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Carleial S, Nätt D, Unternährer E, Elbert T, Robjant K, Wilker S, Vukojevic V, Kolassa IT, Zeller AC, Koebach A. DNA methylation changes following narrative exposure therapy in a randomized controlled trial with female former child soldiers. Sci Rep 2021; 11:18493. [PMID: 34531495 PMCID: PMC8445994 DOI: 10.1038/s41598-021-98067-9] [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] [Received: 01/07/2021] [Accepted: 09/02/2021] [Indexed: 02/08/2023] Open
Abstract
The aftermath of traumatization lives on in the neural and epigenetic traces creating a momentum of affliction in the psychological and social realm. Can psychotherapy reorganise these memories through changes in DNA methylation signatures? Using a randomised controlled parallel group design, we examined methylome-wide changes in saliva samples of 84 female former child soldiers from Eastern DR Congo before and six months after Narrative Exposure Therapy. Treatment predicted differentially methylated positions (DMPs) related to ALCAM, RIPOR2, AFAP1 and MOCOS. In addition, treatment associations overlapped at gene level with baseline clinical and social outcomes. Treatment related DMPs are involved in memory formation-the key agent in trauma focused treatments-and enriched for molecular pathways commonly affected by trauma related disorders. Results were partially replicated in an independent sample of 53 female former child soldiers from Northern Uganda. Our results suggest a molecular impact of psychological treatment in women with war-related childhood trauma.Trial registration: Addressing Heightened Levels of Aggression in Traumatized Offenders With Psychotherapeutic Means (ClinicalTrials.gov Identifier: NCT02992561, 14/12/2016).
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Affiliation(s)
- Samuel Carleial
- grid.9811.10000 0001 0658 7699Department of Psychology, Centre for Psychiatry, University of Konstanz, Feuerstein-Strasse. 55, Haus 22, 78479 Konstanz, Germany
| | - Daniel Nätt
- grid.5640.70000 0001 2162 9922Division of Neurobiology, Department of Biomedical and Clinical Sciences, University of Linköping, Building 463, Room 12.023, Linköping, Sweden
| | - Eva Unternährer
- grid.9811.10000 0001 0658 7699Department of Psychology, Centre for Psychiatry, University of Konstanz, Feuerstein-Strasse. 55, Haus 22, 78479 Konstanz, Germany ,grid.6612.30000 0004 1937 0642Child- and Adolescent Research Department, Psychiatric University Hospitals Basel (UPK), University of Basel, Basel, Switzerland
| | - Thomas Elbert
- grid.9811.10000 0001 0658 7699Department of Psychology, Centre for Psychiatry, University of Konstanz, Feuerstein-Strasse. 55, Haus 22, 78479 Konstanz, Germany ,Vivo International E.V., Postbox 5108, 78430 Konstanz, Germany
| | - Katy Robjant
- Vivo International E.V., Postbox 5108, 78430 Konstanz, Germany
| | - Sarah Wilker
- Vivo International E.V., Postbox 5108, 78430 Konstanz, Germany ,grid.7491.b0000 0001 0944 9128Department of Psychology and Sports Science, University of Bielefeld, 33501 Bielefeld, Germany
| | - Vanja Vukojevic
- grid.6612.30000 0004 1937 0642Psychiatric University Clinics, Transfaculty Research Platform, University of Basel, Wilhelm Klein-Strasse 27, CH-4012 Basel, Switzerland
| | - Iris-Tatjana Kolassa
- Vivo International E.V., Postbox 5108, 78430 Konstanz, Germany ,grid.6582.90000 0004 1936 9748Department of Clinical and Biological Psychology, Institute of Psychology & Education, University of Ulm, Ulm University, Ulm, Germany
| | - Anja C. Zeller
- grid.9811.10000 0001 0658 7699Department of Psychology, Centre for Psychiatry, University of Konstanz, Feuerstein-Strasse. 55, Haus 22, 78479 Konstanz, Germany ,Vivo International E.V., Postbox 5108, 78430 Konstanz, Germany
| | - Anke Koebach
- grid.9811.10000 0001 0658 7699Department of Psychology, Centre for Psychiatry, University of Konstanz, Feuerstein-Strasse. 55, Haus 22, 78479 Konstanz, Germany ,Vivo International E.V., Postbox 5108, 78430 Konstanz, Germany
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2
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Pandey K, Sharma SK. Activity- and memory training-induced acetylation of α-tubulin in the hippocampus. Neurobiol Learn Mem 2020; 171:107226. [PMID: 32247664 DOI: 10.1016/j.nlm.2020.107226] [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: 10/24/2019] [Revised: 03/05/2020] [Accepted: 03/29/2020] [Indexed: 11/19/2022]
Abstract
Posttranslational modifications play crucial roles in synaptic plasticity and memory formation. The important role of histone acetylation is well established in these processes. However, activity-dependent regulation of acetylation of non-histone proteins is not well understood. We previously showed that α-tubulin is acetylated in an activity-dependent manner. Here, we show that cyclin-dependent kinase 5 (CDK5) plays an important role in α-tubulin acetylation induced by KCl depolarization or N-methyl-D-aspartate stimulation of the hippocampal slices. In addition, KCl depolarization inhibits the activity of SIRT2, an α-tubulin deacetylase. The inhibitory effect of KCl on SIRT2 activity requires CDK5 activity. Furthermore, α-tubulin acetylation is enhanced by memory training in object recognition task. These results suggest that memory formation may involve α-tubulin acetylation.
