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Orrù A, Caffino L, Moro F, Cassina C, Giannotti G, Di Clemente A, Fumagalli F, Cervo L. Contingent and non-contingent recreational-like exposure to ethanol alters BDNF expression and signaling in the cortico-accumbal network differently. Psychopharmacology (Berl) 2016; 233:3149-60. [PMID: 27370019 DOI: 10.1007/s00213-016-4358-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 06/09/2016] [Indexed: 01/03/2023]
Abstract
RATIONALE Although brain-derived neurotrophic factor (BDNF) is part of a homeostatic pathway involved in the development of alcohol dependence, it is not clear whether this is also true after recreational ethanol consumption. OBJECTIVES We examined BDNF expression and signaling in the cortico-striatal network immediately and 24 h after either a single intravenous (i.v.) ethanol operant self-administration session or the last of 14 sessions. METHODS To compare contingent and non-contingent ethanol exposure, we incorporated the "yoked control-operant paradigm" in which rats actively taking ethanol (S-Et) were paired with two yoked controls receiving passive infusions of ethanol (Y-Et) or saline. RESULTS A single ethanol exposure transiently reduced BDNF mRNA levels in the medial prefrontal cortex (mPFC) of Y-Et. Immediately after the last of 14 sessions, mRNA and mature BDNF protein levels (mBDNF) were reduced in the mPFC in both S-Et and Y-Et while mBDNF expression was raised in the nucleus accumbens (NAc), suggesting enhanced anterograde transport from the mPFC. Conversely, 24 h later mBDNF expression and signaling were raised in the mPFC and NAc of S-Et rats but reduced in the NAc of Y-Et rats, with concomitant reduction of downstream signaling pathways. CONCLUSIONS Our findings indicate that recreational-like i.v. doses of ethanol promote early changes in neurotrophin expression, depending on the length and modality of administration, the brain region investigated, and the presence of the drug. A rapid intervention targeting the BDNF system might be useful to prevent escalation to alcohol abuse.
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Affiliation(s)
- Alessandro Orrù
- Experimental Psychopharmacology, Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche 'Mario Negri', Via Giuseppe La Masa 19, 20156, Milan, Italy.
- Institute of Translational Pharmacology (C.N.R.), Parco Scientifico e Tecnologico della Sardegna, Polaris - Edificio 5 - Località, Piscinamanna, 09010, Pula, Cagliari, Italy.
| | - Lucia Caffino
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Balzaretti 9, 20133, Milan, Italy
| | - Federico Moro
- Experimental Psychopharmacology, Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche 'Mario Negri', Via Giuseppe La Masa 19, 20156, Milan, Italy
| | - Chiara Cassina
- Experimental Psychopharmacology, Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche 'Mario Negri', Via Giuseppe La Masa 19, 20156, Milan, Italy
| | - Giuseppe Giannotti
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Balzaretti 9, 20133, Milan, Italy
| | - Angelo Di Clemente
- Experimental Psychopharmacology, Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche 'Mario Negri', Via Giuseppe La Masa 19, 20156, Milan, Italy
| | - Fabio Fumagalli
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Balzaretti 9, 20133, Milan, Italy
| | - Luigi Cervo
- Experimental Psychopharmacology, Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche 'Mario Negri', Via Giuseppe La Masa 19, 20156, Milan, Italy.
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Abstract
The main characteristic of alcohol use disorder is the consumption of large quantities of alcohol despite the negative consequences. The transition from the moderate use of alcohol to excessive, uncontrolled alcohol consumption results from neuroadaptations that cause aberrant motivational learning and memory processes. Here, we examine studies that have combined molecular and behavioural approaches in rodents to elucidate the molecular mechanisms that keep the social intake of alcohol in check, which we term 'stop pathways', and the neuroadaptations that underlie the transition from moderate to uncontrolled, excessive alcohol intake, which we term 'go pathways'. We also discuss post-transcriptional, genetic and epigenetic alterations that underlie both types of pathways.
