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Zhang H, Rodriguez-Hernandez LD, D'Souza AJ, He D, Zain M, Fung SW, Bennett LA, Bonin RP. Nociceptor activity induces nonionotropic NMDA receptor signaling to enable spinal reconsolidation and reverse pathological pain. SCIENCE ADVANCES 2023; 9:eadg2819. [PMID: 37205760 DOI: 10.1126/sciadv.adg2819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 04/17/2023] [Indexed: 05/21/2023]
Abstract
Chronic, pathological pain is a highly debilitating condition that can arise and be maintained through central sensitization. Central sensitization shares mechanistic and phenotypic parallels with memory formation. In a sensory model of memory reconsolidation, plastic changes underlying pain hypersensitivity can be dynamically regulated and reversed following the reactivation of sensitized sensory pathways. However, the mechanisms by which synaptic reactivation induces destabilization of the spinal "pain engram" are unclear. We identified nonionotropic N-methyl-d-aspartate receptor (NI-NMDAR) signaling as necessary and sufficient for the reactive destabilization of dorsal horn long-term potentiation and the reversal of mechanical sensitization associated with central sensitization. NI-NMDAR signaling engaged directly or through the reactivation of sensitized sensory networks was associated with the degradation of excitatory postsynaptic proteins. Our findings identify NI-NMDAR signaling as a putative synaptic mechanism by which engrams are destabilized in reconsolidation and as a potential means of treating underlying causes of chronic pain.
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Affiliation(s)
- Hantao Zhang
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Luis D Rodriguez-Hernandez
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Abigail J D'Souza
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - David He
- Department of Anesthesia, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Maham Zain
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Samuel W Fung
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Laura A Bennett
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Robert P Bonin
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
- University of Toronto Centre for the Study of Pain, University of Toronto, Toronto, Ontario, Canada
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2
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Li M, Wang L, Guo S, Huang N, Ai H. Cordycepin buffers anisomycin-induced fear memory deficit by restoring hippocampal BDNF. Biochem Biophys Res Commun 2023; 665:118-123. [PMID: 37156049 DOI: 10.1016/j.bbrc.2023.05.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 04/23/2023] [Accepted: 05/02/2023] [Indexed: 05/10/2023]
Abstract
The process of memory consolidation involves the synthesis of new proteins, and interfering with protein synthesis through anisomycin can impair memory. Memory deficits due to aging and sleep disorders may also result from a reduction in protein synthesis. Rescuing memory deficits caused by protein synthesis deficiency is therefore an important issue that needs to be addressed. Our study focused on the effects of cordycepin on fear memory deficits induced by anisomycin using contextual fear conditioning. We observed that cordycepin was able to attenuate these deficits and restore BDNF levels in the hippocampus. The behavioral effects of cordycepin were dependent on the BDNF/TrkB pathway, as demonstrated by the use of ANA-12. Cordycepin had no significant impact on locomotor activity, anxiety or fear memory. Our findings provide the first evidence that cordycepin can prevent anisomycin-induced memory deficits by regulating BDNF expression in the hippocampus.
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Affiliation(s)
- Minghao Li
- School of Basic Medical Sciences and Forensic Medicine, Hangzhou Medical College, Hangzhou, Zhejiang, China
| | - Li Wang
- School of Basic Medical Sciences and Forensic Medicine, Hangzhou Medical College, Hangzhou, Zhejiang, China
| | - Siyuan Guo
- School of Basic Medical Sciences and Forensic Medicine, Hangzhou Medical College, Hangzhou, Zhejiang, China
| | - Nan Huang
- School of Basic Medical Sciences and Forensic Medicine, Hangzhou Medical College, Hangzhou, Zhejiang, China
| | - Heng Ai
- School of Basic Medical Sciences and Forensic Medicine, Hangzhou Medical College, Hangzhou, Zhejiang, China.
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3
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Shi X, von Weltin E, Fitzsimmons E, Do C, Caban Rivera C, Chen C, Liu-Chen LY, Unterwald EM. Reactivation of cocaine contextual memory engages mechanistic target of rapamycin/S6 kinase 1 signaling. Front Pharmacol 2022; 13:976932. [PMID: 36238569 PMCID: PMC9552424 DOI: 10.3389/fphar.2022.976932] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 08/25/2022] [Indexed: 11/25/2022] Open
Abstract
Mechanistic target of rapamycin (mTOR) C1 and its downstream effectors have been implicated in synaptic plasticity and memory. Our prior work demonstrated that reactivation of cocaine memory engages a signaling pathway consisting of Akt, glycogen synthase kinase-3β (GSK3β), and mTORC1. The present study sought to identify other components of mTORC1 signaling involved in the reconsolidation of cocaine contextual memory, including eukaryotic translation initiation factor 4E (eIF4E)-eIF4G interactions, p70 S6 kinase polypeptide 1 (p70S6K, S6K1) activity, and activity-regulated cytoskeleton (Arc) expression. Cocaine contextual memory was established in adult CD-1 mice using conditioned place preference. After cocaine place preference was established, mice were briefly re-exposed to the cocaine-paired context to reactivate the cocaine memory and brains examined. Western blot analysis showed that phosphorylation of the mTORC1 target, p70S6K, in nucleus accumbens and hippocampus was enhanced 60 min following reactivation of cocaine memories. Inhibition of mTORC1 with systemic administration of rapamycin or inhibition of p70S6K with systemic PF-4708671 after reactivation of cocaine contextual memory abolished the established cocaine place preference. Immunoprecipitation assays showed that reactivation of cocaine memory did not affect eIF4E-eIF4G interactions in nucleus accumbens or hippocampus. Levels of Arc mRNA were significantly elevated 60 and 120 min after cocaine memory reactivation and returned to baseline 24 h later. These findings demonstrate that mTORC1 and p70S6K are required for reconsolidation of cocaine contextual memory.