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Affiliation(s)
- Kiran Pandey
- National Brain Research Centre, Manesar 122052, Haryana, India
| | - Shiv K Sharma
- National Brain Research Centre, Manesar 122052, Haryana, India.
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3
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Williams AR, Kim ES, Lattal KM. Behavioral and immunohistochemical characterization of rapid reconditioning following extinction of contextual fear. Learn Mem 2019; 26:1-16. [PMID: 31527183 PMCID: PMC6749931 DOI: 10.1101/lm.048439.118] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 07/12/2019] [Indexed: 01/27/2023]
Abstract
A fundamental property of extinction is that the behavior that is suppressed during extinction can be unmasked through a number of postextinction procedures. Of the commonly studied unmasking procedures (spontaneous recovery, reinstatement, contextual renewal, and rapid reacquisition), rapid reacquisition is the only approach that allows a direct comparison between the impact of a conditioning trial before or after extinction. Thus, it provides an opportunity to evaluate the ways in which extinction changes a subsequent learning experience. In five experiments, we investigate the behavioral and neurobiological mechanisms of postextinction reconditioning. We show that rapid reconditioning of unsignaled contextual fear after extinction in male Long-Evans rats is associative and not affected by the number or duration of extinction sessions that we examined. We then evaluate c-Fos expression and histone acetylation (H4K8) in the hippocampus, amygdala, prefrontal cortex, and bed nucleus of the stria terminalis. We find that in general, initial conditioning has a stronger impact on c-Fos expression and acetylation than does reconditioning after extinction. We discuss implications of these results for theories of extinction and the neurobiology of conditioning and extinction.
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Affiliation(s)
- Amy R Williams
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - Earnest S Kim
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - K Matthew Lattal
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon 97239, USA
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4
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Giza JI, Kim J, Meyer HC, Anastasia A, Dincheva I, Zheng CI, Lopez K, Bains H, Yang J, Bracken C, Liston C, Jing D, Hempstead BL, Lee FS. The BDNF Val66Met Prodomain Disassembles Dendritic Spines Altering Fear Extinction Circuitry and Behavior. Neuron 2018; 99:163-178.e6. [PMID: 29909994 DOI: 10.1016/j.neuron.2018.05.024] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 01/18/2018] [Accepted: 05/15/2018] [Indexed: 11/16/2022]
Abstract
A human variant in the BDNF gene (Val66Met; rs6265) is associated with impaired fear extinction. Using super-resolution imaging, we demonstrate that the BDNF Met prodomain disassembles dendritic spines and eliminates synapses in hippocampal neurons. In vivo, ventral CA1 (vCA1) hippocampal neurons undergo similar morphological changes dependent on their transient co-expression of a SorCS2/p75NTR receptor complex during peri-adolescence. BDNF Met prodomain infusion into the vCA1 during this developmental time frame reduces dendritic spine density and prelimbic (PL) projections, impairing cued fear extinction. Adolescent BdnfMet/Met mice display similar spine and PL innervation deficits. Using fiber photometry, we found that, in wild-type mice, vCA1 neurons projecting to the PL encode extinction by enhancing neural activity in threat anticipation and rapidly subsiding their response. This adaptation is absent in BDNFMet/Met mice. We conclude that the BDNF Met prodomain renders vCA1-PL projection neurons underdeveloped, preventing their capacity for subsequent circuit modulation necessary for fear extinction. VIDEO ABSTRACT.
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Affiliation(s)
- Joanna I Giza
- Department of Psychiatry, Weill Cornell Medicine, New York, NY 10065, USA
| | - Jihye Kim
- Department of Psychiatry, Weill Cornell Medicine, New York, NY 10065, USA
| | - Heidi C Meyer
- Department of Psychiatry, Weill Cornell Medicine, New York, NY 10065, USA
| | - Agustin Anastasia
- Instituto de Investigación Médica Mercedes y Martín Ferreyra (INIMEC-CONICET-Universidad Nacional de Córdoba), Córdoba, Argentina
| | - Iva Dincheva
- Department of Psychiatry, Columbia University, New York, NY 10032, USA
| | - Crystal I Zheng
- Department of Psychiatry, Weill Cornell Medicine, New York, NY 10065, USA
| | - Katherine Lopez
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Henrietta Bains
- Department of Medicine, Weill Cornell Medicine, New York, NY 10065, USA
| | - Jianmin Yang
- Department of Medicine, Weill Cornell Medicine, New York, NY 10065, USA; Key Laboratory of Shaanxi Province Department for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, PR China
| | - Clay Bracken
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10065, USA
| | - Conor Liston
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Deqiang Jing
- Department of Psychiatry, Weill Cornell Medicine, New York, NY 10065, USA
| | | | - Francis S Lee
- Department of Psychiatry, Weill Cornell Medicine, New York, NY 10065, USA; Sackler Institute for Developmental Psychobiology, Weill Cornell Medicine, New York, NY 10065, USA.
