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Panwar A, Rentsendorj A, Jhun M, Cohen RM, Cordner R, Gull N, Pechnick RN, Duvall G, Mardiros A, Golchian D, Schubloom H, Jin LW, Van Dam D, Vermeiren Y, De Reu H, De Deyn PP, Raskatov JA, Black KL, Irvin DK, Williams BA, Wheeler CJ. Antigen-specific age-related memory CD8 T cells induce and track Alzheimer's-like neurodegeneration. Proc Natl Acad Sci U S A 2024; 121:e2401420121. [PMID: 38995966 PMCID: PMC11260139 DOI: 10.1073/pnas.2401420121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 05/23/2024] [Indexed: 07/14/2024] Open
Abstract
Cerebral (Aβ) plaque and (pTau) tangle deposition are hallmarks of Alzheimer's disease (AD), yet are insufficient to confer complete AD-like neurodegeneration experimentally. Factors acting upstream of Aβ/pTau in AD remain unknown, but their identification could enable earlier diagnosis and more effective treatments. T cell abnormalities are emerging AD hallmarks, and CD8 T cells were recently found to mediate neurodegeneration downstream of tangle deposition in hereditary neurodegeneration models. The precise impact of T cells downstream of Aβ/pTau, however, appears to vary depending on the animal model. Our prior work suggested that antigen-specific memory CD8 T ("hiT") cells act upstream of Aβ/pTau after brain injury. Here, we examine whether hiT cells influence sporadic AD-like pathophysiology upstream of Aβ/pTau. Examining neuropathology, gene expression, and behavior in our hiT mouse model we show that CD8 T cells induce plaque and tangle-like deposition, modulate AD-related genes, and ultimately result in progressive neurodegeneration with both gross and fine features of sporadic human AD. T cells required Perforin to initiate this pathophysiology, and IFNγ for most gene expression changes and progression to more widespread neurodegenerative disease. Analogous antigen-specific memory CD8 T cells were significantly elevated in the brains of human AD patients, and their loss from blood corresponded to sporadic AD and related cognitive decline better than plasma pTau-217, a promising AD biomarker candidate. We identify an age-related factor acting upstream of Aβ/pTau to initiate AD-like pathophysiology, the mechanisms promoting its pathogenicity, and its relevance to human sporadic AD.
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Affiliation(s)
- Akanksha Panwar
- Department Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, Los Angeles, CA90048
| | - Altan Rentsendorj
- Department Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, Los Angeles, CA90048
| | - Michelle Jhun
- Department Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, Los Angeles, CA90048
| | - Robert M. Cohen
- Department Psychiatry & Behavioral Sciences and Neuroscience Program, Graduate Division of Biological and Biomedical Sciences (GDBBS), Emory University, Atlanta, GA30322
| | - Ryan Cordner
- Department Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, Los Angeles, CA90048
- Department Biomedical & Translational Sciences, Cedars-Sinai Medical Center, Los Angeles, CA90048
| | - Nicole Gull
- Department Biomedical & Translational Sciences, Cedars-Sinai Medical Center, Los Angeles, CA90048
| | - Robert N. Pechnick
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific Western University of Health Sciences, Pomona, CA91766
| | - Gretchen Duvall
- Department Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, Los Angeles, CA90048
| | - Armen Mardiros
- Department Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, Los Angeles, CA90048
| | - David Golchian
- Department Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, Los Angeles, CA90048
| | - Hannah Schubloom
- Department Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, Los Angeles, CA90048
| | - Lee-Way Jin
- Department Medical Pathology and Laboratory Medicine, Laboratory Medicine, Medical Investigation of Neurodevelopmental Disorders (M.I.N.D.) Institute, University of California, Davis, Sacramento, CA95817
| | - Debby Van Dam
- Department of Biomedical Sciences, Institute Born-Bunge, Laboratory of Neurochemistry and Behavior, University of Antwerp, Antwerp2610, Belgium
- Department of Neurology and Alzheimer Research Center, University of Groningen and University Medical Center Groningen, Groningen AB9700, Netherlands
| | - Yannick Vermeiren
- Department of Biomedical Sciences, Institute Born-Bunge, Laboratory of Neurochemistry and Behavior, University of Antwerp, Antwerp2610, Belgium
- Faculty of Medicine & Health Sciences, Department of Translational Neurosciences, University of Antwerp, Antwerp2610, Belgium
- Division of Human Nutrition and Health, Chair Group of Nutritional Biology, Wageningen University & Research, Wageningen AA6700, The Netherlands
| | - Hans De Reu
- Faculty of Medicine and Health Sciences, Vaccine and Infectious Disease Institute, Laboratory of Experimental Hematology, University of Antwerp, Antwerp2610, Belgium
| | - Peter Paul De Deyn
- Department of Biomedical Sciences, Institute Born-Bunge, Laboratory of Neurochemistry and Behavior, University of Antwerp, Antwerp2610, Belgium
- Department of Neurology and Alzheimer Research Center, University of Groningen and University Medical Center Groningen, Groningen AB9700, Netherlands
- Department of Neurology, Memory Clinic of Hospital Network Antwerp, Middelheim and Hoge Beuken, Antwerp BE-2660, Belgium
- Department of Chemistry & Biochemistry, University of California, Santa Cruz, CA95064
| | - Jevgenij A. Raskatov
- Department of Chemistry & Biochemistry, University of California, Santa Cruz, CA95064
| | - Keith L. Black
- Department Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, Los Angeles, CA90048
| | - Dwain K. Irvin
- Department Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, Los Angeles, CA90048
- NovAccess Global and StemVax LLC, Cleveland, OH44023
| | - Brian A. Williams
- Transcriptome Function and Technology Program, Department of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA91125
| | - Christopher J. Wheeler
- Department Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, Los Angeles, CA90048
- Department of Chemistry & Biochemistry, University of California, Santa Cruz, CA95064
- NovAccess Global and StemVax LLC, Cleveland, OH44023
- Society for Brain Mapping & Therapeutics, World Brain Mapping Foundation, Pacific Palisades, CA90272
- T-Neuro Pharma, Inc., Albuquerque, NM87123
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Rahmi U, Goenawan H, Sylviana N, Setiawan I, Putri ST, Andriyani S, Fitriana LA. Exercise induction at expression immediate early gene (c-Fos, ARC, EGR-1) in the hippocampus: a systematic review. Dement Neuropsychol 2024; 18:e20230015. [PMID: 38628561 PMCID: PMC11019719 DOI: 10.1590/1980-5764-dn-2023-0015] [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: 03/16/2023] [Revised: 11/06/2023] [Accepted: 11/17/2023] [Indexed: 04/19/2024] Open
Abstract
The immediate early gene exhibits activation markers in the nervous system consisting of ARC, EGR-1, and c-Fos and is related to synaptic plasticity, especially in the hippocampus. Immediate early gene expression is affected by physical exercise, which induces direct ARC, EGR-1, and c-Fos expression. Objective To assess the impact of exercise, we conducted a literature study to determine the expression levels of immediate early genes (ARC, c-Fos, and EGR-1). Methods The databases accessed for online literature included PubMed-Medline, Scopus, and ScienceDirect. The original English articles were selected using the following keywords in the title: (Exercise OR physical activity) AND (c-Fos) AND (Hippocampus), (Exercise OR physical activity) AND (ARC) AND (Hippocampus), (Exercise OR physical activity) AND (EGR-1 OR zif268) AND (Hippocampus). Results Physical exercise can affect the expression of EGR-1, c-Fos, and ARC in the hippocampus, an important part of the brain involved in learning and memory. High-intensity physical exercise can increase c-Fos expression, indicating neural activation. Furthermore, the expression of the ARC gene also increases due to physical exercise. ARC is a gene that plays a role in synaptic plasticity and regulation of learning and memory, changes in synaptic structure and increased synaptic connections, while EGR-1 also plays a role in synaptic plasticity, a genetic change that affects learning and memory. Overall, exercise or regular physical exercise can increase the expression of ARC, c-Fos, and EGR-1 in the hippocampus. This reflects the changes in neuroplasticity and synaptic plasticity that occur in response to physical activity. These changes can improve cognitive function, learning, and memory. Conclusion c-Fos, EGR-1, and ARC expression increases in hippocampal neurons after exercise, enhancing synaptic plasticity and neurogenesis associated with learning and memory.
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Affiliation(s)
- Upik Rahmi
- Universitas Pendidikan Indonesia, Department of Nursing, Bandung, West Java, Indonesia
- Universitas Padjadjaran, Department of Medicine, Bandung, West Java, Indonesia
| | - Hanna Goenawan
- Universitas Padjadjaran, Department of Medicine, Bandung, West Java, Indonesia
| | - Nova Sylviana
- Universitas Padjadjaran, Department of Medicine, Bandung, West Java, Indonesia
| | - Iwan Setiawan
- Universitas Padjadjaran, Department of Medicine, Bandung, West Java, Indonesia
| | - Suci Tuty Putri
- Universitas Pendidikan Indonesia, Department of Nursing, Bandung, West Java, Indonesia
| | - Septian Andriyani
- Universitas Pendidikan Indonesia, Department of Nursing, Bandung, West Java, Indonesia
| | - Lisna Anisa Fitriana
- Universitas Pendidikan Indonesia, Department of Nursing, Bandung, West Java, Indonesia
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Panwar A, Rentsendorj A, Jhun M, Cohen RM, Cordner R, Gull N, Pechnick RN, Duvall G, Mardiros A, Golchian D, Schubloom H, Jin LW, Van Dam D, Vermeiren Y, De Reu H, De Deyn PP, Raskatov JA, Black KL, Irvin DK, Williams BA, Wheeler CJ. Antigen-specific age-related memory CD8 T cells induce and track Alzheimer's-like neurodegeneration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.22.576704. [PMID: 38328072 PMCID: PMC10849535 DOI: 10.1101/2024.01.22.576704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Cerebral (Aβ) plaque and (pTau) tangle deposition are hallmarks of Alzheimer's disease (AD), yet are insufficient to confer complete AD-like neurodegeneration experimentally. Factors acting upstream of Aβ/pTau in AD remain unknown, but their identification could enable earlier diagnosis and more effective treatments. T cell abnormalities are emerging AD hallmarks, and CD8 T cells were recently found to mediate neurodegeneration downstream of tangle deposition in hereditary neurodegeneration models. The precise impact of T cells downstream of Aβ/fibrillar pTau, however, appears to vary depending on the animal model used. Our prior work suggested that antigen-specific memory CD8 T (" hi T") cells act upstream of Aβ/pTau after brain injury. Here we examine whether hi T cells influence sporadic AD-like pathophysiology upstream of Aβ/pTau. Examining neuropathology, gene expression, and behavior in our hi T mouse model we show that CD8 T cells induce plaque and tangle-like deposition, modulate AD-related genes, and ultimately result in progressive neurodegeneration with both gross and fine features of sporadic human AD. T cells required Perforin to initiate this pathophysiology, and IFNγ for most gene expression changes and progression to more widespread neurodegenerative disease. Analogous antigen-specific memory CD8 T cells were significantly elevated in the brains of human AD patients, and their loss from blood corresponded to sporadic AD and related cognitive decline better than plasma pTau-217, a promising AD biomarker candidate. Our work is the first to identify an age-related factor acting upstream of Aβ/pTau to initiate AD-like pathophysiology, the mechanisms promoting its pathogenicity, and its relevance to human sporadic AD. Significance Statement This study changes our view of Alzheimer's Disease (AD) initiation and progression. Mutations promoting cerebral beta-amyloid (Aβ) deposition guarantee rare genetic forms of AD. Thus, the prevailing hypothesis has been that Aβ is central to initiation and progression of all AD, despite contrary animal and patient evidence. We show that age-related T cells generate neurodegeneration with compelling features of AD in mice, with distinct T cell functions required for pathological initiation and neurodegenerative progression. Knowledge from these mice was applied to successfully predict previously unknown features of human AD and generate novel tools for its clinical management.
