)
- Jochen Michely
- Department of Psychiatry and Neurosciences, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Charité Clinician Scientist Program, Berlin, Germany.
- Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, UK.
- Wellcome Centre for Human Neuroimaging, University College London, London, UK.
| | - Eran Eldar
- Psychology and Cognitive Sciences Departments, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Alon Erdman
- Psychology and Cognitive Sciences Departments, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ingrid M Martin
- Wellcome Centre for Human Neuroimaging, University College London, London, UK
- Institute of Cognitive Neuroscience, University College London, London, UK
| | - Raymond J Dolan
- Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, UK
- Wellcome Centre for Human Neuroimaging, University College London, London, UK
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14
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Microbial-derived metabolites as a risk factor of age-related cognitive decline and dementia. Mol Neurodegener 2022; 17:43. [PMID: 35715821 PMCID: PMC9204954 DOI: 10.1186/s13024-022-00548-6] [Citation(s) in RCA: 67] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 05/30/2022] [Indexed: 02/06/2023] Open
Abstract
A consequence of our progressively ageing global population is the increasing prevalence of worldwide age-related cognitive decline and dementia. In the absence of effective therapeutic interventions, identifying risk factors associated with cognitive decline becomes increasingly vital. Novel perspectives suggest that a dynamic bidirectional communication system between the gut, its microbiome, and the central nervous system, commonly referred to as the microbiota-gut-brain axis, may be a contributing factor for cognitive health and disease. However, the exact mechanisms remain undefined. Microbial-derived metabolites produced in the gut can cross the intestinal epithelial barrier, enter systemic circulation and trigger physiological responses both directly and indirectly affecting the central nervous system and its functions. Dysregulation of this system (i.e., dysbiosis) can modulate cytotoxic metabolite production, promote neuroinflammation and negatively impact cognition. In this review, we explore critical connections between microbial-derived metabolites (secondary bile acids, trimethylamine-N-oxide (TMAO), tryptophan derivatives and others) and their influence upon cognitive function and neurodegenerative disorders, with a particular interest in their less-explored role as risk factors of cognitive decline.
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15
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Coray R, Quednow BB. The role of serotonin in declarative memory: A systematic review of animal and human research. Neurosci Biobehav Rev 2022; 139:104729. [PMID: 35691469 DOI: 10.1016/j.neubiorev.2022.104729] [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: 02/11/2022] [Revised: 05/13/2022] [Accepted: 06/06/2022] [Indexed: 10/18/2022]
Abstract
The serotonergic system is involved in diverse cognitive functions including memory. Of particular importance to daily life are declarative memories that contain information about personal experiences, general facts, and events. Several psychiatric or neurological diseases, such as depression, attention-deficit-hyperactivity disorder (ADHD), and dementia, show alterations in serotonergic signalling and attendant memory disorders. Nevertheless, understanding serotonergic neurotransmission and its influence on memory remained a challenge until today. In this systematic review, we summarize recent psychopharmacological studies in animals and humans from a psychological memory perspective, in consideration of task-specific requirements. This approach has the advantage that comparisons between serotonin (5-HT)-related neurochemical mechanisms and manipulations are each addressing specific mnemonic circuits. We conclude that applications of the same 5-HT-related treatments can differentially affect unrelated tasks of declarative memories. Moreover, the analysis of specific mnemonic phases (e.g., encoding vs. consolidation) reveals opposing impacts of increased or decreased 5-HT tones, with low 5-HT supporting spatial encoding but impairing the consolidation of objects and verbal memories. Promising targets for protein synthesis-dependent consolidation enhancements include 5-HT4 receptor agonists and 5-HT6 receptor antagonists, with the latter being of special interest for the treatment of age-related decline. Further implications are pointed out as base for the development of novel therapeutic targets for memory impairment of neuropsychiatric disorders.
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Affiliation(s)
- Rebecca Coray
- Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy, and Psychosomatics, Psychiatric University Hospital Zurich, University of Zurich, Switzerland; Neuroscience Center Zurich, University of Zurich and Swiss Federal Institute of Technology Zurich, Switzerland.
| | - Boris B Quednow
- Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy, and Psychosomatics, Psychiatric University Hospital Zurich, University of Zurich, Switzerland; Neuroscience Center Zurich, University of Zurich and Swiss Federal Institute of Technology Zurich, Switzerland
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16
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Wong NM, Dipasquale O, Turkheimer F, Findon JL, Wichers RH, Dimitrov M, Murphy CM, Stoencheva V, Robertson DM, Murphy DG, Daly E, McAlonan GM. Differences in social brain function in autism spectrum disorder are linked to the serotonin transporter: A randomised placebo-controlled single-dose crossover trial. J Psychopharmacol 2022; 36:723-731. [PMID: 35491679 DOI: 10.1177/02698811221092509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Alterations in the serotonergic control of brain pathways responsible for facial emotion processing in people with autism spectrum disorder (ASD) may be a target for intervention. However, the molecular underpinnings of autistic-neurotypical serotonergic differences are challenging to access in vivo. Receptor-Enriched Analysis of functional Connectivity by Targets (REACT) has helped define molecular-enriched functional magnetic resonance imaging (fMRI) brain networks based on a priori information about the spatial distribution of neurochemical systems from available PET templates. METHODS We used REACT to estimate the dominant fMRI signal related to the serotonin (5-HT) transporter (SERT) distribution during processing of aversive facial emotion in adults with and without ASD. We first predicted a group difference in baseline (placebo) functioning of this system. We next used a single 20 mg oral dose of citalopram, a serotonin reuptake inhibitor, to test the hypothesis that network activity in people with and without ASD would respond differently to inhibition of SERT. To confirm the specificity of our findings, we also repeated the analysis with 5-HT1A, 5-HT1B, 5-HT2A and 5-HT4 receptor maps. RESULTS Using REACT with the SERT map, we found a baseline group difference in the SERT-enriched response to faces in the ventromedial prefrontal cortex. A single oral dose of citalopram 'shifted' the response in the ASD group towards the neurotypical baseline but did not alter response in the control group. Similar differences in SERT-enriched response were observed after controlling for other 5-HT maps. CONCLUSIONS Our findings suggest that the SERT-enriched functional network is dynamically different in ASD during processing of socially relevant stimuli. Whether this acute neurobiological response to citalopram in ASD translates to a clinical target will be an important next step.
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Affiliation(s)
- Nichol Ml Wong
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,Sackler Institute for Translational Neurodevelopment, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,Biomedical Research Centre for Mental Health, Institute of Psychiatry, Psychology & Neuroscience, South London and Maudsley NHS Foundation Trust, UK.,Department of Psychology, The University of Hong Kong, Pokfulam, Hong Kong
| | - Ottavia Dipasquale
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Federico Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - James L Findon
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,Sackler Institute for Translational Neurodevelopment, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Robert H Wichers
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,Sackler Institute for Translational Neurodevelopment, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,Behavioural Genetics Clinic, Adult Autism and ADHD Service, Behavioural and Developmental Psychiatry Clinical Academic Group, South London and Maudsley NHS Foundation Trust, London, UK
| | - Mihail Dimitrov
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,Sackler Institute for Translational Neurodevelopment, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Clodagh M Murphy
- Behavioural Genetics Clinic, Adult Autism and ADHD Service, Behavioural and Developmental Psychiatry Clinical Academic Group, South London and Maudsley NHS Foundation Trust, London, UK
| | - Vladimira Stoencheva
- Behavioural Genetics Clinic, Adult Autism and ADHD Service, Behavioural and Developmental Psychiatry Clinical Academic Group, South London and Maudsley NHS Foundation Trust, London, UK
| | - Dene M Robertson
- Behavioural Genetics Clinic, Adult Autism and ADHD Service, Behavioural and Developmental Psychiatry Clinical Academic Group, South London and Maudsley NHS Foundation Trust, London, UK
| | - Declan G Murphy
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,Sackler Institute for Translational Neurodevelopment, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,Biomedical Research Centre for Mental Health, Institute of Psychiatry, Psychology & Neuroscience, South London and Maudsley NHS Foundation Trust, UK.,MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK
| | - Eileen Daly
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,Sackler Institute for Translational Neurodevelopment, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Grainne M McAlonan
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,Sackler Institute for Translational Neurodevelopment, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,Biomedical Research Centre for Mental Health, Institute of Psychiatry, Psychology & Neuroscience, South London and Maudsley NHS Foundation Trust, UK.,MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK
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17
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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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18
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Gilbert JR, Wusinich C, Zarate CA. A Predictive Coding Framework for Understanding Major Depression. Front Hum Neurosci 2022; 16:787495. [PMID: 35308621 PMCID: PMC8927302 DOI: 10.3389/fnhum.2022.787495] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 02/14/2022] [Indexed: 12/17/2022] Open
Abstract
Predictive coding models of brain processing propose that top-down cortical signals promote efficient neural signaling by carrying predictions about incoming sensory information. These "priors" serve to constrain bottom-up signal propagation where prediction errors are carried via feedforward mechanisms. Depression, traditionally viewed as a disorder characterized by negative cognitive biases, is associated with disrupted reward prediction error encoding and signaling. Accumulating evidence also suggests that depression is characterized by impaired local and long-range prediction signaling across multiple sensory domains. This review highlights the electrophysiological and neuroimaging evidence for disrupted predictive processing in depression. The discussion is framed around the manner in which disrupted generative predictions about the sensorium could lead to depressive symptomatology, including anhedonia and negative bias. In particular, the review focuses on studies of sensory deviance detection and reward processing, highlighting research evidence for both disrupted generative predictions and prediction error signaling in depression. The role of the monoaminergic and glutamatergic systems in predictive coding processes is also discussed. This review provides a novel framework for understanding depression using predictive coding principles and establishes a foundational roadmap for potential future research.
