1
|
Liu SX, Harris AC, Gewirtz JC. How life events may confer vulnerability to addiction: the role of epigenetics. Front Mol Neurosci 2024; 17:1462769. [PMID: 39359689 PMCID: PMC11446245 DOI: 10.3389/fnmol.2024.1462769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2024] [Accepted: 09/02/2024] [Indexed: 10/04/2024] Open
Abstract
Substance use disorder (SUD) represents a large and growing global health problem. Despite the strong addictive potency of drugs of abuse, only a minority of those exposed develop SUDs. While certain life experiences (e.g., childhood trauma) may increase subsequent vulnerability to SUDs, mechanisms underlying these effects are not yet well understood. Given the chronic and relapsing nature of SUDs, and the length of time that can elapse between prior life events and subsequent drug exposure, changes in SUD vulnerability almost certainly involve long-term epigenetic dysregulation. To validate this idea, functional effects of specific epigenetic modifications in brain regions mediating reinforcement learning (e.g., nucleus accumbens, prefrontal cortex) have been investigated in a variety of animal models of SUDs. In addition, the effects of epigenetic modifications produced by prior life experiences on subsequent SUD vulnerability have been studied, but mostly in a correlational manner. Here, we review how epigenetic mechanisms impact SUD-related behavior in animal models and summarize our understanding of the relationships among life experiences, epigenetic regulation, and future vulnerability to SUDs. Despite variations in study design, epigenetic modifications that most consistently affect SUD-related behavior are those that produce predominantly unidirectional effects on gene regulation, such as DNA methylation and histone phosphorylation. Evidence explicitly linking environmentally induced epigenetic modifications to subsequent SUD-related behavior is surprisingly sparse. We conclude by offering several directions for future research to begin to address this critical research gap.
Collapse
Affiliation(s)
- Shirelle X Liu
- Department of Psychology, University of Minnesota, Minneapolis, MN, United States
| | - Andrew C Harris
- Department of Psychology, University of Minnesota, Minneapolis, MN, United States
- Department of Medicine, University of Minnesota, Minneapolis, MN, United States
- Hennepin Healthcare Research Institute, Minneapolis, MN, United States
| | - Jonathan C Gewirtz
- Department of Psychology, University of Minnesota, Minneapolis, MN, United States
- Department of Psychology, Arizona State University, Tempe, AZ, United States
| |
Collapse
|
2
|
Borges JV, Pires VN, de Freitas BS, Rübensam G, Vieira VC, de Souza Dos Santos C, Schröder N, Bromberg E. Behavior, BDNF and epigenetic mechanisms in response to social isolation and social support in middle aged rats exposed to chronic stress. Behav Brain Res 2023; 441:114303. [PMID: 36657665 DOI: 10.1016/j.bbr.2023.114303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Revised: 01/11/2023] [Accepted: 01/15/2023] [Indexed: 01/18/2023]
Abstract
Social deprivation can be stressful for group-living mammals. On the other hand, an amazing response of these animals to stress is seeking social contact to give and receive joint protection in threatening situations. We explored the effects of social isolation and social support on epigenetic and behavioral responses to chronic stress. More specifically, we investigated the behavioral responses, corticosterone levels, BDNF gene expression, and markers of hippocampal epigenetic alterations (levels of H3K9 acetylation and methylation, H3K27 methylation, HDAC5, DNMT1, and DNMT3a gene expressions) in middle-aged adult rats maintained in different housing conditions (isolation or accompanied housing) and exposed to the chronic unpredictable stress protocol (CUS). Isolation was associated with decreased basal levels of corticosterone, impaired long-term memory, and decreased expression of the BDNF gene, besides altering the balance of H3K9 from acetylation to methylation and increasing the DNMT1 gene expression. The CUS protocol decreased H3K9 acetylation, besides increasing H3K27 methylation and DNMT1 gene expression, but had no significant effects on memory and BDNF gene expression. Interestingly, the effects of CUS on corticosterone and HDAC5 gene expression were seen only in isolated animals, whereas the effects of CUS on DNMT1 gene expression were more pronounced in isolated than accompanied animals. In conclusion, social isolation in middle age showed broader effects than chronic unpredictable stress on behavioral and epigenetic alterations potentially associated with decreased BDNF expression. Moreover, social support prevented the adverse effects of CUS on HPA axis functioning, HDAC5, and DNMT1 gene expressions.
Collapse
Affiliation(s)
- Juliano Viana Borges
- Laboratory of Biology and Development of the Nervous System, School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul, Ipiranga Av. 6681, 90619-900 Porto Alegre, Brazil
| | - Vivian Naziaseno Pires
- Laboratory of Biology and Development of the Nervous System, School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul, Ipiranga Av. 6681, 90619-900 Porto Alegre, Brazil; Institute of Geriatrics and Gerontology, Pontifical Catholic University of Rio Grande do Sul, Ipiranga Av. 6690, 90610-000 Porto Alegre, Brazil
| | - Betânia Souza de Freitas
- Laboratory of Biology and Development of the Nervous System, School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul, Ipiranga Av. 6681, 90619-900 Porto Alegre, Brazil
| | - Gabriel Rübensam
- Center of Toxicology and Pharmacology Research, School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul, Brazil
| | - Vitória Corrêa Vieira
- Laboratory of Biology and Development of the Nervous System, School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul, Ipiranga Av. 6681, 90619-900 Porto Alegre, Brazil
| | - Cristophod de Souza Dos Santos
- Laboratory of Biology and Development of the Nervous System, School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul, Ipiranga Av. 6681, 90619-900 Porto Alegre, Brazil
| | - Nadja Schröder
- National Institute of Science and Technology for Translational Medicine (INCT-TM), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Brasília, Brazil; Department of Physiology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Elke Bromberg
- Laboratory of Biology and Development of the Nervous System, School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul, Ipiranga Av. 6681, 90619-900 Porto Alegre, Brazil; Institute of Geriatrics and Gerontology, Pontifical Catholic University of Rio Grande do Sul, Ipiranga Av. 6690, 90610-000 Porto Alegre, Brazil; National Institute of Science and Technology for Translational Medicine (INCT-TM), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Brasília, Brazil.
| |
Collapse
|
3
|
Modulation of the endoplasmic reticulum stress and unfolded protein response mitigates the behavioral effects of early-life stress. Pharmacol Rep 2023; 75:293-319. [PMID: 36843201 PMCID: PMC10060333 DOI: 10.1007/s43440-023-00456-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/25/2023] [Accepted: 01/29/2023] [Indexed: 02/28/2023]
Abstract
BACKGROUND Early-life stress (ELS) affects brain development and increases the risk of mental disorders associated with the dysfunction of the medial prefrontal cortex (mPFC). The mechanisms of ELS action are not well understood. Endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) are cellular processes involved in brain maturation through the regulation of pro-survival or proapoptotic processes. We hypothesized that ER stress and the UPR in the mPFC are involved in the neurobiology of ELS. METHODS We performed a maternal separation (MS) procedure from postnatal days 1 to 14 in rats. Before each MS, pups were injected with an inhibitor of ER stress, salubrinal or a vehicle. The mRNA and protein expression of UPR and apoptotic markers were evaluated in the mPFC using RT-qPCR and Western blot methods, respectively. We also estimated the numbers of neurons and glial cells using stereological methods. Additionally, we assessed behavioral phenotypes related to fear, anhedonia and response to psychostimulants. RESULTS MS slightly enhanced the activation of the UPR in juveniles and modulated the expression of apoptotic markers in juveniles and preadolescents but not in adults. Additionally, MS did not affect the numbers of neurons and glial cells at any age. Both salubrinal and vehicle blunted the expression of UPR markers in juvenile and preadolescent MS rats, often in a treatment-specific manner. Moreover, salubrinal and vehicle generally alleviated the behavioral effects of MS in preadolescent and adult rats. CONCLUSIONS Modulation of ER stress and UPR processes may potentially underlie susceptibility or resilience to ELS.
Collapse
|
4
|
Bekdash RA. Methyl Donors, Epigenetic Alterations, and Brain Health: Understanding the Connection. Int J Mol Sci 2023; 24:ijms24032346. [PMID: 36768667 PMCID: PMC9917111 DOI: 10.3390/ijms24032346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/18/2023] [Accepted: 01/21/2023] [Indexed: 01/27/2023] Open
Abstract
Methyl donors such as choline, betaine, folic acid, methionine, and vitamins B6 and B12 are critical players in the one-carbon metabolism and have neuroprotective functions. The one-carbon metabolism comprises a series of interconnected chemical pathways that are important for normal cellular functions. Among these pathways are those of the methionine and folate cycles, which contribute to the formation of S-adenosylmethionine (SAM). SAM is the universal methyl donor of methylation reactions such as histone and DNA methylation, two epigenetic mechanisms that regulate gene expression and play roles in human health and disease. Epigenetic mechanisms have been considered a bridge between the effects of environmental factors, such as nutrition, and phenotype. Studies in human and animal models have indicated the importance of the optimal levels of methyl donors on brain health and behavior across the lifespan. Imbalances in the levels of these micronutrients during critical periods of brain development have been linked to epigenetic alterations in the expression of genes that regulate normal brain function. We present studies that support the link between imbalances in the levels of methyl donors, epigenetic alterations, and stress-related disorders. Appropriate levels of these micronutrients should then be monitored at all stages of development for a healthier brain.
Collapse
Affiliation(s)
- Rola A Bekdash
- Department of Biological Sciences, Rutgers University, Newark, NJ 07102, USA
| |
Collapse
|
5
|
Venney CJ, Cayuela H, Rougeux C, Laporte M, Mérot C, Normandeau E, Leitwein M, Dorant Y, Præbel K, Kenchington E, Clément M, Sirois P, Bernatchez L. Genome-wide DNA methylation predicts environmentally driven life history variation in a marine fish. Evolution 2023; 77:186-198. [PMID: 36622671 DOI: 10.1093/evolut/qpac028] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 09/21/2022] [Accepted: 11/16/2022] [Indexed: 01/10/2023]
Abstract
Epigenetic modifications are thought to be one of the molecular mechanisms involved in plastic adaptive responses to environmental variation. However, studies reporting associations between genome-wide epigenetic changes and habitat-specific variations in life history traits (e.g., lifespan, reproduction) are still scarce, likely due to the recent application of methylome resequencing methods to non-model species. In this study, we examined associations between whole genome DNA methylation and environmentally driven life history variation in 2 lineages of a marine fish, the capelin (Mallotus villosus), from North America and Europe. In both lineages, capelin harbor 2 contrasting life history tactics (demersal vs. beach-spawning). Performing whole genome and methylome sequencing, we showed that life history tactics are associated with epigenetic changes in both lineages, though the effect was stronger in European capelin. Genetic differentiation between the capelin harboring different life history tactics was negligible, but we found genome-wide methylation changes in both lineages. We identified 9,125 European and 199 North American differentially methylated regions (DMRs) due to life history. Gene ontology (GO) enrichment analysis for both lineages revealed an excess of terms related to neural function. Our results suggest that environmental variation causes important epigenetic changes that are associated with contrasting life history tactics in lineages with divergent genetic backgrounds, with variable importance of genetic variation in driving epigenetic variation. Our study emphasizes the potential role of genome-wide epigenetic variation in adaptation to environmental variation.
