1
|
Brito DVC, Kupke J, Sokolov R, Cambridge S, Both M, Bengtson CP, Rozov A, Oliveira AMM. Biphasic Npas4 expression promotes inhibitory plasticity and suppression of fear memory consolidation in mice. Mol Psychiatry 2024; 29:1929-1940. [PMID: 38347124 PMCID: PMC11408256 DOI: 10.1038/s41380-024-02454-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 01/17/2024] [Accepted: 01/23/2024] [Indexed: 02/19/2024]
Abstract
Long-term memories are believed to be encoded by unique transcriptional signatures in the brain. The expression of immediate early genes (IEG) promotes structural and molecular changes required for memory consolidation. Recent evidence has shown that the brain is equipped with mechanisms that not only promote, but actively constrict memory formation. However, it remains unknown whether IEG expression may play a role in memory suppression. Here we uncovered a novel function of the IEG neuronal PAS domain protein 4 (Npas4), as an inducible memory suppressor gene of highly salient aversive experiences. Using a contextual fear conditioning paradigm, we found that low stimulus salience leads to monophasic Npas4 expression, while highly salient learning induces a biphasic expression of Npas4 in the hippocampus. The later phase requires N-methyl-D-aspartate (NMDA) receptor activity and is independent of dopaminergic neurotransmission. Our in vivo pharmacological and genetic manipulation experiments suggested that the later phase of Npas4 expression restricts the consolidation of a fear memory and promote behavioral flexibility, by facilitating fear extinction and the contextual specificity of fear responses. Moreover, immunofluorescence and electrophysiological analysis revealed a concomitant increase in synaptic input from cholecystokinin (CCK)-expressing interneurons. Our results demonstrate how salient experiences evoke unique temporal patterns of IEG expression that fine-tune memory consolidation. Moreover, our study provides evidence for inducible gene expression associated with memory suppression as a possible mechanism to balance the consolidation of highly salient memories, and thereby to evade the formation of maladaptive behavior.
Collapse
Affiliation(s)
- David V C Brito
- Department of Neurobiology, Interdisciplinary Center for Neurosciences (IZN), Heidelberg University, 69120, Heidelberg, Germany
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139, Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, 8005-139, Faro, Portugal
| | - Janina Kupke
- Department of Neurobiology, Interdisciplinary Center for Neurosciences (IZN), Heidelberg University, 69120, Heidelberg, Germany
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam, 1081 HV, the Netherlands
| | - Rostilav Sokolov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997, Moscow, Russia
- Federal Center of Brain Research and Neurotechnology, 117513, Moscow, Russia
- Institute of Neuroscience, Lobachevsky State University of Nizhniy Novgorod, Nizhny, Novgorod, Russia
| | - Sidney Cambridge
- Anatomy II, Dr. Senckenberg Anatomy, Goethe-University Frankfurt, 60590, Frankfurt am Main, Germany
| | - Martin Both
- Institute of Physiology and Pathophysiology, Medical Faculty, Heidelberg University, 69120, Heidelberg, Germany
| | - C Peter Bengtson
- Department of Neurobiology, Interdisciplinary Center for Neurosciences (IZN), Heidelberg University, 69120, Heidelberg, Germany
| | - Andrei Rozov
- Federal Center of Brain Research and Neurotechnology, 117513, Moscow, Russia
- Institute of Physiology and Pathophysiology, Medical Faculty, Heidelberg University, 69120, Heidelberg, Germany
- OpenLab of Neurobiology, Kazan Federal University, 420008, Kazan, Russia
| | - Ana M M Oliveira
- Department of Neurobiology, Interdisciplinary Center for Neurosciences (IZN), Heidelberg University, 69120, Heidelberg, Germany.
- Department of Molecular and Cellular Cognition Research, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, 68159, Mannheim, Germany.
| |
Collapse
|
2
|
Granja-Galeano G, Dominguez-Rubio AP, Zappia CD, Wolfson M, Sanz-Blasco S, Aisemberg J, Zorrilla-Zubilete M, Fernandez N, Franchi A, Fitzsimons CP, Monczor F. CB1 receptor expression and signaling are required for dexamethasone-induced aversive memory consolidation. Neuropharmacology 2023; 239:109674. [PMID: 37541383 DOI: 10.1016/j.neuropharm.2023.109674] [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: 12/14/2022] [Revised: 07/12/2023] [Accepted: 07/27/2023] [Indexed: 08/06/2023]
Abstract
The molecular processes that underlie long-term memory formation involve signaling pathway activation by neurotransmitter release, which induces the expression of immediate early genes, such as Zif268, having a key role in memory formation. In this work, we show that the cannabinoid CB1 receptor signaling is necessary for the effects of dexamethasone on the behavioral response in an inhibitory avoidance task, on dexamethasone-induced ERK phosphorylation, and on dexamethasone-dependent Zif268 expression. Furthermore, we provide primary evidence for the mechanism responsible for this crosstalk between cannabinoid and glucocorticoid-mediated signaling pathways, showing that dexamethasone regulates endocannabinoid metabolism by inhibiting the activity of the Fatty acid amide hydrolase (FAAH), an integral membrane enzyme that hydrolyzes endocannabinoids and related amidated signaling lipids. Our results provide novel evidence regarding the role of the endocannabinoid system, and in particular of the CB1 receptor, as a mediator of the effects of glucocorticoids on the consolidation of aversive memories.
Collapse
Affiliation(s)
- Gina Granja-Galeano
- Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, 1113, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigaciones Farmacológicas (ININFA), Universidad de Buenos Aires, Buenos Aires, 1113, Argentina
| | - Ana Paula Dominguez-Rubio
- Laboratorio de Fisiopatología de la Preñez y el Parto, Centro de Estudios Farmacológicos y Botánicos (CEFyBO-UBA/CONICET). Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - C Daniel Zappia
- Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, 1113, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigaciones Farmacológicas (ININFA), Universidad de Buenos Aires, Buenos Aires, 1113, Argentina
| | - Manuel Wolfson
- Laboratorio de Fisiopatología de la Preñez y el Parto, Centro de Estudios Farmacológicos y Botánicos (CEFyBO-UBA/CONICET). Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Sara Sanz-Blasco
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigaciones Farmacológicas (ININFA), Universidad de Buenos Aires, Buenos Aires, 1113, Argentina
| | - Julieta Aisemberg
- Laboratorio de Fisiopatología de la Preñez y el Parto, Centro de Estudios Farmacológicos y Botánicos (CEFyBO-UBA/CONICET). Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Maria Zorrilla-Zubilete
- Laboratorio de Fisiopatología de la Preñez y el Parto, Centro de Estudios Farmacológicos y Botánicos (CEFyBO-UBA/CONICET). Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Natalia Fernandez
- Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, 1113, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigaciones Farmacológicas (ININFA), Universidad de Buenos Aires, Buenos Aires, 1113, Argentina
| | - Ana Franchi
- Laboratorio de Fisiopatología de la Preñez y el Parto, Centro de Estudios Farmacológicos y Botánicos (CEFyBO-UBA/CONICET). Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Carlos P Fitzsimons
- Center for Neuroscience, Faculty of Science, Swammerdam Institute for Life Sciences, University of Amsterdam, 1098 XH, Amsterdam, the Netherlands
| | - Federico Monczor
- Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, 1113, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigaciones Farmacológicas (ININFA), Universidad de Buenos Aires, Buenos Aires, 1113, Argentina.
| |
Collapse
|
3
|
Swilley C, Lin Y, Zheng Y, Xu X, Liu M, Jarome T, Hodes GE, Xie H. Sex linked behavioral and hippocampal transcriptomic changes in mice with cell-type specific Egr1 loss. Front Neurosci 2023; 17:1240209. [PMID: 37928724 PMCID: PMC10623684 DOI: 10.3389/fnins.2023.1240209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 10/03/2023] [Indexed: 11/07/2023] Open
Abstract
The transcription factor EGR1 is instrumental in numerous neurological processes, encompassing learning and memory as well as the reaction to stress. Egr1 complete knockout mice demonstrate decreased depressive or anxiety-like behavior and impaired performance in spatial learning and memory. Nevertheless, the specific functions of Egr1 in distinct cell types have been largely underexplored. In this study, we cataloged the behavioral and transcriptomic character of Nestin-Cre mediated Egr1 conditional knockout (Egr1cKO) mice together with their controls. Although the conditional knockout did not change nociceptive or anxiety responses, it triggered changes in female exploratory activity during anxiety testing. Hippocampus-dependent spatial learning in the object location task was unaffected, but female Egr1cKO mice did exhibit poorer retention during testing on a contextual fear conditioning task compared to males. RNA-seq data analyses revealed that the presence of the floxed Egr1 cassette or Nestin-Cre driver alone exerts a subtle influence on hippocampal gene expression. The sex-related differences were amplified in Nestin-Cre mediated Egr1 conditional knockout mice and female mice are more sensitive to the loss of Egr1 gene. Differentially expressed genes resulted from the loss of Egr1 in neuronal cell lineage were significantly associated with the regulation of Wnt signaling pathway, extracellular matrix, and axon guidance. Altogether, our results demonstrate that Nestin-Cre and the loss of Egr1 in neuronal cell lineage have distinct impacts on hippocampal gene expression in a sex-specific manner.