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Affiliation(s)
- Xiangdang Shi
- Center for Substance Abuse Research and Department of Neural Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States
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4
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Magwai T, Shangase KB, Oginga FO, Chiliza B, Mpofana T, Xulu KR. DNA Methylation and Schizophrenia: Current Literature and Future Perspective. Cells 2021; 10:2890. [PMID: 34831111 PMCID: PMC8616184 DOI: 10.3390/cells10112890] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/09/2021] [Accepted: 10/12/2021] [Indexed: 12/12/2022] Open
Abstract
Schizophrenia is a neuropsychiatric disorder characterized by dissociation of thoughts, idea, identity, and emotions. It has no central pathophysiological mechanism and precise diagnostic markers. Despite its high heritability, there are also environmental factors implicated in the development of schizophrenia. Epigenetic factors are thought to mediate the effects of environmental factors in the development of the disorder. Epigenetic modifications like DNA methylation are a risk factor for schizophrenia. Targeted gene approach studies attempted to find candidate gene methylation, but the results are contradictory. Genome-wide methylation studies are insufficient in literature and the available data do not cover different populations like the African populations. The current genome-wide studies have limitations related to the sample and methods used. Studies are required to control for these limitations. Integration of DNA methylation, gene expression, and their effects are important in the understanding of the development of schizophrenia and search for biomarkers. There are currently no precise and functional biomarkers for the disorder. Several epigenetic markers have been reported to be common in functional and peripheral tissue. This makes the peripheral tissue epigenetic changes a surrogate of functional tissue, suggesting common epigenetic alteration can be used as biomarkers of schizophrenia in peripheral tissue.
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Affiliation(s)
- Thabo Magwai
- Department of Physiology, School of Laboratory Medicine and Medical Sciences, University of Kwa-Zulu Natal, Durban 4001, South Africa; (K.B.S.); (F.O.O.); (T.M.)
- National Health Laboratory Service, Department of Chemical Pathology, University of Kwa-Zulu Natal, Durban 4085, South Africa
| | - Khanyiso Bright Shangase
- Department of Physiology, School of Laboratory Medicine and Medical Sciences, University of Kwa-Zulu Natal, Durban 4001, South Africa; (K.B.S.); (F.O.O.); (T.M.)
| | - Fredrick Otieno Oginga
- Department of Physiology, School of Laboratory Medicine and Medical Sciences, University of Kwa-Zulu Natal, Durban 4001, South Africa; (K.B.S.); (F.O.O.); (T.M.)
| | - Bonginkosi Chiliza
- Department of Psychiatry, Nelson R Mandela School of Medicine, University of Kwa-Zulu Natal, Durban 4001, South Africa;
| | - Thabisile Mpofana
- Department of Physiology, School of Laboratory Medicine and Medical Sciences, University of Kwa-Zulu Natal, Durban 4001, South Africa; (K.B.S.); (F.O.O.); (T.M.)
| | - Khethelo Richman Xulu
- Department of Physiology, School of Laboratory Medicine and Medical Sciences, University of Kwa-Zulu Natal, Durban 4001, South Africa; (K.B.S.); (F.O.O.); (T.M.)
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l-Lactate: Food for Thoughts, Memory and Behavior. Metabolites 2021; 11:metabo11080548. [PMID: 34436491 PMCID: PMC8398236 DOI: 10.3390/metabo11080548] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/02/2021] [Accepted: 08/11/2021] [Indexed: 01/18/2023] Open
Abstract
More and more evidence shows how brain energy metabolism is the linkage between physiological and morphological synaptic plasticity and memory consolidation. Different types of memory are associated with differential inputs, each with specific inputs that are upstream diverse molecular cascades depending on the receptor activity. No matter how heterogeneous the response is, energy availability represents the lowest common denominator since all these mechanisms are energy consuming and the brain networks adapt their performance accordingly. Astrocytes exert a primary role in this sense by acting as an energy buffer; glycogen granules, a mechanism to store glucose, are redistributed at glance and conveyed to neurons via the Astrocyte–Neuron Lactate Shuttle (ANLS). Here, we review how different types of memory relate to the mechanisms of energy delivery in the brain.
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Sheikholeslami MA, Ghafghazi S, Pouriran R, Mortazavi SE, Parvardeh S. Attenuating effect of paroxetine on memory impairment following cerebral ischemia-reperfusion injury in rat: The involvement of BDNF and antioxidant capacity. Eur J Pharmacol 2021; 893:173821. [PMID: 33347827 DOI: 10.1016/j.ejphar.2020.173821] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 12/11/2020] [Accepted: 12/16/2020] [Indexed: 10/22/2022]
Abstract
Memory impairments are frequently reported in patients suffering from brain ischemic diseases. Oxidative/nitrosative stress, synaptic plasticity, and brain-derived neurotrophic factor (BDNF) are involved in the physiopathology of brain ischemia-induced memory disorders. In the present study, the effect of paroxetine as an efficacious antidepressant medication with antioxidant properties was evaluated on passive avoidance memory deficit following cerebral ischemia in rats. Transient occlusion of common carotid arteries was applied to induce ischemia-reperfusion injury in male Wistar rats. Paroxetine (5, 10, 20 mg/kg) was administered intraperitoneally once daily before (for 3 days) or after (for 7 days) the induction of ischemia. A week after ischemia-reperfusion injury, passive avoidance memory, long-term potentiation (LTP), BDNF levels, total antioxidant capacity, the activity of antioxidant enzymes (including catalase, glutathione peroxidase, and superoxide dismutase), the concentration of malondialdehyde (MDA), and nitric oxide (NO) were investigated in the hippocampus. In the passive avoidance test, paroxetine significantly increased the step-through latency and decreased the time spent in the dark compartment. This affirmative function of paroxetine on the passive avoidance memory was accompanied by the improvement of hippocampal LTP and an obvious augmentation in the BDNF contents. Besides, paroxetine caused a significant rise in the total antioxidant capacity and antioxidant enzyme activity; while decreased the hippocampal levels of NO and MDA. It was ultimately attained that paroxetine attenuates cerebral ischemia-induced passive avoidance memory dysfunction in rats by the enhancement of hippocampal synaptic plasticity and BDNF content together with the suppression of oxidative/nitrosative stress.
