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Dubey H, Dubey A, Gulati K, Ray A. S-nitrosoglutathione modulates HDAC2 and BDNF levels in the brain and improves cognitive deficits in experimental model of Alzheimer's disease in rats. Int J Neurosci 2024; 134:777-785. [PMID: 36408590 DOI: 10.1080/00207454.2022.2150190] [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: 02/24/2022] [Revised: 11/02/2022] [Accepted: 11/10/2022] [Indexed: 11/22/2022]
Abstract
AIM Alzheimer's disease (AD) is a neurodegenerative disorder which is characterized by cognitive deficits and abnormal memory formation. Histone acetylation is essential for hippocampal memory formation and improving the cognitive deficits, and histone deacetylase 2 (HDAC2) is increased in the hippocampus of AD patients. The present study evaluated the effects of the nitric oxide (NO) mimetics, L-arginine and the nitrosothiol NO donor, s-nitrosoglutathione (GSNO), on memory and brain HDAC2 levels in experimental animal model of sporadic Alzheimer's disease (sAD). METHODS AD was induced experimentally in rats by intracerebroventricular injection of streptozotocin (STZ, 3mg/kg). The effects of NO mimetics, GSNO and L-arginine, were assessed on STZ induced cognitive deficits in the Morris water maze (MWM) test, and, following this, the hippocampal homogenates were assayed for amyloid-β, brain derived neurotropic factor (BDNF) and HDAC2 levels. The neurobehavioral and biochemical data of the drug treated groups were compared with those of experimental control group. RESULTS The results showed that icv-STZ induced cognitive deficits were differentially attenuated by GSNO (50µg/kg) and, to a lesser extent, L-arginine (100mg/kg) with improvement in the spatial learning tasks in MWM test. These behavioral changes were associated with decreased levels of biochemical markers viz. amyloid β, BDNF and HDAC2 levels in hippocampus. CONCLUSIONS It is inferred that NO donors like GSNO could influence AD pathophysiology via epigenetic modification of HDAC2 inhibition.
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Affiliation(s)
- Harikesh Dubey
- Department of Pharmacology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
- Institute for Quantitative Health Sciences and Engineering, Michigan State University, East Lansing, MI, USA
| | - Anamika Dubey
- Department of Pharmacology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Kavita Gulati
- Department of Pharmacology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Arunabha Ray
- Department of Pharmacology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
- Department of Pharmacology, Hamdard Institute of Medical Sciences and Research, Hamdard University, New Delhi, India
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2
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Xu D, Liu J, Meng S, Sun M, Chen Y, Hong Y. Isoflurane-induced neuroinflammation and NKCC1/KCC2 dysregulation result in long-term cognitive disorder in neonatal mice. BMC Anesthesiol 2024; 24:200. [PMID: 38840092 PMCID: PMC11151488 DOI: 10.1186/s12871-024-02587-6] [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: 03/12/2024] [Accepted: 05/29/2024] [Indexed: 06/07/2024] Open
Abstract
BACKGROUND The inhalational anesthetic isoflurane is commonly utilized in clinical practice, particularly in the field of pediatric anesthesia. Research has demonstrated its capacity to induce neuroinflammation and long-term behavioral disorders; however, the underlying mechanism remains unclear [1]. The cation-chloride cotransporters Na+-K+-2Cl--1 (NKCC1) and K+-2Cl--2 (KCC2) play a pivotal role in regulating neuronal responses to gamma-aminobutyric acid (GABA) [2]. Imbalances in NKCC1/KCC2 can disrupt GABA neurotransmission, potentially leading to neural circuit hyperexcitability and reduced inhibition following neonatal exposure to anesthesia [3]. Therefore, this study postulates that anesthetics have the potential to dysregulate NKCC1 and/or KCC2 during brain development. METHODS We administered 1.5% isoflurane anesthesia to neonatal rats for a duration of 4 h at postnatal day 7 (PND7). Anxiety levels were assessed using the open field test at PND28, while cognitive function was evaluated using the Morris water maze test between PND31 and PND34. Protein levels of NKCC1, KCC2, BDNF, and phosphorylated ERK (P-ERK) in the hippocampus were measured through Western blotting analysis. Pro-inflammatory cytokines IL-1β, IL-6, and TNF-α were quantified using ELISA. RESULTS We observed a decrease in locomotion trajectories within the central region and a significantly shorter total distance in the ISO group compared to CON pups, indicating that isoflurane induces anxiety-like behavior. In the Morris water maze (MWM) test, rats exposed to isoflurane exhibited prolonged escape latency onto the platform. Additionally, isoflurane administration resulted in reduced time spent crossing in the MWM experiment at PND34, suggesting long-term impairment of memory function. Furthermore, we found that isoflurane triggered activation of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α; downregulated KCC2/BDNF/P-ERK expression; and increased the NKCC1/KCC2 ratio in the hippocampus of PND7 rats. Bumetadine (NKCC1 specific inhibitors) reversed cognitive damage and effective disorder induced by isoflurane in neonatal rats by inhibiting TNF-α activation, normalizing IL-6 and IL-1β levels, restoring KCC2 expression levels as well as BDNF and ERK signaling pathways. Based on these findings, it can be speculated that BDNF, P-ERK, IL-1β, IL-6 and TNF - α may act downstream of the NKCC1/KCC2 pathway. CONCLUSIONS Our findings provide evidence that isoflurane administration in neonatal rats leads to persistent cognitive deficits through dysregulation of the Cation-Chloride Cotransporters NKCC1 and KCC2, BDNF, p-ERK proteins, as well as neuroinflammatory processes.
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Affiliation(s)
- Dongni Xu
- Department of Anesthesiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 Yanjiang West Road, Guangzhou, 510120, China
| | - Jiayi Liu
- Department of Anesthesiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 Yanjiang West Road, Guangzhou, 510120, China
| | - Shiyu Meng
- Department of Anesthesiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 Yanjiang West Road, Guangzhou, 510120, China
| | - Meixian Sun
- The Eighth People's Hospital of Qingdao, Qingdao, Shandong Province, China
| | - Yuqing Chen
- Department of Anesthesiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 Yanjiang West Road, Guangzhou, 510120, China.
| | - Yu Hong
- Department of Anesthesiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 Yanjiang West Road, Guangzhou, 510120, China.
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Basavarajappa BS, Subbanna S. Unlocking the epigenetic symphony: histone acetylation's impact on neurobehavioral change in neurodegenerative disorders. Epigenomics 2024; 16:331-358. [PMID: 38321930 PMCID: PMC10910622 DOI: 10.2217/epi-2023-0428] [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: 12/04/2023] [Accepted: 01/23/2024] [Indexed: 02/08/2024] Open
Abstract
Recent genomics and epigenetic advances have empowered the exploration of DNA/RNA methylation and histone modifications crucial for gene expression in response to stress, aging and disease. Interest in understanding neuronal plasticity's epigenetic mechanisms, influencing brain rewiring amid development, aging and neurodegenerative disorders, continues to grow. Histone acetylation dysregulation, a commonality in diverse brain disorders, has become a therapeutic focus. Histone acetyltransferases and histone deacetylases have emerged as promising targets for neurodegenerative disorder treatment. This review delves into histone acetylation regulation, potential therapies and future perspectives for disorders like Alzheimer's, Parkinson's and Huntington's. Exploring genetic-environmental interplay through models and studies reveals molecular changes, behavioral insights and early intervention possibilities targeting the epigenome in at-risk individuals.
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Affiliation(s)
- Balapal S Basavarajappa
- Center for Dementia Research, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
- Molecular Imaging & Neuropathology Area, New York State Psychiatric Institute, NY 10032, USA
- Department of Psychiatry, Columbia University Irving Medical Center, NY 10032, USA
- Department of Psychiatry, New York University Langone Medical Center, NY 10016, USA
| | - Shivakumar Subbanna
- Center for Dementia Research, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
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Paniri A, Hosseini MM, Akhavan-Niaki H. Alzheimer's Disease-Related Epigenetic Changes: Novel Therapeutic Targets. Mol Neurobiol 2024; 61:1282-1317. [PMID: 37700216 DOI: 10.1007/s12035-023-03626-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 08/30/2023] [Indexed: 09/14/2023]
Abstract
Aging is a significant risk factor for Alzheimer's disease (AD), although the precise mechanism and molecular basis of AD are not yet fully understood. Epigenetic mechanisms, such as DNA methylation and hydroxymethylation, mitochondrial DNA methylation, histone modifications, and non-coding RNAs (ncRNAs), play a role in regulating gene expression related to neuron plasticity and integrity, which are closely associated with learning and memory development. This review describes the impact of dynamic and reversible epigenetic modifications and factors on memory and plasticity throughout life, emphasizing their potential as target for therapeutic intervention in AD. Additionally, we present insight from postmortem and animal studies on abnormal epigenetics regulation in AD, as well as current strategies aiming at targeting these factors in the context of AD therapy.
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Affiliation(s)
- Alireza Paniri
- Genetics Department, Faculty of Medicine, Babol University of Medical Sciences, Babol, Iran
- Zoonoses Research Center, Pasteur Institute of Iran, Amol, Iran
| | | | - Haleh Akhavan-Niaki
- Genetics Department, Faculty of Medicine, Babol University of Medical Sciences, Babol, Iran.
- Zoonoses Research Center, Pasteur Institute of Iran, Amol, Iran.
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5
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Mir FA, Amanullah A, Jain BP, Hyderi Z, Gautam A. Neuroepigenetics of ageing and neurodegeneration-associated dementia: An updated review. Ageing Res Rev 2023; 91:102067. [PMID: 37689143 DOI: 10.1016/j.arr.2023.102067] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 09/01/2023] [Accepted: 09/06/2023] [Indexed: 09/11/2023]
Abstract
Gene expression is tremendously altered in the brain during memory acquisition, recall, and forgetfulness. However, non-genetic factors, including environmental elements, epigenetic changes, and lifestyle, have grabbed significant attention in recent years regarding the etiology of neurodegenerative diseases (NDD) and age-associated dementia. Epigenetic modifications are essential in regulating gene expression in all living organisms in a DNA sequence-independent manner. The genes implicated in ageing and NDD-related memory disorders are epigenetically regulated by processes such as DNA methylation, histone acetylation as well as messenger RNA editing machinery. The physiological and optimal state of the epigenome, especially within the CNS of humans, plays an intricate role in helping us adjust to the changing environment, and alterations in it cause many brain disorders, but the mechanisms behind it still need to be well understood. When fully understood, these epigenetic landscapes could act as vital targets for pharmacogenetic rescue strategies for treating several diseases, including neurodegeneration- and age-induced dementia. Keeping this objective in mind, this updated review summarises the epigenetic changes associated with age and neurodegeneration-associated dementia.