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Affiliation(s)
- Dorit Ron
- Corresponding author: Dorit Ron, 675 Nelson Rising Lane, BOX 0663, San Francisco, CA 94143-0663,
| | - Segev Barak
- Department of Neurology, University of California, San Francisco, San Francisco, CA 94143, USA
- School of Psychological Sciences and Sagol School of Neuroscience, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel
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Wang J, Zhao J, Liu Z, Guo F, Wang Y, Wang X, Zhang R, Vreugdenhil M, Lu C. Acute Ethanol Inhibition of γ Oscillations Is Mediated by Akt and GSK3β. Front Cell Neurosci 2016; 10:189. [PMID: 27582689 PMCID: PMC4987361 DOI: 10.3389/fncel.2016.00189] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Accepted: 07/19/2016] [Indexed: 01/23/2023] Open
Abstract
Hippocampal network oscillations at gamma band frequency (γ, 30-80 Hz) are closely associated with higher brain functions such as learning and memory. Acute ethanol exposure at intoxicating concentrations (≥50 mM) impairs cognitive function. This study aimed to determine the effects and the mechanisms of acute ethanol exposure on γ oscillations in an in vitro model. Ethanol (25-100 mM) suppressed kainate-induced γ oscillations in CA3 area of the rat hippocampal slices, in a concentration-dependent, reversible manner. The ethanol-induced suppression was reduced by the D1R antagonist SCH23390 or the PKA inhibitor H89, was prevented by the Akt inhibitor triciribine or the GSk3β inhibitor SB415286, was enhanced by the NMDA receptor antagonist D-AP5, but was not affected by the MAPK inhibitor U0126 or PI3K inhibitor wortmanin. Our results indicate that the intracellular kinases Akt and GSk3β play a critical role in the ethanol-induced suppression of γ oscillations and reveal new cellular pathways involved in the ethanol-induced cognitive impairment.
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Affiliation(s)
- JianGang Wang
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical UniversityXinxiang, China; Department of Pathophysiology, Xinxiang Medical UniversityXinxiang, China
| | - JingXi Zhao
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical UniversityXinxiang, China; Psychiatric Hospital of Henan ProvinceXinxiang, China
| | - ZhiHua Liu
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical UniversityXinxiang, China; Psychiatric Hospital of Henan ProvinceXinxiang, China
| | - FangLi Guo
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical UniversityXinxiang, China; Department of Neurobiology and Physiology, Xinxiang Medical UniversityXinxiang, China
| | - Yali Wang
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical UniversityXinxiang, China; Department of Neurobiology and Physiology, Xinxiang Medical UniversityXinxiang, China
| | - Xiaofang Wang
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical University Xinxiang, China
| | - RuiLing Zhang
- Psychiatric Hospital of Henan Province Xinxiang, China
| | - Martin Vreugdenhil
- Department of Psychology, Xinxiang Medical UniversityHenan, China; Department of Health Sciences, Birmingham City UniversityBirmingham, UK
| | - Chengbiao Lu
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical UniversityXinxiang, China; Psychiatric Hospital of Henan ProvinceXinxiang, China
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Alcohol-induced suppression of KDM6B dysregulates the mineralization potential in dental pulp stem cells. Stem Cell Res 2016; 17:111-21. [PMID: 27286573 DOI: 10.1016/j.scr.2016.05.021] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 05/25/2016] [Accepted: 05/25/2016] [Indexed: 12/22/2022] Open
Abstract
Epigenetic changes, such as alteration of DNA methylation patterns, have been proposed as a molecular mechanism underlying the effect of alcohol on the maintenance of adult stem cells. We have performed genome-wide gene expression microarray and DNA methylome analysis to identify molecular alterations via DNA methylation changes associated with exposure of human dental pulp stem cells (DPSCs) to ethanol (EtOH). By combined analysis of the gene expression and DNA methylation, we have found a significant number of genes that are potentially regulated by EtOH-induced DNA methylation. As a focused approach, we have also performed a pathway-focused RT-PCR array analysis to examine potential molecular effects of EtOH on genes involved in epigenetic chromatin modification enzymes, fibroblastic markers, and stress and toxicity pathways in DPSCs. We have identified and verified that lysine specific demethylase 6B (KDM6B) was significantly dysregulated in DPSCs upon EtOH exposure. EtOH treatment during odontogenic/osteogenic differentiation of DPSCs suppressed the induction of KDM6B with alterations in the expression of differentiation markers. Knockdown of KDM6B resulted in a marked decrease in mineralization from implanted DPSCs in vivo. Furthermore, an ectopic expression of KDM6B in EtOH-treated DPSCs restored the expression of differentiation-related genes. Our study has demonstrated that EtOH-induced inhibition of KDM6B plays a role in the dysregulation of odontogenic/osteogenic differentiation in the DPSC model. This suggests a potential molecular mechanism for cellular insults of heavy alcohol consumption that can lead to decreased mineral deposition potentially associated with abnormalities in dental development and also osteopenia/osteoporosis, hallmark features of fetal alcohol spectrum disorders.