Collapse
Affiliation(s)
- Clare J Venney
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Quebec City, QC, Canada
| | - Hugo Cayuela
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Quebec City, QC, Canada.,Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland.,University of Lyon, Université Claude Bernard Lyon 1, CNRS, UMR 5558, Laboratoire de Biométrie et Biologie Evolutive, Villeurbanne, France
| | - Clément Rougeux
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Martin Laporte
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Quebec City, QC, Canada
| | - Claire Mérot
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Quebec City, QC, Canada
| | - Eric Normandeau
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Quebec City, QC, Canada
| | - Maëva Leitwein
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Quebec City, QC, Canada
| | - Yann Dorant
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Quebec City, QC, Canada
| | - Kim Præbel
- Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Tromsø, Norway
| | - Ellen Kenchington
- Department of Fisheries and Oceans, Bedford Institute of Oceanography, Dartmouth, NS, Canada
| | - Marie Clément
- Centre for Fisheries Ecosystems Research, Fisheries and Marine Institute of Memorial University of Newfoundland, St. John's, NL, Canada.,Labrador Institute, Memorial University of Newfoundland, Happy Valley-Goose Bay, NL, Canada
| | - Pascal Sirois
- Département des sciences fondamentales, Université du Québec à Chicoutimi, Chicoutimi, QC, Canada
| | - Louis Bernatchez
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Quebec City, QC, Canada
| |
Collapse
|
6
|
Cheng Z, Su J, Zhang K, Jiang H, Li B. Epigenetic Mechanism of Early Life Stress-Induced Depression: Focus on the Neurotransmitter Systems. Front Cell Dev Biol 2022; 10:929732. [PMID: 35865627 PMCID: PMC9294154 DOI: 10.3389/fcell.2022.929732] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 05/31/2022] [Indexed: 11/13/2022] Open
Abstract
Depression has an alarmingly high prevalence worldwide. A growing body of evidence indicates that environmental factors significantly affect the neural development and function of the central nervous system and then induce psychiatric disorders. Early life stress (ELS) affects brain development and has been identified as a major cause of depression. It could promote susceptibility to stress in adulthood. Recent studies have found that ELS induces epigenetic changes that subsequently affect transcriptional rates of differentially expressed genes. The epigenetic modifications involved in ELS include histone modifications, DNA methylation, and non-coding RNA. Understanding of these genetic modifications may identify mechanisms that may lead to new interventions for the treatment of depression. Many reports indicate that different types of ELS induce epigenetic modifications of genes involved in the neurotransmitter systems, such as the dopaminergic system, the serotonergic system, the gamma-aminobutyric acid (GABA)-ergic system, and the glutamatergic system, which further regulate gene expression and ultimately induce depression-like behaviors. In this article, we review the effects of epigenetic modifications on the neurotransmitter systems in depression-like outcomes produced by different types of ELS in recent years, aiming to provide new therapeutic targets for patients who suffer from depression.
Collapse
Affiliation(s)
- Ziqian Cheng
- Jilin Provincial Key Laboratory on Molecular and Chemical Genetic, Second Hospital of Jilin University, Changchun, China
- Engineering Lab on Screening of Antidepressant Drugs, Jilin Province Development and Reform Commission, Changchun, China
| | - Jingyun Su
- Jilin Provincial Key Laboratory on Molecular and Chemical Genetic, Second Hospital of Jilin University, Changchun, China
- Engineering Lab on Screening of Antidepressant Drugs, Jilin Province Development and Reform Commission, Changchun, China
| | - Kai Zhang
- Central Laboratory, The Second Hospital of Jilin University, Jilin University, Changchun, China
| | - Huiyi Jiang
- Department of Pediatrics, The First Hospital of Jilin University, Changchun, China
- *Correspondence: Huiyi Jiang, ; Bingjin Li,
| | - Bingjin Li
- Jilin Provincial Key Laboratory on Molecular and Chemical Genetic, Second Hospital of Jilin University, Changchun, China
- Engineering Lab on Screening of Antidepressant Drugs, Jilin Province Development and Reform Commission, Changchun, China
- *Correspondence: Huiyi Jiang, ; Bingjin Li,
| |
Collapse
|
7
|
Niinep K, Anier K, Eteläinen T, Piepponen P, Kalda A. Repeated Ethanol Exposure Alters DNA Methylation Status and Dynorphin/Kappa-Opioid Receptor Expression in Nucleus Accumbens of Alcohol-Preferring AA Rats. Front Genet 2021; 12:750142. [PMID: 34899839 PMCID: PMC8652212 DOI: 10.3389/fgene.2021.750142] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 11/04/2021] [Indexed: 11/13/2022] Open
Abstract
Growing evidence suggests that epigenetic mechanisms, such as DNA methylation and demethylation, and histone modifications, are involved in the development of alcohol and drug addiction. However, studies of alcohol use disorder (AUD) that are focused on epigenetic DNA modifications and gene expression changes remain conflicting. Our aim was to study the effect of repeated ethanol consumption on epigenetic regulatory enzymes such as DNA methyltransferase and demethylase enzymes and whether those changes affected dynorphin/kappa-opioid receptor system in the Nucleus Accumbens (NAc). Two groups of male alcohol-preferring Alko Alcohol (AA) rats, rats which are selectively bred for high voluntary alcohol consumption and one group of male Wistar rats were used. The first group of AA rats had access to alcohol (10% ethanol solution) for 90 min on Mondays, Wednesdays and Fridays over a period of 3 weeks to establish a stable baseline of ethanol intake (AA-ethanol). The second group of AA rats (AA-water) and the Wistar rats (Wistar-water) were provided with water. Using qPCR, we found that voluntary alcohol drinking increased Dnmt1, -3a, and -3b mRNA levels and did not affect Tet family transcripts in the AA-ethanol group when compared with AA- and Wistar-water rats. DNMT and TET enzymatic activity measurements showed similar results to qPCR, where DNMT activity was increased in AA-ethanol group compared with AA-water and Wistar-water groups, with no statistically significant difference between groups in TET enzyme activity. In line with previous data, we found an increased percentage of global DNA methylation and hydroxymethylation in the AA-ethanol group compared with control rats. Finally, we investigated changes of selected candidate genes from dynorphin/kappa-opioid receptor system (Pdyn, Kor) and Dnmt3a genes that might be important in AUD-related behaviour. Our gene expression and promoter methylation analysis revealed a significant increase in the mRNA levels of Pdyn, Kor, and Dnmt3a in the AA-ethanol group, however, these changes can only be partially associate with the aberrant DNA methylation in promoter areas of the selected candidate genes. Thus, our findings suggest that the aberrant DNA methylation is rather one of the several mechanisms involved in gene expression regulation in AA rat model.
Collapse
Affiliation(s)
- Kerly Niinep
- Department of Pharmacology, University of Tartu, Tartu, Estonia
| | - Kaili Anier
- Department of Pharmacology, University of Tartu, Tartu, Estonia
| | - Tony Eteläinen
- Department of Pharmacology and Pharmacotherapy, University of Helsinki, Helsinki, Finland
| | - Petteri Piepponen
- Department of Pharmacology and Pharmacotherapy, University of Helsinki, Helsinki, Finland
| | - Anti Kalda
- Department of Pharmacology, University of Tartu, Tartu, Estonia
| |
Collapse
|
8
|
Cahill B, Poelker-Wells S, Prather JF, Li Y. A Glimpse Into the Sexual Dimorphisms in Major Depressive Disorder Through Epigenetic Studies. Front Neural Circuits 2021; 15:768571. [PMID: 34744641 PMCID: PMC8564393 DOI: 10.3389/fncir.2021.768571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 09/28/2021] [Indexed: 11/13/2022] Open
Abstract
Depression is an umbrella term used to describe a mood disorder with a broad spectrum of symptoms including a persistent feeling of sadness, loss of interest, and deficits in social behavior. Epigenetic research bridges the environmental and genetic landscape and has the potential to exponentially improve our understanding of such a complex disorder. Depression is also a sexually dimorphic disorder and variations exist within epigenetic modification sites between sexes. These sex-specific mediators may impact behavioral symptomology and could serve as therapeutic targets for treatments to improve behavioral deficits. This mini review will focus on the social behavior perspective of depression and specifically explore the sexually different epigenetic modifications on depression.
Collapse
Affiliation(s)
- Branden Cahill
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY, United States
| | - Samuel Poelker-Wells
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY, United States
| | - Jonathan F Prather
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY, United States
| | - Yun Li
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY, United States
| |
Collapse
|
9
|
Thumfart KM, Jawaid A, Bright K, Flachsmann M, Mansuy IM. Epigenetics of childhood trauma: Long term sequelae and potential for treatment. Neurosci Biobehav Rev 2021; 132:1049-1066. [PMID: 34742726 DOI: 10.1016/j.neubiorev.2021.10.042] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 10/17/2021] [Accepted: 10/29/2021] [Indexed: 12/17/2022]
Abstract
Childhood trauma (CT) can have persistent effects on the brain and is one of the major risk factors for neuropsychiatric diseases in adulthood. Recent advances in the field of epigenetics suggest that epigenetic factors such as DNA methylation and histone modifications, as well as regulatory processes involving non-coding RNA are associated with the long-term sequelae of CT. This narrative review summarizes current knowledge on the epigenetic basis of CT and describes studies in animal models and human subjects examining how the epigenome and transcriptome are modified by CT in the brain. It discusses psychological and pharmacological interventions that can counteract epigenetic changes induced by CT and the need to establish longitudinal assessment after CT for developing more effective diagnostics and treatment strategies based on epigenetic targets.
Collapse
Affiliation(s)
- Kristina M Thumfart
- Laboratory of Neuroepigenetics, Brain Research Institute, University of Zürich and Institute for Neuroscience of the Swiss Federal Institute of Technology, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland
| | - Ali Jawaid
- Laboratory of Neuroepigenetics, Brain Research Institute, University of Zürich and Institute for Neuroscience of the Swiss Federal Institute of Technology, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland; Laboratory for Translational Research in Neuropsychiatric Disorders (TREND), BRAINCITY: Center of Excellence for Neural Plasticity and Brain Disorders, Nencki Institute of Experimental Biology, Ludwika Pasteura 3, Warsaw, 02-093, Poland
| | - Kristina Bright
- Swiss Federal Institute of Technology Zurich, Zurich, Switzerland
| | - Marc Flachsmann
- Swiss Federal Institute of Technology Zurich, Zurich, Switzerland
| | - Isabelle M Mansuy
- Laboratory of Neuroepigenetics, Brain Research Institute, University of Zürich and Institute for Neuroscience of the Swiss Federal Institute of Technology, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland.
| |
Collapse
|
10
|
Hanson JL, Williams AV, Bangasser DA, Peña CJ. Impact of Early Life Stress on Reward Circuit Function and Regulation. Front Psychiatry 2021; 12:744690. [PMID: 34744836 PMCID: PMC8563782 DOI: 10.3389/fpsyt.2021.744690] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 09/21/2021] [Indexed: 12/15/2022] Open
Abstract
Early life stress - including experience of child maltreatment, neglect, separation from or loss of a parent, and other forms of adversity - increases lifetime risk of mood, anxiety, and substance use disorders. A major component of this risk may be early life stress-induced alterations in motivation and reward processing, mediated by changes in the nucleus accumbens (NAc) and ventral tegmental area (VTA). Here, we review evidence of the impact of early life stress on reward circuit structure and function from human and animal models, with a focus on the NAc. We then connect these results to emerging theoretical models about the indirect and direct impacts of early life stress on reward circuit development. Through this review and synthesis, we aim to highlight open research questions and suggest avenues of future study in service of basic science, as well as applied insights. Understanding how early life stress alters reward circuit development, function, and motivated behaviors is a critical first step toward developing the ability to predict, prevent, and treat stress-related psychopathology spanning mood, anxiety, and substance use disorders.