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Affiliation(s)
- Fayaz Ahmad Mir
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | | | | | - Zeeshan Hyderi
- Department of Biotechnology, Alagappa University, Karaikudi, India
| | - Akash Gautam
- Centre for Neural and Cognitive Sciences, University of Hyderabad, Hyderabad, India.
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6
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Arutjunyan AV, Milyutina YP, Shcherbitskaia AD, Kerkeshko GO, Zalozniaia IV. Epigenetic Mechanisms Involved in the Effects of Maternal Hyperhomocysteinemia on the Functional State of Placenta and Nervous System Plasticity in the Offspring. BIOCHEMISTRY. BIOKHIMIIA 2023; 88:435-456. [PMID: 37080931 DOI: 10.1134/s0006297923040016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/22/2023]
Abstract
According to modern view, susceptibility to diseases, specifically to cognitive and neuropsychiatric disorders, can form during embryonic development. Adverse factors affecting mother during the pregnancy increase the risk of developing pathologies. Despite the association between elevated maternal blood homocysteine (Hcy) and fetal brain impairments, as well as cognitive deficits in the offspring, the role of brain plasticity in the development of these pathologies remains poorly studied. Here, we review the data on the negative impact of hyperhomocysteinemia (HHcy) on the neural plasticity, in particular, its possible influence on the offspring brain plasticity through epigenetic mechanisms, such as changes in intracellular methylation potential, activity of DNA methyltransferases, DNA methylation, histone modifications, and microRNA expression in brain cells. Since placenta plays a key role in the transport of nutrients and transmission of signals from mother to fetus, its dysfunction due to aberrant epigenetic regulation can affect the development of fetal CNS. The review also presents the data on the impact of maternal HHcy on the epigenetic regulation in the placenta. The data presented in the review are not only interesting from purely scientific point of view, but can help in understanding the role of HHcy and epigenetic mechanisms in the pathogenesis of diseases, such as pregnancy pathologies resulting in the delayed development of fetal brain, cognitive impairments in the offspring during childhood, and neuropsychiatric and neurodegenerative disorders later in life, as well as in the search for approaches for their prevention using neuroprotectors.
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Affiliation(s)
- Alexander V Arutjunyan
- Ott Research Institute of Obstetrics, Gynecology and Reproductive Medicine, St. Petersburg, 199034, Russia.
- St. Petersburg Institute of Bioregulation and Gerontology, St. Petersburg, 197110, Russia
| | - Yulia P Milyutina
- Ott Research Institute of Obstetrics, Gynecology and Reproductive Medicine, St. Petersburg, 199034, Russia
- St. Petersburg State Pediatric Medical University, St. Petersburg, 194100, Russia
| | - Anastasia D Shcherbitskaia
- Ott Research Institute of Obstetrics, Gynecology and Reproductive Medicine, St. Petersburg, 199034, Russia
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, Saint Petersburg, 194223, Russia
| | - Gleb O Kerkeshko
- Ott Research Institute of Obstetrics, Gynecology and Reproductive Medicine, St. Petersburg, 199034, Russia
- St. Petersburg Institute of Bioregulation and Gerontology, St. Petersburg, 197110, Russia
| | - Irina V Zalozniaia
- Ott Research Institute of Obstetrics, Gynecology and Reproductive Medicine, St. Petersburg, 199034, Russia
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7
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Maity S, Abbaspour R, Nahabedian D, Connor SA. Norepinephrine, beyond the Synapse: Coordinating Epigenetic Codes for Memory. Int J Mol Sci 2022; 23:ijms23179916. [PMID: 36077313 PMCID: PMC9456295 DOI: 10.3390/ijms23179916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 08/19/2022] [Accepted: 08/21/2022] [Indexed: 11/16/2022] Open
Abstract
The noradrenergic system is implicated in neuropathologies contributing to major disorders of the memory, including post-traumatic stress disorder and Alzheimer’s disease. Determining the impact of norepinephrine on cellular function and plasticity is thus essential for making inroads into our understanding of these brain conditions, while expanding our capacity for treating them. Norepinephrine is a neuromodulator within the mammalian central nervous system which plays important roles in cognition and associated synaptic plasticity. Specifically, norepinephrine regulates the formation of memory through the stimulation of β-ARs, increasing the dynamic range of synaptic modifiability. The mechanisms through which NE influences neural circuit function have been extended to the level of the epigenome. This review focuses on recent insights into how the noradrenergic recruitment of epigenetic modifications, including DNA methylation and post-translational modification of histones, contribute to homo- and heterosynaptic plasticity. These advances will be placed in the context of synaptic changes associated with memory formation and linked to brain disorders and neurotherapeutic applications.
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Affiliation(s)
- Sabyasachi Maity
- Department of Physiology, Neuroscience, and Behavioral Sciences, St. George’s University School of Medicine, True Blue FZ818, Grenada
| | - Raman Abbaspour
- Department of Biology, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
| | - David Nahabedian
- The Center for Biomedical Visualization, Department of Anatomical Sciences, St. George’s University School of Medicine, True Blue FZ818, Grenada
| | - Steven A. Connor
- Department of Biology, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
- Correspondence: ; Tel.: +1-(416)-736-2100 (ext. 33803)
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8
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Leung HW, Foo G, VanDongen A. Arc Regulates Transcription of Genes for Plasticity, Excitability and Alzheimer’s Disease. Biomedicines 2022; 10:biomedicines10081946. [PMID: 36009494 PMCID: PMC9405677 DOI: 10.3390/biomedicines10081946] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/21/2022] [Accepted: 07/25/2022] [Indexed: 02/06/2023] Open
Abstract
The immediate early gene Arc is a master regulator of synaptic function and a critical determinant of memory consolidation. Here, we show that Arc interacts with dynamic chromatin and closely associates with histone markers for active enhancers and transcription in cultured rat hippocampal neurons. Both these histone modifications, H3K27Ac and H3K9Ac, have recently been shown to be upregulated in late-onset Alzheimer’s disease (AD). When Arc induction by pharmacological network activation was prevented using a short hairpin RNA, the expression profile was altered for over 1900 genes, which included genes associated with synaptic function, neuronal plasticity, intrinsic excitability, and signalling pathways. Interestingly, about 100 Arc-dependent genes are associated with the pathophysiology of AD. When endogenous Arc expression was induced in HEK293T cells, the transcription of many neuronal genes was increased, suggesting that Arc can control expression in the absence of activated signalling pathways. Taken together, these data establish Arc as a master regulator of neuronal activity-dependent gene expression and suggest that it plays a significant role in the pathophysiology of AD.
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Affiliation(s)
| | - Gabriel Foo
- Duke-NUS Medical School, Singapore 169857, Singapore
| | - Antonius VanDongen
- Duke-NUS Medical School, Singapore 169857, Singapore
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27710, USA
- Correspondence:
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9
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Epigenetic Mechanisms in Memory and Cognitive Decline Associated with Aging and Alzheimer's Disease. Int J Mol Sci 2021; 22:ijms222212280. [PMID: 34830163 PMCID: PMC8618067 DOI: 10.3390/ijms222212280] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/10/2021] [Accepted: 11/11/2021] [Indexed: 12/21/2022] Open
Abstract
Epigenetic mechanisms, which include DNA methylation, a variety of post-translational modifications of histone proteins (acetylation, phosphorylation, methylation, ubiquitination, sumoylation, serotonylation, dopaminylation), chromatin remodeling enzymes, and long non-coding RNAs, are robust regulators of activity-dependent changes in gene transcription. In the brain, many of these epigenetic modifications have been widely implicated in synaptic plasticity and memory formation. Dysregulation of epigenetic mechanisms has been reported in the aged brain and is associated with or contributes to memory decline across the lifespan. Furthermore, alterations in the epigenome have been reported in neurodegenerative disorders, including Alzheimer’s disease. Here, we review the diverse types of epigenetic modifications and their role in activity- and learning-dependent synaptic plasticity. We then discuss how these mechanisms become dysregulated across the lifespan and contribute to memory loss with age and in Alzheimer’s disease. Collectively, the evidence reviewed here strongly supports a role for diverse epigenetic mechanisms in memory formation, aging, and neurodegeneration in the brain.
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10
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Akbarabadi A, Sadat-Shirazi MS, Kabbaj M, Nouri Zadeh-Tehrani S, Khalifeh S, Pirri F, Zarrindast MR. Effects of Morphine and Maternal Care on Behaviors and Protein Expression of Male Offspring. Neuroscience 2021; 466:58-76. [PMID: 33915201 DOI: 10.1016/j.neuroscience.2021.04.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 04/14/2021] [Accepted: 04/15/2021] [Indexed: 01/26/2023]
Abstract
Genes and environment interact during development to alter gene expression and behavior. Parental morphine exposure before conception has devastating effects on the offspring. In the present study, we evaluated the role of maternal care in the intergenerational effect of maternal morphine exposure. Female rats received morphine or saline for ten days and were drugfree for another ten days. Thereafter, they were allowed to mate with drug-naïve male rats. When pups were born, they were cross-fostered to assess the contribution of maternal care versus morphine effects on the offspring. Adult male offspring were examined for anxiety-like behavior, spatial memory, and obsessive-compulsive-like behavior. To determine the mechanisms underlying the observed behavioral changes, protein levels of acetylated histone H3, BDNF, Trk-B, NMDA subunits, p-CREB, and 5-HT3R were measured in the brain. Our results indicate that maternal caregiving is impaired in morphine-abstinent mothers. Interestingly, maternal care behaviors were also affected in drug-naïve mothers that raised offspring of morphine-exposed mothers. In addition, the offspring of morphine abstinent and non-drug dependent mothers, when raised by morphine abstinent mothers, exhibited more anxiety, obsessive-compulsive behaviors and impaired spatial memory. These altered behaviors were associated with alterations in the levels of the above-mentioned proteins. These data illustrate the intergenerational effects of maternal morphine exposure on offspring behaviors. Moreover, exposure to morphine before gestation not only affects maternal care and offspring behavior, but also has negative consequences on behaviors and protein expression in adoptive mothers of affected offspring.