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Lhullier AC, Moreira FP, da Silva RA, Marques MB, Bittencourt G, Pinheiro RT, Souza LDM, Portela LV, Lara DR, Jansen K, Wiener CD, Oses JP. Increased serum neurotrophin levels related to alcohol use disorder in a young population sample. Alcohol Clin Exp Res 2016; 39:30-3. [PMID: 25623403 DOI: 10.1111/acer.12592] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 10/01/2014] [Indexed: 02/02/2023]
Abstract
BACKGROUND The diagnosis of alcohol use disorder is based on clinical signs and on the measurement of biological markers. However, these markers are neither sufficiently sensitive, nor specific enough, for determining the effects of alcohol abuse on the central nervous system. Serum neurotrophins are important regulators of neural survival, development, function, and plasticity and have been found to be reduced in alcohol use disorder. The aim of this study was to investigate the alterations in serum neurotrophin levels (brain-derived neurotrophic factor [BDNF], glial-derived neurotrophic factor [GDNF], and nerve growth factor [NGF]) in alcohol use disorder in a young population, and thus possibly representing the early stages of the illness. METHODS This is a cross-sectional study, nested in a population-based study of people aged 18 to 35, involving 795 participants. The participants responded to the CAGE questionnaire, and a CAGE score of ≥2 was considered to be a positive screen for the abuse/dependence or moderate to severe alcohol use disorder. Serum BDNF, GDNF, and NGF levels were measured by ELISA. RESULTS In the CAGE ≥ 2 group, GDNF (p ≤ 0.001) and NGF (p ≤ 0.001) serum levels were significantly increased, and the BDNF elevation was near a statistical significance (p = 0.068) when compared to the CAGE < 2 group. A significantly positive correlation was observed only in the CAGE ≥ 2 group for BDNF/GDNF (r = 0.37, p < 0.001) and GDNF/NGF (r = 0.84, p < 0.001) levels. The correlation between the NGF and BDNF levels was significantly positive in both groups (r = 0.28, p < 0.001 for the CAGE < 2 group, and r = 0.30, p = 0.008 for the CAGE ≥ 2 group). CONCLUSIONS These results suggest that elevated neurotrophins are candidate markers for the early stages of alcohol misuse.