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Iobbi C, Korte M, Zagrebelsky M. Nogo-66 Restricts Synaptic Strengthening via Lingo1 and the ROCK2-Cofilin Pathway to Control Actin Dynamics. Cereb Cortex 2018; 27:2779-2792. [PMID: 27166169 DOI: 10.1093/cercor/bhw122] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Nogo-A restricts long-term potentiation (LTP) at the Schaffer collateral-CA1 pathway in the adult hippocampus via 2 extracellular domains: Nogo-A-Δ20 and Nogo-66. Nogo-66 signals via Nogo Receptor 1 (NgR1) to regulate synaptic function. Whether the NgR1 coreceptors Lingo1 and p75NTR are involved in the signaling in this context is still not known. Moreover, the intracellular cascade mediating the activity of Nogo-66 in restricting LTP is unexplored. We combine electrophysiology and biochemistry in acute hippocampal slices and demonstrate that a loss of function for Lingo1 results in a significant increase in LTP levels at the Schaffer collateral-CA1 pathway, and that Lingo1 is the NgR1 coreceptor mediating the role of Nogo-66 in restricting LTP. Our data show that p75NTR is not involved in mediating the Nogo-66 effect on LTP. Moreover, loss of function for p75NTR and NgR1 equally attenuate LTD, suggesting that p75NTR might mediate the NgR1-dependent regulation of LTD, independently of Nogo-66. Finally, our results indicate that Nogo-66 signaling limits LTP via the ROCK2-Cofilin pathway to control the dynamics of the actin cytoskeleton. The present results elucidate the signaling pathway activated by Nogo-66 to control LTP and contribute to the understanding of how Nogo-A stabilizes the neural circuits to limit activity-dependent plasticity events in the mature hippocampus.
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Affiliation(s)
- Cristina Iobbi
- Zoological Institute, Division of Cellular Neurobiology, TU Braunschweig, 38106, Braunschweig, Germany
| | - Martin Korte
- Zoological Institute, Division of Cellular Neurobiology, TU Braunschweig, 38106, Braunschweig, Germany.,Helmholtz Centre for Infection Research, AG NIND, 38124, Braunschweig, Germany
| | - Marta Zagrebelsky
- Zoological Institute, Division of Cellular Neurobiology, TU Braunschweig, 38106, Braunschweig, Germany
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6
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Snow WM, Cadonic C, Cortes-Perez C, Roy Chowdhury SK, Djordjevic J, Thomson E, Bernstein MJ, Suh M, Fernyhough P, Albensi BC. Chronic dietary creatine enhances hippocampal-dependent spatial memory, bioenergetics, and levels of plasticity-related proteins associated with NF-κB. ACTA ACUST UNITED AC 2018; 25:54-66. [PMID: 29339557 PMCID: PMC5772392 DOI: 10.1101/lm.046284.117] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 11/03/2017] [Indexed: 12/23/2022]
Abstract
The brain has a high demand for energy, of which creatine (Cr) is an important regulator. Studies document neurocognitive benefits of oral Cr in mammals, yet little is known regarding their physiological basis. This study investigated the effects of Cr supplementation (3%, w/w) on hippocampal function in male C57BL/6 mice, including spatial learning and memory in the Morris water maze and oxygen consumption rates from isolated mitochondria in real time. Levels of transcription factors and related proteins (CREB, Egr1, and IκB to indicate NF-κB activity), proteins implicated in cognition (CaMKII, PSD-95, and Egr2), and mitochondrial proteins (electron transport chain Complex I, mitochondrial fission protein Drp1) were probed with Western blotting. Dietary Cr decreased escape latency/time to locate the platform (P < 0.05) and increased the time spent in the target quadrant (P < 0.01) in the Morris water maze. This was accompanied by increased coupled respiration (P < 0.05) in isolated hippocampal mitochondria. Protein levels of CaMKII, PSD-95, and Complex 1 were increased in Cr-fed mice, whereas IκB was decreased. These data demonstrate that dietary supplementation with Cr can improve learning, memory, and mitochondrial function and have important implications for the treatment of diseases affecting memory and energy homeostasis.
