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Smies CW, Bellfy L, Wright DS, Bennetts SG, Urban MW, Brunswick CA, Shu G, Kwapis JL. Pharmacological HDAC3 inhibition alters memory updating in young and old male mice. Front Mol Neurosci 2024; 17:1429880. [PMID: 38989157 PMCID: PMC11234845 DOI: 10.3389/fnmol.2024.1429880] [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: 05/08/2024] [Accepted: 06/17/2024] [Indexed: 07/12/2024] Open
Abstract
Long-term memories are not stored in a stable state but must be flexible and dynamic to maintain relevance in response to new information. Existing memories are thought to be updated through the process of reconsolidation, in which memory retrieval initiates destabilization and updating to incorporate new information. Memory updating is impaired in old age, yet little is known about the mechanisms that go awry. One potential mechanism is the repressive histone deacetylase 3 (HDAC3), which is a powerful negative regulator of memory formation that contributes to age-related impairments in memory formation. Here, we tested whether HDAC3 also contributes to age-related impairments in memory updating using the Objects in Updated Locations (OUL) paradigm. We show that blocking HDAC3 immediately after updating with the pharmacological inhibitor RGFP966 ameliorated age-related impairments in memory updating in 18-m.o. male mice. Surprisingly, we found that post-update HDAC3 inhibition in young (3-m.o.) male mice had no effect on memory updating but instead impaired memory for the original information, suggesting that the original and updated information may compete for expression at test and HDAC3 helps regulate which information is expressed. To test this idea, we next assessed whether HDAC3 inhibition would improve memory updating in young male mice given a weak, subthreshold update. Consistent with our hypothesis, we found that HDAC3 blockade strengthened the subthreshold update without impairing memory for the original information, enabling balanced expression of the original and updated information. Together, this research suggests that HDAC3 may contribute to age-related impairments in memory updating and may regulate the strength of a memory update in young mice, shifting the balance between the original and updated information at test.
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Affiliation(s)
- Chad W. Smies
- Department of Biology, Pennsylvania State University, University Park, PA, United States
- Center for the Molecular Investigation of Neurological Disorders (CMIND), The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, United States
| | - Lauren Bellfy
- Department of Biology, Pennsylvania State University, University Park, PA, United States
- Center for the Molecular Investigation of Neurological Disorders (CMIND), The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, United States
| | - Destiny S. Wright
- Department of Biology, Pennsylvania State University, University Park, PA, United States
- Center for the Molecular Investigation of Neurological Disorders (CMIND), The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, United States
| | - Sofia G. Bennetts
- Department of Biology, Pennsylvania State University, University Park, PA, United States
- Center for the Molecular Investigation of Neurological Disorders (CMIND), The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, United States
| | - Mark W. Urban
- Department of Biology, Pennsylvania State University, University Park, PA, United States
- Center for the Molecular Investigation of Neurological Disorders (CMIND), The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, United States
| | - Chad A. Brunswick
- Department of Biology, Pennsylvania State University, University Park, PA, United States
- Center for the Molecular Investigation of Neurological Disorders (CMIND), The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, United States
| | - Guanhua Shu
- Department of Biology, Pennsylvania State University, University Park, PA, United States
- Center for the Molecular Investigation of Neurological Disorders (CMIND), The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, United States
| | - Janine L. Kwapis
- Department of Biology, Pennsylvania State University, University Park, PA, United States
- Center for the Molecular Investigation of Neurological Disorders (CMIND), The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, United States
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Smies CW, Bellfy L, Wright DS, Bennetts SS, Urban MW, Brunswick CA, Shu G, Kwapis JL. Pharmacological HDAC3 inhibition alters memory updating in young and old mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.08.593015. [PMID: 38766057 PMCID: PMC11100699 DOI: 10.1101/2024.05.08.593015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Long-term memories are not stored in a stable state but must be flexible and dynamic to maintain relevance in response to new information. Existing memories are thought to be updated through the process of reconsolidation, in which memory retrieval initiates destabilization and updating to incorporate new information. Memory updating is impaired in old age, yet little is known about the mechanisms that go awry. One potential mechanism is the repressive histone deacetylase 3 (HDAC3), which is a powerful negative regulator of memory formation that contributes to age-related impairments in memory formation. Here, we tested whether HDAC3 also contributes to age-related impairments in memory updating using the Objects in Updated Locations (OUL) paradigm. We show that blocking HDAC3 immediately after updating with the pharmacological inhibitor RGFP966 ameliorated age-related impairments in memory updating in 18-m.o. mice. Surprisingly, we found that post-update HDAC3 inhibition in young (3-m.o.) mice had no effect on memory updating but instead impaired memory for the original information, suggesting that the original and updated information may compete for expression at test and HDAC3 helps regulate which information is expressed. To test this idea, we next assessed whether HDAC3 inhibition would improve memory updating in young mice given a weak, subthreshold update. Consistent with our hypothesis, we found that HDAC3 blockade strengthened the subthreshold update without impairing memory for the original information, enabling balanced expression of the original and updated information. Together, this research suggests that HDAC3 may contribute to age-related impairments in memory updating and may regulate the strength of a memory update in young mice, shifting the balance between the original and updated information at test.
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Sepahvand T, Power KD, Qin T, Yuan Q. The Basolateral Amygdala: The Core of a Network for Threat Conditioning, Extinction, and Second-Order Threat Conditioning. BIOLOGY 2023; 12:1274. [PMID: 37886984 PMCID: PMC10604397 DOI: 10.3390/biology12101274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 09/14/2023] [Accepted: 09/20/2023] [Indexed: 10/28/2023]
Abstract
Threat conditioning, extinction, and second-order threat conditioning studied in animal models provide insight into the brain-based mechanisms of fear- and anxiety-related disorders and their treatment. Much attention has been paid to the role of the basolateral amygdala (BLA) in such processes, an overview of which is presented in this review. More recent evidence suggests that the BLA serves as the core of a greater network of structures in these forms of learning, including associative and sensory cortices. The BLA is importantly regulated by hippocampal and prefrontal inputs, as well as by the catecholaminergic neuromodulators, norepinephrine and dopamine, that may provide important prediction-error or learning signals for these forms of learning. The sensory cortices may be required for the long-term storage of threat memories. As such, future research may further investigate the potential of the sensory cortices for the long-term storage of extinction and second-order conditioning memories.
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Affiliation(s)
| | | | | | - Qi Yuan
- Biomedical Sciences, Faculty of Medicine, Memorial University, St John’s, NL A1B 3V6, Canada; (T.S.); (K.D.P.); (T.Q.)
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Zuzina AB, Vinarskaya AK, Balaban PM. DNA Methylation Inhibition Reversibly Impairs the Long-Term Context Memory Maintenance in Helix. Int J Mol Sci 2023; 24:14068. [PMID: 37762369 PMCID: PMC10531757 DOI: 10.3390/ijms241814068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 09/08/2023] [Accepted: 09/10/2023] [Indexed: 09/29/2023] Open
Abstract
This work aims to study the epigenetic mechanisms of regulating long-term context memory in the gastropod mollusk: Helix. We have shown that RG108, an inhibitor of DNA methyltransferase (DNMT), impaired long-term context memory in snails, and this impairment can be reversed within a limited time window: no more than 48 h. Research on the mechanisms through which the long-term context memory impaired by DNMT inhibition could be reinstated demonstrated that this effect depends on several biochemical mechanisms: nitric oxide synthesis, protein synthesis, and activity of the serotonergic system. Memory recovery did not occur if at least one of these mechanisms was impaired. The need for the joint synergic activity of several biochemical systems for a successful memory rescue confirms the assumption that the memory recovery process depends on the process of active reconsolidation, and is not simply a passive weakening of the effect of RG108 over time. Finally, we showed that the reactivation of the impaired memory by RG108, followed by administration of histone deacetylase inhibitor sodium butyrate, led to memory recovery only within a narrow time window: no more than 48 h after memory disruption.
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Affiliation(s)
| | | | - Pavel M. Balaban
- Cellular Neurobiology of Learning Lab, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, 5A Butlerova St., Moscow 117485, Russia; (A.B.Z.); (A.K.V.)
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Damiani F, Cornuti S, Tognini P. The gut-brain connection: Exploring the influence of the gut microbiota on neuroplasticity and neurodevelopmental disorders. Neuropharmacology 2023; 231:109491. [PMID: 36924923 DOI: 10.1016/j.neuropharm.2023.109491] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 02/22/2023] [Accepted: 03/05/2023] [Indexed: 03/17/2023]
Abstract
Neuroplasticity refers to the ability of brain circuits to reorganize and change the properties of the network, resulting in alterations in brain function and behavior. It is traditionally believed that neuroplasticity is influenced by external stimuli, learning, and experience. Intriguingly, there is new evidence suggesting that endogenous signals from the body's periphery may play a role. The gut microbiota, a diverse community of microorganisms living in harmony with their host, may be able to influence plasticity through its modulation of the gut-brain axis. Interestingly, the maturation of the gut microbiota coincides with critical periods of neurodevelopment, during which neural circuits are highly plastic and potentially vulnerable. As such, dysbiosis (an imbalance in the gut microbiota composition) during early life may contribute to the disruption of normal developmental trajectories, leading to neurodevelopmental disorders. This review aims to examine the ways in which the gut microbiota can affect neuroplasticity. It will also discuss recent research linking gastrointestinal issues and bacterial dysbiosis to various neurodevelopmental disorders and their potential impact on neurological outcomes.
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Affiliation(s)
| | - Sara Cornuti
- Laboratory of Biology, Scuola Normale Superiore, Pisa, Italy
| | - Paola Tognini
- Laboratory of Biology, Scuola Normale Superiore, Pisa, Italy; Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.
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Ferrara NC, Kwapis JL, Trask S. Memory retrieval, reconsolidation, and extinction: Exploring the boundary conditions of post-conditioning cue exposure. Front Synaptic Neurosci 2023; 15:1146665. [PMID: 36937567 PMCID: PMC10017482 DOI: 10.3389/fnsyn.2023.1146665] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 02/17/2023] [Indexed: 03/06/2023] Open
Abstract
Following fear conditioning, behavior can be reduced by giving many CS-alone presentations in a process known as extinction or by presenting a few CS-alone presentations and interfering with subsequent memory reconsolidation. While the two share procedural similarities, both the behavioral outcomes and the neurobiological underpinnings are distinct. Here we review the neural and behavioral mechanisms that produce these separate behavioral reductions, as well as some factors that determine whether or not a retrieval-dependent reconsolidation process or an extinction process will be in effect.
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Affiliation(s)
- Nicole C. Ferrara
- Discipline of Physiology and Biophysics, Rosalind Franklin University, North Chicago, IL, United States
- Center for Neurobiology of Stress Resilience and Psychiatric Disorders, Rosalind Franklin University, North Chicago, IL, United States
| | - Janine L. Kwapis
- Department of Biology, The Pennsylvania State University, University Park, PA, United States
| | - Sydney Trask
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, United States
- Purdue Institute for Integrative Neuroscience, West Lafayette, IN, United States
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Solntseva SV, Nikitin VP, Kozyrev SA, Nikitin PV. DNA methylation inhibition participates in the anterograde amnesia key mechanism through the suppression of the transcription of genes involved in memory formation in grape snails. Behav Brain Res 2023; 437:114118. [PMID: 36116736 DOI: 10.1016/j.bbr.2022.114118] [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: 07/12/2022] [Revised: 09/13/2022] [Accepted: 09/14/2022] [Indexed: 11/16/2022]
Abstract
The study of the amnesia mechanisms is of both theoretical and practical importance. The mechanisms of anterograde amnesia are the least studied, due to the lack of an experimental model that allows studying this amnesia type molecular and cellular mechanisms. Previously, we found that conditional food aversion memory reconsolidation impairment in snails by NMDA glutamate receptor antagonists led to the amnesia induction, in the late stages of which (>10 days) repeated training did not cause long-term memory formation. In the same animals, long-term memory aversion to a new food type was formed. We characterized this amnesia as specific anterograde amnesia. In the present work we studied the role of epigenetic DNA methylation processes as well as protein and mRNA synthesis in the mechanisms of anterograde amnesia and memory recovery. DNMT methyltransferase inhibitors (iDNMT: zebularine, RG108 (N-Phthalyl-1-tryptophan), and 5-AZA (5-Aza-2'-deoxycytidine)) were used to alter DNA methylation. It was found that in amnesic animals the iDNMT administration before or after shortened repeated training led to the rapid long-term conditional food aversion formation (Ebbinghaus saving effect). This result suggests that amnestic animals retain a latent memory, which is the basis for accelerated memory formation during repeated training. Protein synthesis inhibitors administration (cycloheximide) before or immediately after repeated training or administration of RNA synthesis inhibitor (actinomycin D) after repeated training prevented memory formation under iDNMT action. The earlier protein synthesis inhibitor effect suggests that the proteins required for memory formation are translated from the pre-existing, translationally repressed mRNAs. Thus, we have shown for the first time that the anterograde amnesia key mechanism is DNMT-dependent suppression of the transcription of genes involved in memory mechanisms. Inhibition of DNMT during repeated training reversed these genes expression blockade, opening access to them by transcription factors synthesized during training from the pre-existing mRNAs.