Collapse
Affiliation(s)
- Cody Swilley
- Epigenomics and Computational Biology Lab, Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, United States
| | - Yu Lin
- Epigenomics and Computational Biology Lab, Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
- Genetics, Bioinformatics and Computational Biology Program, Virginia Tech, Blacksburg, VA, United States
| | - Yuze Zheng
- Epigenomics and Computational Biology Lab, Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
| | - Xiguang Xu
- Epigenomics and Computational Biology Lab, Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, United States
| | - Min Liu
- Epigenomics and Computational Biology Lab, Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, United States
| | - Timothy Jarome
- School of Animal Sciences, Virginia Tech, Blacksburg, VA, United States
- School of Neuroscience, Virginia Tech, Blacksburg, VA, United States
| | - Georgia E. Hodes
- School of Neuroscience, Virginia Tech, Blacksburg, VA, United States
| | - Hehuang Xie
- Epigenomics and Computational Biology Lab, Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, United States
- Genetics, Bioinformatics and Computational Biology Program, Virginia Tech, Blacksburg, VA, United States
- School of Neuroscience, Virginia Tech, Blacksburg, VA, United States
| |
Collapse
|
4
|
Wang W, Wang Z, Cao J, Dong Y, Chen Y. Roles of Rac1-Dependent Intrinsic Forgetting in Memory-Related Brain Disorders: Demon or Angel. Int J Mol Sci 2023; 24:10736. [PMID: 37445914 DOI: 10.3390/ijms241310736] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 06/14/2023] [Accepted: 06/21/2023] [Indexed: 07/15/2023] Open
Abstract
Animals are required to handle daily massive amounts of information in an ever-changing environment, and the resulting memories and experiences determine their survival and development, which is critical for adaptive evolution. However, intrinsic forgetting, which actively deletes irrelevant information, is equally important for memory acquisition and consolidation. Recently, it has been shown that Rac1 activity plays a key role in intrinsic forgetting, maintaining the balance of the brain's memory management system in a controlled manner. In addition, dysfunctions of Rac1-dependent intrinsic forgetting may contribute to memory deficits in neurological and neurodegenerative diseases. Here, these new findings will provide insights into the neurobiology of memory and forgetting, pathological mechanisms and potential therapies for brain disorders that alter intrinsic forgetting mechanisms.
Collapse
Affiliation(s)
- Wei Wang
- Neurobiology Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Zixu Wang
- Neurobiology Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Jing Cao
- Neurobiology Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Yulan Dong
- Neurobiology Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Yaoxing Chen
- Neurobiology Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
- Key Laboratory of Precision Nutrition and Food Quality, Key Laboratory of Functional Dairy, Ministry of Education, Beijing Laboratory of Food Quality and Safety, Department of Nutrition and Health, China Agricultural University, Beijing 100083, China
| |
Collapse
|
5
|
Transcriptome Profiling in the Hippocampi of Mice with Experimental Autoimmune Encephalomyelitis. Int J Mol Sci 2022; 23:ijms232314829. [PMID: 36499161 PMCID: PMC9738199 DOI: 10.3390/ijms232314829] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/16/2022] [Accepted: 11/24/2022] [Indexed: 12/03/2022] Open
Abstract
Experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), approximates the key histopathological, clinical, and immunological features of MS. Hippocampal dysfunction in MS and EAE causes varying degrees of cognitive and emotional impairments and synaptic abnormalities. However, the molecular alterations underlying hippocampal dysfunctions in MS and EAE are still under investigation. The purpose of this study was to identify differentially expressed genes (DEGs) in the hippocampus of mice with EAE in order to ascertain potential genes associated with hippocampal dysfunction. Gene expression in the hippocampus was analyzed by RNA-sequencing and validated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Gene expression analysis revealed 1202 DEGs; 1023 were upregulated and 179 were downregulated in the hippocampus of mice with EAE (p-value < 0.05 and fold change >1.5). Gene ontology (GO) analysis showed that the upregulated genes in the hippocampi of mice with EAE were associated with immune system processes, defense responses, immune responses, and regulation of immune responses, whereas the downregulated genes were related to learning or memory, behavior, and nervous system processes in the GO biological process. The expressions of hub genes from the search tool for the retrieval of interacting genes/proteins (STRING) analysis were validated by RT-qPCR. Additionally, gene set enrichment analysis showed that the upregulated genes in the hippocampus were associated with inflammatory responses: interferon-γ responses, allograft rejection, interferon-α responses, IL6_JAK_STAT3 signaling, inflammatory responses, complement, IL2_STAT5 signaling, TNF-α signaling via NF-κB, and apoptosis, whereas the downregulated genes were related to synaptic plasticity, dendritic development, and development of dendritic spine. This study characterized the transcriptome pattern in the hippocampi of mice with EAE and signaling pathways underpinning hippocampal dysfunction. However, further investigation is needed to determine the applicability of these findings from this rodent model to patients with MS. Collectively, these results indicate directions for further research to understand the mechanisms behind hippocampal dysfunction in EAE.
Collapse
|
6
|
Inhibition of late mRNA synthesis in the hippocampus impairs consolidation and reconsolidation of spatial memory in male rats. Neurobiol Learn Mem 2022; 195:107687. [DOI: 10.1016/j.nlm.2022.107687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 10/06/2022] [Accepted: 10/07/2022] [Indexed: 11/19/2022]
|
7
|
Reyes-Resina I, Samer S, Kreutz MR, Oelschlegel AM. Molecular Mechanisms of Memory Consolidation That Operate During Sleep. Front Mol Neurosci 2021; 14:767384. [PMID: 34867190 PMCID: PMC8636908 DOI: 10.3389/fnmol.2021.767384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 10/27/2021] [Indexed: 11/17/2022] Open
Abstract
The role of sleep for brain function has been in the focus of interest for many years. It is now firmly established that sleep and the corresponding brain activity is of central importance for memory consolidation. Less clear are the underlying molecular mechanisms and their specific contribution to the formation of long-term memory. In this review, we summarize the current knowledge of such mechanisms and we discuss the several unknowns that hinder a deeper appreciation of how molecular mechanisms of memory consolidation during sleep impact synaptic function and engram formation.