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Affiliation(s)
| | - Shiva Ghafghazi
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ramin Pouriran
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Seyed Erfan Mortazavi
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Siavash Parvardeh
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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7
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Walsh K, Iskandar G, Kamboj SK, Das RK. An assessment of rapamycin for weakening binge-eating memories via reconsolidation: a pre-registered, double-blind randomised placebo-controlled experimental study. Psychol Med 2021; 51:158-167. [PMID: 31736460 DOI: 10.1017/s003329171900312x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Maladaptive learning linking environmental food cues to high-palatability food reward plays a central role in overconsumption in obesity and binge eating disorders. The process of memory reconsolidation offers a mechanism to weaken such learning, potentially ameliorating over-eating behaviour. Here we investigated whether putatively interfering with synaptic plasticity using the mammalian target of rapamycin (mTOR) inhibitor, rapamycin, could weaken retrieved chocolate reward memories through blockade of reconsolidation. METHODS Seventy five healthy volunteers with a tendency to binge eat chocolate were randomised to retrieve chocolate reward memory under 10 mg rapamycin (RET + RAP, active condition), or placebo (RET + PBO), or they received 10 mg rapamycin without subsequent retrieval (NO RET + RAP). Indices of chocolate reward memory strength were assessed one week pre and post manipulation and at one month follow-up. RESULTS Contrary to hypotheses, the RET + RAP group did not show any greater reduction than control groups on indices of motivational salience of chocolate cues, motivation to consume chocolate or liking of chocolate. Mild evidence of improvement in the RET + RAP group was found, but this was limited to reduced chocolate binge episodes and improved healthy food choices. CONCLUSIONS We did not find convincing evidence of comprehensive naturalistic chocolate reward memory reconsolidation blockade by rapamycin. The effects on chocolate bingeing and food choices may warrant further investigation. These limited positive findings may be attributable to insufficient interference with mTOR signalling with 10 mg rapamycin, or failure to destabilise chocolate memories during retrieval.
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Affiliation(s)
- Katie Walsh
- Clinical, Educational and Health Psychology, University College London, Gower Street, London, WC1E 6BT
| | - Georges Iskandar
- University College Hospital and University College Hospital at Westmoreland Street, London, UK
| | - Sunjeev K Kamboj
- Clinical, Educational and Health Psychology, University College London, Gower Street, London, WC1E 6BT
| | - Ravi K Das
- Clinical, Educational and Health Psychology, University College London, Gower Street, London, WC1E 6BT
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8
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Contextual experience modifies functional connectome indices of topological strength and efficiency. Sci Rep 2020; 10:19843. [PMID: 33199790 PMCID: PMC7670469 DOI: 10.1038/s41598-020-76935-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 10/27/2020] [Indexed: 11/08/2022] Open
Abstract
Stimuli presented at short temporal delays before functional magnetic resonance imaging (fMRI) can have a robust impact on the organization of synchronous activity in resting state networks. This presents an opportunity to investigate how sensory, affective and cognitive stimuli alter functional connectivity in rodent models. In the present study we assessed the effect on functional connectivity of a familiar contextual stimulus presented 10 min prior to sedation for imaging. A subset of animals were co-presented with an unfamiliar social stimulus in the same environment to further investigate the effect of familiarity on network topology. Rats were imaged at 11.1 T and graph theory analysis was applied to matrices generated from seed-based functional connectivity data sets with 144 brain regions (nodes) and 10,152 pairwise correlations (after excluding 144 diagonal edges). Our results show substantial changes in network topology in response to the familiar (context). Presentation of the familiar context, both in the absence and presence of the social stimulus, strongly reduced network strength, global efficiency, and altered the location of the highest eigenvector centrality nodes from cortex to the hypothalamus. We did not observe changes in modular organization, nodal cartographic assignments, assortative mixing, rich club organization, and network resilience. We propose that experiential factors, perhaps involving associative or episodic memory, can exert a dramatic effect on functional network strength and efficiency when presented at a short temporal delay before imaging.
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9
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Oliveira NCM, Lins ÉM, Massirer KB, Bengtson MH. Translational Control during Mammalian Neocortex Development and Postembryonic Neuronal Function. Semin Cell Dev Biol 2020; 114:36-46. [PMID: 33020045 DOI: 10.1016/j.semcdb.2020.09.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 09/09/2020] [Accepted: 09/09/2020] [Indexed: 12/21/2022]
Abstract
The control of mRNA translation has key roles in the regulation of gene expression and biological processes such as mammalian cellular differentiation and identity. Methodological advances in the last decade have resulted in considerable progress towards understanding how translational control contributes to the regulation of diverse biological phenomena. In this review, we discuss recent findings in the involvement of translational control in the mammalian neocortex development and neuronal biology. We focus on regulatory mechanisms that modulate translational efficiency during neural stem cells self-renewal and differentiation, as well as in neuronal-related processes such as synapse, plasticity, and memory.
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Affiliation(s)
- Natássia Cristina Martins Oliveira
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas - UNICAMP, 13083-862, Campinas, SP, Brazil; Center for Molecular Biology and Genetic Engineering - CBMEG, University of Campinas - UNICAMP, 13083-875, Campinas, SP, Brazil; Center of Medicinal Chemistry - CQMED, Structural Genomics Consortium - SGC, University of Campinas - UNICAMP, 13083-886, Campinas, SP, Brazil
| | - Érico Moreto Lins
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas - UNICAMP, 13083-862, Campinas, SP, Brazil; PhD Program in Genetics and Molecular Biology (PGBM), UNICAMP, Campinas, SP 13083-862, Brazil
| | - Katlin Brauer Massirer
- Center for Molecular Biology and Genetic Engineering - CBMEG, University of Campinas - UNICAMP, 13083-875, Campinas, SP, Brazil; Center of Medicinal Chemistry - CQMED, Structural Genomics Consortium - SGC, University of Campinas - UNICAMP, 13083-886, Campinas, SP, Brazil
| | - Mário Henrique Bengtson
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas - UNICAMP, 13083-862, Campinas, SP, Brazil; Center of Medicinal Chemistry - CQMED, Structural Genomics Consortium - SGC, University of Campinas - UNICAMP, 13083-886, Campinas, SP, Brazil.