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Affiliation(s)
- S V Solntseva
- Laboratory of Functional Neurochemistry, P.K. Anokhin Institute of Normal Physiology, Moscow 125315, Russia.
| | - V P Nikitin
- Laboratory of Functional Neurochemistry, P.K. Anokhin Institute of Normal Physiology, Moscow 125315, Russia.
| | - S A Kozyrev
- Laboratory of Functional Neurochemistry, P.K. Anokhin Institute of Normal Physiology, Moscow 125315, Russia.
| | - P V Nikitin
- Laboratory of Functional Neurochemistry, P.K. Anokhin Institute of Normal Physiology, Moscow 125315, Russia.
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Sanders AR, Bhongir N, vonHoldt B, Pellegrini M. Association of DNA methylation with energy and fear-related behaviors in canines. Front Psychol 2022; 13:1025494. [PMID: 36591016 PMCID: PMC9794564 DOI: 10.3389/fpsyg.2022.1025494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 11/17/2022] [Indexed: 12/15/2022] Open
Abstract
Introduction Behavioral traits are influenced by gene by environment interactions. To study the genetic and epigenetic components of behavior, we analyzed whether dog behavioral traits could be predicted by their DNA methylation and genotypes. Methods We conducted an analysis on dog behaviors such as sociability, trainability and energy as measured by Canine Behavioral and Research Assessment Questionnaire (C-BARQ) behavioral surveys paired with buccal swabs from 46 dogs. Previously we used targeted bisulfite sequencing to analyze DNA methylation and collected genotype data from over 1,500 single nucleotide polymorphisms (SNPs). Owner-reported C-BARQ responses were used to quantify 14 behavioral trait values. Results Using Partial Least Squares (PLS) Regression analysis we found behavioral traits such as energy, attachment/attention-seeking, non-social fear, and stranger-directed fear to be significantly associated with DNA methylation across 3,059 loci. After we adjusted for age as a confounding variable, energy and stranger-directed fear remained significantly associated with methylation. We found that most behavioral traits were not predictable by our limited set of SNPs. Discussion By identifying individual genes whose methylation is significantly associated with behavioral traits, we generate hypotheses about possible mechanisms involved in behavioral regulation. Overall, our study extends previous work in behavioral epigenetics, shows that canine behaviors are predictable by DNA methylation, and serves as a proof of concept for future studies in behavioral epigenetics.
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Affiliation(s)
- Abigail R. Sanders
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Neha Bhongir
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Bridgett vonHoldt
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, United States
| | - Matteo Pellegrini
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, United States,*Correspondence: Matteo Pellegrini,
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Environmental enrichment mitigates PTSD-like behaviors in adult male rats exposed to early life stress by regulating histone acetylation in the hippocampus and amygdala. J Psychiatr Res 2022; 155:120-136. [PMID: 36029624 DOI: 10.1016/j.jpsychires.2022.07.067] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 07/04/2022] [Accepted: 07/25/2022] [Indexed: 11/20/2022]
Abstract
Early life stress (ELS) can cause long-term changes in gene expression, affect cognition, mood, and behavior, and increase susceptibility to post-traumatic stress disorder (PTSD) in adulthood, in which the histone acetylation plays a crucial role. Studies have found that environmental enrichment (EE) mitigated the unfavorable outcomes of ELS. However, the underlying mechanism of the histone acetylation is not yet completely clear. The purpose of this study was to explore the effect of EE on the histone acetylation after ELS. In this study, using single prolonged stress (SPS) paradigm in early adolescent rats explored the long-term effects of ELS on behavior, the activity of histone acetyltransferases (HATs) and histone deacetylases (HDACs), as well as the acetylation levels of the lysine 9 site of histone H3 (H3K9) and lysine 12 site of histone H4 (H4K12) in the hippocampus and amygdala. Meanwhile, the protective effects of EE intervention were examined. We found that adult male rats exposed to ELS showed behavioral changes, including reduced locomotor activity, increased anxiety-like behaviors, impaired spatial learning and memory, enhanced contextual and cued fear memory, and the HATs/HDACs ratio and acetyl H3K9 (Ac-H3K9) and acetyl H4K12 (Ac-H4K12) were increased in the hippocampus and decreased in the amygdala. Furthermore, EE attenuated the behavioral abnormalities from ELS, possibly through down-regulating the activity of HATs in the hippocampus and up-regulating HDACs activities in the amygdala. These finding suggested that EE could ameliorate ELS-induced PTSD-like behaviors by regulating histone acetylation in the hippocampus and amygdala, reducing the susceptibility to PTSD in adulthood.
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Reich N, Hölscher C. Beyond Appetite: Acylated Ghrelin As A Learning, Memory and Fear Behavior-modulating Hormone. Neurosci Biobehav Rev 2022; 143:104952. [DOI: 10.1016/j.neubiorev.2022.104952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 04/27/2022] [Accepted: 11/05/2022] [Indexed: 11/10/2022]
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Effects of 5-Aza on neurogenesis contribute to learning and memory in the mouse hippocampus. Biomed Pharmacother 2022; 154:113623. [PMID: 36081289 DOI: 10.1016/j.biopha.2022.113623] [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: 06/01/2022] [Revised: 08/26/2022] [Accepted: 08/29/2022] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND 5-Aza-2'-deoxycytidine (5-Aza-CdR) is a demethylating agent that has various biological effects related to DNA methylation. DNA methylation plays important roles in learning and memory. We have reported that 5-Aza-CdR improved the performance of mice in the water maze and step-down tests. Some behaviours have been well recognized to be mediated by neurogenesis in the hippocampus. The Notch signalling pathway plays a key role in adult hippocampal neurogenesis. In this study, we examined whether 5-Aza-CdR (DNA methyltransferase inhibitor) affects neurogenesis and Notch1 expression. METHODS The learning and memory behaviour of mice was evaluated by a conditioned avoidance learning 24 h after 5-Aza-CdR treatment. The mRNA and protein expression levels of Notch1 and HES1 were measured by real-time PCR and Western blotting. The 5-bromo-2'-deoxyuridine (BrdU)-positive cells and the expression of Notch1 in the hippocampal DG were observed through laser confocal microscopy. To further clarify whether 5-Aza-CdR affects behaviour through neurogenesis, the expression level of Notch1, cell viability and cell cycle were analysed using the HT22 cell line. RESULTS The behaviour in conditioned avoidance learning was improved, while neurogenesis and the Notch1 pathway were increased in the hippocampus of mice that were injected with 5-Aza-CdR. In vitro experiments showed that 5-Aza-CdR increased the expression of the Notch1 pathway and upregulated S-phase in the cell cycle and cell viability. CONCLUSIONS Our results suggest that the effect of 5-Aza-CdR on behaviour may be related to an increase in neurogenesis with upregulation of the Notch1 pathway in the hippocampus.
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Qian S, Shi C, Huang S, Yang C, Luo Y. DNA methyltransferase activity in the basolateral amygdala is critical for reconsolidation of a heroin reward memory. Front Mol Neurosci 2022; 15:1002139. [PMID: 36176958 PMCID: PMC9513049 DOI: 10.3389/fnmol.2022.1002139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 08/18/2022] [Indexed: 11/17/2022] Open
Abstract
The persistence of drug memory contributes to relapse to drug seeking. The association between repeated drug exposure and drug-related cues leads to cravings triggered by drug-paired cues. The erasure of drug memories has been considered a promising way to inhibit cravings and prevent relapse. The re-exposure to drug-related cues destabilizes well-consolidated drug memories, during which a de novo protein synthesis-dependent process termed “reconsolidation” occurs to restabilize the reactivated drug memory. Disrupting reconsolidation of drug memories leads to the attenuation of drug-seeking behavior in both animal models and people with addictions. Additionally, epigenetic mechanisms regulated by DNA methyltransferase (DNMT) are involved in the reconsolidation of fear and cocaine reward memory. In the present study, we investigated the role of DNMT in the reconsolidation of heroin reward memory. In the heroin self-administration model in rats, we tested the effects of DNMT inhibition during the reconsolidation process on cue-induced reinstatement, heroin-priming-induced reinstatement, and spontaneous recovery of heroin-seeking behavior. We found that the bilateral infusion of 5-azacytidine (5-AZA) inhibiting DNMT into the basolateral amygdala (BLA) immediately after heroin reward memory retrieval, but not delayed 6 h after retrieval or without retrieval, decreased subsequent cue-induced and heroin-priming-induced reinstatement of heroin-seeking behavior. These findings demonstrate that inhibiting the activity of DNMT in BLA during the reconsolidation of heroin reward memory attenuates heroin-seeking behavior, which may provide a potential strategy for the therapeutic of heroin addiction.
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Affiliation(s)
- Shuyi Qian
- Department of Nephrology and Laboratory of Kidney Disease, Hunan Provincial People’s Hospital, Hunan Normal University, Changsha, China
| | - Cuijie Shi
- Hunan Province People’s Hospital, The First-Affiliated Hospital of Hunan Normal University, Changsha, China
| | - Shihao Huang
- National Institute on Drug Dependence, Beijing Key Laboratory of Drug Dependence, Peking University, Beijing, China
| | - Chang Yang
- Hunan Province People’s Hospital, The First-Affiliated Hospital of Hunan Normal University, Changsha, China
| | - Yixiao Luo
- Hunan Province People’s Hospital, The First-Affiliated Hospital of Hunan Normal University, Changsha, China
- *Correspondence: Yixiao Luo,
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Mohammadi-Farani A, Fakhri S, Jalili C, Samimi Z. Intra-mPFC injection of sodium butyrate promotes BDNF expression and ameliorates extinction recall impairment in an experimental paradigm of post-traumatic stress disorder. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2022; 25:1150-1158. [PMID: 36246060 PMCID: PMC9526891 DOI: 10.22038/ijbms.2022.65000.14312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Accepted: 08/06/2022] [Indexed: 11/08/2022]
Abstract
Objectives Therapeutic strategies that facilitate extinction are promising in the treatment of post-traumatic stress disorder (PTSD). Brain-derived neurotrophic factor (BDNF) has a crucial role in neural plasticity, a process needed for the retention of fear extinction. In this study, we investigated the effects of local administration of a histone deacetylase (HDAC) inhibitor, sodium butyrate (NaBu), on BDNF transcription and behavioral markers of extinction in the single prolonged stress (SPS) model of PTSD. Materials and Methods NaBu was infused into the infralimbic (IL) subregion of the medial prefrontal cortex (mPFC) of male rats. The freezing response was recorded as the criterion to assess fear strength on the day of extinction as well as 24 hr later in the retention test. Other behavioral tests were also measured to evaluate the anxiety level, locomotor activity, and working memory on the retention day. HDAC activity and BDNF mRNA expression were evaluated after the behavioral experiments. Results NaBu facilitated the recall of fear extinction in SPS rats (P<0.0001). SPS rats had higher HDAC activity (P<0.0001) and lower BDNF expression (P<0.05) than non-SPS animals. Also, anxiety was higher in the SPS group (P<0.0001), but locomotor activity (P=0.61) and working memory (P=0.36) were not different between SPS and Non-SPS groups. Conclusion Our findings provide evidence that the mechanism of action of NaBu in the improvement of extinction recall is mediated, in part, by enhancing histone acetylation and reviving BDNF expression in IL.