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Affiliation(s)
- Alfredo C Lhullier
- Escola de Psicologia, Centro de Ciências da Vida e da Saúde, Universidade Católica de Pelotas, Pelotas, Brazil
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Xu YH, Wang LL, Shi L, Lei JP, Miao Q, Liu TQ, Hao W, Lu L, Zhang RL. The association of HTR3A mRNA expression and craving in Han Chinese alcohol-dependent patients: a preliminary study. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 2016; 42:316-24. [PMID: 27144979 DOI: 10.3109/00952990.2016.1160098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Ya-Hui Xu
- Department of Addiction, Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan Province, China
| | - Lin-Lin Wang
- Department of Psychology, Ninth People Hospital of Zhengzhou, Zhengzhou, Henan Province, China
| | - Le Shi
- Peking University Sixth Hospital/Institute of Mental Health and Key Laboratory of Mental Health and National Institute on Drug Dependence, Peking University, Beijing, China
| | - Jin-Ping Lei
- People Hospital of Cangzhou, Cangzhou, Hebei Province, China
| | - Qin Miao
- Department of Addiction, Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan Province, China
| | - Tie-Qiao Liu
- Mental Health Institute, Second Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Wei Hao
- Mental Health Institute, Second Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Lin Lu
- Peking University Sixth Hospital/Institute of Mental Health and Key Laboratory of Mental Health and National Institute on Drug Dependence, Peking University, Beijing, China
| | - Rui-Ling Zhang
- Department of Addiction, Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan Province, China
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57
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Beneficial effects of chlorogenic acid on alcohol-induced damage in PC12 cells. Biomed Pharmacother 2016; 79:254-62. [DOI: 10.1016/j.biopha.2016.02.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 02/25/2016] [Accepted: 02/27/2016] [Indexed: 11/18/2022] Open
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Bell RL, Hauser S, Rodd ZA, Liang T, Sari Y, McClintick J, Rahman S, Engleman EA. A Genetic Animal Model of Alcoholism for Screening Medications to Treat Addiction. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2016; 126:179-261. [PMID: 27055615 PMCID: PMC4851471 DOI: 10.1016/bs.irn.2016.02.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The purpose of this review is to present up-to-date pharmacological, genetic, and behavioral findings from the alcohol-preferring P rat and summarize similar past work. Behaviorally, the focus will be on how the P rat meets criteria put forth for a valid animal model of alcoholism with a highlight on its use as an animal model of polysubstance abuse, including alcohol, nicotine, and psychostimulants. Pharmacologically and genetically, the focus will be on the neurotransmitter and neuropeptide systems that have received the most attention: cholinergic, dopaminergic, GABAergic, glutamatergic, serotonergic, noradrenergic, corticotrophin releasing hormone, opioid, and neuropeptide Y. Herein, we sought to place the P rat's behavioral and neurochemical phenotypes, and to some extent its genotype, in the context of the clinical literature. After reviewing the findings thus far, this chapter discusses future directions for expanding the use of this genetic animal model of alcoholism to identify molecular targets for treating drug addiction in general.
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Affiliation(s)
- R L Bell
- Institute of Psychiatric Research, Indiana University School of Medicine, Indianapolis, IN, United States.
| | - S Hauser
- Institute of Psychiatric Research, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Z A Rodd
- Institute of Psychiatric Research, Indiana University School of Medicine, Indianapolis, IN, United States
| | - T Liang
- Indiana University School of Medicine, Indianapolis, IN, United States
| | - Y Sari
- University of Toledo, Toledo, OH, United States
| | - J McClintick
- Center for Medical Genomics, Indiana University School of Medicine, Indianapolis, IN, United States
| | - S Rahman
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD, United States
| | - E A Engleman
- Institute of Psychiatric Research, Indiana University School of Medicine, Indianapolis, IN, United States
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59
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Pandey SC. A Critical Role of Brain-Derived Neurotrophic Factor in Alcohol Consumption. Biol Psychiatry 2016; 79:427-9. [PMID: 26893193 PMCID: PMC4945157 DOI: 10.1016/j.biopsych.2015.12.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 12/22/2015] [Accepted: 12/25/2015] [Indexed: 01/24/2023]