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Ngoupaye GT, Mokgokong M, Madlala T, Mabandla MV. Alteration of the α5 GABA receptor and 5HTT lead to cognitive deficits associated with major depressive-like behaviors in a 14-day combined stress rat model. Int J Neurosci 2023; 133:959-976. [PMID: 34937496 DOI: 10.1080/00207454.2021.2019033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 07/13/2021] [Accepted: 12/08/2021] [Indexed: 10/19/2022]
Abstract
INTRODUCTION Current models used to study the pathophysiology of major depressive disorder (MDD) are laborious and time consuming. This study examined the effect of a 14-day combined stress model (CS; corticosterone injection and restraint stress) in male Sprague-Dawley rats and also compare the effect of CS versus 28-day corticosterone treatment on depressive-like behaviour and cognitive deficits. MATERIEL AND METHODS Depressive-like behaviours and cognitive deficits were assessed in the forced swim test (FST), sucrose preference (SPT), Morris water maze (MWM) and novel object recognition (NORT) tests. Real-time PCR and ELISA were respectively used to detect expression of the serotonin transporter (5-HTT), serotonin 1 A receptor (5-HT1A), α5 GABAA receptor, and the concentrations of corticosterone (plasma), GABA and acetylcholinesterase (AChE) in the hippocampus and Prefrontal cortex (PFC).Results CS group showed increased immobility time in the FST, time to reach the MWM platform, higher corticosterone level, and increased expressions of hippocampal and PFC 5-HT1A and α5 GABAA receptors, and AChE compared to their control groups. In contrast, reductions in SPT ratio, discrimination index in NORT, time in target quadrant, and hippocampal 5-HTT expression was noted relative to their control group. Compared to the 28-day corticosterone only group, PFC 5-HT1A, Hippocampal 5-HTT were reduced, while PFC 5-HTT, Hippocampal α5 GABAA receptors, and AChE concentrations were higher in the CS group. CONCLUSION Our CS model induced depressive-like behaviour with early cognitive deficits in rats affecting both hippocampus and PFC. The CS model may be useful in investigating new and comprehensive treatment strategies for MDD.
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Affiliation(s)
- Gwladys Temkou Ngoupaye
- Discipline of Human Physiology, School of Laboratory Medicine & Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
- Department of Animal Biology, Faculty of Science, University of Dschang, Dschang, Cameroon
| | - Makwena Mokgokong
- Discipline of Human Physiology, School of Laboratory Medicine & Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Thobeka Madlala
- Discipline of Human Physiology, School of Laboratory Medicine & Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Musa Vuyisile Mabandla
- Discipline of Human Physiology, School of Laboratory Medicine & Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
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5
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Dyomina AV, Smolensky IV, Zaitsev AV. Refinement of the Barnes and Morris water maze protocols improves characterization of spatial cognitive deficits in the lithium-pilocarpine rat model of epilepsy. Epilepsy Behav 2023; 147:109391. [PMID: 37619464 DOI: 10.1016/j.yebeh.2023.109391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 07/28/2023] [Accepted: 07/30/2023] [Indexed: 08/26/2023]
Abstract
Temporal lobe epilepsy (TLE) often causes cognitive impairment, especially a decline in spatial memory. Reductions in spatial memory and learning are also common in rodent models of TLE. The Morris water maze and the Barnes maze are the standard methods for evaluating spatial learning and memory in rodents. However, animals with TLE may exhibit agitation, distress, and fail to follow the paradigmatic context of these tests, making the interpretation of experimental data difficult. This study optimized the procedure of the Morris water maze and the Barnes maze to evaluate spatial learning and memory in rats with the lithium-pilocarpine TLE model (LPM rats). It was demonstrated that LPM rats required a mandatory and prolonged habituation stage for both tests. Therefore, the experimental rats performed relatively well on these tests. Nevertheless, LPM rats exhibited a slower learning process compared to the control rats. LPM rats also showed a reduction in spatial memory formation. This was more pronounced in the Barnes maze. Also, LPM rats utilized a sequential strategy for searching in the Barnes maze and were incapable of developing a more efficient spatial search strategy that is common in control animals. The Barnes maze may be a better choice for assessing search strategies, learning deficits, and spatial memory in rats with TLE when choosing between the two tests. This is because of the risk of unexpected seizure occurrence during the Morris water maze tests, and the potential risks for animal welfare.
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Affiliation(s)
- Alexandra V Dyomina
- Sechenov Institute of Evolutionary Physiology and Biochemistry of RAS (IEPhB), 44, Toreza pr., Saint Petersburg 194223, Russia
| | - Ilya V Smolensky
- Sechenov Institute of Evolutionary Physiology and Biochemistry of RAS (IEPhB), 44, Toreza pr., Saint Petersburg 194223, Russia; Department of Community Health, University of Fribourg, Chemin du Musée 4, 1700 Fribourg, Switzerland; Department of Biomedicine, University of Basel, Hebelstrasse 20, 4056 Basel, Switzerland
| | - Aleksey V Zaitsev
- Sechenov Institute of Evolutionary Physiology and Biochemistry of RAS (IEPhB), 44, Toreza pr., Saint Petersburg 194223, Russia.
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Lang B, Kahnau P, Hohlbaum K, Mieske P, Andresen NP, Boon MN, Thöne-Reineke C, Lewejohann L, Diederich K. Challenges and advanced concepts for the assessment of learning and memory function in mice. Front Behav Neurosci 2023; 17:1230082. [PMID: 37809039 PMCID: PMC10551171 DOI: 10.3389/fnbeh.2023.1230082] [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: 05/28/2023] [Accepted: 09/05/2023] [Indexed: 10/10/2023] Open
Abstract
The mechanisms underlying the formation and retrieval of memories are still an active area of research and discussion. Manifold models have been proposed and refined over the years, with most assuming a dichotomy between memory processes involving non-conscious and conscious mechanisms. Despite our incomplete understanding of the underlying mechanisms, tests of memory and learning count among the most performed behavioral experiments. Here, we will discuss available protocols for testing learning and memory using the example of the most prevalent animal species in research, the laboratory mouse. A wide range of protocols has been developed in mice to test, e.g., object recognition, spatial learning, procedural memory, sequential problem solving, operant- and fear conditioning, and social recognition. Those assays are carried out with individual subjects in apparatuses such as arenas and mazes, which allow for a high degree of standardization across laboratories and straightforward data interpretation but are not without caveats and limitations. In animal research, there is growing concern about the translatability of study results and animal welfare, leading to novel approaches beyond established protocols. Here, we present some of the more recent developments and more advanced concepts in learning and memory testing, such as multi-step sequential lockboxes, assays involving groups of animals, as well as home cage-based assays supported by automated tracking solutions; and weight their potential and limitations against those of established paradigms. Shifting the focus of learning tests from the classical experimental chamber to settings which are more natural for rodents comes with a new set of challenges for behavioral researchers, but also offers the opportunity to understand memory formation and retrieval in a more conclusive way than has been attainable with conventional test protocols. We predict and embrace an increase in studies relying on methods involving a higher degree of automatization, more naturalistic- and home cage-based experimental setting as well as more integrated learning tasks in the future. We are confident these trends are suited to alleviate the burden on animal subjects and improve study designs in memory research.
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Affiliation(s)
- Benjamin Lang
- Animal Behavior and Laboratory Animal Science, Department of Veterinary Medicine, Institute for Animal Welfare, Free University of Berlin, Berlin, Germany
- Science of Intelligence, Research Cluster of Excellence, Berlin, Germany
| | - Pia Kahnau
- Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Katharina Hohlbaum
- Science of Intelligence, Research Cluster of Excellence, Berlin, Germany
- Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Paul Mieske
- Animal Behavior and Laboratory Animal Science, Department of Veterinary Medicine, Institute for Animal Welfare, Free University of Berlin, Berlin, Germany
- Science of Intelligence, Research Cluster of Excellence, Berlin, Germany
- Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Niek P. Andresen
- Science of Intelligence, Research Cluster of Excellence, Berlin, Germany
- Computer Vision and Remote Sensing, Technical University Berlin, Berlin, Germany
| | - Marcus N. Boon
- Science of Intelligence, Research Cluster of Excellence, Berlin, Germany
- Modeling of Cognitive Processes, Technical University of Berlin, Berlin, Germany
| | - Christa Thöne-Reineke
- Animal Behavior and Laboratory Animal Science, Department of Veterinary Medicine, Institute for Animal Welfare, Free University of Berlin, Berlin, Germany
- Science of Intelligence, Research Cluster of Excellence, Berlin, Germany
| | - Lars Lewejohann
- Animal Behavior and Laboratory Animal Science, Department of Veterinary Medicine, Institute for Animal Welfare, Free University of Berlin, Berlin, Germany
- Science of Intelligence, Research Cluster of Excellence, Berlin, Germany
- Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Kai Diederich
- Federal Institute for Risk Assessment (BfR), Berlin, Germany
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Mieske P, Scheinpflug J, Yorgan TA, Brylka L, Palme R, Hobbiesiefken U, Preikschat J, Lewejohann L, Diederich K. Effects of more natural housing conditions on the muscular and skeletal characteristics of female C57BL/6J mice. Lab Anim Res 2023; 39:9. [PMID: 37189184 DOI: 10.1186/s42826-023-00160-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 04/17/2023] [Accepted: 04/30/2023] [Indexed: 05/17/2023] Open
Abstract
BACKGROUND Enrichment of home cages in laboratory experiments offers clear advantages, but has been criticized in some respects. First, there is a lack of definition, which makes methodological uniformity difficult. Second, there is concern that the enrichment of home cages may increase the variance of results in experiments. Here, the influence of more natural housing conditions on physiological parameters of female C57BL/6J mice was investigated from an animal welfare point of view. For this purpose, the animals were kept in three different housing conditions: conventional cage housing, enriched housing and the semi naturalistic environment. The focus was on musculoskeletal changes after long-term environmental enrichment. RESULTS The housing conditions had a long-term effect on the body weight of the test animals. The more complex and natural the home cage, the heavier the animals. This was associated with increased adipose deposits in the animals. There were no significant changes in muscle and bone characteristics except for single clues (femur diameter, bone resorption marker CTX-1). Additionally, the animals in the semi naturalistic environment (SNE) were found to have the fewest bone anomalies. Housing in the SNE appears to have the least effect on stress hormone concentrations. The lowest oxygen uptake was observed in enriched cage housing. CONCLUSIONS Despite increasing values, observed body weights were in the normal and strain-typical range. Overall, musculoskeletal parameters were slightly improved and age-related effects appear to have been attenuated. The variances in the results were not increased by more natural housing. This confirms the suitability of the applied housing conditions to ensure and increase animal welfare in laboratory experiments.
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Affiliation(s)
- Paul Mieske
- German Center for the Protection of Laboratory Animals (Bf3R), Federal German Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany.
| | - Julia Scheinpflug
- German Center for the Protection of Laboratory Animals (Bf3R), Federal German Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Timur Alexander Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Laura Brylka
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Rupert Palme
- Unit of Physiology, Pathophysiology, and Experimental Endocrinology, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Ute Hobbiesiefken
- German Center for the Protection of Laboratory Animals (Bf3R), Federal German Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Juliane Preikschat
- German Center for the Protection of Laboratory Animals (Bf3R), Federal German Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Lars Lewejohann
- German Center for the Protection of Laboratory Animals (Bf3R), Federal German Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
- Animal Behavior and Laboratory Animal Science, Institute of Animal Welfare, Freie Universität Berlin, Königsweg 67, 14163, Berlin, Germany
| | - Kai Diederich
- German Center for the Protection of Laboratory Animals (Bf3R), Federal German Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
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8
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Shoji H, Ikeda K, Miyakawa T. Behavioral phenotype, intestinal microbiome, and brain neuronal activity of male serotonin transporter knockout mice. Mol Brain 2023; 16:32. [PMID: 36991468 PMCID: PMC10061809 DOI: 10.1186/s13041-023-01020-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 03/16/2023] [Indexed: 03/31/2023] Open
Abstract
The serotonin transporter (5-HTT) plays a critical role in the regulation of serotonin neurotransmission. Mice genetically deficient in 5-HTT expression have been used to study the physiological functions of 5-HTT in the brain and have been proposed as a potential animal model for neuropsychiatric and neurodevelopmental disorders. Recent studies have provided evidence for a link between the gut-brain axis and mood disorders. However, the effects of 5-HTT deficiency on gut microbiota, brain function, and behavior remain to be fully characterized. Here we investigated the effects of 5-HTT deficiency on different types of behavior, the gut microbiome, and brain c-Fos expression as a marker of neuronal activation in response to the forced swim test for assessing depression-related behavior in male 5-HTT knockout mice. Behavioral analysis using a battery of 16 different tests showed that 5-HTT-/- mice exhibited markedly reduced locomotor activity, decreased pain sensitivity, reduced motor function, increased anxiety-like and depression-related behavior, altered social behavior in novel and familiar environments, normal working memory, enhanced spatial reference memory, and impaired fear memory compared to 5-HTT+/+ mice. 5-HTT+/- mice showed slightly reduced locomotor activity and impaired social behavior compared to 5-HTT+/+ mice. Analysis of 16S rRNA gene amplicons showed that 5-HTT-/- mice had altered gut microbiota abundances, such as a decrease in Allobaculum, Bifidobacterium, Clostridium sensu stricto, and Turicibacter, compared to 5-HTT+/+ mice. This study also showed that after exposure to the forced swim test, the number of c-Fos-positive cells was higher in the paraventricular thalamus and lateral hypothalamus and was lower in the prefrontal cortical regions, nucleus accumbens shell, dorsolateral septal nucleus, hippocampal regions, and ventromedial hypothalamus in 5-HTT-/- mice than in 5-HTT+/+ mice. These phenotypes of 5-HTT-/- mice partially recapitulate clinical observations in humans with major depressive disorder. The present findings indicate that 5-HTT-deficient mice serve as a good and valid animal model to study anxiety and depression with altered gut microbial composition and abnormal neuronal activity in the brain, highlighting the importance of 5-HTT in brain function and the mechanisms underlying the regulation of anxiety and depression.