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Affiliation(s)
- Ahmad Mohammadi-Farani
- Medical Plants Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran, Department of Physiology and Pharmacology, School of medicine, Shahrekord University of Medical Sciences, Shahrekord, Iran,Corresponding author: Ahmad Mohammadi-Farani. Department of Physiology and Pharmacology, School of medicine, Shahrekord University of Medical Sciences, Shahrekord, Iran. Tel: +98-38-33333057;
| | - Sajad Fakhri
- Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Cyrus Jalili
- Medical Biology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Zahra Samimi
- Department of Immunology, School of medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
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Shang A, Bieszczad KM. Epigenetic mechanisms regulate cue memory underlying discriminative behavior. Neurosci Biobehav Rev 2022; 141:104811. [PMID: 35961385 DOI: 10.1016/j.neubiorev.2022.104811] [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: 03/31/2022] [Revised: 06/15/2022] [Accepted: 08/01/2022] [Indexed: 12/01/2022]
Abstract
The burgeoning field of neuroepigenetics has introduced chromatin modification as an important interface between experience and brain function. For example, epigenetic mechanisms like histone acetylation and DNA methylation operate throughout a lifetime to powerfully regulate gene expression in the brain that is required for experiences to be transformed into long-term memories. This review highlights emerging evidence from sensory models of memory that converge on the premise that epigenetic regulation of activity-dependent transcription in the sensory brain facilitates highly precise memory recall. Chromatin modifications may be key for neurophysiological responses to transient sensory cue features experienced in the "here and now" to be recapitulated over the long term. We conclude that the function of epigenetic control of sensory system neuroplasticity is to regulate the amount and type of sensory information retained in long-term memories by regulating neural representations of behaviorally relevant cues that guide behavior. This is of broad importance in the neuroscience field because there are few circumstances in which behavioral acts are devoid of an initiating sensory experience.
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Affiliation(s)
- Andrea Shang
- Dept. of Psychology - Behavioral and Systems Neuroscience, Rutgers University - New Brunswick, 152 Frelinghuysen Road, Piscataway, NJ 08854, USA
| | - Kasia M Bieszczad
- Dept. of Psychology - Behavioral and Systems Neuroscience, Rutgers University - New Brunswick, 152 Frelinghuysen Road, Piscataway, NJ 08854, USA; Rutgers Center for Cognitive Science (RuCCS), Rutgers University, Piscataway, NJ 08854, USA; Department of Otolaryngology - Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA.
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15
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Gold PE. Revisiting and revising memory consolidation: Personal reflections on the research legacy of Ivan Izquierdo. Neuroscience 2022; 497:4-13. [PMID: 35667494 DOI: 10.1016/j.neuroscience.2022.05.037] [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: 04/20/2022] [Accepted: 05/30/2022] [Indexed: 10/18/2022]
Abstract
Two important themes in Ivan Izquierdo's research each offered both answers and questions about the topic of memory formation and maintenance. The first theme provided evidence supporting the view that short- and long-term memory were distinct processes and could be selectively modulated by several treatments, with some affecting only short-term, others only affecting long-term memory, and still others affecting both. Over many years, Izquierdo's laboratory documented molecular responses across time after training obtaining results that showed differences as well as similarities in the biochemical changes during the first 1-2 hours and the next 4-6 hours after training, i.e., during the transition from short- to long-term memory. This work clarified the biological underpinnings of the memory processes. The second theme described waves of susceptibility of memory to enhancing and impairing treatments after time, a biphasic profile that contrasted with earlier monotonic decreases in the efficacy of memory modulating treatments as a function of time between training and treatment. Remarkably, these waves of susceptibility to modification were accompanied by biphasic changes in molecular measures at similar times after training. Remarkably, some of the molecular players exhibited persistent changes after training, with increases in levels lasting days following the training experience. These persistent molecular changes may reveal a biological basis for the dynamic nature of memories seen long after the initial memory is consolidated.
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Affiliation(s)
- Paul E Gold
- Department of Biology, Syracuse, NY, 13224, United States.
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16
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The HDAC inhibitor CI-994 acts as a molecular memory aid by facilitating synaptic and intracellular communication after learning. Proc Natl Acad Sci U S A 2022; 119:e2116797119. [PMID: 35613054 PMCID: PMC9295763 DOI: 10.1073/pnas.2116797119] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Memory formation relies on a plethora of functions, including epigenetic modifications. Over recent years, multiple studies have indicated the potential of HDAC inhibitors (HDACis) as cognitive enhancers, but their mode of action is not fully understood. Here, we tested whether HDACi treatment improves memory formation via “cognitive epigenetic priming,” stipulating that HDACis—without inherent target specificity—specifically enhance naturally occurring plasticity processes. We found that combining HDACis with fear learning, but not either treatment alone, enhances synaptic plasticity as well as memory-promoting transcriptional signaling in the hippocampus, a brain area recruited by fear learning, but not in unrelated areas. These results lend experimental support to the theory of cognitive epigenetic priming. Long-term memory formation relies on synaptic plasticity, neuronal activity-dependent gene transcription, and epigenetic modifications. Multiple studies have shown that HDAC inhibitor (HDACi) treatments can enhance individual aspects of these processes and thereby act as putative cognitive enhancers. However, their mode of action is not fully understood. In particular, it is unclear how systemic application of HDACis, which are devoid of substrate specificity, can target pathways that promote memory formation. In this study, we explore the electrophysiological, transcriptional, and epigenetic responses that are induced by CI-994, a class I HDACi, combined with contextual fear conditioning (CFC) in mice. We show that CI-994–mediated improvement of memory formation is accompanied by enhanced long-term potentiation in the hippocampus, a brain region recruited by CFC, but not in the striatum, a brain region not primarily implicated in fear learning. Furthermore, using a combination of bulk and single-cell RNA-sequencing, we find that, when paired with CFC, HDACi treatment engages synaptic plasticity-promoting gene expression more strongly in the hippocampus, specifically in the dentate gyrus (DG). Finally, using chromatin immunoprecipitation-sequencing (ChIP-seq) of DG neurons, we show that the combined action of HDACi application and conditioning is required to elicit enhancer histone acetylation in pathways that underlie improved memory performance. Together, these results indicate that systemic HDACi administration amplifies brain region-specific processes that are naturally induced by learning.
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17
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Rudzki S. Is PTSD an Evolutionary Survival Adaptation Initiated by Unrestrained Cytokine Signaling and Maintained by Epigenetic Change? Mil Med 2022; 188:usac095. [PMID: 35446412 DOI: 10.1093/milmed/usac095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 03/01/2022] [Accepted: 03/24/2022] [Indexed: 12/22/2022] Open
Abstract
INTRODUCTION Treatment outcomes for PTSD with current psychological therapies are poor, with very few patients achieving sustained symptom remission. A number of authors have identified physiological and immune disturbances in Post Traumatic Stress Disorder (PTSD) patients, but there is no unifying hypothesis that explains the myriad features of the disorder. MATERIALS AND METHODS The medical literature was reviewed over a 6-year period primarily using the medical database PUBMED. RESULTS The literature contains numerous papers that have identified a range of physiological and immune dysfunction in association with PTSD. This paper proposes that unrestrained cytokine signaling induces epigenetic changes that promote an evolutionary survival adaptation, which maintains a defensive PTSD phenotype. The brain can associate immune signaling with past threat and initiate a defensive behavioral response. The sympathetic nervous system is pro-inflammatory, while the parasympathetic nervous system is anti-inflammatory. Prolonged cholinergic withdrawal will promote a chronic inflammatory state. The innate immune cytokine IL-1β has pleiotropic properties and can regulate autonomic, glucocorticoid, and glutamate receptor functions, sleep, memory, and epigenetic enzymes. Changes in epigenetic enzyme activity can potentially alter phenotype and induce an adaptation. Levels of IL-1β correlate with severity and duration of PTSD and PTSD can be prevented by bolus administration of hydrocortisone in acute sepsis, consistent with unrestrained inflammation being a risk factor for PTSD. The nervous and immune systems engage in crosstalk, governed by common receptors. The benefits of currently used psychiatric medication may arise from immune, as well as synaptic, modulation. The psychedelic drugs (3,4-Methylenedioxymethamphetamine (MDMA), psilocybin, and ketamine) have potent immunosuppressive and anti-inflammatory effects on the adaptive immune system, which may contribute to their reported benefit in PTSD. There may be distinct PTSD phenotypes induced by innate and adaptive cytokine signaling. CONCLUSION In order for an organism to survive, it must adapt to its environment. Cytokines signal danger to the brain and can induce epigenetic changes that result in a persistent defensive phenotype. PTSD may be the price individuals pay for the genomic flexibility that promotes adaptation and survival.
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Affiliation(s)
- Stephan Rudzki
- Canberra Sports Medicine, Deakin, Australian Capital Territory 2600, Australia
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18
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Neurogenic Interventions for Fear Memory via Modulation of the Hippocampal Function and Neural Circuits. Int J Mol Sci 2022; 23:ijms23073582. [PMID: 35408943 PMCID: PMC8998417 DOI: 10.3390/ijms23073582] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/22/2022] [Accepted: 03/24/2022] [Indexed: 12/15/2022] Open
Abstract
Fear memory helps animals and humans avoid harm from certain stimuli and coordinate adaptive behavior. However, excessive consolidation of fear memory, caused by the dysfunction of cellular mechanisms and neural circuits in the brain, is responsible for post-traumatic stress disorder and anxiety-related disorders. Dysregulation of specific brain regions and neural circuits, particularly the hippocampus, amygdala, and medial prefrontal cortex, have been demonstrated in patients with these disorders. These regions are involved in learning, memory, consolidation, and extinction. These are also the brain regions where new neurons are generated and are crucial for memory formation and integration. Therefore, these three brain regions and neural circuits have contributed greatly to studies on neural plasticity and structural remodeling in patients with psychiatric disorders. In this review, we provide an understanding of fear memory and its underlying cellular mechanisms and describe how neural circuits are involved in fear memory. Additionally, we discuss therapeutic interventions for these disorders based on their proneurogenic efficacy and the neural circuits involved in fear memory.
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19
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Faucher P, Huguet C, Mons N, Micheau J. Acute pre-learning stress selectively impairs hippocampus-dependent fear memory consolidation: Behavioral and molecular evidence. Neurobiol Learn Mem 2022; 188:107585. [PMID: 35021061 DOI: 10.1016/j.nlm.2022.107585] [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: 07/27/2021] [Revised: 12/22/2021] [Accepted: 01/04/2022] [Indexed: 11/30/2022]
Abstract
Despite compelling evidence that stress or stress-related hormones influence fear memory consolidation processes, the understanding of molecular mechanisms underlying the effects of stress is still fragmentary. The release of corticosterone in response to pre-learning stress exposure has been demonstrated to modulate positively or negatively memory encoding and/or consolidation according to many variables such as stress intensity, the emotional valence of the learned material or the interval between stressful episode and learning experience. Here, we report that contextual but not cued fear memory consolidation was selectively impaired in male mice exposed to a 50 min-period of restraint stress just before the unpaired fear conditioning session. In addition to behavioral impairment, acute stress down-regulated activated/phosphorylated ERK1/2 (pERK1/2) in dorsal hippocampal area CA1 in mice sacrificed 60 min and 9 h after unpaired conditioning. In lateral amygdala, although acute stress by itself increased the level of pERK1/2 it nevertheless blocked the peak of pERK1/2 that was normally observed 15 min after unpaired conditioning. To examine whether stress-induced corticosterone overflow was responsible of these detrimental effects, the corticosterone synthesis inhibitor, metyrapone, was administered 30 min before stress exposure. Metyrapone abrogated the stress-induced contextual fear memory deficits but did not alleviate the effects of stress on pERK1/2 and its downstream target phosphorylated CREB (pCREB) in hippocampus CA1 and lateral amygdala. Collectively, our observations suggest that consolidation of hippocampus-dependent memory and the associated signaling pathway are particularly sensitive to stress. However, behavioral normalization by preventive metyrapone treatment was not accompanied by renormalization of the canonical signaling pathway. A new avenue would be to consider surrogate mechanisms involving proper metyrapone influence on both nongenomic and genomic actions of glucocorticoid receptors.
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Affiliation(s)
- Pierre Faucher
- Université de Bordeaux, CNRS, INCIA, UMR 5287, F-33000 Bordeaux, France
| | - Célia Huguet
- Université de Bordeaux, CNRS, INCIA, UMR 5287, F-33000 Bordeaux, France
| | - Nicole Mons
- Université de Bordeaux, CNRS, INCIA, UMR 5287, F-33000 Bordeaux, France
| | - Jacques Micheau
- Université de Bordeaux, CNRS, INCIA, UMR 5287, F-33000 Bordeaux, France.
