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Collins HM, Gullino LS, Ozdemir D, Lazarenco C, Sudarikova Y, Daly E, Pilar Cuéllar F, Pinacho R, Bannerman DM, Sharp T. Rebound activation of 5-HT neurons following SSRI discontinuation. Neuropsychopharmacology 2024:10.1038/s41386-024-01857-8. [PMID: 38609530 DOI: 10.1038/s41386-024-01857-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 03/12/2024] [Accepted: 04/01/2024] [Indexed: 04/14/2024]
Abstract
Cessation of therapy with a selective serotonin (5-HT) reuptake inhibitor (SSRI) is often associated with an early onset and disabling discontinuation syndrome, the mechanism of which is surprisingly little investigated. Here we determined the effect on 5-HT neurochemistry of discontinuation from the SSRI paroxetine. Paroxetine was administered repeatedly to mice (once daily, 12 days versus saline controls) and then either continued or discontinued for up to 5 days. Whereas brain tissue levels of 5-HT and/or its metabolite 5-HIAA tended to decrease during continuous paroxetine, levels increased above controls after discontinuation, notably in hippocampus. In microdialysis experiments continuous paroxetine elevated hippocampal extracellular 5-HT and this effect fell to saline control levels on discontinuation. However, depolarisation (high potassium)-evoked 5-HT release was reduced by continuous paroxetine but increased above controls post-discontinuation. Extracellular hippocampal 5-HIAA also decreased during continuous paroxetine and increased above controls post-discontinuation. Next, immunohistochemistry experiments found that paroxetine discontinuation increased c-Fos expression in midbrain 5-HT (TPH2 positive) neurons, adding further evidence for a hyperexcitable 5-HT system. The latter effect was recapitulated by 5-HT1A receptor antagonist administration although gene expression analysis could not confirm altered expression of 5-HT1A autoreceptors following paroxetine discontinuation. Finally, in behavioural experiments paroxetine discontinuation increased anxiety-like behaviour, which partially correlated in time with the measures of increased 5-HT function. In summary, this study reports evidence that, across a range of experiments, SSRI discontinuation triggers a rebound activation of 5-HT neurons. This effect is reminiscent of neural changes associated with various psychotropic drug withdrawal states, suggesting a common unifying mechanism.
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Affiliation(s)
- Helen M Collins
- Dept. of Pharmacology, University of Oxford, Oxford, UK
- Dept. of Experimental Psychology, University of Oxford, Oxford, UK
| | | | - Dersu Ozdemir
- Dept. of Pharmacology, University of Oxford, Oxford, UK
| | | | | | | | - Fuencisla Pilar Cuéllar
- Dept. of Pharmacology, University of Oxford, Oxford, UK
- Departamento de Señalización Molecular y Celular, Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Departamento de Fisiología y Farmacología, Facultad de Medicina, Universidad de Cantabria, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Santander, Spain
| | - Raquel Pinacho
- Dept. of Experimental Psychology, University of Oxford, Oxford, UK
| | | | - Trevor Sharp
- Dept. of Pharmacology, University of Oxford, Oxford, UK.
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Zhang XY, Ye F, Yin ZH, Li YQ, Bao QN, Xia MZ, Chen ZH, Zhong WQ, Wu KX, Yao J, Liang FR. Research status and trends of physical activity on depression or anxiety: a bibliometric analysis. Front Neurosci 2024; 18:1337739. [PMID: 38586196 PMCID: PMC10996447 DOI: 10.3389/fnins.2024.1337739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 03/04/2024] [Indexed: 04/09/2024] Open
Abstract
Background Anxiety and depression are prevalent mental disorders. As modern society continues to face mounting pressures, the incidence of anxiety and depression is on the rise. In recent years, there has been an increasing breadth of research exploring the relationship between anxiety, depression, and physical activity (PA). However, the current research progress and future development trends are unclear. The purpose of this study is to explore the research hotspots and development trends in this field, and to provide guidance for future studies and to provide some reference for clinicians. Methods We searched the relevant literature of Web of Science Core Collection from the establishment of the database to August 15, 2023. CiteSpace, VOSviewer and Bibliometrix Packages based on the R language were used to analyze the number of publications, countries, institutions, journals, authors, references, and keywords. Results A total of 1,591 studies were included in the analysis, and the research in the field of PA on anxiety or depression has consistently expanded. The USA (304 publications), Harvard University (93 publications), and the journal of affective disorders (97 publications) were the countries, institutions, and journals that published the highest number of articles, respectively. According to the keywords, students and pregnant women, adult neurogenesis, and Tai Chi were the groups of concern, physiological and pathological mechanisms, and the type of PA of interest, respectively. Conclusion The study of PA on anxiety or depression is experiencing ongoing expansion. Clinicians can consider advising patients to take mind-body exercise to improve mood. In addition, future researchers can explore the mind-body exercise and its impact on anxiety or depression, PA and anxiety or depression in specific populations, and adult neurogenesis of various exercise in anxiety or depression.
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Affiliation(s)
- Xin-Yue Zhang
- School of Acu-Mox and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Acupuncture Clinical Research Center of Sichuan Province, Chengdu, China
| | - Fang Ye
- Department of Neurology, The Sichuan Province People's Hospital, Chengdu, China
| | - Zi-Han Yin
- School of Acu-Mox and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Acupuncture Clinical Research Center of Sichuan Province, Chengdu, China
| | - Ya-Qin Li
- School of Acu-Mox and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Acupuncture Clinical Research Center of Sichuan Province, Chengdu, China
| | - Qiong-Nan Bao
- School of Acu-Mox and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Acupuncture Clinical Research Center of Sichuan Province, Chengdu, China
| | - Man-Ze Xia
- School of Acu-Mox and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Acupuncture Clinical Research Center of Sichuan Province, Chengdu, China
| | - Zheng-Hong Chen
- School of Acu-Mox and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Acupuncture Clinical Research Center of Sichuan Province, Chengdu, China
| | - Wan-Qi Zhong
- School of Acu-Mox and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Acupuncture Clinical Research Center of Sichuan Province, Chengdu, China
| | - Ke-Xin Wu
- School of Acu-Mox and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Acupuncture Clinical Research Center of Sichuan Province, Chengdu, China
| | - Jin Yao
- School of Acu-Mox and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Acupuncture Clinical Research Center of Sichuan Province, Chengdu, China
| | - Fan-Rong Liang
- School of Acu-Mox and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
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3
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Collins HM, Pinacho R, Ozdemir D, Bannerman DM, Sharp T. Effect of selective serotonin reuptake inhibitor discontinuation on anxiety-like behaviours in mice. J Psychopharmacol 2022; 36:794-805. [PMID: 35607713 PMCID: PMC9247435 DOI: 10.1177/02698811221093032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Abrupt cessation of therapy with a selective serotonin reuptake inhibitor (SSRI) is associated with a discontinuation syndrome, typified by numerous disabling symptoms, including anxiety. Surprisingly, little is known of the behavioural effect of SSRI discontinuation in animals. AIM Here, the effect of SSRI discontinuation on anxiety-like behaviour was systematically investigated in mice. METHODS Experiments were based on a three-arm experimental design comprising saline, continued SSRI and discontinued SSRI. Mice were assessed 2 days after SSRI discontinuation over a 5-day period using the elevated plus maze (EPM) and other anxiety tests. RESULTS An exploratory experiment found cessation of paroxetine (12 days) was associated with decreased open-arm exploration and reduced total distance travelled, in male but not female mice. Follow-up studies confirmed a discontinuation effect on the EPM in male mice after paroxetine (12 days) and also citalopram (12 days). Mice receiving continued paroxetine (but not citalopram) also showed decreased open-arm exploration but this was dissociable from the effects of discontinuation. The discontinuation response to paroxetine did not strengthen after 28 days of treatment but was absent after 7 days of treatment. A discontinuation response was not discernible in other anxiety and fear-learning tests applied 3-5 days after treatment cessation. Finally, discontinuation effects on the EPM were typically associated with decreased locomotion on the test. However, separate locomotor testing implicated anxiety-provoked behavioural inhibition rather than a general reduction in motor activity. CONCLUSION Overall, this study provides evidence for a short-lasting behavioural discontinuation response to cessation of SSRI treatment in mice.
