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Grigolon RB, Trevizol AP, Gerchman F, Bambokian AD, Magee T, McIntyre RS, Gomes FA, Brietzke E, Mansur RB. Is Obesity A Determinant Of Success With Pharmacological Treatment For Depression? A Systematic Review, Meta-Analysis And Meta-Regression. J Affect Disord 2021; 287:54-68. [PMID: 33773359 DOI: 10.1016/j.jad.2021.03.032] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 03/09/2021] [Accepted: 03/11/2021] [Indexed: 12/18/2022]
Abstract
BACKGROUND The bidirectional association between Major Depressive Disorder (MDD) and obesity suggests that body mass index (BMI) at the baseline could influence remission rates (RR) with pharmacological treatment. We evaluated the influence of baseline BMI on the chances of remission among patients with MDD administered antidepressants. METHODS Based on the guidelines of the PRISMA statement, we conducted a systematic review on PubMed, Cochrane and Embase databases with subsequent meta-analysis and meta-regression. We included only randomized controlled trials evaluating the efficacy of antidepressants of different classes (monotherapy and combined therapies) that evidenced baseline BMI assessment. We created a model to describe the linear relationship between baseline BMI and RR. RESULTS Our systematic review yielded 70 studies with a total of 9,779 patients in the active group and 7,136 patients in the placebo group. In placebo controlled studies, BMI influenced the RR of patients randomized to active treatment. The RR for antidepressants in monotherapy was higher in normal weight to overweight patients rather than obese patients (33% vs 12%, respectively). Also in monotherapy, the RR is higher when the study is conducted on patients with a lower baseline BMI (p=0.029). For combined therapies, the pooled RR was higher in obese patients rather than in normal weight to overweight patients (75% vs 17%, respectively). LIMITATIONS BMI provides no information about body composition and obesity can be related to several potential confounders that potentially influence RR. CONCLUSION The RR with antidepressant therapy seems to be associated with baseline BMI in patients with MDD, although this simple variable was insufficiently explored so far.
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Affiliation(s)
- Ruth Bartelli Grigolon
- Post-Graduation Program in Psychiatry and Medical Psychology, Department of Psychiatry, Universidade Federal de Sao Paulo, Sao Paulo, SP, Brazil
| | - Alisson P Trevizol
- Temerty Centre for Therapeutic Brain Stimulation and the Mood and Anxiety Ambulatory Services at the Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada
| | - Fernando Gerchman
- Department of Internal Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Service of Endocrinology and Metabology, Hospital de Clinicas de Porto Alegre, Porto Alegre, RS, Brazil
| | | | - Taylor Magee
- Department of Psychiatry, Queen's University School of Medicine, Kingston, ON, Canada
| | - Roger S McIntyre
- Mood Disorders Psychopharmacology Unit (MDPU), Toronto Western Hospital, University Health Network, Toronto, ON, Canada; Department of Psychiatry, University of Toronto, Toronto, ON, Canada; Brain and Cognition Discovery Foundation (BCDF), Toronto, ON, Canada
| | - Fabiano A Gomes
- Department of Psychiatry, Queen's University School of Medicine, Kingston, ON, Canada; Inpatient Psychiatric Unit, Kingston General Hospital, Kingston Health Science Centre, Kingston, ON, Canada; Centre for Neuroscience Studies (CNS), Queen's University, Kingston, ON, Canada
| | - Elisa Brietzke
- Department of Psychiatry, Queen's University School of Medicine, Kingston, ON, Canada; Inpatient Psychiatric Unit, Kingston General Hospital, Kingston Health Science Centre, Kingston, ON, Canada; Centre for Neuroscience Studies (CNS), Queen's University, Kingston, ON, Canada.