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Affiliation(s)
- Wanda M Snow
- Division of Neurodegenerative Disorders, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, Manitoba R2H 2A6, Canada
| | - Chris Cadonic
- Division of Neurodegenerative Disorders, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, Manitoba R2H 2A6, Canada
| | - Claudia Cortes-Perez
- Division of Neurodegenerative Disorders, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, Manitoba R2H 2A6, Canada
| | - Subir K Roy Chowdhury
- Division of Neurodegenerative Disorders, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, Manitoba R2H 2A6, Canada
| | - Jelena Djordjevic
- Division of Neurodegenerative Disorders, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, Manitoba R2H 2A6, Canada
| | - Ella Thomson
- Division of Neurodegenerative Disorders, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, Manitoba R2H 2A6, Canada
| | - Michael J Bernstein
- Department of Psychological and Social Sciences, Pennsylvania State University Abington, Abington, Pennsylvania 19001, USA
| | - Miyoung Suh
- Department of Human Nutritional Sciences, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Paul Fernyhough
- Division of Neurodegenerative Disorders, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, Manitoba R2H 2A6, Canada.,Department of Pharmacology & Therapeutics, University of Manitoba, Winnipeg, Manitoba R3E 0T6, Canada
| | - Benedict C Albensi
- Division of Neurodegenerative Disorders, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, Manitoba R2H 2A6, Canada.,Department of Pharmacology & Therapeutics, University of Manitoba, Winnipeg, Manitoba R3E 0T6, Canada
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7
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MicroRNA-mediated disruption of dendritogenesis during a critical period of development influences cognitive capacity later in life. Proc Natl Acad Sci U S A 2017; 114:9188-9193. [PMID: 28790189 DOI: 10.1073/pnas.1706069114] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The prenatal period of cortical development is important for the establishment of neural circuitry and functional connectivity of the brain; however, the molecular mechanisms underlying this process remain unclear. Here we report that disruption of the actin-cytoskeletal network in the developing mouse prefrontal cortex alters dendritic morphogenesis and synapse formation, leading to enhanced formation of fear-related memory in adulthood. These effects are mediated by a brain-enriched microRNA, miR-9, through its negative regulation of diaphanous homologous protein 1 (Diap1), a key organizer of the actin cytoskeletal assembly. Our findings not only revealed important regulation of dendritogenesis and synaptogenesis during early brain development but also demonstrated a tight link between these early developmental events and cognitive functions later in life.
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8
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Memory consolidation and expression of object recognition are susceptible to retroactive interference. Neurobiol Learn Mem 2017; 138:198-205. [DOI: 10.1016/j.nlm.2016.04.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 04/19/2016] [Accepted: 04/24/2016] [Indexed: 12/20/2022]
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9
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Lunardi P, Sachser RM, Sierra RO, Pedraza LK, Medina C, de la Fuente V, Romano A, Quillfeldt JA, de Oliveira Alvares L. Effects of Hippocampal LIMK Inhibition on Memory Acquisition, Consolidation, Retrieval, Reconsolidation, and Extinction. Mol Neurobiol 2017; 55:958-967. [DOI: 10.1007/s12035-016-0361-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 12/28/2016] [Indexed: 02/06/2023]
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10
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Lamprecht R. The Role of Actin Cytoskeleton in Memory Formation in Amygdala. Front Mol Neurosci 2016; 9:23. [PMID: 27065800 PMCID: PMC4815361 DOI: 10.3389/fnmol.2016.00023] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 03/21/2016] [Indexed: 11/13/2022] Open
Abstract
The central, lateral and basolateral amygdala (BLA) nuclei are essential for the formation of long-term memories including emotional and drug-related memories. Studying cellular and molecular mechanisms of memory in amygdala may lead to better understanding of how memory is formed and of fear and addiction-related disorders. A challenge is to identify molecules activated by learning that subserve cellular changes needed for memory formation and maintenance in amygdala. Recent studies show that activation of synaptic receptors during fear and drug-related learning leads to alteration in actin cytoskeleton dynamics and structure in amygdala. Such changes in actin cytoskeleton in amygdala are essential for fear and drug-related memories formation. Moreover, the actin cytoskeleton subserves, after learning, changes in neuronal morphogenesis and glutamate receptors trafficking in amygdala. These cellular events are involved in fear and drug-related memories formation. Actin polymerization is also needed for the maintenance of drug-associated memories in amygdala. Thus, the actin cytoskeleton is a key mediator between receptor activation during learning and cellular changes subserving long-term memory (LTM) in amygdala. The actin cytoskeleton may serve as a target for pharmacological treatment of fear memory associated with fear and anxiety disorders and drug addiction to prevent the debilitating consequences of these diseases.