Collapse
Affiliation(s)
- Jamie L. Hanson
- Department of Psychology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Alexia V. Williams
- Department of Psychology and Neuroscience Program, Temple University, Philadelphia, PA, United States
| | - Debra A. Bangasser
- Department of Psychology and Neuroscience Program, Temple University, Philadelphia, PA, United States
| | - Catherine J. Peña
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, United States
| |
Collapse
|
11
|
Caputi FF, Carboni L, Rullo L, Alessandrini I, Balzani E, Melotti RM, Romualdi P, Candeletti S, Fanelli A. An Exploratory Pilot Study of Changes in Global DNA Methylation in Patients Undergoing Major Breast Surgery Under Opioid-Based General Anesthesia. Front Pharmacol 2021; 12:733577. [PMID: 34621169 PMCID: PMC8491974 DOI: 10.3389/fphar.2021.733577] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/06/2021] [Indexed: 12/30/2022] Open
Abstract
This study aimed to investigate DNA methylation levels in patients undergoing major breast surgery under opioid-based general anesthesia. Blood samples were collected from eleven enrolled patients, before, during and after anesthesia. PBMC were isolated and global DNA methylation levels as well as DNA methyltransferase (DNMT) and cytokine gene expression were assessed. DNA methylation levels significantly declined by 26%, reversing the direction after the end of surgery. Likewise, DNMT1a mRNA expression was significantly reduced at all time points, with lowest level of −68%. DNMT3a and DNMT3b decreased by 65 and 71%, respectively. Inflammatory cytokines IL6 and TNFα mRNA levels showed a trend for increased expression at early time-points to end with a significant decrease at 48 h after surgery. This exploratory study revealed for the first time intraoperative global DNA hypomethylation in patients undergoing major breast surgery under general anesthesia with fentanyl. The alterations of global DNA methylation here observed seem to be in agreement with DNMTs gene expression changes. Furthermore, based on perioperative variations of IL6 and TNFα gene expression, we hypothesize that DNA hypomethylation may occur as a response to surgical stress rather than to opiate exposure.
Collapse
Affiliation(s)
- Francesca Felicia Caputi
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Bologna, Italy
| | - Lucia Carboni
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Bologna, Italy
| | - Laura Rullo
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Bologna, Italy
| | - Irene Alessandrini
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Bologna, Italy
| | - Eleonora Balzani
- Department of Surgical Sciences, University of Turin, Turin, Italy
| | - Rita Maria Melotti
- Department of Surgical and Medical Sciences, Alma Mater Studiorum-University of Bologna, Bologna, Italy
| | - Patrizia Romualdi
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Bologna, Italy
| | - Sanzio Candeletti
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Bologna, Italy
| | - Andrea Fanelli
- Anesthesiology and Pain Therapy Unit, AOSP S.Orsola Hospital, Bologna, Italy
| |
Collapse
|
12
|
Abstract
Epigenetic mechanisms such as DNA methylation (DNAm) have been associated with stress responses and increased vulnerability to depression. Abnormal DNAm is observed in stressed animals and depressed individuals. Antidepressant treatment modulates DNAm levels and regulates gene expression in diverse tissues, including the brain and the blood. Therefore, DNAm could be a potential therapeutic target in depression. Here, we reviewed the current knowledge about the involvement of DNAm in the behavioural and molecular changes associated with stress exposure and depression. We also evaluated the possible use of DNAm changes as biomarkers of depression. Finally, we discussed current knowledge limitations and future perspectives.
Collapse
|
13
|
Laubach ZM, Greenberg JR, Turner JW, Montgomery TM, Pioon MO, Sawdy MA, Smale L, Cavalcante RG, Padmanabhan KR, Lalancette C, vonHoldt B, Faulk CD, Dolinoy DC, Holekamp KE, Perng W. Early-life social experience affects offspring DNA methylation and later life stress phenotype. Nat Commun 2021; 12:4398. [PMID: 34285226 PMCID: PMC8292380 DOI: 10.1038/s41467-021-24583-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 06/24/2021] [Indexed: 02/06/2023] Open
Abstract
Studies in rodents and captive primates suggest that the early-life social environment affects future phenotype, potentially through alterations to DNA methylation. Little is known of these associations in wild animals. In a wild population of spotted hyenas, we test the hypothesis that maternal care during the first year of life and social connectedness during two periods of early development leads to differences in DNA methylation and fecal glucocorticoid metabolites (fGCMs) later in life. Here we report that although maternal care and social connectedness during the den-dependent life stage are not associated with fGCMs, greater social connectedness during the subadult den-independent life stage is associated with lower adult fGCMs. Additionally, more maternal care and social connectedness after den independence correspond with higher global (%CCGG) DNA methylation. We also note differential DNA methylation near 5 genes involved in inflammation, immune response, and aging that may link maternal care with stress phenotype.
Collapse
Affiliation(s)
- Zachary M Laubach
- Department of Integrative Biology, Michigan State University, East Lansing, MI, USA.
- Program in Ecology, Evolution, and Behavior, Michigan State University, East Lansing, USA MI, USA.
- BEACON, NSF Center for the Study of Evolution in Action, Michigan State University, East Lansing, MI, USA.
- Mara Hyena Project, Masai Mara National Reserve, Narok, Kenya.
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA.
| | - Julia R Greenberg
- Department of Integrative Biology, Michigan State University, East Lansing, MI, USA
- Program in Ecology, Evolution, and Behavior, Michigan State University, East Lansing, USA MI, USA
- Mara Hyena Project, Masai Mara National Reserve, Narok, Kenya
| | - Julie W Turner
- Department of Integrative Biology, Michigan State University, East Lansing, MI, USA
- Program in Ecology, Evolution, and Behavior, Michigan State University, East Lansing, USA MI, USA
- BEACON, NSF Center for the Study of Evolution in Action, Michigan State University, East Lansing, MI, USA
- Mara Hyena Project, Masai Mara National Reserve, Narok, Kenya
| | - Tracy M Montgomery
- Department of Integrative Biology, Michigan State University, East Lansing, MI, USA
- Program in Ecology, Evolution, and Behavior, Michigan State University, East Lansing, USA MI, USA
- Mara Hyena Project, Masai Mara National Reserve, Narok, Kenya
- Max Planck Institute of Animal Behavior, Department for the Ecology of Animal Societies, Konstanz, Germany
| | - Malit O Pioon
- Mara Hyena Project, Masai Mara National Reserve, Narok, Kenya
| | - Maggie A Sawdy
- Department of Integrative Biology, Michigan State University, East Lansing, MI, USA
- Program in Ecology, Evolution, and Behavior, Michigan State University, East Lansing, USA MI, USA
| | - Laura Smale
- Department of Integrative Biology, Michigan State University, East Lansing, MI, USA
- Department of Psychology, Michigan State University, East Lansing, MI, USA
| | | | | | | | - Bridgett vonHoldt
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA
| | | | - Dana C Dolinoy
- Epigenomics Core, University of Michigan, Ann Arbor, MI, USA
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, MI, USA
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, MI, USA
| | - Kay E Holekamp
- Department of Integrative Biology, Michigan State University, East Lansing, MI, USA
- Program in Ecology, Evolution, and Behavior, Michigan State University, East Lansing, USA MI, USA
- BEACON, NSF Center for the Study of Evolution in Action, Michigan State University, East Lansing, MI, USA
- Mara Hyena Project, Masai Mara National Reserve, Narok, Kenya
| | - Wei Perng
- Department of Epidemiology and Lifecourse Epidemiology of Adiposity and Diabetes (LEAD) Center, University of Colorado Denver, Aurora, CO, USA
| |
Collapse
|
14
|
Sun H, Zhang X, Kong Y, Gou L, Lian B, Wang Y, Jiang L, Li Q, Sun H, Sun L. Maternal Separation-Induced Histone Acetylation Correlates with BDNF-Programmed Synaptic Changes in an Animal Model of PTSD with Sex Differences. Mol Neurobiol 2021; 58:1738-1754. [PMID: 33245480 DOI: 10.1007/s12035-020-02224-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 11/19/2020] [Indexed: 12/13/2022]
Abstract
Maternal separation (MS) causes long-lasting epigenetic changes in the brain and increases vulnerability to traumatic events in adulthood. Of interest, there may be sex-specific differences in these epigenetic changes. In this study, the extent of histone acetylation in the hippocampus (HIP) and the expression of BDNF were measured to determine whether BDNF influences risk of PTSD following MS in early life. Rat offspring were separated from their dams (3 h/day or 6 h/day from PND2~PND14). Then, pups were treated with a single prolonged stress (SPS) procedure when they reached adulthood (PND80). In animals stressed with the SPS procedure in adulthood, those that had increased MS intensity in childhood demonstrated more significant changes in performance on tests of anxiety, depression, and contextual fear memory. Reduced levels of total BDNF mRNA and protein were observed after SPS treatment and further declined in groups with greater MS time in childhood. Interestingly, these changes were correlated with decreased H3K9ac levels and increased HDAC2 levels. Additional MS also led to more severe ultrastructural synaptic damage in rats that experienced the SPS procedure, particularly in the CA1 and CA3 region of the HIP, reflecting impaired synaptic plasticity in these regions. Interestingly, male rats in the MS3h-PTSD group showed decreased anxiety, but no similar changes were found in female rats, suggesting a degree of gender specificity in coping with stress after mild MS. In summary, this study suggests that the epigenetic signatures of the BDNF genes can be linked to HIP responses to stress, providing insights that may be relevant for people at risk of stress-related psychopathologies.
Collapse
MESH Headings
- Acetylation
- Animals
- Behavior, Animal
- Brain-Derived Neurotrophic Factor/metabolism
- CA1 Region, Hippocampal/metabolism
- CA1 Region, Hippocampal/ultrastructure
- CA3 Region, Hippocampal/metabolism
- CA3 Region, Hippocampal/ultrastructure
- Corticosterone/blood
- Disease Models, Animal
- Elevated Plus Maze Test
- Fear
- Female
- Gene Expression Regulation
- Histone Deacetylase 2/genetics
- Histone Deacetylase 2/metabolism
- Histones/metabolism
- Immobilization
- Male
- Maternal Deprivation
- Open Field Test
- Rats, Sprague-Dawley
- Regression Analysis
- Sex Characteristics
- Stress Disorders, Post-Traumatic/blood
- Stress Disorders, Post-Traumatic/complications
- Stress Disorders, Post-Traumatic/metabolism
- Stress, Psychological/blood
- Stress, Psychological/complications
- Swimming
- Synapses/metabolism
- Synapses/ultrastructure
- Rats
Collapse
Affiliation(s)
- Haoran Sun
- School of Clinical Medicine, Weifang Medical University, 7166# Baotong West Street, Weifang, 261053, Shandong, People's Republic of China
| | - Xianqiang Zhang
- School of Psychology, Weifang Medical University, 7166# Baotong West Street, Weifang, 261053, Shandong, People's Republic of China
- National Clinical Research Center for Mental Disorders, Peking University Sixth Hospital/Institute of Mental Health and the Key Laboratory of Mental Health, Ministry of Health (Peking University), Beijing, 100083, People's Republic of China
| | - Yujia Kong
- School of Public Health, Weifang Medical University, 7166# Baotong West Street, Weifang, 261053, Shandong, People's Republic of China
| | - Luping Gou
- School of Psychology, Weifang Medical University, 7166# Baotong West Street, Weifang, 261053, Shandong, People's Republic of China
| | - Bo Lian
- School of Bioscience and Technology, Weifang Medical University, 7166# Baotong West Street, Weifang, 261053, Shandong, People's Republic of China
| | - Yanyu Wang
- School of Psychology, Weifang Medical University, 7166# Baotong West Street, Weifang, 261053, Shandong, People's Republic of China
| | - Li Jiang
- Cerebral Center, Sunshine Union Hospital, 9000# Yingqian Street, Weifang, 261205, Shandong, People's Republic of China
| | - Qi Li
- Department of Psychiatry and Centre for Reproduction Growth and Development, University of Hong Kong, Hong Kong, People's Republic of China
| | - Hongwei Sun
- School of Psychology, Weifang Medical University, 7166# Baotong West Street, Weifang, 261053, Shandong, People's Republic of China
| | - Lin Sun
- School of Psychology, Weifang Medical University, 7166# Baotong West Street, Weifang, 261053, Shandong, People's Republic of China.
| |
Collapse
|
15
|
Castro‐Zavala A, Martín‐Sánchez A, Luján MÁ, Valverde O. Maternal separation increases cocaine intake through a mechanism involving plasticity in glutamate signalling. Addict Biol 2021; 26:e12911. [PMID: 32329565 DOI: 10.1111/adb.12911] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 04/05/2020] [Accepted: 04/08/2020] [Indexed: 12/16/2022]
Abstract
Early-life stress (ELS) is associated with negative consequences, including maladaptive long-lasting brain effects. These alterations seem to increase the likelihood of developing substance use disorders. However, the molecular consequences of ELS are poorly understood. In the present study, we tested the impact of ELS induced by maternal separation with early weaning (MSEW) in CD1 male mice at different phases of cocaine self-administration (SA). We also investigated the subsequent alterations on GluR2, GluR1, cAMP response element-binding (CREB), and CREB-phosphorylation (pCREB) in ventral tegmental area (VTA) and nucleus accumbens (NAc) induced by both MSEW and cocaine SA. Our results show that MSEW animals expressed a higher cocaine intake, an increased vulnerability to the acquisition of cocaine SA, and incapacity to extinguish cocaine SA behaviour. MSEW mice showed decreased GluR2 and increased GluR1 and pCREB in NAc. Also, results displayed reduction of basal levels of GluR1 and CREB and an elevation of GluR1/GluR2 ratio in the VTA. Such results hint at an enhanced glutamatergic function in NAc and increased excitability of VTA DA neurons in maternally separated mice. Altogether, our results suggest that MSEW induces molecular alterations in the brain areas related to reward processing, increasing the vulnerability to depression and cocaine-seeking behaviour.