| | - Rodrigo B Mansur
- Mood Disorders Psychopharmacology Unit (MDPU), Toronto Western Hospital, University Health Network, Toronto, ON, Canada
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Application of antidepressants in depression: A systematic review and meta-analysis. J Clin Neurosci 2020; 80:169-181. [PMID: 33099342 DOI: 10.1016/j.jocn.2020.08.013] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 08/09/2020] [Indexed: 12/27/2022]
Abstract
BACKGROUND The type and quantities of antidepressants are increasing, but the efficacy and safety of first-line and emerging drugs vary between studies. In this article, we estimated the efficacy and safety of first-line and emerging antidepressants (anti-inflammatory drugs and ketamine). METHOD ystematic search of EMBASE, ERIC, MEDLINE, psycARTICLES, and psycINFO without language restriction for studies on the depression, depressive symptoms, antidepressants, fluoxetine (Prozac), paroxetine, escitalopram, sertraline, fluvoxamine, venlafaxine, duloxetine, NSAIDs, anti-cytokine drugs or pioglitazone published before May 1st, 2019. Information on study characteristics, depression or depressive symptoms, antidepressants and the descriptive statistics (including efficacy and safety of antidepressants) was extracted independently by 2 investigators. Estimates were pooled using random-effects meta-analysis. Differences by study-level characteristics were estimated using stratified meta-analysis and meta-regression. The response and remission of antidepressants were used as clinical evaluation indicators, and the evaluation criteria were clinical depression scales. OR value of antidepressants as assessed by meta-analysis. RESULTS The literature search retrieved 5529 potentially relevant articles of which 49 studies were finally included. We compared the efficacy of antidepressants (seven first-line antidepressants (fluoxetine, paroxetine, escitalopram, sertraline, fluvoxamine, venlafaxine, duloxetine), there kinds of anti-inflammatory drugs(NASIDs, cytokine-inhibitor, pioglitazone) and ketamine) by comparing the OR values. CONCLUSION The three drugs with the highest OR value in response were NASID (OR = 3.62(1.58, 8.32)), venlafaxin (OR = 3.50(1.83, 6.70)) and ketamine (OR = 3.28(1.89, 5.68)), while the highest OR value in remission were NASID (OR = 3.17(1.60, 6.29)), ketamine (OR = 2.99(1.58, 5.67)) and venlafaxin (OR = 2.55(1.72, 3.78)). Through reading the literature, we found 69 SNPs associated with depression. Major depression was a debilitating disorder that could ultimately lead to enormous societal and economical challenge [1]. The number of person which affected by depression was up to 16% of the population worldwide. More than 300 million individuals were estimated to suffer depression these days [1,2]. Therefore, it is apparent that safety and effective treatments for depression are necessary. In the 1930 s, the first drug for schizophrenia was discovered. This finding was a landmark for the emerging of biological psychiatry. In the 1950 s, pharmacologists had stumbled upon the antidepressant effect of imipramine. Since then, every 30 years, the use of antidepressants had made a pulsatile leap. Selective serotonin reuptake inhibitors (SSRIs) are the most widely-prescribed psychiatric drugs for the treatment of depression. However, the efficacy was variable and incomplete: 60%-70% of the patients do not experience remission, while 30%-40% do not show a significant response [3,4]. Nevertheless, SSRIs, SNRIs (selective serotonin-norepinephrine reuptake inhibitors, which can block norepinephrine at the same time) and NaSSAs (norepinephrine and selective serotonin receptor agonist), constituted the first-line clinical drugs. Nearly 30 years after the outbreak of SSRIs, antidepressants have ushered in a new chapter. It has been found that anti-inflammatory drugs could also have the small and moderate antidepressant effect and it's widely discussed [5]. More than 40 anti-inflammatory drugs have been certificated to have antidepressant effects in preclinical and clinical studies [6]. The antidepressant that has been approved for use recently is ketamine. There is no comprehensive comparison of the efficacy of all these drugs. In this review, we tried to estimate the efficacy and safety of first-line antidepressants, anti-inflammatory drugs and ketamine. On the other hand, with the development of GWAS, SNPs related to depression have been reported, and the corresponding mechanisms have been elaborated, respectively. However, patients with these SNPs have not been treated with individualized drugs according to the mechanisms. We hope to push this process forward through the summary of this article. METHODS Search Strategy and Study Eligibility.