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Affiliation(s)
- Jessica R. Gilbert
- Experimental Therapeutics and Pathophysiology Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States
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19
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Zhang ZW, Gao CS, Zhang H, Yang J, Wang YP, Pan LB, Yu H, He CY, Luo HB, Zhao ZX, Zhou XB, Wang YL, Fu J, Han P, Dong YH, Wang G, Li S, Wang Y, Jiang JD, Zhong W. Morinda officinalis oligosaccharides increase serotonin in the brain and ameliorate depression via promoting 5-hydroxytryptophan production in the gut microbiota. Acta Pharm Sin B 2022; 12:3298-3312. [PMID: 35967282 PMCID: PMC9366226 DOI: 10.1016/j.apsb.2022.02.032] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/23/2022] [Accepted: 02/22/2022] [Indexed: 01/01/2023] Open
Affiliation(s)
- Zheng-Wei Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Chun-Sheng Gao
- Beijing Institute of Pharmacology and Toxicology, Beijing 100000, China
| | - Heng Zhang
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Jian Yang
- The National Clinical Research Center for Mental Disorders & Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing 100088, China
- Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing 100069, China
| | - Ya-Ping Wang
- The National Clinical Research Center for Mental Disorders & Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing 100088, China
- Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing 100069, China
| | - Li-Bin Pan
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Hang Yu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Chi-Yu He
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Hai-Bin Luo
- School of Pharmaceutical Sciences, Hainan University, Hainan 570228, China
| | - Zhen-Xiong Zhao
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Xin-Bo Zhou
- National Engineering Research Center for the Emergence Drugs, Beijing 100000, China
| | - Yu-Li Wang
- Beijing Institute of Pharmacology and Toxicology, Beijing 100000, China
| | - Jie Fu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Pei Han
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Yu-Hui Dong
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Gang Wang
- The National Clinical Research Center for Mental Disorders & Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing 100088, China
- Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing 100069, China
| | - Song Li
- School of Pharmaceutical Sciences, Hainan University, Hainan 570228, China
- Corresponding authors.
| | - Yan Wang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
- Corresponding authors.
| | - Jian-Dong Jiang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
- Corresponding authors.
| | - Wu Zhong
- National Engineering Research Center for the Emergence Drugs, Beijing 100000, China
- Corresponding authors.
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20
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Yee DM, Leng X, Shenhav A, Braver TS. Aversive motivation and cognitive control. Neurosci Biobehav Rev 2022; 133:104493. [PMID: 34910931 PMCID: PMC8792354 DOI: 10.1016/j.neubiorev.2021.12.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 11/12/2021] [Accepted: 12/09/2021] [Indexed: 02/03/2023]
Abstract
Aversive motivation plays a prominent role in driving individuals to exert cognitive control. However, the complexity of behavioral responses attributed to aversive incentives creates significant challenges for developing a clear understanding of the neural mechanisms of this motivation-control interaction. We review the animal learning, systems neuroscience, and computational literatures to highlight the importance of experimental paradigms that incorporate both motivational context manipulations and mixed motivational components (e.g., bundling of appetitive and aversive incentives). Specifically, we postulate that to understand aversive incentive effects on cognitive control allocation, a critical contextual factor is whether such incentives are associated with negative reinforcement or punishment. We further illustrate how the inclusion of mixed motivational components in experimental paradigms enables increased precision in the measurement of aversive influences on cognitive control. A sharpened experimental and theoretical focus regarding the manipulation and assessment of distinct motivational dimensions promises to advance understanding of the neural, monoaminergic, and computational mechanisms that underlie the interaction of motivation and cognitive control.
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Affiliation(s)
- Debbie M Yee
- Cognitive, Linguistic, and Psychological Sciences, Brown University, USA; Carney Institute for Brain Science, Brown University, USA; Department of Psychological and Brain Sciences, Washington University in Saint Louis, USA.
| | - Xiamin Leng
- Cognitive, Linguistic, and Psychological Sciences, Brown University, USA; Carney Institute for Brain Science, Brown University, USA
| | - Amitai Shenhav
- Cognitive, Linguistic, and Psychological Sciences, Brown University, USA; Carney Institute for Brain Science, Brown University, USA
| | - Todd S Braver
- Department of Psychological and Brain Sciences, Washington University in Saint Louis, USA
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21
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Escitalopram modulates learning content-specific neuroplasticity of functional brain networks. Neuroimage 2021; 247:118829. [PMID: 34923134 DOI: 10.1016/j.neuroimage.2021.118829] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 12/09/2021] [Accepted: 12/15/2021] [Indexed: 01/09/2023] Open
Abstract
Learning-induced neuroplastic changes, further modulated by content and setting, are mirrored in brain functional connectivity (FC). In animal models, selective serotonin reuptake inhibitors (SSRIs) have been shown to facilitate neuroplasticity. This is especially prominent during emotional relearning, such as fear extinction, which may translate to clinical improvements in patients. To investigate a comparable modulation of neuroplasticity in humans, 99 healthy subjects underwent three weeks of emotional (matching faces) or non-emotional learning (matching Chinese characters to unrelated German nouns). Shuffled pairings of the original content were subsequently relearned for the same time. During relearning, subjects received either a daily dose of the SSRI escitalopram or placebo. Resting-state functional magnetic resonance imaging was performed before and after the (re-)learning phases. FC changes in a network comprising Broca's area, the medial prefrontal cortex, the right inferior temporal and left lingual gyrus were modulated by escitalopram intake. More specifically, it increased the bidirectional connectivity between medial prefrontal cortex and lingual gyrus for non-emotional and the connectivity from medial prefrontal cortex to Broca's area for emotional relearning. The context dependence of these effects together with behavioral correlations supports the assumption that SSRIs in clinical practice improve neuroplasticity rather than psychiatric symptoms per se. Beyond expanding the complexities of learning, these findings emphasize the influence of external factors on human neuroplasticity.
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22
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Sen A. Does serotonin deficiency lead to anosmia, ageusia, dysfunctional chemesthesis and increased severity of illness in COVID-19? Med Hypotheses 2021; 153:110627. [PMID: 34139598 PMCID: PMC8180092 DOI: 10.1016/j.mehy.2021.110627] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 05/24/2021] [Accepted: 06/04/2021] [Indexed: 12/20/2022]
Abstract
Different mechanisms forwarded to understand anosmia and ageusia in coronavirus patients are not adequate to explain reversible anosmia and ageusia, which are resolved quickly. In addition, the reason behind the impaired chemesthetic sensations in some coronavirus patients remains unknown. In the present paper it is proposed that SARS-CoV-2 patients suffer from depletion of tryptophan, as ACE2, a key element in the process of absorption of tryptophan from the food, is significantly reduced in the patients as coronavirus uses ACE2 as the receptor to enter the host cells. The tryptophan depletion leads to a deficit of serotonin (5-HT) in SARS-COV-2 patients because tryptophan is the precursor in the synthesis of 5-HT. Such 5-HT deficiency can explain anosmia, ageusia and dysfunctional chemesthesis in COVID-19, given the fact that 5-HT is an important neuromodulator in the olfactory neurons, taste receptor cells and transient receptor potential channels (TRP channels) involved in chemesthesis. In addition, 5-HT deficiency worsens silent hypoxemia and depresses hypoxic pulmonary vasoconstriction leading to increased severity of the disease. Also, the levels of anti-inflammatory melatonin (synthesized from 5-HT) and nicotinamide adenine dinucleotide (NAD+, produced from niacin whose precursor is the tryptophan) might decrease in coronavirus patients resulting in the aggravation of the disease. Interestingly, selective serotonin reuptake inhibitors (SSRIs) may not be of much help in correcting the 5-HT deficiency in COVID-19 patients, as their efficacy goes down significantly when there is depletion of tryptophan in the system. Hence, tryptophan supplementation may herald a radical change in the treatment of COVID-19 and accordingly, clinical trials (therapeutic / prophylactic) should be conducted on coronavirus patients to find out how tryptophan supplementation (oral or parenteral, the latter in severe cases where there is hardly any absorption of tryptophan from the food) helps in curing, relieving or preventing the olfactory, gustatory and chemesthetic dysfunctions and in lessening the severity of the disease.
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Affiliation(s)
- Amarnath Sen
- 40 Jadunath Sarbovouma Lane, Kolkata 700035, India.
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23
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Liu L, Artigas SO, Ulrich A, Tardu J, Mohr PNC, Wilms B, Koletzko B, Schmid SM, Park SQ. Eating to dare - Nutrition impacts human risky decision and related brain function. Neuroimage 2021; 233:117951. [PMID: 33722669 DOI: 10.1016/j.neuroimage.2021.117951] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 03/02/2021] [Accepted: 03/06/2021] [Indexed: 10/21/2022] Open
Abstract
Macronutrient composition modulates plasma amino acids that are precursors of neurotransmitters and can impact brain function and decisions. Neurotransmitter serotonin has been shown to regulate not only food intake, but also economic decisions. We investigated whether an acute nutrition-manipulation inducing plasma tryptophan fluctuation affects brain function, thereby affecting risky decisions. Breakfasts differing in carbohydrate/protein ratios were offered to test changes in risky decision-making while metabolic and neural dynamics were tracked. We identified that a high-carbohydrate/protein breakfast increased plasma tryptophan/LNAA (large neutral amino acids) ratio which mapped to individual risk propensity changes. The nutrition-manipulation and tryptophan/LNAA fluctuation effects on risk propensity changes were further modulated by individual differences in body fat mass. Using fMRI, we further identified activation in the parietal lobule during risk-processing, of which activities 1) were sensitive to the tryptophan/LNAA fluctuation, 2) were modulated by individual's body fat mass, and 3) predicted the risk propensity changes in decision-making. Our results provide evidence for a personalized nutrition-driven modulation on human risky decision and its metabolic and neural mechanisms.