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10
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Musaus M, Navabpour S, Jarome TJ. The diversity of linkage-specific polyubiquitin chains and their role in synaptic plasticity and memory formation. Neurobiol Learn Mem 2020; 174:107286. [PMID: 32745599 DOI: 10.1016/j.nlm.2020.107286] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/15/2020] [Accepted: 07/28/2020] [Indexed: 12/12/2022]
Abstract
Over the last 20 years, a number of studies have provided strong support for protein degradation mediated by the ubiquitin-proteasome system in synaptic plasticity and memory formation. In this system, target substrates become covalently modified by the small protein ubiquitin through a series of enzymatic reactions involving hundreds of different ligases. While some substrates will acquire only a single ubiquitin, most will be marked by multiple ubiquitin modifications, which link together at specific lysine sites or the N-terminal methionine on the previous ubiquitin to form a polyubiquitin chain. There are at least eight known linkage-specific polyubiquitin chains a target protein can acquire, many of which are independent of the proteasome, and these chains can be homogenous, mixed, or branched in nature, all of which result in different functional outcomes and fates for the target substrate. However, as the focus has remained on protein degradation, much remains unknown about the role of these diverse ubiquitin chains in the brain, particularly during activity- and learning-dependent synaptic plasticity. Here, we review the different types and functions of ubiquitin chains and summarize evidence suggesting a role for these diverse ubiquitin modifications in synaptic plasticity and memory formation. We conclude by discussing how technological limitations have limited our ability to identify and elucidate the role of different ubiquitin chains in the brain and speculate on the future directions and implications of understanding linkage-specific ubiquitin modifications in activity- and learning-dependent synaptic plasticity.
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Affiliation(s)
- Madeline Musaus
- School of Neuroscience, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Shaghayegh Navabpour
- Fralin Biomedical Research Institute, Translational Biology, Medicine and Health, Virginia Polytechnic Institute and State University, Roanoke, VA, USA
| | - Timothy J Jarome
- School of Neuroscience, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA; Fralin Biomedical Research Institute, Translational Biology, Medicine and Health, Virginia Polytechnic Institute and State University, Roanoke, VA, USA; Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
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11
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Cossenza M, Socodato R, Mejía-García TA, Domith I, Portugal CC, Gladulich LFH, Duarte-Silva AT, Khatri L, Antoine S, Hofmann F, Ziff EB, Paes-de-Carvalho R. Protein synthesis inhibition promotes nitric oxide generation and activation of CGKII-dependent downstream signaling pathways in the retina. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118732. [PMID: 32360667 DOI: 10.1016/j.bbamcr.2020.118732] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 04/15/2020] [Accepted: 04/26/2020] [Indexed: 01/28/2023]
Abstract
Nitric oxide is an important neuromodulator in the CNS, and its production within neurons is modulated by NMDA receptors and requires a fine-tuned availability of L-arginine. We have previously shown that globally inhibiting protein synthesis mobilizes intracellular L-arginine "pools" in retinal neurons, which concomitantly enhances neuronal nitric oxide synthase-mediated nitric oxide production. Activation of NMDA receptors also induces local inhibition of protein synthesis and L-arginine intracellular accumulation through calcium influx and stimulation of eucariotic elongation factor type 2 kinase. We hypothesized that protein synthesis inhibition might also increase intracellular L-arginine availability to induce nitric oxide-dependent activation of downstream signaling pathways. Here we show that nitric oxide produced by inhibiting protein synthesis (using cycloheximide or anisomycin) is readily coupled to AKT activation in a soluble guanylyl cyclase and cGKII-dependent manner. Knockdown of cGKII prevents cycloheximide or anisomycin-induced AKT activation and its nuclear accumulation. Moreover, in retinas from cGKII knockout mice, cycloheximide was unable to enhance AKT phosphorylation. Indeed, cycloheximide also produces an increase of ERK phosphorylation which is abrogated by a nitric oxide synthase inhibitor. In summary, we show that inhibition of protein synthesis is a previously unanticipated driving force for nitric oxide generation and activation of downstream signaling pathways including AKT and ERK in cultured retinal cells. These results may be important for the regulation of synaptic signaling and neuronal development by NMDA receptors as well as for solving conflicting data observed when using protein synthesis inhibitors for studying neuronal survival during development as well in behavior and memory studies.
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Affiliation(s)
- Marcelo Cossenza
- Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil; Department of Physiology and Pharmacology, Biomedical Institute, Fluminense Federal University, Niterói, RJ, Brazil.
| | - Renato Socodato
- Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil; Instituto de Investigação e Inovação em Saúde (i3S) and Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto, Porto, Portugal
| | - Telmo A Mejía-García
- Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil
| | - Ivan Domith
- Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil
| | - Camila C Portugal
- Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil; Instituto de Investigação e Inovação em Saúde (i3S) and Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto, Porto, Portugal
| | - Luis F H Gladulich
- Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil
| | - Aline T Duarte-Silva
- Department of Neurobiology, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil
| | - Latika Khatri
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY, United States
| | - Shannon Antoine
- Graduate Program in Neuroscience & Physiology, New York University School of Medicine, New York, NY, United States
| | - Franz Hofmann
- Institut für Pharmakologie und Toxikologie der TU-München, Munich, Germany
| | - Edward B Ziff
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY, United States
| | - Roberto Paes-de-Carvalho
- Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil; Department of Neurobiology, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil.