Affiliation(s)
- Subhash C. Pandey
- Center for Alcohol Research in Epigenetics, Department of
Psychiatry, University of Illinois at Chicago, Chicago IL 60612,Anatomy and Cell Biology, University of Illinois at Chicago,
Chicago IL 60612,Jesse Brown Veterans Affairs Medical Center Chicago, IL 60612
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60
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Zhang XY, Tan YL, Chen DC, Tan SP, Yang FD, Zunta-Soares GB, Soares JC. Effects of cigarette smoking and alcohol use on neurocognition and BDNF levels in a Chinese population. Psychopharmacology (Berl) 2016; 233:435-45. [PMID: 26518023 DOI: 10.1007/s00213-015-4124-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2015] [Accepted: 10/13/2015] [Indexed: 12/29/2022]
Abstract
OBJECTIVE Few studies have examined the potential interactive effect of both smoking and drinking on cognition. Brain-derived neurotrophic factor (BDNF) plays a critical role in cognition. This is the first study to examine the neurocognitive consequences of cigarette smoking combined with chronic alcohol consumption and their relationship to serum BDNF levels in a Chinese Han population. MATERIALS AND METHODS We recruited 191 healthy male subjects, including 47 isolated smokers, 31 isolated chronic alcohol users, 58 combined smokers and chronic alcohol users, and 55 non-smokers and non-alcohol users. We then compared the repeatable battery for the assessment of neuropsychological status (RBANS) scores and serum BDNF levels in these four groups. RESULTS When compared to the non-smoking + non-alcohol-using group, the smoking group performed worse on immediate memory, attention, language, and RBANS total score. There were no significant differences in the RBANS scores between the alcohol-using group and non-smoking + non-alcohol-using group, or between the smoking group and smoking + alcohol-using group. We did not find an association between BDNF and smoking or drinking status or between BDNF and cognitive performance. In the smoking group, there was a significant correlation between BDNF and carbon monoxide concentration, and between BDNF and the Fagerstrom Test for Nicotine Dependence (FTND) total score. CONCLUSIONS Our results suggest that smoking is associated with cognitive decline, but not with BDNF levels in a normal population. However, smoking severity is positively associated with BDNF levels. Concomitant alcohol use does not worsen the cognitive decline caused by smoking.
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Affiliation(s)
- Xiang Yang Zhang
- Beijing HuiLongGuan Hospital, Peking University, Beijing, China.
- Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, USA.
- UT Center of Excellence on Mood Disorders (UTCEMD), Biomedical and Behavioral Sciences Building, 1941 East Road, Houston, TX, 77054, USA.
| | - Yun-Long Tan
- Beijing HuiLongGuan Hospital, Peking University, Beijing, China
| | - Da-Chun Chen
- Beijing HuiLongGuan Hospital, Peking University, Beijing, China
| | - Shu-Ping Tan
- Beijing HuiLongGuan Hospital, Peking University, Beijing, China
| | - Fu-De Yang
- Beijing HuiLongGuan Hospital, Peking University, Beijing, China
| | - Giovana B Zunta-Soares
- Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Jair C Soares
- Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, USA
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Anji A, Kumari M. Guardian of Genetic Messenger-RNA-Binding Proteins. Biomolecules 2016; 6:4. [PMID: 26751491 PMCID: PMC4808798 DOI: 10.3390/biom6010004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 12/02/2015] [Accepted: 12/04/2015] [Indexed: 12/18/2022] Open
Abstract
RNA in cells is always associated with RNA-binding proteins that regulate all aspects of RNA metabolism including RNA splicing, export from the nucleus, RNA localization, mRNA turn-over as well as translation. Given their diverse functions, cells express a variety of RNA-binding proteins, which play important roles in the pathologies of a number of diseases. In this review we focus on the effect of alcohol on different RNA-binding proteins and their possible contribution to alcohol-related disorders, and discuss the role of these proteins in the development of neurological diseases and cancer. We further discuss the conventional methods and newer techniques that are employed to identify RNA-binding proteins.
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Affiliation(s)
- Antje Anji
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA.
| | - Meena Kumari
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA.