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Affiliation(s)
- Helen M Collins
- Department of Pharmacology,
University of Oxford, Oxford, UK,Department of Experimental
Psychology, University of Oxford, Oxford, UK
| | - Raquel Pinacho
- Department of Pharmacology,
University of Oxford, Oxford, UK,Department of Experimental
Psychology, University of Oxford, Oxford, UK
| | - Dersu Ozdemir
- Department of Pharmacology,
University of Oxford, Oxford, UK
| | - David M Bannerman
- Department of Experimental
Psychology, University of Oxford, Oxford, UK
| | - Trevor Sharp
- Department of Pharmacology,
University of Oxford, Oxford, UK,Trevor Sharp, Department of
Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT,
UK.
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Trzeciak P, Herbet M. Role of the Intestinal Microbiome, Intestinal Barrier and Psychobiotics in Depression. Nutrients 2021; 13:927. [PMID: 33809367 PMCID: PMC8000572 DOI: 10.3390/nu13030927] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/07/2021] [Accepted: 03/08/2021] [Indexed: 12/18/2022] Open
Abstract
The intestinal microbiota plays an important role in the pathophysiology of depression. As determined, the microbiota influences the shaping and modulation of the functioning of the gut-brain axis. The intestinal microbiota has a significant impact on processes related to neurotransmitter synthesis, the myelination of neurons in the prefrontal cortex, and is also involved in the development of the amygdala and hippocampus. Intestinal bacteria are also a source of vitamins, the deficiency of which is believed to be related to the response to antidepressant therapy and may lead to exacerbation of depressive symptoms. Additionally, it is known that, in periods of excessive activation of stress reactions, the immune system also plays an important role, negatively affecting the tightness of the intestinal barrier and intestinal microflora. In this review, we have summarized the role of the gut microbiota, its metabolites, and diet in susceptibility to depression. We also describe abnormalities in the functioning of the intestinal barrier caused by increased activity of the immune system in response to stressors. Moreover, the presented study discusses the role of psychobiotics in the prevention and treatment of depression through their influence on the intestinal barrier, immune processes, and functioning of the nervous system.
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Affiliation(s)
| | - Mariola Herbet
- Chair and Department of Toxicology, Faculty of Pharmacy, Medical University of Lublin, Jaczewskiego 8b Street, 20-090 Lublin, Poland;
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Portal B, Delcourte S, Rovera R, Lejards C, Bullich S, Malnou CE, Haddjeri N, Déglon N, Guiard BP. Genetic and pharmacological inactivation of astroglial connexin 43 differentially influences the acute response of antidepressant and anxiolytic drugs. Acta Physiol (Oxf) 2020; 229:e13440. [PMID: 31925934 DOI: 10.1111/apha.13440] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 12/18/2019] [Accepted: 01/02/2020] [Indexed: 12/12/2022]
Abstract
AIM Astroglial connexins (Cxs) 30 and 43 are engaged in gap junction and hemichannel activities. Evidence suggests that these functional entities contribute to regulating neurotransmission, thereby influencing brain functions. In particular, preclinical and clinical findings highlight a role of Cx43 in animal models of depression. However, the role of these proteins in response to currently available psychotropic drugs is still unknown. METHODS To investigate this, we evaluated the behavioural effects of the genetic and pharmacological inactivation of Cx43 on the antidepressant- and anxiolytic-like activities of the selective serotonin reuptake inhibitor fluoxetine and the benzodiazepine diazepam, respectively. RESULTS A single administration of fluoxetine (18 mg/kg; i.p.) produced a higher increase in hippocampal extracellular serotonin levels, and a greater antidepressant-like effect in the tail suspension test in Cx43 knock-down (KD) mice bred on a C57BL/6 background compared to their wild-type littermates. Similarly, in outbred Swiss wild-type mice, the intra-hippocampal injection of a shRNA-Cx43 or the acute systemic injection of the Cxs inhibitor carbenoxolone (CBX: 10 mg/kg; i.p.) potentiated the antidepressant-like effects of fluoxetine. Evaluating the effects of such strategies on diazepam (0.5 mg/kg; i.p.), the results indicate that Cx43 KD mice or wild-types injected with a shRNA-Cx43 in the amygdala, but not in the hippocampus, attenuated the anxiolytic-like effects of this benzodiazepine in the elevated plus maze. The chronic systemic administration of CBX mimicked the latter observations. CONCLUSION Collectively, these data pave the way to the development of potentiating strategies in the field of psychiatry based on the modulation of astroglial Cx43.
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Affiliation(s)
- Benjamin Portal
- Centre de Recherches sur la Cognition Animale (CRCA) Centre de Biologie Intégrative (CBI) Université Paul Sabatier Toulouse III Toulouse France
| | - Sarah Delcourte
- Univ Lyon Université Claude Bernard Lyon 1 Inserm Stem Cell and Brain Research Institute U1208 Bron France
| | - Renaud Rovera
- Univ Lyon Université Claude Bernard Lyon 1 Inserm Stem Cell and Brain Research Institute U1208 Bron France
| | - Camille Lejards
- Centre de Recherches sur la Cognition Animale (CRCA) Centre de Biologie Intégrative (CBI) Université Paul Sabatier Toulouse III Toulouse France
| | - Sebastien Bullich
- Centre de Recherches sur la Cognition Animale (CRCA) Centre de Biologie Intégrative (CBI) Université Paul Sabatier Toulouse III Toulouse France
| | - Cécile E. Malnou
- Centre de Physiopathologie Toulouse‐Purpan (CPTP) INSERM CNRS Université de Toulouse Toulouse France
| | - Nasser Haddjeri
- Univ Lyon Université Claude Bernard Lyon 1 Inserm Stem Cell and Brain Research Institute U1208 Bron France
| | - Nicole Déglon
- Department of Clinical Neurosciences Laboratory of Neurotherapies and Neuromodulation (LNTM) Lausanne University Hospital Lausanne Switzerland
- Neuroscience Research Center LNTM Lausanne University Hospital Lausanne Switzerland
| | - Bruno P. Guiard
- Centre de Recherches sur la Cognition Animale (CRCA) Centre de Biologie Intégrative (CBI) Université Paul Sabatier Toulouse III Toulouse France
- Faculté de Pharmacie Université Paris Sud Université Paris‐Saclay Chatenay‐Malabry France
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6
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Garro-Martínez E, Vidal R, Adell A, Díaz Á, Castro E, Amigó J, Gutiérrez-Lanza R, Florensa-Zanuy E, Gómez-Acero L, Taketo MM, Pazos Á, Pilar-Cuéllar F. β-Catenin Role in the Vulnerability/Resilience to Stress-Related Disorders Is Associated to Changes in the Serotonergic System. Mol Neurobiol 2019; 57:1704-1715. [DOI: 10.1007/s12035-019-01841-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 11/22/2019] [Indexed: 01/02/2023]
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7
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Muscular and mitochondrial effects of long-term fluoxetine treatment in mice, combined with physical endurance exercise on treadmill. Life Sci 2019; 232:116508. [DOI: 10.1016/j.lfs.2019.05.064] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 05/22/2019] [Accepted: 05/23/2019] [Indexed: 01/11/2023]
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8
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Der-Ghazarian TS, Charmchi D, Noudali SN, Scott SN, Holter MC, Newbern JM, Neisewander JL. Neural Circuits Associated with 5-HT 1B Receptor Agonist Inhibition of Methamphetamine Seeking in the Conditioned Place Preference Model. ACS Chem Neurosci 2019; 10:3271-3283. [PMID: 31042352 DOI: 10.1021/acschemneuro.8b00709] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
5-HT1B receptors (5-HT1BRs) modulate psychostimulant reward and incentive motivation in rodents. Here we investigated the effects of the 5-HT1BR agonist CP94253 (10 mg/kg, IP) on the acquisition and expression of methamphetamine (Meth) conditioned place preference (CPP) in C57BL/6 male mice. We subsequently examined the potential brain regions involved in CP94253 effects using FOS as a marker of neural activity. In the acquisition experiment, mice received the agonist 30 min before each of the Meth injections given during conditioning. In the expression experiment, mice that had acquired Meth-CPP were given either saline or CP94253 and were tested for CPP 30 min later. We found that CP94253 attenuated the expression of Meth-CPP, but had no effect on acquisition. Mice expressing Meth-CPP had elevated numbers of FOS+ cells in the ventral tegmental area (VTA) and basolateral amygdala (BlA) and reduced FOS+ cells in the central amygdala (CeA) compared to saline controls. CP94253 given before the expression test, but not acutely in drug-naive mice, enhanced FOS+ cells in the VTA, the nucleus accumbens (NAc) shell and core, and the dorsomedial striatum and reversed the Meth-conditioned changes in FOS in the BlA and CeA. Approximately 50-70% of FOS+ cells in the NAc and VTA were GABAergic regardless of group. By contrast, we did not observe FOS-labeling in dopamine neurons in the VTA. The findings suggest that CP94253 attenuates the motivational effects of the Meth-associated environment and highlight the amygdala, VTA, NAc, and dorsomedial striatum as potential regions involved in this effect.