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20
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An epigenetic mechanism for over-consolidation of fear memories. Mol Psychiatry 2022; 27:4893-4904. [PMID: 36127428 PMCID: PMC9763112 DOI: 10.1038/s41380-022-01758-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 08/09/2022] [Accepted: 08/18/2022] [Indexed: 01/14/2023]
Abstract
Excessive fear is a hallmark of anxiety disorders, a major cause of disease burden worldwide. Substantial evidence supports a role of prefrontal cortex-amygdala circuits in the regulation of fear and anxiety, but the molecular mechanisms that regulate their activity remain poorly understood. Here, we show that downregulation of the histone methyltransferase PRDM2 in the dorsomedial prefrontal cortex enhances fear expression by modulating fear memory consolidation. We further show that Prdm2 knock-down (KD) in neurons that project from the dorsomedial prefrontal cortex to the basolateral amygdala (dmPFC-BLA) promotes increased fear expression. Prdm2 KD in the dmPFC-BLA circuit also resulted in increased expression of genes involved in synaptogenesis, suggesting that Prdm2 KD modulates consolidation of conditioned fear by modifying synaptic strength at dmPFC-BLA projection targets. Consistent with an enhanced synaptic efficacy, we found that dmPFC Prdm2 KD increased glutamatergic release probability in the BLA and increased the activity of BLA neurons in response to fear-associated cues. Together, our findings provide a new molecular mechanism for excessive fear responses, wherein PRDM2 modulates the dmPFC -BLA circuit through specific transcriptomic changes.
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21
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Yildiz CB, Zimmer-Bensch G. Role of DNMTs in the Brain. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1389:363-394. [DOI: 10.1007/978-3-031-11454-0_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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22
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Ghai M, Kader F. A Review on Epigenetic Inheritance of Experiences in Humans. Biochem Genet 2021; 60:1107-1140. [PMID: 34792705 DOI: 10.1007/s10528-021-10155-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 11/04/2021] [Indexed: 12/13/2022]
Abstract
If genetics defines the inheritance of DNA, epigenetics aims to regulate and make it adaptable. Epigenetic alterations include DNA methylation, chromatin remodelling, post-translational modifications of histone proteins and activity of non-coding RNAs. Several studies, especially in animal models, have reported transgenerational inheritance of epigenetic marks. However, evidence of transgenerational inheritance in humans via germline in the absence of any direct exposure to the driving external stimulus remains controversial. Most of the epimutations exist in relation with genetic variants. The present review looks at intergenerational and transgenerational inheritance in humans, (both father and mother) in response to diet, exposure to chemicals, stress, exercise, and disease status. If not transgenerational, at least intergenerational human studies could help to understand early processes of inheritance. In humans, female and male germline development follow separate paths of epigenetic events and both oocyte and sperm possess their own unique epigenomes. While DNA methylation alterations are reset during epigenetic reprogramming, non-coding RNAs via human sperm provide evidence of being reliable carriers for transgenerational inheritance. Human studies reveal that one mechanism of epigenetic inheritance cannot be applied to the complete human genome. Multiple factors including time, type, and tissue of exposure determine if the modified epigenetic mark could be transmissible and till which generation. Population-specific differences should also be taken into consideration while associating inheritance to an environmental exposure. A longitudinal study targeting one environmental factor, but different population groups should be conducted at a specific geographical location to pinpoint heritable epigenetic changes.
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Affiliation(s)
- Meenu Ghai
- Discipline of Genetics, School of Life Sciences, Westville Campus, University of KwaZulu-Natal, Private Bag X54001, Durban, KwaZulu Natal, South Africa.
| | - Farzeen Kader
- Discipline of Genetics, School of Life Sciences, Westville Campus, University of KwaZulu-Natal, Private Bag X54001, Durban, KwaZulu Natal, South Africa
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23
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The Molecular Biology of Susceptibility to Post-Traumatic Stress Disorder: Highlights of Epigenetics and Epigenomics. Int J Mol Sci 2021; 22:ijms221910743. [PMID: 34639084 PMCID: PMC8509551 DOI: 10.3390/ijms221910743] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/28/2021] [Accepted: 09/29/2021] [Indexed: 12/13/2022] Open
Abstract
Exposure to trauma is one of the most important and prevalent risk factors for mental and physical ill-health. Excessive or prolonged stress exposure increases the risk of a wide variety of mental and physical symptoms. However, people differ strikingly in their susceptibility to develop signs and symptoms of mental illness after traumatic stress. Post-traumatic stress disorder (PTSD) is a debilitating disorder affecting approximately 8% of the world’s population during their lifetime, and typically develops after exposure to a traumatic event. Despite that exposure to potentially traumatizing events occurs in a large proportion of the general population, about 80–90% of trauma-exposed individuals do not develop PTSD, suggesting an inter-individual difference in vulnerability to PTSD. While the biological mechanisms underlying this differential susceptibility are unknown, epigenetic changes have been proposed to underlie the relationship between exposure to traumatic stress and the susceptibility to develop PTSD. Epigenetic mechanisms refer to environmentally sensitive modifications to DNA and RNA molecules that regulate gene transcription without altering the genetic sequence itself. In this review, we provide an overview of various molecular biological, biochemical and physiological alterations in PTSD, focusing on changes at the genomic and epigenomic level. Finally, we will discuss how current knowledge may aid us in early detection and improved management of PTSD patients.
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24
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Abstract
Drug addiction is responsible for millions of deaths per year around the world. Still, its management as a chronic disease is shadowed by misconceptions from the general public. Indeed, drug consumers are often labelled as "weak", "immoral" or "depraved". Consequently, drug addiction is often perceived as an individual problem and not societal. In technical terms, drug addiction is defined as a chronic, relapsing disease resulting from sustained effects of drugs on the brain. Through a better characterisation of the cerebral circuits involved, and the long-term modifications of the brain induced by addictive drugs administrations, first, we might be able to change the way the general public see the patient who is suffering from drug addiction, and second, we might be able to find new treatments to normalise the altered brain homeostasis. In this review, we synthetise the contribution of fundamental research to the understanding drug addiction and its contribution to potential novel therapeutics. Mostly based on drug-induced modifications of synaptic plasticity and epigenetic mechanisms (and their behavioural correlates) and after demonstration of their reversibility, we tried to highlight promising therapeutics. We also underline the specific temporal dynamics and psychosocial aspects of this complex psychiatric disease adding parameters to be considered in clinical trials and paving the way to test new therapeutic venues.
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25
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Gostolupce D, Iordanova MD, Lay BPP. Mechanisms of higher-order learning in the amygdala. Behav Brain Res 2021; 414:113435. [PMID: 34197867 DOI: 10.1016/j.bbr.2021.113435] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 06/17/2021] [Accepted: 06/22/2021] [Indexed: 10/21/2022]
Abstract
Adaptive behaviour is under the potent control of environmental cues. Such cues can acquire value by virtue of their associations with outcomes of motivational significance, be they appetitive or aversive. There are at least two ways through which an environmental cue can acquire value, through first-order and higher-order conditioning. In first-order conditioning, a neutral cue is directly paired with an outcome of motivational significance. In higher-order conditioning, a cue is indirectly associated with motivational events via a directly conditioned first-order stimulus. The present article reviews some of the associations that support learning in first- and higher-order conditioning, as well as the role of the BLA and the molecular mechanisms involved in these two types of learning.
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Affiliation(s)
- Dilara Gostolupce
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, QC, Canada
| | - Mihaela D Iordanova
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, QC, Canada.
| | - Belinda P P Lay
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, QC, Canada
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26
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Van Gils J, Magdinier F, Fergelot P, Lacombe D. Rubinstein-Taybi Syndrome: A Model of Epigenetic Disorder. Genes (Basel) 2021; 12:968. [PMID: 34202860 PMCID: PMC8303114 DOI: 10.3390/genes12070968] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 05/31/2021] [Accepted: 06/16/2021] [Indexed: 12/24/2022] Open
Abstract
The Rubinstein-Taybi syndrome (RSTS) is a rare congenital developmental disorder characterized by a typical facial dysmorphism, distal limb abnormalities, intellectual disability, and many additional phenotypical features. It occurs at between 1/100,000 and 1/125,000 births. Two genes are currently known to cause RSTS, CREBBP and EP300, mutated in around 55% and 8% of clinically diagnosed cases, respectively. To date, 500 pathogenic variants have been reported for the CREBBP gene and 118 for EP300. These two genes encode paralogs acting as lysine acetyltransferase involved in transcriptional regulation and chromatin remodeling with a key role in neuronal plasticity and cognition. Because of the clinical heterogeneity of this syndrome ranging from the typical clinical diagnosis to features overlapping with other Mendelian disorders of the epigenetic machinery, phenotype/genotype correlations remain difficult to establish. In this context, the deciphering of the patho-physiological process underlying these diseases and the definition of a specific episignature will likely improve the diagnostic efficiency but also open novel therapeutic perspectives. This review summarizes the current clinical and molecular knowledge and highlights the epigenetic regulation of RSTS as a model of chromatinopathy.
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Affiliation(s)
- Julien Van Gils
- Reference Center AD SOOR, AnDDI-RARE, INSERM U 1211, Medical Genetics Department, Bordeaux University, Centre Hospitalier Universitaire de Bordeaux, 33076 Bordeaux, France; (P.F.); (D.L.)
| | - Frederique Magdinier
- Marseille Medical Genetics, INSERM U 1251, MMG, Aix Marseille University, 13385 Marseille, France;
| | - Patricia Fergelot
- Reference Center AD SOOR, AnDDI-RARE, INSERM U 1211, Medical Genetics Department, Bordeaux University, Centre Hospitalier Universitaire de Bordeaux, 33076 Bordeaux, France; (P.F.); (D.L.)
| | - Didier Lacombe
- Reference Center AD SOOR, AnDDI-RARE, INSERM U 1211, Medical Genetics Department, Bordeaux University, Centre Hospitalier Universitaire de Bordeaux, 33076 Bordeaux, France; (P.F.); (D.L.)
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27
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Bellver-Sanchis A, Pallàs M, Griñán-Ferré C. The Contribution of Epigenetic Inheritance Processes on Age-Related Cognitive Decline and Alzheimer's Disease. EPIGENOMES 2021; 5:epigenomes5020015. [PMID: 34968302 PMCID: PMC8594669 DOI: 10.3390/epigenomes5020015] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/15/2021] [Accepted: 06/17/2021] [Indexed: 12/15/2022] Open
Abstract
During the last years, epigenetic processes have emerged as important factors for many neurodegenerative diseases, such as Alzheimer’s disease (AD). These complex diseases seem to have a heritable component; however, genome-wide association studies failed to identify the genetic loci involved in the etiology. So, how can these changes be transmitted from one generation to the next? Answering this question would allow us to understand how the environment can affect human populations for multiple generations and explain the high prevalence of neurodegenerative diseases, such as AD. This review pays particular attention to the relationship among epigenetics, cognition, and neurodegeneration across generations, deepening the understanding of the relevance of heritability in neurodegenerative diseases. We highlight some recent examples of EI induced by experiences, focusing on their contribution of processes in learning and memory to point out new targets for therapeutic interventions. Here, we first describe the prominent role of epigenetic factors in memory processing. Then, we briefly discuss aspects of EI. Additionally, we summarize evidence of how epigenetic marks inherited by experience and/or environmental stimuli contribute to cognitive status offspring since better knowledge of EI can provide clues in the appearance and development of age-related cognitive decline and AD.
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28
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Solntseva SV, Nikitin PV, Kozyrev SA, Nikitin VP. Learning against the Background of DNA Methyltransferase Inhibition Leads to the Formation of Memory That Is Resistant to Reactivation and Impairment. Bull Exp Biol Med 2021; 170:288-293. [PMID: 33452638 DOI: 10.1007/s10517-021-05053-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Indexed: 12/31/2022]
Abstract
The involvement of DNA methylation in the mechanisms of formation of conditioned food aversion memory was studied on Helix lucorum snails. The dynamics of aversion formation in snails injected with DNA methyltransferase inhibitor RG108 did not differ from that in control snails. The memory was retained for more than one month after training following RG108 injection and the duration of memory persistence did not differ from that in control animals. However, the characteristics of memory in control and experimental snails differed significantly. In control snails, injections of glutamate NMDA-receptor antagonist or protein synthesis inhibitor before memory retrieval caused disorders in the memory reconsolidation and development of amnesia 2 days after training. By contrast, injections of these substances before retrieval to snails trained against the background of RG108 treatment caused no memory disorders. We hypothesized that inhibition of DNA methylation processes led to the formation of strong memory, not reactivated after retrieval and not transformed into a labile state sensitive to amnesic agents.