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12
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Threat Memory Reminder Under Matrix Metalloproteinase 9 Inhibitor Doxycycline Globally Reduces Subsequent Memory Plasticity. J Neurosci 2019; 39:9424-9434. [PMID: 31615840 PMCID: PMC6867817 DOI: 10.1523/jneurosci.1285-19.2019] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 08/16/2019] [Accepted: 09/11/2019] [Indexed: 11/21/2022] Open
Abstract
Associative memory can be rendered malleable by a reminder. Blocking the ensuing reconsolidation process is suggested as a therapeutic target for unwanted aversive memories. Matrix metalloproteinase-9 (MMP-9) is required for structural synapse remodeling involved in memory consolidation. Inhibiting MMP-9 with doxycycline is suggested to attenuate human threat conditioning. Here, we investigated whether MMP-9 inhibition also interferes with threat memory reconsolidation. Male and female human participants (N = 78) learned the association between two visual conditioned stimuli (CS+) and a 50% chance of an unconditioned nociceptive stimulus (US), and between CS- and the absence of US. On day 7, one CS+ was reminded without reinforcement 3.5 h after ingesting either 200 mg of doxycycline or placebo. On day 14, retention of CS memory was assessed under extinction by fear-potentiated startle. Contrary to our expectations, we observed a greater CS+/CS- difference in participants who were reminded under doxycycline compared with placebo. Participants who were reminded under placebo showed extinction learning during the retention test, which was not observed in the doxycycline group. There was no difference between the reminded and the nonreminded CS+ in either group. In contrast, during relearning after the retention test, the CS+/CS- difference was more pronounced in the placebo group than in the doxycycline group. To summarize, a single dose of doxycycline before threat memory reminder appeared to have no specific impact on reconsolidation, but to globally impair extinction learning, and threat relearning, beyond drug clearance.SIGNIFICANCE STATEMENT Matrix metalloproteinase-9 inhibition appears to attenuate memory consolidation. It could also be a target for blocking reconsolidation. Here, we test this hypothesis in human threat conditioning. We find that doxycycline has no specific impact on a reminded cue, but confers a global reduction in extinction learning and threat learning beyond the clearance of the drug. This may point toward a more long-lasting impact of doxycycline treatment on memory plasticity.
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13
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Kamboj K, Jana S, Sharma SK. Mechanisms of protein kinase C-induced sustained activation of extracellular signal-regulated kinase in the hippocampus. Biochem Biophys Res Commun 2019; 520:453-458. [PMID: 31607483 DOI: 10.1016/j.bbrc.2019.10.046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 10/03/2019] [Indexed: 10/25/2022]
Abstract
Protein Kinase C (PKC) and extracellular signal-regulated kinase (ERK) regulate synaptic plasticity and memory. PKC activation enhances long-term potentiation (LTP) in the hippocampal slices. In addition, activation of PKC by phorbol 12,13-diacetate (PDA) induces ERK activation. However, the mechanisms involved in PDA-induced activation of ERK are not well understood. Using hippocampal slices, we report that PDA induces a sustained activation of ERK. PDA-induced sustained ERK activation critically requires protein synthesis as well as transcription, the cellular processes that play crucial roles in long-lasting LTP and memory. In addition, the mammalian target of rapamycin activity is required for PDA-induced sustained ERK activation. Further, we show that growth factor signalling plays a critical role in PDA-induced sustained ERK activation. These results suggest that sustained ERK activation may have an important role in LTP.
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Affiliation(s)
- Kautuk Kamboj
- National Brain Research Centre, Manesar, 122052, Haryana, India
| | - Subhajit Jana
- National Brain Research Centre, Manesar, 122052, Haryana, India
| | - Shiv K Sharma
- National Brain Research Centre, Manesar, 122052, Haryana, India.
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14
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Nikitin VP, Solntseva SV, Kozyrev SA, Nikitin PV. Proteins or RNA synthesis inhibitors suppressed induction of amnesia developing under impairment of memory reconsolidation by serotonin receptors antagonist. Neurochem Int 2019; 131:104520. [PMID: 31400436 DOI: 10.1016/j.neuint.2019.104520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 08/03/2019] [Accepted: 08/07/2019] [Indexed: 10/26/2022]
Abstract
Studies have shown that retrieval of long-term memory can cause memory reconsolidation, and impaired reconsolidation leads to amnesia development. However, the mechanisms of amnesia induction due to impaired memory reconsolidation remains poorly described. Using experiments involving grape snails trained to conditioned food aversion, we studied the role of translation and transcription processes and the role of serotonin receptors in the mechanisms of amnesia induction. We found that administration of a serotonin receptor antagonist or a protein synthesis inhibitor before the administration of a reminder using a conditioned food stimulus induced amnesia development, whereas injections of mRNA synthesis inhibitor did not affect memory safety. Moreover, combined injections of an antagonist of serotonin receptor and inhibitors of protein or mRNA synthesis before reminder administration completely prevented amnesia development. In addition, inhibitors of protein or mRNA synthesis prevented amnesia development 3 h but not 9 h after the administration of a serotonin receptor antagonist/reminder. We hypothesize that the mechanisms of amnesia induction caused by impaired memory reconsolidation depend on protein and mRNA syntheses within a certain time window, similar to the mechanisms of induction of other long-term plastic brain rearrangements.