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Baranyi A, Amouzadeh-Ghadikolai O, von Lewinski D, Breitenecker RJ, Rothenhäusler HB, Robier C, Baranyi M, Theokas S, Meinitzer A. Revisiting the tryptophan-serotonin deficiency and the inflammatory hypotheses of major depression in a biopsychosocial approach. PeerJ 2017; 5:e3968. [PMID: 29109914 PMCID: PMC5671663 DOI: 10.7717/peerj.3968] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 10/08/2017] [Indexed: 12/19/2022] Open
Abstract
Background The aim of this cross-sectional study was to identify important biopsychosocial correlates of major depression. Biological mechanisms, including the inflammatory and the tryptophan-serotonin deficiency hypotheses of major depression, were investigated alongside health-related quality of life, life satisfaction, and social support. Methods The concentrations of plasma tryptophan, plasma kynurenine, plasma kynurenic acid, serum quinolinic acid, and the tryptophan breakdown to kynurenine were determined alongside health-related quality of life (Medical Outcome Study Form, SF-36), life satisfaction (Life Satisfaction Questionnaire, FLZ), and social support (Social Support Survey, SSS) in 71 depressive patients at the time of their in-patient admittance and 48 healthy controls. Results Corresponding with the inflammatory hypothesis of major depression, our study results suggest a tryptophan breakdown to kynurenine in patients with major depression, and depressive patients had a lower concentration of neuroprotective kynurenic acid in comparison to the healthy controls (Mann-Whitney-U: 1315.0; p = 0.046). Contradicting the inflammatory theory, the concentrations of kynurenine (t: -0.945; df = 116; p = 0.347) and quinolinic acid (Mann-Whitney-U: 1376.5; p = 0.076) in depressive patients were not significantly different between depressed and healthy controls. Our findings tend to support the tryptophan-serotonin deficiency hypothesis of major depression, as the deficiency of the serotonin precursor tryptophan in depressive patients (t: -3.931; df = 116; p < 0.001) suggests dysfunction of serotonin neurotransmission. A two-step hierarchical linear regression model showed that low tryptophan concentrations, low social support (SSS), occupational requirements (FLZ), personality traits (FLZ), impaired physical role (SF-36), and impaired vitality (SF-36) predict higher Beck Depression Inventory (BDI-II) scores. Discussion Our study results argue for the validity of a biopsychosocial model of major depression with multiple pathophysiological mechanisms involved.
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Affiliation(s)
- Andreas Baranyi
- Department of Psychiatry and Psychotherapeutic Medicine, Medical University of Graz, Graz, Austria
| | | | - Dirk von Lewinski
- Division of Cardiology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
| | | | - Hans-Bernd Rothenhäusler
- Department of Psychiatry and Psychotherapeutic Medicine, Medical University of Graz, Graz, Austria
| | | | - Maria Baranyi
- Department of Psychiatry and Psychotherapeutic Medicine, Medical University of Graz, Graz, Austria
| | - Simon Theokas
- Department of Psychiatry and Psychotherapeutic Medicine, Medical University of Graz, Graz, Austria
| | - Andreas Meinitzer
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria
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Si T, Wang G, Yang F, Fang Y, Fang M, Li J, Dong J, Shen X, Zhuo J, Rui Q, Wang J, Cuili H. Efficacy and safety of escitalopram in treatment of severe depression in Chinese population. Metab Brain Dis 2017; 32:891-901. [PMID: 28299626 DOI: 10.1007/s11011-017-9992-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 03/08/2017] [Indexed: 11/25/2022]
Abstract
Severe depression accounts for one-third of depressed patients. Increasing severity of depression usually hinders patients from achieving remission. This study evaluated the efficacy and safety of escitalopram in acute-phase treatment of severe major depressive disorder (MDD). A total of 225 participants with severe MDD (Diagnostic and Statistical Manual of Mental Disorders, 4th Edition criteria), with a current depressive episode and Montgomery-Asberg Depression Rating Scale (MADRS) score of ≥30 were enrolled. Participants received flexible dose escitalopram (10-20 mg/d) treatment for 8 weeks. Symptoms status was assessed by MADRS, Hamilton Depression Rating Scale (HAM-D-17), and Hamilton Anxiety Rating Scale (HAM-A). Quality of life was assessed by Short Form-12 (SF-12) and safety by adverse events, laboratory investigations, vital signs and physical findings. The remission (MADRS total score ≤ 10) rate in the intent-to-treat set (n = 207) was 72.9% at week 8. Significant improvement in symptoms compared to baseline, as evaluated by MADRS, HAMD-17 and HAMA scores at baseline, week 1, week 2, week 4, and week 8 (p < 0.0001 for all), was noted. Mean (SD) reduction from baseline in MADRS total score was 26.6 (11.38). Improvements in SF-12 score were significant (p = 0.000) and positively related to symptom improvement and negatively related to treatment-emergent adverse events (TEAEs). TEAEs were reported in 28.38% of participants. Most common TEAEs (>4%) were somnolence (9.0%), nausea (7.7%), hyperhidrosis (4.5%), dry mouth and dizziness (4.1% each). No serious TEAEs were reported. Escitalopram was effective and well-tolerated for acute-phase treatment of severe depression in Chinese population.