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Affiliation(s)
- Lu Liu
- Department of Decision Neuroscience & Nutrition, German Institute of Human Nutrition (DIfE), Nuthetal, Germany; Department of Psychology, University of Lübeck, Lübeck, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany.
| | | | - Anja Ulrich
- Institute for Endocrinology & Diabetes, University of Lübeck, Lübeck, Germany
| | - Jeremy Tardu
- Institute for Endocrinology & Diabetes, University of Lübeck, Lübeck, Germany
| | - Peter N C Mohr
- School of Business and Economics, Freie Universität Berlin, Germany; WZB Berlin Social Science Center, Berlin, Germany; Center for Cognitive Neuroscience Berlin, Freie Universität Berlin, Berlin, Germany
| | - Britta Wilms
- German Center for Diabetes Research (DZD), Neuherberg, Germany; Institute for Endocrinology & Diabetes, University of Lübeck, Lübeck, Germany
| | - Berthold Koletzko
- Dr. von Hauner Children's Hospital, University of Munich Medical Center, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Sebastian M Schmid
- German Center for Diabetes Research (DZD), Neuherberg, Germany; Institute for Endocrinology & Diabetes, University of Lübeck, Lübeck, Germany
| | - Soyoung Q Park
- Department of Decision Neuroscience & Nutrition, German Institute of Human Nutrition (DIfE), Nuthetal, Germany; Department of Psychology, University of Lübeck, Lübeck, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany; Neuroscience Research Center, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Neuroscience Research Center, Berlin, Germany.
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24
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Serotonin deficiency induced after brain maturation rescues consequences of early life adversity. Sci Rep 2021; 11:5368. [PMID: 33686115 PMCID: PMC7940624 DOI: 10.1038/s41598-021-83592-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 01/22/2021] [Indexed: 01/31/2023] Open
Abstract
Brain serotonin (5-HT) system dysfunction is implicated in depressive disorders and acute depletion of 5-HT precursor tryptophan has frequently been used to model the influence of 5-HT deficiency on emotion regulation. Tamoxifen (TAM)-induced Cre/loxP-mediated inactivation of the tryptophan hydroxylase-2 gene (Tph2) was used to investigate the effects of provoked 5-HT deficiency in adult mice (Tph2 icKO) previously subjected to maternal separation (MS). The efficiency of Tph2 inactivation was validated by immunohistochemistry and HPLC. The impact of Tph2 icKO in interaction with MS stress (Tph2 icKO × MS) on physiological parameters, emotional behavior and expression of 5-HT system-related marker genes were assessed. Tph2 icKO mice displayed a significant reduction in 5-HT immunoreactive cells and 5-HT concentrations in the rostral raphe region within four weeks following TAM treatment. Tph2 icKO and MS differentially affected food and water intake, locomotor activity as well as panic-like escape behavior. Tph2 icKO prevented the adverse effects of MS stress and altered the expression of the genes previously linked to stress and emotionality. In conclusion, an experimental model was established to study the behavioral and neurobiological consequences of 5-HT deficiency in adulthood in interaction with early-life adversity potentially affecting brain development and the pathogenesis of depressive disorders.
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25
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Effects of tryptophan depletion on anxiety, a systematic review. Transl Psychiatry 2021; 11:118. [PMID: 33574223 PMCID: PMC7878770 DOI: 10.1038/s41398-021-01219-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 10/30/2020] [Accepted: 11/16/2020] [Indexed: 12/11/2022] Open
Abstract
Vulnerability markers for onset of anxiety disorders are scarce. In depression, patients at risk tend to respond with a negative mood to 'acute tryptophan depletion' (ATD), while healthy volunteers and current patients do not. The serotonergic system thus provides indications for vulnerability for depression. It is unknown whether ATD reveals vulnerability in anxiety too. This study systematically reviews the effects of ATD on anxiety and assesses whether challenging anxiety modifies the response. PubMed, Embase and PsychInfo were systematically searched up to April 2019 for studies in which (1) healthy volunteers or patients with a (remitted) anxiety disorder underwent ATD and (2) levels of anxiety were reported. In total, 21 studies were included. Studies conducted in healthy volunteers (n = 13), and patients with a remitted (n = 6) or current (panic, social or generalised) anxiety disorder (n = 4). Studies were mostly of poor quality and heterogeneous regarding population, challenge test used and outcome measures. ATD did not consistently affect anxiety in any of the groups. Moreover, a challenge test after ATD (n = 17 studies) did not consistently provoke anxiety in healthy volunteers or remitted patients. A 35% CO2 challenge did consistently increase anxiety in patients with a current panic disorder (PD). To conclude, this systematic review found no clear indications that ATD provokes anxiety in those at risk for anxiety disorders. Hence, unlike in depression, ATD does not indicate vulnerability to develop an anxiety disorder. Because included studies were heterogeneous and mostly of poor quality, there is an urgent need for high quality research in homogeneous samples.
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26
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Kanen JW, Arntz FE, Yellowlees R, Cardinal RN, Price A, Christmas DM, Apergis-Schoute AM, Sahakian BJ, Robbins TW. Serotonin depletion amplifies distinct human social emotions as a function of individual differences in personality. Transl Psychiatry 2021; 11:81. [PMID: 33518708 PMCID: PMC7847998 DOI: 10.1038/s41398-020-00880-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 05/28/2020] [Accepted: 05/29/2020] [Indexed: 01/08/2023] Open
Abstract
Serotonin is involved in a wide range of mental capacities essential for navigating the social world, including emotion and impulse control. Much recent work on serotonin and social functioning has focused on decision-making. Here we investigated the influence of serotonin on human emotional reactions to social conflict. We used a novel computerised task that required mentally simulating social situations involving unjust harm and found that depleting the serotonin precursor tryptophan-in a double-blind randomised placebo-controlled design-enhanced emotional responses to the scenarios in a large sample of healthy volunteers (n = 73), and interacted with individual differences in trait personality to produce distinctive human emotions. Whereas guilt was preferentially elevated in highly empathic participants, annoyance was potentiated in those high in trait psychopathy, with medium to large effect sizes. Our findings show how individual differences in personality, when combined with fluctuations of serotonin, may produce diverse emotional phenotypes. This has implications for understanding vulnerability to psychopathology, determining who may be more sensitive to serotonin-modulating treatments, and casts new light on the functions of serotonin in emotional processing.
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Affiliation(s)
- Jonathan W Kanen
- Department of Psychology, University of Cambridge, Cambridge, UK.
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK.
| | - Fréderique E Arntz
- Department of Psychology, University of Cambridge, Cambridge, UK
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Department of Psychology, Leiden University, Leiden, The Netherlands
| | - Robyn Yellowlees
- Department of Psychology, University of Cambridge, Cambridge, UK
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Section of Eating Disorders, Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Rudolf N Cardinal
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Department of Psychiatry, University of Cambridge, Cambridge, UK
- Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
| | - Annabel Price
- Department of Psychiatry, University of Cambridge, Cambridge, UK
- Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
| | - David M Christmas
- Department of Psychiatry, University of Cambridge, Cambridge, UK
- Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
| | - Annemieke M Apergis-Schoute
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Department of Neuroscience, Psychology, and Behaviour, University of Leicester, Leicester, UK
| | - Barbara J Sahakian
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Department of Psychiatry, University of Cambridge, Cambridge, UK
| | - Trevor W Robbins
- Department of Psychology, University of Cambridge, Cambridge, UK
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
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27
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Kanen JW, Arntz FE, Yellowlees R, Christmas DM, Price A, Apergis-Schoute AM, Sahakian BJ, Cardinal RN, Robbins TW. Effect of Tryptophan Depletion on Conditioned Threat Memory Expression: Role of Intolerance of Uncertainty. BIOLOGICAL PSYCHIATRY: COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2021; 6:590-598. [PMID: 33631385 PMCID: PMC8099731 DOI: 10.1016/j.bpsc.2020.12.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 12/02/2022]
Abstract
Background Responding emotionally to danger is critical for survival. Normal functioning also requires flexible alteration of emotional responses when a threat becomes safe. Aberrant threat and safety learning occur in many psychiatric disorders, including posttraumatic stress disorder, obsessive-compulsive disorder, and schizophrenia, in which emotional responses can persist pathologically. While there is evidence that threat and safety learning can be modulated by the serotonin systems, there have been few studies in humans. We addressed a critical clinically relevant question: How does lowering serotonin affect memory retention of conditioned threat and safety memory? Methods Forty-seven healthy participants underwent conditioning to two stimuli predictive of threat on day 1. One stimulus but not the other was subsequently presented in an extinction session. Emotional responding was assessed by the skin conductance response. On day 2, we employed acute dietary tryptophan depletion to lower serotonin temporarily, in a double-blind, placebo-controlled, randomized between-groups design. We then tested for the retention of conditioned threat and extinction memory. We also measured self-reported intolerance of uncertainty, known to modulate threat memory expression. Results The expression of emotional memory was attenuated in participants who had undergone tryptophan depletion. Individuals who were more intolerant of uncertainty showed even greater attenuation of emotion following depletion. Conclusions These results support the view that serotonin is involved in predicting aversive outcomes and refine our understanding of the role of serotonin in the persistence of emotional responsivity, with implications for individual differences in vulnerability to psychopathology.