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Affiliation(s)
- Ardeshir Akbarabadi
- Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Mohamed Kabbaj
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL 32306-1270, United States; Program of Neuroscience, Florida State University, Tallahassee, FL 32306-1270, United States
| | | | - Solmaz Khalifeh
- Cognitive and Neuroscience Research Center (CNRC), Tehran Medical Sciences, Amir-Almomenin Hospital, Islamic Azad University, Tehran, Iran
| | - Fardad Pirri
- Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad-Reza Zarrindast
- Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, Tehran, Iran; Cognitive and Neuroscience Research Center (CNRC), Tehran Medical Sciences, Amir-Almomenin Hospital, Islamic Azad University, Tehran, Iran; Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Endocrinology and Metabolism Research Institute, Tehran University of Medical Science, Tehran, Iran.
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11
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Mews P, Calipari ES, Day J, Lobo MK, Bredy T, Abel T. From Circuits to Chromatin: The Emerging Role of Epigenetics in Mental Health. J Neurosci 2021; 41:873-882. [PMID: 33446519 PMCID: PMC7880276 DOI: 10.1523/jneurosci.1649-20.2020] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 12/19/2020] [Accepted: 12/22/2020] [Indexed: 02/01/2023] Open
Abstract
A central goal of neuroscience research is to understand how experiences modify brain circuits to guide future adaptive behavior. In response to environmental stimuli, neural circuit activity engages gene regulatory mechanisms within each cell. This activity-dependent gene expression is governed, in part, by epigenetic processes that can produce persistent changes in both neural circuits and the epigenome itself. The complex interplay between circuit activity and neuronal gene regulation is vital to learning and memory, and, when disrupted, is linked to debilitating psychiatric conditions, such as substance use disorder. To develop clinical treatments, it is paramount to advance our understanding of how neural circuits and the epigenome cooperate to produce behavioral adaptation. Here, we discuss how new genetic tools, used to manipulate neural circuits and chromatin, have enabled the discovery of epigenetic processes that bring about long-lasting changes in behavior relevant to mental health and disease.
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Affiliation(s)
- Philipp Mews
- Friedman Brain Institute, Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York 10129
| | - Erin S Calipari
- Departments of Pharmacology, Molecular Physiology and Biophysics, Psychiatry and Behavioral Sciences; Vanderbilt Center for Addiction Research; Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee 37323
| | - Jeremy Day
- Department of Neurobiology, McKnight Brain Institute, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Mary Kay Lobo
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Timothy Bredy
- Queensland Brain Institute, University of Queensland, Brisbane, 4072, Australia
| | - Ted Abel
- Department of Neuroscience and Pharmacology, Iowa Neuroscience Institute, University of Iowa, Iowa City, Iowa 52242
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Sadat-Shirazi MS, Asgari P, Mahboubi S, Nouri Zadeh-Tehrani S, Ashabi G, Rohbani K, Sabzevari S, Soltani H, Khalifeh S, Zarrindast MR. Effect of morphine exposure on novel object memory of the offspring: The role of histone H3 and ΔFosB. Brain Res Bull 2020; 156:141-149. [PMID: 31958477 DOI: 10.1016/j.brainresbull.2020.01.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 12/19/2019] [Accepted: 01/14/2020] [Indexed: 01/09/2023]
Abstract
It has been demonstrated that alteration in histone acetylation in the regions of the brain involved in the reward which may have an important role in morphine addiction. It is well established that epigenetic changes prior to birth influence the function and development of the brain. The current study was designed to evaluate changes in novel object memory, histone acetylation and ΔFosB in the brain of the offspring of morphine-withdrawn parents. Male and female Wistar rats received morphine orally for 21 following days. After ten days of abstinent, they were prepared for mating. The male offspring of the first parturition were euthanized on postnatal days 5, 21, 30 and 60. The novel object recognition (NOR) test was performed on adult male offspring. The amount of acetylated histone H3 and ΔFosB were evaluated in the prefrontal cortex (PFC) and hippocampus using western blotting. Obtained results indicated that the discrimination index in the NOR test was decreased in the offspring of morphine-withdrawn parents as compared with morphine-naïve offspring. In addition, the level of acetylated histone H3 was decreased in the PFC and hippocampus in the offspring of morphine-withdrawn parents during lifetime (postnatal days 5, 21, 30 and 60). In the case of ΔFosB, it also decreased in these regions in the morphine-withdrawn offspring. These results demonstrated that parental morphine exposure affects NOR memory, and decreased the level of histone H3 acetylation and ΔFosB in the PFC and hippocampus. Taken together, the effect of morphine might be transmitted to the next generation even after stop consuming morphine.
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Affiliation(s)
| | - Pardis Asgari
- Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, Tehran, Iran
| | - Sarah Mahboubi
- Department of Neuroscience and Addiction Studies, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Ghorbangol Ashabi
- Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Kiyana Rohbani
- Department of Molecular and Cellular Sciences, Faculty of Advanced Sciences and Technology, Pharmaceutical Sciences Branch, Islamic Azad University, Tehran, Iran
| | - Saba Sabzevari
- Department of Molecular and Cellular Sciences, Faculty of Advanced Sciences and Technology, Pharmaceutical Sciences Branch, Islamic Azad University, Tehran, Iran
| | - Haniyeh Soltani
- Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, Tehran, Iran
| | - Solmaz Khalifeh
- Cognitive and Neuroscience Research Center (CNRC), Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Mohammad-Reza Zarrindast
- Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, Tehran, Iran; Cognitive and Neuroscience Research Center (CNRC), Tehran Medical Sciences, Islamic Azad University, Tehran, Iran; Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Endocrinology and Metabolism Research Institute, Tehran University of Medical Science, Tehran, Iran.
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López AJ, Siciliano CA, Calipari ES. Activity-Dependent Epigenetic Remodeling in Cocaine Use Disorder. Handb Exp Pharmacol 2019; 258:231-263. [PMID: 31628597 DOI: 10.1007/164_2019_257] [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] [Indexed: 12/27/2022]
Abstract
Substance use disorder (SUD) is a behavioral disorder characterized by cycles of abstinence, drug seeking, and relapse. SUD is characterized by aberrant learning processes which develop after repeated exposure to drugs of abuse. At the core of this phenotype is the persistence of symptoms, such as craving and relapse to drug seeking, long after the cessation of drug use. The neural basis of these behavioral changes has been linked to dysfunction in neural circuits across the brain; however, the molecular drivers that allow for these changes to persist beyond the lifespan of any individual protein remain opaque. Epigenetic adaptations - where DNA is modified to increase or decrease the probability of gene expression at key genes - have been identified as a mechanism underlying the long-lasting nature of drug-seeking behavior. Thus, to understand SUD, it is critical to define the interplay between neuronal activation and longer-term changes in transcription and epigenetic remodeling and define their role in addictive behaviors. In this review, we discuss the current understanding of drug-induced changes to circuit function, recent discoveries in epigenetic mechanisms that mediate these changes, and, ultimately, how these adaptations drive the persistent nature of relapse, with emphasis on adaptations in models of cocaine use disorder. Understanding the complex interplay between epigenetic gene regulation and circuit activity will be critical in elucidating the neural mechanisms underlying SUD. This, with the advent of novel genetic-based techniques, will allow for the generation of novel therapeutic avenues to improve treatment outcomes in SUD.
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Affiliation(s)
- Alberto J López
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA.,Vanderbilt Center for Addiction Research, Vanderbilt University School of Medicine, Nashville, TN, USA.,Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Cody A Siciliano
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA.,Vanderbilt Center for Addiction Research, Vanderbilt University School of Medicine, Nashville, TN, USA.,Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Erin S Calipari
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA. .,Vanderbilt Center for Addiction Research, Vanderbilt University School of Medicine, Nashville, TN, USA. .,Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, TN, USA. .,Department of Molecular Physiology and Biophysics, Vanderbilt Institute for Infection, Immunology, and Infection, Vanderbilt University School of Medicine, Nashville, TN, USA. .,Department of Psychiatry and Behavioral Sciences, Vanderbilt Institute for Infection, Immunology, and Infection, Vanderbilt University School of Medicine, Nashville, TN, USA.
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14
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Abstract
This commentary reviews the concept of experience-dependent epigenetic modifications in the CNS as a core mechanism underlying individuality and individuation at the behavioral level. I use the term individuation to refer to the underlying neurobiological processes that result in individuality, with the discussion focusing on individuality of cognitive, emotional, and behavioral repertoire. The review describes recent work supporting the concept of neuroepigenetic mechanisms underlying individuation, possible roles of transgenerational effects, and implications for precision medicine.
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Affiliation(s)
- J David Sweatt
- Department of Pharmacology, Vanderbilt University, Nashville, TN
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15
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Dubey H, Gulati K, Ray A. Recent studies on cellular and molecular mechanisms in Alzheimer’s disease: focus on epigenetic factors and histone deacetylase. Rev Neurosci 2018; 29:241-260. [DOI: 10.1515/revneuro-2017-0049] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 08/28/2017] [Indexed: 01/06/2023]
Abstract
AbstractAlzheimer’s disease (AD) is one of the most common neurodegenerative disorders mainly affecting elderly people. It is characterized by progressive loss of memory and cognitive function. More than 95% of AD cases are related to sporadic or late-onset AD (LOAD). The etiology of LOAD is still unclear. It has been reported that environmental factors and epigenetic alterations play a significant role in AD pathogenesis. Furthermore, recently, genome-wide association studies (GWAS) identified 10 novel risk genes:ABCA7,APOE,BIN1,CD2AP,CD33,CLU,CR1,MS4A6A,MS4A4E, andPICALM, which play an important role for LOAD. In this review, the therapeutic approaches of AD by epigenetic modifications have been discussed. Nowadays, HDAC inhibitors have clinically proven its activity for epigenetic modifications. Furthermore, we try to establish the relationship between HDAC inhibitors and above mentioned LOAD risk genes. Finally, we are hoping that this review may open new area of research for AD treatment.