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Affiliation(s)
- Hirotaka Shoji
- Division of Systems Medical Science, Center for Medical Science, Fujita Health University, Toyoake, Aichi, 470-1192, Japan
| | - Kazutaka Ikeda
- Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506, Japan
| | - Tsuyoshi Miyakawa
- Division of Systems Medical Science, Center for Medical Science, Fujita Health University, Toyoake, Aichi, 470-1192, Japan.
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9
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Dudde A, Phi Van L, Schrader L, Obert AJ, Krause ET. Brain gain—Is the cognitive performance of domestic hens affected by a functional polymorphism in the serotonin transporter gene? Front Psychol 2022; 13:901022. [PMID: 36186393 PMCID: PMC9521620 DOI: 10.3389/fpsyg.2022.901022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 08/11/2022] [Indexed: 11/24/2022] Open
Abstract
The serotonin transporter (5-HTT) plays an important role in regulating serotonergic transmission via removal of serotonin (5-HT) from synaptic clefts. Alterations in 5-HTT expression and subsequent 5-HT transmission have been found to be associated with changes in behaviour, such as fearfulness or activity, in humans and other vertebrates. In humans, alterations in 5-HTT expression have been suggested to be able to lead to better learning performance, with more fearful persons being better at learning. Similar effects of the variation in the 5-HTT on fearfulness have been found in chickens, and in this study, we investigated effects on learning. Therefore, we tested 52 adult laying hens, differing in their functional 5-HTT genotype (W/W, W/D and D/D) in an operant learning paradigm in three different phases (initial learning, reversal learning and extinction) and in a tonic immobility test for fearfulness. We found that the 5-HTT polymorphism affects the initial learning performance of laying hens, with homogeneous wild-type (W/W) hens being the slowest learners, and the most fearful birds. W/W hens, showed significantly more choices to solve the initial learning task (LME, p = 0.031) and had the highest latencies in a tonic immobility test (p = 0.039), indicating the highest fearfulness. Our results provide interesting first insights into the role of 5-HTT in chickens and its sensitive interaction with the environment. We further suggest that the 5-HTT gene can be an interesting target gene for future breeding strategies as well as for further experimental studies.
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Affiliation(s)
- Anissa Dudde
- Institute of Animal Welfare and Animal Husbandry, Friedrich-Loeffler-Institut, Celle, Germany
- *Correspondence: Anissa Dudde,
| | - Loc Phi Van
- Institute of Animal Welfare and Animal Husbandry, Friedrich-Loeffler-Institut, Celle, Germany
| | - Lars Schrader
- Institute of Animal Welfare and Animal Husbandry, Friedrich-Loeffler-Institut, Celle, Germany
| | - Arnd J. Obert
- Hannover Medical School, Institute for Diagnostic and Interventional Radiology, Hannover, Germany
| | - E. Tobias Krause
- Institute of Animal Welfare and Animal Husbandry, Friedrich-Loeffler-Institut, Celle, Germany
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10
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Uzungil V, Tran H, Aitken C, Wilson C, Opazo CM, Li S, Payet JM, Mawal CH, Bush AI, Hale MW, Hannan AJ, Renoir T. Novel Antidepressant-Like Properties of the Iron Chelator Deferiprone in a Mouse Model of Depression. Neurotherapeutics 2022; 19:1662-1685. [PMID: 35861925 PMCID: PMC9606181 DOI: 10.1007/s13311-022-01257-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2022] [Indexed: 10/17/2022] Open
Abstract
Depressed individuals who carry the short allele for the serotonin-transporter-linked promotor region of the gene are more vulnerable to stress and have reduced response to first-line antidepressants such as selective serotonin reuptake inhibitors. Since depression severity has been reported to correlate with brain iron levels, the present study aimed to characterise the potential antidepressant properties of the iron chelator deferiprone. Using the serotonin transporter knock-out (5-HTT KO) mouse model, we assessed the behavioural effects of acute deferiprone on the Porsolt swim test (PST) and novelty-suppressed feeding test (NSFT). Brain and blood iron levels were also measured following acute deferiprone. To determine the relevant brain regions activated by deferiprone, we then measured c-Fos expression and applied network-based analyses. We found that deferiprone reduced immobility time in the PST in 5-HTT KO mice and reduced latency to feed in the NSFT in both genotypes, suggesting potential antidepressant-like effects. There was no effect on brain or blood iron levels following deferiprone treatment, potentially indicating an acute iron-independent mechanism. Deferiprone reversed the increase in c-Fos expression induced by swim stress in 5-HTT KO mice in the lateral amygdala. Functional network analyses suggest that hub regions of activity in mice treated with deferiprone include the caudate putamen and prefrontal cortex. The PST-induced increase in network modularity in wild-type mice was not observed in 5-HTT KO mice. Altogether, our data show that the antidepressant-like effects of deferiprone could be acting via an iron-independent mechanism and that these therapeutic effects are underpinned by changes in neuronal activity in the lateral amygdala.
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Affiliation(s)
- Volkan Uzungil
- Melbourne Brain Centre, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia
| | - Harvey Tran
- Melbourne Brain Centre, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia
| | - Connor Aitken
- Melbourne Brain Centre, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia
| | - Carey Wilson
- Melbourne Brain Centre, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia
| | - Carlos M Opazo
- Melbourne Dementia Research Centre, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia
| | - Shanshan Li
- Melbourne Brain Centre, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia
| | - Jennyfer M Payet
- School of Psychology and Public Health, La Trobe University, Melbourne, VIC, 3086, Australia
| | - Celeste H Mawal
- Melbourne Dementia Research Centre, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia
| | - Ashley I Bush
- Melbourne Dementia Research Centre, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia
| | - Matthew W Hale
- School of Psychology and Public Health, La Trobe University, Melbourne, VIC, 3086, Australia
| | - Anthony J Hannan
- Melbourne Brain Centre, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia
- Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Australia
| | - Thibault Renoir
- Melbourne Brain Centre, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia.
- Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Australia.
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11
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Améndola L, Weary D, Zobel G. Effects of personality on assessments of anxiety and cognition. Neurosci Biobehav Rev 2022; 141:104827. [PMID: 35970418 DOI: 10.1016/j.neubiorev.2022.104827] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 07/10/2022] [Accepted: 08/10/2022] [Indexed: 11/17/2022]
Abstract
Individual variation in responses to commonly used tests of anxiety and spatial memory is often reported. While this variation is frequently considered to be 'noise', evidence suggests that it is, at least partially, related to consistent individual differences in behavioral responses (i.e., personality). The same tests used to assess anxiety are often used to profile personality traits, but personality differences are rarely considered when testing treatment differences in anxiety. Focusing on the rat literature, we describe fundamental principles involved in anxiety and spatial memory tests and we discuss how personality differences and housing conditions can influence behavioral responses in these tests. We propose that an opportunity exists to increase stress resiliency in environmentally sensitive individuals by providing environmental enrichment. We conclude by discussing different approaches to incorporating personality measures into the design and analysis of future studies; given the potential that variation masks research outcomes, we suggest that a strategy which considers the individual and its housing can contribute to improving research reproducibility.
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Affiliation(s)
- Lucia Améndola
- Animal Welfare Program, University of British Columbia, Canada.
| | - Daniel Weary
- Animal Welfare Program, University of British Columbia, Canada.
| | - Gosia Zobel
- Animal Behaviour and Welfare Team, AgResearch Ltd., Ruakura Research Centre, 10 Bisley Road, Private Bag 3123, Hamilton 3214, New Zealand.
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12
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Suresh P, Jasmin S, Yen Y, Hsu HJ, Varinthra P, Pairojana T, Chen CC, Liu IY. Attenuation of HECT-E3 ligase expression rescued memory deficits in 3xTg-AD mice. Front Aging Neurosci 2022; 14:916904. [PMID: 35966798 PMCID: PMC9372289 DOI: 10.3389/fnagi.2022.916904] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Accepted: 07/11/2022] [Indexed: 01/07/2023] Open
Abstract
Alzheimer's disease (AD) is one of the most common progressive neurodegenerative disorders that cause deterioration of cognitive functions. Recent studies suggested that the accumulation of inflammatory molecules and impaired protein degradation mechanisms might both play a critical role in the progression of AD. Autophagy is a major protein degradation pathway that can be controlled by several HECT-E3 ligases, which then regulates the expression of inflammatory molecules. E3 ubiquitin ligases are known to be upregulated in several neurodegenerative diseases. Here, we studied the expressional change of HECT-E3 ligase using M01 on autophagy and inflammasome pathways in the context of AD pathogenesis. Our results demonstrated that the M01 treatment reversed the working memory deficits in 3xTg-AD mice when examined with the T-maze and reversal learning with the Morris water maze. Additionally, the electrophysiology recordings indicated that M01 treatment enhanced the long-term potentiation in the hippocampus of 3xTg-AD mice. Together with the improved memory performance, the expression levels of the NLRP3 inflammasome protein were decreased. On the other hand, autophagy-related molecules were increased in the hippocampus of 3xTg-AD mice. Furthermore, the protein docking analysis indicated that the binding affinity of M01 to the WWP1 and NEDD4 E3 ligases was the highest among the HECT family members. The western blot analysis also confirmed the decreased expression level of NEDD4 protein in the M01-treated 3xTg-AD mice. Overall, our results demonstrate that the modulation of HECT-E3 ligase expression level can be used as a strategy to treat early memory deficits in AD by decreasing NLRP3 inflammasome molecules and increasing the autophagy pathway.
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Affiliation(s)
- Pavithra Suresh
- Institute of Medical Sciences, Tzu Chi University, Hualien City, Taiwan
| | - Sureka Jasmin
- Department of Molecular Biology and Human Genetics, Tzu Chi University, Hualien City, Taiwan
| | - Yun Yen
- Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei City, Taiwan
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei City, Taiwan
- TMU Research Center of Cancer Translational Medicine, Taipei Medical University, Taipei City, Taiwan
- Cancer Center, Taipei Municipal WanFang Hospital, Taipei City, Taiwan
- Center for Cancer Translational Research, Tzu Chi University, Hualien City, Taiwan
| | - Hao-Jen Hsu
- Department of Life Sciences, Tzu Chi University, Hualien City, Taiwan
| | | | - Tanita Pairojana
- Institute of Medical Sciences, Tzu Chi University, Hualien City, Taiwan
| | - Chien-Chang Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei City, Taiwan
| | - Ingrid Y. Liu
- Institute of Medical Sciences, Tzu Chi University, Hualien City, Taiwan
- *Correspondence: Ingrid Y. Liu
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13
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Social Fear Affects Limbic System Neuronal Activity and Gene Expression. Int J Mol Sci 2022; 23:ijms23158228. [PMID: 35897794 PMCID: PMC9367789 DOI: 10.3390/ijms23158228] [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] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 07/22/2022] [Accepted: 07/23/2022] [Indexed: 01/04/2023] Open
Abstract
Social anxiety disorder (SAD) is a highly prevalent and comorbid anxiety disorder with rather unclear underlying mechanisms. Here, we aimed to characterize neurobiological changes occurring in mice expressing symptoms of social fear and to identify possible therapeutic targets for SAD. Social fear was induced via social fear conditioning (SFC), a validated animal model of SAD. We assessed the expression levels of the immediate early genes (IEGs) cFos, Fosl2 and Arc as markers of neuronal activity and the expression levels of several genes of the GABAergic, serotoninergic, oxytocinergic, vasopressinergic and neuropeptide Y (NPY)-ergic systems in brain regions involved in social behavior or fear-related behavior in SFC+ and SFC− mice 2 h after exposure to a conspecific. SFC+ mice showed a decreased number and density of cFos-positive cells and decreased expression levels of IEGs in the dorsal hippocampus. SFC+ mice also showed alterations in the expression of NPY and serotonin system-related genes in the paraventricular nucleus of the hypothalamus, basolateral amygdala, septum and dorsal raphe nucleus, but not in the dorsal hippocampus. Our results describe neuronal alterations occurring during the expression of social fear and identify the NPY and serotonergic systems as possible targets in the treatment of SAD.