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Mons N, Beracochea D. Behavioral Neuroadaptation to Alcohol: From Glucocorticoids to Histone Acetylation. Front Psychiatry 2016; 7:165. [PMID: 27766083 PMCID: PMC5052254 DOI: 10.3389/fpsyt.2016.00165] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 09/21/2016] [Indexed: 01/21/2023] Open
Abstract
A prime mechanism that contributes to the development and maintenance of alcoholism is the dysregulation of the hypothalamic-pituitary-adrenal axis activity and the release of glucocorticoids (cortisol in humans and primates, corticosterone in rodents) from the adrenal glands. In the brain, sustained, local elevation of glucocorticoid concentration even long after cessation of chronic alcohol consumption compromises functional integrity of a circuit, including the prefrontal cortex (PFC), the hippocampus (HPC), and the amygdala (AMG). These structures are implicated in learning and memory processes as well as in orchestrating neuroadaptive responses to stress and anxiety responses. Thus, potentiation of anxiety-related neuroadaptation by alcohol is characterized by an abnormally AMG hyperactivity coupled with a hypofunction of the PFC and the HPC. This review describes research on molecular and epigenetic mechanisms by which alcohol causes distinct region-specific adaptive changes in gene expression patterns and ultimately leads to a variety of cognitive and behavioral impairments on prefrontal- and hippocampal-based tasks. Alcohol-induced neuroadaptations involve the dysregulation of numerous signaling cascades, leading to long-term changes in transcriptional profiles of genes, through the actions of transcription factors such as [cAMP response element-binding protein (CREB)] and chromatin remodeling due to posttranslational modifications of histone proteins. We describe the role of prefrontal-HPC-AMG circuit in mediating the effects of acute and chronic alcohol on learning and memory, and region-specific molecular and epigenetic mechanisms involved in this process. This review first discusses the importance of brain region-specific dysregulation of glucocorticoid concentration in the development of alcohol dependence and describes how persistently increased glucocorticoid levels in PFC may be involved in mediating working memory impairments and neuroadaptive changes during withdrawal from chronic alcohol intake. It then highlights the role of cAMP-PKA-CREB signaling cascade and histone acetylation within the PFC and limbic structures in alcohol-induced anxiety and behavioral impairments, and how an understanding of functional alterations of these pathways might lead to better treatments for neuropsychiatric disorders.
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Affiliation(s)
- Nicole Mons
- CNRS UMR 5287, Institut des Neurosciences cognitives et intégratives d'Aquitaine, Nouvelle Université de Bordeaux , Pessac , France
| | - Daniel Beracochea
- CNRS UMR 5287, Institut des Neurosciences cognitives et intégratives d'Aquitaine, Nouvelle Université de Bordeaux , Pessac , France
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Sun WL, Quizon PM, Zhu J. Molecular Mechanism: ERK Signaling, Drug Addiction, and Behavioral Effects. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 137:1-40. [PMID: 26809997 DOI: 10.1016/bs.pmbts.2015.10.017] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Addiction to psychostimulants has been considered as a chronic psychiatric disorder characterized by craving and compulsive drug seeking and use. Over the past two decades, accumulating evidence has demonstrated that repeated drug exposure causes long-lasting neurochemical and cellular changes that result in enduring neuroadaptation in brain circuitry and underlie compulsive drug consumption and relapse. Through intercellular signaling cascades, drugs of abuse induce remodeling in the rewarding circuitry that contributes to the neuroplasticity of learning and memory associated with addiction. Here, we review the role of the extracellular signal-regulated kinase (ERK), a member of the mitogen-activated protein kinase, and its related intracellular signaling pathways in drug-induced neuroadaptive changes that are associated with drug-mediated psychomotor activity, rewarding properties and relapse of drug seeking behaviors. We also discuss the neurobiological and behavioral effects of pharmacological and genetic interferences with ERK-associated molecular cascades in response to abused substances. Understanding the dynamic modulation of ERK signaling in response to drugs may provide novel molecular targets for therapeutic strategies to drug addiction.
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Affiliation(s)
- Wei-Lun Sun
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, South Carolina, USA
| | - Pamela M Quizon
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, South Carolina, USA
| | - Jun Zhu
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, South Carolina, USA.