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Affiliation(s)
- Tianmei Si
- National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital/ Institute of Mental Health) and the Key Laboratory of Mental Health, Ministry of Health (Peking University), Beijing, China
| | - Gang Wang
- Beijing Anding Hospital of Capital University of Medical Sciences, Beijing, China
| | - Fude Yang
- Beijing Huilongguan Hospital, Beijing, China
| | - Yiru Fang
- Division of Mood Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | | | - Jijun Li
- Nanjing Brain Hospital, Jiangsu, China
| | - Jicheng Dong
- Qingdao Mental Health Center, Qingdao, Shandong, China
| | | | - Jianmin Zhuo
- Xi'an Janssen Pharmaceutical Ltd, Beijing, China
| | - Qing Rui
- Xi'an Janssen Pharmaceutical Ltd, Beijing, China
| | - Jinan Wang
- Xi'an Janssen Pharmaceutical Ltd, Beijing, China
| | - Hu Cuili
- Xi'an Janssen Pharmaceutical Ltd, Beijing, China.
- Therapeutic Area Physician, Medical Department, China R&D and Scientific Affairs, Xi'an Janssen Pharmaceutical Ltd., 19F, Tower 3, China Central Place, No. 77 Jian Guo Road, Chao Yang District, Beijing, 100025, China.
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Jakobsen JC, Katakam KK, Schou A, Hellmuth SG, Stallknecht SE, Leth-Møller K, Iversen M, Banke MB, Petersen IJ, Klingenberg SL, Krogh J, Ebert SE, Timm A, Lindschou J, Gluud C. Selective serotonin reuptake inhibitors versus placebo in patients with major depressive disorder. A systematic review with meta-analysis and Trial Sequential Analysis. BMC Psychiatry 2017; 17:58. [PMID: 28178949 PMCID: PMC5299662 DOI: 10.1186/s12888-016-1173-2] [Citation(s) in RCA: 186] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 12/20/2016] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The evidence on selective serotonin reuptake inhibitors (SSRIs) for major depressive disorder is unclear. METHODS Our objective was to conduct a systematic review assessing the effects of SSRIs versus placebo, 'active' placebo, or no intervention in adult participants with major depressive disorder. We searched for eligible randomised clinical trials in The Cochrane Library's CENTRAL, PubMed, EMBASE, PsycLIT, PsycINFO, Science Citation Index Expanded, clinical trial registers of Europe and USA, websites of pharmaceutical companies, the U.S. Food and Drug Administration (FDA), and the European Medicines Agency until January 2016. All data were extracted by at least two independent investigators. We used Cochrane systematic review methodology, Trial Sequential Analysis, and calculation of Bayes factor. An eight-step procedure was followed to assess if thresholds for statistical and clinical significance were crossed. Primary outcomes were reduction of depressive symptoms, remission, and adverse events. Secondary outcomes were suicides, suicide attempts, suicide ideation, and quality of life. RESULTS A total of 131 randomised placebo-controlled trials enrolling a total of 27,422 participants were included. None of the trials used 'active' placebo or no intervention as control intervention. All trials had high risk of bias. SSRIs significantly reduced the Hamilton Depression Rating Scale (HDRS) at end of treatment (mean difference -1.94 HDRS points; 95% CI -2.50 to -1.37; P < 0.00001; 49 trials; Trial Sequential Analysis-adjusted CI -2.70 to -1.18); Bayes factor below predefined threshold (2.01*10-23). The effect estimate, however, was below our predefined threshold for clinical significance of 3 HDRS points. SSRIs significantly decreased the risk of no remission (RR 0.88; 95% CI 0.84 to 0.91; P < 0.00001; 34 trials; Trial Sequential Analysis adjusted CI 0.83 to 0.92); Bayes factor (1426.81) did not confirm the effect). SSRIs significantly increased the risks of serious adverse events (OR 1.37; 95% CI 1.08 to 1.75; P = 0.009; 44 trials; Trial Sequential Analysis-adjusted CI 1.03 to 1.89). This corresponds to 31/1000 SSRI participants will experience a serious adverse event compared with 22/1000 control participants. SSRIs also significantly increased the number of non-serious adverse events. There were almost no data on suicidal behaviour, quality of life, and long-term effects. CONCLUSIONS SSRIs might have statistically significant effects on depressive symptoms, but all trials were at high risk of bias and the clinical significance seems questionable. SSRIs significantly increase the risk of both serious and non-serious adverse events. The potential small beneficial effects seem to be outweighed by harmful effects. SYSTEMATIC REVIEW REGISTRATION PROSPERO CRD42013004420.