Collapse
Affiliation(s)
- Adriana Castro‐Zavala
- Neurobiology of Behaviour Research Group (GReNeC‐NeuroBio), Department of Experimental and Health Sciences Universitat Pompeu Fabra Barcelona Spain
| | - Ana Martín‐Sánchez
- Neurobiology of Behaviour Research Group (GReNeC‐NeuroBio), Department of Experimental and Health Sciences Universitat Pompeu Fabra Barcelona Spain
- Neuroscience Research Programme IMIM‐Hospital del Mar Research Institute Barcelona Spain
| | - Miguel Ángel Luján
- Neurobiology of Behaviour Research Group (GReNeC‐NeuroBio), Department of Experimental and Health Sciences Universitat Pompeu Fabra Barcelona Spain
| | - Olga Valverde
- Neurobiology of Behaviour Research Group (GReNeC‐NeuroBio), Department of Experimental and Health Sciences Universitat Pompeu Fabra Barcelona Spain
- Neuroscience Research Programme IMIM‐Hospital del Mar Research Institute Barcelona Spain
| |
Collapse
|
16
|
Catale C, Bussone S, Lo Iacono L, Viscomi MT, Palacios D, Troisi A, Carola V. Exposure to different early-life stress experiences results in differentially altered DNA methylation in the brain and immune system. Neurobiol Stress 2020; 13:100249. [PMID: 33344704 PMCID: PMC7739045 DOI: 10.1016/j.ynstr.2020.100249] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/15/2020] [Accepted: 08/26/2020] [Indexed: 12/11/2022] Open
Abstract
The existence of a proportional relationship between the number of early-life stress (ELS) events experienced and the impoverishment of child mental health has been hypothesized. However, different types of ELS experiences may be associated with different neuro-psycho-biological impacts, due to differences in the intrinsic nature of the stress. DNA methylation is one of the molecular mechanisms that have been implicated in the "translation" of ELS exposure into neurobiological and behavioral abnormalities during adulthood. Here, we investigated whether different ELS experiences resulted in differential impacts on global DNA methylation levels in the brain and blood samples from mice and humans. ELS exposure in mice resulted in observable changes in adulthood, with exposure to social isolation inducing more dramatic alterations in global DNA methylation levels in several brain structures compared with exposure to a social threatening environment. Moreover, these two types of stress resulted in differential impacts on the epigenetic programming of different brain regions and cellular populations, namely microglia. In a pilot clinical study, blood global DNA methylation levels and exposure to childhood neglect or abuse were investigated in patients presenting with major depressive disorder or substance use disorder. A significant effect of the mental health diagnosis on global methylation levels was observed, but no effect of either childhood abuse or neglect was detected. These findings demonstrate that different types of ELS have differential impacts on epigenetic programming, through DNA methylation in specific brain regions, and that these differential impacts are associated with the different behavioral outcomes observed after ELS experiences.
Collapse
Affiliation(s)
- Clarissa Catale
- Department of Psychology, Ph.D. Program in "Behavioral Neuroscience", Sapienza University of Rome, Rome, Italy
| | - Silvia Bussone
- Department of Dynamic and Clinical Psychology, Sapienza University of Rome, Rome, Italy
| | - Luisa Lo Iacono
- Department of Psychology, Sapienza University of Rome, Rome, Italy.,IRCCS Santa Lucia Foundation, Rome, Italy
| | - Maria Teresa Viscomi
- Department of Life Science and Public Health, Section of Histology and Embryology, University "Cattolica Del S. Cuore", Rome, Italy
| | | | - Alfonso Troisi
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Valeria Carola
- Department of Dynamic and Clinical Psychology, Sapienza University of Rome, Rome, Italy.,IRCCS Santa Lucia Foundation, Rome, Italy
| |
Collapse
|
17
|
Cocaine-induced inheritable epigenetic marks may be altered by changing early postnatal fostering. Neuroreport 2020; 30:1157-1165. [PMID: 31568187 DOI: 10.1097/wnr.0000000000001332] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Here, we explored the hypothesis that parental cocaine exposure could alter epigenetic machinery in their drug-naive offspring while early postnatal fostering may further modify the accompanied neurochemical and functional components. Variant drug-naive pups were produced from cocaine-exposed or unexposed C57BL/6 female mice that were matched with their male counterparts for mating. Within 3 days of birth, half of the pups were cross-fostered and nurtured by non-biological lactating dams. The pups were initially examined for locomotor activity and memory performance and subsequently for changes in DNA methylation in promoter regions of cAMP response element modulator (Crem) and Fosb in the prefrontal cortex at 48 days postnatum. The impact of postnatal fostering on these parameters was also investigated. Our results showed that cocaine exposure significantly decreased both Crem and Fosb methylation in the prefrontal cortex of progenitor mice, while similar patterns of methylation were replicated in the brains of drug-naive non-fostered offspring mice but reversed by postnatal fostering. Furthermore, offspring raised by cocaine-exposed dams were impaired in discriminative learning and exhibited memory decline, whereas locomotor activity remains unaltered in all groups of mice. Our data provide some evidence that indirect exposure to cocaine may cause marked epigenetic changes within the cortical networks of drug-naive descendants and that mediation by Crem/Fosb signalling in this brain region may be beneficial, while early postnatal fostering may further engineer molecular switching that may predispose the individual to future risky behaviours as well as accumulative potential to developing cognitive impairment later in life.
Collapse
|
18
|
Vaher K, Anier K, Jürgenson M, Harro J, Kalda A. Cocaine-induced changes in behaviour and DNA methylation in rats are influenced by inter-individual differences in spontaneous exploratory activity. J Psychopharmacol 2020; 34:680-692. [PMID: 32338111 DOI: 10.1177/0269881120916137] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
BACKGROUND Individual differences in behavioural traits influence susceptibility to addictive disorders. Drug addiction involves changes in gene expression, proposed to occur via DNA methylation (DNAm). AIMS To investigate DNAm changes in reward-related brain structures (nucleus accumbens (NAc), lateral habenula (LHb)) in response to cocaine exposure in rats differing in spontaneous exploratory activity. METHODS Rats were observed in the exploration box and categorised as high- (HE) or low explorers (LE). Rats were administered vehicle or cocaine (12 mg/kg, i.p.) for 7 days, followed by a 14-day withdrawal period and cocaine challenge (7 mg/kg); horizontal locomotor activity was recorded. Brain tissue was dissected after 24 h; we analysed messenger RNA (mRNA) and activity levels of epigenetic DNA modifiers (DNMTs and TETs) as well as mRNA and promoter methylation levels at selected genes previously linked to addictive behaviours. RESULTS The cocaine challenge dose stimulated locomotor activity in both LE- and HE rats only when administered after a repeated cocaine schedule, suggesting development of behavioural sensitisation. Quantitative polymerase chain reaction analyses demonstrated higher basal expression of Dnmt3a, Tet2 and Tet3 in the LHb of HE- vs. LE rats, and we observed differential effects of cocaine exposure on the expression and activity of epigenetic DNA modifiers in the NAc and LHb of HE- and LE rats. Furthermore, cocaine exposure differentially altered promoter methylation levels of A2AR, Ppp1cc, and Taar7b in the NAc and LHb of HE- and LE rats. CONCLUSIONS DNAm might play a role in the HE- and LE phenotypes as well as mediate behavioural effects of LE- and HE rats in response to drugs of abuse.
Collapse
Affiliation(s)
- Kadi Vaher
- Department of Psychology, University of Tartu, Tartu, Estonia
| | - Kaili Anier
- Department of Pharmacology, University of Tartu, Tartu, Estonia
| | | | - Jaanus Harro
- Department of Psychology, University of Tartu, Tartu, Estonia
| | - Anti Kalda
- Department of Pharmacology, University of Tartu, Tartu, Estonia
| |
Collapse
|
19
|
Leichtweis KS, Carvalho M, Morais-Silva G, Marin MT, Amaral VCS. Short and prolonged maternal separation impacts on ethanol-related behaviors in rats: sex and age differences. Stress 2020; 23:162-173. [PMID: 31429361 DOI: 10.1080/10253890.2019.1653847] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Maternal separation (MS) is an animal model widely used to evaluate the influence of early-life stress exposure on ethanol consumption and dependence. The goal of this study was to evaluate the effects of brief and prolonged MS on the pattern of consumption and ethanol conditioned place preference (CPP) in male and female rats during adolescence and adulthood. Wistar rat pups were separated daily from their dams for 15 or 180 minutes during the 2 to 10 postnatal days (PND). In adolescence, half of the litter from each group was evaluated in the ethanol consumption test using the three-bottle test choice paradigm. In addition, using biased procedure, ethanol-conditioned place preference was also evaluated. In adulthood, the other half of the litter was evaluated on the same tests. Our results showed that there are differences in consumption pattern and in alcohol reinforcement between males and females, adolescents and adults. While prolonged MS had no effect on total ethanol consumption in adolescents of both sexes, it induced CPP in these animals. In turn, in adults, previous exposure to prolonged MS increased ethanol consumption without altering ethanol-CPP.Lay summaryGiving the importance of the mother-children (dam-pups when talking about rodents) relationship to proper brain development, the separation of pups from their dam is broadly used as an animal model to study the impact of early-life stress exposure. Here, we used a protocol of brief or prolonged maternal separation to study the impact of early-life stress exposure in the alcohol consumption and conditioned place preference in rats, and how age and sex influence it. We showed that, overall, the prolonged maternal separation increased alcohol consumption in both males and females, but only when animals were tested during the adulthood. In the other hand, prolonged maternal separation increased ethanol conditioned place preference in adolescent rats, both male and female.