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Affiliation(s)
- Vladimir P Nikitin
- P.K. Anokhin Research Institute of Normal Physiology, Laboratory of Functional Neurochemistry, Baltiyskala Str. 8, 125315, Moscow, Russian Federation.
| | - Svetlana V Solntseva
- P.K. Anokhin Research Institute of Normal Physiology, Laboratory of Functional Neurochemistry, Baltiyskala Str. 8, 125315, Moscow, Russian Federation
| | - Sergey A Kozyrev
- P.K. Anokhin Research Institute of Normal Physiology, Laboratory of Functional Neurochemistry, Baltiyskala Str. 8, 125315, Moscow, Russian Federation
| | - Pavel V Nikitin
- P.K. Anokhin Research Institute of Normal Physiology, Laboratory of Functional Neurochemistry, Baltiyskala Str. 8, 125315, Moscow, Russian Federation; N.N. Burdenko National Medical Research Center of Neurosurgery, Department of Neuropathology and Molecular Diagnostics, Moscow, Russian Federation
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15
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Shail MS. Using Micro-learning on Mobile Applications to Increase Knowledge Retention and Work Performance: A Review of Literature. Cureus 2019; 11:e5307. [PMID: 31511813 PMCID: PMC6716752 DOI: 10.7759/cureus.5307] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Micro-learning is an educational teaching method used to train users on multiple platforms. This article will provide a brief introduction to the concepts of short-term and long-term memory, and explain how micro-learning can be used to increase retention in learners. Micro-lessons can aid in negating the Ebbinghaus forgetting curve and can use reintroduction to keep retention at significantly higher levels. This process also speeds up the learning process overall because students avoid the phenomenon of mental fatigue. The article cites studies suggesting mental fatigue can cause serious cognitive decline in individual performance. By breaking complex courses into manageable smaller lessons, micro-learning preserves the neurotransmitter cascade for steady neurochemical performance. By using mobile devices, students can pause and continue their micro-lessons with ease. The mobile application also gives them the opportunity to continually check on their performance, and adjust their learning accordingly. Micro-learning on mobile devices also keeps engagement levels high because it utilizes different forms of media to keep users captivated.
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Affiliation(s)
- Mrigank S Shail
- Medicine, Xavier University School of Medicine, Toronto, CAN
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16
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Schicknick H, Henschke JU, Budinger E, Ohl FW, Gundelfinger ED, Tischmeyer W. β-adrenergic modulation of discrimination learning and memory in the auditory cortex. Eur J Neurosci 2019; 50:3141-3163. [PMID: 31162753 PMCID: PMC6900137 DOI: 10.1111/ejn.14480] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 05/27/2019] [Accepted: 05/31/2019] [Indexed: 01/11/2023]
Abstract
Despite vast literature on catecholaminergic neuromodulation of auditory cortex functioning in general, knowledge about its role for long‐term memory formation is scarce. Our previous pharmacological studies on cortex‐dependent frequency‐modulated tone‐sweep discrimination learning of Mongolian gerbils showed that auditory‐cortical D1/5‐dopamine receptor activity facilitates memory consolidation and anterograde memory formation. Considering overlapping functions of D1/5‐dopamine receptors and β‐adrenoceptors, we hypothesised a role of β‐adrenergic signalling in the auditory cortex for sweep discrimination learning and memory. Supporting this hypothesis, the β1/2‐adrenoceptor antagonist propranolol bilaterally applied to the gerbil auditory cortex after task acquisition prevented the discrimination increment that was normally monitored 1 day later. The increment in the total number of hurdle crossings performed in response to the sweeps per se was normal. Propranolol infusion after the seventh training session suppressed the previously established sweep discrimination. The suppressive effect required antagonist injection in a narrow post‐session time window. When applied to the auditory cortex 1 day before initial conditioning, β1‐adrenoceptor‐antagonising and β1‐adrenoceptor‐stimulating agents retarded and facilitated, respectively, sweep discrimination learning, whereas β2‐selective drugs were ineffective. In contrast, single‐sweep detection learning was normal after propranolol infusion. By immunohistochemistry, β1‐ and β2‐adrenoceptors were identified on the neuropil and somata of pyramidal and non‐pyramidal neurons of the gerbil auditory cortex. The present findings suggest that β‐adrenergic signalling in the auditory cortex has task‐related importance for discrimination learning of complex sounds: as previously shown for D1/5‐dopamine receptor signalling, β‐adrenoceptor activity supports long‐term memory consolidation and reconsolidation; additionally, tonic input through β1‐adrenoceptors may control mechanisms permissive for memory acquisition.
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Affiliation(s)
- Horst Schicknick
- Special Lab Molecular Biological Techniques, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Julia U Henschke
- Department Systems Physiology of Learning, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Institute of Cognitive Neurology and Dementia Research, Otto von Guericke University Magdeburg, Magdeburg, Germany
| | - Eike Budinger
- Department Systems Physiology of Learning, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Center for Behavioral Brain Sciences, Magdeburg, Germany
| | - Frank W Ohl
- Department Systems Physiology of Learning, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Center for Behavioral Brain Sciences, Magdeburg, Germany.,Institute of Biology, Otto von Guericke University Magdeburg, Magdeburg, Germany
| | - Eckart D Gundelfinger
- Center for Behavioral Brain Sciences, Magdeburg, Germany.,Department Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Molecular Neurobiology, Medical Faculty, Otto von Guericke University Magdeburg, Magdeburg, Germany
| | - Wolfgang Tischmeyer
- Special Lab Molecular Biological Techniques, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Center for Behavioral Brain Sciences, Magdeburg, Germany
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17
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Zhang GR, Zhao H, Choi EM, Svestka M, Wang X, Nagayach A, Singh A, Cook RG, Geller AI. An identified ensemble within a neocortical circuit encodes essential information for genetically-enhanced visual shape learning. Hippocampus 2019; 29:710-725. [PMID: 30734387 DOI: 10.1002/hipo.23068] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 12/04/2018] [Accepted: 12/20/2018] [Indexed: 12/31/2022]
Abstract
Advanced cognitive tasks are encoded in distributed neocortical circuits that span multiple forebrain areas. Nonetheless, synaptic plasticity and neural network theories hypothesize that essential information for performing these tasks is encoded in specific ensembles within these circuits. Relatively simpler subcortical areas contain specific ensembles that encode learning, suggesting that neocortical circuits contain such ensembles. Previously, using localized gene transfer of a constitutively active protein kinase C (PKC), we established that a genetically-modified circuit in rat postrhinal cortex, part of the hippocampal formation, can encode some essential information for performing specific visual shape discriminations. However, these studies did not identify any specific neurons that encode learning; the entire circuit might be required. Here, we show that both learning and recall require fast neurotransmitter release from an identified ensemble within this circuit, the transduced neurons; we blocked fast release from these neurons by coexpressing a Synaptotagmin I siRNA with the constitutively active PKC. During learning or recall, specific signaling pathways required for learning are activated in this ensemble; during learning, calcium/calmodulin-dependent protein kinase II, MAP kinase, and CREB are activated; and, during recall, dendritic protein synthesis and CREB are activated. Using activity-dependent gene imaging, we showed that during learning, activity in this ensemble is required to recruit and activate the circuit. Further, after learning, during image presentation, blocking activity in this ensemble reduces accuracy, even though most of the rest of the circuit is activated. Thus, an identified ensemble within a neocortical circuit encodes essential information for performing an advanced cognitive task.