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16
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Cross-talk between the epigenome and neural circuits in drug addiction. PROGRESS IN BRAIN RESEARCH 2017; 235:19-63. [PMID: 29054289 DOI: 10.1016/bs.pbr.2017.08.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Drug addiction is a behavioral disorder characterized by dysregulated learning about drugs and associated cues that result in compulsive drug seeking and relapse. Learning about drug rewards and predictive cues is a complex process controlled by a computational network of neural connections interacting with transcriptional and molecular mechanisms within each cell to precisely guide behavior. The interplay between rapid, temporally specific neuronal activation, and longer-term changes in transcription is of critical importance in the expression of appropriate, or in the case of drug addiction, inappropriate behaviors. Thus, these factors and their interactions must be considered together, especially in the context of treatment. Understanding the complex interplay between epigenetic gene regulation and circuit connectivity will allow us to formulate novel therapies to normalize maladaptive reward behaviors, with a goal of modulating addictive behaviors, while leaving natural reward-associated behavior unaffected.
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17
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Sweatt JD, Tamminga CA. An epigenomics approach to individual differences and its translation to neuropsychiatric conditions. DIALOGUES IN CLINICAL NEUROSCIENCE 2017. [PMID: 27757063 PMCID: PMC5067146 DOI: 10.31887/dcns.2016.18.3/dsweatt] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
This review concerns epigenetic mechanisms and their roles in conferring interindividual differences, especially as related to experientially acquired and genetically driven changes in central nervous system (CNS) function. In addition, the review contains commentary regarding the possible ways in which epigenomic changes may contribute to neuropsychiatric conditions and disorders and ways in which epigenotyping might be cross-correlated with clinical phenotyping in the context of precision medicine. The review begins with a basic description of epigenetic marking in the CNS and how these changes are powerful regulators of gene readout. Means for characterizing the individual epigenotype are briefly described, with a focus on DNA cytosine methylation as a readily measurable, stable epigenetic mark. This background enables a discussion of how “epigenotyping” might be integrated along with genotyping and deep phenotyping as a means of implementing advanced precision medicine. Finally, the commentary addresses two exemplars when considering how epigenotype may correlate with and modulate cognitive and behavioral phenotype: schizophrenia and Rett syndrome. These two disorders provide an interesting compare-and-contrast example regarding possible epigenotypic regulation of behavior: whereas Rett syndrome is clearly established as being caused by disruption of the function of an epigenetic “reader” of the DNA cytosine methylome—methyl-CpG-binding protein 2 (MeCP2)—the case for a role for epigenetic mechanisms in schizophrenia is still quite speculative.
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Affiliation(s)
- J David Sweatt
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Carol A Tamminga
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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18
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Ranjan V, Singh S, Siddiqui SA, Tripathi S, Khan MY, Prakash A. Differential Histone Acetylation in Sub-Regions of Bed Nucleus of the Stria Terminalis Underlies Fear Consolidation and Extinction. Psychiatry Investig 2017; 14:350-359. [PMID: 28539954 PMCID: PMC5440438 DOI: 10.4306/pi.2017.14.3.350] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 05/31/2016] [Accepted: 07/06/2016] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE The hallmark of anxiety disorders is excessive fear. Previous studies have suggested that selective neural projections from Basal nucleus of stria terminalis (BNST) to amygdala and vice-versa precisely control the fear learning process. However the exact mechanism how the BNST controls fear consolidation and its extinction is largely unknown. In the present study we observed the changes in the BNST sub-regions following fear conditioning and its extinction. METHODS The change in the number of positive neurons was determined by immunohistochemistry for Acetyl H3 (Histone 3), Acetyl H4 (Histone 4), cAMP response element binding Protein (CBP) and c-fos in three sub-regions of the BNST namely the anterio-lateral BNST (STLP) and anterio-medial BNST (STMA), and lateral-ventral BNST (STLV) of rats subjected to auditory fear conditioning and extinction. RESULTS We found significant increase in the number of CBP, acetyl H3 and acetyl H4 positive neurons in the STMA and STLV but not in the STLP after fear conditioning. However, following fear extinction the number of CBP, acetyl H3 and acetyl H4 positive neurons increased significantly in the STLP but not in the STMA and STLV. Similar changes were observed in the number of c-fos positive neurons after fear consolidation and extinction. CONCLUSION The results from this study suggest that the differential histone acetylation in the different sub-regions of the BNST following fear learning and its extinction may be responsible for changes in the neuronal activation patterns resulting in either fear or less fear.
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Affiliation(s)
- Vandana Ranjan
- Department of Biochemistry, Dr. R M L Avadh University, Lucknow, India
| | - Sanjay Singh
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Lucknow, India
| | | | - Sukanya Tripathi
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Lucknow, India
| | - Mohd Yahiya Khan
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Lucknow, India
| | - Anand Prakash
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Lucknow, India
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19
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Faillace MP, Pisera-Fuster A, Medrano MP, Bejarano AC, Bernabeu RO. Short- and long-term effects of nicotine and the histone deacetylase inhibitor phenylbutyrate on novel object recognition in zebrafish. Psychopharmacology (Berl) 2017; 234:943-955. [PMID: 28130648 DOI: 10.1007/s00213-017-4532-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 01/09/2017] [Indexed: 12/16/2022]
Abstract
RATIONALE Zebrafish have a sophisticated color- and shape-sensitive visual system, so we examined color cue-based novel object recognition in zebrafish. We evaluated preference in the absence or presence of drugs that affect attention and memory retention in rodents: nicotine and the histone deacetylase inhibitor (HDACi) phenylbutyrate (PhB). OBJECTIVES The objective of this study was to evaluate whether nicotine and PhB affect innate preferences of zebrafish for familiar and novel objects after short- and long-retention intervals. METHODS We developed modified object recognition (OR) tasks using neutral novel and familiar objects in different colors. We also tested objects which differed with respect to the exploratory behavior they elicited from naïve zebrafish. RESULTS Zebrafish showed an innate preference for exploring red or green objects rather than yellow or blue objects. Zebrafish were better at discriminating color changes than changes in object shape or size. Nicotine significantly enhanced or changed short-term innate novel object preference whereas PhB had similar effects when preference was assessed 24 h after training. Analysis of other zebrafish behaviors corroborated these results. CONCLUSIONS Zebrafish were innately reluctant or prone to explore colored novel objects, so drug effects on innate preference for objects can be evaluated changing the color of objects with a simple geometry. Zebrafish exhibited recognition memory for novel objects with similar innate significance. Interestingly, nicotine and PhB significantly modified innate object preference.
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Affiliation(s)
- M P Faillace
- Department of Physiology and Institute of Physiology and Biophysics (IFIBIO), School of Medicine, University of Buenos Aires, Paraguay 2155 7th floor, C1121ABG, Ciudad Autónoma de Buenos Aires, Argentina
| | - A Pisera-Fuster
- Department of Physiology and Institute of Physiology and Biophysics (IFIBIO), School of Medicine, University of Buenos Aires, Paraguay 2155 7th floor, C1121ABG, Ciudad Autónoma de Buenos Aires, Argentina
| | - M P Medrano
- Department of Physiology and Institute of Physiology and Biophysics (IFIBIO), School of Medicine, University of Buenos Aires, Paraguay 2155 7th floor, C1121ABG, Ciudad Autónoma de Buenos Aires, Argentina
| | - A C Bejarano
- Department of Physiology and Institute of Physiology and Biophysics (IFIBIO), School of Medicine, University of Buenos Aires, Paraguay 2155 7th floor, C1121ABG, Ciudad Autónoma de Buenos Aires, Argentina
| | - R O Bernabeu
- Department of Physiology and Institute of Physiology and Biophysics (IFIBIO), School of Medicine, University of Buenos Aires, Paraguay 2155 7th floor, C1121ABG, Ciudad Autónoma de Buenos Aires, Argentina.
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20
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Ganai SA, Ramadoss M, Mahadevan V. Histone Deacetylase (HDAC) Inhibitors - emerging roles in neuronal memory, learning, synaptic plasticity and neural regeneration. Curr Neuropharmacol 2016; 14:55-71. [PMID: 26487502 PMCID: PMC4787286 DOI: 10.2174/1570159x13666151021111609] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 08/23/2015] [Accepted: 10/08/2015] [Indexed: 11/22/2022] Open
Abstract
Epigenetic regulation of neuronal signalling through histone acetylation dictates transcription programs that govern neuronal memory, plasticity and learning paradigms. Histone Acetyl Transferases (HATs) and Histone Deacetylases (HDACs) are antagonistic enzymes that regulate gene expression through acetylation and deacetylation of histone proteins around which DNA is wrapped inside a eukaryotic cell nucleus. The epigenetic control of HDACs and the cellular imbalance between HATs and HDACs dictate disease states and have been implicated in muscular dystrophy, loss of memory, neurodegeneration and autistic disorders. Altering gene expression profiles through inhibition of HDACs is now emerging as a powerful technique in therapy. This review presents evolving applications of HDAC inhibitors as potential drugs in neurological research and therapy. Mechanisms that govern their
expression profiles in neuronal signalling, plasticity and learning will be covered. Promising and exciting possibilities of HDAC inhibitors in memory formation, fear conditioning, ischemic stroke and neural regeneration have been detailed.
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Affiliation(s)
| | | | - Vijayalakshmi Mahadevan
- School of Chemical & Biotechnology SASTRA University Tirumalaisamudram, Thanjavur - 613 401 India.
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21
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Vierci G, Pannunzio B, Bornia N, Rossi FM. H3 and H4 Lysine Acetylation Correlates with Developmental and Experimentally Induced Adult Experience-Dependent Plasticity in the Mouse Visual Cortex. J Exp Neurosci 2016; 10:49-64. [PMID: 27891053 PMCID: PMC5117113 DOI: 10.4137/jen.s39888] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 08/21/2016] [Accepted: 08/27/2016] [Indexed: 12/30/2022] Open
Abstract
Histone posttranslational modifications play a fundamental role in orchestrating gene expression. In this work, we analyzed the acetylation of H3 and H4 histones (AcH3-AcH4) and its modulation by visual experience in the mouse visual cortex (VC) during normal development and in two experimental conditions that restore juvenile-like plasticity levels in adults (fluoxetine treatment and enriched environment). We found that AcH3-AcH4 declines with age and is upregulated by treatments restoring plasticity in the adult. We also found that visual experience modulates AcH3-AcH4 in young and adult plasticity-restored mice but not in untreated ones. Finally, we showed that the transporter vGAT is downregulated in adult plasticity-restored models. In summary, we identified a dynamic regulation of AcH3-AcH4, which is associated with high plasticity levels and enhanced by visual experience. These data, along with recent ones, indicate H3-H4 acetylation as a central hub in the control of experience-dependent plasticity in the VC.