Collapse
Affiliation(s)
- Irene Reyes-Resina
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Sebastian Samer
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Michael R Kreutz
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Leibniz Group 'Dendritic Organelles and Synaptic Function', Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Center for Behavioral Brain Sciences, Otto von Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Anja M Oelschlegel
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany
| |
Collapse
|
8
|
Heroux NA, Horgan CJ, Rosen JB, Stanton ME. Cholinergic rescue of neurocognitive insult following third-trimester equivalent alcohol exposure in rats. Neurobiol Learn Mem 2019; 163:107030. [PMID: 31185278 PMCID: PMC6689250 DOI: 10.1016/j.nlm.2019.107030] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 05/22/2019] [Accepted: 06/02/2019] [Indexed: 12/28/2022]
Abstract
Neonatal ethanol exposure during the third trimester equivalent of human pregnancy in the rat significantly impairs hippocampal and prefrontal neurobehavioral functioning. Postnatal day [PD] 4-9 ethanol exposure in rats disrupts long-term context memory formation, resulting in abolished post-shock and retention test freezing in a variant of contextual fear conditioning called the Context Preexposure Facilitation Effect (CPFE). This behavioral impairment is accompanied by disrupted medial prefrontal, but not dorsal hippocampal expression of the immediate early genes (IEGs) c-Fos, Arc, Egr-1, and Npas4 (Heroux, Robinson-Drummer, Kawan, Rosen, & Stanton, 2019). The current experiment examined if systemic administration of the acetylcholinesterase inhibitor physostigmine (PHY) prior to context learning would rescue prefrontal IEG expression and freezing in the CPFE. From PD4-9, Long-Evans rats received oral intubation of ethanol (EtOH; 5.25 g/kg/day) or sham-intubation (SI). Rats received a systemic injection of saline (SAL) or PHY (0.01 mg/kg) prior to all three phases (Experiment 1) or just context exposure (Experiment 2) in the CPFE from PD31-33. A subset of rats were sacrificed 30 min after context learning to assay changes in IEG expression in the medial prefrontal cortex (mPFC), dorsal hippocampus (dHPC), and ventral hippocampus (vHPC). Administration of PHY prior to all three phases or just context learning rescued both post-shock and retention test freezing in the CPFE in EtOH rats without altering performance in SI rats. EtOH-SAL rats had significantly reduced mPFC but not dHPC expression of c-Fos, Arc, Egr-1, and Npas4. EtOH-PHY treatment rescued mPFC expression of c-Fos in ethanol-exposed rats and increased Arc and Npas4 regardless of dosing condition. While there was no effect of PHY on dHPC or vHPC expression of Arc, Egr-1, or Npas4, this treatment significantly boosted hippocampal expression of c-Fos regardless of ethanol treatment. These findings implicate impaired cholinergic and prefrontal function in cognitive deficits arising from 3rd-trimester equivalent alcohol exposure.
Collapse
Affiliation(s)
- Nicholas A Heroux
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716, United States.
| | - Colin J Horgan
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716, United States
| | - Jeffrey B Rosen
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716, United States
| | - Mark E Stanton
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716, United States
| |
Collapse
|
9
|
Yang W, Guo Q, Li J, Wang X, Pan B, Wang Y, Wu L, Yan J, Cheng Z. microRNA-124 attenuates isoflurane-induced neurological deficits in neonatal rats via binding to EGR1. J Cell Physiol 2019; 234:23017-23032. [PMID: 31131895 DOI: 10.1002/jcp.28862] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/26/2019] [Accepted: 03/06/2019] [Indexed: 12/30/2022]
Abstract
Isoflurane anesthesia induces neuroapoptosis in the development of the brain. In this study, neonatal rats and hippocampal neurons were subjected to isoflurane exposure, in which the effect of miR-124 on the neurological deficits induced by isoflurane was evaluated. Isoflurane anesthesia models were induced in neonatal SD rats aged 7 days and then treated with miR-124 agomir, miR-124 antagomir, or LV-CMV-early growth response 1 (EGR1) plasmids. Then, the spatial learning and memory ability of rats were evaluated by Morris water maze. Furthermore, primary hippocampal neurons cultured 7 days were also exposed to isoflurane and transfected with miR-124 agomir, miR-124 antagomir, or LV-CMV-EGR1 plasmids. The targeting relationship of miR-124 and EGR1 was verified by the dual-luciferase reporter gene assay. To identify the effect of miR-124 on neuron activities, the viability and apoptosis of hippocampal neurons were assessed. In response to isoflurane exposure, miR-124 expression was reduced and EGR1 expression was increased in the hippocampal tissues and neurons. The isoflurane anesthesia damaged rats' spatial learning and memory ability, and reduced viability, and promoted apoptosis of hippocampal neurons. EGR1 was targeted and negatively regulated by miR-124. The treatment of miR-124 agomir improved rats' spatial learning and memory ability and notably increased hippocampal neuron viability and resistance to apoptosis, corresponding to an increased brain-derived neurotrophic factor (BDNF) expression, inhibited expression of proapoptotic factors (cleaved-Caspase-3 and Bax), and enhanced the expression of antiapoptotic factor (Bcl-2). Upregulated miR-124 inhibited the expression of EGR1, by which mechanism miR-124 reduced the neurological deficits induced by isoflurane in neonatal rats through inhibiting apoptosis of hippocampal neurons.
Collapse
Affiliation(s)
- Wenqian Yang
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, P.R. China
| | - Qulian Guo
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, P.R. China
| | - Jingyi Li
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, P.R. China
| | - Ximei Wang
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, P.R. China
| | - Bingbing Pan
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, P.R. China
| | - Yunjiao Wang
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, P.R. China
| | - Lei Wu
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, P.R. China
| | - Jianqin Yan
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, P.R. China
| | - Zhigang Cheng
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, P.R. China
| |
Collapse
|
10
|
Piazza FV, Segabinazi E, de Meireles ALF, Mega F, Spindler CDF, Augustin OA, Salvalaggio GDS, Achaval M, Kruse MS, Coirini H, Marcuzzo S. Severe Uncontrolled Maternal Hyperglycemia Induces Microsomia and Neurodevelopment Delay Accompanied by Apoptosis, Cellular Survival, and Neuroinflammatory Deregulation in Rat Offspring Hippocampus. Cell Mol Neurobiol 2019; 39:401-414. [PMID: 30739252 DOI: 10.1007/s10571-019-00658-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 01/30/2019] [Indexed: 12/14/2022]
Abstract
Maternal diabetes constitutes an unfavorable intrauterine environment for offspring development. Although it is known that diabetes can cause brain alterations and increased risk for neurologic disorders, the relationship between neuroimmune activation, brain changes, and neurodevelopment deficits in the offspring remains unclear. In order to elucidate the short- and long-term biological basis of the developmental outcomes caused by the severe uncontrolled maternal hyperglycemia, we studied apoptosis, neurogenesis, and neuroinflammation pathways in the hippocampus of neonates and young rats born to diabetic dams. Diabetes was induced on gestational day 5 by an injection of streptozotocin. Evaluations of milestones, body growth, and inhibitory avoidance were performed to monitor the offspring development and behavior. Hippocampal modifications were studied through cellular survival by BrdU in the dentate gyrus, expression of apoptosis-regulatory proteins (procaspase 3, caspase 3, and Bcl-2), BDNF, and neuroinflammatory modulation by interleukins, MHC-I, MHC-II, Iba-1, and GFAP proteins. Severe maternal diabetes caused microsomia and neurodevelopmental delay in pups and decrease of Bcl-2, procaspase 3, and caspase 3 in the hippocampus. Moreover, in a later stage of development, it was found an increase of TNF-α and a decrease of procaspase 3, caspase 3, MHC-I, IL-1β, and BDNF in the hippocampus, as well as impairment in cellular survival in the dentate gyrus. This study showed significant short- and long-term commitments on the development, apoptosis, cell survival, and neuroinflammation in the offspring hippocampus induced by severe uncontrolled maternal hyperglycemia. The data reinforce the need for treatment of maternal hyperglycemic states during pregnancy and breast-feeding.
Collapse
Affiliation(s)
- Francele Valente Piazza
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, Porto Alegre, RS, CEP 90050-170, Brazil.