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Affiliation(s)
- S V Solntseva
- P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia
| | - P V Nikitin
- P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia.
| | - S A Kozyrev
- P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia
| | - V P Nikitin
- P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia
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29
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Laricchiuta D, Sciamanna G, Gimenez J, Termine A, Fabrizio C, Caioli S, Balsamo F, Panuccio A, De Bardi M, Saba L, Passarello N, Cutuli D, Mattioni A, Zona C, Orlando V, Petrosini L. Optogenetic Stimulation of Prelimbic Pyramidal Neurons Maintains Fear Memories and Modulates Amygdala Pyramidal Neuron Transcriptome. Int J Mol Sci 2021; 22:ijms22020810. [PMID: 33467450 PMCID: PMC7830910 DOI: 10.3390/ijms22020810] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 01/12/2021] [Accepted: 01/12/2021] [Indexed: 12/26/2022] Open
Abstract
Fear extinction requires coordinated neural activity within the amygdala and medial prefrontal cortex (mPFC). Any behavior has a transcriptomic signature that is modified by environmental experiences, and specific genes are involved in functional plasticity and synaptic wiring during fear extinction. Here, we investigated the effects of optogenetic manipulations of prelimbic (PrL) pyramidal neurons and amygdala gene expression to analyze the specific transcriptional pathways associated to adaptive and maladaptive fear extinction. To this aim, transgenic mice were (or not) fear-conditioned and during the extinction phase they received optogenetic (or sham) stimulations over photo-activable PrL pyramidal neurons. At the end of behavioral testing, electrophysiological (neural cellular excitability and Excitatory Post-Synaptic Currents) and morphological (spinogenesis) correlates were evaluated in the PrL pyramidal neurons. Furthermore, transcriptomic cell-specific RNA-analyses (differential gene expression profiling and functional enrichment analyses) were performed in amygdala pyramidal neurons. Our results show that the optogenetic activation of PrL pyramidal neurons in fear-conditioned mice induces fear extinction deficits, reflected in an increase of cellular excitability, excitatory neurotransmission, and spinogenesis of PrL pyramidal neurons, and associated to strong modifications of the transcriptome of amygdala pyramidal neurons. Understanding the electrophysiological, morphological, and transcriptomic architecture of fear extinction may facilitate the comprehension of fear-related disorders.
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Affiliation(s)
- Daniela Laricchiuta
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
- Correspondence:
| | - Giuseppe Sciamanna
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
| | - Juliette Gimenez
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
| | - Andrea Termine
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
- Department of Systems Medicine, Tor Vergata University of Rome, 00133 Rome, Italy;
| | - Carlo Fabrizio
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
- Department of Systems Medicine, Tor Vergata University of Rome, 00133 Rome, Italy;
| | - Silvia Caioli
- Unit of Neurology, IRCCS Neuromed, 86077 Pozzilli, Italy;
| | - Francesca Balsamo
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
| | - Anna Panuccio
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
- Department of Psychology, University “Sapienza” of Rome, 00185 Rome, Italy
| | - Marco De Bardi
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
| | - Luana Saba
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
| | - Noemi Passarello
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
| | - Debora Cutuli
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
- Department of Psychology, University “Sapienza” of Rome, 00185 Rome, Italy
| | - Anna Mattioni
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
| | - Cristina Zona
- Department of Systems Medicine, Tor Vergata University of Rome, 00133 Rome, Italy;
| | - Valerio Orlando
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
- Biological Environmental Science and Engineering Division, KAUST Environmental Epigenetics Program, Thuwal 23955-6900, Saudi Arabia
| | - Laura Petrosini
- Department of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (G.S.); (J.G.); (A.T.); (C.F.); (F.B.); (A.P.); (M.D.B.); (L.S.); (N.P.); (D.C.); (A.M.); (V.O.); (L.P.)
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Navabpour S, Rogers J, McFadden T, Jarome TJ. DNA Double-Strand Breaks Are a Critical Regulator of Fear Memory Reconsolidation. Int J Mol Sci 2020; 21:ijms21238995. [PMID: 33256213 PMCID: PMC7730899 DOI: 10.3390/ijms21238995] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 11/23/2020] [Accepted: 11/23/2020] [Indexed: 11/16/2022] Open
Abstract
Numerous studies have shown that following retrieval, a previously consolidated memory requires increased transcriptional regulation in order to be reconsolidated. Previously, it was reported that histone H3 lysine-4 trimethylation (H3K4me3), a marker of active transcription, is increased in the hippocampus after the retrieval of contextual fear memory. However, it is currently unknown how this epigenetic mark is regulated during the reconsolidation process. Furthermore, though recent evidence suggests that neuronal activity triggers DNA double-strand breaks (DSBs) in some early-response genes, it is currently unknown if DSBs contribute to the reconsolidation of a memory following retrieval. Here, using chromatin immunoprecipitation (ChIP) analyses, we report a significant overlap between DSBs and H3K4me3 in area CA1 of the hippocampus during the reconsolidation process. We found an increase in phosphorylation of histone H2A.X at serine 139 (H2A.XpS139), a marker of DSB, in the Npas4, but not c-fos, promoter region 5 min after retrieval, which correlated with increased H3K4me3 levels, suggesting that the two epigenetic marks may work in concert during the reconsolidation process. Consistent with this, in vivo siRNA-mediated knockdown of topoisomerase II β, the enzyme responsible for DSB, prior to retrieval, reduced Npas4 promoter-specific H2A.XpS139 and H3K4me3 levels and impaired long-term memory, indicating an indispensable role of DSBs in the memory reconsolidation process. Collectively, our data propose a novel mechanism for memory reconsolidation through increases in epigenetic-mediated transcriptional control via DNA double-strand breaks.
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Affiliation(s)
- Shaghayegh Navabpour
- Fralin Biomedical Research Institute, Translational Biology, Medicine & Health, Virginia Polytechnic Institute and State University, Roanoke, VA 24016, USA;
| | - Jessie Rogers
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA;
| | - Taylor McFadden
- Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA;
| | - Timothy J. Jarome
- Fralin Biomedical Research Institute, Translational Biology, Medicine & Health, Virginia Polytechnic Institute and State University, Roanoke, VA 24016, USA;
- Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA;
- School of Neuroscience, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
- Correspondence: ; Tel.: +1-540-231-3520
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Creighton SD, Stefanelli G, Reda A, Zovkic IB. Epigenetic Mechanisms of Learning and Memory: Implications for Aging. Int J Mol Sci 2020; 21:E6918. [PMID: 32967185 PMCID: PMC7554829 DOI: 10.3390/ijms21186918] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 12/15/2022] Open
Abstract
The neuronal epigenome is highly sensitive to external events and its function is vital for producing stable behavioral outcomes, such as the formation of long-lasting memories. The importance of epigenetic regulation in memory is now well established and growing evidence points to altered epigenome function in the aging brain as a contributing factor to age-related memory decline. In this review, we first summarize the typical role of epigenetic factors in memory processing in a healthy young brain, then discuss the aspects of this system that are altered with aging. There is general agreement that many epigenetic marks are modified with aging, but there are still substantial inconsistencies in the precise nature of these changes and their link with memory decline. Here, we discuss the potential source of age-related changes in the epigenome and their implications for therapeutic intervention in age-related cognitive decline.
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Affiliation(s)
- Samantha D. Creighton
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada; (S.D.C.); (G.S.)
| | - Gilda Stefanelli
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada; (S.D.C.); (G.S.)
| | - Anas Reda
- Department of Cell & Systems Biology, University of Toronto, Toronto, ON M5S, Canada;
| | - Iva B. Zovkic
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada; (S.D.C.); (G.S.)
- Department of Cell & Systems Biology, University of Toronto, Toronto, ON M5S, Canada;
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Molecular Mechanisms of Reconsolidation-Dependent Memory Updating. Int J Mol Sci 2020; 21:ijms21186580. [PMID: 32916796 PMCID: PMC7555418 DOI: 10.3390/ijms21186580] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 09/06/2020] [Accepted: 09/07/2020] [Indexed: 12/19/2022] Open
Abstract
Memory is not a stable record of experience, but instead is an ongoing process that allows existing memories to be modified with new information through a reconsolidation-dependent updating process. For a previously stable memory to be updated, the memory must first become labile through a process called destabilization. Destabilization is a protein degradation-dependent process that occurs when new information is presented. Following destabilization, a memory becomes stable again through a protein synthesis-dependent process called restabilization. Much work remains to fully characterize the mechanisms that underlie both destabilization and subsequent restabilization, however. In this article, we briefly review the discovery of reconsolidation as a potential mechanism for memory updating. We then discuss the behavioral paradigms that have been used to identify the molecular mechanisms of reconsolidation-dependent memory updating. Finally, we outline what is known about the molecular mechanisms that support the memory updating process. Understanding the molecular mechanisms underlying reconsolidation-dependent memory updating is an important step toward leveraging this process in a therapeutic setting to modify maladaptive memories and to improve memory when it fails.
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Mohammadi-Farani A, Pourmotabbed A, Ardeshirizadeh Y. Effects of HDAC inhibitors on spatial memory and memory extinction in SPS-induced PTSD rats. Res Pharm Sci 2020; 15:241-248. [PMID: 33088324 PMCID: PMC7540814 DOI: 10.4103/1735-5362.288426] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Revised: 02/06/2020] [Accepted: 02/25/2020] [Indexed: 11/04/2022] Open
Abstract
Background and purpose Neurobiological changes in memory processes seem to play a role in the pathophysiology of post-traumatic stress disorder (PTSD). Memory itself is influenced by PTSD, too. Histone deacetylase inhibitors (HDAIs) have shown promising results in the extinction of fear-related memories in animals and hence they seem to be important for the treatment of PTSD. Data are scarce about the effect of HDAIs in spatial memory formation/extinction in PTSD models. The main goal of the present work is to find the effect of sodium butyrate (NaBu), as an HDAI, on spatial memory and spatial memory extinction in rats exposed to single prolonged stress procedure (SPS). Experimental approach Different doses of NaBu were administered subcutaneously for 7 days in different groups of rats after SPS procedure. Learning, memory, and extinction of memory were evaluated in the Morris water maze test of spatial memory in 6 consecutive days. Findings / Results The results show that NaBu (0.5 mg/kg) alleviates impaired learning and memory in SPS rats. It also facilitates the extinction of newly formed memory in the animals. Conclusion and implications Our data suggest that the administration of HDAIs after a traumatic experience can prevent the aversive effects of SPS on spatial memory. It also reinforces the notion that extinction of spatial memory involves the same or similar brain circuitry that is involved in the extinction of fear memories in PTSD patients.
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Affiliation(s)
- Ahmad Mohammadi-Farani
- Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, I.R. Iran.,Department of Pharmacology, Toxicology and Medical Services, School of Pharmacy, Kermanshah University of Medical Sciences, Kermanshah, I.R. Iran
| | - Ali Pourmotabbed
- Department of Physiology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, I.R. Iran
| | - Yazdan Ardeshirizadeh
- Student Research Committee, Kermanshah University of Medical Sciences, Kermanshah, I.R. Iran
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Tu PS, Lin ECY, Chen HW, Chen SW, Lin TA, Gau JP, Chang YI. The extracellular signal-regulated kinase 1/2 modulates the intracellular localization of DNA methyltransferase 3A to regulate erythrocytic differentiation. Am J Transl Res 2020; 12:1016-1030. [PMID: 32269731 PMCID: PMC7137067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Accepted: 03/15/2020] [Indexed: 06/11/2023]
Abstract
DNA methylation, catalyzed by DNA methyltransferases (DNMTs), is a heritable epigenetic mark, participating in numerous physiological processes. DNMT3A is of particular relevance to hematopoietic differentiation, because DNMT3A mutations are strongly related to hematopoietic malignancies. Additionally, DNMT3A deficiency has been reported to increase the hematopoietic stem cell pool by limiting their differentiation. Our previous study demonstrated that complete loss of DNMT3A resulted in anemia, while DNMT3A haploinsufficiency caused an elevated population of erythrocytes in the content of oncogenic KRAS. Since erythropoiesis is tightly regulated via the erythropoietin (EPO)-mediated RAS-RAF-MEK-ERK1/2 pathway, the question arises whether DNMT3A cooperates with RAS signaling to modulate erythropoiesis. Human leukemia cell lines were used, with differentiation capabilities towards megakaryocyte and erythroid lineages. Overexpression of DNMT3A was found to enhance erythrocytic differentiation of K562 cells, while DNMT3A knockdown suppressed differentiation. Furthermore, higher DNMT3A expression was detected in late-stage mouse erythroblasts along with the DNMT3A translocation to the nucleus. Further studies demonstrated that both ERK1/2-DNMT3A interaction and serine-255 phosphorylation in DNMT3A led to DNMT3A translocation into the nucleus, and modulated erythrocytic differentiation. Our results not only explore the critical role of DNMT3A in erythropoiesis, but also provide a new insight into ERK1/2-DNMT3A interaction in the hematopoietic system.