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Affiliation(s)
| | - Delaram Charmchi
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287, United States
| | - Sean N. Noudali
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287, United States
| | - Samantha N. Scott
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287, United States
| | - Michael C. Holter
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287, United States
| | - Jason M. Newbern
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287, United States
| | - Janet L. Neisewander
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287, United States
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9
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Pham TH, Gardier AM. Fast-acting antidepressant activity of ketamine: highlights on brain serotonin, glutamate, and GABA neurotransmission in preclinical studies. Pharmacol Ther 2019; 199:58-90. [DOI: 10.1016/j.pharmthera.2019.02.017] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 02/25/2019] [Indexed: 12/13/2022]
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10
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Vilela-Costa HH, Spiacci A, Bissolli IG, Zangrossi H. A Shift in the Activation of Serotonergic and Non-serotonergic Neurons in the Dorsal Raphe Lateral Wings Subnucleus Underlies the Panicolytic-Like Effect of Fluoxetine in Rats. Mol Neurobiol 2019; 56:6487-6500. [DOI: 10.1007/s12035-019-1536-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 02/22/2019] [Indexed: 01/04/2023]
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11
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Blanchard D, Meyza K. Risk assessment and serotonin: Animal models and human psychopathologies. Behav Brain Res 2019; 357-358:9-17. [DOI: 10.1016/j.bbr.2017.07.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 05/19/2017] [Accepted: 07/07/2017] [Indexed: 02/08/2023]
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12
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Quentin E, Belmer A, Maroteaux L. Somato-Dendritic Regulation of Raphe Serotonin Neurons; A Key to Antidepressant Action. Front Neurosci 2018; 12:982. [PMID: 30618598 PMCID: PMC6307465 DOI: 10.3389/fnins.2018.00982] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 12/07/2018] [Indexed: 11/22/2022] Open
Abstract
Several lines of evidence implicate serotonin (5-hydroxytryptamine, 5-HT)in regulating personality traits and mood control. Serotonergic neurons are classically thought to be tonic regular-firing, “clock-like” neurons. Neurotransmission by serotonin is tightly regulated by the serotonin transporter (SERT) and by autoreceptors (serotonin receptors expressed by serotonin neurons) through negative feedback inhibition at the cell bodies and dendrites (5-HT1A receptors) of the dorsal raphe nuclei or at the axon terminals (5-HT1B receptors). In dorsal raphe neurons, the release of serotonin from vesicles in the soma, dendrites, and/or axonal varicosities is independent of classical synapses and can be induced by neuron depolarization, by the stimulation of L-type calcium channels, by activation of glutamatergic receptors, and/or by activation of 5-HT2 receptors. The resulting serotonin release displays a slow kinetic and a large diffusion. This process called volume transmission may ultimately affect the rate of discharge of serotonergic neurons, and their tonic activity. The therapeutic effects induced by serotonin-selective reuptake inhibitor (SSRI) antidepressants are initially triggered by blocking SERT but rely on consequences of chronic exposure, i.e., a selective desensitization of somatodendritic 5-HT1A autoreceptors. Agonist stimulation of 5-HT2B receptors mimicked behavioral and neurogenic SSRI actions, and increased extracellular serotonin in dorsal raphe. By contrast, a lack of effects of SSRIs was observed in the absence of 5-HT2B receptors (knockout-KO), even restricted to serotonergic neurons (Htr2b5-HTKO mice). The absence of 5-HT2B receptors in serotonergic neurons is associated with a higher 5-HT1A-autoreceptor reactivity and thus a lower firing activity of these neurons. In agreement, mice with overexpression of 5-HT1A autoreceptor show decreased neuronal activity and increased depression-like behavior that is resistant to SSRI treatment. We propose thus that the serotonergic tone results from the opposite control exerted by somatodendritic (Gi-coupled) 5-HT1A and (Gq-coupled) 5-HT2B receptors on dorsal raphe neurons. Therefore, 5-HT2B receptors may contribute to SSRI therapeutic effects by their positive regulation of adult raphe serotonergic neurons. Deciphering the molecular mechanism controlling extrasynaptic release of serotonin, and how autoreceptors interact in regulating the tonic activity of serotonergic neurons, is critical to fully understand the therapeutic effect of SSRIs.
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Affiliation(s)
- Emily Quentin
- INSERM UMR-S 839, Institut du Fer à Moulin, Paris, France.,Sorbonne Universités, UPMC University Paris 6, Paris, France.,Institut du Fer à Moulin, Paris, France
| | - Arnauld Belmer
- INSERM UMR-S 839, Institut du Fer à Moulin, Paris, France.,Sorbonne Universités, UPMC University Paris 6, Paris, France.,Institut du Fer à Moulin, Paris, France
| | - Luc Maroteaux
- INSERM UMR-S 839, Institut du Fer à Moulin, Paris, France.,Sorbonne Universités, UPMC University Paris 6, Paris, France.,Institut du Fer à Moulin, Paris, France
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13
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Mendez-David I, Guilloux JP, Papp M, Tritschler L, Mocaer E, Gardier AM, Bretin S, David DJ. S 47445 Produces Antidepressant- and Anxiolytic-Like Effects through Neurogenesis Dependent and Independent Mechanisms. Front Pharmacol 2017; 8:462. [PMID: 28769796 PMCID: PMC5515821 DOI: 10.3389/fphar.2017.00462] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 06/28/2017] [Indexed: 12/20/2022] Open
Abstract
Glutamatergic dysfunctions are observed in the pathophysiology of depression. The glutamatergic synapse as well as the AMPA receptor’s (AMPAR) activation may represent new potential targets for therapeutic intervention in the context of major depressive disorders. S 47445 is a novel AMPARs positive allosteric modulator (AMPA-PAM) possessing procognitive, neurotrophic properties and enhancing synaptic plasticity. Here, we investigated the antidepressant/anxiolytic-like effects of S 47445 in a mouse model of anxiety/depression based on chronic corticosterone administration (CORT) and in the Chronic Mild Stress (CMS) model in rats. Four doses of S 47445 (0.3 to 10 mg/kg, oral route, 4 and 5 weeks, respectively) were assessed in both models. In mouse, behavioral effects were tested in various anxiety-and depression-related behaviors : the elevated plus maze (EPM), open field (OF), splash test (ST), forced swim test (FST), tail suspension test (TST), fur coat state and novelty suppressed feeding (NSF) as well as on hippocampal neurogenesis and dendritic arborization in comparison to chronic fluoxetine treatment (18 mg/kg, p.o.). In rats, behavioral effects of S 47445 were monitored using sucrose consumption and compared to those of imipramine or venlafaxine (10 mg/kg, i.p.) during the whole treatment period and after withdrawal of treatments. In a mouse model of genetic ablation of hippocampal neurogenesis (GFAP-Tk model), neurogenesis dependent/independent effects of chronic S 47445 treatment were tested, as well as BDNF hippocampal expression. S 47445 reversed CORT-induced depressive-like state by increasing grooming duration and reversing coat state’s deterioration. S 47445 also decreased the immobility duration in TST and FST. The highest doses (3 and 10 mg/kg) seem the most effective for antidepressant-like activity in CORT mice. Furthermore, S 47445 significantly reversed the anxiety phenotype observed in OF (at 1 mg/kg) and EPM (from 1 mg/kg). In the CMS rat model, S 47445 (from 1 mg/kg) demonstrated a rapid onset of effect on anhedonia compared to venlafaxine and imipramine. In the CORT model, S 47445 demonstrated significant neurogenic effects on proliferation, survival and maturation of hippocampal newborn neurons at doses inducing an antidepressant-like effect. It also corrected CORT-induced deficits of growth and arborization of dendrites. Finally, the antidepressant/anxiolytic-like activities of S 47445 required adult hippocampal neurogenesis in the novelty suppressed feeding test contrary to OF, EPM and ST. The observed increase in hippocampal BDNF levels could be one of the mechanisms of S 47445 responsible for the adult hippocampal neurogenesis increase. Altogether, S 47445 displays robust antidepressant-anxiolytic-like properties after chronic administration through neurogenesis dependent/independent mechanisms and neuroplastic activities. The AMPA-PAM S 47445 could have promising therapeutic potential for the treatment of major depressive disorders or generalized anxiety disorders.