- Laboratório de Histofisiologia Comparada, Departamento de Ciências Morfológicas, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, sala 142, Porto Alegre, RS, CEP 90050-170, Brazil.
| | - Ethiane Segabinazi
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, Porto Alegre, RS, CEP 90050-170, Brazil
- Laboratório de Histofisiologia Comparada, Departamento de Ciências Morfológicas, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, sala 142, Porto Alegre, RS, CEP 90050-170, Brazil
| | - André Luís Ferreira de Meireles
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, Porto Alegre, RS, CEP 90050-170, Brazil
- Laboratório de Histofisiologia Comparada, Departamento de Ciências Morfológicas, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, sala 142, Porto Alegre, RS, CEP 90050-170, Brazil
| | - Filipe Mega
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, Porto Alegre, RS, CEP 90050-170, Brazil
- Laboratório de Histofisiologia Comparada, Departamento de Ciências Morfológicas, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, sala 142, Porto Alegre, RS, CEP 90050-170, Brazil
| | - Christiano de Figueiredo Spindler
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, Porto Alegre, RS, CEP 90050-170, Brazil
- Laboratório de Histofisiologia Comparada, Departamento de Ciências Morfológicas, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, sala 142, Porto Alegre, RS, CEP 90050-170, Brazil
| | - Otávio Américo Augustin
- Laboratório de Histofisiologia Comparada, Departamento de Ciências Morfológicas, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, sala 142, Porto Alegre, RS, CEP 90050-170, Brazil
| | - Gabriela Dos Santos Salvalaggio
- Laboratório de Histofisiologia Comparada, Departamento de Ciências Morfológicas, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, sala 142, Porto Alegre, RS, CEP 90050-170, Brazil
| | - Matilde Achaval
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, Porto Alegre, RS, CEP 90050-170, Brazil
- Laboratório de Histofisiologia Comparada, Departamento de Ciências Morfológicas, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, sala 142, Porto Alegre, RS, CEP 90050-170, Brazil
| | - Maria Sol Kruse
- Laboratorio de Neurobiología, Instituto de Biología y Medicina Experimental, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
| | - Héctor Coirini
- Laboratorio de Neurobiología, Instituto de Biología y Medicina Experimental, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
- Departamento de Bioquímica Humana, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, 5to Piso, C1121ABG, Buenos Aires, Argentina
| | - Simone Marcuzzo
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, Porto Alegre, RS, CEP 90050-170, Brazil
- Laboratório de Histofisiologia Comparada, Departamento de Ciências Morfológicas, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite 500, sala 142, Porto Alegre, RS, CEP 90050-170, Brazil
| |
Collapse
|
11
|
Blocking H2A.Z Incorporation via Tip60 Inhibition Promotes Systems Consolidation of Fear Memory in Mice. eNeuro 2018; 5:eN-CFN-0378-18. [PMID: 30417078 PMCID: PMC6223110 DOI: 10.1523/eneuro.0378-18.2018] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 10/12/2018] [Indexed: 01/08/2023] Open
Abstract
Memory formation is a protracted process that initially involves the hippocampus and becomes increasingly dependent on the cortex over time, but the mechanisms of this transfer are unclear. We recently showed that hippocampal depletion of the histone variant H2A.Z enhances both recent and remote memories, but the use of virally mediated depletion reduced H2A.Z levels throughout testing, making its temporally specific function unclear. Given the lack of drugs that target histone variants, we tested existing drugs for efficacy against H2A.Z based on their targeting of known H2A.Z regulators. The Tip60 (part of H2A.Z deposition complex) inhibitor Nu9056 reduced H2A.Z binding, whereas the histone deacetylase (HDAC) inhibitor Trichostatin-A increased H2A.Z acetylation without influencing total H2A.Z in cultured hippocampal neurons. Tip60 (but not HDAC) inhibition 23 h after learning enhanced remote (tested at 7 d) and not recent (tested at 24 h) contextual fear memory in mice. In contrast, Tip60 inhibition 30 d after learning impaired recall of remote memory after 1 h, but protected the memory from further decline 24 h later. These data provide the first evidence of a delayed postlearning role for histone variants in supporting memory transfer during systems consolidation.
Collapse
|
12
|
Medina JH, Viola H. ERK1/2: A Key Cellular Component for the Formation, Retrieval, Reconsolidation and Persistence of Memory. Front Mol Neurosci 2018; 11:361. [PMID: 30344477 PMCID: PMC6182090 DOI: 10.3389/fnmol.2018.00361] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 09/12/2018] [Indexed: 11/26/2022] Open
Abstract
Extracellular regulated kinase 1/2 (ERK1/2) has been strongly implicated in several cellular processes. In the brain ERK1/2 activity has been primarily involved in long-term memory (LTM) formation and expression. Here, we review earlier evidence and describe recent developments of ERK1/2 signaling in memory processing focusing the attention on the role of ERK1/2 in memory retrieval and reconsolidation, and in the maintenance of the memory trace including mechanisms involving the protection of labile memories. In addition, relearning requires ERK1/2 activity in selected brain regions. Its involvement in distinct memory stages points at ERK1/2 as a core element in memory processing and as one likely target to treat memory impairments associated with neurological disorders.
Collapse
Affiliation(s)
- Jorge H Medina
- Instituto de Biología Celular y Neurociencias (IBCN) "Dr Eduardo De Robertis", CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Haydee Viola
- Instituto de Biología Celular y Neurociencias (IBCN) "Dr Eduardo De Robertis", CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina.,Departamento de Fisiología, Biología Molecular y Celular "Dr. Hector Maldonado" (FBMC), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| |
Collapse
|
13
|
Kyrke-Smith M, Williams JM. Bridging Synaptic and Epigenetic Maintenance Mechanisms of the Engram. Front Mol Neurosci 2018; 11:369. [PMID: 30344478 PMCID: PMC6182070 DOI: 10.3389/fnmol.2018.00369] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 09/18/2018] [Indexed: 12/27/2022] Open
Abstract
How memories are maintained, and how memories are lost during aging or disease, are intensely investigated issues. Arguably, the reigning theory is that synaptic modifications allow for the formation of engrams during learning, and sustaining engrams sustains memory. Activity-regulated gene expression profiles have been shown to be critical to these processes, and their control by the epigenome has begun to be investigated in earnest. Here, we propose a novel theory as to how engrams are sustained. We propose that many of the genes that are currently believed to underlie long-term memory are actually part of a “plasticity transcriptome” that underpins structural and functional modifications to neuronal connectivity during the hours to days following learning. Further, we hypothesize that a “maintenance transcriptome” is subsequently induced that includes epigenetic negative regulators of gene expression, particularly histone deacetylases. The maintenance transcriptome negatively regulates the plasticity transcriptome, and thus the plastic capability of a neuron, after learning. In this way, the maintenance transcriptome would act as a metaplasticity mechanism that raises the threshold for change in neurons within an engram, helping to ensure the connectivity is stabilized and memory is maintained.
Collapse
Affiliation(s)
- Madeleine Kyrke-Smith
- Department of Anatomy, The Brain Health Research Centre, Brain Research New Zealand - Rangahau Roro Aotearoa, University of Otago, Dunedin, New Zealand.,Department of Psychology, The Brain Health Research Centre, Brain Research New Zealand - Rangahau Roro Aotearoa, University of Otago, Dunedin, New Zealand.,Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT, United States
| | - Joanna M Williams
- Department of Anatomy, The Brain Health Research Centre, Brain Research New Zealand - Rangahau Roro Aotearoa, University of Otago, Dunedin, New Zealand
| |
Collapse
|
14
|
Almeida-Filho DG, Queiroz CM, Ribeiro S. Memory corticalization triggered by REM sleep: mechanisms of cellular and systems consolidation. Cell Mol Life Sci 2018; 75:3715-3740. [PMID: 30054638 PMCID: PMC11105475 DOI: 10.1007/s00018-018-2886-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2018] [Revised: 06/27/2018] [Accepted: 07/19/2018] [Indexed: 01/29/2023]
Abstract
Once viewed as a passive physiological state, sleep is a heterogeneous and complex sequence of brain states with essential effects on synaptic plasticity and neuronal functioning. Rapid-eye-movement (REM) sleep has been shown to promote calcium-dependent plasticity in principal neurons of the cerebral cortex, both during memory consolidation in adults and during post-natal development. This article reviews the plasticity mechanisms triggered by REM sleep, with a focus on the emerging role of kinases and immediate-early genes for the progressive corticalization of hippocampus-dependent memories. The body of evidence suggests that memory corticalization triggered by REM sleep is a systemic phenomenon with cellular and molecular causes.
Collapse
Affiliation(s)
- Daniel G Almeida-Filho
- Brain Institute, Federal University of Rio Grande do Norte, Natal, RN, 59056-450, Brazil
| | - Claudio M Queiroz
- Brain Institute, Federal University of Rio Grande do Norte, Natal, RN, 59056-450, Brazil
| | - Sidarta Ribeiro
- Brain Institute, Federal University of Rio Grande do Norte, Natal, RN, 59056-450, Brazil.
| |
Collapse
|
15
|
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.