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Affiliation(s)
- Janus Christian Jakobsen
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
- Department of Cardiology, Holbæk Hospital, Holbæk, Denmark
| | - Kiran Kumar Katakam
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
| | - Anne Schou
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
| | - Signe Gade Hellmuth
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
| | - Sandra Elkjær Stallknecht
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
| | - Katja Leth-Møller
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
| | - Maria Iversen
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
| | - Marianne Bjørnø Banke
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
| | - Iggiannguaq Juhl Petersen
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
| | - Sarah Louise Klingenberg
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
| | - Jesper Krogh
- Mental Health Centre Copenhagen, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sebastian Elgaard Ebert
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
| | - Anne Timm
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
| | - Jane Lindschou
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
| | - Christian Gluud
- The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812 Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, DK 2100 Copenhagen, Denmark
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Pehrson AL, Sanchez C. Altered γ-aminobutyric acid neurotransmission in major depressive disorder: a critical review of the supporting evidence and the influence of serotonergic antidepressants. DRUG DESIGN DEVELOPMENT AND THERAPY 2015; 9:603-24. [PMID: 25653499 PMCID: PMC4307650 DOI: 10.2147/dddt.s62912] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Evidence suggesting that central nervous system γ-aminobutyric acid (GABA) concentrations are reduced in patients with major depressive disorder (MDD) has been present since at least 1980, and this idea has recently gained support from more recent magnetic resonance spectroscopy data. These observations have led to the assumption that MDD’s underlying etiology is tied to an overall reduction in GABA-mediated inhibitory neurotransmission. In this paper, we review the mechanisms that govern GABA and glutamate concentrations in the brain, and provide a comprehensive and critical evaluation of the clinical data supporting reduced GABA neurotransmission in MDD. This review includes an evaluation of magnetic resonance spectroscopy data, as well as data on the expression and function of the GABA-synthesizing enzyme glutamic acid decarboxylase, GABA neuron-specific cell markers, such as parvalbumin, calretinin and calbindin, and the GABAA and GABAB receptors in clinical MDD populations. We explore a potential role for glial pathology in MDD-related reductions in GABA concentrations, and evidence of a connection between neurosteroids, GABA neurotransmission, and hormone-related mood disorders. Additionally, we investigate the effects of GABAergic pharmacological agents on mood, and demonstrate that these compounds have complex effects that do not universally support the idea that reduced GABA neurotransmission is at the root of MDD. Finally, we discuss the connections between serotonergic and GABAergic neurotransmission, and show that two serotonin-focused antidepressants – the selective serotonin-reuptake inhibitor fluoxetine and the multimodal antidepressant vortioxetine – modulate GABA neurotransmission in opposing ways, despite both being effective MDD treatments. Altogether, this review demonstrates that there are large gaps in our understanding of the relationship between GABA physiology and MDD, which must be remedied with more data from well-controlled empirical studies. In conclusion, this review suggests that the simplistic notion that MDD is caused by reduced GABA neurotransmission must be discarded in favor of a more nuanced and complex model of the role of inhibitory neurotransmission in MDD.
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Affiliation(s)
- Alan L Pehrson
- External Sourcing and Scientific Excellence, Lundbeck Research USA, Paramus, NJ, USA
| | - Connie Sanchez
- External Sourcing and Scientific Excellence, Lundbeck Research USA, Paramus, NJ, USA
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Frølund S, Nøhr M, Holm R, Brodin B, Nielsen C. Potential involvement of the proton-coupled amino acid transporter PAT1 (SLC36A1) in the delivery of pharmaceutical agents. J Drug Deliv Sci Technol 2013. [DOI: 10.1016/s1773-2247(13)50046-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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