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Affiliation(s)
- Indira Mendez-David
- CESP/UMRS-1178, Faculté de Pharmacie, Institut National de la Santé et de la Recherche Médicale, Université Paris-Sud - Université Paris-SaclayChatenay-Malabry, France
| | - Jean-Philippe Guilloux
- CESP/UMRS-1178, Faculté de Pharmacie, Institut National de la Santé et de la Recherche Médicale, Université Paris-Sud - Université Paris-SaclayChatenay-Malabry, France
| | - Mariusz Papp
- Institute of Pharmacology, Polish Academy of SciencesKrakow, Poland
| | - Laurent Tritschler
- CESP/UMRS-1178, Faculté de Pharmacie, Institut National de la Santé et de la Recherche Médicale, Université Paris-Sud - Université Paris-SaclayChatenay-Malabry, France
| | | | - Alain M Gardier
- CESP/UMRS-1178, Faculté de Pharmacie, Institut National de la Santé et de la Recherche Médicale, Université Paris-Sud - Université Paris-SaclayChatenay-Malabry, France
| | - Sylvie Bretin
- Institut de Recherches Internationales ServierSuresnes, France
| | - Denis J David
- CESP/UMRS-1178, Faculté de Pharmacie, Institut National de la Santé et de la Recherche Médicale, Université Paris-Sud - Université Paris-SaclayChatenay-Malabry, France
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Modified Suanzaorentang Had the Treatment Effect for Generalized Anxiety Disorder for the First 4 Weeks of Paroxetine Medication: A Pragmatic Randomized Controlled Study. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2017; 2017:8391637. [PMID: 28553362 PMCID: PMC5434311 DOI: 10.1155/2017/8391637] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 03/17/2017] [Accepted: 04/06/2017] [Indexed: 12/13/2022]
Abstract
Background. Paroxetine does not show satisfactory therapeutic effect for generalized anxiety disorder (GAD) patients for the first 2–4 weeks of medication. Diazepam is always concurrently used although it has some shortcomings such as physical dependence and withdrawal reactions. In this study, we aimed to identify whether modified Suanzaorentang (MSZRT), a combined Chinese formula including Suanzaorentang (SZRT) and Zhizichitang (ZZCT), could control the anxiety of GAD for the first 4 weeks of paroxetine medication. Methods. 156 GAD patients were randomized to the treatment of paroxetine, paroxetine-diazepam, or paroxetine-MSZRT for 4 weeks. Hamilton Anxiety Scale (HAMA) Test and Self-Rating Anxiety Scale (SAS) Test were determined each week as the evaluation of clinical efficacy. Adverse events (AEs) were also closely observed by performing the Treatment Emergent Symptom Scale (TESS) Test. Results. Both paroxetine-MSZRT and paroxetine-diazepam decreased more HAMA and SAS total scores than paroxetine from weeks 1 to 3. Paroxetine-MSZRT as well as paroxetine-diazepam had an obviously higher onset rate than paroxetine in each week. After 4 weeks' treatment, the overall effectiveness rate in the paroxetine-MSZRT group (90.00%) was obviously higher than those of the paroxetine group (74.42%) but did not significantly differ from the paroxetine-diazepam group (93.88%). Conclusion. MSZRT had the treatment effect for GAD when paroxetine was used for the first 4 weeks.
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Brockway ET, Krater KR, Selva JA, Wauson SER, Currie PJ. Impact of [d-Lys(3)]-GHRP-6 and feeding status on hypothalamic ghrelin-induced stress activation. Peptides 2016; 79:95-102. [PMID: 27020248 DOI: 10.1016/j.peptides.2016.03.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 03/20/2016] [Accepted: 03/23/2016] [Indexed: 12/18/2022]
Abstract
Ghrelin administration directly into hypothalamic nuclei, including the arcuate nucleus (ArcN) and the paraventricular nucleus (PVN), alters the expression of stress-related behaviors. In the present study we investigated the effect of feeding status on the ability of ghrelin to induce stress and anxiogenesis. Adult male Sprague Dawley rats were implanted with guide cannula targeting either the ArcN or PVN. In the first experiment we confirmed that ArcN and PVN ghrelin treatment produced anxiety-like behavior as measured using the elevated plus maze (EPM) paradigm. Ghrelin was administered during the early dark cycle. Immediately after microinjections rats were placed in the EPM for 5min. Both ArcN and PVN treatment reduced open arm exploration. The effect was attenuated by pretreatment with the ghrelin 1a receptor antagonist [d-Lys(3)]-GHRP-6. In a separate group of animals ghrelin was injected into either nucleus and rats were returned to their home cages for 60min with free access to food. An additional group of rats was returned to home cages with no food access. After 60min with or without food access all rats were tested in the EPM. Results indicated that food consumption just prior to EPM testing reversed the avoidance of the open arms of the EPM. In contrast, rats injected with ghrelin, placed in their home cage for 60min without food, and subsequently tested in the EPM, exhibited an increased avoidance of the open arms, consistent with stress activation. Overall, our findings demonstrate that ghrelin 1a receptor blockade and feeding status appear to impact the ability of ArcN and PVN ghrelin to elicit stress and anxiety-like behaviors.
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Affiliation(s)
- Emma T Brockway
- Department of Psychology, Reed College, Portland, OR 97202, United States
| | - Katherine R Krater
- Department of Psychology, Reed College, Portland, OR 97202, United States
| | - Joaquín A Selva
- Department of Psychology, Reed College, Portland, OR 97202, United States
| | - Shelby E R Wauson
- Department of Psychology, Reed College, Portland, OR 97202, United States
| | - Paul J Currie
- Department of Psychology, Reed College, Portland, OR 97202, United States.