Collapse
Affiliation(s)
- Kamila Souto Leichtweis
- Programa de Pós-Graduação Stricto Sensu em Ciências Aplicadas a Produtos para Saúde (PPGCAPS), Universidade Estadual de Goiás, Anápolis, Brasil
| | - Marielly Carvalho
- Programa de Pós-Graduação Stricto Sensu em Ciências Aplicadas a Produtos para Saúde (PPGCAPS), Universidade Estadual de Goiás, Anápolis, Brasil
| | - Gessynger Morais-Silva
- Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista (Unesp), Araraquara, Brasil
- Programa Interinstitucional de Pós-Graduação em Ciências Fisiológicas, Universidade Federal de São Carlos/Universidade Estadual Paulista (UFSCar/UNESP), São Carlos, Brasil
| | - Marcelo Tadeu Marin
- Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista (Unesp), Araraquara, Brasil
- Programa Interinstitucional de Pós-Graduação em Ciências Fisiológicas, Universidade Federal de São Carlos/Universidade Estadual Paulista (UFSCar/UNESP), São Carlos, Brasil
| | - Vanessa Cristiane Santana Amaral
- Programa de Pós-Graduação Stricto Sensu em Ciências Aplicadas a Produtos para Saúde (PPGCAPS), Universidade Estadual de Goiás, Anápolis, Brasil
- Campus Anápolis de Ciências Exatas e Tecnológicas Henrique Santillo (CCET), Universidade Estadual de Goiás, Anápolis, Brasil
| |
Collapse
|
20
|
María-Ríos CE, Morrow JD. Mechanisms of Shared Vulnerability to Post-traumatic Stress Disorder and Substance Use Disorders. Front Behav Neurosci 2020; 14:6. [PMID: 32082127 PMCID: PMC7006033 DOI: 10.3389/fnbeh.2020.00006] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 01/13/2020] [Indexed: 12/11/2022] Open
Abstract
Psychoactive substance use is a nearly universal human behavior, but a significant minority of people who use addictive substances will go on to develop an addictive disorder. Similarly, though ~90% of people experience traumatic events in their lifetime, only ~10% ever develop post-traumatic stress disorder (PTSD). Substance use disorders (SUD) and PTSD are highly comorbid, occurring in the same individual far more often than would be predicted by chance given the respective prevalence of each disorder. Some possible reasons that have been proposed for the relationship between PTSD and SUD are self-medication of anxiety with drugs or alcohol, increased exposure to traumatic events due to activities involved in acquiring illegal substances, or addictive substances altering the brain's stress response systems to make users more vulnerable to PTSD. Yet another possibility is that some people have an intrinsic vulnerability that predisposes them to both PTSD and SUD. In this review, we integrate clinical and animal data to explore these possible etiological links between SUD and PTSD, with an emphasis on interactions between dopaminergic, adrenocorticotropic, GABAergic, and glutamatergic neurobehavioral mechanisms that underlie different emotional learning styles.
Collapse
Affiliation(s)
| | - Jonathan D. Morrow
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, United States
- Department of Psychiatry, University of Michigan, Ann Arbor, MI, United States
| |
Collapse
|
21
|
Impact of Maternal Separation on Dopamine System and its Association with Parkinson's Disease. Neuromolecular Med 2020; 22:335-340. [PMID: 31933131 DOI: 10.1007/s12017-019-08587-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 12/25/2019] [Indexed: 01/09/2023]
Abstract
As a type of stress, maternal separation (MS) has been one of the most widely used models in neuropsychiatric research. An increasing number of studies has found that MS not only affects the function of the hypothalamic-pituitary-adrenal axis and hippocampal 5-hydroxytryptamine system, but also causes dysfunction of the central dopamine (DA) system and increases the susceptibility of dopaminergic neurons to pathogenic factors of Parkinson's disease (PD), for instance, 6-hydroxydopamine, thus impairing motor function. We reviewed the impact of MS on the DA system and its correlation with PD and found the following: (1) discrepant effects of MS on the DA system have been reported; (2) MS is a good model to study the impact of stress on the occurrence and development of PD, however, unified modeling criteria of MS are required; (3) correlation between MS and PD may involve the impact of MS on the DA system, which however is not the only connection; (4) intervening measures can block pathways between MS and PD, which provides reference for the prevention of PD in specific populations such as left-behind children.
Collapse
|
22
|
Abstract
Depression is one of the most common psychiatric disorders affecting public health. Studies over the past years suggest that the methylations of some specific genes such as BDNF, SLC6A4, and NR3C1 play an important role in the development of depression. Recently, epigenetic evidences suggest that the expression levels of DNA methyltransferases differ in several brain areas including the prefrontal cortex, hippocampus, amygdala, and nucleus accumbens in depression patients and animal models, but the potential link between the expression levels of DNA methylatransferases and the methylations of specific genes needs further investigation to clarify the pathogenesis of depression.
Collapse
Affiliation(s)
- Zhenghao Duan
- Department of Human Anatomy, College of Basic Medical Sciences, China Medical University, Shenyang, China.,Department of Neurology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Jie Lu
- Department of Human Anatomy, College of Basic Medical Sciences, China Medical University, Shenyang, China
| |
Collapse
|
23
|
White JD, Kaffman A. The Moderating Effects of Sex on Consequences of Childhood Maltreatment: From Clinical Studies to Animal Models. Front Neurosci 2019; 13:1082. [PMID: 31680821 PMCID: PMC6797834 DOI: 10.3389/fnins.2019.01082] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 09/25/2019] [Indexed: 12/12/2022] Open
Abstract
Stress has pronounced effects on the brain, and thus behavioral outputs. This is particularly true when the stress occurs during vulnerable points in development. A review of the clinical literature regarding the moderating effects of sex on psychopathology in individuals exposed to childhood maltreatment (CM) is complicated by a host of variables that are difficult to quantify and control in clinical settings. As a result, the precise role of sex in moderating the consequences of CM remains elusive. In this review, we explore the rationale for studying this important question and their implications for treatment. We examine this issue using the threat/deprivation conceptual framework and highlight a growing body of work demonstrating important sex differences in human studies and in animal models of early life stress (ELS). The challenges and obstacles for effectively studying this question are reviewed and are followed by recommendations on how to move forward at the clinical and preclinical settings. We hope that this review will help inspire additional studies on this important topic.
Collapse
Affiliation(s)
- Jordon D White
- Department of Psychiatry, Yale School of Medicine, Yale University, New Haven, CT, United States
| | - Arie Kaffman
- Department of Psychiatry, Yale School of Medicine, Yale University, New Haven, CT, United States
| |
Collapse
|
24
|
Bendre M, Granholm L, Drennan R, Meyer A, Yan L, Nilsson KW, Nylander I, Comasco E. Early life stress and voluntary alcohol consumption in relation to Maoa methylation in male rats. Alcohol 2019; 79:7-16. [PMID: 30414913 DOI: 10.1016/j.alcohol.2018.11.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 10/30/2018] [Accepted: 11/01/2018] [Indexed: 01/22/2023]
Abstract
Early life stress (ELS) or alcohol consumption can influence DNA methylation and affect gene expression. Monoamine oxidase A (Maoa) encodes the enzyme that metabolizes monoaminergic neurotransmitters crucial for the stress response, alcohol reward, and reinforcement. Previously, we reported lower Maoa expression in the nucleus accumbens and dorsal striatum of male rats exposed to ELS during the first three postnatal weeks, and to voluntary alcohol consumption in adulthood, compared with controls. The present study continued to investigate the effect of ELS and alcohol consumption on Maoa methylation, and its relation to Maoa expression in these animals. We selected candidate CpGs after performing next-generation bisulfite sequencing of the Maoa promoter, intron 1-5, and exons 5 and 6, together composed of 107 CpGs (5'-cytosine-phosphate-guanosine-3'), in a subgroup of rats. Pyrosequencing was used to analyze the methylation of 10 candidate CpGs in the promoter and intron 1 in the entire sample. ELS and alcohol displayed an interactive effect on CpG-specific methylation in the dorsal striatum. CpG-specific methylation correlated with Maoa expression, corticosterone levels, and alcohol consumption in a brain region-specific manner. CpG-specific methylation in the Maoa promoter was a potential moderator of the interaction of ELS with alcohol consumption on Maoa expression in the NAc. However, the findings were sparse, did not survive correction for multiple testing, and the magnitude of differences in methylation levels was small. In conclusion, CpG-specific Maoa methylation in the promoter and intron 1 may associate with ELS, alcohol consumption, and Maoa expression in reward-related brain regions.
Collapse
|
25
|
Keller SM, Doherty TS, Roth TL. Pharmacological manipulation of DNA methylation normalizes maternal behavior, DNA methylation, and gene expression in dams with a history of maltreatment. Sci Rep 2019; 9:10253. [PMID: 31311968 PMCID: PMC6635500 DOI: 10.1038/s41598-019-46539-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 06/25/2019] [Indexed: 01/02/2023] Open
Abstract
The quality of parental care received during development profoundly influences an individual's phenotype, including that of maternal behavior. We previously found that female rats with a history of maltreatment during infancy mistreat their own offspring. One proposed mechanism through which early-life experiences influence behavior is via epigenetic modifications. Indeed, our lab has identified a number of brain epigenetic alterations in female rats with a history of maltreatment. Here we sought to investigate the role of DNA methylation in aberrant maternal behavior. We administered zebularine, a drug known to alter DNA methylation, to dams exposed during infancy to the scarcity-adversity model of low nesting resources, and then characterized the quality of their care towards their offspring. First, we replicate that dams with a history of maltreatment mistreat their own offspring. Second, we show that maltreated-dams treated with zebularine exhibit lower levels of adverse care toward their offspring. Third, we show that administration of zebularine in control dams (history of nurturing care) enhances levels of adverse care. Lastly, we show altered methylation and gene expression in maltreated dams normalized by zebularine. These findings lend support to the hypothesis that epigenetic alterations resulting from maltreatment causally relate to behavioral outcomes.
Collapse
Affiliation(s)
- Samantha M Keller
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE, 19716, USA
| | - Tiffany S Doherty
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE, 19716, USA
| | - Tania L Roth
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE, 19716, USA.
| |
Collapse
|
26
|
Early life stress and the propensity to develop addictive behaviors. Int J Dev Neurosci 2019; 78:156-169. [PMID: 31255718 DOI: 10.1016/j.ijdevneu.2019.06.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 06/03/2019] [Accepted: 06/13/2019] [Indexed: 12/14/2022] Open
Abstract
There is a vast literature on effects of early life manipulations in rodents much of which is aimed at investigating the long-term consequences related to emotion and cognition in adulthood. Less is known about how these manipulations affect responses reflective of alcohol (AUD) and substance (SUD) use disorders. The purpose of this paper is to review the literature of studies that employed early life manipulations and assessed behavioral responses to psychoactive substances, specifically alcohol, opiates, and stimulants, in rodents. While the findings with alcohol are more limited and mixed, studies with opiates and stimulants show strong support for the ability of these manipulations to enhance behavioral responsivity to these substances in line with epidemiological data. Some outcomes show sex differences. The mechanisms that influence these enduring changes may reflect epigenetic alterations. Several studies support a role for altered DNA methylation (and other epigenetic mechanisms) as biological responses to early environmental insults. The chemical changes induced by DNA methylation affect transcriptional activity of DNA and thus can have a long-term impact on the individual's phenotype. Such effects are particularly robust when they occur during sensitive periods of brain development (e.g., first postnatal weeks in rodents). We review this emerging literature as it relates to the known neurobiology of AUDs and SUDs and suggest new avenues of research. Such findings will have implications for the treatment and prevention of AUDs and SUDs and could provide insight into factors that support resiliency.