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Affiliation(s)
- Gabriela Vierci
- Laboratorio de Neurociencias "Neuroplasticity Unit", Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Bruno Pannunzio
- Laboratorio de Neurociencias "Neuroplasticity Unit", Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Natalia Bornia
- Laboratorio de Neurociencias "Neuroplasticity Unit", Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Francesco M Rossi
- Laboratorio de Neurociencias "Neuroplasticity Unit", Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
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22
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Prenatal stressors in rodents: Effects on behavior. Neurobiol Stress 2016; 6:3-13. [PMID: 28229104 PMCID: PMC5314420 DOI: 10.1016/j.ynstr.2016.08.004] [Citation(s) in RCA: 163] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 08/07/2016] [Accepted: 08/08/2016] [Indexed: 12/13/2022] Open
Abstract
The current review focuses on studies in rodents published since 2008 and explores possible reasons for any differences they report in the effects of gestational stress on various types of behavior in the offspring. An abundance of experimental data shows that different maternal stressors in rodents can replicate some of the abnormalities in offspring behavior observed in humans. These include, anxiety, in juvenile and adult rats and mice, assessed in the elevated plus maze and open field tests and depression, detected in the forced swim and sucrose-preference tests. Deficits were reported in social interaction that is suggestive of pathology associated with schizophrenia, and in spatial learning and memory in adult rats in the Morris water maze test, but in most studies only males were tested. There were too few studies on the novel object recognition test at different inter-trial intervals to enable a conclusion about the effect of prenatal stress and whether any deficits are more prevalent in males. Among hippocampal glutamate receptors, NR2B was the only subtype consistently reduced in association with learning deficits. However, like in humans with schizophrenia and depression, prenatal stress lowered hippocampal levels of BDNF, which were closely correlated with decreases in hippocampal long-term potentiation. In mice, down-regulation of BDNF appeared to occur through the action of gene-methylating enzymes that are already increased above controls in prenatally-stressed neonates. In conclusion, the data obtained so far from experiments in rodents lend support to a physiological basis for the neurodevelopmental hypothesis of schizophrenia and depression.
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Identification and Characterization of the V(D)J Recombination Activating Gene 1 in Long-Term Memory of Context Fear Conditioning. Neural Plast 2015; 2016:1752176. [PMID: 26843989 PMCID: PMC4710954 DOI: 10.1155/2016/1752176] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 10/12/2015] [Indexed: 12/17/2022] Open
Abstract
An increasing body of evidence suggests that mechanisms related to the introduction and repair of DNA double strand breaks (DSBs) may be associated with long-term memory (LTM) processes. Previous studies from our group suggested that factors known to function in DNA recombination/repair machineries, such as DNA ligases, polymerases, and DNA endonucleases, play a role in LTM. Here we report data using C57BL/6 mice showing that the V(D)J recombination-activating gene 1 (RAG1), which encodes a factor that introduces DSBs in immunoglobulin and T-cell receptor genes, is induced in the amygdala, but not in the hippocampus, after context fear conditioning. Amygdalar induction of RAG1 mRNA, measured by real-time PCR, was not observed in context-only or shock-only controls, suggesting that the context fear conditioning response is related to associative learning processes. Furthermore, double immunofluorescence studies demonstrated the neuronal localization of RAG1 protein in amygdalar sections prepared after perfusion and fixation. In functional studies, intra-amygdalar injections of RAG1 gapmer antisense oligonucleotides, given 1 h prior to conditioning, resulted in amygdalar knockdown of RAG1 mRNA and a significant impairment in LTM, tested 24 h after training. Overall, these findings suggest that the V(D)J recombination-activating gene 1, RAG1, may play a role in LTM consolidation.
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Yuan RK, Hebert JC, Thomas AS, Wann EG, Muzzio IA. HDAC I inhibition in the dorsal and ventral hippocampus differentially modulates predator-odor fear learning and generalization. Front Neurosci 2015; 9:319. [PMID: 26441495 PMCID: PMC4585269 DOI: 10.3389/fnins.2015.00319] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 08/27/2015] [Indexed: 12/13/2022] Open
Abstract
Although predator odors are ethologically relevant stimuli for rodents, the molecular pathways and contribution of some brain regions involved in predator odor conditioning remain elusive. Inhibition of histone deacetylases (HDACs) in the dorsal hippocampus has been shown to enhance shock-induced contextual fear learning, but it is unknown if HDACs have differential effects along the dorso-ventral hippocampal axis during predator odor fear learning. We injected MS-275, a class I HDAC inhibitor, bilaterally in the dorsal or ventral hippocampus of mice and found that it had no effects on innate anxiety in either region. We then assessed the effects of MS-275 at different stages of fear learning along the longitudinal hippocampal axis. Animals were injected with MS-275 or vehicle after context pre-exposure (pre-conditioning injections), when a representation of the context is first formed, or after exposure to coyote urine (post-conditioning injections), when the context becomes associated with predator odor. When MS-275 was administered after context pre-exposure, dorsally injected animals showed enhanced fear in the training context but were able to discriminate it from a neutral environment. Conversely, ventrally injected animals did not display enhanced learning in the training context but generalized the fear response to a neutral context. However, when MS-275 was administered after conditioning, there were no differences between the MS-275 and vehicle control groups in either the dorsal or ventral hippocampus. Surprisingly, all groups displayed generalization to a neutral context, suggesting that predator odor exposure followed by a mild stressor such as restraint leads to fear generalization. These results may elucidate distinct functions of the dorsal and ventral hippocampus in predator odor-induced fear conditioning as well as some of the molecular mechanisms underlying fear generalization.
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Affiliation(s)
- Robin K Yuan
- Department of Psychology, University of Pennsylvania Philadelphia, PA, USA
| | - Jenna C Hebert
- Biological Basis of Behavior, University of Pennsylvania Philadelphia, PA, USA
| | - Arthur S Thomas
- Department of Biology, University of Pennsylvania Philadelphia, PA, USA
| | - Ellen G Wann
- Department of Psychology, University of Pennsylvania Philadelphia, PA, USA
| | - Isabel A Muzzio
- Department of Psychology, University of Pennsylvania Philadelphia, PA, USA ; Department of Biology, University of Texas at San Antonio San Antonio, TX, USA
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25
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Lopez-Atalaya JP, Valor LM, Barco A. Epigenetic factors in intellectual disability: the Rubinstein-Taybi syndrome as a paradigm of neurodevelopmental disorder with epigenetic origin. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 128:139-76. [PMID: 25410544 DOI: 10.1016/b978-0-12-800977-2.00006-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The number of genetic syndromes associated with intellectual disability that are caused by mutations in genes encoding chromatin-modifying enzymes has sharply risen in the last decade. We discuss here a neurodevelopmental disorder, the Rubinstein-Taybi syndrome (RSTS), originated by mutations in the genes encoding the lysine acetyltransferases CBP and p300. We first describe clinical and genetic aspects of the syndrome to later focus on the insight provided by the research in animal models of this disease. These studies have not only clarified the molecular etiology of RSTS and helped to dissect the developmental and adult components of the syndrome but also contributed to outline some important connections between epigenetics and cognition. We finally discuss how this body of research has opened new venues for the therapeutic intervention of this currently untreatable disease and present some of the outstanding questions in the field. We believe that the progress in the understanding of this rare disorder also has important implications for other intellectual disability disorders that share an epigenetic origin.
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Affiliation(s)
- Jose P Lopez-Atalaya
- Instituto de Neurociencias, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas, Alicante, Spain
| | - Luis M Valor
- Instituto de Neurociencias, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas, Alicante, Spain
| | - Angel Barco
- Instituto de Neurociencias, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas, Alicante, Spain
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26
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Vaissière T, Miller CA. DNA methylation: dynamic and stable regulation of memory. Biomol Concepts 2015; 2:459-67. [PMID: 25962048 DOI: 10.1515/bmc.2011.046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Accepted: 09/17/2011] [Indexed: 12/26/2022] Open
Abstract
Epigenetic mechanisms have emerged as a central process in learning and memory. Histone modifications and DNA methy-lation are epigenetic events that can mediate gene transcription. Interesting features of these epigenetic changes are their transient and long lasting potential. Recent advances in neuroscience suggest that DNA methylation is both dynamic and stable, mediating the formation and maintenance of memory. In this review, we will further illustrate the recent hypothesis that DNA methylation participates in the transcriptional regulation necessary for memory.
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27
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Padmanabhan J. Immunostaining analysis of tissue cultured cells and tissue sections using phospho-Histone H3 (Serine 10) antibody. Methods Mol Biol 2015; 1288:231-44. [PMID: 25827883 DOI: 10.1007/978-1-4939-2474-5_13] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Post-translational modifications of histones play an important role in regulation of gene expression through condensation and decondensation of chromatin structure. These modifications include acetylation, methylation, phosphorylation and ubiquitination. Phosphorylation on histones is associated with cellular responses such as DNA damage, transcription, chromatin compaction and mitosis or meiosis. One of the most extensively studied modifications of histones is the Serine 10 phosphorylation on histone H3 N-terminal tail. This specific phosphorylation on Histone H3 has been associated with condensation and transcriptional inactivation of mitotic chromosomes, but recent studies have suggested a role for this specific phosphorylation in chromatin relaxation and activation of transcription in interphase cells. Co-immunostaining analysis of cells using antibodies specific to serine 10P-Histone H3 together with those to cell cycle specific markers will allow us to determine the nature of phosphorylation in a cell cycle-specific manner. In a complex system, such as tissue specimens, analysis using P-Histone H3 and a cell type specific antibody will allow identification of specific cells that are affected by this histone modification. This is of particular interest in the field of cancer biology or neurobiology where identification or quantification of the transcriptionally active or mitotic cells will enable one to evaluate the progression of the disease development. The protocol described here provides details on how co-immunostaining and analysis can be performed in tissue cultured cells or tissue sections.