Collapse
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
| |
Collapse
|
16
|
Medina JH. Neural, Cellular and Molecular Mechanisms of Active Forgetting. Front Syst Neurosci 2018; 12:3. [PMID: 29467630 PMCID: PMC5808127 DOI: 10.3389/fnsys.2018.00003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 01/18/2018] [Indexed: 11/16/2022] Open
Abstract
The neurobiology of memory formation attracts much attention in the last five decades. Conversely, the rules that govern and the mechanisms underlying forgetting are less understood. In addition to retroactive interference, retrieval-induced forgetting and passive decay of time, it has been recently demonstrated that the nervous system has a diversity of active and inherent processes involved in forgetting. In Drosophila, some operate mainly at an early stage of memory formation and involves dopamine (DA) neurons, specific postsynaptic DA receptor subtypes, Rac1 activation and induces rapid active forgetting. In mammals, others regulate forgetting and persistence of seemingly consolidated memories and implicate the activity of DA receptor subtypes and AMPA receptors in the hippocampus (HP) and related structures to activate parallel signaling pathways controlling active time-dependent forgetting. Most of them may involve plastic changes in synaptic and extrasynaptic receptors including specific removal of GluA2 AMPA receptors. Forgetting at longer timescales might also include changes in adult neurogenesis in the dentate gyrus (DG) of the HP. Therefore, based on relevance or value considerations neuronal circuits may regulate in a time-dependent manner what is formed, stored, and maintained and what is forgotten.
Collapse
Affiliation(s)
- Jorge H Medina
- Laboratorio de Memoria, IBCN Universidad de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas (UBA-CONICET), Buenos Aires, Argentina.,Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| |
Collapse
|
17
|
Barry DN, Commins S. Temporal dynamics of immediate early gene expression during cellular consolidation of spatial memory. Behav Brain Res 2017; 327:44-53. [DOI: 10.1016/j.bbr.2017.03.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 03/04/2017] [Accepted: 03/09/2017] [Indexed: 01/05/2023]
|
18
|
Daily Life Experiences in Dreams and Sleep-Dependent Memory Consolidation. COGNITIVE NEUROSCIENCE OF MEMORY CONSOLIDATION 2017. [DOI: 10.1007/978-3-319-45066-7_10] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
19
|
Wang D, Mitchell ES. Cognition and Synaptic-Plasticity Related Changes in Aged Rats Supplemented with 8- and 10-Carbon Medium Chain Triglycerides. PLoS One 2016; 11:e0160159. [PMID: 27517611 PMCID: PMC4982641 DOI: 10.1371/journal.pone.0160159] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 07/14/2016] [Indexed: 12/25/2022] Open
Abstract
Brain glucose hypometabolism is a common feature of Alzheimer’s disease (AD). Previous studies have shown that cognition is improved by providing AD patients with an alternate energy source: ketones derived from either ketogenic diet or supplementation with medium chain triglycerides (MCT). Recently, data on the neuroprotective capacity of MCT-derived medium chain fatty acids (MCFA) suggest 8-carbon and 10-carbon MCFA may have cognition-enhancing properties which are not related to ketone production. We investigated the effect of 8 week treatment with MCT8, MCT10 or sunflower oil supplementation (5% by weight of chow diet) in 21 month old Wistar rats. Both MCT diets increased ketones plasma similarly compared to control diet, but MCT diets did not increase ketones in the brain. Treatment with MCT10, but not MCT8, significantly improved novel object recognition memory compared to control diet, while social recognition increased in both MCT groups. MCT8 and MCT10 diets decreased weight compared to control diet, where MCFA plasma levels were higher in MCT10 groups than in MCT8 groups. Both MCT diets increased IRS-1 (612) phosphorylation and decreased S6K phosphorylation (240/244) but only MCT10 increased Akt phosphorylation (473). MCT8 supplementation increased synaptophysin, but not PSD-95, in contrast MCT10 had no effect on either synaptic marker. Expression of Ube3a, which controls synaptic stability, was increased by both MCT diets. Cortex transcription via qPCR showed that immediate early genes related to synaptic plasticity (arc, plk3, junb, egr2, nr4a1) were downregulated by both MCT diets while MCT8 additionally down-regulated fosb and egr1 but upregulated grin1 and gba2. These results demonstrate that treatment of 8- and 10-carbon length MCTs in aged rats have slight differential effects on synaptic stability, protein synthesis and behavior that may be independent of brain ketone levels.
Collapse
Affiliation(s)
- Dongmei Wang
- Nestle Institute of Health Sciences, Cognitive Health and Aging, EPFL Innovation Park, Building H, 1015, Lausanne, Switzerland
| | - Ellen S. Mitchell
- Nestle Institute of Health Sciences, Cognitive Health and Aging, EPFL Innovation Park, Building H, 1015, Lausanne, Switzerland
- * E-mail:
| |
Collapse
|
20
|
Huckleberry KA, Kane GA, Mathis RJ, Cook SG, Clutton JE, Drew MR. Behavioral experience induces zif268 expression in mature granule cells but suppresses its expression in immature granule cells. Front Syst Neurosci 2015; 9:118. [PMID: 26347620 PMCID: PMC4543859 DOI: 10.3389/fnsys.2015.00118] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 08/05/2015] [Indexed: 01/10/2023] Open
Abstract
Thousands of neurons are born each day in the dentate gyrus (DG), but many of these cells die before reaching maturity. Both death and survival of adult-born neurons are regulated by neuronal activity in the DG. The immediate-early gene (IEG) zif268 appears to be an important mediator of these effects, as its expression can be induced by neural activity and knockout of zif268 impairs survival of adult-born neurons (Richardson et al., 1992; Veyrac et al., 2013). Despite the apparent importance of zif268 for adult neurogenesis, its behavior-induced expression has not been fully characterized in adult-born neurons. Here we characterize behavior-evoked expression of zif268 in mature and newborn dentate granule cells (DGCs). We first quantified zif268 expression in doublecortin-positive (DCX+) immature neurons and in the general granule cell population after brief exposure to a novel environment (NE). In the general granule cell population, zif268 expression peaked 1 h after NE exposure and returned to baseline by 8 h post-exposure. However, in the DCX+ cells, zif268 expression was suppressed relative to home cage for at least 8 h post-exposure. We next asked whether suppression of zif268 in DCX+ immature cells occurs in other behavioral paradigms that recruit the hippocampus. Exposure to Morris water maze (MWM) training, an enriched environment, or a NE caused approximately equal suppression of zif268 expression in DCX+ cells and approximately equal activation of zif268 expression among the general granule cell population. The same behavioral procedures activated zif268 expression in 6-week-old BrdU-labeled adult-born neurons, indicating that zif268 suppression is specific to immature neurons. Finally, we asked whether zif268 suppression varied as a function of age within the DCX+ population, which ranges in age from 0 to approximately 4 weeks. NE exposure had no significant effect on zif268 expression in 2- or 4-week-old BrdU-labeled neurons, but it significantly suppressed zif268 expression in 3-week-old neurons. In summary, behavioral experience transiently activated expression of zif268 in mature granule cells but caused a more long-lasting suppression of zif268 expression in immature, adult-born granule cells. We hypothesize that zif268 suppression inhibits memory-related synaptic plasticity in immature neurons or mediates learning-induced apoptosis of immature adult-born neurons.