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Affiliation(s)
- Po-Shu Tu
- Department and Institute of Physiology, National Yang-Ming UniversityTaipei 11221, Taiwan
| | - Eric Chang-Yi Lin
- Department and Institute of Physiology, National Yang-Ming UniversityTaipei 11221, Taiwan
| | - Hsiao-Wen Chen
- Department and Institute of Physiology, National Yang-Ming UniversityTaipei 11221, Taiwan
| | - Shuoh-Wen Chen
- Department and Institute of Physiology, National Yang-Ming UniversityTaipei 11221, Taiwan
| | - Ting-An Lin
- Department and Institute of Physiology, National Yang-Ming UniversityTaipei 11221, Taiwan
- Division of Hematology and Oncology, Department of Medicine, Taipei Veterans General HospitalTaipei 11217, Taiwan
| | - Jyh-Pyng Gau
- Faculty of Medicine, National Yang-Ming UniversityTaipei 11221, Taiwan
- Division of Hematology and Oncology, Department of Medicine, Taipei Veterans General HospitalTaipei 11217, Taiwan
| | - Yuan-I Chang
- Department and Institute of Physiology, National Yang-Ming UniversityTaipei 11221, Taiwan
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Martínez-Pacheco H, Picazo O, López-Torres A, Morin JP, Castro-Cerritos KV, Zepeda RC, Roldán-Roldán G. Biochemical and Behavioral Characterization of IN14, a New Inhibitor of HDACs with Antidepressant-Like Properties. Biomolecules 2020; 10:biom10020299. [PMID: 32075023 PMCID: PMC7072255 DOI: 10.3390/biom10020299] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 02/06/2020] [Accepted: 02/12/2020] [Indexed: 12/27/2022] Open
Abstract
Evidence suggests that histone deacetylases (HDACs) inhibitors could be used as an effective treatment for some psychiatric and neurological conditions such as depression, anxiety and age-related cognitive decline. However, non-specific HDAC inhibiting compounds have a clear disadvantage regarding their efficacy and safety, thus the need to develop more selective ones. The present study evaluated the toxicity, the capacity to inhibit HDAC activity and antidepressant-like activity of three recently described class I HDAC inhibitors IN01, IN04 and IN14, using A. salina toxicity test, in vitro fluorometric HDAC activity assay and forced-swimming test, respectively. Our data show that IN14 possesses a better profile than the other two. Therefore, the pro-cognitive and antidepressant effects of IN14 were evaluated. In the forced-swimming test model of depression, intraperitoneal administration of IN14 (100 mg/Kg/day) for five days decreased immobility, a putative marker of behavioral despair, significantly more than tricyclic antidepressant desipramine, while also increasing climbing behavior, a putative marker of motivational behavior. On the other hand, IN14 left the retention latency in the elevated T-maze unaltered. These results suggest that novel HDAC class I inhibitor IN14 may represent a promising new antidepressant with low toxicity and encourages further studies on this compound.
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Affiliation(s)
- Heidy Martínez-Pacheco
- Laboratorio de Neurobiología Conductual, Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico; (H.M.-P.); (J.-P.M.)
| | - Ofir Picazo
- Sección de Estudios de Posgrado e Investigación de la Escuela Superior de Medicina del Instituto Politécnico Nacional, Plan de San Luis y Salvador Díaz Mirón s/n, Casco de Santo Tomás, Ciudad de México 11340, Mexico;
| | - Adolfo López-Torres
- Instituto de Química Aplicada, Universidad del Papaloapan, Campus Tuxtepec, Circuito Central 200, Parque Industrial, Tuxtepec, Oaxaca 68301, Mexico (K.V.C.-C.)
| | - Jean-Pascal Morin
- Laboratorio de Neurobiología Conductual, Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico; (H.M.-P.); (J.-P.M.)
| | - Karla Viridiana Castro-Cerritos
- Instituto de Química Aplicada, Universidad del Papaloapan, Campus Tuxtepec, Circuito Central 200, Parque Industrial, Tuxtepec, Oaxaca 68301, Mexico (K.V.C.-C.)
| | - Rossana Citlali Zepeda
- Centro de Investigaciones Biomédicas, Universidad Veracruzana. Av. Dr. Luis Castelazo Ayala s/n. Col., Industrial Ánimas, Xalapa, Veracruz 91190, Mexico;
| | - Gabriel Roldán-Roldán
- Laboratorio de Neurobiología Conductual, Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico; (H.M.-P.); (J.-P.M.)
- Correspondence: ; Tel.: +52-5556-232364
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36
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Monsey MS, Ruiz SG, Taylor JR. Regulation of Garcinol on Histone Acetylation in the Amygdala and on the Reconsolidation of a Cocaine-Associated Memory. Front Behav Neurosci 2020; 13:281. [PMID: 31998092 PMCID: PMC6961612 DOI: 10.3389/fnbeh.2019.00281] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 12/11/2019] [Indexed: 12/15/2022] Open
Abstract
Exposure to drug-related cues often disrupts abstinence from cocaine use by triggering memories of drug effects, leading to craving and possible relapse. One prospective method of treatment is weakening cocaine-associated memories via impairment of memory reconsolidation. Previous experiments have shown that systemic injection of the amnestic agent garcinol impairs the reconsolidation of cocaine-cue memories in a temporally constrained, cue-specific, and persistent manner. Here, we investigated garcinol’s effect on cocaine-cue memory reconsolidation when administered to the lateral nucleus of the amygdala (LA), as well as its epigenetic activity following systemic garcinol administration and also when given in conjunction with trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor. Rats received 12 days of cocaine self-administration training during which time an active lever press resulted in an i.v. cocaine infusion that was concurrently paired with the presentation of a light/tone cue. After 8 days of lever extinction, rats received a memory reactivation session followed by a cue-induced reinstatement test. Intra-LA garcinol following memory reactivation significantly impaired reconsolidation only if the memory was reactivated. Additional studies revealed a significant reduction in histone H3 K27 acetylation and reduced expression of the immediate-early genes Arc and Egr-1 in the LA. When administered alone, TSA enhanced the reinstatement of a cocaine-cue memory, an effect that was prevented when garcinol was concurrently administered. These data indicate the LA is a key structure responsive to garcinol, suggest that one of garcinol’s mechanisms of action is through the reduction of memory-related gene expression in the LA, implicate changes in histone acetylation in memory reconsolidation, and support garcinol as a potential therapeutic tool for sustaining abstinence.
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Affiliation(s)
- Melissa S Monsey
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, United States
| | - Sonia G Ruiz
- Department of Psychology, Yale University, New Haven, CT, United States
| | - Jane R Taylor
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, United States.,Department of Psychology, Yale University, New Haven, CT, United States.,Department of Neuroscience, Yale University, New Haven, CT, United States
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Nikitin V, Solntseva S, Kozyrev S, Nikitin P. Long-term memory consolidation or reconsolidation impairment induces amnesia with key characteristics that are similar to key learning characteristics. Neurosci Biobehav Rev 2020; 108:542-558. [DOI: 10.1016/j.neubiorev.2019.12.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 09/16/2019] [Accepted: 12/03/2019] [Indexed: 02/07/2023]
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38
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Montagud-Romero S, Cantacorps L, Valverde O. Histone deacetylases inhibitor trichostatin A reverses anxiety-like symptoms and memory impairments induced by maternal binge alcohol drinking in mice. J Psychopharmacol 2019; 33:1573-1587. [PMID: 31294671 DOI: 10.1177/0269881119857208] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Alcohol exposure during development has detrimental effects, including a wide range of physical, cognitive and neurobehavioural anomalies known as foetal alcohol spectrum disorders. However, alcohol consumption among pregnant woman is an ongoing latent health problem. AIM In the present study, the effects of trichostatin A (TSA) on emotional and cognitive impairments caused by prenatal and lactational alcohol exposure were assessed. TSA is an inhibitor of class I and II histone deacetylases enzymes (HDAC), and for that, HDAC4 activity was determined. We also evaluated mechanisms underlying the behavioural effects observed, including the expression of brain-derived neurotrophic factor (BDNF) in discrete brain regions and newly differentiated neurons in the dentate gyrus (DG). METHODS C57BL/6 female pregnant mice were used, with limited access to a 20% v/v alcohol solution as a procedure to model binge alcohol drinking during gestation and lactation. Male offspring were treated with TSA during the postnatal days (PD28-35) and behaviourally evaluated (PD36-55). RESULTS Early alcohol exposure mice presented increased anxiogenic-like responses and memory deterioration - effects that were partially reversed with TSA. Early alcohol exposure produces a decrease in BDNF levels in the hippocampus (HPC) and prefrontal cortex, a reduction of neurogenesis in the DG and increased activity levels of the HDAC4 in the HPC. CONCLUSIONS Such findings support the participation of HDAC enzymes in cognitive and emotional alterations induced by binge alcohol consumption during gestation and lactation and would indicate potential benefits of HDAC inhibitors for some aspects of foetal alcohol spectrum disorders.
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Affiliation(s)
- Sandra Montagud-Romero
- Neurobiology of Behaviour Research Group (GReNeC-NeuroBio), Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Lídia Cantacorps
- Neurobiology of Behaviour Research Group (GReNeC-NeuroBio), Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Olga Valverde
- Neurobiology of Behaviour Research Group (GReNeC-NeuroBio), Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain.,IMIM-Hospital del Mar Medical Research Institute, Neurosciences Programme, Barcelona, Spain
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39
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Uniyal A, Singh R, Akhtar A, Dhaliwal J, Kuhad A, Sah SP. Pharmacological rewriting of fear memories: A beacon for post-traumatic stress disorder. Eur J Pharmacol 2019; 870:172824. [PMID: 31778672 DOI: 10.1016/j.ejphar.2019.172824] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Revised: 11/13/2019] [Accepted: 11/22/2019] [Indexed: 01/08/2023]
Abstract
Post-traumatic stress disorder (PTSD) is a psychopathological response that develops after exposure to an extreme life-threatening traumatic event. Its prevalence ranges from 0.5% to 14.5% worldwide. Due to the complex pathophysiology of PTSD, currently available treatment approaches are associated with high chances of failure, thus further research to identify better pharmacotherapeutic approaches is needed. The traumatic event associated with fear memories plays an important role in the development of PTSD and could be considered as the main culprit. PTSD patient feels frightened in a safe environment as the memories of the traumatic event are revisited. Neurocircuit involving normal processing of fear memories get disturbed in PTSD hence making a fear memory to remain to dominate even after years of trauma. Persistence of fear memories could be explained by acquisition, re-(consolidation) and extinction triad as all of these processes have been widely explored in preclinical as well as clinical studies and set a therapeutic platform for fear memory associated disorders. This review focuses on neurocircuit and pathophysiology of PTSD in context to fear memories and pharmacological targeting of fear memory for the management of PTSD.
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Affiliation(s)
- Ankit Uniyal
- Pharmacology Division, University Institute of Pharmaceutical Sciences, UGC-CAS, Panjab University, Chandigarh, 160014, India; Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (B.H.U.) Varanasi, 221005, Uttar Pradesh, India
| | - Raghunath Singh
- Pharmacology Division, University Institute of Pharmaceutical Sciences, UGC-CAS, Panjab University, Chandigarh, 160014, India
| | - Ansab Akhtar
- Pharmacology Division, University Institute of Pharmaceutical Sciences, UGC-CAS, Panjab University, Chandigarh, 160014, India
| | - Jatinder Dhaliwal
- Pharmacology Division, University Institute of Pharmaceutical Sciences, UGC-CAS, Panjab University, Chandigarh, 160014, India
| | - Anurag Kuhad
- Pharmacology Division, University Institute of Pharmaceutical Sciences, UGC-CAS, Panjab University, Chandigarh, 160014, India
| | - Sangeeta Pilkhwal Sah
- Pharmacology Division, University Institute of Pharmaceutical Sciences, UGC-CAS, Panjab University, Chandigarh, 160014, India.