Collapse
|
27
|
Urb M, Anier K, Matsalu T, Aonurm-Helm A, Tasa G, Koppel I, Zharkovsky A, Timmusk T, Kalda A. Glucocorticoid Receptor Stimulation Resulting from Early Life Stress Affects Expression of DNA Methyltransferases in Rat Prefrontal Cortex. J Mol Neurosci 2019; 68:99-110. [PMID: 30852742 DOI: 10.1007/s12031-019-01286-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Accepted: 02/25/2019] [Indexed: 12/14/2022]
Abstract
Early life stress initiates long-term neurobiological changes that affect stress resilience and increased susceptibility to psychopathology. Maternal separation (MS) is used to cause early life stress and it induces profound neurochemical and behavioral changes that last until adulthood. The molecular pathways of how MS affects the regulation of DNA methyltransferases (Dnmt) in brain have not been entirely characterized. We evaluated MS effects on Dnmt1, Dnmt3a and Dnmt3b expression, DNMT enzyme activity and glucocorticoid receptor (GR) recruitment to different Dnmt loci in the prefrontal cortex (PFC) of Wistar rats. We found increased plasma corticosterone levels after MS that were associated with induced Dnmt expression and enzyme activity in rat PFC at post-natal day 15 (PND15). Chromatin immunoprecipitation showed increased binding of GR at the Dnmt3b promoter after MS, suggesting that genomic signaling of GR is an important regulatory mechanism for the induced Dnmt3b expression and DNMT activity. Although GR also binds to Dnmt3a promoter and a putative regulatory region in intron 3 in rat PFC, its expression after maternal separation may be influenced by other mechanisms. Therefore, GR could be a link between early life stress experience and long-term gene expression changes induced by aberrant DNA methylation.
Collapse
Affiliation(s)
- Mari Urb
- Department of Pharmacology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
| | - Kaili Anier
- Department of Pharmacology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
| | - Terje Matsalu
- Department of Pharmacology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
| | - Anu Aonurm-Helm
- Department of Pharmacology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
| | - Gunnar Tasa
- Department of Human Biology and Genetics, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Indrek Koppel
- Institute of Chemistry and Biotechnology, Tallinn University of Technology, Tallinn, Estonia.,Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Alexander Zharkovsky
- Department of Pharmacology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
| | - Tõnis Timmusk
- Institute of Chemistry and Biotechnology, Tallinn University of Technology, Tallinn, Estonia
| | - Anti Kalda
- Department of Pharmacology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia.
| |
Collapse
|
28
|
Kahl KG, Stapel B, Frieling H. Link between depression and cardiovascular diseases due to epigenomics and proteomics: Focus on energy metabolism. Prog Neuropsychopharmacol Biol Psychiatry 2019; 89:146-157. [PMID: 30194950 DOI: 10.1016/j.pnpbp.2018.09.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 08/13/2018] [Accepted: 09/05/2018] [Indexed: 12/11/2022]
Abstract
Major depression is the most common mental disorder and a leading cause of years lived with disability. In addition to the burden attributed to depressive symptoms and reduced daily life functioning, people with major depression are at increased risk of premature mortality, particularly due to cardiovascular diseases. Several studies point to a bi-directional relation between major depression and cardiovascular diseases, thereby indicating that both diseases may share common pathophysiological pathways. These include lifestyle factors (e.g. physical activity, smoking behavior), dysfunctions of endocrine systems (e.g. hypothalamus-pituitary adrenal axis), and a dysbalance of pro- and anti-inflammatory factors. Furthermore, recent research point to the role of epigenomic and proteomic factors, that are reviewed here with a particular focus on the mitochondrial energy metabolism.
Collapse
Affiliation(s)
- Kai G Kahl
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Germany.
| | - Britta Stapel
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Germany
| | - Helge Frieling
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Germany
| |
Collapse
|
29
|
Social Behaviour and Epigenetic Status in Adolescent and Adult Rats: The Contribution of Early-Life Stressful Social Experience. Cell Mol Neurobiol 2019; 39:371-385. [DOI: 10.1007/s10571-019-00655-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 01/24/2019] [Indexed: 01/14/2023]
|
30
|
Di Segni M, Andolina D, Ventura R. Long-term effects of early environment on the brain: Lesson from rodent models. Semin Cell Dev Biol 2018; 77:81-92. [DOI: 10.1016/j.semcdb.2017.09.039] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 09/20/2017] [Accepted: 09/29/2017] [Indexed: 12/21/2022]
|
31
|
Burns SB, Szyszkowicz JK, Luheshi GN, Lutz PE, Turecki G. Plasticity of the epigenome during early-life stress. Semin Cell Dev Biol 2018; 77:115-132. [DOI: 10.1016/j.semcdb.2017.09.033] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Revised: 09/08/2017] [Accepted: 09/22/2017] [Indexed: 12/22/2022]
|
32
|
Epigenetic mechanisms associated with addiction-related behavioural effects of nicotine and/or cocaine: implication of the endocannabinoid system. Behav Pharmacol 2018; 28:493-511. [PMID: 28704272 DOI: 10.1097/fbp.0000000000000326] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The addictive use of nicotine (NC) and cocaine (COC) continues to be a major public health problem, and their combined use has been reported, particularly during adolescence. In neural plasticity, commonly induced by NC and COC, as well as behavioural plasticity related to the use of these two drugs, the involvement of epigenetic mechanisms, in which the reversible regulation of gene expression occurs independently of the DNA sequence, has recently been reported. Furthermore, on the basis of intense interactions with the target neurotransmitter systems, the endocannabinoid (ECB) system has been considered pivotal for eliciting the effects of NC or COC. The combined use of marijuana with NC and/or COC has also been reported. This article presents the addiction-related behavioural effects of NC and/or COC, based on the common behavioural/neural plasticity and combined use of NC/COC, and reviews the interacting role of the ECB system. The epigenetic processes inseparable from the effects of NC and/or COC (i.e. DNA methylation, histone modifications and alterations in microRNAs) and the putative therapeutic involvement of the ECB system at the epigenetic level are also discussed.
Collapse
|
33
|
Scott D, Tamminga CA. Effects of genetic and environmental risk for schizophrenia on hippocampal activity and psychosis-like behavior in mice. Behav Brain Res 2018; 339:114-123. [PMID: 29155005 DOI: 10.1016/j.bbr.2017.10.039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 10/27/2017] [Accepted: 10/31/2017] [Indexed: 10/18/2022]
Abstract
Schizophrenia is a serious mental illness most notably characterized by psychotic symptoms. In humans, psychotic disorders are associated with specific hippocampal pathology. However, animal model systems for psychosis often lack this pathology, and have been weak in providing a representation of psychosis. We utilized a double-risk model system combining genetic risk with environmental stress. We hypothesized these factors will induce hippocampal subfield pathology consistent with human findings, as well as behavioral phenotypes relevant to psychosis. To address this, we exposed wild-type and transgenic Disc1 dominant negative (Disc1-deficient) mice to maternal deprivation. In adulthood, hippocampal subfields were examined for signs of cellular and behavioral pathology associated with psychosis. Mice exposed to maternal deprivation showed a decrease in dentate gyrus activity, and an increase in CA3/CA1 activity. Furthermore, results demonstrated a differential behavioral effect between maternal deprivation and Disc1 deficiency, with maternal deprivation associated with a hyperactive phenotype and impaired prepulse inhibition, and Disc1 deficiency causing an impairment in fear conditioning. These results suggest distinct consequences of environmental and genetic risk factors contributing to psychosis, with maternal deprivation inducing a state more wholly consistent with schizophrenia psychosis. Further research is needed to determine if this pathology is causally related to a specific behavioral phenotype. The development of a strong inference animal model system for psychosis would satisfy a high medical need in schizophrenia research.
Collapse
Affiliation(s)
- Daniel Scott
- Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas TX, 75390-9127, United States.
| | - Carol A Tamminga
- Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas TX, 75390-9127, United States
| |
Collapse
|
34
|
Effects of adolescent social stress and antidepressant treatment on cognitive inflexibility and Bdnf epigenetic modifications in the mPFC of adult mice. Psychoneuroendocrinology 2018; 88:92-101. [PMID: 29195162 DOI: 10.1016/j.psyneuen.2017.11.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 11/22/2017] [Accepted: 11/25/2017] [Indexed: 12/17/2022]
Abstract
Adolescent social stress (ASS) can increase susceptibility to depression in adulthood. However, the underlying psychological and neural mechanisms remain unclear. Cortically mediated cognitive dysfunctions are increasingly recognized as an independent and important risk factor of depression. Using social defeat stress, a classical animal model of depression, our previous studies found that mice subjected to this form of stress during early adolescence displayed cognitive inflexibility (CI) in adulthood. This change was accompanied by a down-regulation of Bdnf gene expression in the medial prefrontal cortex (mPFC); this gene encodes a key molecule involved in depression and antidepressant action. In the present paper, we identified epigenetic modification of Bdnf as a possible mechanism underlying the behavioral and molecular changes. ASS induced a set of depressive phenotypes, including increased social avoidance and CI, as well as reduced levels of total Bdnf and isoform IV but not isoform I or VI transcripts in the mPFC. In parallel with changes in Bdnf gene expression, previously stressed adult mice showed increased levels of dimethylation of histone H3 at lysine K9 (H3K9me2) immediately downstream of the Bdnf IV promoter. On the other hand, no differences were found in trimethylation of histone H3 at lysine K4 (H3K4me3) or in acetylation of histone H3 at lysine K9 (H3K9ac) or at K4 (H3K4ac) in the Bdnf IV promoter. Likewise, no alterations were found in DNA methylation of the Bdnf IV promoter. Additionally, treatment with the chronic antidepressant tranylcypromine reversed Bdnf epigenetic changes and related gene transcription while also reversing CI, but not social avoidance, in previously stressed adult mice. These results suggest that epigenetic changes to the Bdnf gene in the mPFC after adolescent social adversity may be involved in the regulation of cognitive dysfunction in depression and antidepressant action in adulthood.
Collapse
|
35
|
Boschen KE, Keller SM, Roth TL, Klintsova AY. Epigenetic mechanisms in alcohol- and adversity-induced developmental origins of neurobehavioral functioning. Neurotoxicol Teratol 2018; 66:63-79. [PMID: 29305195 DOI: 10.1016/j.ntt.2017.12.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 12/11/2017] [Accepted: 12/26/2017] [Indexed: 12/13/2022]
Abstract
The long-term effects of developmental alcohol and stress exposure are well documented in both humans and non-human animal models. Damage to the brain and attendant life-long impairments in cognition and increased risk for psychiatric disorders are debilitating consequences of developmental exposure to alcohol and/or psychological stress. Here we discuss evidence for a role of epigenetic mechanisms in mediating these consequences. While we highlight some of the common ways in which stress or alcohol impact the epigenome, we point out that little is understood of the epigenome's response to experiencing both stress and alcohol exposure, though stress is a contributing factor as to why women drink during pregnancy. Advancing our understanding of this relationship is of critical concern not just for the health and well-being of individuals directly exposed to these teratogens, but for generations to come.
Collapse
Affiliation(s)
- K E Boschen
- Bowles Center for Alcohol Studies, University of North Carolina, Chapel Hill, NC 27599, United States
| | - S M Keller
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716, United States
| | - T L Roth
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716, United States.
| | - A Y Klintsova
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716, United States.
| |
Collapse
|
36
|
Barnett Burns S, Almeida D, Turecki G. The Epigenetics of Early Life Adversity: Current Limitations and Possible Solutions. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2018; 157:343-425. [DOI: 10.1016/bs.pmbts.2018.01.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
37
|
Doherty TS, Blaze J, Keller SM, Roth TL. Phenotypic outcomes in adolescence and adulthood in the scarcity-adversity model of low nesting resources outside the home cage. Dev Psychobiol 2017; 59:703-714. [PMID: 28767135 PMCID: PMC5569321 DOI: 10.1002/dev.21547] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 06/27/2017] [Indexed: 01/10/2023]
Abstract
Early life adversity is known to disrupt behavioral trajectories and many rodent models have been developed to characterize these stress-induced outcomes. One example is the scarcity-adversity model of low nesting resources. This model employs resource scarcity (i.e., low nesting materials) to elicit adverse caregiving conditions (including maltreatment) toward rodent neonates. Our lab utilizes a version of this model wherein caregiving exposures occur outside the home cage during the first postnatal week. The aim of this study was to determine adolescent and adult phenotypic outcomes associated with this model, including assessment of depressive- and anxiety-like behaviors and performance in different cognitive domains. Exposure to adverse caregiving had no effect on adolescent behavioral performance whereas exposure significantly impaired adult behavioral performance. Further, adult behavioral assays revealed substantial differences between sexes. Overall, data demonstrate the ability of repeated exposure to brief bouts of maltreatment outside the home cage in infancy to impact the development of several behavioral domains later in life.