Collapse
Affiliation(s)
- Kylie A Huckleberry
- Department of Neuroscience, Center for Learning and Memory, University of Texas at Austin Austin, TX, USA
| | - Gary A Kane
- Department of Neuroscience, Center for Learning and Memory, University of Texas at Austin Austin, TX, USA
| | - Rita J Mathis
- Department of Neuroscience, Center for Learning and Memory, University of Texas at Austin Austin, TX, USA
| | - Sarah G Cook
- Department of Neuroscience, Center for Learning and Memory, University of Texas at Austin Austin, TX, USA
| | - Jonathan E Clutton
- Department of Neuroscience, Center for Learning and Memory, University of Texas at Austin Austin, TX, USA
| | - Michael R Drew
- Department of Neuroscience, Center for Learning and Memory, University of Texas at Austin Austin, TX, USA
| |
Collapse
|
21
|
Lee Y, Lee YW, Gao Q, Lee Y, Lee HE, Ryu JH. Exogenous insulin-like growth factor 2 administration enhances memory consolidation and persistence in a time-dependent manner. Brain Res 2015; 1622:466-73. [PMID: 26168901 DOI: 10.1016/j.brainres.2015.07.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 06/15/2015] [Accepted: 07/03/2015] [Indexed: 10/23/2022]
Abstract
Memory consolidation is an important process for the formation of long-term memory. We have previously reported that mature brain-derived neurotrophic factor enhances memory consolidation within 9h after initial learning. Recent studies suggest that insulin-like growth factor 2 (IGF2) significantly enhances memory consolidation and prevents forgetting. Thus, we hypothesized that IGF2 exerts its activity on cognitive performance in a time-dependent manner as observed in our previous study. In the one-trial step-through inhibitory avoidance task, we demonstrate that a bilateral injection of IGF2 into the dorsal hippocampus 6 or 9 h after training significantly enhanced the step-through latencies compared with the vehicle-treated controls in the retention trial, which was conducted 24 h after the acquisition trial. However, 12h post-training, IGF2 injection did not increase the step-through latencies. Intriguingly, in the retention trial at 21 days after the training, hippocampal IGF2 injection 6, 9 or 12 h after the acquisition trial significantly increased the step-through latencies compared with the vehicle-treated controls. IGF2 administration at 9 h and 12 h after the acquisition trial significantly increased discrimination index and exploration time on the novel-located object in the test trial at 24 h and 21 days, respectively, after the acquisition trial in the novel location recognition task. In addition, IGF2-induced an increase in the step-through latencies in the retention trial 24 h or 21 days, respectively, after the initial learning was completely abolished by co-injected anti-IGF2 receptor antibody. These results suggest that IGF2 enhances memory consolidation within 9h after initial learning, and increased IGF2 within the 12 h after the acquisition trial, which represents a delayed consolidation phase, is also critical for memory persistence.
Collapse
Affiliation(s)
- Younghwan Lee
- Department of Life and Nanopharmaceutical Science, Kyung Hee University, Seoul 130-701, Republic of Korea; Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, Seoul 130-701, Republic of Korea
| | - Young Woo Lee
- Department of Life and Nanopharmaceutical Science, Kyung Hee University, Seoul 130-701, Republic of Korea; Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, Seoul 130-701, Republic of Korea
| | - Qingtao Gao
- Department of Life and Nanopharmaceutical Science, Kyung Hee University, Seoul 130-701, Republic of Korea; Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, Seoul 130-701, Republic of Korea
| | - Younghwa Lee
- Department of Life and Nanopharmaceutical Science, Kyung Hee University, Seoul 130-701, Republic of Korea; Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, Seoul 130-701, Republic of Korea
| | - Hyung Eun Lee
- Department of Life and Nanopharmaceutical Science, Kyung Hee University, Seoul 130-701, Republic of Korea; Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, Seoul 130-701, Republic of Korea
| | - Jong Hoon Ryu
- Department of Life and Nanopharmaceutical Science, Kyung Hee University, Seoul 130-701, Republic of Korea; Department of Oriental Pharmaceutical Science, College of Pharmacy, Kyung Hee University, Seoul 130-701, Republic of Korea; Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, Seoul 130-701, Republic of Korea.
| |
Collapse
|
22
|
Expression of early growth response 1 affects miR-106a/signal transducer and activator of transcription 3 regulating cognitive impairment in ovariectomized mice. Menopause 2015; 21:1143-50. [PMID: 24686449 DOI: 10.1097/gme.0000000000000234] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
OBJECTIVE This study aims to investigate the effects of early growth response 1 (Egr1) on miR-106a/signal transducer and activator of transcription 3 (STAT3) regulating cognitive impairment in an ovariectomy model. METHODS Using the Morris water maze test, we assessed escape latency and time spent in a quadrant among mice at 6, 8, and 12 weeks after ovariectomy and their age-matched controls (n = 15 each group). Egr1, miR-106a, and STAT3 messenger RNA expression (n = 7) in the hippocampus and cortex of mice at 6, 8, and 12 weeks after ovariectomy was detected by quantitative real-time polymerase chain reaction, whereas Egr1, phospho-STAT3 (p-STAT3), and STAT3 protein expression (n = 8) was evaluated by Western blot analysis. Moreover, alterations in miR-106a and STAT3 expression were investigated in neuroblastoma (SH-SY5Y) cells transfected with a human Egr1 interference fragment (si-Egr1) or an Egr1-overexpressing plasmid (GV141-Egr1), respectively. RESULTS Escape latency was significantly increased and time spent in a platform quadrant was reduced in mice at 12 weeks after ovariectomy compared with age-matched controls. Egr1 and miR-106a expression was obviously increased in the hippocampus and cortex at 12 weeks after ovariectomy, whereas STAT3 levels were decreased compared with 12-week controls. After SH-SY5Y cell transfection with the si-Egr1 fragment, miR-106a levels decreased and STAT3/p-STAT3 levels increased, whereas cotransfection of the miR-106a mimic caused a significant decrease in STAT3 levels. MiR-106a messenger RNA expression was significantly increased and STAT3/p-STAT3 protein levels were decreased by Egr1 overexpression, whereas simultaneous transfection with the miR-106a inhibitor inhibited alterations in STAT3 levels. CONCLUSIONS This study suggests that Egr1 decreases STAT3 expression via miR-106a in ovariectomized mice with cognitive impairment, indicating that Egr1 represents a potential target for therapeutic intervention in postmenopausal cognitive decline.
Collapse
|
23
|
Walters BJ, Zovkic IB. Building up and knocking down: an emerging role for epigenetics and proteasomal degradation in systems consolidation. Neuroscience 2015; 300:39-52. [PMID: 25967264 DOI: 10.1016/j.neuroscience.2015.05.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 04/18/2015] [Accepted: 05/03/2015] [Indexed: 01/30/2023]
Abstract
Memory formation is a protracted process in which recently acquired events are consolidated to produce stable and specific associations. Initially, newly acquired information undergoes cellular consolidation in the hippocampus, which transiently supports the storage of recently acquired memories. In contrast, remote, or "old" memories are maintained in the cortex and show almost complete independence from the hippocampus. Memories are transferred from the hippocampus to the cortex through a process termed systems consolidation. Emerging evidence suggests that recurrent activation, or "training" of the cortex by the hippocampus is vital to systems consolidation. This process involves prolonged waves of memory-related gene activity in the hippocampus and cortex long after the learning event has terminated. Indeed, molecular events occurring within hours and days of fear conditioning are essential for stabilizing and eventually transitioning the memory to the cortex. It is increasingly evident that molecular mechanisms that exhibit a capacity for prolonged activation may underlie systems consolidation. Processes that have the capacity to control protein abundance over long time scales, such as epigenetic modifications, are prime candidates for the molecular mechanism of systems consolidation. Indeed, recent work has established two types of epigenetic modifications as integral for systems consolidation. First, localized nucleosomal histone variant exchange and histone modifications are integral for early stages of systems consolidation, whereas DNA methylation appears to be utilized to form stable marks that support memory maintenance. Since systems consolidation also requires discrete and time-sensitive changes in protein abundance, additional mechanisms, such as protein degradation, need also be considered, although their role in systems consolidation has yet to be investigated. Here, we discuss the role of molecular mechanisms in systems consolidation and their implications for understanding how memories persist over time.