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40
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Topuz RD, Gunduz O, Tastekin E, Karadag CH. Effects of hippocampal histone acetylation and HDAC inhibition on spatial learning and memory in the Morris water maze in rats. Fundam Clin Pharmacol 2019; 34:222-228. [PMID: 31617237 DOI: 10.1111/fcp.12512] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 10/11/2019] [Accepted: 10/14/2019] [Indexed: 01/31/2023]
Abstract
In recent years, it has been pointed out that epigenetic changes affect learning and memory formation. Particularly, it has been shown that histone acetylation and DNA methylation work in concert to regulate learning and memory formation. We aimed to examine whether acetylation of H2B within the rat hippocampus alters by trainings in the Morris water maze test. Male, 2-3 months old, Sprague Dawley rats were trained in Morris water maze task. Animals were given four trials per day for five consecutive days to locate a hidden platform. On the sixth day, the platform was removed and the animals were swum for 60 s. The effects of sodium butyrate, histone deacetylase inhibitor, were tested on normal and scopolamine-induced memory-impaired rats. The histone deacetylase inhibitor, sodium butyrate, increased histone H2B acetylation in normal rats. Sodium butyrate had no effect on learning and memory performance of normal rats; however, it partially ameliorated learning and memory disruption induced by scopolamine. So, the histone deacetylase inhibitors can be new treatment agent for cognitive disorders.
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Affiliation(s)
- Ruhan Deniz Topuz
- Department of Medical Pharmacology, Faculty of Medicine, Trakya University, 22030, Edirne, Turkey
| | - Ozgur Gunduz
- Department of Medical Pharmacology, Faculty of Medicine, Trakya University, 22030, Edirne, Turkey
| | - Ebru Tastekin
- Department of Pathology, Faculty of Medicine, Trakya University, 22030, Edirne, Turkey
| | - Cetin Hakan Karadag
- Department of Medical Pharmacology, Faculty of Medicine, Trakya University, 22030, Edirne, Turkey
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Williams AR, Kim ES, Lattal KM. Behavioral and immunohistochemical characterization of rapid reconditioning following extinction of contextual fear. Learn Mem 2019; 26:1-16. [PMID: 31527183 PMCID: PMC6749931 DOI: 10.1101/lm.048439.118] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 07/12/2019] [Indexed: 01/27/2023]
Abstract
A fundamental property of extinction is that the behavior that is suppressed during extinction can be unmasked through a number of postextinction procedures. Of the commonly studied unmasking procedures (spontaneous recovery, reinstatement, contextual renewal, and rapid reacquisition), rapid reacquisition is the only approach that allows a direct comparison between the impact of a conditioning trial before or after extinction. Thus, it provides an opportunity to evaluate the ways in which extinction changes a subsequent learning experience. In five experiments, we investigate the behavioral and neurobiological mechanisms of postextinction reconditioning. We show that rapid reconditioning of unsignaled contextual fear after extinction in male Long-Evans rats is associative and not affected by the number or duration of extinction sessions that we examined. We then evaluate c-Fos expression and histone acetylation (H4K8) in the hippocampus, amygdala, prefrontal cortex, and bed nucleus of the stria terminalis. We find that in general, initial conditioning has a stronger impact on c-Fos expression and acetylation than does reconditioning after extinction. We discuss implications of these results for theories of extinction and the neurobiology of conditioning and extinction.
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Affiliation(s)
- Amy R Williams
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - Earnest S Kim
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - K Matthew Lattal
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon 97239, USA
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Williams-Spooner MJ, Westbrook RF, Holmes NM. The Conditions under Which Consolidation of Serial-Order Conditioned Fear Requires De Novo Protein Synthesis in the Basolateral Amygdala Complex. J Neurosci 2019; 39:7357-7368. [PMID: 31341027 PMCID: PMC6759024 DOI: 10.1523/jneurosci.0768-19.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 06/02/2019] [Accepted: 07/14/2019] [Indexed: 11/21/2022] Open
Abstract
Consolidation of conditioned fear to a stimulus (S1) paired with shock requires de novo protein synthesis in the basolateral amygdala complex (BLA), whereas consolidation of conditioned fear to a stimulus (S2) paired with the fear-eliciting S1 requires DNA methylation but not de novo protein synthesis in the BLA. The present experiments merged these protocols by exposing rats to pairings of a serial S2-S1 compound and shock to examine if/when protein synthesis in the BLA is required to consolidate fear to S2. Rats received a BLA infusion of the protein synthesis inhibitor, cycloheximide, immediately after the S2-S1-shock session and were subsequently tested with S2. The infusion disrupted consolidation of fear to S2 when there had been no prior training of S1 (Experiment 1), the prior training had consisted of unpaired presentations of S1 and shock (Experiment 4), or in pairings of S1 and sucrose (Experiment 5). Consolidation of fear to S2 was unaffected by the infusion of cycloheximide but was disrupted by the DNA methyltransferase inhibitor, 5-AZA, when S1 had been previously fear-conditioned (Experiments 2a, 2b, and 3). These findings imply that what has already been learned about S1 determines the BLA processes that consolidate fear to S2. The already-fear-conditioned S1 blocks the S2-shock association that otherwise forms (and whose consolidation requires de novo protein synthesis in the BLA) while simultaneously acting as a learned source of danger for its S2 associate (whose consolidation requires DNA methylation but not de novo protein synthesis in the BLA).SIGNIFICANCE STATEMENT Protein synthesis is widely thought to be crucial for consolidating new learning into stable memories, including the consolidation of conditioned fear memories in the basolateral amygdala complex (BLA). However, our data provide clear evidence that the requirement for protein synthesis to consolidate conditioned fear in the BLA depends on an animal's previous training history, and the type of learning that is consolidated. Further, within the BLA, our data show that DNA methylation, and not protein synthesis, is necessary to consolidate higher-order conditioned fear, indicating that epigenetic mechanisms may provide a more fundamental mnemonic substrate.
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Affiliation(s)
| | - R Frederick Westbrook
- School of Psychology, University of New South Wales, Sydney, 2052 New South Wales, Australia
| | - Nathan M Holmes
- School of Psychology, University of New South Wales, Sydney, 2052 New South Wales, Australia
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Siddiqui SA, Singh S, Ugale R, Ranjan V, Kanojia R, Saha S, Tripathy S, Kumar S, Mehrotra S, Modi DR, Prakash A. Regulation of HDAC1 and HDAC2 during consolidation and extinction of fear memory. Brain Res Bull 2019; 150:86-101. [PMID: 31108155 DOI: 10.1016/j.brainresbull.2019.05.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 04/02/2019] [Accepted: 05/15/2019] [Indexed: 01/03/2023]
Abstract
Histone deacetylases (HDACs) regulate gene expression epigenetically through synchronized removal of acetyl groups from histones required towards memory consolidation. Moreover, dysregulated epigenetic machinery during fear or extinction learning may result in altered expression of some of these genes and result in Post Traumatic Stress Disorder (PTSD). In the present study, region-specific expression of Histone deacetylase 1 (HDAC1) and Histone deacetylase 2 (HDAC2) was correlated to the acetylation of histones H3 and H4 and the resultant conditioned response, in rats undergone fear and extinction learning. The neuronal activation, histone acetylation at H3/H4 and expression of HDAC1/HDAC2 in centrolateral amygdala (CeL) and centromedial amygdala (CeM) of central Amygdala (CeA) and prelimbic (PL) and infralimbic (IL) of Prefrontal cortex (PFC) were found to be associated in a differential manner following fear and extinction learning. Moreover in CeM, the main output of the fear circuitry, the level of HDAC1 was down-regulated following conditioning and up-regulated following extinction as opposed to which HDAC2 was down-regulated in CeM following conditioning but not following extinction. Furthermore, in CeL the HDAC1 was upregulated and HDAC2 was downregulated following conditioning and extinction. This has important implications in speculating of the role of HDACs in fear memory consolidation and its extinction.
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Affiliation(s)
| | - Sanjay Singh
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Lucknow, India
| | - Rajesh Ugale
- Department of Pharmaceutical Sciences, RTM Nagpur University, Nagpur, India
| | - Vandana Ranjan
- Department of Biochemistry, RML University, Faizabad, India
| | - Rohit Kanojia
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Lucknow, India
| | - Sudipta Saha
- Department of Pharmaceutical Science, Babasaheb Bhimrao Ambedkar University, Lucknow, India
| | - Sukanya Tripathy
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Lucknow, India
| | - Shiv Kumar
- Department of Biochemistry, University of Lucknow, Lucknow, India
| | - Sudhir Mehrotra
- Department of Biochemistry, University of Lucknow, Lucknow, India
| | - Dinesh Raj Modi
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Lucknow, India
| | - Anand Prakash
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Lucknow, India; Department of Biotech, Mahatma Gandhi Central University, Motihari, Bihar, India.
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Smolen P, Baxter DA, Byrne JH. How can memories last for days, years, or a lifetime? Proposed mechanisms for maintaining synaptic potentiation and memory. ACTA ACUST UNITED AC 2019; 26:133-150. [PMID: 30992383 PMCID: PMC6478248 DOI: 10.1101/lm.049395.119] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Accepted: 03/12/2019] [Indexed: 01/24/2023]
Abstract
With memory encoding reliant on persistent changes in the properties of synapses, a key question is how can memories be maintained from days to months or a lifetime given molecular turnover? It is likely that positive feedback loops are necessary to persistently maintain the strength of synapses that participate in encoding. Such feedback may occur within signal-transduction cascades and/or the regulation of translation, and it may occur within specific subcellular compartments or within neuronal networks. Not surprisingly, numerous positive feedback loops have been proposed. Some posited loops operate at the level of biochemical signal-transduction cascades, such as persistent activation of Ca2+/calmodulin kinase II (CaMKII) or protein kinase Mζ. Another level consists of feedback loops involving transcriptional, epigenetic and translational pathways, and autocrine actions of growth factors such as BDNF. Finally, at the neuronal network level, recurrent reactivation of cell assemblies encoding memories is likely to be essential for late maintenance of memory. These levels are not isolated, but linked by shared components of feedback loops. Here, we review characteristics of some commonly discussed feedback loops proposed to underlie the maintenance of memory and long-term synaptic plasticity, assess evidence for and against their necessity, and suggest experiments that could further delineate the dynamics of these feedback loops. We also discuss crosstalk between proposed loops, and ways in which such interaction can facilitate the rapidity and robustness of memory formation and storage.
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Affiliation(s)
- Paul Smolen
- Department of Neurobiology and Anatomy, W. M. Keck Center for the Neurobiology of Learning and Memory, McGovern Medical School of the University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Douglas A Baxter
- Department of Neurobiology and Anatomy, W. M. Keck Center for the Neurobiology of Learning and Memory, McGovern Medical School of the University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - John H Byrne
- Department of Neurobiology and Anatomy, W. M. Keck Center for the Neurobiology of Learning and Memory, McGovern Medical School of the University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
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Brandwein NJ, Nguyen PV. A requirement for epigenetic modifications during noradrenergic stabilization of heterosynaptic LTP in the hippocampus. Neurobiol Learn Mem 2019; 161:72-82. [PMID: 30930287 DOI: 10.1016/j.nlm.2019.03.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 03/22/2019] [Accepted: 03/27/2019] [Indexed: 12/31/2022]
Abstract
Beta-adrenergic receptor (b-AR) activation by noradrenaline (NA) enhances memory formation and long-term potentiation (LTP), a form of synaptic plasticity characterized by an activity-dependent increase in synaptic strength. LTP is believed to be a cellular mechanism for contextual learning and memory. In the mammalian hippocampus, LTP can be observed at multiple synaptic pathways after strong stimulation of a single synaptic pathway. This heterosynaptic LTP is believed to involve synaptic tagging of active synapses and capture of plasticity-related proteins that enable heterosynaptic transfer of persistent potentiation. These processes may permit distinct neural pathways to associate information transmitted by separate, but convergent, synaptic inputs. We had previously shown that transcription and epigenetic modifications were necessary for stabilization of homosynaptic LTP. However, it is unclear whether transfer of LTP to a second, heterosynaptic pathway involves b-ARs signalling to the nucleus. Using electrophysiologic recordings in area CA1 of murine hippocampal slices, we show here that pharmacologically inhibiting b-AR activation, transcription, DNA methyltransferase or histone acetyltransferase activation, prevents stabilization of heterosynaptic LTP. Our data suggest that noradrenergic stabilization of heterosynaptic ("tagged") LTP requires not only transcription, but specifically, DNA methylation and histone acetylation. NA promotes stable heterosynaptic plasticity through engagement of nuclear processes that may contribute to prompt consolidation of short-term memories into resilient long-term memories under conditions when the brain's noradrenergic system is recruited.