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Snow WM, Pahlavan PS, Djordjevic J, McAllister D, Platt EE, Alashmali S, Bernstein MJ, Suh M, Albensi BC. Morris Water Maze Training in Mice Elevates Hippocampal Levels of Transcription Factors Nuclear Factor (Erythroid-derived 2)-like 2 and Nuclear Factor Kappa B p65. Front Mol Neurosci 2015; 8:70. [PMID: 26635523 PMCID: PMC4649017 DOI: 10.3389/fnmol.2015.00070] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 11/03/2015] [Indexed: 11/30/2022] Open
Abstract
Research has identified several transcription factors that regulate activity-dependent plasticity and memory, with cAMP-response element binding protein (CREB) being the most well-studied. In neurons, CREB activation is influenced by the transcription factor nuclear factor kappa B (NF-κB), considered central to immunity but more recently implicated in memory. The transcription factor early growth response-2 (Egr-2), an NF-κB gene target, is also associated with learning and memory. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2), an antioxidant transcription factor linked to NF-κB in pathological conditions, has not been studied in normal memory. Given that numerous transcription factors implicated in activity-dependent plasticity demonstrate connections to NF-κB, this study simultaneously evaluated protein levels of NF-κB, CREB, Egr-2, Nrf2, and actin in hippocampi from young (1 month-old) weanling CD1 mice after training in the Morris water maze, a hippocampal-dependent spatial memory task. After a 6-day acquisition period, time to locate the hidden platform decreased in the Morris water maze. Mice spent more time in the target vs. non-target quadrants of the maze, suggestive of recall of the platform location. Western blot data revealed a decrease in NF-κB p50 protein after training relative to controls, whereas NF-κB p65, Nrf2 and actin increased. Nrf2 levels were correlated with platform crosses in nearly all tested animals. These data demonstrate that training in a spatial memory task results in alterations in and associations with particular transcription factors in the hippocampus, including upregulation of NF-κB p65 and Nrf2. Training-induced increases in actin protein levels caution against its use as a loading control in immunoblot studies examining activity-dependent plasticity, learning, and memory.
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Affiliation(s)
- Wanda M Snow
- Division of Neurodegenerative Disorders, St. Boniface Hospital Research Winnipeg, MB, Canada ; Faculty of Health Sciences, Department of Pharmacology and Therapeutics, College of Medicine, University of Manitoba Winnipeg, MB, Canada
| | - Payam S Pahlavan
- Division of Neurodegenerative Disorders, St. Boniface Hospital Research Winnipeg, MB, Canada ; Faculty of Health Sciences, Department of Pharmacology and Therapeutics, College of Medicine, University of Manitoba Winnipeg, MB, Canada
| | - Jelena Djordjevic
- Division of Neurodegenerative Disorders, St. Boniface Hospital Research Winnipeg, MB, Canada ; Faculty of Health Sciences, Department of Pharmacology and Therapeutics, College of Medicine, University of Manitoba Winnipeg, MB, Canada
| | - Danielle McAllister
- Division of Neurodegenerative Disorders, St. Boniface Hospital Research Winnipeg, MB, Canada
| | - Eric E Platt
- Division of Neurodegenerative Disorders, St. Boniface Hospital Research Winnipeg, MB, Canada
| | - Shoug Alashmali
- Department of Human Nutritional Sciences, University of Manitoba Winnipeg, MB, Canada
| | - Michael J Bernstein
- Department of Psychological and Social Sciences, Pennsylvania State University Abington Abington, PA, USA
| | - Miyoung Suh
- Department of Human Nutritional Sciences, University of Manitoba Winnipeg, MB, Canada
| | - Benedict C Albensi
- Division of Neurodegenerative Disorders, St. Boniface Hospital Research Winnipeg, MB, Canada ; Faculty of Health Sciences, Department of Pharmacology and Therapeutics, College of Medicine, University of Manitoba Winnipeg, MB, Canada ; Faculty of Engineering, Department of Electrical and Computer Engineering, University of Manitoba Winnipeg, MB, Canada
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12
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Gao Q, Yao W, Wang J, Yang T, Liu C, Tao Y, Chen Y, Liu X, Ma L. Post-training activation of Rac1 in the basolateral amygdala is required for the formation of both short-term and long-term auditory fear memory. Front Mol Neurosci 2015; 8:65. [PMID: 26582975 PMCID: PMC4631819 DOI: 10.3389/fnmol.2015.00065] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 10/19/2015] [Indexed: 12/24/2022] Open
Abstract
Rac1, a member of the Rho family of small GTPases, is crucial for morphological changes of the mature neuronal synapse including spine formation and activity-dependent spine enlargement, while its role in the formation of associated memories, such as conditioned fear memory, is not clear. Here, we report that selective deletion of Rac1 in excitatory neurons, but not in parvalbumin inhibitory neurons, impaired short- and long-term memories (STM and LTM) of fear conditioning. Conditional knockout of Rac1 before associative fear training in the basolateral amygdala (BLA), a key area for fear memory acquisition and storage, impaired fear memory. The expression of dominant-negative mutant of Rac1, or infusion of Rac1 inhibitor NSC23766 into BLA blocked both STM and LTM of fear conditioning. Furthermore, selective inhibition of Rac1 activation in BLA immediately following fear conditioning impaired STM and LTM, demonstrating that fear conditioning-induced Rac1 activation in BLA plays a critical role in the formation of both STM and LTM of conditioned fear.