Collapse
Affiliation(s)
- B J Walters
- The Hospital for Sick Children, Department of Neuroscience and Mental Health, Toronto, ON, Canada
| | - I B Zovkic
- University of Toronto Mississauga, Department of Psychology, Mississauga, ON, Canada.
| |
Collapse
|
24
|
Abstract
Histone variant exchange is a novel epigenetic regulator of cognition. We speculate that H2A.Z, a variant of canonical histone H2A, exerts unique effects on transcription during distinct stages of memory formation, ultimately acting to maintain memory of previous transcriptional states and poise genes for re-activation. Hippocampus-dependent memory formation is initiated by transient expression of memory-related genes, which support the storage of recently acquired memories. Soon after, memories undergo systems consolidation, which transfers memories from the hippocampus to the cortex for long-term storage, and requires ongoing re-activation of memory-related genes. We speculate that learning-induced H2A.Z eviction from nucleosomes initially contributes to stimulus-induced transcriptional induction needed for the initial process of memory consolidation. During systems consolidation, we speculate that delayed incorporation of H2A.Z into nucleosomes of memory-related genes in the cortex is needed to poise genes for rapid re-activation, thus supporting the long-term process of memory stabilization.
Collapse
Affiliation(s)
- Iva B Zovkic
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Brandon J Walters
- Department of Neuroscience and Mental Health, The Hospital for Sick Children, Toronto, ON, Canada
| |
Collapse
|
25
|
Nuclear factor kappa B-dependent Zif268 expression in hippocampus is required for recognition memory in mice. Neurobiol Learn Mem 2015; 119:10-7. [DOI: 10.1016/j.nlm.2014.12.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 12/23/2014] [Accepted: 12/30/2014] [Indexed: 12/28/2022]
|
26
|
Effects of L-theanine on posttraumatic stress disorder induced changes in rat brain gene expression. ScientificWorldJournal 2014; 2014:419032. [PMID: 25165739 PMCID: PMC4137547 DOI: 10.1155/2014/419032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Revised: 04/11/2014] [Accepted: 05/13/2014] [Indexed: 01/02/2023] Open
Abstract
Posttraumatic stress disorder (PTSD) is characterized by the occurrence of a traumatic event that is beyond the normal range of human experience. The future of PTSD treatment may specifically target the molecular mechanisms of PTSD. In the US, approximately 20% of adults report taking herbal products to treat medical illnesses. L-theanine is the amino acid in green tea primarily responsible for relaxation effects. No studies have evaluated the potential therapeutic properties of herbal medications on gene expression in PTSD. We evaluated gene expression in PTSD-induced changes in the amygdala and hippocampus of Sprague-Dawley rats. The rats were assigned to PTSD-stressed and nonstressed groups that received either saline, midazolam, L-theanine, or L-theanine + midazolam. Amygdala and hippocampus tissue samples were analyzed for changes in gene expression. One-way ANOVA was used to detect significant difference between groups in the amygdala and hippocampus. Of 88 genes examined, 17 had a large effect size greater than 0.138. Of these, 3 genes in the hippocampus and 5 genes in the amygdala were considered significant (P < 0.05) between the groups. RT-PCR analysis revealed significant changes between groups in several genes implicated in a variety of disorders ranging from PTSD, anxiety, mood disorders, and substance dependence.
Collapse
|
27
|
Lynch G, Cox CD, Gall CM. Pharmacological enhancement of memory or cognition in normal subjects. Front Syst Neurosci 2014; 8:90. [PMID: 24904313 PMCID: PMC4033242 DOI: 10.3389/fnsys.2014.00090] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 04/30/2014] [Indexed: 12/14/2022] Open
Abstract
The possibility of expanding memory or cognitive capabilities above the levels in high functioning individuals is a topic of intense discussion among scientists and in society at large. The majority of animal studies use behavioral endpoint measures; this has produced valuable information but limited predictability for human outcomes. Accordingly, several groups are pursuing a complementary strategy with treatments targeting synaptic events associated with memory encoding or forebrain network operations. Transcription and translation figure prominently in substrate work directed at enhancement. Notably, the question of why new proteins would be needed for a now-forming memory given that learning-driven synthesis presumably occurred throughout the immediate past has been largely ignored. Despite this conceptual problem, and some controversy, recent studies have reinvigorated the idea that selective gene manipulation is a plausible route to enhancement. Efforts to improve memory by facilitating synaptic encoding of information have also progressed, in part due of breakthroughs on mechanisms that stabilize learning-related, long-term potentiation (LTP). These advances point to a reductionistic hypothesis for a diversity of experimental results on enhancement, and identify under-explored possibilities. Cognitive enhancement remains an elusive goal, in part due to the difficulty of defining the target. The popular view of cognition as a collection of definable computations seems to miss the fluid, integrative process experienced by high functioning individuals. The neurobiological approach obviates these psychological issues to directly test the consequences of improving throughput in networks underlying higher order behaviors. The few relevant studies testing drugs that selectively promote excitatory transmission indicate that it is possible to expand cortical networks engaged by complex tasks and that this is accompanied by capabilities not found in normal animals.
Collapse
Affiliation(s)
- Gary Lynch
- Department of Psychiatry and Human Behavior, University of California Irvine, CA, USA ; Department of Anatomy and Neurobiology, University of California Irvine, CA, USA
| | - Conor D Cox
- Department of Anatomy and Neurobiology, University of California Irvine, CA, USA
| | - Christine M Gall
- Department of Anatomy and Neurobiology, University of California Irvine, CA, USA
| |
Collapse
|
28
|
Shin H, Kwon S, Song H, Lim HJ. The transcription factor Egr3 is a putative component of the microtubule organizing center in mouse oocytes. PLoS One 2014; 9:e94708. [PMID: 24722338 PMCID: PMC3983223 DOI: 10.1371/journal.pone.0094708] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Accepted: 03/17/2014] [Indexed: 11/19/2022] Open
Abstract
The early growth response (Egr) family of zinc finger transcription factors consists of 4 members. During an investigation of Egr factor localization in mouse ovaries, we noted that Egr3 exhibits a subcellular localization that overlaps with the meiotic spindle in oocytes. Using Egr3-specific antibodies, we establish that Egr3 co-localizes with the spindle and cytosolic microtubule organizing centers (MTOCs) in oocytes during meiotic maturation. Notably, the Egr3 protein appears to accumulate around γ-tubulin in MTOCs. Nocodazole treatment, which induces microtubule depolymerization, resulted in the disruption of spindle formation and Egr3 localization, suggesting that Egr3 localization is dependent on the correct configuration of the spindle. Shortly after warming of vitrified oocytes, growing arrays of microtubules were observed near large clusters of Egr3. An in vitro microtubule interaction assay showed that Egr3 does not directly interact with polymerized microtubules. Egr3 localization on the spindle was sustained in early preimplantation mouse embryos, but this pattern did not persist until the blastocyst stage. Collectively, our result shows for the first time that the Egr3 a transcription factor may play a novel non-transcriptional function during microtubule organization in mouse oocytes.
Collapse
Affiliation(s)
- Hyejin Shin
- Department of Biomedical Science & Technology, Institute of Biomedical Science & Technology, Konkuk University, Seoul, Korea
| | - Sojung Kwon
- Department of Biomedical Science & Technology, Institute of Biomedical Science & Technology, Konkuk University, Seoul, Korea
| | - Haengseok Song
- Department of Biomedical Science, College of Life Science, CHA University, Seoul, Korea
| | - Hyunjung Jade Lim
- Department of Biomedical Science & Technology, Institute of Biomedical Science & Technology, Konkuk University, Seoul, Korea
- * E-mail:
| |
Collapse
|
29
|
Asok A, Schreiber WB, Jablonski SA, Rosen JB, Stanton ME. Egr-1 increases in the prefrontal cortex following training in the context preexposure facilitation effect (CPFE) paradigm. Neurobiol Learn Mem 2013; 106:145-53. [PMID: 23973447 DOI: 10.1016/j.nlm.2013.08.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Revised: 08/09/2013] [Accepted: 08/16/2013] [Indexed: 01/09/2023]
Abstract
The context pre-exposure facilitation effect (CPFE) is a modified form of standard contextual fear conditioning that dissociates learning about the context during a preexposure phase from learning the context-shock association during an immediate shock training phase conducted on separate days. Fear conditioning in the CPFE is an associative process in which only animals that are preexposed to the same context they are later given an immediate shock in demonstrate freezing when tested for conditioned fear memory. Previous research has shown that the hippocampus and amygdala are necessary for different phases of the CPFE, but whether other brain regions are also involved is unknown. The present study examined expression of the immediate-early gene early growth response gene 1 (Egr-1; also called Zif268, Ngfi-a, Krox-24) in the dorsal hippocampus, lateral nucleus of the amygdala, retrosplenial cortex, and several prefrontal cortex regions (infralimbic and prelimbic medial prefrontal cortex, anterior cingulate, and orbitofrontal cortex) following each phase of the CPFE in juvenile rats. Animals preexposed to the conditioning context displayed fear conditioned freezing during a retention test whereas rats preexposed to an alternate context did not. Following context preexposure, Egr-1 mRNA was elevated in context and alternate context exposed animals compared to home-cage control rats in almost all regions analyzed. Following the context-shock training phase, fear conditioned rats displayed significantly more Egr-1 mRNA expression in the infralimbic, prelimbic, and orbitofrontal cortices compared to the alternate context preexposed control rats. These differences in Egr-1 expression were not found in amygdala between the preexposed context and alternate context rats. No sex differences were observed following preexposure or training in any regions analyzed. The findings suggest that increased expression of Egr-1 within the prefrontal cortex is associated with contextual fear conditioning in the CPFE paradigm.