Collapse
Affiliation(s)
- Tiffany S. Doherty
- Department of Psychological and Brain Sciences, University of Delaware,
Newark DE 19716
| | | | | | - Tania L. Roth
- Department of Psychological and Brain Sciences, University of Delaware,
Newark DE 19716
| |
Collapse
|
38
|
Ianov L, Riva A, Kumar A, Foster TC. DNA Methylation of Synaptic Genes in the Prefrontal Cortex Is Associated with Aging and Age-Related Cognitive Impairment. Front Aging Neurosci 2017; 9:249. [PMID: 28824413 PMCID: PMC5539085 DOI: 10.3389/fnagi.2017.00249] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 07/14/2017] [Indexed: 01/17/2023] Open
Abstract
The current study investigates DNA methylation as a possible epigenetic regulator of transcription associated with aging and cognitive function. Young and aged male Fischer 344 rats were behaviorally characterized on a set shifting task, and whole genome bisulfite sequencing was employed to profile the DNA methylome of the medial prefrontal cortex (mPFC). DNA methylation was also compared to RNA expression in the mPFC from the same animals. Variability in methylation was mainly observed for CpG sites as opposed to CHG and CHH sites. Gene bodies, specifically introns, contain the highest levels of methylation. During aging, hypermethylation was observed for genes linked to synaptic function and GTPase activity. Furthermore, impaired cognitive flexibility during aging was associated with hypermethylation of genes linked to postsynaptic density, dendrites, the axon terminus, and Ca2+ channels. Finally, comparison with RNA expression confirmed that hypermethylation was correlated with decreased expression of synaptic genes. The results indicate that DNA methylation over the lifespan contributes to synaptic modification observed in brain aging and age-related cognitive impairment.
Collapse
Affiliation(s)
- Lara Ianov
- Department of Neuroscience, McKnight Brain Institute, University of Florida, GainesvilleFL, United States.,Genetics and Genomics Program, Genetics Institute, University of Florida, GainesvilleFL, United States
| | - Alberto Riva
- Bioinformatics Core, Interdisciplinary Center for Biotechnology Research, University of Florida, GainesvilleFL, United States
| | - Ashok Kumar
- Department of Neuroscience, McKnight Brain Institute, University of Florida, GainesvilleFL, United States
| | - Thomas C Foster
- Department of Neuroscience, McKnight Brain Institute, University of Florida, GainesvilleFL, United States.,Genetics and Genomics Program, Genetics Institute, University of Florida, GainesvilleFL, United States
| |
Collapse
|
39
|
Herbeck YE, Khantemirova AR, Antonov EV, Goncharova NI, Gulevich RG, Shepeleva DV, Trut LN. Expression of the DNA methyltransferase genes in silver foxes experimentally selected for domestication. RUSS J GENET+ 2017. [DOI: 10.1134/s1022795417040056] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
|
40
|
Epigenetic programming by stress and glucocorticoids along the human lifespan. Mol Psychiatry 2017; 22:640-646. [PMID: 28289275 DOI: 10.1038/mp.2017.35] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Revised: 01/08/2017] [Accepted: 01/17/2017] [Indexed: 12/19/2022]
Abstract
Psychosocial stress triggers a set of behavioral, neural, hormonal, and molecular responses that can be a driving force for survival when adaptive and time-limited, but may also contribute to a host of disease states if dysregulated or chronic. The beneficial or detrimental effects of stress are largely mediated by the hypothalamic-pituitary axis, a highly conserved neurohormonal cascade that culminates in systemic secretion of glucocorticoids. Glucocorticoids activate the glucocorticoid receptor, a ubiquitous nuclear receptor that not only causes widespread changes in transcriptional programs, but also induces lasting epigenetic modifications in many target tissues. While the epigenome remains sensitive to stressors throughout life, we propose two key principles that may govern the epigenetics of stress and glucocorticoids along the lifespan: first, the presence of distinct life periods, during which the epigenome shows heightened plasticity to stress exposure, such as in early development and at advanced age; and, second, the potential of stress-induced epigenetic changes to accumulate throughout life both in select chromatin regions and at the genome-wide level. These principles have important clinical and translational implications, and they show striking parallels with the existence of sensitive developmental periods and the cumulative impact of stressful experiences on the development of stress-related phenotypes. We hope that this conceptual mechanistic framework will stimulate fruitful research that aims at unraveling the molecular pathways through which our life stories sculpt genomic function to contribute to complex behavioral and somatic phenotypes.
Collapse
|
41
|
Makhathini KB, Abboussi O, Stein DJ, Mabandla MV, Daniels WM. Repetitive stress leads to impaired cognitive function that is associated with DNA hypomethylation, reduced BDNF and a dysregulated HPA axis. Int J Dev Neurosci 2017; 60:63-69. [DOI: 10.1016/j.ijdevneu.2017.04.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 03/13/2017] [Accepted: 04/11/2017] [Indexed: 11/28/2022] Open
Affiliation(s)
- Khayelihle B. Makhathini
- Department of Human PhysiologyCollege of Health Sciences, University of KwaZulu‐ NatalDurbanSouth Africa
| | - Oualid Abboussi
- Department of Human PhysiologyCollege of Health Sciences, University of KwaZulu‐ NatalDurbanSouth Africa
| | - Dan J. Stein
- Department of PsychiatryUniversity of Cape TownCape TownSouth Africa
| | - Musa V. Mabandla
- Department of Human PhysiologyCollege of Health Sciences, University of KwaZulu‐ NatalDurbanSouth Africa
| | | |
Collapse
|
42
|
Guo XX, He QZ, Li W, Long DX, Pan XY, Chen C, Zeng HC. Brain-Derived Neurotrophic Factor Mediated Perfluorooctane Sulfonate Induced-Neurotoxicity via Epigenetics Regulation in SK-N-SH Cells. Int J Mol Sci 2017; 18:ijms18040893. [PMID: 28441774 PMCID: PMC5412472 DOI: 10.3390/ijms18040893] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 04/17/2017] [Accepted: 04/19/2017] [Indexed: 12/12/2022] Open
Abstract
Perfluorooctane sulfonate (PFOS), a new kind of persistent organic pollutant, is widely distributed in the environment and exists in various organisms, where it is also a neurotoxic compound. However, the potential mechanism of its neurotoxicity is still unclear. To examine the role of epigenetics in the neurotoxicity induced by PFOS, SK-N-SH cells were treated with different concentrations of PFOS or control medium (0.1% DMSO) for 48 h. The mRNA levels of DNA methyltransferases (DNMTs) and Brain-derived neurotrophic factor (BDNF), microRNA-16, microRNA-22, and microRNA-30a-5p were detected by Quantitative PCR (QPCR). Enzyme Linked Immunosorbent Assay (ELISA) was used to measure the protein levels of BDNF, and a western blot was applied to analyze the protein levels of DNMTs. Bisulfite sequencing PCR (BSP) was used to detect the methylation status of the BDNF promoter I and IV. Results of MTT assays indicated that treatment with PFOS could lead to a significant decrease of cell viability, and the treated cells became shrunk. In addition, PFOS exposure decreased the expression of BDNF at mRNA and protein levels, increased the expression of microRNA-16, microRNA-22, microRNA-30a-5p, and decreased the expression of DNMT1 at mRNA and protein levels, but increased the expression of DNMT3b at mRNA and protein levels. Our results also demonstrate that PFOS exposure changes the methylation status of BDNF promoter I and IV. The findings of the present study suggest that methylation regulation of BDNF gene promoter and increases of BDNF-related-microRNA might underlie the mechanisms of PFOS-induced neurotoxicity.
Collapse
Affiliation(s)
- Xin-Xin Guo
- Department of Preventive Medicine, School of Public Health, University of South China, Hengyang 421001, China.
| | - Qing-Zhi He
- School of Pharmacy and Biology, University of South China, Hengyang 421001, China.
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang 421001, China.
| | - Wu Li
- Department of Preventive Medicine, School of Public Health, University of South China, Hengyang 421001, China.
| | - Ding-Xin Long
- Department of Preventive Medicine, School of Public Health, University of South China, Hengyang 421001, China.
| | - Xiao-Yuan Pan
- Department of Preventive Medicine, School of Public Health, University of South China, Hengyang 421001, China.
| | - Cong Chen
- Department of Preventive Medicine, School of Public Health, University of South China, Hengyang 421001, China.
| | - Huai-Cai Zeng
- Department of Preventive Medicine, School of Public Health, University of South China, Hengyang 421001, China.
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang 421001, China.
| |
Collapse
|
43
|
Nishi M, Sasagawa T, Horii-Hayashi N. Effects of early life adverse experiences on the brain: implications from maternal separation. Nihon Yakurigaku Zasshi 2017; 149:72-75. [PMID: 28154300 DOI: 10.1254/fpj.149.72] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
44
|
Sasagawa T, Horii-Hayashi N, Okuda A, Hashimoto T, Azuma C, Nishi M. Long-term effects of maternal separation coupled with social isolation on reward seeking and changes in dopamine D1 receptor expression in the nucleus accumbens via DNA methylation in mice. Neurosci Lett 2017; 641:33-39. [DOI: 10.1016/j.neulet.2017.01.025] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 12/26/2016] [Accepted: 01/11/2017] [Indexed: 01/10/2023]
|
45
|
Zhu Y, Wang Y, Yao R, Hao T, Cao J, Huang H, Wang L, Wu Y. Enhanced neuroinflammation mediated by DNA methylation of the glucocorticoid receptor triggers cognitive dysfunction after sevoflurane anesthesia in adult rats subjected to maternal separation during the neonatal period. J Neuroinflammation 2017; 14:6. [PMID: 28086911 PMCID: PMC5234142 DOI: 10.1186/s12974-016-0782-5] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 12/20/2016] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Mounting evidence indicates that children who experience abuse and neglect are prone to chronic diseases and premature mortality later in life. One mechanistic hypothesis for this phenomenon is that early life adversity alters the expression or functioning of the glucocorticoid receptor (GR) throughout the course of life and thereby increases sensitivity to inflammatory stimulation. An exaggerated pro-inflammatory response is generally considered to be a key cause of postoperative cognitive dysfunction (POCD). The aim of this study was to examine the effects of early life adversity on cognitive function and neuroinflammation after sevoflurane anesthesia in adult rats and to determine whether such effects are associated with the epigenetic regulation of GR. METHODS Wistar rat pups were repeatedly subjected to infant maternal separation (early life stress) from postnatal days 2-21. In adulthood, their behavior and the signaling of hippocampal pro-inflammatory factors and nuclear factor-kappa B (NF-κB) after sevoflurane anesthesia were evaluated. We also examined the effects of maternal separation (MS) on the expression of GR and the DNA methylation status of the promoter region of exon 17 of GR and whether behavioral changes and neuroinflammation after anesthesia were reversible when the expression of GR was increased by altering DNA methylation. RESULTS MS induced cognitive decline after sevoflurane inhalation in the Morris water maze and context fear conditioning tests and enhanced the release of cytokines and the activation of astrocyte intracellular NF-κB signaling induced by sevoflurane in the hippocampus of adult rats. Blocking NF-κB signaling by pyrrolidine dithiocarbamate (PDTC) inhibited the release of cytokines. MS also reduced the expression of GR and upregulated the methylation levels of the promoter region of GR exon 17, and such effects were reversed by treatment with the histone deacetylase inhibitor trichostatin A (TSA) in adult rats. Moreover, TSA treatment in adult MS rats inhibited the overactivation of astrocyte intracellular NF-κB signaling and the release of cytokines and alleviated cognitive dysfunction after sevoflurane anesthesia. CONCLUSIONS Early life stress induces cognitive dysfunction after sevoflurane anesthesia, perhaps due to the aberrant methylation of the GR gene promoter, which reduces the expression of the GR gene and facilitates exaggerated inflammatory responses.