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14
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Delli Colli C, Borgi M, Poggini S, Chiarotti F, Cirulli F, Penninx BWJH, Benedetti F, Vai B, Branchi I. Time moderates the interplay between 5-HTTLPR and stress on depression risk: gene x environment interaction as a dynamic process. Transl Psychiatry 2022; 12:274. [PMID: 35821204 PMCID: PMC9276704 DOI: 10.1038/s41398-022-02035-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 06/13/2022] [Accepted: 06/27/2022] [Indexed: 12/02/2022] Open
Abstract
The serotonin-transporter-linked promoter region (5-HTTLPR) has been widely investigated as contributing to depression vulnerability. Nevertheless, empirical research provides wide contrasting findings regarding its involvement in the etiopathogenesis of the disorder. Our hypothesis was that such discrepancy can be explained considering time as moderating factor. We explored this hypothesis, exploiting a meta analytic approach. We searched PubMed, PsychoINFO, Scopus and EMBASE databases and 1096 studies were identified and screened, resulting in 22 studies to be included in the meta-analyses. The effect of the 5-HTTLPR x stress interaction on depression risk was found to be moderated by the following temporal factors: the duration of stress (i.e. chronic vs. acute) and the time interval between end of stress and assessment of depression (i.e. within 1 year vs. more than 1 year). When stratifying for the duration of stress, the effect of the 5-HTTLPR x stress interaction emerged only in the case of chronic stress, with a significant subgroup difference (p = 0.004). The stratification according to time interval revealed a significant interaction only for intervals within 1 year, though no difference between subgroups was found. The critical role of time interval clearly emerged when considering only chronic stress: a significant effect of the 5-HTTLPR and stress interaction was confirmed exclusively within 1 year and a significant subgroup difference was found (p = 0.01). These results show that the 5-HTTLPR x stress interaction is a dynamic process, producing different effects at different time points, and indirectly confirm that s-allele carriers are both at higher risk and more capable to recover from depression. Overall, these findings expand the current view of the interplay between 5-HTTLPR and stress adding the temporal dimension, that results in a three-way interaction: gene x environment x time.
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Affiliation(s)
- Claudia Delli Colli
- grid.416651.10000 0000 9120 6856Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, Rome, Italy ,grid.7841.aPhD program in Pharmacology and Toxicology, Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, Rome, Italy
| | - Marta Borgi
- grid.416651.10000 0000 9120 6856Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, Rome, Italy
| | - Silvia Poggini
- grid.416651.10000 0000 9120 6856Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, Rome, Italy
| | - Flavia Chiarotti
- grid.416651.10000 0000 9120 6856Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, Rome, Italy
| | - Francesca Cirulli
- grid.416651.10000 0000 9120 6856Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, Rome, Italy
| | - Brenda W. J. H. Penninx
- grid.12380.380000 0004 1754 9227Department of Psychiatry, Amsterdam UMC, Vrije Universiteit, Amsterdam, The Netherlands
| | - Francesco Benedetti
- grid.18887.3e0000000417581884Psychiatry & Clinical Psychobiology, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy ,grid.15496.3f0000 0001 0439 0892Università Vita-Salute San Raffaele, Milan, Italy
| | - Benedetta Vai
- grid.18887.3e0000000417581884Psychiatry & Clinical Psychobiology, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy ,grid.15496.3f0000 0001 0439 0892Università Vita-Salute San Raffaele, Milan, Italy
| | - Igor Branchi
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, Rome, Italy.
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15
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Wert-Carvajal C, Reneaux M, Tchumatchenko T, Clopath C. Dopamine and serotonin interplay for valence-based spatial learning. Cell Rep 2022; 39:110645. [PMID: 35417691 DOI: 10.1016/j.celrep.2022.110645] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 10/31/2021] [Accepted: 03/17/2022] [Indexed: 11/17/2022] Open
Abstract
Dopamine (DA) and serotonin (5-HT) are important neuromodulators of synaptic plasticity that have been linked to learning from positive or negative outcomes or valence-based learning. In the hippocampus, both affect long-term plasticity but play different roles in encoding uncertainty or predicted reward. DA has been related to positive valence, from reward consumption or avoidance behavior, and 5-HT to aversive encoding. We propose DA produces overall LTP while 5-HT elicits LTD. Here, we compare two reward-modulated spike timing-dependent plasticity (R-STDP) rules to describe the action of these neuromodulators. We examined their role in cognitive performance and flexibility for computational models of the Morris water maze task and reversal learning. Our results show that the interplay of DA and 5-HT improves learning performance and can explain experimental evidence. This study reinforces the importance of neuromodulation in determining the direction of plasticity.
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Affiliation(s)
- Carlos Wert-Carvajal
- Bioengineering Department, Imperial College London, London SW7 2AZ, UK; Theory of Neural Dynamics Group, Max Planck Institute for Brain Research, 60438 Frankfurt, Germany; Institute of Experimental Epileptology and Cognition Research, Life and Brain Center, University of Bonn Medical Center, 53127 Bonn, Germany
| | - Melissa Reneaux
- Bioengineering Department, Imperial College London, London SW7 2AZ, UK
| | - Tatjana Tchumatchenko
- Theory of Neural Dynamics Group, Max Planck Institute for Brain Research, 60438 Frankfurt, Germany; Institute of Experimental Epileptology and Cognition Research, Life and Brain Center, University of Bonn Medical Center, 53127 Bonn, Germany; Institute of Physiological Chemistry, University of Mainz Medical Center, 55131 Mainz, Germany.
| | - Claudia Clopath
- Bioengineering Department, Imperial College London, London SW7 2AZ, UK.
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16
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Wang X, Wang K, Wu X, Huang W, Yang L. Role of the cAMP-PKA-CREB-BDNF pathway in abnormal behaviours of serotonin transporter knockout mice. Behav Brain Res 2022; 419:113681. [PMID: 34838579 DOI: 10.1016/j.bbr.2021.113681] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 11/16/2021] [Accepted: 11/19/2021] [Indexed: 11/02/2022]
Abstract
Serotonin transporter gene-linked polymorphic region polymorphisms are associated with anxiety, neuroticism, affective disorders and vulnerability to stressful life events; however, the relevant physiological mechanisms are not well understood. Serotonin transporter knockout mice have been widely used as a model of allelic variation of serotonin transporter function in humans; herein, wild-type mice and heterozygous and homozygous knockout mice models were established to explore the behavioural changes related to different genotypes and the possible physiological mechanisms. Behavioural changes were assessed using behavioural tests, namely, elevated plus maze, open field, Morris water maze and rotarod tests. Serum indicators were detected using the enzyme-linked immunosorbent assay. Compared with wild-type mice, homozygous mice showed significant anxiety-like behaviours in the plus maze and open field tests; conversely, anxiety-like behaviours in heterozygous mice were less pronounced. Homozygous mice also showed cognitive impairment and motor inhibition in the Morris water maze and rotarod tests. Serotonin levels decreased in both heterozygous and homozygous mice, and 5-hydroxytryptophan, protein kinase A, adenylyl cyclase, cyclic adenosine monophosphate response element-binding protein and brain-derived neurotrophic factor levels were lower in homozygous mice than in wild-type and heterozygous mice, whereas no statistical differences were found between wild-type and heterozygous mice. Additionally, there was a correlation between serological and behavioural indicators. This study provided experimental evidence that the cyclic adenosine monophosphate-protein kinase A-cyclic adenosine monophosphate response element-binding protein-brain-derived neurotrophic factor pathway may be involved in the regulation of polymorphism to stress and enriched the behavioural and physiological characteristics of serotonin transporter knockout mice.
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Affiliation(s)
- Xiaomin Wang
- Department of Epidemiology and Health Statistics, School of Public Health, Guangxi Medical University, Nanning, PR China
| | - Ke Wang
- Department of Occupational and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, PR China
| | - Xiangmin Wu
- Department of Occupational and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, PR China
| | - Wenxiu Huang
- Department of Occupational and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, PR China
| | - Li Yang
- Department of Occupational and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, PR China.
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17
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Popp S, Schmitt-Böhrer A, Langer S, Hofmann U, Hommers L, Schuh K, Frantz S, Lesch KP, Frey A. 5-HTT Deficiency in Male Mice Affects Healing and Behavior after Myocardial Infarction. J Clin Med 2021; 10:jcm10143104. [PMID: 34300270 PMCID: PMC8308004 DOI: 10.3390/jcm10143104] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 07/09/2021] [Accepted: 07/12/2021] [Indexed: 12/13/2022] Open
Abstract
Anxiety disorders and depression are common comorbidities in cardiac patients. Mice lacking the serotonin transporter (5-HTT) exhibit increased anxiety-like behavior. However, the role of 5-HTT deficiency on cardiac aging, and on healing and remodeling processes after myocardial infarction (MI), remains unclear. Cardiological evaluation of experimentally naïve male mice revealed a mild cardiac dysfunction in ≥4-month-old 5-HTT knockout (−/−) animals. Following induction of chronic cardiac dysfunction (CCD) by MI vs. sham operation 5-HTT−/− mice with infarct sizes >30% experienced 100% mortality, while 50% of 5-HTT+/− and 37% of 5-HTT+/+ animals with large MI survived the 8-week observation period. Surviving (sham and MI < 30%) 5-HTT−/− mutants displayed reduced exploratory activity and increased anxiety-like behavior in different approach-avoidance tasks. However, CCD failed to provoke a depressive-like behavioral response in either 5-Htt genotype. Mechanistic analyses were performed on mice 3 days post-MI. Electrocardiography, histology and FACS of inflammatory cells revealed no abnormalities. However, gene expression of inflammation-related cytokines (TGF-β, TNF-α, IL-6) and MMP-2, a protein involved in the breakdown of extracellular matrix, was significantly increased in 5-HTT−/− mice after MI. This study shows that 5-HTT deficiency leads to age-dependent cardiac dysfunction and disrupted early healing after MI probably due to alterations of inflammatory processes in mice.
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Affiliation(s)
- Sandy Popp
- Comprehensive Heart Failure Center, University Hospital of Würzburg, 97078 Würzburg, Germany; (S.P.); (S.L.); (U.H.); (S.F.); (K.-P.L.)
- Center of Mental Health, Department of Psychiatry, Psychosomatics and Psychotherapy, Division of Molecular Psychiatry, University Hospital of Würzburg, 97080 Würzburg, Germany
| | - Angelika Schmitt-Böhrer
- Center of Mental Health, Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, 97080 Würzburg, Germany; (A.S.-B.); (L.H.)
| | - Simon Langer
- Comprehensive Heart Failure Center, University Hospital of Würzburg, 97078 Würzburg, Germany; (S.P.); (S.L.); (U.H.); (S.F.); (K.-P.L.)
| | - Ulrich Hofmann
- Comprehensive Heart Failure Center, University Hospital of Würzburg, 97078 Würzburg, Germany; (S.P.); (S.L.); (U.H.); (S.F.); (K.-P.L.)
- Medical Clinic and Policlinic I, University Hospital of Würzburg, 97080 Würzburg, Germany
- Interdisciplinary Center for Clinical Research, University Hospital of Würzburg, 97080 Würzburg, Germany
| | - Leif Hommers
- Center of Mental Health, Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, 97080 Würzburg, Germany; (A.S.-B.); (L.H.)
- Interdisciplinary Center for Clinical Research, University Hospital of Würzburg, 97080 Würzburg, Germany
| | - Kai Schuh
- Institute of Physiology I, University of Würzburg, 97070 Würzburg, Germany;
| | - Stefan Frantz
- Comprehensive Heart Failure Center, University Hospital of Würzburg, 97078 Würzburg, Germany; (S.P.); (S.L.); (U.H.); (S.F.); (K.-P.L.)