Collapse
Affiliation(s)
- Arun Asok
- Department of Psychology, University of Delaware, Newark, DE 19716, USA
| | | | | | | | | |
Collapse
|
30
|
Molecular signatures and mechanisms of long-lasting memory consolidation and storage. Neurobiol Learn Mem 2013; 106:40-7. [PMID: 23831672 DOI: 10.1016/j.nlm.2013.06.018] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 06/25/2013] [Accepted: 06/26/2013] [Indexed: 12/27/2022]
Abstract
A body of evidence emerged in the last decade regarding late posttraining memory processing. Most of this new information comes from aversively motivated learning tasks that mainly depend on hippocampus, amygdala and insular cortex, and points to the involvement of long-lasting changes in gene expression and protein synthesis in late stages of memory consolidation and storage. Here, we describe recent advances in this field and discuss how recurrent rounds of macromolecular synthesis and its regulation might impact long-term memory storage.
Collapse
|
31
|
Bekinschtein P, Cammarota M, Medina JH. BDNF and memory processing. Neuropharmacology 2013; 76 Pt C:677-83. [PMID: 23688925 DOI: 10.1016/j.neuropharm.2013.04.024] [Citation(s) in RCA: 246] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 03/14/2013] [Accepted: 04/08/2013] [Indexed: 01/19/2023]
Abstract
Brain-derived neurotrophic factor has emerged as one of the most important molecules involved in memory. Its wide role in different types of memories that depend on different structures as well as its involvement in distinct memory stages points at BDNF as one likely target to treat cognitive impairments and anxiety-related memory disorders. However, regulation of BDNF expression is very complex as well as its modes of action. Here we describe the latest research carried out on the function of BDNF in memory to illustrate such complexity. This article is part of the Special Issue entitled 'BDNF Regulation of Synaptic Structure, Function, and Plasticity'.
Collapse
Affiliation(s)
- Pedro Bekinschtein
- Instituto de Biologia Celular y Neurociencias, Facultad de Medicina, UBA, Argentina
| | | | | |
Collapse
|
32
|
Cyriac A, Holmes G, Lass J, Belchenko D, Calin-Jageman RJ, Calin-Jageman IE. An Aplysia Egr homolog is rapidly and persistently regulated by long-term sensitization training. Neurobiol Learn Mem 2013; 102:43-51. [PMID: 23567107 DOI: 10.1016/j.nlm.2013.03.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 03/21/2013] [Accepted: 03/24/2013] [Indexed: 02/03/2023]
Abstract
The Egr family of transcription factors plays a key role in long-term plasticity and memory in a number of vertebrate species. Here we identify and characterize ApEgr (GenBank: KC608221), an Egr homolog in the marine mollusk Aplysia californica. ApEgr codes for a predicted 593-amino acid protein with the highly conserved trio of zinc-fingered domains in the C-terminus that characterizes the Egr family of transcription factors. Promoter analysis shows that the ApEgr protein selectively recognizes the GSG motif recognized by vertebrate Egrs. Like mammalian Egrs, ApEgr is constitutively expressed in a range of tissues, including the CNS. Moreover, expression of ApEgr is bi-directionally regulated by changes in neural activity. Of most interest, the association between ApEgr function and memory may be conserved in Aplysia, as we observe rapid and long-lasting up-regulation of expression after long-term sensitization training. Taken together, our results suggest that Egrs may have memory functions that are conserved from mammals to mollusks.
Collapse
Affiliation(s)
- Ashly Cyriac
- Neuroscience Program, Dominican University, 7900 West Division Street, River Forest, IL 60305, United States
| | | | | | | | | | | |
Collapse
|
33
|
Yang C, Liu JF, Chai BS, Fang Q, Chai N, Zhao LY, Xue YX, Luo YX, Jian M, Han Y, Shi HS, Lu L, Wu P, Wang JS. Stress within a restricted time window selectively affects the persistence of long-term memory. PLoS One 2013; 8:e59075. [PMID: 23544051 PMCID: PMC3609809 DOI: 10.1371/journal.pone.0059075] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 02/11/2013] [Indexed: 12/02/2022] Open
Abstract
The effects of stress on emotional memory are distinct and depend on the stages of memory. Memory undergoes consolidation and reconsolidation after acquisition and retrieval, respectively. Stress facilitates the consolidation but disrupts the reconsolidation of emotional memory. Previous research on the effects of stress on memory have focused on long-term memory (LTM) formation (tested 24 h later), but the effects of stress on the persistence of LTM (tested at least 1 week later) are unclear. Recent findings indicated that the persistence of LTM requires late-phase protein synthesis in the dorsal hippocampus. The present study investigated the effect of stress (i.e., cold water stress) during the late phase after the acquisition and retrieval of contextual fear memory in rats. We found that stress and corticosterone administration during the late phase (12 h) after acquisition, referred to as late consolidation, selectively enhanced the persistence of LTM, whereas stress during the late phase (12 h) after retrieval, referred to as late reconsolidation, selectively disrupted the restabilized persistence of LTM. Moreover, the effects of stress on the persistence of LTM were blocked by the corticosterone synthesis inhibitor metyrapone, which was administered before stress, suggesting that the glucocorticoid system is involved in the effects of stress on the persistence of LTM. We conclude that stress within a restricted time window after acquisition or retrieval selectively affects the persistence of LTM and depends on the glucocorticoid system.
Collapse
Affiliation(s)
- Chang Yang
- Affiliated Hospital and School of Pharmacy of Guiyang Medical University, Guiyang, China
| | - Jian-Feng Liu
- National Institute on Drug Dependence, Peking University, Beijing, China
| | - Bai-Sheng Chai
- Affiliated Hospital and School of Pharmacy of Guiyang Medical University, Guiyang, China
| | - Qin Fang
- Affiliated Hospital and School of Pharmacy of Guiyang Medical University, Guiyang, China
| | - Ning Chai
- Institute of Mental Health, Hebei Medical University, Shijiazhuang, China
- Hebei Brain Ageing and Cognitive Neuroscience Laboratory, Hebei Medical University, Shijiazhuang, China
| | - Li-Yan Zhao
- National Institute on Drug Dependence, Peking University, Beijing, China
| | - Yan-Xue Xue
- National Institute on Drug Dependence, Peking University, Beijing, China
| | - Yi-Xiao Luo
- National Institute on Drug Dependence, Peking University, Beijing, China
| | - Min Jian
- National Institute on Drug Dependence, Peking University, Beijing, China
| | - Ying Han
- National Institute on Drug Dependence, Peking University, Beijing, China
| | - Hai-Shui Shi
- Department of Biochemistry and Molecular Biology, Basic Medical College, Hebei Medical University, Shijiazhuang, China
| | - Lin Lu
- National Institute on Drug Dependence, Peking University, Beijing, China
| | - Ping Wu
- National Institute on Drug Dependence, Peking University, Beijing, China
- * E-mail: (PW); (JSW)
| | - Ji-Shi Wang
- Affiliated Hospital and School of Pharmacy of Guiyang Medical University, Guiyang, China
- * E-mail: (PW); (JSW)
| |
Collapse
|