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Affiliation(s)
- Jaya Padmanabhan
- Department of Molecular Medicine, USF Health Byrd Alzheimer's Institute, University of South Florida, 4001 E Fletcher Ave, Tampa, 33613, FL, USA,
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28
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Grinkevich LN, Vorobiova OV. Role of modulatory mediator serotonin in induction of epigenetic processes during long-term memory formation in Helix. ACTA ACUST UNITED AC 2014. [DOI: 10.1134/s2079059714060094] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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29
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Prenatal stress induces spatial memory deficits and epigenetic changes in the hippocampus indicative of heterochromatin formation and reduced gene expression. Behav Brain Res 2014; 281:1-8. [PMID: 25496779 DOI: 10.1016/j.bbr.2014.12.001] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 10/29/2014] [Accepted: 12/01/2014] [Indexed: 02/08/2023]
Abstract
Stress during pregnancy has a wide variety of negative effects in both human [1] and animal offspring [2]. These effects are especially apparent in various forms of learning and memory such as object recognition [3] and spatial memory [4]. The cognitive effects of prenatal stress (PNS) may be mediated through epigenetic changes such as histone acetylation and DNA methylation [5]. As such, the present study investigated the effects of chronic unpredictable PNS on memory and epigenetic measures in adult offspring. Mice that underwent PNS exhibited impaired spatial memory in the Morris water maze, as well as sex-specific changes in levels of DNA methyltransferase (DNMT) 1 protein, and acetylated histone H3 (AcH3) in the hippocampus, and serum corticosterone. Male mice exposed to PNS exhibited decreased hippocampal AcH3, whereas female PNS mice displayed a further reduction in AcH3, as well as heightened hippocampal DNMT1 protein levels and corticosterone levels. These data suggest that PNS may epigenetically reduce transcription in the hippocampus, particularly in females in whom this effect may be related to increased baseline stress hormone levels, and which may underlie the sexual dimorphism in rates of mental illness in humans.
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Alberini CM, Kandel ER. The regulation of transcription in memory consolidation. Cold Spring Harb Perspect Biol 2014; 7:a021741. [PMID: 25475090 DOI: 10.1101/cshperspect.a021741] [Citation(s) in RCA: 224] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
De novo transcription of DNA is a fundamental requirement for the formation of long-term memory. It is required during both consolidation and reconsolidation, the posttraining and postreactivation phases that change the state of the memory from a fragile into a stable and long-lasting form. Transcription generates both mRNAs that are translated into proteins, which are necessary for the growth of new synaptic connections, as well as noncoding RNA transcripts that have regulatory or effector roles in gene expression. The result is a cascade of events that ultimately leads to structural changes in the neurons that mediate long-term memory storage. The de novo transcription, critical for synaptic plasticity and memory formation, is orchestrated by chromatin and epigenetic modifications. The complexity of transcription regulation, its temporal progression, and the effectors produced all contribute to the flexibility and persistence of long-term memory formation. In this article, we provide an overview of the mechanisms contributing to this transcriptional regulation underlying long-term memory formation.
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Affiliation(s)
| | - Eric R Kandel
- Zuckerman Mind Brain Behavior Institute, New York State Psychiatric Institute, New York, New York 10032 Department of Neuroscience, New York State Psychiatric Institute, New York, New York 10032 Kavli Institute for Brain Science, New York State Psychiatric Institute, New York, New York 10032 Howard Hughes Medical Institute, New York State Psychiatric Institute, New York, New York 10032 College of Physicians and Surgeons of Columbia University, New York State Psychiatric Institute, New York, New York 10032
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Federman N, Zalcman G, de la Fuente V, Fustiñana MS, Romano A. Epigenetic mechanisms and memory strength: a comparative study. ACTA ACUST UNITED AC 2014; 108:278-85. [PMID: 24978317 DOI: 10.1016/j.jphysparis.2014.06.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 05/12/2014] [Accepted: 06/16/2014] [Indexed: 01/04/2023]
Abstract
Memory consolidation requires de novo mRNA and protein synthesis. Transcriptional activation is controlled by transcription factors, their cofactors and repressors. Cofactors and repressors regulate gene expression by interacting with basal transcription machinery, remodeling chromatin structure and/or chemically modifying histones. Acetylation is the most studied epigenetic mechanism of histones modifications related to gene expression. This process is regulated by histone acetylases (HATs) and histone deacetylases (HDACs). More than 5 years ago, we began a line of research about the role of histone acetylation during memory consolidation. Here we review our work, presenting evidence about the critical role of this epigenetic mechanism during consolidation of context-signal memory in the crab Neohelice granulata, as well as during consolidation of novel object recognition memory in the mouse Mus musculus. Our evidence demonstrates that histone acetylation is a key mechanism in memory consolidation, functioning as a distinctive molecular feature of strong memories. Furthermore, we found that the strength of a memory can be characterized by its persistence or its resistance to extinction. Besides, we found that the role of this epigenetic mechanism regulating gene expression only in the formation of strongest memories is evolutionarily conserved.
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Affiliation(s)
- Noel Federman
- Laboratorio de Neurobiología de la Memoria, Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. IFIByNE, CONICET, Ciudad Universitaria, Pab. II, 2do piso, 1428EHA Buenos Aires, Argentina.
| | - Gisela Zalcman
- Laboratorio de Neurobiología de la Memoria, Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. IFIByNE, CONICET, Ciudad Universitaria, Pab. II, 2do piso, 1428EHA Buenos Aires, Argentina
| | - Verónica de la Fuente
- Laboratorio de Neurobiología de la Memoria, Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. IFIByNE, CONICET, Ciudad Universitaria, Pab. II, 2do piso, 1428EHA Buenos Aires, Argentina
| | - Maria Sol Fustiñana
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Arturo Romano
- Laboratorio de Neurobiología de la Memoria, Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. IFIByNE, CONICET, Ciudad Universitaria, Pab. II, 2do piso, 1428EHA Buenos Aires, Argentina
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Grinkevich LN. Studies of Histone H3 Methylation during the Formation of Long-Term Memory. ACTA ACUST UNITED AC 2014. [DOI: 10.1007/s11055-014-9953-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Abstract
Epigenetic regulation of cellular identity and function is at least partly achieved through changes in covalent modifications on DNA and histones. Much progress has been made in recent years to understand how these covalent modifications affect cell identity and function. Despite the advances, whether and how epigenetic factors contribute to memory formation is still poorly understood. In this review, we discuss recent progress in elucidating epigenetic mechanisms of learning and memory, primarily at the DNA level, and look ahead to discuss their potential implications in reward memory and development of drug addiction.
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Affiliation(s)
- Luis M Tuesta
- Howard Hughes Medical Institute, Boston, MA, USA Program in Cellular and Molecular Medicine Boston Children's Hospital, Boston, MA, USA Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Yi Zhang
- Howard Hughes Medical Institute, Boston, MA, USA Program in Cellular and Molecular Medicine Boston Children's Hospital, Boston, MA, USA Department of Genetics, Harvard Medical School, Boston, MA, USA Harvard Stem Cell Institute Harvard Medical School, Boston, MA, USA
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Rudenko A, Tsai LH. Epigenetic modifications in the nervous system and their impact upon cognitive impairments. Neuropharmacology 2014; 80:70-82. [PMID: 24495398 DOI: 10.1016/j.neuropharm.2014.01.043] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 01/23/2014] [Accepted: 01/24/2014] [Indexed: 12/13/2022]
Abstract
Epigenetic regulation has been long considered to be a critical mechanism in the control of key aspects of cellular functions such as cell division, growth, and cell fate determination. Exciting recent developments have demonstrated that epigenetic mechanisms can also play necessary roles in the nervous system by regulating, for example, neuronal gene expression, DNA damage, and genome stability. Despite the fact that postmitotic neurons are developmentally less active then dividing cells, epigenetic regulation appears to provide means of both long-lasting and very dynamic regulation of neuronal function. Growing evidence indicates that epigenetic mechanisms in the central nervous system (CNS) are important for regulating not only specific aspects of individual neuronal metabolism but also for maintaining function of neuronal circuits and regulating their behavioral outputs. Multiple reports demonstrated that higher-level cognitive behaviors, such as learning and memory, are subject to a sophisticated epigenetic control, which includes interplay between multiple mechanisms of neuronal chromatin modification. Experiments with animal models have demonstrated that various epigenetic manipulations can affect cognition in different ways, from severe dysfunction to substantial improvement. In humans, epigenetic dysregulation has been known to underlie a number of disorders that are accompanied by mental impairment. Here, we review some of the epigenetic mechanisms that regulate cognition and how their disruption may contribute to cognitive dysfunctions. Due to the fact that histone acetylation and DNA methylation are some of the best-studied and critically important epigenomic modifications our research team has particularly strong expertise in, in this review, we are going to concentrate on histone acetylation, as well as DNA methylation/hydroxymethylation, in the mammalian CNS. Additional epigenetic modifications, not surveyed here, are being discussed in depth in the other review articles in this issue of Neuropharmacology.
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Affiliation(s)
- Andrii Rudenko
- Picower Institute for Learning and Memory, Howard Hughes Medical Institute, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Li-Huei Tsai
- Picower Institute for Learning and Memory, Howard Hughes Medical Institute, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
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Pandian GN, Taylor RD, Junetha S, Saha A, Anandhakumar C, Vaijayanthi T, Sugiyama H. Alteration of epigenetic program to recover memory and alleviate neurodegeneration: prospects of multi-target molecules. Biomater Sci 2014; 2:1043-1056. [DOI: 10.1039/c4bm00068d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Next-generation sequence-specific small molecules modulating the epigenetic enzymes (DNMT/HDAC) and signalling factors can precisely turn ‘ON’ the multi-gene network in a neural cell.
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Affiliation(s)
- Ganesh N. Pandian
- Institute for Integrated Cell-Material Sciences (iCeMS)
- Kyoto University
- Kyoto 606-8502, Japan
| | - Rhys D. Taylor
- Department of Chemistry
- Graduate School of Science
- Kyoto University
- Kyoto 606-8501, Japan
| | - Syed Junetha
- Department of Chemistry
- Graduate School of Science
- Kyoto University
- Kyoto 606-8501, Japan
| | - Abhijit Saha
- Department of Chemistry
- Graduate School of Science
- Kyoto University
- Kyoto 606-8501, Japan
| | - Chandran Anandhakumar
- Department of Chemistry
- Graduate School of Science
- Kyoto University
- Kyoto 606-8501, Japan
| | - Thangavel Vaijayanthi
- Department of Chemistry
- Graduate School of Science
- Kyoto University
- Kyoto 606-8501, Japan
| | - Hiroshi Sugiyama
- Institute for Integrated Cell-Material Sciences (iCeMS)
- Kyoto University
- Kyoto 606-8502, Japan
- Department of Chemistry
- Graduate School of Science
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Abstract
Over the past 25 years, the broad field of epigenetics and, over the past decade in particular, the emerging field of neuroepigenetics have begun to have tremendous impact in the areas of learned behavior, neurotoxicology, CNS development, cognition, addiction, and psychopathology. However, epigenetics is such a new field that in most of these areas the impact is more in the category of fascinating implications as opposed to established facts. In this brief commentary, I will attempt to address and delineate some of the open questions and areas of opportunity that discoveries in epigenetics are providing to the discipline of neuroscience.