- Medical Clinic and Policlinic I, University Hospital of Würzburg, 97080 Würzburg, Germany
| | - Klaus-Peter Lesch
- Comprehensive Heart Failure Center, University Hospital of Würzburg, 97078 Würzburg, Germany; (S.P.); (S.L.); (U.H.); (S.F.); (K.-P.L.)
- Center of Mental Health, Department of Psychiatry, Psychosomatics and Psychotherapy, Division of Molecular Psychiatry, University Hospital of Würzburg, 97080 Würzburg, Germany
- Center of Mental Health, Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, 97080 Würzburg, Germany; (A.S.-B.); (L.H.)
- Department of Translational Neuroscience, School for Mental Health and Neuroscience, Maastricht University, 6229 Maastricht, The Netherlands
- Laboratory of Psychiatric Neurobiology, Institute of Molecular Medicine, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | - Anna Frey
- Comprehensive Heart Failure Center, University Hospital of Würzburg, 97078 Würzburg, Germany; (S.P.); (S.L.); (U.H.); (S.F.); (K.-P.L.)
- Medical Clinic and Policlinic I, University Hospital of Würzburg, 97080 Würzburg, Germany
- Interdisciplinary Center for Clinical Research, University Hospital of Würzburg, 97080 Würzburg, Germany
- Correspondence: ; Tel.: +49-931-201-39927
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18
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Wilson C, Rogers J, Chen F, Li S, Adlard PA, Hannan AJ, Renoir T. Exercise ameliorates aberrant synaptic plasticity without enhancing adult-born cell survival in the hippocampus of serotonin transporter knockout mice. Brain Struct Funct 2021; 226:1991-1999. [PMID: 34052925 DOI: 10.1007/s00429-021-02283-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 04/21/2021] [Indexed: 12/28/2022]
Abstract
Deficits in hippocampal cellular and synaptic plasticity are frequently associated with cognitive and mood disorders, and indeed common mechanisms of antidepressants are thought to involve neuroplastic processes. Here, we investigate hippocampal adult-born cell survival and synaptic plasticity (long-term potentiation, LTP, and long-term depression, LTD) in serotonin transporter (5-HTT) knockout (KO) mice. From 8 weeks of age, mice either continued in standard-housing conditions or were given access to voluntary running wheels for 1 month. Electrophysiology was performed on hippocampal slices to measure LTP and LTD, and immunohistochemistry was used to assess cell proliferation and subsequent survival in the dentate gyrus. The results revealed a reduced LTP in 5-HTT KO mice that was restored to wild-type (WT) levels after chronic exercise. While LTD appeared normal in 5-HTT KO, exercise decreased the magnitude of LTD in both WT and 5-HTT KO mice. Furthermore, although 5-HTT KO mice had normal hippocampal adult-born cell survival, they did not benefit from the pro-proliferative effects of exercise observed in WT animals. Taken together, these findings suggest that reduced 5-HTT expression is associated with significant alterations to functional neuroplasticity. Interestingly, 5-HTT appeared necessary for exercise-induced augmentation of adult-born hippocampal cell survival, yet exercise corrected the LTP impairment displayed by 5-HTT KO mice. Together, our findings further highlight the salience of serotonergic signalling in mediating the neurophysiological benefits of exercise.
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Affiliation(s)
- Carey Wilson
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Melbourne, VIC, 3010, Australia
| | - Jake Rogers
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Melbourne, VIC, 3010, Australia
| | - Feng Chen
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Melbourne, VIC, 3010, Australia
| | - Shanshan Li
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Melbourne, VIC, 3010, Australia
| | - Paul A Adlard
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Melbourne, VIC, 3010, Australia.,Melbourne Dementia Research Centre, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Australia
| | - Anthony J Hannan
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Melbourne, VIC, 3010, Australia.,Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Melbourne, Australia
| | - Thibault Renoir
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Melbourne, VIC, 3010, Australia. .,Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Melbourne, Australia.
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19
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Murayama MA, Arimitsu N, Shimizu J, Fujiwara N, Takai K, Ikeda Y, Okada Y, Hirotsu C, Takada E, Suzuki T, Suzuki N. Female dominance of both spatial cognitive dysfunction and neuropsychiatric symptoms in a mouse model of Alzheimer's disease. Exp Anim 2021; 70:398-405. [PMID: 33840703 PMCID: PMC8390308 DOI: 10.1538/expanim.21-0009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Alzheimer’s disease (AD) is a prevalent neurological disorder affecting memory function in elderly persons. Indeed, AD exhibits abnormality in cognitive
behaviors and higher susceptibility to neuropsychiatric symptoms (NPS). Various factors including aging, sex difference and NPS severity, are implicated during
in development of AD. In this study, we evaluated behavioral abnormalities of AD model, PDAPP transgenic mice at young age using the Morris Water Maze test,
which was established to assess hippocampal-dependent learning and memory. We found that female AD model mice exhibited spatial learning dysfunction and highly
susceptible to NPS such as anxiety and depression, whereas spatial reference memory function was comparable in female PDAPP Tg mice to female wild type (WT)
mice. Spatial learning function was comparable in male AD model mice to male WT mice. Multiple regression analysis showed that spatial learning dysfunction was
associated with NPS severity such as anxiety and depression. Furthermore, the analysis showed that spatial reference memory function was associated with status
of depression, but not anxiety. Thus, these results suggest female dominance of spatial learning dysfunction in the AD model mice accompanying increased NPS
severity. The understandings of AD model may be useful for the development of therapeutic agents and methods in human AD.
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Affiliation(s)
- Masanori A Murayama
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.,Present address: Department of Animal Models for Human Diseases, Institute of Biomedical Science, Kansai Medical University, 2-5-1 Shinmachi, Hirakata, Osaka 573-1010, Japan
| | - Nagisa Arimitsu
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Jun Shimizu
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Naruyoshi Fujiwara
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Kenji Takai
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Yoshiki Ikeda
- Department of Molecular Genetics, Institute of Biomedical Science, Kansai Medical University, 2-5-1 Shinmachi, Hirakata, Osaka 573-1010, Japan
| | - Yoko Okada
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Chieko Hirotsu
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Erika Takada
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Tomoko Suzuki
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Noboru Suzuki
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
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20
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Murayama MA, Arimitsu N, Shimizu J, Fujiwara N, Takai K, Okada Y, Hirotsu C, Takada E, Suzuki T, Suzuki N. Dementia model mice exhibited improvements of neuropsychiatric symptoms as well as cognitive dysfunction with neural cell transplantation. Exp Anim 2021; 70:387-397. [PMID: 33828024 PMCID: PMC8390309 DOI: 10.1538/expanim.21-0008] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Elderly patients with dementia suffer from cognitive dysfunctions and neuropsychiatric symptoms (NPS) such as anxiety and depression. Alzheimer’s disease (AD)
is a form of age-related dementia, and loss of cholinergic neurons is intimately associated with development of AD symptoms. We and others have reported that
neural cell transplantation ameliorated cognitive dysfunction in AD model mice. It remains largely unclear whether neural cell transplantation ameliorates the
NPS of AD. It would be interesting to determine whether NPS correlates with cognitive dysfunctions before and after neural cell transplantation in AD model
mice. Based on the revalidation of our previous data from a Morris water maze test, we found that neural cell transplantation improved anxiety and depression
significantly and marginally affected locomotion activity in AD mice. A correlation analysis revealed that the spatial learning function of AD mice was
correlated with their NPS scores both before and after cell transplantation in a similar manner. In contrast, in the mice subjected to cell transplantation,
spatial reference memory function was not correlated with NPS scores. These results suggested the neural cell transplantation in the AD model mice significantly
improved NPS to the same degree as cognitive dysfunctions, possibly via distinct mechanisms, such as the cholinergic and GABAergic systems.
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Affiliation(s)
- Masanori A Murayama
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.,Present address: Department of Animal Models for Human Diseases, Institute of Biomedical Science, Kansai Medical University, 2-5-1 Shinmachi, Hirakata, Osaka 573-1010, Japan
| | - Nagisa Arimitsu
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Jun Shimizu
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Naruyoshi Fujiwara
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Kenji Takai
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Yoko Okada
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Chieko Hirotsu
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Erika Takada
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Tomoko Suzuki
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | - Noboru Suzuki
- Department of Immunology and Medicine, St. Marianna University of School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
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21
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Kolter JF, Hildenbrand MF, Popp S, Nauroth S, Bankmann J, Rother L, Waider J, Deckert J, Asan E, Jakob PM, Lesch KP, Schmitt-Böhrer A. Serotonin transporter genotype modulates resting state and predator stress-induced amygdala perfusion in mice in a sex-dependent manner. PLoS One 2021; 16:e0247311. [PMID: 33606835 PMCID: PMC7895400 DOI: 10.1371/journal.pone.0247311] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 02/04/2021] [Indexed: 12/16/2022] Open
Abstract
The serotonin transporter (5-HTT) is a key molecule of serotoninergic neurotransmission and target of many anxiolytics and antidepressants. In humans, 5-HTT gene variants resulting in lower expression levels are associated with behavioral traits of anxiety. Furthermore, functional magnetic resonance imaging (fMRI) studies reported increased cerebral blood flow (CBF) during resting state (RS) and amygdala hyperreactivity. 5-HTT deficient mice as an established animal model for anxiety disorders seem to be well suited for investigating amygdala (re-)activity in an fMRI study. We investigated wildtype (5-HTT+/+), heterozygous (5-HTT+/-), and homozygous 5-HTT-knockout mice (5-HTT-/-) of both sexes in an ultra-high-field 17.6 Tesla magnetic resonance scanner. CBF was measured with continuous arterial spin labeling during RS, stimulation state (SS; with odor of rats as aversive stimulus), and post-stimulation state (PS). Subsequently, post mortem c-Fos immunohistochemistry elucidated neural activation on cellular level. The results showed that in reaction to the aversive odor CBF in total brain and amygdala of all mice significantly increased. In male 5-HTT+/+ mice amygdala RS CBF levels were found to be significantly lower than in 5-HTT+/- mice. From RS to SS 5-HTT+/+ amygdala perfusion significantly increased compared to both 5-HTT+/- and 5-HTT-/- mice. Perfusion level changes of male mice correlated with the density of c-Fos-immunoreactive cells in the amygdaloid nuclei. In female mice the perfusion was not modulated by the 5-Htt-genotype, but by estrous cycle stages. We conclude that amygdala reactivity is modulated by the 5-Htt genotype in males. In females, gonadal hormones have an impact which might have obscured genotype effects. Furthermore, our results demonstrate experimental support for the tonic model of 5-HTTLPR function.
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Affiliation(s)
- Jann F. Kolter
- Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany
- Division of Molecular Psychiatry, Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany
| | - Markus F. Hildenbrand
- Department of Magnetic Resonance and X-Ray Imaging, Fraunhofer Development Center X-Ray Technology, Wuerzburg, Germany
| | - Sandy Popp
- Division of Molecular Psychiatry, Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany
| | - Stephan Nauroth
- Division of Molecular Psychiatry, Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany
| | - Julian Bankmann
- Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany
| | - Lisa Rother
- Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany
| | - Jonas Waider
- Division of Molecular Psychiatry, Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany
| | - Jürgen Deckert
- Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany
| | - Esther Asan
- Institute of Anatomy and Cell Biology, University of Wuerzburg, Wuerzburg, Germany
| | - Peter M. Jakob
- Department of Experimental Physics 5, University of Wuerzburg, Wuerzburg, Germany
| | - Klaus-Peter Lesch
- Division of Molecular Psychiatry, Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany
| | - Angelika Schmitt-Böhrer
- Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany
- * E-mail:
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22
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Leibold NK, van den Hove DLA, Weidner MT, Buchanan GF, Steinbusch HWM, Lesch KP, Schruers KRJ. Effect of serotonin transporter genotype on carbon dioxide-induced fear-related behavior in mice. J Psychopharmacol 2020; 34:1408-1417. [PMID: 33103571 PMCID: PMC7708670 DOI: 10.1177/0269881120959611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Inhaling 35% carbon dioxide induces an emotional and symptomatic state in humans closely resembling naturally occurring panic attacks, the core symptom of panic disorder. Previous research has suggested a role of the serotonin system in the individual sensitivity to carbon dioxide. In line with this, we previously showed that a variant in the SLC6A4 gene, encoding the serotonin transporter, moderates the fear response to carbon dioxide in humans. To study the etiological basis of carbon dioxide-reactivity and panic attacks in more detail, we recently established a translational mouse model. AIM The purpose of this study was to investigate whether decreased expression of the serotonin transporter affects the sensitivity to carbon dioxide. METHODS Based on our previous work, wildtype and serotonin transporter deficient (+/-, -/-) mice were monitored while being exposed to carbon dioxide-enriched air. In wildtype and serotonin transporter +/- mice, also cardio-respiration was assessed. RESULTS For most behavioral measures under air exposure, wildtype and serotonin transporter +/- mice did not differ, while serotonin transporter -/- mice showed more fear-related behavior. Carbon dioxide exposure evoked a marked increase in fear-related behaviors, independent of genotype, with the exception of time serotonin transporter -/- mice spent in the center zone of the modified open field test and freezing in the two-chamber test. On the physiological level, when inhaling carbon dioxide, the respiratory system was strongly activated and heart rate decreased independent of genotype. CONCLUSION Carbon dioxide is a robust fear-inducing stimulus. It evokes inhibitory behavioral responses such as decreased exploration and is associated with a clear respiratory profile independent of serotonin transporter genotype.