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Affiliation(s)
- N J Brandwein
- Department of Physiology, University of Alberta School of Medicine, Edmonton, Alberta T6G 2H7, Canada
| | - P V Nguyen
- Department of Physiology, University of Alberta School of Medicine, Edmonton, Alberta T6G 2H7, Canada.
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Li H, Yu F, Sun X, Xu L, Miu J, Xiao P. Dihydromyricetin ameliorates memory impairment induced by acute sleep deprivation. Eur J Pharmacol 2019; 853:220-228. [PMID: 30876981 DOI: 10.1016/j.ejphar.2019.03.014] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Revised: 03/07/2019] [Accepted: 03/11/2019] [Indexed: 01/15/2023]
Abstract
Dihydromyricetin (DHM), the major bioactive flavonoid ingredient extracted from the leaves of Ampelopsis grossedentata (Hand.-Mazz) W.T. Wang displays multiple pharmacological activities, including oxidation resistance, anti-tumour properties and free radical scavenging capacities. However, the role of DHM in sleep deprivation (SD)-induced memory impairments and its underlying molecular mechanisms are unclear. The aim of the present study was to evaluate the effects of DHM on oxidative stress and its role in ameliorating memory impairment induced by acute SD. DHM (100, 50, 25 mg/kg) and melatonin (10 mg/kg) were administered to mice via oral gavage. The open field test was used to evaluate motor function. Spatial learning and memory were assessed using the Morris water maze task. Malondialdehyde, glutathione, and glutathione disulfide levels, as well as superoxide dismutase enzyme activity, were assessed to determine the level of oxidative stress. In addition, we employed quantitative real-time PCR assays to examine the gene expression of 29 key proteins, including protein kinase A (PKA), cAMP response element binding protein (CREB), and adcy1. The levels of proteins including those of GABABRS, GABAARα5, GluR1, BDNF and PSD95, were detected by western blotting. The results showed that DHM significantly attenuated SD-induced spatial learning and memory impairments (P < 0.01). The possible underlying mechanisms of DHM may be attributed to its ability to reduce oxidative stress and restore synaptic plasticity.
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Affiliation(s)
- Hongxiang Li
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, 151 Malianwa North Road, Beijing 100193, China; Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, 151 Malianwa North Road, Beijing 100193, China.
| | - Fan Yu
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, 151 Malianwa North Road, Beijing 100193, China; Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, 151 Malianwa North Road, Beijing 100193, China.
| | - Xiaoyuan Sun
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, 151 Malianwa North Road, Beijing 100193, China; Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, 151 Malianwa North Road, Beijing 100193, China.
| | - Lijia Xu
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, 151 Malianwa North Road, Beijing 100193, China; Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, 151 Malianwa North Road, Beijing 100193, China.
| | - Jianhua Miu
- Guangxi Institute of Medicinal Plant Development, Nanning, 189 Changgang Road, Nanning 520023, China.
| | - Peigen Xiao
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, 151 Malianwa North Road, Beijing 100193, China; Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, 151 Malianwa North Road, Beijing 100193, China.
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Abstract
In the past few decades, the field of neuroepigenetics has investigated how the brain encodes information to form long-lasting memories that lead to stable changes in behaviour. Activity-dependent molecular mechanisms, including, but not limited to, histone modification, DNA methylation and nucleosome remodelling, dynamically regulate the gene expression required for memory formation. Recently, the field has begun to examine how a learning experience is integrated at the level of both chromatin structure and synaptic physiology. Here, we provide an overview of key established epigenetic mechanisms that are important for memory formation. We explore how epigenetic mechanisms give rise to stable alterations in neuronal function by modifying synaptic structure and function, and highlight studies that demonstrate how manipulating epigenetic mechanisms may push the boundaries of memory.
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Affiliation(s)
- Rianne R Campbell
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, Center for Addiction Neuroscience, Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, USA
| | - Marcelo A Wood
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, Center for Addiction Neuroscience, Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, USA.
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48
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Chua GNL, Wassarman KL, Sun H, Alp JA, Jarczyk EI, Kuzio NJ, Bennett MJ, Malachowsky BG, Kruse M, Kennedy AJ. Cytosine-Based TET Enzyme Inhibitors. ACS Med Chem Lett 2019; 10:180-185. [PMID: 30783500 DOI: 10.1021/acsmedchemlett.8b00474] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 01/31/2019] [Indexed: 01/01/2023] Open
Abstract
DNA methylation is known as the prima donna epigenetic mark for its critical role in regulating local gene transcription. Changes in the landscape of DNA methylation across the genome occur during cellular transition, such as differentiation and altered neuronal plasticity, and become dysregulated in disease states such as cancer. The TET family of enzymes is known to be responsible for catalyzing the reverse process that is DNA demethylation by recognizing 5-methylcytosine and oxidizing the methyl group via an Fe(II)/alpha-ketoglutarate-dependent mechanism. Here, we describe the design, synthesis, and evaluation of novel cytosine-based TET enzyme inhibitors, a class of small molecule probes previously underdeveloped but broadly desired in the field of epigenetics. We identify a promising cytosine-based lead compound, Bobcat339, that has mid-μM inhibitor activity against TET1 and TET2, but does not inhibit the DNA methyltransferase, DNMT3a. In silico modeling of the TET enzyme active site is used to rationalize the activity of Bobcat339 and other cytosine-based inhibitors. These new molecular tools will be useful to the field of epigenetics and serve as a starting point for new therapeutics that target DNA methylation and gene transcription.
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Affiliation(s)
- Gabriella N. L. Chua
- Department of Chemistry and Biochemistry, Bates College, 2 Andrews Road, Lewiston, Maine 04240, United States
| | - Kelly L. Wassarman
- Department of Chemistry and Biochemistry, Bates College, 2 Andrews Road, Lewiston, Maine 04240, United States
| | - Haoyu Sun
- Department of Chemistry and Biochemistry, Bates College, 2 Andrews Road, Lewiston, Maine 04240, United States
| | - Joseph A. Alp
- Department of Chemistry and Biochemistry, Bates College, 2 Andrews Road, Lewiston, Maine 04240, United States
| | - Emma I. Jarczyk
- Department of Chemistry and Biochemistry, Bates College, 2 Andrews Road, Lewiston, Maine 04240, United States
| | - Nathanael J. Kuzio
- Department of Chemistry and Biochemistry, Bates College, 2 Andrews Road, Lewiston, Maine 04240, United States
| | - Michael J. Bennett
- Department of Chemistry and Biochemistry, Bates College, 2 Andrews Road, Lewiston, Maine 04240, United States
| | - Beth G. Malachowsky
- Department of Chemistry and Biochemistry, Bates College, 2 Andrews Road, Lewiston, Maine 04240, United States
| | - Martin Kruse
- Department of Biology and Program in Neuroscience, Bates College, 44 Campus Avenue, Lewiston, Maine 04240, United States
| | - Andrew J. Kennedy
- Department of Chemistry and Biochemistry, Bates College, 2 Andrews Road, Lewiston, Maine 04240, United States
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Mao Q, Wu S, Gu X, Du S, Mo K, Sun L, Cao J, Bekker A, Chen L, Tao YX. DNMT3a-triggered downregulation of K 2p 1.1 gene in primary sensory neurons contributes to paclitaxel-induced neuropathic pain. Int J Cancer 2019; 145:2122-2134. [PMID: 30684388 DOI: 10.1002/ijc.32155] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 12/18/2018] [Accepted: 01/21/2019] [Indexed: 12/26/2022]
Abstract
Antineoplastic drugs induce dramatic transcriptional changes in dorsal root ganglion (DRG) neurons, which may contribute to chemotherapy-induced neuropathic pain. K2p 1.1 controls neuronal excitability by setting the resting membrane potential. Here, we report that systemic injection of the chemotherapy agent paclitaxel time-dependently downregulates the expression of K 2p 1.1 mRNA and its coding K2p 1.1 protein in the DRG neurons. Rescuing this downregulation mitigates the development and maintenance of paclitaxel-induced mechanical allodynia and heat hyperalgesia. Conversely, in the absence of paclitaxel administration, mimicking this downregulation decreases outward potassium current and increases excitability in the DRG neurons, leading to the enhanced responses to mechanical and heat stimuli. Mechanically, the downregulation of DRG K 2p 1.1 mRNA is attributed to paclitaxel-induced increase in DRG DNMT3a, as blocking this increase reverses the paclitaxel-induced the decrease of DRG K2p 1.1 and mimicking this increase reduces DRG K2p 1.1 expression. In addition, paclitaxel injection increases the binding of DNMT3a to the K 2p 1.1 gene promoter region and elevates the level of DNA methylation within this region in the DRG. These findings suggest that DNMT3a-triggered downregulation of DRG K2p 1.1 may contribute to chemotherapy-induced neuropathic pain.
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Affiliation(s)
- Qingxiang Mao
- Department of Anesthesiology, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ.,Department of Anesthesiology, Daping Hospital, Institute of Surgery Research, Third Military Medical University (Army Medical University), Chongqing, China
| | - Shaogen Wu
- Department of Anesthesiology, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ
| | - Xiyao Gu
- Department of Anesthesiology, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ
| | - Shibin Du
- Department of Anesthesiology, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ
| | - Kai Mo
- Department of Anesthesiology, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ
| | - Linlin Sun
- Department of Anesthesiology, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ
| | - Jing Cao
- Department of Anesthesiology, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ.,Neuroscience Research Institute, Zhengzhou University Academy of Medical Sciences, Zhengzhou, Henan, China
| | - Alex Bekker
- Department of Anesthesiology, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ
| | - Liyong Chen
- Department of Anesthesiology, Daping Hospital, Institute of Surgery Research, Third Military Medical University (Army Medical University), Chongqing, China
| | - Yuan-Xiang Tao
- Department of Anesthesiology, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ
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Sah A, Sotnikov S, Kharitonova M, Schmuckermair C, Diepold RP, Landgraf R, Whittle N, Singewald N. Epigenetic Mechanisms Within the Cingulate Cortex Regulate Innate Anxiety-Like Behavior. Int J Neuropsychopharmacol 2019; 22:317-328. [PMID: 30668714 PMCID: PMC6441131 DOI: 10.1093/ijnp/pyz004] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 01/11/2019] [Accepted: 01/14/2019] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Pathological anxiety originates from a complex interplay of genetic predisposition and environmental factors, acting via epigenetic mechanisms. Epigenetic processes that can counteract detrimental genetic risk towards innate high anxiety are not well characterized. METHODS We used female mouse lines of selectively bred high (HAB)- vs low (LAB)-innate anxiety-related behavior and performed select environmental and pharmacological manipulations to alter anxiety levels as well as brain-specific manipulations and immunohistochemistry to investigate neuronal mechanisms associated with alterations in anxiety-related behavior. RESULTS Inborn hyperanxiety of high anxiety-like phenotypes was effectively reduced by environmental enrichment exposure. c-Fos mapping revealed that hyperanxiety in high anxiety-like phenotypes was associated with blunted challenge-induced neuronal activation in the cingulate-cortex, which was normalized by environmental enrichment. Relating this finding with epigenetic modifications, we found that high anxiety-like phenotypes (compared with low-innate anxiety phenotypes) showed reduced acetylation in the hypoactivated cingulate-cortex neurons following a mild emotional challenge, which again was normalized by environmental enrichment. Paralleling the findings using environmental enrichment, systemic administration of histone-deacetylase-inhibitor MS-275 elicited an anxiolytic-like effect, which was correlated with increased acetylated-histone-3 levels within cingulate-cortex. Finally, as a proof-of-principle, local MS-275 injection into cingulate-cortex rescued enhanced innate anxiety and increased acetylated-histone-3 within the cingulate-cortex, suggesting this epigenetic mark as a biomarker for treatment success. CONCLUSIONS Taken together, the present findings provide the first causal evidence that the attenuation of high innate anxiety-like behavior via environmental/pharmacological manipulations is epigenetically mediated via acetylation changes within the cingulate-cortex. Finally, histone-3 specific histone-deacetylase-inhibitor could be of therapeutic importance in anxiety disorders.
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Affiliation(s)
- Anupam Sah
- Department of Pharmacology and Toxicology, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
| | | | - Maria Kharitonova
- Department of Pharmacology and Toxicology, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
| | - Claudia Schmuckermair
- Department of Pharmacology and Toxicology, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
| | | | | | - Nigel Whittle
- Department of Pharmacology and Toxicology, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
| | - Nicolas Singewald
- Department of Pharmacology and Toxicology, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria,Correspondence: Nicolas Singewald, PhD, Department of Pharmacology and Toxicology, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80–82/III, A-6020 Innsbruck, Austria ()
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