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Affiliation(s)
- Guo-Rong Zhang
- Department of Neurology, W. Roxbury VA Hospital/Harvard Medical School, W. Roxbury, Massachusetts
| | - Hua Zhao
- Department of Neurology, W. Roxbury VA Hospital/Harvard Medical School, W. Roxbury, Massachusetts
| | - Eui M Choi
- Department of Neurology, W. Roxbury VA Hospital/Harvard Medical School, W. Roxbury, Massachusetts
| | - Michael Svestka
- Department of Neurology, W. Roxbury VA Hospital/Harvard Medical School, W. Roxbury, Massachusetts
| | - Xiaodan Wang
- Department of Neurology, W. Roxbury VA Hospital/Harvard Medical School, W. Roxbury, Massachusetts
| | - Aarti Nagayach
- Department of Ophthalmology, Louisiana State University Health Sciences Center, New Orleans, Louisiana
| | - Anshuman Singh
- Department of Ophthalmology, Louisiana State University Health Sciences Center, New Orleans, Louisiana
| | - Robert G Cook
- Department of Psychology, Tufts University, Medford, Massachusetts
| | - Alfred I Geller
- Department of Neurology, W. Roxbury VA Hospital/Harvard Medical School, W. Roxbury, Massachusetts.,Department of Ophthalmology, Louisiana State University Health Sciences Center, New Orleans, Louisiana.,Department of Pharmacology, Louisiana State University Health Sciences Center, New Orleans, Louisiana
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18
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Wideman CE, Jardine KH, Winters BD. Involvement of classical neurotransmitter systems in memory reconsolidation: Focus on destabilization. Neurobiol Learn Mem 2018; 156:68-79. [DOI: 10.1016/j.nlm.2018.11.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 10/09/2018] [Accepted: 11/01/2018] [Indexed: 10/27/2022]
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19
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Song Z, Chen H, Xu W, Wu S, Zhu G. Basolateral amygdala calpain is required for extinction of contextual fear-memory. Neurobiol Learn Mem 2018; 155:180-188. [PMID: 30086394 DOI: 10.1016/j.nlm.2018.08.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 06/25/2018] [Accepted: 08/03/2018] [Indexed: 02/07/2023]
Abstract
Extinction of fear-memory is essential for emotional and mental changes. However, the mechanisms underlying extinction of fear-memory are largely unknown. Calpain is a type of calcium-dependent protease that plays a critical role in memory consolidation and reconsolidation. Whether calpain functions in extinction of fear-memory is unknown, as are the molecular mechanisms. In this study, we investigated the pivotal role of calpain in extinction of fear-memory in mice, and assessed its mechanism. Conditioned stimulation/unconditioned stimulation-conditioned stimulation paradigms combined with pharmacological methods were employed to evaluate the action of calpain in memory extinction. Our data demonstrated that intraperitoneal or intra-basolateral amygdala (BLA) injection of calpain inhibitors could eliminate extinction of fear-memory in mice. Moreover, extinction of fear-memory paradigm-activated BLA calpain activity, which degraded suprachiasmatic nucleus circadian oscillatory protein (SCOP) and phosphatase and tensin homolog (PTEN), subsequently contributing to activation of a protein kinase B (AKT)-mammalian target of the rapamycin (mTor) signaling pathway. Additionally, cAMP-response element binding protein (CREB) phosphorylation was also augmented following extinction of fear-memory. Calpain inhibitor blocked the signaling pathway activation induced by extinction of fear-memory. Additionally, intra-BLA injection of rapamycin or cycloheximide also blocked the extinction of fear-memory. Conversely, intra-BLA injection of PTEN inhibitor, bpV, reversed the effect of calpeptin on extinction of fear-memory. Together, our data confirmed the function of BLA calpain in extinction of fear-memory, likely via degrading PTEN and activating AKT-mTor-dependent protein synthesis.
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Affiliation(s)
- Zhujin Song
- Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei 230038, China
| | - Hui Chen
- Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei 230038, China
| | - Wen Xu
- Department of Neurology, The first Affiliated Hospital of University of Science and Technology of China, Anhui Provincial Hospital, Hefei 230001, China
| | - Shengbing Wu
- Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei 230038, China; Anhui Academy of Chinese Medicine, Hefei 230038, China
| | - Guoqi Zhu
- Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei 230038, China; Anhui Academy of Chinese Medicine, Hefei 230038, China.
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20
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Abstract
Understanding how stored information emerges is a main question in the neurobiology of memory that is now increasingly gaining attention. However, molecular events underlying this memory stage, including involvement of protein synthesis, are not well defined. Mammalian target of rapamycin complex 1 (mTORC1), a central regulator of protein synthesis, has been implicated in synaptic plasticity and is required for memory formation. Using inhibitory avoidance (IA), we evaluated the role of mTORC1 in memory retrieval. Infusion of a selective mTORC1 inhibitor, rapamycin, into the dorsal hippocampus 15 or 40 min but not 3 h before testing at 24 h reversibly disrupted memory expression even in animals that had already expressed IA memory. Emetine, a general protein synthesis inhibitor, provoked a similar impairment. mTORC1 inhibition did not interfere with short-term memory retrieval. When infused before test at 7 or 14 but not at 28 days after training, rapamycin impaired memory expression. mTORC1 blockade in retrosplenial cortex, another structure required for IA memory, also impaired memory retention. In addition, pretest intrahippocampal rapamycin infusion impaired object location memory retrieval. Our results support the idea that ongoing protein synthesis mediated by activation of mTORC1 pathway is necessary for long but not for short term memory.