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Affiliation(s)
- Nicole K Leibold
- Department of Psychiatry and Neuropsychology, Maastricht University, Maastricht, The Netherlands,Department of Neurology, Yale School of Medicine, New Haven, USA,Nicole K Leibold, Department of Psychiatry and Neuropsychology, Maastricht University, P.O. Box 616 (Vijverdal), 6200 MD Maastricht, The Netherlands.
| | - Daniel LA van den Hove
- Department of Psychiatry and Neuropsychology, Maastricht University, Maastricht, The Netherlands,School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands,Division of Molecular Psychiatry, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany
| | - Magdalena T Weidner
- Department of Psychiatry and Neuropsychology, Maastricht University, Maastricht, The Netherlands,School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands,Division of Molecular Psychiatry, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany,Department of Psychiatry and Psychotherapy, Medical Center University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Gordon F Buchanan
- Department of Neurology, Yale School of Medicine, New Haven, USA,Department of Neurology, University of Iowa, Iowa City, USA,University of Iowa Graduate College, Iowa City, USA
| | - Harry WM Steinbusch
- Department of Psychiatry and Neuropsychology, Maastricht University, Maastricht, The Netherlands,School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands,Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technoglogy (DGIST), Daegu, South Korea
| | - Klaus-Peter Lesch
- Department of Psychiatry and Neuropsychology, Maastricht University, Maastricht, The Netherlands,School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands,Division of Molecular Psychiatry, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany,Laboratory of Psychiatric Neurobiology, I.M. Sechenov First Moscow State Medical University, Moscow, Russia
| | - Koen RJ Schruers
- Department of Psychiatry and Neuropsychology, Maastricht University, Maastricht, The Netherlands,School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands,Department of Psychology, University of Leuven, Leuven, Belgium
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23
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Mercerón-Martínez D, Almaguer-Melian W, Alberti-Amador E, Calderón-Peña R, Bergado JA. Amygdala stimulation ameliorates memory impairments and promotes c-Fos activity in fimbria-fornix-lesioned rats. Synapse 2020; 74:e22179. [PMID: 32621298 DOI: 10.1002/syn.22179] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 06/10/2020] [Accepted: 06/26/2020] [Indexed: 11/08/2022]
Abstract
Recently we provided data showing that amygdala stimulation can ameliorate spatial memory impairments in rats with lesion in the fimbria-fornix (FF). The mechanisms for this improvement involve early gene expression and synthesis of BDNF, MAP-2, and GAP43 in the hippocampus and prefrontal cortex. Now we have studied which brain structures are activated by the amygdala using c-Fos as a marker of neural activation. First, we studied neuronal activation after tetanic stimulation to the amygdala in intact rats. We then carried out a second study in FF-lesioned rats in which the amygdala was stimulated 15 min after daily spatial memory training in the water maze. Our results showed that amygdala stimulation produces widespread brain activation, that includes cortical, thalamic, and brain stem structures. Activation was particularly intense in the dentate gyrus and the prefrontal cortex. Training in the water maze increased c-Fos positive nuclei in the dentate gyrus of the hippocampus and in medial prefrontal cortex. Amygdala stimulation to trained FF-lesioned rats induced an increase of neural activity in the dentate gyrus and medial prefrontal cortex relative to the FF-lesioned, but not stimulated group, like the c-Fos activity seen in trained control rats. Based on these and previous results we explain the mechanisms of amygdala reinforcement of neural plasticity and the partial recovery of spatial memory deficits.
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Affiliation(s)
- Daymara Mercerón-Martínez
- Department of Experimental Neurophysiology, International Center for Neurological Restoration (CIREN), Havana, Cuba
| | - William Almaguer-Melian
- Department of Experimental Neurophysiology, International Center for Neurological Restoration (CIREN), Havana, Cuba
| | - Esteban Alberti-Amador
- Department of Experimental Neurophysiology, International Center for Neurological Restoration (CIREN), Havana, Cuba
| | | | - Jorge A Bergado
- Universidad del Sinú "Elías Bechara Zainum", Montería, Colombia
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24
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Fesharaki-Zadeh A, Miyauchi JT, St. Laurent-Arriot K, Tsirka SE, Bergold PJ. Increased Behavioral Deficits and Inflammation in a Mouse Model of Co-Morbid Traumatic Brain Injury and Post-Traumatic Stress Disorder. ASN Neuro 2020; 12:1759091420979567. [PMID: 33342261 PMCID: PMC7755938 DOI: 10.1177/1759091420979567] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 11/03/2020] [Accepted: 11/08/2020] [Indexed: 01/21/2023] Open
Abstract
Comorbid post-traumatic stress disorder with traumatic brain injury (TBI) produce more severe affective and cognitive deficits than PTSD or TBI alone. Both PTSD and TBI produce long-lasting neuroinflammation, which may be a key underlying mechanism of the deficits observed in co-morbid TBI/PTSD. We developed a model of co-morbid TBI/PTSD by combining the closed head (CHI) model of TBI with the chronic variable stress (CVS) model of PTSD and examined multiple behavioral and neuroinflammatory outcomes. Male C57/Bl6 mice received sham treatment, CHI, CVS, CHI then CVS (CHI → CVS) or CVS then CHI (CVS → CHI). The CVS → CHI group had deficits in Barnes maze or active place avoidance not seen in the other groups. The CVS → CHI, CVS and CHI → CVS groups displayed increased basal anxiety level, based on performance on elevated plus maze. The CVS → CHI had impaired performance on Barnes Maze, and Active Place Avoidance. These performance deficits were strongly correlated with increased hippocampal Iba-1 level an indication of activated MP/MG. These data suggest that greater cognitive deficits in the CVS → CHI group were due to increased inflammation. The increased deficits and neuroinflammation in the CVS → CHI group suggest that the order by which a subject experiences TBI and PTSD is a major determinant of the outcome of brain injury in co-morbid TBI/PTSD.
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Affiliation(s)
- Arman Fesharaki-Zadeh
- Department of Psychiatry, State University of New York, Downstate Medical Center, Brooklyn, New York
| | - Jeremy T. Miyauchi
- Department of Physiology, State University of New York, Downstate Medical Center, Brooklyn, New York
| | - Karrah St. Laurent-Arriot
- Department of Pharmacology, State University of New York, Downstate Medical Center, Brooklyn, New York
| | - Stella E. Tsirka
- Department of Physiology, State University of New York, Downstate Medical Center, Brooklyn, New York
| | - Peter J. Bergold
- Department of Pharmacology, State University of New York, Downstate Medical Center, Brooklyn, New York
- Department of Neurology, State University of New York, Downstate Medical Center, Brooklyn, New York
- Department of Pharmacological Sciences, Stony Brook Medicine, Stony Brook University, Stony Brook, New York
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25
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Foltran RB, Stefani KM, Bonafina A, Resasco A, Diaz SL. Differential Hippocampal Expression of BDNF Isoforms and Their Receptors Under Diverse Configurations of the Serotonergic System in a Mice Model of Increased Neuronal Survival. Front Cell Neurosci 2019; 13:384. [PMID: 31555094 PMCID: PMC6712164 DOI: 10.3389/fncel.2019.00384] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 08/06/2019] [Indexed: 12/14/2022] Open
Abstract
Neurotrophic factors are relevant regulators of the neurogenic process at different levels. In particular, the brain-derived neurotrophic factor, BDNF, is highly expressed in the hippocampus (HC) of rodents and participates in the control of neuronal proliferation, and survival in the dentate gyrus (DG). Likewise, serotonin is also involved in the regulation of neurogenesis, though its role is apparently more complex. Indeed, both enhancement of serotonin neurotransmission as well as serotonin depletion, paradoxically increase neuronal survival in the HC of mice. In this study, we analyzed the protein expression of the BDNF isoforms, i.e., pro- and mature-BDNF, and their respective receptors p75 and TrkB, in the HC of mice chronically treated with para-chloro-phenyl-alanine (PCPA), an inhibitor of serotonin synthesis. The same analysis was conducted in hyposerotonergic mice with concomitant administration of the 5-HT1A receptor agonist, 8-Hydroxy-2-(di-n- propylamino) tetralin (8-OH-DPAT). Increased expression of p75 receptor with decreased expression of pro-BDNF was observed after chronic PCPA. Seven-day treatment with 8-OH-DPAT reestablished the expression of pro-BDNF modified by PCPA, and induced an increase in the expression of p75 receptor. It has been demonstrated that PCPA-treated mice have higher number of immature neurons in the HC. Given that immature neurons participate in the pattern separation process, the object pattern separation test was conducted. A better performance of hyposerotonergic mice was not confirmed in this assay. Altogether, our results show that molecules in the BDNF signaling pathway are differentially expressed under diverse configurations of the serotonergic system, allowing for fine-tuning of the neurogenic process.
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Affiliation(s)
- Rocío Beatriz Foltran
- Instituto de Biología Celular y Neurociencia Prof. E. De Robertis, CONICET - Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Karen Melany Stefani
- Instituto de Biología Celular y Neurociencia Prof. E. De Robertis, CONICET - Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Antonela Bonafina
- Instituto de Biología Celular y Neurociencia Prof. E. De Robertis, CONICET - Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Agustina Resasco
- Instituto de Biología Celular y Neurociencia Prof. E. De Robertis, CONICET - Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Silvina Laura Diaz
- Instituto de Biología Celular y Neurociencia Prof. E. De Robertis, CONICET - Universidad de Buenos Aires, Buenos Aires, Argentina
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26
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Rogers J, Chen F, Stanic D, Farzana F, Li S, Zeleznikow-Johnston AM, Nithianantharajah J, Churilov L, Adlard PA, Lanfumey L, Hannan AJ, Renoir T. Paradoxical effects of exercise on hippocampal plasticity and cognition in mice with a heterozygous null mutation in the serotonin transporter gene. Br J Pharmacol 2019; 176:3279-3296. [PMID: 31167040 DOI: 10.1111/bph.14760] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 05/08/2019] [Accepted: 05/14/2019] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Exercise is known to improve cognitive function, but the exact synaptic and cellular mechanisms remain unclear. We investigated the potential role of the serotonin (5-HT) transporter (SERT) in mediating these effects. EXPERIMENTAL APPROACH Hippocampal long-term potentiation (LTP) and neurogenesis were measured in standard-housed and exercising (wheel running) wild-type (WT) and SERT heterozygous (HET) mice. We also assessed hippocampal-dependent cognition using the Morris water maze (MWM) and a spatial pattern separation touchscreen task. KEY RESULTS SERT HET mice had impaired hippocampal LTP regardless of the housing conditions. Exercise increased hippocampal neurogenesis in WT mice. However, this was not observed in SERT HET animals, even though both genotypes used the running wheels to a similar extent. We also found that standard-housed SERT HET mice displayed altered cognitive flexibility than WT littermate controls in the MWM reversal learning task. However, SERT HET mice no longer exhibited this phenotype after exercise. Cognitive changes, specific to SERT HET mice in the exercise condition, were also revealed on the touchscreen spatial pattern separation task, especially when the cognitive pattern separation load was at its highest. CONCLUSIONS AND IMPLICATIONS Our study is the first evidence of reduced hippocampal LTP in SERT HET mice. We also show that functional SERT is required for exercise-induced increase in adult neurogenesis. Paradoxically, exercise had a negative impact on hippocampal-dependent cognitive tasks, especially in SERT HET mice. Taken together, our results suggest unique complex interactions between exercise and altered 5-HT homeostasis.