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Affiliation(s)
- Jonathan W Kanen
- Department of Psychology, University of Cambridge, Cambridge, United Kingdom; Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, United Kingdom.
| | - Frederique E Arntz
- Department of Psychology, University of Cambridge, Cambridge, United Kingdom; Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, United Kingdom; Department of Psychology, Leiden University, Leiden, the Netherlands
| | - Robyn Yellowlees
- Department of Psychology, University of Cambridge, Cambridge, United Kingdom; Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, United Kingdom; Section of Eating Disorders, Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - David M Christmas
- Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom; Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, United Kingdom
| | - Annabel Price
- Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom; Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, United Kingdom
| | - Annemieke M Apergis-Schoute
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, United Kingdom; Department of Neuroscience, Psychology and Behaviour, University of Leicester, Leicester, United Kingdom
| | - Barbara J Sahakian
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, United Kingdom; Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom
| | - Rudolf N Cardinal
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, United Kingdom; Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom; Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, United Kingdom
| | - Trevor W Robbins
- Department of Psychology, University of Cambridge, Cambridge, United Kingdom; Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, United Kingdom
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28
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Serotonin depletion impairs both Pavlovian and instrumental reversal learning in healthy humans. Mol Psychiatry 2021; 26:7200-7210. [PMID: 34429517 PMCID: PMC8873011 DOI: 10.1038/s41380-021-01240-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 07/03/2021] [Accepted: 07/09/2021] [Indexed: 02/07/2023]
Abstract
Serotonin is involved in updating responses to changing environmental circumstances. Optimising behaviour to maximise reward and minimise punishment may require shifting strategies upon encountering new situations. Likewise, autonomic responses to threats are critical for survival yet must be modified as danger shifts from one source to another. Whilst numerous psychiatric disorders are characterised by behavioural and autonomic inflexibility, few studies have examined the contribution of serotonin in humans. We modelled both processes, respectively, in two independent experiments (N = 97). Experiment 1 assessed instrumental (stimulus-response-outcome) reversal learning whereby individuals learned through trial and error which action was most optimal for obtaining reward or avoiding punishment initially, and the contingencies subsequently reversed serially. Experiment 2 examined Pavlovian (stimulus-outcome) reversal learning assessed by the skin conductance response: one innately threatening stimulus predicted receipt of an uncomfortable electric shock and another did not; these contingencies swapped in a reversal phase. Upon depleting the serotonin precursor tryptophan-in a double-blind randomised placebo-controlled design-healthy volunteers showed impairments in updating both actions and autonomic responses to reflect changing contingencies. Reversal deficits in each domain, furthermore, were correlated with the extent of tryptophan depletion. Initial Pavlovian conditioning, moreover, which involved innately threatening stimuli, was potentiated by depletion. These results translate findings in experimental animals to humans and have implications for the neurochemical basis of cognitive inflexibility.
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29
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Aquili L. The Role of Tryptophan and Tyrosine in Executive Function and Reward Processing. Int J Tryptophan Res 2020; 13:1178646920964825. [PMID: 33149600 PMCID: PMC7586026 DOI: 10.1177/1178646920964825] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 09/10/2020] [Indexed: 01/31/2023] Open
Abstract
The serotonergic precursor tryptophan and the dopaminergic precursor tyrosine have been shown to be important modulators of mood, behaviour and cognition. Specifically, research on the function of tryptophan has characterised this molecule as particularly relevant in the context of pathological disorders such as depression. Moreover, a large body of evidence has now been accumulated to suggest that tryptophan may also be involved in executive function and reward processing. Despite some clear differentiation with tryptophan, the data reviewed in this paper illustrates that tyrosine shares similar functions with tryptophan in the regulation of executive function and reward, and that these processes in turn, rather than acting in isolation, causally influence each other.
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Affiliation(s)
- Luca Aquili
- College of Health & Human Sciences, Charles Darwin University, Darwin, Northern Territory, Australia
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30
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Baldassarri SR, Park E, Finnema SJ, Planeta B, Nabulsi N, Najafzadeh S, Ropchan J, Huang Y, Hannestad J, Maloney K, Bhagwagar Z, Carson RE. Inverse changes in raphe and cortical 5-HT 1B receptor availability after acute tryptophan depletion in healthy human subjects. Synapse 2020; 74:e22159. [PMID: 32324935 DOI: 10.1002/syn.22159] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 04/08/2020] [Accepted: 04/19/2020] [Indexed: 11/07/2022]
Abstract
Serotonergic neurotransmission plays a key role in the pathophysiology and treatment of various neuropsychiatric diseases. The purpose of this study was to investigate changes in serotonergic neurotransmission after acute tryptophan depletion (ATD) using positron emission tomography (PET) with [11 C]P943, a 5-HT1B receptor radioligand previously shown to be sensitive to changes in 5-HT. Five healthy subjects were scanned on a high resolution PET scanner twice on the same day, before and approximately 5 hours after ingesting capsules containing an amino acid mixture that lacks tryptophan. For each scan, emission data were acquired for 120 min after intravenous bolus injection of [11 C]P943. Binding potential (BPND ) values were estimated from parametric images using the second version of the multilinear reference tissue model (MRTM2, t* = 20 min) with cerebellar grey matter used as a reference region. The change in [11 C]P943 binding (ΔBPND , %) was calculated as (BPND,post - BPND,pre )/(BPND,pre ) × 100, and correlation analysis was performed to measure linear associations of ΔBPND between raphe and other regions of interest (ROIs). ΔBPND ranged from -6% to 45% in the raphe, with positive values indicating reduced competition from 5-HT. In cortical regions, ΔBPND ranged from -28% to 7%. While these changes did not reach significance, there were significant negative correlations of ΔBPND of the raphe with those of cerebral cortical regions and the thalamus (e.g., r = -.96, p = .011 for average cortex). These findings support the hypothesis that raphe serotonin is a critical modulator of cortical serotonin release via projecting neurons in healthy human subjects.
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Affiliation(s)
- Stephen R Baldassarri
- Section of Pulmonary, Critical Care, and Sleep Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Eunkyung Park
- Department of Radiology and Biomedical Imaging, PET Center, Yale School of Medicine, New Haven, CT, USA.,Division of Nuclear Medicine, Department of Radiology, University of Iowa Hospitals and Clinics, Iowa City, IA, USA
| | - Sjoerd J Finnema
- Department of Radiology and Biomedical Imaging, PET Center, Yale School of Medicine, New Haven, CT, USA
| | - Beata Planeta
- Department of Radiology and Biomedical Imaging, PET Center, Yale School of Medicine, New Haven, CT, USA
| | - Nabeel Nabulsi
- Department of Radiology and Biomedical Imaging, PET Center, Yale School of Medicine, New Haven, CT, USA
| | - Soheila Najafzadeh
- Department of Radiology and Biomedical Imaging, PET Center, Yale School of Medicine, New Haven, CT, USA
| | - Jim Ropchan
- Department of Radiology and Biomedical Imaging, PET Center, Yale School of Medicine, New Haven, CT, USA
| | - Yiyun Huang
- Department of Radiology and Biomedical Imaging, PET Center, Yale School of Medicine, New Haven, CT, USA
| | - Jonas Hannestad
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - Kathleen Maloney
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - Zubin Bhagwagar
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - Richard E Carson
- Department of Radiology and Biomedical Imaging, PET Center, Yale School of Medicine, New Haven, CT, USA
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31
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Tryptophan Improves Memory Independent of Its Role as a Serotonin Precursor: Potential Involvement of Microtubule Proteins. J Mol Neurosci 2020; 70:559-567. [DOI: 10.1007/s12031-019-01457-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 11/28/2019] [Indexed: 12/17/2022]
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32
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Merino JJ, Cabaña-Muñoz ME, Toledano Gasca A, Garcimartín A, Benedí J, Camacho-Alonso F, Parmigiani-Izquierdo JM. Elevated Systemic L-Kynurenine/L-Tryptophan Ratio and Increased IL-1 Beta and Chemokine (CX3CL1, MCP-1) Proinflammatory Mediators in Patients with Long-Term Titanium Dental Implants. J Clin Med 2019; 8:jcm8091368. [PMID: 31480733 PMCID: PMC6780981 DOI: 10.3390/jcm8091368] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 08/27/2019] [Accepted: 08/28/2019] [Indexed: 01/04/2023] Open
Abstract
Titanium is the mean biocompatible metal found in dental titanium alloys (Ti-6Al-4V). The safety of certain dental biomaterial amalgams has been questioned in patients. The levels of several systemic cytokines (interleukin (IL)-1 beta, IL-4: pg/mL) and chemokines (monocyte chemoattractant protein-1 (MCP-1), soluble fractalkine (CX3CL1: pg/mL) were determined using ELISA and compared between these study groups. The study included 30 controls without dental materials (cont), 57 patients with long-term titanium dental implants plus amalgams (A + I group) as well as 55 patients with long-term dental amalgam alone (A group). All patients (except controls) have had dental titanium implants (Ti-6Al-4V) and/or amalgams for at least 10 years (average: 15 years). We evaluated whether systemic levels of cytokines/chemokines, kyn/L-trp ratio and aromatic amino acid levels (HPLC: mM/L, Phe, L-Trp, His, Treo) could be altered in patients with long-term dental titanium and/or amalgams. These systemic markers were evaluated in 142 patients. The A + I group had higher L-Kynurenine/L-Tryptophan ratios than patients with long-term dental amalgam fillings alone (A). In addition, levels of IL-1 Beta cytokine, CX3CL1 and MCP-1 chemokines were higher in the A + I group than in the A group (A). The increased L-kyn/L-trp ratio and MCP-1 and fractalkine receptor (CX3CR1) elevations could suggest enhanced chemotactic responses by these chemokines in the A + I group.
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Affiliation(s)
- José Joaquín Merino
- Departamento de Farmacología, Farmacognosia y Botánica, Facultad de Farmacia, Universidad Complutense de Madrid (U.C.M), c/Plaza Ramón y Cajal s/n, 28040 Madrid, Spain.