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Treatment-resistant depression: are animal models of depression fit for purpose? Psychopharmacology (Berl) 2015; 232:3473-95. [PMID: 26289353 DOI: 10.1007/s00213-015-4034-7] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 07/20/2015] [Indexed: 12/13/2022]
Abstract
BACKGROUND Resistance to antidepressant drug treatment remains a major health problem. Animal models of depression are efficient in detecting effective treatments but have done little to increase the reach of antidepressant drugs. This may be because most animal models of depression target the reversal of stress-induced behavioural change, whereas treatment-resistant depression is typically associated with risk factors that predispose to the precipitation of depressive episodes by relatively low levels of stress. Therefore, the search for treatments for resistant depression may require models that incorporate predisposing factors leading to heightened stress responsiveness. METHOD Using a diathesis-stress framework, we review developmental, genetic and genomic models against four criteria: (i) increased sensitivity to stress precipitation of a depressive behavioural phenotype, (ii) resistance to chronic treatment with conventional antidepressants, (iii) a good response to novel modes of antidepressant treatment (e.g. ketamine; deep brain stimulation) that are reported to be effective in treatment-resistant depression and (iv) a parallel to a known clinical risk factor. RESULTS We identify 18 models that may have some potential. All require further validation. Currently, the most promising are the Wistar-Kyoto (WKY) and congenital learned helplessness (cLH) rat strains, the high anxiety behaviour (HAB) mouse strain and the CB1 receptor knockout and OCT2 null mutant mouse strains. CONCLUSION Further development is needed to validate models of antidepressant resistance that are fit for purpose. The criteria used in this review may provide a helpful framework to guide research in this area.
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Wauson SER, Sarkodie K, Schuette LM, Currie PJ. Midbrain raphe 5-HT1A receptor activation alters the effects of ghrelin on appetite and performance in the elevated plus maze. J Psychopharmacol 2015; 29:836-44. [PMID: 25922422 DOI: 10.1177/0269881115581981] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Prior research suggests that midbrain serotonergic signaling and hypothalamic ghrelinergic signaling both play critical roles in appetitive and emotional behaviors. In the present study, we investigated the effects of median raphe nucleus (MRN) somatodentritic 5-HT1A receptor activation on the feeding-stimulant and anxiogenic action of paraventricular nucleus (PVN) ghrelin. In an initial experiment, adult male Sprague-Dawley rats were injected with either ghrelin (200-800 pmol) into the PVN or 8-OH-DPAT (2.5-10 nmol), a 5-HT1A receptor agonist, into the MRN. Performance on the elevated plus maze (EPM) was then assessed. In separate rats, MRN 8-OH-DPAT (2.5-5 nmol) was administered 5 min prior to PVN injection of ghrelin (400 pmol) followed by EPM testing. The orexigenic effects of MRN 8-OH-DPAT (0.1-1.6 nmol) paired with PVN ghrelin (50 pmol) were also examined. When administered alone into the PVN, ghrelin significantly decreased the number of entries and time spent in the open arms of the EPM. This anxiogenic effect was blocked if rats were allowed to eat immediately after ghrelin administration and then tested in the plus maze. MRN injections of 8-OH-DPAT were anxiolytic, and when rats were pretreated with 8-OH-DPAT prior to ghrelin, the anxiogenic action of the peptide was attenuated. In contrast, MRN administration of 8-OH-DPAT potentiated the eating-stimulant effect of PVN ghrelin. Overall, our findings demonstrate that ghrelinergic and serotonergic circuits interact in the neural control of eating and anxiety-like behaviors, with 5-HT1A receptor mechanisms potentiating the orexigenic action of ghrelin while inhibiting ghrelin-induced anxiogenesis as measured via the EPM.
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Affiliation(s)
| | - Kwaku Sarkodie
- Department of Psychology, Reed College, Portland, OR, USA
| | | | - Paul J Currie
- Department of Psychology, Reed College, Portland, OR, USA
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Liu Y, Kelly MA, Sexton TJ, Neumaier JF. 5-HT1B autoreceptors differentially modulate the expression of conditioned fear in a circuit-specific manner. Neuroscience 2015; 298:436-47. [PMID: 25907441 DOI: 10.1016/j.neuroscience.2015.04.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 04/08/2015] [Accepted: 04/13/2015] [Indexed: 12/17/2022]
Abstract
Located in the nerve terminals of serotonergic neurons, 5-HT1B autoreceptors are poised to modulate synaptic 5-HT levels with precise temporal and spatial control, and play an important role in various emotional behaviors. This study characterized two novel, complementary viral vector strategies to investigate the contribution of 5-HT1B autoreceptors to fear expression, displayed as freezing, during contextual fear conditioning. Increased expression of 5-HT1B autoreceptors throughout the brain significantly decreased fear expression in both wild-type (WT) and 5-HT1B knockout (1BKO) mice when receptor levels were increased with a cell-type-specific herpes simplex virus (HSV) vector injected into the dorsal raphe nucleus (DRN). Additional studies used an intersectional viral vector strategy, in which an adeno-associated virus containing a double-floxed inverted sequence for the 5-HT1B receptor (AAV-DIO-1B) was combined with the retrogradely transported canine adenovirus-2 expressing Cre (CAV-Cre) in order to increase 5-HT1B autoreceptor expression only in neurons projecting from the DRN to the amygdala. Surprisingly, selective expression of 5-HT1B autoreceptors in just this circuit led to an increase in fear expression in WT, but not 1BKO, mice. These results suggest that activation of 5-HT1B autoreceptors throughout the brain may have an overall effect of attenuating fear expression, but activation of subsets of 5-HT1B autoreceptors in particular brain regions, reflecting distinct projections of serotonergic neurons from the DRN, may have disparate contributions to the ultimate response.
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Affiliation(s)
- Y Liu
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA.
| | - M A Kelly
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA.
| | - T J Sexton
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA.
| | - J F Neumaier
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA.
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Dinel AL, Joffre C, Trifilieff P, Aubert A, Foury A, Le Ruyet P, Layé S. Inflammation early in life is a vulnerability factor for emotional behavior at adolescence and for lipopolysaccharide-induced spatial memory and neurogenesis alteration at adulthood. J Neuroinflammation 2014; 11:155. [PMID: 25224537 PMCID: PMC4172903 DOI: 10.1186/s12974-014-0155-x] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 08/21/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The postnatal period is a critical time window during which inflammatory events have significant and enduring effects on the brain, and as a consequence, induce alterations of emotional behavior and/or cognition later in life. However, the long-term effect of neonatal inflammation on behavior during adolescence, a sensitive period for the development of neurodevelopmental psychiatric disorders, has been little studied. In this study, we examined whether an early-life inflammatory challenge could alter emotional behaviors and spatial memory at adolescence and adulthood and whether stress axis activity, inflammatory response and neurogenesis were affected. METHODS Lipopolysaccharide (LPS, 100 μg/kg) was administered to mice on postnatal day (PND) 14 and cytokine expression was measured in the plasma and in brain structures 3 hours later. Anxiety-like and depressive-like behavior (measured in the novelty-suppressed feeding test and the forced swim test, respectively) and spatial memory (Y-maze test) were measured at adolescence (PND30) and adulthood (PND90). Hypothalamic-pituitary-adrenal (HPA) axis activity (plasma corticosterone and glucocorticoid receptors in the hippocampus and prefrontal cortex) was measured at adulthood. In addition, the impact of a novel adult LPS challenge (100 μ/kg) was measured on spatial memory (Y-maze test), neurogenesis (doublecortin-positive cell numbers in the hippocampus) and plasma cytokine expression. RESULTS First, we show in PND14 pups that a peripheral administration of LPS induced the expression of pro- and anti-inflammatory cytokines in the plasma and brain structures that were studied 3 hours after administration. Anxiety-like behavior was altered in adolescent, but not in adult, mice, whereas depressive-like behavior was spared at adolescence and increased at adulthood. This was accompanied by a decreased phosphorylation of the glucocorticoid receptor in the prefrontal cortex, with no effect on corticosterone levels. Second, neonatal LPS treatment had no effect on spatial memory in adolescence and adulthood. However, a second challenge of LPS in adulthood impaired spatial memory performance and neurogenesis and increased circulating levels of CCL2. CONCLUSIONS Our study shows for the first time, in mice, that a peripheral LPS treatment at PND14 differentially alters emotional behaviors, but not spatial memory, at adolescence and adulthood. The behavioral effect of LPS at PND14 could be attributed to HPA axis deregulation and neurogenesis impairment.