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Affiliation(s)
- Jake Rogers
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Feng Chen
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Davor Stanic
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Farheen Farzana
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Shanshan Li
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Ariel M Zeleznikow-Johnston
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Jess Nithianantharajah
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Leonid Churilov
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia.,School of Mathematical and Geospatial Sciences, RMIT University, Melbourne, VIC, Australia
| | - Paul A Adlard
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Laurence Lanfumey
- UMR S894, Université Paris Descartes, Paris, France.,Centre de Psychiatrie et Neurosciences, Inserm UMR 894, Paris, France
| | - Anthony J Hannan
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia.,Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, VIC, Australia.,Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, VIC, Australia
| | - Thibault Renoir
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia.,Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, VIC, Australia
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27
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Anxiety-like features and spatial memory problems as a consequence of hippocampal SV2A expression. PLoS One 2019; 14:e0217882. [PMID: 31166988 PMCID: PMC6550411 DOI: 10.1371/journal.pone.0217882] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 05/20/2019] [Indexed: 02/08/2023] Open
Abstract
The Synaptic Vesicle Protein 2A (SV2A) is a transmembrane protein whose presence is reduced both in animal models and in patients with chronic epilepsy. Besides its implication in the epileptic process, the behavioural consequences of the changes in its expression remain unclear. The purpose of our research is to better understand the possible role(s) of this protein through the phenotype of cKO (Grik4 Cre+/-, SV2A lox/lox) mice, male and female, which present a specific decrease of SV2A expression levels in the hippocampal glutamatergic neurons but without any epileptic seizures. In this study, we compare the cKO mice with cHZ (Grik4 Cre+/-, SV2A lox/+) and WT (Grik4 Cre+/+, SV2A lox/lox) mice through a battery of tests, used to evaluate different features: the anxiety-related features (Elevated Plus Maze), the locomotor activity (Activity Chambers), the contextual fear-related memory (Contextual Fear Conditioning), and the spatial memory (Barnes Maze). Our results showed statistically significant differences in the habituation to a new environment, an increase in the anxiety levels and spatial memory deficit in the cHZ and cKO groups, compared to the WT group. No statistically significant differences due to the genotype appeared in the spontaneous locomotor activity or the fear-linked memory. However, sexual differences were observed in this last feature. These results highlight not only an important role of the SV2A protein in the cognitive and anxiety problems typically encountered in epileptic patients, but also a possible role in the symptomatology of other neurodegenerative diseases, such as the Alzheimer’s disease.
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28
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Hippocampal NPY Y2 receptors modulate memory depending on emotional valence and time. Neuropharmacology 2018; 143:20-28. [DOI: 10.1016/j.neuropharm.2018.09.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 08/29/2018] [Accepted: 09/11/2018] [Indexed: 12/13/2022]
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29
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Hansen SN, Schou-Pedersen AMV, Lykkesfeldt J, Tveden-Nyborg P. Spatial Memory Dysfunction Induced by Vitamin C Deficiency Is Associated with Changes in Monoaminergic Neurotransmitters and Aberrant Synapse Formation. Antioxidants (Basel) 2018; 7:antiox7070082. [PMID: 29966224 PMCID: PMC6070945 DOI: 10.3390/antiox7070082] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 06/21/2018] [Accepted: 06/27/2018] [Indexed: 01/11/2023] Open
Abstract
Vitamin C (vitC) is important in the developing brain, acting both as an essential antioxidant and as co-factor in the synthesis and metabolism of monoaminergic neurotransmitters. In guinea pigs, vitC deficiency results in increased oxidative stress, reduced hippocampal volume and neuronal numbers, and deficits in spatial memory. This study investigated the effects of 8 weeks of either sufficient (923 mg vitC/kg feed) or deficient (100 mg vitC/kg feed) levels of dietary vitC on hippocampal monoaminergic neurotransmitters and markers of synapse formation in young guinea pigs with spatial memory deficits. Western blotting and high performance liquid chromatography (HPLC) were used to quantify the selected markers. VitC deficiency resulted in significantly reduced protein levels of synaptophysin (p = 0.016) and a decrease in 5-hydroxyindoleacetic acid/5-hydroxytryptamine ratio (p = 0.0093). Protein expression of the N-methyl-d-aspartate receptor subunit 1 and monoamine oxidase A were reduced, albeit not reaching statistical significance (p = 0.0898 and p = 0.067, respectively). Our findings suggest that vitC deficiency induced spatial memory deficits might be mediated by impairments in neurotransmission and synaptic development.
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Affiliation(s)
- Stine Normann Hansen
- Section for Experimental Animal Models, Department of Veterinary and Animal Sciences, University of Copenhagen, Thorvaldensvej 57, Ground Floor, 1870 Frederiksberg C, Denmark.
| | - Anne Marie V Schou-Pedersen
- Section for Experimental Animal Models, Department of Veterinary and Animal Sciences, University of Copenhagen, Thorvaldensvej 57, Ground Floor, 1870 Frederiksberg C, Denmark.
| | - Jens Lykkesfeldt
- Section for Experimental Animal Models, Department of Veterinary and Animal Sciences, University of Copenhagen, Thorvaldensvej 57, Ground Floor, 1870 Frederiksberg C, Denmark.
| | - Pernille Tveden-Nyborg
- Section for Experimental Animal Models, Department of Veterinary and Animal Sciences, University of Copenhagen, Thorvaldensvej 57, Ground Floor, 1870 Frederiksberg C, Denmark.
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30
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Gallo FT, Katche C, Morici JF, Medina JH, Weisstaub NV. Immediate Early Genes, Memory and Psychiatric Disorders: Focus on c-Fos, Egr1 and Arc. Front Behav Neurosci 2018; 12:79. [PMID: 29755331 PMCID: PMC5932360 DOI: 10.3389/fnbeh.2018.00079] [Citation(s) in RCA: 214] [Impact Index Per Article: 35.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 04/10/2018] [Indexed: 01/08/2023] Open
Abstract
Many psychiatric disorders, despite their specific characteristics, share deficits in the cognitive domain including executive functions, emotional control and memory. However, memory deficits have been in many cases undervalued compared with other characteristics. The expression of Immediate Early Genes (IEGs) such as, c-fos, Egr1 and arc are selectively and promptly upregulated in learning and memory among neuronal subpopulations in regions associated with these processes. Changes in expression in these genes have been observed in recognition, working and fear related memories across the brain. Despite the enormous amount of data supporting changes in their expression during learning and memory and the importance of those cognitive processes in psychiatric conditions, there are very few studies analyzing the direct implication of the IEGs in mental illnesses. In this review, we discuss the role of some of the most relevant IEGs in relation with memory processes affected in psychiatric conditions.
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Affiliation(s)
- Francisco T Gallo
- Instituto de Fisiología y Biofísica Bernardo Houssay, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
| | - Cynthia Katche
- Instituto de Biología Celular y Neurociencias (IBCN) Dr. Eduardo de Robertis, Facultad de Medicina, CONICET, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
| | - Juan F Morici
- Instituto de Fisiología y Biofísica Bernardo Houssay, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
| | - Jorge H Medina
- Instituto de Biología Celular y Neurociencias (IBCN) Dr. Eduardo de Robertis, Facultad de Medicina, CONICET, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina.,Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos (UBA), Buenos Aires, Argentina
| | - Noelia V Weisstaub
- Instituto de Fisiología y Biofísica Bernardo Houssay, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
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31
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Soualeh N, Soulimani R, Bouayed J. Hippocampal-dependent memory deficit induced by perinatal exposure to polutted eels in middle-aged offspring mice: Sex differential effects. Toxicol Lett 2017; 280:247-258. [PMID: 28847518 DOI: 10.1016/j.toxlet.2017.08.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 08/20/2017] [Accepted: 08/21/2017] [Indexed: 01/11/2023]
Abstract
The effects of perinatal exposure to low, intermediate, or highly polluted eels on neonatal, postnatal, adult and middle-aged brain inflammation, and on cognitive performances of middle-aged offspring mice were compared to those of offspring controls. Inflammatory markers in microglia were assessed in offspring on the postnatal days-PNDs 1, 21, 100 and 330. Activated p38MAPK, ERK-1/2 and p65, and acetylcholine levels were assessed in the middle-aged hippocampus. Plasma myeloperoxidase and corticosterone levels were evaluated at PND 330. Learning and its retention, and working memory in middle-aged offspring were assessed using the Morris water maze, and Y-maze. Our results showed enhanced microglia production of inflammatory markers across the lifespan of male as well as female exposed offspring. Inflammation and increased p38 MAPK activation were detected in the exposed middle-aged hippocampus of both exposed sexes. Significant levels of MPO, but not corticosterone, were found in middle-aged males and females perinatally exposed to eels. However, decreases in ERK1/2 and p65 activation, and acetylcholine levels were only detected in female hippocampus exposed to either intermediately or highly polluted eels. Sex selective effects were also detected with regard to memory, the only altered cognitive function. Thus, middle-aged females, but not males, perinatally exposed to either intermediately or highly polluted eels take longer to locate the escape platform, spend considerably less time in the platform and perform less visit to the platform in the retention test. Our results suggest perinatal programming of hippocampal-dependent memory deficit by inflammation in middle-aged offspring, in sex and dose dependent manner.
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Affiliation(s)
- Nidhal Soualeh
- Université de Lorraine, Neurotoxicologie Alimentaire et Bioactivité, Rue du Général Delestraint, Campus Bridoux, 57070 Metz, France
| | - Rachid Soulimani
- Université de Lorraine, Neurotoxicologie Alimentaire et Bioactivité, Rue du Général Delestraint, Campus Bridoux, 57070 Metz, France
| | - Jaouad Bouayed
- Université de Lorraine, Neurotoxicologie Alimentaire et Bioactivité, Rue du Général Delestraint, Campus Bridoux, 57070 Metz, France.
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32
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Song NN, Huang Y, Yu X, Lang B, Ding YQ, Zhang L. Divergent Roles of Central Serotonin in Adult Hippocampal Neurogenesis. Front Cell Neurosci 2017; 11:185. [PMID: 28713247 PMCID: PMC5492328 DOI: 10.3389/fncel.2017.00185] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 06/16/2017] [Indexed: 11/13/2022] Open
Abstract
The central serotonin (5-HT) system is the main target of selective serotonin reuptake inhibitors (SSRIs), the first-line antidepressants widely used in current general practice. One of the prominent features of chronic SSRI treatment in rodents is the enhanced adult neurogenesis in the hippocampus, which has been proposed to contribute to antidepressant effects. Therefore, tremendous effort has been made to decipher how central 5-HT regulates adult hippocampal neurogenesis. In this paper, we review how changes in the central serotonergic system alter adult hippocampal neurogenesis. We focus on data obtained from three categories of genetically engineered mouse models: (1) mice with altered central 5-HT levels from embryonic stages, (2) mice with deletion of 5-HT receptors from embryonic stages, and (3) mice with altered central 5-HT system exclusively in adulthood. These recent findings provide unique insights to interpret the multifaceted roles of central 5-HT on adult hippocampal neurogenesis and its associated effects on depression.