Collapse
Affiliation(s)
- Yangzi Zhu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, 209 Tongshan, Xuzhou, 221004, People's Republic of China.,Department of Anesthesiology, Xuzhou Central Hospital, 199 Jiefang South Road, Xuzhou, People's Republic of China
| | - Yu Wang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, 209 Tongshan, Xuzhou, 221004, People's Republic of China
| | - Rui Yao
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, 209 Tongshan, Xuzhou, 221004, People's Republic of China
| | - Ting Hao
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, 209 Tongshan, Xuzhou, 221004, People's Republic of China
| | - Junli Cao
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, 209 Tongshan, Xuzhou, 221004, People's Republic of China
| | - He Huang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, 209 Tongshan, Xuzhou, 221004, People's Republic of China
| | - Liwei Wang
- Department of Anesthesiology, Xuzhou Central Hospital, 199 Jiefang South Road, Xuzhou, People's Republic of China.
| | - Yuqing Wu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, 209 Tongshan, Xuzhou, 221004, People's Republic of China. .,Department of Anesthetic Pharmacology, Xuzhou Medical University, Xuzhou, People's Republic of China.
| |
Collapse
|
46
|
Majcher‐Maślanka I, Solarz A, Wędzony K, Chocyk A. The effects of early‐life stress on dopamine system function in adolescent female rats. Int J Dev Neurosci 2017; 57:24-33. [DOI: 10.1016/j.ijdevneu.2017.01.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 01/02/2017] [Accepted: 01/03/2017] [Indexed: 12/16/2022] Open
Affiliation(s)
- Iwona Majcher‐Maślanka
- Institute of Pharmacology, Polish Academy of SciencesLaboratory of Pharmacology and Brain Biostructure31‐343KrakówSmętna Street 12Poland
| | - Anna Solarz
- Institute of Pharmacology, Polish Academy of SciencesLaboratory of Pharmacology and Brain Biostructure31‐343KrakówSmętna Street 12Poland
| | - Krzysztof Wędzony
- Institute of Pharmacology, Polish Academy of SciencesLaboratory of Pharmacology and Brain Biostructure31‐343KrakówSmętna Street 12Poland
| | - Agnieszka Chocyk
- Institute of Pharmacology, Polish Academy of SciencesLaboratory of Pharmacology and Brain Biostructure31‐343KrakówSmętna Street 12Poland
| |
Collapse
|
47
|
McCoy CR, Rana S, Stringfellow SA, Day JJ, Wyss JM, Clinton SM, Kerman IA. Neonatal maternal separation stress elicits lasting DNA methylation changes in the hippocampus of stress-reactive Wistar Kyoto rats. Eur J Neurosci 2016; 44:2829-2845. [PMID: 27643783 DOI: 10.1111/ejn.13404] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 09/13/2016] [Accepted: 09/13/2016] [Indexed: 01/21/2023]
Abstract
Early-life stress (ELS) can alter neurodevelopment in variable ways, ranging from producing deleterious outcomes to stress resilience. While most ELS studies focus on its harmful effects, recent work by our laboratory and others shows that ELS elicits positive effects in certain individuals. We exposed Wistar Kyoto (WKY) rats, known for a stress reactive, anxiety/depression-like phenotype, to maternal separation (MS), a model of ELS. MS exposure elicited anxiolytic and antidepressant behavioral effects as well as improved cardiovascular function in adult WKY offspring. This study interrogates an epigenetic mechanism (DNA methylation) that may confer the adaptive effects of MS in WKY offspring. We quantified global genome methylation levels in limbic brain regions of adult WKYs exposed to daily 180-min MS or neonatal handling from postnatal day 1-14. MS exposure triggered dramatic DNA hypermethylation specifically in the hippocampus. Next-generation sequencing methylome profiling revealed reduced methylation at intragenic sites within two key nodes of insulin signaling pathways: the insulin receptor and one of its major downstream targets, mitogen-activated protein kinase kinase kinase 5 (Map3k5). We then tested the hypothesis that enhancing DNA methylation in WKY rats would elicit adaptive changes akin to the effects of MS. Dietary methyl donor supplementation improved WKY rats' anxiety/depression-like behaviors and also improved cardiovascular measures, similar to previous observations following MS. Overall, these data suggest a potential molecular mechanism that mediates a predicted adaptive response, whereby ELS induces DNA methylation changes in the brain that may contribute to successful stress coping and adaptive physiological changes in adulthood.
Collapse
Affiliation(s)
- Chelsea R McCoy
- School of Neuroscience, Virginia Tech University, 1981 Kraft Drive, 2012 ILSB, Blacksburg, VA, 24060, USA
| | - Samir Rana
- Department of Cell, Developmental and Integrative Biology, University of Alabama, Birmingham, AL, USA
| | | | - Jeremy J Day
- Department of Neurobiology, University of Alabama, Birmingham, AL, USA
| | - J Michael Wyss
- Department of Cell, Developmental and Integrative Biology, University of Alabama, Birmingham, AL, USA
| | - Sarah M Clinton
- School of Neuroscience, Virginia Tech University, 1981 Kraft Drive, 2012 ILSB, Blacksburg, VA, 24060, USA
| | - Ilan A Kerman
- School of Neuroscience, Virginia Tech University, 1981 Kraft Drive, 2012 ILSB, Blacksburg, VA, 24060, USA.,Department of Psychiatry and Behavioral Medicine, Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
| |
Collapse
|
48
|
Insight from animal models of environmentally driven epigenetic changes in the developing and adult brain. Dev Psychopathol 2016; 28:1229-1243. [PMID: 27687803 DOI: 10.1017/s095457941600081x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The efforts of many neuroscientists are directed toward understanding the appreciable plasticity of the brain and behavior. In recent years, epigenetics has become a core of this focus as a prime mechanistic candidate for behavioral modifications. Animal models have been instrumental in advancing our understanding of environmentally driven changes to the epigenome in the developing and adult brain. This review focuses mainly on such discoveries driven by adverse environments along with their associated behavioral outcomes. While much of the evidence discussed focuses on epigenetics within the central nervous system, several peripheral studies in humans who have experienced significant adversity are also highlighted. As we continue to unravel the link between epigenetics and phenotype, discerning the complexity and specificity of epigenetic changes induced by environments is an important step toward understanding optimal development and how to prevent or ameliorate behavioral deficits bred by disruptive environments.
Collapse
|
49
|
Gondré-Lewis MC, Darius PJ, Wang H, Allard JS. Stereological analyses of reward system nuclei in maternally deprived/separated alcohol drinking rats. J Chem Neuroanat 2016; 76:122-132. [PMID: 26939765 DOI: 10.1016/j.jchemneu.2016.02.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Revised: 01/19/2016] [Accepted: 02/26/2016] [Indexed: 12/15/2022]
Abstract
The experience of early life stress can trigger complex neurochemical cascades that influence emotional and addictive behaviors later in life in both adolescents and adults. Recent evidence suggests that excessive alcohol drinking and drug-seeking behavior, in general, are co-morbid with depressive-like behavior. Both behaviors are reported in humans exposed to early life adversity, and are prominent features recapitulated in animal models of early life stress (ELS) exposure. Currently, little is known about whether or how ELS modulates reward system nuclei. In this study we use operant conditioning of rats to show that the maternal separation stress (MS) model of ELS consumes up to 3-fold greater quantities of 10% vol/vol EtOH in 1-h, consistently over a 3-week period. This was correlated with a significant 22% reduction in the number of dopaminergic-like neurons in the VTA of naïve MS rats, similar to genetically alcohol-preferring (P) rats which show a 35% reduction in tyrosine hydroxylase (TH)-positive dopaminergic neurons in the VTA. MS rats had a significantly higher 2-fold immobility time in the forced swim test (FST) and reduced sucrose drinking compared to controls, indicative of depressive-like symptomology and anhedonia. Consistent with this finding, stereological analysis revealed that amygdala neurons were 25% greater in number at P70 following MS exposure. Our previous examination of the dentate gyrus of hippocampus, a region involved in encoding emotional memory, revealed fewer dentate gyrus neurons after MS, but we now report this reduction in neurons occurs without effect on the number of astrocytes or length of astrocytic fibers. These data indicate that MS animals exhibit neuroanatomical changes in reward centers similar to those reported for high alcohol drinking rats, but aspects of astrocyte morphometry remained unchanged. These data are of high relevance to understand the breadth of neuronal pathology that ensues in reward loci following ELS.
Collapse
Affiliation(s)
- Marjorie C Gondré-Lewis
- Department of Anatomy, Howard University College of Medicine, Washington, DC 20059, United States; Department of Psychiatry and Behavioral Sciences, Howard University College of Medicine, Washington, DC 20059, United States.
| | - Philippe J Darius
- Department of Anatomy, Howard University College of Medicine, Washington, DC 20059, United States; Department of Psychiatry and Behavioral Sciences, Howard University College of Medicine, Washington, DC 20059, United States
| | - Hong Wang
- Department of Anatomy, Howard University College of Medicine, Washington, DC 20059, United States
| | - Joanne S Allard
- Department of Physiology and Biophysics, Howard University College of Medicine, Washington, DC 20059, United States
| |
Collapse
|
50
|
Hypermethylation of Hippocampal Synaptic Plasticity-Related genes is Involved in Neonatal Sevoflurane Exposure-Induced Cognitive Impairments in Rats. Neurotox Res 2015; 29:243-55. [PMID: 26678494 DOI: 10.1007/s12640-015-9585-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2015] [Revised: 11/24/2015] [Accepted: 12/06/2015] [Indexed: 10/24/2022]
Abstract
General anesthetics given to immature rodents cause delayed neurobehavioral abnormalities via incompletely understood mechanisms. DNA methylation, one of the epigenetic modifications, is essential for the modulation of hippocampal synaptic plasticity through regulating the related genes. Therefore, we investigated whether abnormalities in the hippocampal DNA methylation of synaptic plasticity-related genes are involved in neonatal sevoflurane exposure-induced cognitive impairments in rats. Male Sprague-Dawley rats were exposed to 3 % sevoflurane or 30 % oxygen/air for 2 h daily from postnatal day 7 (P7) to P9 and were treated with DNA methyltransferases (DNMTs) inhibitor 5-aza-2-deoxycytidine (5-AZA) or vehicle 1 h before the first sevoflurane exposure on P7. The rats were euthanized 1, 6, 24 h, and 30 days after the last sevoflurane exposure, and the brain tissues were harvested for biochemical analysis. Cognitive functions were evaluated by the open field, fear conditioning, and Morris water maze (MWM) tests on P39, P41-43, and P50-57, respectively. In the present study, repeated neonatal sevoflurane exposure resulted in hippocampus-dependent cognitive impairments as assessed by fear conditioning and MWM tests. The cognitive impairments were associated with the increased DNMTs and hypermethylation of brain-derived neurotrophic factor (BDNF) and Reelin genes, and subsequent down-regulation of BDNF and Reelin genes, which finally led to the decrease of dendritic spines in the hippocampal pyramidal neurons in adolescent rats. Notably, pretreatment with 5-AZA reversed these sevoflurane-induced abnormalities. In conclusion, our results suggest that hypermethylation of hippocampal BDNF and Reelin is involved in neonatal sevoflurane exposure-induced cognitive impairments.
Collapse
|