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Islam M, Moriguchi S, Tagashira H, Fukunaga K. Rivastigmine improves hippocampal neurogenesis and depression-like behaviors via 5-HT1A receptor stimulation in olfactory bulbectomized mice. Neuroscience 2014; 272:116-30. [DOI: 10.1016/j.neuroscience.2014.04.046] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 04/23/2014] [Accepted: 04/23/2014] [Indexed: 11/29/2022]
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Beaudoin-Gobert M, Sgambato-Faure V. Serotonergic pharmacology in animal models: from behavioral disorders to dyskinesia. Neuropharmacology 2014; 81:15-30. [PMID: 24486710 DOI: 10.1016/j.neuropharm.2014.01.031] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2013] [Revised: 01/19/2014] [Accepted: 01/20/2014] [Indexed: 02/04/2023]
Abstract
Serotonin (5-HT) dysfunction has been involved in both movement and behavioral disorders. Serotonin pharmacology improves dyskinetic movements as well as depressive, anxious, aggressive and anorexic symptoms. Animal models have been useful to investigate more precisely to what extent 5-HT is involved and whether drugs targeting the 5-HT system can counteract the symptoms exhibited. We review existing rodent and non-human primate (NHP) animal models in which selective 5-HT or dual 5-HT-norepinephrine (NE) transporter inhibitors, as well as specific 5-HT receptors agonists and antagonists, monoamine oxidase A inhibitors (IMAO-A) and MDMA (Ecstasy) have been used. We review overlaps between the various drug classes involved. We confront behavioral paradigms and treatment regimen. Some but not all animal models and associated pharmacological treatments have been extensively studied in the litterature. In particular, the impact of selective serotonin reuptake inhibitors (SSRI) has been extensively investigated using a variety of pharmacological or genetic rodent models of depression, anxiety, aggressiveness. But the validity of these rodent models is questioned. On the contrary, few studies did address the potential impact of targeting the 5-HT system on NHP models of behavioral disorders, despite the fact that those models may match more closely to human pathologies. Further investigations with carefull behavioral analysis will improve our understanding of neural bases underlying the pathophysiology of movement and behavioral disorders.
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Affiliation(s)
- Maude Beaudoin-Gobert
- Centre de Neuroscience Cognitive, Centre National de la Recherche Scientifique UMR 5229, Bron cedex F-69675, France; Université Lyon 1, France
| | - Véronique Sgambato-Faure
- Centre de Neuroscience Cognitive, Centre National de la Recherche Scientifique UMR 5229, Bron cedex F-69675, France; Université Lyon 1, France.
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Akutagava-Martins GC, Salatino-Oliveira A, Kieling CC, Rohde LA, Hutz MH. Genetics of attention-deficit/hyperactivity disorder: current findings and future directions. Expert Rev Neurother 2014; 13:435-45. [DOI: 10.1586/ern.13.30] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Mahableshwarkar AR, Jacobsen PL, Chen Y, Simon JS. A randomised, double-blind, placebo-controlled, duloxetine-referenced study of the efficacy and tolerability of vortioxetine in the acute treatment of adults with generalised anxiety disorder. Int J Clin Pract 2014; 68:49-59. [PMID: 24341301 DOI: 10.1111/ijcp.12328] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 09/12/2013] [Accepted: 09/16/2013] [Indexed: 01/04/2023] Open
Abstract
AIMS This study aims to evaluate the efficacy and tolerability of vortioxetine 2.5-, 5- and 10-mg once-daily doses vs. placebo in the treatment of generalised anxiety disorder (GAD). METHODS In this 8-week, multicentre, double-blind, placebo-controlled, parallel-group, phase 3 study, patients with a primary GAD diagnosis were randomised to receive placebo (n = 157), vortioxetine 2.5 mg, vortioxetine 5 mg, vortioxetine 10 mg or duloxetine 60 mg once daily (n = 156 each). The primary end-point, mean change from baseline in Hamilton Anxiety Scale (HAM-A) total score and key secondary end-points for the 5- and 10-mg vortioxetine doses were analysed in a prespecified sequential testing procedure (all at week 8). Sexual dysfunction was evaluated using the Arizona Sexual Experiences Scale. RESULTS Differences from placebo in the primary efficacy end-point were not statistically significant for the vortioxetine groups. The mean difference from placebo was significant in the duloxetine arm. For all secondary efficacy end-points, results were similar among the vortioxetine groups and did not reach statistical significance. The vortioxetine 10-mg group showed separation from placebo on the Hospital Anxiety and Depression anxiety subscore (nominal p = 0.036). Duloxetine 60 mg significantly improved the primary end-point (p < 0.05 vs. placebo), validating the study. Nausea, dry mouth, diarrhoea, nasopharyngitis, headache, dizziness, somnolence, vomiting, dyspepsia, constipation and fatigue were reported in ≥ 5% of patients receiving vortioxetine. Rates of treatment-emergent sexual dysfunction (TESD) in the vortioxetine dosing groups were similar to placebo. CONCLUSION In this study, vortioxetine 2.5-, 5- and 10-mg once-daily doses showed no significant improvement in HAM-A total scores vs. placebo. Vortioxetine was well tolerated at all doses and was not associated with TESD.
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Shrestha SS, Pine DS, Luckenbaugh DA, Varnäs K, Henter ID, Innis RB, Mathé AA, Svenningsson P. Antidepressant effects on serotonin 1A/1B receptors in the rat brain using a gene x environment model. Neurosci Lett 2013; 559:163-8. [PMID: 24287374 DOI: 10.1016/j.neulet.2013.11.034] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 11/04/2013] [Accepted: 11/19/2013] [Indexed: 01/13/2023]
Abstract
A gene-environment (GxE) interaction is implicated in both the pathophysiology and treatment of major depressive disorder (MDD). This study modeled the effects of genetic vulnerability by using the Flinders sensitive line (FSL), a rat model of depression and its control counterpart-the Flinders resistant line (FRL). The effects of environmental vulnerability (e.g., early-life stress) were modeled by using maternal separation. Rats (n=105) were drawn from four groups reflecting experimental crossing of strain (FSL vs. FRL) and early-life stress (high vs. low) to assess the effects of two antidepressants (escitalopram or nortriptyline) compared to vehicle. Quantitative in vitro autoradiography was performed using [(125)I]MPPI (5-HT1A) and [(125)I]CYP (5-HT1B) in prefrontal cortex (PFC) and hippocampus. Stringent, Bonferroni-corrected statistical analyses showed significant strain-by-rearing-by-treatment (three-way) interactions in PFC 5-HT1A and hippocampal 5-HT1B receptors. Either vulnerability reduced serotonergic binding; no additive effects were associated with the two vulnerabilities. Both antidepressants increased hippocampal 5-HT1B receptor binding; however, only nortriptyline selectively increased PFC 5-HT1A receptor binding. Taken together, our findings demonstrate that antidepressant effects on the serotonergic system are shaped by a GxE interaction that depends on antidepressant class and brain region.
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Affiliation(s)
- Stal Saurav Shrestha
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden; Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA.
| | - Daniel S Pine
- Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA
| | - David A Luckenbaugh
- Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA
| | - Katarina Varnäs
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Ioline D Henter
- Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA
| | - Robert B Innis
- Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, USA
| | - Aleksander A Mathé
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Per Svenningsson
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
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El-Hage W, Leman S, Camus V, Belzung C. Mechanisms of antidepressant resistance. Front Pharmacol 2013; 4:146. [PMID: 24319431 PMCID: PMC3837246 DOI: 10.3389/fphar.2013.00146] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 11/05/2013] [Indexed: 12/28/2022] Open
Abstract
Depression is one of the most frequent and severe mental disorder. Since the discovery of antidepressant (AD) properties of the imipramine and then after of other tricyclic compounds, several classes of psychotropic drugs have shown be effective in treating major depressive disorder (MDD). However, there is a wide range of variability in response to ADs that might lead to non response or partial response or in increased rate of relapse or recurrence. The mechanisms of response to AD therapy are poorly understood, and few biomarkers are available than can predict response to pharmacotherapy. Here, we will first review markers that can be used to predict response to pharmacotherapy, such as markers of drug metabolism or blood-brain barrier (BBB) function, the activity of specific brain areas or neurotransmitter systems, hormonal dysregulations or plasticity, and related molecular targets. We will describe both clinical and preclinical studies and describe factors that might affect the expression of these markers, including environmental or genetic factors and comorbidities. This information will permit us to suggest practical recommendations and innovative treatment strategies to improve therapeutic outcomes.