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Affiliation(s)
- Ning-Ning Song
- Key Laboratory of Arrhythmias, Ministry of Education, East Hospital, Tongji University School of MedicineShanghai, China.,Department of Anatomy and Neurobiology, Tongji University School of MedicineShanghai, China
| | - Ying Huang
- Key Laboratory of Arrhythmias, Ministry of Education, East Hospital, Tongji University School of MedicineShanghai, China.,Department of Anatomy and Neurobiology, Tongji University School of MedicineShanghai, China
| | - Xin Yu
- Key Laboratory of Arrhythmias, Ministry of Education, East Hospital, Tongji University School of MedicineShanghai, China.,Department of Anatomy and Neurobiology, Tongji University School of MedicineShanghai, China
| | - Bing Lang
- Key Laboratory of Arrhythmias, Ministry of Education, East Hospital, Tongji University School of MedicineShanghai, China.,Department of Anatomy and Neurobiology, Tongji University School of MedicineShanghai, China.,Mental Health Institute of the Second Xiangya Hospital, National Clinical Research Center on Mental Disorders, National Technology Institute on Mental Disorders, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South UniversityChangsha, China
| | - Yu-Qiang Ding
- Key Laboratory of Arrhythmias, Ministry of Education, East Hospital, Tongji University School of MedicineShanghai, China.,Department of Anatomy and Neurobiology, Tongji University School of MedicineShanghai, China
| | - Lei Zhang
- Key Laboratory of Arrhythmias, Ministry of Education, East Hospital, Tongji University School of MedicineShanghai, China.,Department of Anatomy and Neurobiology, Tongji University School of MedicineShanghai, China
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33
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Kraus C, Castrén E, Kasper S, Lanzenberger R. Serotonin and neuroplasticity - Links between molecular, functional and structural pathophysiology in depression. Neurosci Biobehav Rev 2017; 77:317-326. [PMID: 28342763 DOI: 10.1016/j.neubiorev.2017.03.007] [Citation(s) in RCA: 254] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 02/23/2017] [Accepted: 03/12/2017] [Indexed: 12/26/2022]
Abstract
Serotonin modulates neuroplasticity, especially during early life, and dysfunctions in both systems likewise contribute to pathophysiology of depression. Recent findings demonstrate that serotonin reuptake inhibitors trigger reactivation of juvenile-like neuroplasticity. How these findings translate to clinical antidepressant treatment in major depressive disorder remains unclear. With this review, we link preclinical with clinical work on serotonin and neuroplasticity to bring two pathophysiologic models in clinical depression closer together. Dysfunctional developmental plasticity impacts on later-life cognitive and emotional functions, changes of synaptic serotonin levels and receptor levels are coupled with altered synaptic plasticity and neurogenesis. Structural magnetic resonance imaging in patients reveals disease-state-specific reductions of gray matter, a marker of neuroplasticity, and reversibility upon selective serotonin reuptake inhibitor treatment. Translational evidence from magnetic resonance imaging in animals support that reduced densities and sizes of neurons and reduced hippocampal volumes in depressive patients could be attributable to changes of serotonergic neuroplasticity. Since ketamine, physical exercise or learning enhance neuroplasticity, combinatory paradigms with selective serotonin reuptake inhibitors could enhance clinical treatment of depression.
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Affiliation(s)
- Christoph Kraus
- NEUROIMAGING LABs (NIL) - PET & MRI & EEG & Chemical Lab Department of Psychiatry and Psychotherapy Medical University of Vienna
| | - Eero Castrén
- Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Siegfried Kasper
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria(1)
| | - Rupert Lanzenberger
- NEUROIMAGING LABs (NIL) - PET & MRI & EEG & Chemical Lab Department of Psychiatry and Psychotherapy Medical University of Vienna.
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Abstract
The hippocampus plays an important role in emotional and cognitive processing, and both of these domains are affected in patients with major depressive disorder (MDD). Extensive preclinical research and the notion that modulation of serotonin (5-HT) neurotransmission plays a key role in the therapeutic efficacy of selective serotonin reuptake inhibitors (SSRIs) support the view that 5-HT is important for hippocampal function in normal and disease-like conditions. The hippocampus is densely innervated by serotonergic fibers, and the majority of 5-HT receptor subtypes are expressed there. Furthermore, hippocampal cells often co-express multiple 5-HT receptor subtypes that can have either complementary or opposing effects on cell function, adding to the complexity of 5-HT neurotransmission. Here we review the current knowledge of how 5-HT, through its various receptor subtypes, modulates hippocampal output and the activity of hippocampal pyramidal cells in rodents. In addition, we discuss the relevance of 5-HT modulation for cognitive processing in rodents and possible clinical implications of these results in patients with MDD. Finally, we review the data on how SSRIs and vortioxetine, an antidepressant with multimodal activity, affect hippocampal function, including cognitive processing, from both a preclinical and clinical perspective.
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35
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Lerch S, Dormann C, Brandwein C, Gass P, Chourbaji S. The scent of stress: environmental challenge in the peripartum environment of mice affects emotional behaviours of the adult offspring in a sex-specific manner. Lab Anim 2015; 50:167-78. [PMID: 26408077 DOI: 10.1177/0023677215603260] [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] [Indexed: 12/20/2022]
Abstract
Early adverse experiences are known to influence the risk of developing psychiatric disorders later. To shed further light on the development of laboratory mice, we systematically examined the influence of a prenatal or postnatal olfactory stressor, namely unfamiliar male mouse faeces, presented to pregnant or nursing mouse dams. Maternal and offspring behaviours were then examined. Maternal behaviours relative to controls revealed changes in nest building by the pregnant dams exposed to the unfamiliar faeces. There were no differences among groups on pup retrieval or exploration by the dams. Behavioural phenotyping of male and female offspring as adults included measures of exploration, anxiety, social and depressive-like behaviours. Additionally, serum corticosterone was assessed as a marker of physiological stress response. Group differences were dependent on the sex of the adult offspring. Males raised by dams that were stressed during pregnancy presented elevated emotionality as indicated by increased numbers of faecal boluses in the open field paradigm. Consistent with the effects of prenatal stress on the males only the prenatally stressed females had higher body weights than their respective controls. Indeed, males in both experimental groups had higher circulating corticosterone levels. By contrast, female offspring of dams exposed to the olfactory stressor after parturition were more anxious in the O-maze as indicated by increased latencies in entering the exposed areas of the maze. These findings emphasize the necessity for researchers to consider the pre- and postnatal environments, even of mice with almost identical genetic backgrounds, in designing experiments and interpreting their data.
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Affiliation(s)
- S Lerch
- Interfaculty Biomedical Research Facility (IBF), University of Heidelberg, Central Institute of Mental Health (ZI) Mannheim, University of Heidelberg, Germany
| | - C Dormann
- Interfaculty Biomedical Research Facility (IBF), University of Heidelberg, Central Institute of Mental Health (ZI) Mannheim, University of Heidelberg, Germany
| | - C Brandwein
- Interfaculty Biomedical Research Facility (IBF), University of Heidelberg, Central Institute of Mental Health (ZI) Mannheim, University of Heidelberg, Germany
| | - P Gass
- Interfaculty Biomedical Research Facility (IBF), University of Heidelberg, Central Institute of Mental Health (ZI) Mannheim, University of Heidelberg, Germany
| | - S Chourbaji
- Interfaculty Biomedical Research Facility (IBF), University of Heidelberg, Central Institute of Mental Health (ZI) Mannheim, University of Heidelberg, Germany
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36
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Szentágotai-Tătar A, Chiș A, Vulturar R, Dobrean A, Cândea DM, Miu AC. Shame and Guilt-Proneness in Adolescents: Gene-Environment Interactions. PLoS One 2015; 10:e0134716. [PMID: 26230319 PMCID: PMC4521752 DOI: 10.1371/journal.pone.0134716] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 07/02/2015] [Indexed: 12/16/2022] Open
Abstract
Rooted in people’s preoccupation with how they are perceived and evaluated, shame and guilt are self-conscious emotions that play adaptive roles in social behavior, but can also contribute to psychopathology when dysregulated. Shame and guilt-proneness develop during childhood and adolescence, and are influenced by genetic and environmental factors that are little known to date. This study investigated the effects of early traumatic events and functional polymorphisms in the brain-derived neurotrophic factor (BDNF) gene and the serotonin transporter gene promoter (5-HTTLPR) on shame and guilt in adolescents. A sample of N = 271 healthy adolescents between 14 and 17 years of age filled in measures of early traumatic events and proneness to shame and guilt, and were genotyped for the BDNF Val66Met and 5-HTTLPR polymorphisms. Results of moderator analyses indicated that trauma intensity was positively associated with guilt-proneness only in carriers of the low-expressing Met allele of BDNF Val66Met. This is the first study that identifies a gene-environment interaction that significantly contributes to guilt proneness in adolescents, with potential implications for developmental psychopathology.
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Affiliation(s)
- Aurora Szentágotai-Tătar
- Department of Clinical Psychology and Psychotherapy, Babeș-Bolyai University, Cluj-Napoca, Cluj, Romania
- * E-mail:
| | - Adina Chiș
- Department of Cell and Molecular Biology, Iuliu Hațieganu University of Medicine and Pharmacy, Cluj, Cluj-Napoca, Romania
| | - Romana Vulturar
- Department of Cell and Molecular Biology, Iuliu Hațieganu University of Medicine and Pharmacy, Cluj, Cluj-Napoca, Romania
| | - Anca Dobrean
- Department of Clinical Psychology and Psychotherapy, Babeș-Bolyai University, Cluj-Napoca, Cluj, Romania
| | - Diana Mirela Cândea
- Department of Clinical Psychology and Psychotherapy, Babeș-Bolyai University, Cluj-Napoca, Cluj, Romania
| | - Andrei C. Miu
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, Cluj-Napoca, Cluj, Romania
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Kloke V, Schreiber RS, Bodden C, Möllers J, Ruhmann H, Kaiser S, Lesch KP, Sachser N, Lewejohann L. Hope for the best or prepare for the worst? Towards a spatial cognitive bias test for mice. PLoS One 2014; 9:e105431. [PMID: 25137069 PMCID: PMC4138164 DOI: 10.1371/journal.pone.0105431] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 07/21/2014] [Indexed: 01/08/2023] Open
Abstract
Cognitive bias, the altered information processing resulting from the background emotional state of an individual, has been suggested as a promising new indicator of animal emotion. Comparable to anxious or depressed humans, animals in a putatively negative emotional state are more likely to judge an ambiguous stimulus as if it predicts a negative event, than those in positive states. The present study aimed to establish a cognitive bias test for mice based on a spatial judgment task and to apply it in a pilot study to serotonin transporter (5-HTT) knockout mice, a well-established mouse model for the study of anxiety- and depression-related behavior. In a first step, we validated that our setup can assess different expectations about the outcome of an ambiguous stimulus: mice having learned to expect something positive within a maze differed significantly in their behavior towards an unfamiliar location than animals having learned to expect something negative. In a second step, the use of spatial location as a discriminatory stimulus was confirmed by showing that mice interpret an ambiguous stimulus depending on its spatial location, with a position exactly midway between a positive and a negative reference point provoking the highest level of ambiguity. Finally, the anxiety- and depression-like phenotype of the 5-HTT knockout mouse model manifested--comparable to human conditions--in a trend for a negatively distorted interpretation of ambiguous information, albeit this effect was not statistically significant. The results suggest that the present cognitive bias test provides a useful basis to study the emotional state in mice, which may not only increase the translational value of animal models in the study of human affective disorders, but which is also a central objective of animal welfare research.
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Affiliation(s)
- Vanessa Kloke
- Department of Behavioural Biology, University of Münster, Münster, Germany
- Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, Münster, Germany
| | - Rebecca S. Schreiber
- Department of Behavioural Biology, University of Münster, Münster, Germany
- Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, Münster, Germany
| | - Carina Bodden
- Department of Behavioural Biology, University of Münster, Münster, Germany
| | - Julian Möllers
- Department of Behavioural Biology, University of Münster, Münster, Germany
| | - Hanna Ruhmann
- Department of Behavioural Biology, University of Münster, Münster, Germany
| | - Sylvia Kaiser
- Department of Behavioural Biology, University of Münster, Münster, Germany
- Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, Münster, Germany
| | - Klaus-Peter Lesch
- Division of Molecular Psychiatry, Laboratory of Translational Neuroscience, Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, Würzburg, Germany
| | - Norbert Sachser
- Department of Behavioural Biology, University of Münster, Münster, Germany
- Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, Münster, Germany
| | - Lars Lewejohann
- Department of Behavioural Biology, University of Münster, Münster, Germany
- Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, Münster, Germany
- Behavioral Biology, University of Osnabrück, Osnabrück, Germany
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38
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The role of serotonin in adult hippocampal neurogenesis. Behav Brain Res 2014; 277:49-57. [PMID: 25125239 DOI: 10.1016/j.bbr.2014.07.038] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 07/22/2014] [Accepted: 07/23/2014] [Indexed: 12/17/2022]
Abstract
Serotonin is probably best known for its role in conveying a sense of contentedness and happiness. It is one of the most unique and pharmacologically complex monoamines in both the peripheral and central nervous system (CNS). Serotonin has become in focus of interest for the treatment of depression with multiple serotonin-mimetic and modulators of adult neurogenesis used clinically. Here we will take a broad view of serotonin from development to its physiological role as a neurotransmitter and its contribution to homeostasis of the adult rodent hippocampus. This chapter reflects the most significant findings on cellular and molecular mechanisms from neuroscientists in the field over the last two decades. We illustrate the action of serotonin by highlighting basic receptor targeting studies, and how receptors impact brain function. We give an overview of recent genetically modified mouse models that differ in serotonin availability and focus on the role of the monoamine in antidepressant response. We conclude with a synthesis of the most recent data surrounding the role of serotonin in activity and hippocampal neurogenesis. This synopsis sheds light on the mechanisms and potential therapeutic model by which serotonin plays a critical role in the maintenance of mood.
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