- Centro CIROM, Centro de Implantología y Rehabilitación Oral Multidisciplinaria, 30001 Murcia, Spain.
| | | | | | - Alba Garcimartín
- Departamento de Farmacología, Farmacognosia y Botánica, Facultad de Farmacia, Universidad Complutense de Madrid (U.C.M), c/Plaza Ramón y Cajal s/n, 28040 Madrid, Spain
| | - Juana Benedí
- Departamento de Farmacología, Farmacognosia y Botánica, Facultad de Farmacia, Universidad Complutense de Madrid (U.C.M), c/Plaza Ramón y Cajal s/n, 28040 Madrid, Spain
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Birkl P, Chow J, McBride P, Kjaer JB, Kunze W, Forsythe P, Harlander-Matauschek A. Effects of Acute Tryptophan Depletion on Repetitive Behavior in Laying Hens. Front Vet Sci 2019; 6:230. [PMID: 31355217 PMCID: PMC6637846 DOI: 10.3389/fvets.2019.00230] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 06/25/2019] [Indexed: 11/18/2022] Open
Abstract
Repetitive pecking at the feather cover of other birds (FP) is one of the most important welfare problems in domestic birds. It is not only characterized by motor symptoms, but also by an innate vulnerability of the serotonergic system. Moreover, the serotonergic system influences cognitive function. Acute tryptophan depletion (ATD) is a widely used method for studying serotonergic function in mammals and has been recently validated in birds. However, a tryptophan-deficient amino acid mixture has never been tested on groups of birds to impact their social behavior, including repetitive feather pecking, nor has it been given to potentially impact their cognition and motor performance. One hundred and sixty White Leghorn laying hens consisting of two genetic lines divergently selected to perform high (H) or low (L) levels of FP, and an unselected control line (UC), were kept in 10 groups consisting of 4 H, 3 L, and 9 UC genotypes. In a counterbalanced order, half of the groups were first subjected to an ATD treatment, while the other half were first given a balanced control (BC) treatment, and vice versa, after which their feather pecking behavior was observed. The effect of ATD/BC on repetitive pecking, motor performance, and cognition was investigated in a 5-s delayed reward task in an operant chamber with 10 phenotypic feather peckers, 10 recipients of feather pecking, and 10 bystanders (who neither performed nor received feather pecks). ATD given to groups of birds induced gentle, repetitive feather pecking in all genotypes. Following ATD, phenotypic feather peckers performed more poorly during the delayed reward task, as seen by their higher number of repetitive, non-rewarded key, and non-key pecks in the operant chamber. In conclusion, ATD impacted the hens' social behavior by increasing the number of repetitive gentle feather pecks at conspecifics. Furthermore, feather peckers were more likely to peck while waiting for a reward after ATD, suggesting a role for the serotonergic system on cognition in these birds.
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Affiliation(s)
- Patrick Birkl
- Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada
| | - Jacqueline Chow
- Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada
| | - Peter McBride
- Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada
| | - Joergen B Kjaer
- Friedrich-Loeffler-Institute, Federal Research Institute for Animal Health, Institute of Animal Welfare and Animal Husbandry, Celle, Germany
| | - Wolfgang Kunze
- Department of Medicine, Brain-Body Institute and Firestone Institute for Respiratory Health, McMaster University, Hamilton, ON, Canada
| | - Paul Forsythe
- Department of Medicine, Brain-Body Institute and Firestone Institute for Respiratory Health, McMaster University, Hamilton, ON, Canada
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Lukić I, Getselter D, Koren O, Elliott E. Role of Tryptophan in Microbiota-Induced Depressive-Like Behavior: Evidence From Tryptophan Depletion Study. Front Behav Neurosci 2019; 13:123. [PMID: 31231198 PMCID: PMC6558209 DOI: 10.3389/fnbeh.2019.00123] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 05/20/2019] [Indexed: 12/26/2022] Open
Abstract
During the past decade, there has been a substantial rise in the knowledge about the effects of gut microbiota on host physiology and behavior, including depressive behavior. Initial studies determined that gut microbiota can regulate host tryptophan levels, which is a main serotonin precursor. A dysfunctional serotonergic system is considered to be one of the main factors contributing to the development of depression. Therefore, we hypothesized that regulation of brain tryptophan and serotonin can explain, at least partly, the effects of microbiota on depressive behavior. To test this hypothesis, we examined depressive-like behavior and brain levels of serotonin and tryptophan, of germ free (GF) and specific-pathogen free (SPF) mice under basal conditions, or after acute tryptophan depletion (ATD) procedure, which is a method to decrease tryptophan and serotonin levels in the brain. In basal conditions, GF mice exhibited less depressive-like behavior in sucrose preference, tail-suspension and forced swim tests, compared to SPF mice. In addition, in mice that were not subjected to ATD, GF mice displayed higher levels of tryptophan, serotonin and 5-hydroxyindoleacetic acid (the main degradation product of serotonin) in medial prefrontal cortex (mPFC) and hippocampus (HIPPO), compared to SPF mice. Interestingly, ATD increased depressive-like behavior of GF, but not of SPF mice. These behavioral changes were accompanied by a stronger reduction of tryptophan, serotonin and 5-hydroxyindoleacetic acid in mPFC and HIPPO in GF mice after ATD, when compared to SPF mice. Therefore, the serotonergic system of GF mice is more vulnerable to the acute challenge of tryptophan reduction, and GF mice after tryptophan reduction behave more similarly to SPF mice. These data provide functional evidence that microbiota affects depression-like behavior through influencing brain tryptophan accessibility and the serotonergic system.
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Affiliation(s)
- Iva Lukić
- Molecular and Behavioral Neuroscience, Bar-Ilan University, Safed, Israel
| | - Dmitriy Getselter
- Molecular and Behavioral Neuroscience, Bar-Ilan University, Safed, Israel
| | - Omry Koren
- Microbiome Research Laboratories, The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
| | - Evan Elliott
- Molecular and Behavioral Neuroscience, Bar-Ilan University, Safed, Israel
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Zhang X, Huettel SA, Mullette-Gillman OA, Guo H, Wang L. Exploring common changes after acute mental stress and acute tryptophan depletion: Resting-state fMRI studies. J Psychiatr Res 2019; 113:172-180. [PMID: 30959228 DOI: 10.1016/j.jpsychires.2019.03.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 03/23/2019] [Accepted: 03/27/2019] [Indexed: 11/27/2022]
Abstract
Stress and low serotonin levels are important biological factors in depression and anxiety etiologies. Although studies indicate that low serotonin levels, stress, and other factors may interact in depression/anxiety psychopathology, few studies have investigated the potentially shared neural substrates. We conducted resting-state fMRI scans pre- and post-stress task, and under control and tryptophan depletion condition, to explore the common changes induced by acute mental stress (AMS) and acute tryptophan depletion (ATD). The present study targeted regions within core brain networks - default mode network, salience network, executive control network, and emotion network - reported altered in AMS and ATD, and used regional homogeneity (ReHo) and functional connectivity (FC) analyses to explore their overlapped effects. We additionally examined the relationships among core neural networks - operationalized as an index of resource allocation bias that quantifies the shift from internal to external modes of processing. We found both manipulations induced increased ReHo of the amygdala and decreased ReHo of the posterior cingulate cortex (PCC). The PCC-amygdala FC was negatively correlated with the change of negative affect, whereas the right dorsolateral prefrontal cortex and right anterior insula FC was positively associated with anxiety level. In addition, we found that a greater shift to an external mode was correlated with higher anxiety level under both conditions. Common changes induced by acute mental stress and acute tryptophan depletion confirmed our hypothesis that AMS and ATD induce changes in common neural pathways, which in turn might mark vulnerability to depression and anxiety.
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Affiliation(s)
- Xue Zhang
- Center for Biomedical Imaging Research, Department of Biomedical Engineering, Tsinghua University School of Medicine, Beijing, China
| | - Scott A Huettel
- Center for Cognitive Neuroscience, Department of Psychology & Neuroscience, Duke University, Durham, USA
| | | | - Hua Guo
- Center for Biomedical Imaging Research, Department of Biomedical Engineering, Tsinghua University School of Medicine, Beijing, China
| | - Lihong Wang
- Department of Psychiatry, University of Connecticut School of Medicine, Farmington, USA.
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36
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Measuring endogenous changes in serotonergic neurotransmission with [ 11C]Cimbi-36 positron emission tomography in humans. Transl Psychiatry 2019; 9:134. [PMID: 30975977 PMCID: PMC6459901 DOI: 10.1038/s41398-019-0468-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 03/24/2019] [Indexed: 12/28/2022] Open
Abstract
Developing positron emission tomography (PET) radioligands for the detection of endogenous serotonin release will enable the investigation of serotonergic deficits in many neuropsychiatric disorders. The present study investigates how acute challenges that aim to increase or decrease cerebral serotonin levels affect binding of the serotonin 2A receptor (5-HT2AR) agonist radioligand [11C]Cimbi-36. In a randomized, double-blind, placebo-controlled, three-arm design, 23 healthy volunteers were PET scanned twice with [11C]Cimbi-36: at baseline and following double-blind assignment to one of three interventions (1) infusion of the selective serotonin reuptake inhibitor (SSRI) citalopram preceded by oral dosing of the 5-HT1AR antagonist pindolol, (n = 8) (2) acute tryptophan depletion (ATD) (n = 7) and (3) placebo (n = 8). Two-sample t-tests revealed no significant group differences in percent change of neocortical [11C]Cimbi-36 binding from baseline to intervention between placebo and citalopram/pindolol (p = 0.4) or between placebo and ATD (p = 0.5). Notably, there was a significantly larger within-group variation in 5-HT2AR binding after intervention with citalopram/pindolol, as compared with placebo (p = 0.007). These findings suggest that neither ATD nor a combination of citalopram and pindolol elicit acute unidirectional changes in serotonin levels sufficient to be detected with [11C]Cimbi-36 PET in neocortex. We suggest that the large interindividual variation in 5-HT2AR binding after citalopram/pindolol reflects that after an acute SSRI intervention, individuals respond substantially different in terms of their brain serotonin levels. Our observation has a potential impact for the understanding of patient responses to SSRI.