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Affiliation(s)
- Qinqin Gao
- State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University Shanghai, China
| | - Wenqing Yao
- State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University Shanghai, China
| | - Junjun Wang
- State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University Shanghai, China
| | - Tong Yang
- State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University Shanghai, China
| | - Cao Liu
- State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University Shanghai, China
| | - Yezheng Tao
- State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University Shanghai, China
| | - Yuejun Chen
- State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University Shanghai, China
| | - Xing Liu
- State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University Shanghai, China
| | - Lan Ma
- State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University Shanghai, China
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13
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Hitora-Imamura N, Miura Y, Teshirogi C, Ikegaya Y, Matsuki N, Nomura H. Prefrontal dopamine regulates fear reinstatement through the downregulation of extinction circuits. eLife 2015; 4. [PMID: 26226637 PMCID: PMC4547090 DOI: 10.7554/elife.08274] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 07/29/2015] [Indexed: 12/17/2022] Open
Abstract
Prevention of relapses is a major challenge in treating anxiety disorders. Fear reinstatement can cause relapse in spite of successful fear reduction through extinction-based exposure therapy. By utilising a contextual fear-conditioning task in mice, we found that reinstatement was accompanied by decreased c-Fos expression in the infralimbic cortex (IL) with reduction of synaptic input and enhanced c-Fos expression in the medial subdivision of the central nucleus of the amygdala (CeM). Moreover, we found that IL dopamine plays a key role in reinstatement. A reinstatement-inducing reminder shock induced c-Fos expression in the IL-projecting dopaminergic neurons in the ventral tegmental area, and the blocking of IL D1 signalling prevented reduction of synaptic input, CeM c-Fos expression, and fear reinstatement. These findings demonstrate that a dopamine-dependent inactivation of extinction circuits underlies fear reinstatement and may explain the comorbidity of substance use disorders and anxiety disorders.
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Affiliation(s)
- Natsuko Hitora-Imamura
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Yuki Miura
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Chie Teshirogi
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Yuji Ikegaya
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Norio Matsuki
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Hiroshi Nomura
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
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Baldi E, Bucherelli C. Brain sites involved in fear memory reconsolidation and extinction of rodents. Neurosci Biobehav Rev 2015; 53:160-90. [DOI: 10.1016/j.neubiorev.2015.04.003] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 03/30/2015] [Accepted: 04/06/2015] [Indexed: 12/21/2022]
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Peixoto LL, Wimmer ME, Poplawski SG, Tudor JC, Kenworthy CA, Liu S, Mizuno K, Garcia BA, Zhang NR, Giese K, Abel T. Memory acquisition and retrieval impact different epigenetic processes that regulate gene expression. BMC Genomics 2015; 16 Suppl 5:S5. [PMID: 26040834 PMCID: PMC4460846 DOI: 10.1186/1471-2164-16-s5-s5] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background A fundamental question in neuroscience is how memories are stored and retrieved in the brain. Long-term memory formation requires transcription, translation and epigenetic processes that control gene expression. Thus, characterizing genome-wide the transcriptional changes that occur after memory acquisition and retrieval is of broad interest and importance. Genome-wide technologies are commonly used to interrogate transcriptional changes in discovery-based approaches. Their ability to increase scientific insight beyond traditional candidate gene approaches, however, is usually hindered by batch effects and other sources of unwanted variation, which are particularly hard to control in the study of brain and behavior. Results We examined genome-wide gene expression after contextual conditioning in the mouse hippocampus, a brain region essential for learning and memory, at all the time-points in which inhibiting transcription has been shown to impair memory formation. We show that most of the variance in gene expression is not due to conditioning and that by removing unwanted variance through additional normalization we are able provide novel biological insights. In particular, we show that genes downregulated by memory acquisition and retrieval impact different functions: chromatin assembly and RNA processing, respectively. Levels of histone 2A variant H2AB are reduced only following acquisition, a finding we confirmed using quantitative proteomics. On the other hand, splicing factor Rbfox1 and NMDA receptor-dependent microRNA miR-219 are only downregulated after retrieval, accompanied by an increase in protein levels of miR-219 target CAMKIIγ. Conclusions We provide a thorough characterization of coding and non-coding gene expression during long-term memory formation. We demonstrate that unwanted variance dominates the signal in transcriptional studies of learning and memory and introduce the removal of unwanted variance through normalization as a necessary step for the analysis of genome-wide transcriptional studies in the context of brain and behavior. We show for the first time that histone variants are downregulated after memory acquisition, and splicing factors and microRNAs after memory retrieval. Our results provide mechanistic insights into the molecular basis of cognition by highlighting the differential involvement of epigenetic mechanisms, such as histone variants and post-transcriptional RNA regulation, after acquisition and retrieval of memory.