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21
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Yue J, Shi L, Lin X, Khan MZ, Shi J, Lu L. Behavioral interventions to eliminate fear responses. SCIENCE CHINA-LIFE SCIENCES 2018; 61:625-632. [PMID: 29744783 DOI: 10.1007/s11427-018-9294-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 02/26/2018] [Indexed: 02/07/2023]
Abstract
Fear memory underlies anxiety-related disorders, including posttraumatic stress disorder (PTSD). PTSD is a fear-based disorder, characterized by difficulties in extinguishing the learned fear response and maintaining extinction. Currently, the first-line treatment for PTSD is exposure therapy, which forms an extinction memory to compete with the original fear memory. However, the extinguished fear often returns under numerous circumstances, suggesting that novel methods are needed to eliminate fear memory or facilitate extinction memory. This review discusses research that targeted extinction and reconsolidation to manipulate fear memory. Recent studies indicate that sleep is an active state that can regulate memory processes. We also discuss the influence of sleep on fear memory. For each manipulation, we briefly summarize the neural mechanisms that have been identified in human studies. Finally, we highlight potential limitations and future directions in the field to better translate existing interventions to clinical settings.
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Affiliation(s)
- Jingli Yue
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key of Mental Health, Ministry of Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, 100191, China
| | - Le Shi
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key of Mental Health, Ministry of Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, 100191, China.,National Institute on Drug Dependence, Peking University, Beijing, 100191, China
| | - Xiao Lin
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key of Mental Health, Ministry of Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, 100191, China.,Peking-Tsinghua Center for Life Sciences and PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Muhammad Zahid Khan
- National Institute on Drug Dependence, Peking University, Beijing, 100191, China
| | - Jie Shi
- National Institute on Drug Dependence, Peking University, Beijing, 100191, China
| | - Lin Lu
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key of Mental Health, Ministry of Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, 100191, China. .,National Institute on Drug Dependence, Peking University, Beijing, 100191, China. .,Peking-Tsinghua Center for Life Sciences and PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China.
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22
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MacLeod S, Reynolds MG, Lehmann H. The mitigating effect of repeated memory reactivations on forgetting. NPJ SCIENCE OF LEARNING 2018; 3:9. [PMID: 30631470 PMCID: PMC6220336 DOI: 10.1038/s41539-018-0025-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 03/27/2018] [Accepted: 04/04/2018] [Indexed: 06/09/2023]
Abstract
Memory reactivation is a process whereby cueing or recalling a long-term memory makes it enter a new active and labile state. Substantial evidence suggests that during this state the memory can be updated (e.g., adding information) and can become more vulnerable to disruption (e.g., brain insult). Memory reactivations can also prevent memory decay or forgetting. However, it is unclear whether cueing recall of a feature or component of the memory can benefit retention similarly to promoting recall of the entire memory. We examined this possibility by having participants view a series of neutral images and then randomly assigning them to one of four reactivation groups: control (no reactivation), distractor (reactivation of experimental procedures), component (image category reactivation), and descriptive (effortful description of the images). The experiment also included three retention intervals: 1 h, 9 days, and 28 days. Importantly, the participants received three reactivations equally spaced within their respective retention interval. At the end of the interval, all the participants were given an in-lab free-recall test in which they were asked to write down each image they remembered with as many details as possible. The data revealed that both the participants in the descriptive reactivation and component reactivation groups remembered significantly more than the participants in the control groups, with the effect being most pronounced in the 28-day retention interval condition. These findings suggest that memory reactivation, even component reactivation of a memory, makes memories more resistant to decay.
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Affiliation(s)
- Sydney MacLeod
- Psychology Department, Trent University, Peterborough, ON Canada
| | | | - Hugo Lehmann
- Psychology Department, Trent University, Peterborough, ON Canada
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23
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Loprinzi PD, Edwards MK, Frith E. Potential avenues for exercise to activate episodic memory-related pathways: a narrative review. Eur J Neurosci 2017; 46:2067-2077. [PMID: 28700099 DOI: 10.1111/ejn.13644] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/06/2017] [Accepted: 07/07/2017] [Indexed: 12/13/2022]
Abstract
Memory function plays an important role in activities of daily living, and consequently, quality and quantity of life. In this narrative review, we discuss the anatomical components of episodic memory, including the structure of the hippocampus and the routes of communication to and from this structure. We also highlight cellular traces of memory, such as the engram cell and pathway. To provide etiological insight, the biological mechanisms of episodic memory are discussed, including factors subserving memory encoding (e.g., cognitive attention, neuroelectrical indices), consolidation (i.e., synaptic and brain systems level), and retrieval (e.g., availability of cues, context-dependent, state-dependent, and cognitive processing). Central to this manuscript, we highlight how exercise may influence each of these aforementioned parameters (e.g., exercise-induced hippocampal growth, synaptic plasticity, and cue retrieval) and then discuss the implications of these findings to enhance and preserve memory function. Collectively, this narrative review briefly summarizes potential mechanisms of episodic memory, and how exercise may activate these mechanistic pathways.
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Affiliation(s)
- Paul D Loprinzi
- Jackson Heart Study Vanguard Center at Oxford, Physical Activity Epidemiology Laboratory, Exercise Psychology Laboratory, Department of Health, Exercise Science and Recreation Management, The University of Mississippi, University, MS, USA
| | - Meghan K Edwards
- Physical Activity Epidemiology Laboratory, Exercise Psychology Laboratory, Department of Health, Exercise Science and Recreation Management, The University of Mississippi, University, MS, USA
| | - Emily Frith
- Physical Activity Epidemiology Laboratory, Exercise Psychology Laboratory, Department of Health, Exercise Science and Recreation Management, The University of Mississippi, University, MS, USA
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