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Deza-Araujo YI, Neukam PT, Marxen M, Müller DK, Henle T, Smolka MN. Acute tryptophan loading decreases functional connectivity between the default mode network and emotion-related brain regions. Hum Brain Mapp 2018; 40:1844-1855. [PMID: 30585373 DOI: 10.1002/hbm.24494] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 11/26/2018] [Accepted: 11/29/2018] [Indexed: 12/21/2022] Open
Abstract
It has been shown that the functional architecture of the default mode network (DMN) can be affected by serotonergic challenges and these effects may provide insights on the neurobiological bases of depressive symptomatology. To deepen our understanding of this possible interplay, we used a double-blind, randomized, cross-over design, with a control condition and two interventions to decrease (tryptophan depletion) and increase (tryptophan loading) brain serotonin synthesis. Resting-state fMRI from 85 healthy subjects was acquired for all conditions 3 hr after the ingestion of an amino acid mixture containing different amounts of tryptophan, the dietary precursor of serotonin. The DMN was derived for each participant and session. Permutation testing was performed to detect connectivity changes within the DMN as well as between the DMN and other brain regions elicited by the interventions. We found that tryptophan loading increased tryptophan plasma levels and decreased DMN connectivity with visual cortices and several brain regions involved in emotion and affect regulation (i.e., putamen, subcallosal cortex, thalamus, and frontal cortex). Tryptophan depletion significantly reduced tryptophan levels but did not affect brain connectivity. Subjective ratings of mood, anxiety, sleepiness, and impulsive choice were not strongly affected by any intervention. Our data indicate that connectivity between the DMN and emotion-related brain regions might be modulated by changes in the serotonergic system. These results suggest that functional changes in the brain associated with different brain serotonin levels may be relevant to understand the neural bases of depressive symptoms.
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Affiliation(s)
- Yacila I Deza-Araujo
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Philipp T Neukam
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Michael Marxen
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Dirk K Müller
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Thomas Henle
- Institute of Food Chemistry, Technische Universität Dresden, Dresden, Germany
| | - Michael N Smolka
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
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Tanaka M, Sato A, Kasai S, Hagino Y, Kotajima-Murakami H, Kashii H, Takamatsu Y, Nishito Y, Inagaki M, Mizuguchi M, Hall FS, Uhl GR, Murphy D, Sora I, Ikeda K. Brain hyperserotonemia causes autism-relevant social deficits in mice. Mol Autism 2018; 9:60. [PMID: 30498565 PMCID: PMC6258166 DOI: 10.1186/s13229-018-0243-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 11/08/2018] [Indexed: 12/19/2022] Open
Abstract
Background Hyperserotonemia in the brain is suspected to be an endophenotype of autism spectrum disorder (ASD). Reducing serotonin levels in the brain through modulation of serotonin transporter function may improve ASD symptoms. Methods We analyzed behavior and gene expression to unveil the causal mechanism of ASD-relevant social deficits using serotonin transporter (Sert) knockout mice. Results Social deficits were observed in both heterozygous knockout mice (HZ) and homozygous knockout mice (KO), but increases in general anxiety were only observed in KO mice. Two weeks of dietary restriction of the serotonin precursor tryptophan ameliorated both brain hyperserotonemia and ASD-relevant social deficits in Sert HZ and KO mice. The expression of rather distinct sets of genes was altered in Sert HZ and KO mice, and a substantial portion of these genes was also affected by tryptophan depletion. Tryptophan depletion in Sert HZ and KO mice was associated with alterations in the expression of genes involved in signal transduction pathways initiated by changes in extracellular serotonin or melatonin, a derivative of serotonin. Only expression of the AU015836 gene was altered in both Sert HZ and KO mice. AU015836 expression and ASD-relevant social deficits normalized after dietary tryptophan restriction. Conclusions These findings reveal a Sert gene dose-dependent effect on brain hyperserotonemia and related behavioral sequelae in ASD and a possible therapeutic target to normalize brain hyperserotonemia and ASD-relevant social deficits. Electronic supplementary material The online version of this article (10.1186/s13229-018-0243-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Miho Tanaka
- 1Department of Psychiatry and Behavioral Sciences, Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 Japan.,2Molecular and Cellular Medicine, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan.,3Department of Developmental Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Atsushi Sato
- 1Department of Psychiatry and Behavioral Sciences, Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 Japan.,4Department of Pediatrics, The University of Tokyo Hospital, Tokyo, Japan
| | - Shinya Kasai
- 1Department of Psychiatry and Behavioral Sciences, Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 Japan
| | - Yoko Hagino
- 1Department of Psychiatry and Behavioral Sciences, Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 Japan
| | - Hiroko Kotajima-Murakami
- 1Department of Psychiatry and Behavioral Sciences, Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 Japan
| | - Hirofumi Kashii
- 1Department of Psychiatry and Behavioral Sciences, Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 Japan
| | - Yukio Takamatsu
- 1Department of Psychiatry and Behavioral Sciences, Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 Japan
| | - Yasumasa Nishito
- 5Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Masumi Inagaki
- 3Department of Developmental Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Masashi Mizuguchi
- 6Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - F Scott Hall
- 7Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, The University of Toledo, Toledo, OH USA
| | - George R Uhl
- 8Branch of Molecular Neurobiology, National Institute on Drug Abuse, Baltimore, MD USA.,9Research Service, New Mexico VA Health Care System, Albuquerque, NM USA
| | - Dennis Murphy
- 10Laboratory of Clinical Science, National Institutes of Health, Bethesda, MD USA
| | - Ichiro Sora
- 11Department of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Kazutaka Ikeda
- 1Department of Psychiatry and Behavioral Sciences, Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 Japan.,2Molecular and Cellular Medicine, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
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Yang KC, Takano A, Halldin C, Farde L, Finnema SJ. Serotonin concentration enhancers at clinically relevant doses reduce [ 11C]AZ10419369 binding to the 5-HT 1B receptors in the nonhuman primate brain. Transl Psychiatry 2018; 8:132. [PMID: 30013068 PMCID: PMC6048172 DOI: 10.1038/s41398-018-0178-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 02/14/2018] [Accepted: 04/03/2018] [Indexed: 12/25/2022] Open
Abstract
The serotonin (5-HT) system plays an important role in the pathophysiology and treatment of several major psychiatric disorders. Currently, no suitable positron emission tomography (PET) imaging paradigm is available to assess 5-HT release in the living human brain. [11C]AZ10419369 binds to 5-HT1B receptors and is one of the most 5-HT-sensitive radioligands available. This study applied 5-HT concentration enhancers which can be safely studied in humans, and examined their effect on [11C]AZ10419369 binding at clinically relevant doses, including amphetamine (1 mg/kg), 3,4-methylenedioxymethamphetamine (MDMA; 1 mg/kg) or 5-hydroxy-L-tryptophan (5-HTP; 5 mg/kg). Twenty-six PET measurements (14 for amphetamine, 6 for MDMA and 6 for 5-HTP) using a bolus and constant infusion protocol were performed in four cynomolgus monkeys before or after drug administration. Binding potential (BPND) values were determined with the equilibrium method (integral interval: 63-123 min) using cerebellum as the reference region. BPND values were significantly decreased in several examined brain regions after administration of amphetamine (range: 19-31%), MDMA (16-25%) or 5-HTP (13-31%). Reductions in [11C]AZ10419369 binding were greater in striatum than cortical regions after administration of 5-HTP, while no prominent regional differences were found for amphetamine and MDMA. In conclusion, [11C]AZ10419369 binding is sensitive to changes in 5-HT concentration induced by amphetamine, MDMA or 5-HTP. The robust changes in BPND, following pretreatment drugs administered at clinically relevant doses, indicate that the applied PET imaging paradigms hold promise to be successfully used in future human studies.
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Affiliation(s)
- Kai-Chun Yang
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
| | - Akihiro Takano
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Christer Halldin
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Lars Farde
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
- Personalized Health Care and Biomarkers, AstraZeneca PET Science Center at Karolinska Institutet, Stockholm, Sweden
| | - Sjoerd J Finnema
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, USA
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Neukam PT, Kroemer NB, Deza Araujo YI, Hellrung L, Pooseh S, Rietschel M, Witt SH, Schwarzenbolz U, Henle T, Smolka MN. Risk-seeking for losses is associated with 5-HTTLPR, but not with transient changes in 5-HT levels. Psychopharmacology (Berl) 2018; 235:2151-2165. [PMID: 29730700 DOI: 10.1007/s00213-018-4913-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 04/17/2018] [Indexed: 10/17/2022]
Abstract
RATIONALE Serotonin (5-HT) plays a key role in different aspects of value-based decision-making. A recent framework proposed that tonic 5-HT (together with dopamine, DA) codes future average reward expectations, providing a baseline against which possible choice outcomes are compared to guide decision-making. OBJECTIVES To test whether high 5-HT levels decrease loss aversion, risk-seeking for gains, and risk-seeking for losses. METHODS In a first session, 611 participants were genotyped for 5-HTTLPR and performed a mixed gambles (MGA) task and two probability discounting tasks for gains and losses, respectively (PDG/PDL). Afterwards, a subsample of 105 participants (44 with S/S, 6 with S/L, 55 with L/L genotype) completed the pharmacological study using a crossover design with tryptophan depletion (ATD), loading (ATL), and balanced (BAL) conditions. The same decision constructs were assessed. RESULTS We found increased risk-seeking for losses in S/S compared to L/L individuals at the first visit (p = 0.002). Neither tryptophan depletion nor loading affected decision-making, nor did we observe an interaction between intervention and 5-HTTLPR genotype. CONCLUSION Our data do not support the idea that transient changes of tonic 5-HT affect value-based decision-making. We provide evidence for an association of 5-HTTLPR with risk-seeking for losses, independent of acute 5-HT levels. This indicates that the association of 5-HTTLPR and risk-seeking for losses is mediated via other mechanisms, possibly by differences in the structural development of neural circuits of the 5-HT system during early life phases.