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Nachon O, Cleren C, Husson S, Huguet C, Auclair J, Faure S, Akirav I, Moreau JL, Garcia R. Prefrontal tetanic stimulation, following fear reconditioning, facilitates expression of previously acquired extinction. Neurobiol Learn Mem 2014; 113:62-8. [DOI: 10.1016/j.nlm.2013.12.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 11/10/2013] [Accepted: 12/05/2013] [Indexed: 01/09/2023]
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EphrinA4 mimetic peptide targeted to EphA binding site impairs the formation of long-term fear memory in lateral amygdala. Transl Psychiatry 2014; 4:e450. [PMID: 25268254 PMCID: PMC4203006 DOI: 10.1038/tp.2014.76] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2013] [Revised: 06/26/2014] [Accepted: 07/22/2014] [Indexed: 01/26/2023] Open
Abstract
Fear conditioning leads to long-term fear memory formation and is a model for studying fear-related psychopathologies conditions such as phobias and posttraumatic stress disorder. Long-term fear memory formation is believed to involve alterations of synaptic efficacy mediated by changes in synaptic transmission and morphology in lateral amygdala (LA). EphrinA4 and its cognate Eph receptors are intimately involved in regulating neuronal morphogenesis, synaptic transmission and plasticity. To assess possible roles of ephrinA4 in fear memory formation we designed and used a specific inhibitory ephrinA4 mimetic peptide (pep-ephrinA4) targeted to EphA binding site. We show that this peptide, composed of the ephrinA4 binding domain, interacts with EphA4 and inhibits ephrinA4-induced phosphorylation of EphA4. Microinjection of the pep-ephrinA4 into rat LA 30 min before training impaired long- but not short-term fear conditioning memory. Microinjection of a control peptide derived from a nonbinding E helix site of ephrinA4, that does not interact with EphA, had no effect on fear memory formation. Microinjection of pep-ephrinA4 into areas adjacent to the amygdala had no effect on fear memory. Acute systemic administration of pep-ephrinA4 1 h after training also impaired long-term fear conditioning memory formation. These results demonstrate that ephrinA4 binding sites in LA are essential for long-term fear memory formation. Moreover, our research shows that ephrinA4 binding sites may serve as a target for pharmacological treatment of fear and anxiety disorders.
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Lamprecht R. The actin cytoskeleton in memory formation. Prog Neurobiol 2014; 117:1-19. [DOI: 10.1016/j.pneurobio.2014.02.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 02/02/2014] [Accepted: 02/03/2014] [Indexed: 01/21/2023]
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Remaud J, Ceccom J, Carponcy J, Dugué L, Menchon G, Pech S, Halley H, Francés B, Dahan L. Anisomycin injection in area CA3 of the hippocampus impairs both short-term and long-term memories of contextual fear. Learn Mem 2014; 21:311-5. [PMID: 25171422 PMCID: PMC4024620 DOI: 10.1101/lm.033969.113] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Protein synthesis is involved in the consolidation of short-term memory into long-term memory. Previous electrophysiological data concerning LTP in CA3 suggest that protein synthesis in that region might also be necessary for short-term memory. We tested this hypothesis by locally injecting the protein synthesis inhibitor anisomycin in hippocampal area CA1 or CA3 immediately after contextual fear conditioning. As previously shown, injections in CA1 impaired long-term memory but spared short-term memory. Conversely, injections in CA3 impaired both long-term and short-term memories. We conclude that early steps of experience-induced plasticity occurring in CA3 and underlying short-term memory require protein synthesis.
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Affiliation(s)
- Jessica Remaud
- Université de Toulouse (UPS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France Centre National de la Recherche Scientifique (CNRS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France
| | - Johnatan Ceccom
- Université de Toulouse (UPS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France Centre National de la Recherche Scientifique (CNRS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France
| | - Julien Carponcy
- Université de Toulouse (UPS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France Centre National de la Recherche Scientifique (CNRS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France
| | - Laura Dugué
- Université de Toulouse (UPS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France Centre National de la Recherche Scientifique (CNRS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France
| | - Gregory Menchon
- Université de Toulouse (UPS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France Centre National de la Recherche Scientifique (CNRS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France
| | - Stéphane Pech
- Université de Toulouse (UPS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France Centre National de la Recherche Scientifique (CNRS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France
| | - Helene Halley
- Université de Toulouse (UPS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France Centre National de la Recherche Scientifique (CNRS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France
| | - Bernard Francés
- Université de Toulouse (UPS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France Centre National de la Recherche Scientifique (CNRS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France
| | - Lionel Dahan
- Université de Toulouse (UPS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France Centre National de la Recherche Scientifique (CNRS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse, France
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Integrin dynamics produce a delayed stage of long-term potentiation and memory consolidation. J Neurosci 2012; 32:12854-61. [PMID: 22973009 DOI: 10.1523/jneurosci.2024-12.2012] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Memory consolidation theory posits that newly acquired information passes through a series of stabilization steps before being firmly encoded. We report here that in rat and mouse, hippocampus cell adhesion receptors belonging to the β1-integrin family exhibit dynamic properties in adult synapses and that these contribute importantly to a previously unidentified stage of consolidation. Quantitative dual immunofluorescence microscopy showed that induction of long-term potentiation (LTP) by theta burst stimulation (TBS) activates β1 integrins, and integrin-signaling kinases, at spine synapses in adult hippocampal slices. Neutralizing antisera selective for β1 integrins blocked these effects. TBS-induced integrin activation was brief (<7 min) and followed by an ∼45 min period during which the adhesion receptors did not respond to a second application of TBS. Brefeldin A, which blocks integrin trafficking to the plasma membrane, prevented the delayed recovery of integrin responses to TBS. β1 integrin-neutralizing antisera erased LTP when applied during, but not after, the return of integrin responsivity. Similarly, infusions of anti-β1 into rostral mouse hippocampus blocked formation of long-term, object location memory when started 20 min after learning but not 40 min later. The finding that β1 integrin neutralization was effective in the same time window for slice and behavioral experiments strongly suggests that integrin recovery triggers a temporally discrete, previously undetected second stage of consolidation for both LTP and memory.