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Bekinschtein P, Cammarota M, Medina JH. BDNF and memory processing. Neuropharmacology 2013; 76 Pt C:677-83. [PMID: 23688925 DOI: 10.1016/j.neuropharm.2013.04.024] [Citation(s) in RCA: 246] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 03/14/2013] [Accepted: 04/08/2013] [Indexed: 01/19/2023]
Abstract
Brain-derived neurotrophic factor has emerged as one of the most important molecules involved in memory. Its wide role in different types of memories that depend on different structures as well as its involvement in distinct memory stages points at BDNF as one likely target to treat cognitive impairments and anxiety-related memory disorders. However, regulation of BDNF expression is very complex as well as its modes of action. Here we describe the latest research carried out on the function of BDNF in memory to illustrate such complexity. This article is part of the Special Issue entitled 'BDNF Regulation of Synaptic Structure, Function, and Plasticity'.
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Affiliation(s)
- Pedro Bekinschtein
- Instituto de Biologia Celular y Neurociencias, Facultad de Medicina, UBA, Argentina
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Pirooznia SK, Elefant F. Targeting specific HATs for neurodegenerative disease treatment: translating basic biology to therapeutic possibilities. Front Cell Neurosci 2013; 7:30. [PMID: 23543406 PMCID: PMC3610086 DOI: 10.3389/fncel.2013.00030] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Accepted: 03/10/2013] [Indexed: 12/28/2022] Open
Abstract
Dynamic epigenetic regulation of neurons is emerging as a fundamental mechanism by which neurons adapt their transcriptional responses to specific developmental and environmental cues. While defects within the neural epigenome have traditionally been studied in the context of early developmental and heritable cognitive disorders, recent studies point to aberrant histone acetylation status as a key mechanism underlying acquired inappropriate alterations of genome structure and function in post-mitotic neurons during the aging process. Indeed, it is becoming increasingly evident that chromatin acetylation status can be impaired during the lifetime of neurons through mechanisms related to loss of function of histone acetyltransferase (HAT) activity. Several HATs have been shown to participate in vital neuronal functions such as regulation of neuronal plasticity and memory formation. As such, dysregulation of such HATs has been implicated in the pathogenesis associated with age-associated neurodegenerative diseases and cognitive decline. In order to counteract the loss of HAT function in neurodegenerative diseases, the current therapeutic strategies involve the use of small molecules called histone deacetylase (HDAC) inhibitors that antagonize HDAC activity and thus enhance acetylation levels. Although this strategy has displayed promising therapeutic effects, currently used HDAC inhibitors lack target specificity, raising concerns about their applicability. With rapidly evolving literature on HATs and their respective functions in mediating neuronal survival and higher order brain function such as learning and memory, modulating the function of specific HATs holds new promises as a therapeutic tool in neurodegenerative diseases. In this review, we focus on the recent progress in research regarding epigenetic histone acetylation mechanisms underlying neuronal activity and cognitive function. We discuss the current understanding of specific HDACs and HATs in neurodegenerative diseases and the future promising prospects of using specific HAT based therapeutic approaches.
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Wang YJ, Okutani F, Murata Y, Taniguchi M, Namba T, Kaba H. Histone acetylation in the olfactory bulb of young rats facilitates aversive olfactory learning and synaptic plasticity. Neuroscience 2013; 232:21-31. [DOI: 10.1016/j.neuroscience.2012.12.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Revised: 12/04/2012] [Accepted: 12/05/2012] [Indexed: 01/10/2023]
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Rudenko A, Tsai LH. Epigenetic regulation in memory and cognitive disorders. Neuroscience 2013; 264:51-63. [PMID: 23291453 DOI: 10.1016/j.neuroscience.2012.12.034] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 12/18/2012] [Accepted: 12/19/2012] [Indexed: 01/29/2023]
Abstract
While the importance of epigenetic mechanisms is well established for numerous aspects of cell differentiation and development, recent findings have shown epigenetic processes to be a critical regulatory component in postmitotic neurons. Particularly intriguing, and potentially significant, are data demonstrating epigenetic regulation of cognitive behaviors. Different aspects of learning and memory appear to be regulated at the level of epigenetic chromatin modifications. Furthermore, it is becoming clear that the dysfunction of epigenetic mechanisms can lead to various disorders accompanied by significant mental impairment. Here, we review the evidence for the epigenetic control of cognition and the role of epigenetic dysregulation in mental disorders. A better understanding of epigenetic mechanisms will increase our fundamental knowledge of cognition and also provide new and exciting avenues of treatment for various mental disorders.
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Affiliation(s)
- A Rudenko
- Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Howard Hughes Medical Institute, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
| | - L-H Tsai
- Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Howard Hughes Medical Institute, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
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Abstract
One of the most exciting discoveries in the learning and memory field in the past two decades is the observation that active regulation of gene expression is necessary for experience to trigger lasting functional and behavioral change, in a wide variety of species, including humans. Thus, as opposed to the traditional view of 'nature' (genes) being separate from 'nurture' (environment and experience), it is now clear that experience actively drives alterations in central nervous system (CNS) gene expression in an ongoing fashion, and that the resulting transcriptional changes are necessary for experience to trigger altered long-term behavior. In parallel over the past decade, epigenetic mechanisms, including regulation of chromatin structure and DNA methylation, have been shown to be potent regulators of gene transcription in the CNS. In this review, we describe data supporting the hypothesis that epigenetic molecular mechanisms, especially DNA methylation and demethylation, drive long-term behavioral change through active regulation of gene transcription in the CNS. Specifically, we propose that epigenetic molecular mechanisms underlie the formation and stabilization of context- and cue-triggered fear conditioning based in the hippocampus and amygdala, a conclusion reached in a wide variety of studies using laboratory animals. Given the relevance of cued and contextual fear conditioning to post-traumatic stress, by extension we propose that these mechanisms may contribute to post-traumatic stress disorder (PTSD) in humans. Moreover, we speculate that epigenetically based pharmacotherapy may provide a new avenue of drug treatment for PTSD-related cognitive and behavioral function.
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Affiliation(s)
- Iva B Zovkic
- Department of Neurobiology, Evelyn F. McKnight Brain Institute, University of Alabama, Birmingham, AL, USA
| | - J David Sweatt
- Department of Neurobiology, Evelyn F. McKnight Brain Institute, University of Alabama, Birmingham, AL, USA,Department of Neurobiology, Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, 1010 Shelby Building, 1825 University Boulevard, Birmingham, AL 35294-2182, USA, Tel: +205 975 5196, Fax: +205 934 6571, E-mail:
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Abstract
Epigenetic remodeling and modifications of chromatin structure by DNA methylation and histone modifications represent central mechanisms for the regulation of neuronal gene expression during brain development, higher-order processing, and memory formation. Emerging evidence implicates epigenetic modifications not only in normal brain function, but also in neuropsychiatric disorders. This review focuses on recent findings that disruption of chromatin modifications have a major role in the neurodegeneration associated with ischemic stroke and epilepsy. Although these disorders differ in their underlying causes and pathophysiology, they share a common feature, in that each disorder activates the gene silencing transcription factor REST (repressor element 1 silencing transcription factor), which orchestrates epigenetic remodeling of a subset of 'transcriptionally responsive targets' implicated in neuronal death. Although ischemic insults activate REST in selectively vulnerable neurons in the hippocampal CA1, seizures activate REST in CA3 neurons destined to die. Profiling the array of genes that are epigenetically dysregulated in response to neuronal insults is likely to advance our understanding of the mechanisms underlying the pathophysiology of these disorders and may lead to the identification of novel therapeutic strategies for the amelioration of these serious human conditions.
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Konsoula Z, Barile FA. Epigenetic histone acetylation and deacetylation mechanisms in experimental models of neurodegenerative disorders. J Pharmacol Toxicol Methods 2012; 66:215-20. [PMID: 22902970 DOI: 10.1016/j.vascn.2012.08.001] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 08/03/2012] [Indexed: 10/28/2022]
Abstract
INTRODUCTION Epigenetic modifications, such as histone acetylation and deacetylation, are responsible for maintaining chromatin stability. As such, they have been implicated in a wide range of neurodegenerative disorders. METHODS Histone acetylation involves the presentation of an acetyl group to lysine residues at the N terminus of histone proteins. Conversely, histone deacetylation involves the detachment of acetyl groups. Transcriptionally active chromatin is linked to acetylated histones, and in mouse neurons, is implicated in proper learning and memory. DISCUSSION Proper functioning of histone deacetylases (HDACs) plays a pivotal role in histone acetylation homeostasis. RESULTS A wide range of brain disorders are associated with improper balances within histone acetylation mechanisms, resulting in transcriptional dysfunction and translational disparities. Treatment modalities with various HDAC inhibitors have emerged as potential new strategies for therapeutic intervention in neurodegenerative disease. HDAC inhibitors enhance synaptic plasticity, learning and memory in neurodegenerative disorders, such as Alzheimer's disease (AD), Huntington's disease (HD) and Parkinson's disease (PD). In this review, we discuss a variety of in vitro cellular models and in vivo mouse models of neurodegenerative diseases and the potential application of HDAC inhibitors to prevent and treat these disorders.