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Affiliation(s)
- Wissam El-Hage
- INSERM 930, Faculté de Sciences et Techniques, Université François Rabelais Tours, France ; Centre Hospitalier Régional Universitaire de Tours, Centre Expert Dépression Résistante, Fondation FondaMental Tours, France
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Griebel G, Holmes A. 50 years of hurdles and hope in anxiolytic drug discovery. Nat Rev Drug Discov 2013; 12:667-87. [PMID: 23989795 DOI: 10.1038/nrd4075] [Citation(s) in RCA: 288] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Anxiety disorders are the most prevalent group of psychiatric diseases, and have high personal and societal costs. The search for novel pharmacological treatments for these conditions is driven by the growing medical need to improve on the effectiveness and the side effect profile of existing drugs. A huge volume of data has been generated by anxiolytic drug discovery studies, which has led to the progression of numerous new molecules into clinical trials. However, the clinical outcome of these efforts has been disappointing, as promising results with novel agents in rodent studies have very rarely translated into effectiveness in humans. Here, we analyse the major trends from preclinical studies over the past 50 years conducted in the search for new drugs beyond those that target the prototypical anxiety-associated GABA (γ-aminobutyric acid)-benzodiazepine system, which have focused most intensively on the serotonin, neuropeptide, glutamate and endocannabinoid systems. We highlight various key issues that may have hampered progress in the field, and offer recommendations for how anxiolytic drug discovery can be more effective in the future.
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Affiliation(s)
- Guy Griebel
- Sanofi, Exploratory Unit, Chilly-Mazarin 91385, France
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Neurogenesis along the septo-temporal axis of the hippocampus: Are depression and the action of antidepressants region-specific? Neuroscience 2013; 252:234-52. [DOI: 10.1016/j.neuroscience.2013.08.017] [Citation(s) in RCA: 166] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 07/01/2013] [Accepted: 08/12/2013] [Indexed: 01/25/2023]
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Gardier AM. Antidepressant activity: contribution of brain microdialysis in knock-out mice to the understanding of BDNF/5-HT transporter/5-HT autoreceptor interactions. Front Pharmacol 2013; 4:98. [PMID: 23964240 PMCID: PMC3737470 DOI: 10.3389/fphar.2013.00098] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 07/17/2013] [Indexed: 12/31/2022] Open
Abstract
Why antidepressants vary in terms of efficacy is currently unclear. Despite the leadership of selective serotonin reuptake inhibitors (SSRIs) in the treatment of depression, the precise neurobiological mechanisms involved in their therapeutic action are poorly understood. A better knowledge of molecular interactions between monoaminergic system, pre- and post-synaptic partners, brain neuronal circuits and regions involved may help to overcome limitations of current treatments and identify new therapeutic targets. Intracerebral in vivo microdialysis (ICM) already provided important information about the brain mechanism of action of antidepressants first in anesthetized rats in the early 1990s, and since then in conscious wild-type or knock-out mice. The principle of ICM is based on the balance between release of neurotransmitters (e.g., monoamines) and reuptake by selective transporters [e.g., serotonin transporter for serotonin 5-hydroxytryptamine (5-HT)]. Complementary to electrophysiology, this technique reflects pre-synaptic monoamines release and intrasynaptic events corresponding to ≈80% of whole brain tissue content. The inhibitory role of serotonergic autoreceptors infers that they limit somatodendritic and nerve terminal 5-HT release. It has been proposed that activation of 5-HT1A and 5-HT1B receptor sub-types limits the antidepressant-like activity of SSRIs. This hypothesis is based partially on results obtained in ICM experiments performed in naïve, non-stressed rodents. The present review will first remind the principle and methodology of ICM performed in mice. The crucial need of developing animal models that display anxiety and depression-like behaviors, neurochemical and brain morphological phenotypes reminiscent of these mood disorders in humans, will be underlined. Recently developed genetic mouse models have been generated to independently manipulate 5-HT1A auto and heteroreceptors and ICM helped to clarify the role of the pre-synaptic component, i.e., by measuring extracellular levels of neurotransmitters in serotonergic nerve terminal regions and raphe nuclei. Finally, we will summarize main advantages of using ICM in mice through recent examples obtained in knock-outs (drug infusion through the ICM probe allows the search of a correlation between changes in extracellular neurotransmitter levels and antidepressant-like activity) or alternatives (infusion of a small-interfering RNA suppressing receptor functions in the mouse brain). We will also focus this review on post-synaptic components such as brain-derived neurotrophic factor in adult hippocampus that plays a crucial role in the neurogenic and anxiolytic/antidepressant-like activity of chronic SSRI treatment. Limitations of ICM will also be considered.
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Affiliation(s)
- Alain M Gardier
- EA 3544 "Pharmacologie des troubles anxio-dépressifs et Neurogenèse", Faculté de Pharmacie, Université Paris-Sud Chatenay-Malabry, France
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Antidepressant and anxiolytic potential of the multimodal antidepressant vortioxetine (Lu AA21004) assessed by behavioural and neurogenesis outcomes in mice. Neuropharmacology 2013; 73:147-59. [PMID: 23721744 DOI: 10.1016/j.neuropharm.2013.05.014] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Revised: 05/06/2013] [Accepted: 05/07/2013] [Indexed: 12/28/2022]
Abstract
Vortioxetine (Lu AA21004) is an investigational novel antidepressant with multimodal activity that functions as a 5-HT3, 5-HT7 and 5-HT(1D) receptor antagonist, 5-HT(1B) receptor partial agonist, 5-HT(1A) receptor agonist and inhibitor of the 5-HT transporter in vitro. Here we explore its anxiolytic and antidepressant potential in adult mice. Vortioxetine was assessed in BalB/cJ@RJ mice using the open-field and forced-swim tests (acute: p.o. 1 h, repeated: daily p.o. 21 days), and in 129S6/SvEvTac mice using the novelty suppressed feeding paradigm (acute: p.o. 1 h, sustained: daily p.o. 14 or 21 days). Fluoxetine and diazepam were controls. Acute and repeated dosing of vortioxetine produced more pronounced anxiolytic- and antidepressant-like activities than fluoxetine. Vortioxetine significantly increased cell proliferation and cell survival and stimulated maturation of immature granule cells in the subgranular zone of the dentate gyrus of the hippocampus after 21 days of treatment. After 14 days, a high dose of vortioxetine increased dendritic length and the number of dendrite intersections, suggesting that vortioxetine accelerates the maturation of immature neurons. Vortioxetine displays an antidepressant and anxiolytic profile following repeated administration associated with increased neurogenesis at several stages. Vortioxetine effects were observed at low levels of 5-HT transporter occupancy, suggesting an alternative mechanism of action to 5-HT reuptake inhibition.
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Tanti A, Belzung C. Hippocampal neurogenesis: a biomarker for depression or antidepressant effects? Methodological considerations and perspectives for future research. Cell Tissue Res 2013; 354:203-19. [PMID: 23595256 DOI: 10.1007/s00441-013-1612-z] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 03/08/2013] [Indexed: 12/22/2022]
Abstract
Whereas animal models of depression are associated with decreased adult hippocampal neurogenesis, antidepressant treatments, including pharmacotherapy but also electroconvulsive therapy, have the opposite action, as they stimulate cell proliferation and the survival and maturation of newborn dentate gyrus neurons. Although the lack of these new cells is not causally involved in depression, as their absence does not trigger a depressive-episode per se, their loss has been shown to be causally involved in the ability of chronic monoaminergic antidepressants to achieve remission. However, the process by which the stimulation of hippocampal neurogenesis can elicit recovery after a depressive-like episode is poorly understood. The accepted view is that hippocampal newborn neurons integrate into the hippocampal network and thus participate in hippocampal cognitive functions crucial for remission. The hippocampus is associated with a wide range of such functions, including spatial navigation, pattern separation, encoding of new contextual information, emotional behavior and control over the hypothalamic-pituitary-adrenal axis. The present review aims at discussing each of these functions and tries to identify the process by which newborn cells participate in remission after successful therapy. Finally, future directions are proposed for a better understanding of these mechanisms.