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Affiliation(s)
- Philipp T Neukam
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Nils B Kroemer
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany.,Department of Psychiatry and Psychotherapy, University of Tübingen, Tübingen, Germany
| | - Yacila I Deza Araujo
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Lydia Hellrung
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany.,Department of Economics, University of Zürich, Zürich, Switzerland
| | - Shakoor Pooseh
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Marcella Rietschel
- Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Stephanie H Witt
- Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Uwe Schwarzenbolz
- Institute of Food Chemistry, Technische Universität Dresden, Dresden, Germany
| | - Thomas Henle
- Institute of Food Chemistry, Technische Universität Dresden, Dresden, Germany
| | - Michael N Smolka
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany.
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Tryptophan supplementation and serotonin function: genetic variations in behavioural effects. Proc Nutr Soc 2018; 77:174-188. [DOI: 10.1017/s0029665117004451] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The neurotransmitter serotonin has a role in affective disorders such as depression and anxiety, as well as sleep, cognitive function and appetite. This review examines the evidence that serotonin-related genotypes may moderate the behavioural effects of supplementation with the serotonin precursor amino acidl-tryptophan (TRP), on which synthesis of serotonin (or 5-hydroxytryptamine; 5-HT) depends. However, 95 % of serotonin is synthesised and used in the periphery, and TRP is also metabolised via non-5-HT routes such as the kynurenine pathway. Moreover, understanding of genotypes involved in regulation of serotonin raises questions over the generalisability of TRP effects on behaviour across individuals with varied serotonergic genotypes. To date, only differences between variants of the 5-HT transporter-linked promoter region (5-HTTLPR) have been investigated in relation to behavioural effects of TRP supplementation. Effects of 5-HTTLPR genotypes are usually compared between the alleles that are either high (L/L′) or low (S/S′) expressing of mRNA for the 5-HT transporter receptor. Yet, another key genetic variable is sex: in women, the S/S′ genotype predicts sensitivity to improved mood and reduced cortisol by TRP supplementation, during stressful challenges, whereas the L/L′ genotype protects against stress-induced mood deterioration. In men, the L/L′ genotype may confer risk of stress-induced increases in negative affect; there are insufficient data to assess effects on male S/S′ genotypes. However, better-powered studies to detect sex by genotype by stress by TRP interactions, as well as consideration of more genotypes, are needed before strong conclusions and recommendations for behavioural effects of TRP treatment can be reached.
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Lattanzio SM. Fibromyalgia Syndrome: A Metabolic Approach Grounded in Biochemistry for the Remission of Symptoms. Front Med (Lausanne) 2017; 4:198. [PMID: 29250522 PMCID: PMC5715322 DOI: 10.3389/fmed.2017.00198] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 10/27/2017] [Indexed: 12/11/2022] Open
Abstract
Fibromyalgia syndrome (FMS) is a chronic, complex, and heterogeneous disorder of still poorly understood etiopathophysiology associated with important musculoskeletal widespread pain, fatigue, non-restorative sleep, and mood disturbances. It is estimated to afflict 2–3% of the worldwide population, with clean prevalence among women. The objective of this paper is to propose a novel treatment for symptomatic remission of FMS, grounded in biochemistry and consisting in the withdrawal from the diet of molecules that can indirectly trigger the symptoms. The hypothesis develops from the evidence that low serotonin levels are involved in FMS. Serotonin is synthesized starting from the essential amino acid tryptophan. The presence of non-absorbed molecules in the gut, primarily fructose, reduces tryptophan absorption. Low tryptophan absorption leads to low serotonin synthesis that triggers FMS symptoms. Moreover not-absorbed sugars could also produce a microbiota deterioration activating a positive feedback loop: the increasing microbiota deterioration reduces the functionality of absorption both of fructose and tryptophan in the gut, entering a vicious circle. The therapeutic idea is to sustain serotonin synthesis allowing the proper tryptophan absorption. The core of the cure treatment is the exclusion from the diet of some carbohydrates and the marked reduction of some others. The main target is the limitation of total dietary fructose as marked as possible. It could be an effective strategy to get the remission of symptoms acting on the impaired biochemical pathways. The straying from the treatment is expected to cause the reappear of the symptoms.
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Ahmed M, Azmat A. Decreased brain serotonin turnover rate following administration of Sharbat-e-Ahmed Shah produces antidepressant and anxiolytic effect in rats. Metab Brain Dis 2017; 32:1785-1790. [PMID: 28687902 DOI: 10.1007/s11011-017-0065-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 06/27/2017] [Indexed: 12/31/2022]
Abstract
Sharbat-e-Ahmed Shah (SAS) has usually been used in Traditional Unani Medicine (TUM) for depression and insomnia but still not evaluated for its anti-depressant and Neuropharmacological activity. In the present study, a Human dose of SAS (0.6 ml/kg/d) was administered orally to the rats for 15 consecutive days. Antidepressant and anxiolytic were screened scientifically in rats by using Forced swim test and light and dark box test. At the end of study high-performance liquid chromatographic (HPLC) method with electrochemical (EC) detector was used for the measurement of blood and brain tryptophan and brain serotonin levels. The present reported results are according to what is known in TUM, where is prescribed as an antidepressant agent. After the administration, SAS (at a human dose for 15 days) reduced the immobility time in rats analogous to Imipramine (positive control) indicating the antidepressant effect of SAS. In the present study, Diazepam or SAS (0.6 ml/kg/day) treated rats stayed in the illuminated side of the light-dark box, as compare to control rats (Veh, 134.62 ± 4.430 s; SAS 0.6 ml/kg, 192.2 ± 8.11 s; DZP 1.0 mg/kg, 205.21.20 ± 10.26 s, p < 0.05). It was also observed that SAS increased the availability of tryptophan in blood and brain and hence increases 5-hydroxytryptamine (Serotonin: 5HT) in the brain. At the end, it was concluded that SAS contains some active principles which increase the availability of neurochemical (tryptophan and 5HT) and decrease the 5HT turnover rate thus causes antidepressant and anxiolytic effects in experimental animals.
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Affiliation(s)
- Muhammad Ahmed
- Department of Pharmacology, Faculty of Pharmacy, Umm-Al-Qura University, Makkah, Saudi Arabia.
| | - Aisha Azmat
- Department of Physiology, Faculty of Medicine, Umm-Al-Qura University, Makkah, Saudi Arabia
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Caldenhove S, Borghans L, Blokland A, Sambeth A. Role of acetylcholine and serotonin in novelty processing using an oddball paradigm. Behav Brain Res 2017; 331:199-204. [DOI: 10.1016/j.bbr.2017.05.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 05/09/2017] [Accepted: 05/10/2017] [Indexed: 12/28/2022]
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Borghans LGJM, Blokland A, Sambeth A. Effects of biperiden and acute tryptophan depletion and their combination on verbal word memory and EEG. Psychopharmacology (Berl) 2017; 234:1135-1143. [PMID: 28210777 PMCID: PMC5352740 DOI: 10.1007/s00213-017-4549-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 01/25/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND Research on the neurobiological foundations of memory has shown that multiple neurotransmitters play an important role in memory processing. To study the interaction between neurotransmitters such as acetylcholine and serotonin, pharmacological models can be used. In this study, we tested the effects of the muscarinic M1 antagonist biperiden, acute tryptophan depletion (ATD), and the interaction between the two on episodic memory using the verbal learning task. METHODS The study was conducted according to a double-blind, placebo-controlled, four-way crossover design. Seventeen participants received biperiden (2.0 mg), ATD (SolugelP), a combination of both, or a placebo in counterbalanced order with a wash out of at least 7 days. A verbal learning task was performed while recording electroencephalography. The task consisted of an immediate and delayed recall as well as a recognition part. RESULTS Results revealed decreased scores on the delayed recall after biperiden and ATD separately but no significant interaction between the two. However, the event-related potential components P3b, N400, and P600 did show an interaction during encoding. CONCLUSION These results indicate that both BIP and ATD impair episodic memory. However, an interaction between the serotonergic and cholinergic system on memory performance is not supported.
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Affiliation(s)
- Laura G J M Borghans
- Faculty of Psychology and Neuroscience, Department of Neuropsychology and Psychopharmacology, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands.
| | - Arjan Blokland
- Faculty of Psychology and Neuroscience, Department of Neuropsychology and Psychopharmacology, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
| | - Anke Sambeth
- Faculty of Psychology and Neuroscience, Department of Neuropsychology and Psychopharmacology, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
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Dong W, Liu Z, Qiu L, Wang W, Song X, Wang X, Li Y, Xin L, Wang L, Song L. The modulation role of serotonin in Pacific oyster Crassostrea gigas in response to air exposure. FISH & SHELLFISH IMMUNOLOGY 2017; 62:341-348. [PMID: 28159695 DOI: 10.1016/j.fsi.2017.01.043] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 01/24/2017] [Accepted: 01/27/2017] [Indexed: 06/06/2023]
Abstract
Serotonin, also known as 5-hydroxytryptamine (5-HT), is a critical neurotransmitter in the neuroendocrine-immune regulatory network and involved in regulation of the stress response in vertebrates and invertebrates. In the present study, serotonin was found to be widely distributed in the tissues of Pacific oyster Crassostrea gigas, including haemolymph, gonad, visceral ganglion, mantle, gill, labial palps and hepatopancreas, and its concentration increased significantly in haemolymph and mantle after the oysters were exposed to air for 1 d. The apoptosis rate of haemocytes was significantly declined after the oysters received an injection of extra serotonin, while the activity of superoxide dismutase (SOD) in haemolymph increased significantly. After the stimulation of serotonin during air exposure, the apoptosis rate of oyster haemocytes and the concentration of H2O2 in haemolymph were significantly decreased, while the SOD activity was significantly elevated. Furthermore, the survival rate of oysters from 4th to 6th d after injection of serotonin was higher than that of FSSW group and air exposure group. The results clearly indicated that serotonin could modulate apoptotic effect and redox during air exposure to protect oysters from stress.