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A role for hippocampal actin rearrangement in object placement memory in female rats. Neurobiol Learn Mem 2012; 98:284-90. [PMID: 23010136 DOI: 10.1016/j.nlm.2012.09.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 09/10/2012] [Accepted: 09/13/2012] [Indexed: 01/12/2023]
Abstract
Actin rearrangement, the polymerization of globular actin (G-actin) to filamentous actin, causes morphological changes in dendritic spines and is hypothesized to be a substrate of learning and memory. The ovarian hormone estradiol promotes hippocampal actin rearrangement and enhances performance on hippocampus-dependent tasks, including object placement memory. The goals of the current study were to determine a role for actin rearrangement and its regulatory pathway in object placement memory in female rats and to determine if estradiol impacts actin rearrangement in ovariectomized rats during the performance of the task. In an initial experiment, young adult Long-Evans rats were ovariectomized and implanted with capsules containing either cholesterol vehicle or estradiol. Bilateral intrahippocampal infusions of aCSF vehicle or the actin rearrangement inhibitor, latrunculin A, were administered 15 min prior to initiation of the object placement task. Latrunculin A dose-dependently impaired object placement memory. Estradiol had no impact on the ability of latrunculin A to affect performance. In a second experiment, rats were ovariectomized and received implants containing cholesterol or estradiol. Half of each hormone treatment group was exposed to the object placement memory task and half underwent control procedures. Immediately following completion of behavior, rats were euthanized and hippocampi removed. Western blotting was used to measure hippocampal levels of phosphorylated and total levels of a regulator of actin polymerization, the actin depolymerization factor cofilin. Exposure to the object placement memory task resulted in significant increases in phosphorylated levels of cofilin. Estradiol treatment had no impact on protein levels. These data support a role for hippocampal actin rearrangement and its regulatory proteins in object placement memory in female rats and suggest that chronic estradiol treatment does not impact hippocampal actin arrangement.
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Lamprecht R. The roles of the actin cytoskeleton in fear memory formation. Front Behav Neurosci 2011; 5:39. [PMID: 21808614 PMCID: PMC3139223 DOI: 10.3389/fnbeh.2011.00039] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2011] [Accepted: 07/02/2011] [Indexed: 01/08/2023] Open
Abstract
The formation and storage of fear memory is needed to adapt behavior and avoid danger during subsequent fearful events. However, fear memory may also play a significant role in stress and anxiety disorders. When fear becomes disproportionate to that necessary to cope with a given stimulus, or begins to occur in inappropriate situations, a fear or anxiety disorder exists. Thus, the study of cellular and molecular mechanisms underpinning fear memory may shed light on the formation of memory and on anxiety and stress related disorders. Evidence indicates that fear learning leads to changes in neuronal synaptic transmission and morphology in brain areas underlying fear memory formation including the amygdala and hippocampus. The actin cytoskeleton has been shown to participate in these key neuronal processes. Recent findings show that the actin cytoskeleton is needed for fear memory formation and extinction. Moreover, the actin cytoskeleton is involved in synaptic plasticity and in neuronal morphogenesis in brain areas that mediate fear memory. The actin cytoskeleton may therefore mediate between synaptic transmission during fear learning and long-term cellular alterations mandatory for fear memory formation.
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Affiliation(s)
- Raphael Lamprecht
- Faculty of Natural Sciences, Department of Neurobiology and Ethology, University of Haifa Haifa, Israel
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Contextual learning requires synaptic AMPA receptor delivery in the hippocampus. Proc Natl Acad Sci U S A 2011; 108:12503-8. [PMID: 21746893 DOI: 10.1073/pnas.1104558108] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The hippocampus plays a central role in learning and memory. Although synaptic delivery of AMPA-type glutamate receptors (AMPARs) contributes to experience-dependent synaptic strengthening, its role in hippocampus-dependent learning remains elusive. By combining viral-mediated in vivo gene delivery with in vitro patch-clamp recordings, we found that the inhibitory avoidance task, a hippocampus-dependent contextual fear-learning paradigm, delivered GluR1-containing AMPARs into CA3-CA1 synapses of the dorsal hippocampus. To block the synaptic delivery of endogenous AMPARs, we expressed a fragment of the GluR1-cytoplasmic tail (the 14-aa GluR1 membrane-proximal region with two serines mutated to phospho-mimicking aspartates: MPR-DD). MPR-DD prevented learning-driven synaptic AMPAR delivery in CA1 neurons. Bilateral expression of MPR-DD in the CA1 region of the rat impaired inhibitory avoidance learning, indicating that synaptic GluR1 trafficking in the CA1 region of the hippocampus is required for encoding contextual fear memories. The fraction of CA1 neurons that underwent synaptic strengthening positively correlated with the performance in the inhibitory avoidance fear memory task. These data suggest that the robustness of a contextual memory depends on the number of hippocampal neurons that participate in the encoding of a memory trace.
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