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Affiliation(s)
- Arnaud Tanti
- UFR Sciences et Techniques, Université François Rabelais & INSERM 930, Parc Grandmont, 37200, Tours, France,
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Bahi A, Dreyer JL. Hippocampus-specific deletion of tissue plasminogen activator "tPA" in adult mice impairs depression- and anxiety-like behaviors. Eur Neuropsychopharmacol 2012; 22:672-82. [PMID: 22377193 DOI: 10.1016/j.euroneuro.2012.01.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Revised: 12/12/2011] [Accepted: 01/12/2012] [Indexed: 10/28/2022]
Abstract
Anxiety and depression are multifactorial disorders that have become prominent health problems all over the world. Neurotrophic factors have emerged underlying pathogenesis of these diseases. Although a number of studies indicate that the hippocampus-brain-derived neurotrophic factor (BDNF) may be involved in these psychiatric illnesses, little is known about the molecular mediators of these disorders. In this study we further investigate the role of tissue plasminogen activator (tPA), a serine protease involved in pro-BDNF cleavage to BDNF, in depression and anxiety-like behaviors in adult mice. To address this issue, we investigated the effect of hippocampus tPA manipulation, using viral vectors, on anxiety- and depression-like behaviors, including the marble burying test (MBT), elevated plus maze (EPM), tail suspension test (TST), novelty suppressed feeding (NSF) and forced swim test (FST). Our results showed that tPA knock-down - using lentiviral vectors expressing specific short hairpin RNAs (LV-shRNA) - increased the number of buried marbles together with the digging time in the MBT and decreased the time spent in open the arms of an EPM. In addition, tPA-knock down in the hippocampus increased immobility in the FST and TST, and increased time to feed in the NSF test. These effects were reversed when tPA-over-expressing vectors (LV-tPA) were injected in the hippocampus. We also found that BDNF protein levels were elevated in the hippocampus of mice receiving tPA-expressing vectors. Together, our results imply that tPA manipulation may provide an effective therapeutic intervention for depression and anxiety disorders.
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Affiliation(s)
- Amine Bahi
- Department of Anatomy, Tawam Medical Campus, United Arab Emirates University, Al Ain, United Arab Emirates.
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Ventral hippocampal molecular pathways and impaired neurogenesis associated with 5-HT1A and 5-HT1B receptors disruption in mice. Neurosci Lett 2012; 521:20-5. [DOI: 10.1016/j.neulet.2012.05.046] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Revised: 05/10/2012] [Accepted: 05/12/2012] [Indexed: 02/06/2023]
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Adhikari A, Topiwala MA, Gordon JA. Single units in the medial prefrontal cortex with anxiety-related firing patterns are preferentially influenced by ventral hippocampal activity. Neuron 2011; 71:898-910. [PMID: 21903082 DOI: 10.1016/j.neuron.2011.07.027] [Citation(s) in RCA: 193] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/27/2011] [Indexed: 10/17/2022]
Abstract
The medial prefrontal cortex (mPFC) and ventral hippocampus (vHPC) functionally interact during innate anxiety tasks. To explore the consequences of this interaction, we examined task-related firing of single units from the mPFC of mice exploring standard and modified versions of the elevated plus maze (EPM), an innate anxiety paradigm. Hippocampal local field potentials (LFPs) were simultaneously monitored. The population of mPFC units distinguished between safe and aversive locations within the maze, regardless of the nature of the anxiogenic stimulus. Strikingly, mPFC units with stronger task-related activity were more strongly coupled to theta-frequency activity in the vHPC LFP. Lastly, task-related activity was inversely correlated with behavioral measures of anxiety. These results clarify the role of the vHPC-mPFC circuit in innate anxiety and underscore how specific inputs may be involved in the generation of behaviorally relevant neural activity within the mPFC.
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Affiliation(s)
- Avishek Adhikari
- Department of Biological Sciences, Columbia University, New York, NY 10032, USA
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Sartori SB, Whittle N, Hetzenauer A, Singewald N. Magnesium deficiency induces anxiety and HPA axis dysregulation: modulation by therapeutic drug treatment. Neuropharmacology 2011; 62:304-12. [PMID: 21835188 PMCID: PMC3198864 DOI: 10.1016/j.neuropharm.2011.07.027] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 07/16/2011] [Accepted: 07/18/2011] [Indexed: 01/12/2023]
Abstract
Preclinical and some clinical studies suggest a relationship between perturbation in magnesium (Mg2+) homeostasis and pathological anxiety, although the underlying mechanisms remain largely unknown. Since there is evidence that Mg2+ modulates the hypothalamic-pituitary adrenal (HPA) axis, we tested whether enhanced anxiety-like behaviour can be reliably elicited by dietary Mg2+ deficiency and whether Mg2+ deficiency is associated with altered HPA axis function. Compared with controls, Mg2+ deficient mice did indeed display enhanced anxiety-related behaviour in a battery of established anxiety tests. The enhanced anxiety-related behaviour of Mg2+ deficient mice was sensitive to chronic desipramine treatment in the hyponeophagia test and to acute diazepam treatment in the open arm exposure test. Mg2+ deficiency caused an increase in the transcription of the corticotropin releasing hormone in the paraventricular hypothalamic nucleus (PVN), and elevated ACTH plasma levels, pointing to an enhanced set-point of the HPA axis. Chronic treatment with desipramine reversed the identified abnormalities of the stress axis. Functional mapping of neuronal activity using c-Fos revealed hyper-excitability in the PVN of anxious Mg2+ deficient mice and its normalisation through diazepam treatment. Overall, the present findings demonstrate the robustness and validity of the Mg2+ deficiency model as a mouse model of enhanced anxiety, showing sensitivity to treatment with anxiolytics and antidepressants. It is further suggested that dysregulations in the HPA axis may contribute to the hyper-emotionality in response to dietary induced hypomagnesaemia. This article is part of a Special Issue entitled ‘Anxiety and Depression’.
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Affiliation(s)
- S B Sartori
- Department of Pharmacology and Toxicology, Institute of Pharmacy, and Centre for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Peter-Mayr-Strasse 1, A-6020 Innsbruck, Austria.
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Serotonin-1A autoreceptors are necessary and sufficient for the normal formation of circuits underlying innate anxiety. J Neurosci 2011; 31:6008-18. [PMID: 21508226 DOI: 10.1523/jneurosci.5836-10.2011] [Citation(s) in RCA: 146] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Identifying the factors contributing to the etiology of anxiety and depression is critical for the development of more efficacious therapies. Serotonin (5-HT) is intimately linked to both disorders. The inhibitory serotonin-1A (5-HT(1A)) receptor exists in two separate populations with distinct effects on serotonergic signaling: (1) an autoreceptor that limits 5-HT release throughout the brain and (2) a heteroreceptor that mediates inhibitory responses to released 5-HT. Traditional pharmacologic and transgenic strategies have not addressed the distinct roles of these two receptor populations. Here we use a recently developed genetic mouse system to independently manipulate 5-HT(1A) autoreceptor and heteroreceptor populations. We show that 5-HT(1A) autoreceptors act to affect anxiety-like behavior. In contrast, 5-HT(1A) heteroreceptors affect responses to forced swim stress, without effects on anxiety-like behavior. Together with our previously reported work, these results establish distinct roles for the two receptor populations, providing evidence that signaling through endogenous 5-HT(1A) autoreceptors is necessary and sufficient for the establishment of normal anxiety-like behavior.
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