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Affiliation(s)
- Wenjing Dong
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhaoqun Liu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Limei Qiu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Weilin Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaorui Song
- Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian 116023, China
| | - Xiudan Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yiqun Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lusheng Xin
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lingling Wang
- Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian 116023, China.
| | - Linsheng Song
- Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian 116023, China
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Kynurenine pathway metabolism and the microbiota-gut-brain axis. Neuropharmacology 2017; 112:399-412. [DOI: 10.1016/j.neuropharm.2016.07.002] [Citation(s) in RCA: 311] [Impact Index Per Article: 44.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 06/30/2016] [Accepted: 07/04/2016] [Indexed: 02/07/2023]
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Linden M, Helmbold K, Kempf J, Sippas S, Filss C, Langen KJ, Eisert A, Zepf FD. Dietary tryptophan depletion in humans using a simplified two amino acid formula - a pilot study. Food Nutr Res 2016; 60:29272. [PMID: 27989269 PMCID: PMC5165058 DOI: 10.3402/fnr.v60.29272] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2015] [Revised: 09/26/2016] [Accepted: 11/03/2016] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Acute tryptophan depletion (ATD) is a well-established dietary method in translational brain research used to briefly lower central nervous serotonin (5-hydroxytryptamine (5-HT)) synthesis. A simplified two amino acid ATD formula (ATDPHE/LEU) was developed while reducing the overall amount of amino acids (AAs), with the objective of administration especially in children and adolescents in future studies. OBJECTIVE This study investigated tryptophan (TRP) influx rates across the blood-brain barrier (BBB) after dietary ATDPHE/LEU administration relative to the ATD Moja-De protocol that has been established for use in children and adolescents. DESIGN Seventy-two healthy adults (50% females) were randomized into four groups and administered ATD Moja-De, its TRP-balanced control condition (BAL), ATDPHE/LEU, or its respective control mixture (BALPHE/LEU) in a counterbalanced, double-blind, between-subjects design. Blood samples were collected at baseline and at hourly intervals for 6 h after AA intake. Questionnaires about mood, taste, and challenge tolerance were completed at fixed time points. RESULTS Both challenge mixtures significantly reduced central nervous TRP influx as calculated by Michaelis-Menten kinetics relative to baseline and the respective control conditions with only mild and comparable side effects. A greater decline in TRP influx over the BBB after ATDPHE/LEU administration when compared with ATD Moja-De was detected without group effects for taste, challenge tolerance, and mood. There was unintended initial short increase in plasma TRP concentrations observed after ATDPHE/LEU intake, and a possible redistribution between free and protein-bound TRP triggered by protein synthesis stimulated by the ingested AAs may account for this finding. Moreover, a decline in TRP influx after BALPHE/LEU administration over a 6-h period was observed, and the large amount of PHE in the BALPHE/LEU mixture may be a possible explanation for this particular phenomenon, which could have led to an unexpected increase in displacement of TRP at the BBB in this control condition. CONCLUSIONS This pilot study provides preliminary evidence for the possibility of lowering TRP influx as calculated by Michaelis-Menten kinetics into the brain by using a simplified ATD protocol in humans. The simplified composition of only two AAs, the lower overall AA amount, and the appropriate tolerance are characteristics of the newly developed ATDPHE/LEU protocol. Future studies focusing on the effects of the ATDPHE/LEU protocol and its respective control condition on CSF 5-HIAA concentrations, as well as neurochemical studies in rodents, are needed to further validate this newly developed AA mixture before definite conclusions about its usability in ATD-related research in humans, its specificity, and additional effects can be made.
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Affiliation(s)
- Maike Linden
- Clinic for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany.,JARA Translational Brain Medicine, Jülich Aachen Research Alliance, Jülich, Germany
| | - Katrin Helmbold
- Clinic for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany.,JARA Translational Brain Medicine, Jülich Aachen Research Alliance, Jülich, Germany
| | - Janina Kempf
- Clinic for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany.,JARA Translational Brain Medicine, Jülich Aachen Research Alliance, Jülich, Germany.,Faculty of Arts and Social Sciences, Maastricht University, Maastricht, The Netherlands
| | - Shabnam Sippas
- Clinic for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany.,JARA Translational Brain Medicine, Jülich Aachen Research Alliance, Jülich, Germany.,Faculty of Arts and Social Sciences, Maastricht University, Maastricht, The Netherlands
| | - Christian Filss
- Section JARA-Brain, Jülich-Aachen Research Alliance (JARA), Jülich, Germany
| | - Karl-Josef Langen
- Section JARA-Brain, Jülich-Aachen Research Alliance (JARA), Jülich, Germany.,Institute of Neuroscience and Medicine (INM-3, -4, -5), Research Centre Jülich, Jülich, Germany.,Department of Nuclear Medicine, RWTH Aachen University Hospital, Aachen, Germany
| | - Albrecht Eisert
- Department of Pharmacy, RWTH Aachen University, Aachen, Germany
| | - Florian Daniel Zepf
- Clinic for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany.,JARA Translational Brain Medicine, Jülich Aachen Research Alliance, Jülich, Germany.,Centre and 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, Australia.,Specialised Child and Adolescent Mental Health Services (CAMHS), Department of Health in Western Australia, Perth, Australia;
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Eisner P, Klasen M, Wolf D, Zerres K, Eggermann T, Eisert A, Zvyagintsev M, Sarkheil P, Mathiak KA, Zepf F, Mathiak K. Cortico-limbic connectivity in MAOA-L carriers is vulnerable to acute tryptophan depletion. Hum Brain Mapp 2016; 38:1622-1635. [PMID: 27935229 DOI: 10.1002/hbm.23475] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 11/09/2016] [Accepted: 11/14/2016] [Indexed: 01/12/2023] Open
Abstract
INTRODUCTION A gene-environment interaction between expression genotypes of the monoamine oxidase A (MAOA) and adverse childhood experience increases the risk of antisocial behavior. However, the neural underpinnings of this interaction remain uninvestigated. A cortico-limbic circuit involving the prefrontal cortex (PFC) and the amygdala is central to the suppression of aggressive impulses and is modulated by serotonin (5-HT). MAOA genotypes may modulate the vulnerability of this circuit and increase the risk for emotion regulation deficits after specific life events. Acute tryptophan depletion (ATD) challenges 5-HT regulation and may identify vulnerable neuronal circuits, contributing to the gene-environment interaction. METHODS Functional magnetic resonance imaging measured the resting-state state activity in 64 healthy males in a double-blind, placebo-controlled study. Cortical maps of amygdala correlation identified the impact of ATD and its interaction with low- (MAOA-L) and high-expression variants (MAOA-H) of MAOA on cortico-limbic connectivity. RESULTS Across all Regions of Interest (ROIs) exhibiting an ATD effect on cortico-limbic connectivity, MAOA-L carriers were more susceptible to ATD than MAOA-H carriers. In particular, the MAOA-L group exhibited a larger reduction of amygdala connectivity with the right prefrontal cortex and a larger increase of amygdala connectivity with the insula and dorsal PCC. CONCLUSION MAOA-L carriers were more susceptable to a central 5-HT challenge in cortico-limbic networks. Such vulnerability of the cortical serotonergic system may contribute to the emergence of antisocial behavior after systemic challenges, observed as gene-environment interaction. Hum Brain Mapp 38:1622-1635, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Patrick Eisner
- Department of Psychiatry, Psychotherapy, and Psychosomatics, Medical School, RWTH Aachen University, Aachen, Germany.,JARA-Translational Brain Medicine, Aachen, Germany
| | - Martin Klasen
- Department of Psychiatry, Psychotherapy, and Psychosomatics, Medical School, RWTH Aachen University, Aachen, Germany.,JARA-Translational Brain Medicine, Aachen, Germany
| | - Dhana Wolf
- Department of Psychiatry, Psychotherapy, and Psychosomatics, Medical School, RWTH Aachen University, Aachen, Germany.,JARA-Translational Brain Medicine, Aachen, Germany
| | - Klaus Zerres
- Department of Human Genetics, Medical School, RWTH Aachen University, Aachen, Germany
| | - Thomas Eggermann
- Department of Human Genetics, Medical School, RWTH Aachen University, Aachen, Germany
| | - Albrecht Eisert
- Department of Pharmacy, RWTH Aachen University, Aachen, Germany
| | - Mikhail Zvyagintsev
- Department of Psychiatry, Psychotherapy, and Psychosomatics, Medical School, RWTH Aachen University, Aachen, Germany.,JARA-Translational Brain Medicine, Aachen, Germany
| | - Pegah Sarkheil
- Department of Psychiatry, Psychotherapy, and Psychosomatics, Medical School, RWTH Aachen University, Aachen, Germany.,JARA-Translational Brain Medicine, Aachen, Germany
| | - Krystyna A Mathiak
- Department of Psychiatry, Psychotherapy, and Psychosomatics, Medical School, RWTH Aachen University, Aachen, Germany.,JARA-Translational Brain Medicine, Aachen, Germany
| | - Florian Zepf
- Department of Child and Adolescent Psychiatry, School of Psychiatry and Clinical Neurosciences and School of Pediatrics and Child Health; Faculty of Medicine, Dentistry and Health Sciences; The University of Western Australia (M561), Perth, Australia.,Department of Health in Western Australia, Specialized Child and Adolescent Mental Health Services (CAMHS), Perth, Australia
| | - Klaus Mathiak
- Department of Psychiatry, Psychotherapy, and Psychosomatics, Medical School, RWTH Aachen University, Aachen, Germany.,JARA-Translational Brain Medicine, Aachen, Germany
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Raab K, Kirsch P, Mier D. Understanding the impact of 5-HTTLPR, antidepressants, and acute tryptophan depletion on brain activation during facial emotion processing: A review of the imaging literature. Neurosci Biobehav Rev 2016; 71:176-197. [DOI: 10.1016/j.neubiorev.2016.08.031] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 07/28/2016] [Accepted: 08/26/2016] [Indexed: 12/22/2022]
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