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Affiliation(s)
- Zacharoula Konsoula
- Department of Radiation Medicine, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, 3970 Reservoir Road, NW, Washington DC 20057, USA
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Danilova AB, Grinkevich LN. Failure of long-term memory formation in juvenile snails is determined by acetylation status of histone H3 and can be improved by NaB treatment. PLoS One 2012; 7:e41828. [PMID: 22848623 PMCID: PMC3405001 DOI: 10.1371/journal.pone.0041828] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Accepted: 06/29/2012] [Indexed: 01/15/2023] Open
Abstract
Background Animals’ capacities for different forms of learning do not mature simultaneously during ontogenesis but the molecular mechanisms behind the delayed development of specific types of memory are not fully understood. Mollusks are considered to be among the best models to study memory formation at the molecular level. Chromatin remodeling in developmental processes, as well as in long-term memory formation, was recently shown to play a major role. Histone acetylation is a key process in the chromatin remodeling and is regulated through the signaling cascades, for example MAPK/ERK. Previously, we found that MAPK/ERK is a key pathway in the formation of the food aversion reflex in Helix. Pretreatment with upstream ERK kinase inhibitor PD98059 prevented food avoidance learning in adult Helix. In contrast to adult snails, juveniles possess immature plasticity mechanisms of the avoidance reflex until the age of 2–3 months while the MAPK/ERK cascade is not activated after aversive learning. In the present study, we focused on the potential MAPK/ERK target - histone H3. Methodology/Principal Findings Here we found that a significant increase in histone H3 acetylation occurs in adult animals after learning, whereas no corresponding increase was observed in juveniles. The acetylation of histone H3 is regulated by ERK kinase, since the upstream ERK kinase inhibitor PD98059 prevented the increase of histone H3 acetylation upon learning. We found that the injection of histone deacetylase inhibitor sodium butyrate (NaB) prior to training led to induction in histone H3 acetylation and significantly ameliorated long-term memory formation in juvenile snails. Conclusions/Significance Thus, MAPK/ERK-dependent histone H3 acetylation plays an essential role in the formation of food aversion in Helix. Dysfunction of the MAPK/ERK dependent histone H3 acetylation might determine the deficiency of avoidance behavior and long-term plasticity in juvenile animals. Stimulation of histone H3 acetylation in juvenile animals by NaB promoted avoidance plasticity.
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Affiliation(s)
- Alexandra B. Danilova
- Laboratory of regulation of functions of brain neurons, Pavlov Institute of Physiology Russian Academy of Sciences, St. Petersburg, Russia
| | - Larisa N. Grinkevich
- Laboratory of regulation of functions of brain neurons, Pavlov Institute of Physiology Russian Academy of Sciences, St. Petersburg, Russia
- * E-mail:
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Huerta-Rivas A, López-Rubalcava C, Sánchez-Serrano SL, Valdez-Tapia M, Lamas M, Cruz SL. Toluene impairs learning and memory, has antinociceptive effects, and modifies histone acetylation in the dentate gyrus of adolescent and adult rats. Pharmacol Biochem Behav 2012; 102:48-57. [DOI: 10.1016/j.pbb.2012.03.018] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 03/14/2012] [Accepted: 03/24/2012] [Indexed: 12/18/2022]
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Federman N, Fustiñana MS, Romano A. Reconsolidation involves histone acetylation depending on the strength of the memory. Neuroscience 2012; 219:145-56. [PMID: 22659565 DOI: 10.1016/j.neuroscience.2012.05.057] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 05/22/2012] [Accepted: 05/23/2012] [Indexed: 12/18/2022]
Abstract
Gene expression is a necessary step for memory re-stabilization after retrieval, a process known as reconsolidation. Histone acetylation is a fundamental mechanism involved in epigenetic regulation of gene expression and has been implicated in memory consolidation. However, few studies are available in reconsolidation, all of them in vertebrate models. Additionally, the recruitment of histone acetylation as a function of different memory strengths has not been systematically analyzed before. Here we studied the role of histone acetylation in reconsolidation using a well-characterized memory model in invertebrate, the context-signal memory in the crab Chasmagnathus. Firstly, we found an increase in histone H3 acetylation 1h after memory reactivation returning to basal levels at 3 h. Strikingly, this increment was only detected during reconsolidation of a long-term memory induced by a strong training of 30 trials, but not for a short-term memory formed by a weak training of five trials or for a long-term memory induced by a standard training of 15 trials. Furthermore, we showed that a weak memory which was enhanced during consolidation by histone deacetylases inhibition, also recruited histone H3 acetylation in reconsolidation as the strong training does. Accordingly, we found the first evidence that the administration of a histone acetyl transferase inhibitor during memory reconsolidation impairs long-term memory re-stabilization. Finally, we found that strong training memory, at variance with the standard training memory, was resistant to extinction, indicating that such strong training induced in fact a stronger memory. In conclusion, the results presented here support that the participation of histone acetylation during reconsolidation is an evolutionary conserved feature and constitutes a specific molecular characteristic of strong memories.
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Affiliation(s)
- N Federman
- Laboratorio de Neurobiología de la Memoria, Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, IFIByNE, CONICET, Ciudad Universitaria, Pab. II, 2do piso (1428EHA), Buenos Aires, Argentina
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Puckett RE, Lubin FD. Epigenetic mechanisms in experience-driven memory formation and behavior. Epigenomics 2012; 3:649-64. [PMID: 22126252 DOI: 10.2217/epi.11.86] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Epigenetic mechanisms have long been associated with the regulation of gene-expression changes accompanying normal neuronal development and cellular differentiation; however, until recently these mechanisms were believed to be statically quiet in the adult brain. Behavioral neuroscientists have now begun to investigate these epigenetic mechanisms as potential regulators of gene-transcription changes in the CNS subserving synaptic plasticity and long-term memory (LTM) formation. Experimental evidence from learning and memory animal models has demonstrated that active chromatin remodeling occurs in terminally differentiated postmitotic neurons, suggesting that these molecular processes are indeed intimately involved in several stages of LTM formation, including consolidation, reconsolidation and extinction. Such chromatin modifications include the phosphorylation, acetylation and methylation of histone proteins and the methylation of associated DNA to subsequently affect transcriptional gene readout triggered by learning. The present article examines how such learning-induced epigenetic changes contribute to LTM formation and influence behavior. In particular, this article is a survey of the specific epigenetic mechanisms that have been demonstrated to regulate gene expression for both transcription factors and growth factors in the CNS, which are critical for LTM formation and storage, as well as how aberrant epigenetic processing can contribute to psychological states such as schizophrenia and drug addiction. Together, the findings highlighted in this article support a novel role for epigenetic mechanisms in the adult CNS serving as potential key molecular regulators of gene-transcription changes necessary for LTM formation and adult behavior.
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Affiliation(s)
- Rosemary E Puckett
- Evelyn F McKnight Brain Institute, Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Neelamegam R, Ricq EL, Malvaez M, Patnaik D, Norton S, Carlin SM, Hill IT, Wood MA, Haggarty SJ, Hooker JM. Brain-penetrant LSD1 inhibitors can block memory consolidation. ACS Chem Neurosci 2012; 3:120-128. [PMID: 22754608 DOI: 10.1021/cn200104y] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Modulation of histone modifications in the brain may represent a new mechanism for brain disorder therapy. Post-translational modifications of histones regulate gene expression, affecting major cellular processes such as proliferation, differentiation, and function. An important enzyme involved in one of these histone modifications is lysine specific demethylase 1 (LSD1). This enzyme is flavin-dependent and exhibits homology to amine oxidases. Parnate (2-phenylcyclopropylamine (2-PCPA); tranylcypromine) is a potent inhibitor of monoamine oxidases and derivatives of 2-PCPA have been used for development of selective LSD1 inhibitors based on the ability to form covalent adducts with flavin adenine dinucleotide (FAD). Here we report the synthesis and in vitro characterization of LSD1 inhibitors that bond covalently to FAD. The two most potent and selective inhibitors were used to demonstrate brain penetration when administered systemically to rodents. First, radiosynthesis of a positron-emitting analog was used to obtain preliminary bio-distribution data and whole brain time-activity curves. Second, we demonstrate that this series of LSD1 inhibitors is capable of producing a cognitive effect in a mouse model. By using a memory formation paradigm, novel object recognition, we show that LSD1 inhibition can abolish long-term memory formation without affecting short-term memory, providing further evidence for the importance of reversible histone methylation in the function of the nervous system.
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Affiliation(s)
- Ramesh Neelamegam
- Department
of Radiology, Athinoula
A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
02129, United States
| | - Emily L. Ricq
- Department
of Radiology, Athinoula
A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
02129, United States
- Department
of Chemistry and
Chemical Biology, Harvard University, 12
Oxford Street, Cambridge, Massachusetts 02138, United States
- Department of Neurology, Center
for Human Genetic Research, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114,
United States
| | - Melissa Malvaez
- Department of Neurobiology and
Behavior, Center for the Neurobiology of Learning and Memory, University of California, Irvine, California 92697-3800,
United States
| | - Debasis Patnaik
- Department of Neurology, Center
for Human Genetic Research, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114,
United States
| | - Stephanie Norton
- Department of Neurology, Center
for Human Genetic Research, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114,
United States
| | - Stephen M. Carlin
- Department
of Radiology, Athinoula
A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
02129, United States
| | - Ian T. Hill
- Department
of Radiology, Athinoula
A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
02129, United States
| | - Marcelo A. Wood
- Department of Neurobiology and
Behavior, Center for the Neurobiology of Learning and Memory, University of California, Irvine, California 92697-3800,
United States
| | - Stephen J. Haggarty
- Department of Neurology, Center
for Human Genetic Research, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114,
United States
- Stanley Center for Psychiatric Research at the Broad Institute of Harvard and MIT, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Jacob M. Hooker
- Department
of Radiology, Athinoula
A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
02129, United States
- Brookhaven National Laboratory, Upton, New York 11973-5000, United
States
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Molfese DL. Advancing neuroscience through epigenetics: molecular mechanisms of learning and memory. Dev Neuropsychol 2012; 36:810-27. [PMID: 21978007 DOI: 10.1080/87565641.2011.606395] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Humans share 96% of our 30,000 genes with Chimpanzees. The 1,200 genes that differ appear at first glance insufficient to describe what makes us human and them apes. However, we are now discovering that the mechanisms that regulate how genes are expressed tell a much richer story than our DNA alone. Sections of our DNA are constantly being turned on or off, marked for easy access, or secluded and hidden away, all in response to ongoing cellular activity. In the brain, neurons encode information-in effect memories-at the cellular level. Yet while memories may last a lifetime, neurons are dynamic structures. Every protein in the synapse undergoes some form of turnover, some with half-lives of only hours. How can a memory persist beyond the lifetimes of its constitutive molecular building blocks? Epigenetics-changes in gene expression that do not alter the underlying DNA sequence-may be the answer. In this article, epigenetic mechanisms including DNA methylation and acetylation or methylation of the histone proteins that package DNA are described in the context of animal learning. Through the interaction of these modifications a "histone code" is emerging wherein individual memories leave unique memory traces at the molecular level with distinct time courses. A better understanding of these mechanisms has implications for treatment of memory disorders caused by normal aging or diseases including schizophrenia, Alzheimer's, depression, and drug addiction.
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Affiliation(s)
- David L Molfese
- Department of Psychology, University of Houston, Houston, Texas 77204-5022, USA.
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