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Rashid MA, Kim HY. N-Docosahexaenoylethanolamine ameliorates ethanol-induced impairment of neural stem cell neurogenic differentiation. Neuropharmacology 2015; 102:174-85. [PMID: 26586023 DOI: 10.1016/j.neuropharm.2015.11.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 10/08/2015] [Accepted: 11/06/2015] [Indexed: 11/16/2022]
Abstract
Previous studies demonstrated that prenatal exposure to ethanol interferes with embryonic and fetal development, and causes abnormal neurodevelopment. Docosahexaenoic acid (DHA), an omega-3 polyunsaturated fatty acid highly enriched in the brain, was shown to be essential for proper brain development and function. Recently, we found that N-docosahexenoyethanolamine (synaptamide), an endogenous metabolite of DHA, is a potent PKA-dependent neurogenic factor for neural stem cell (NSC) differentiation. In this study, we demonstrate that ethanol at pharmacologically relevant concentrations downregulates cAMP signaling in NSC and impairs neurogenic differentiation. In contrast, synaptamide reverses ethanol-impaired NSC neurogenic differentiation through counter-acting on the cAMP production system. NSC exposure to ethanol (25-50 mM) for 4 days dose-dependently decreased the number of Tuj-1 positive neurons and PKA/CREB phosphorylation with a concomitant reduction of cellular cAMP. Ethanol-induced cAMP reduction was accompanied by the inhibition of G-protein activation and expression of adenylyl cyclase (AC) 7 and AC8, as well as PDE4 upregulation. In contrast to ethanol, synaptamide increased cAMP production, GTPγS binding, and expression of AC7 and AC8 isoforms in a cAMP-dependent manner, offsetting the ethanol-induced impairment in neurogenic differentiation. These results indicate that synaptamide can reduce ethanol-induced impairment of neuronal differentiation by counter-affecting shared targets in G-protein coupled receptor (GPCR)/cAMP signaling. The synaptamide-mediated mechanism observed in this study may offer a possible avenue for ameliorating the adverse impact of fetal alcohol exposure on neurodevelopment.
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Affiliation(s)
- Mohammad Abdur Rashid
- Laboratory of Molecular Signaling, DICBR, NIAAA, NIH, 5625 Fishers Lane, Bethesda, MD 20892-9410, USA
| | - Hee-Yong Kim
- Laboratory of Molecular Signaling, DICBR, NIAAA, NIH, 5625 Fishers Lane, Bethesda, MD 20892-9410, USA.
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Rahman S, Engleman EA, Bell RL. Recent Advances in Nicotinic Receptor Signaling in Alcohol Abuse and Alcoholism. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 137:183-201. [PMID: 26810002 PMCID: PMC4754113 DOI: 10.1016/bs.pmbts.2015.10.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Alcohol is the most commonly abused legal substance and alcoholism is a serious public health problem. It is a leading cause of preventable death in the world. The cellular and molecular mechanisms of alcohol reward and addiction are still not well understood. Emerging evidence indicates that unlike other drugs of abuse, such as nicotine, cocaine, or opioids, alcohol targets numerous channel proteins, receptor molecules, and signaling pathways in the brain. Previously, research has identified brain nicotinic acetylcholine receptors (nAChRs), a heterogeneous family of pentameric ligand-gated cation channels expressed in the mammalian brain, as critical molecular targets for alcohol abuse and dependence. Genetic variations encoding nAChR subunits have been shown to increase the vulnerability to develop alcohol dependence. Here, we review recent insights into the rewarding effects of alcohol, as they pertain to different nAChR subtypes, associated signaling molecules, and pathways that contribute to the molecular mechanisms of alcoholism and/or comorbid brain disorders. Understanding these cellular changes and molecular underpinnings may be useful for the advancement of brain nicotinic-cholinergic mechanisms, and will lead to a better translational and therapeutic outcome for alcoholism and/or comorbid conditions.
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Affiliation(s)
- Shafiqur Rahman
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, South Dakota, USA.
| | - Eric A Engleman
- Department of Psychiatry, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Richard L Bell
- Department of Psychiatry, Indiana University School of Medicine, Indianapolis, Indiana, USA
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Effects of acute ethanol exposure on class I HDACs family enzymes in wild-type and BDNF(+/-) mice. Drug Alcohol Depend 2015; 155:68-75. [PMID: 26361715 DOI: 10.1016/j.drugalcdep.2015.08.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 07/21/2015] [Accepted: 08/17/2015] [Indexed: 11/21/2022]
Abstract
BACKGROUND Alterations of brain-derived neurotrophic factor (BDNF) have been associated with the development of addiction to different drugs of abuse, including ethanol (EtOH). EtOH exposure activates the BDNF-signaling cascade in dorsal striatum, which in turn affects further EtOH intake. Different alcohol exposures have been widely demonstrated to modulate chromatin remodeling, affecting histone acetylation/deacetylation balance. Recently, class I histone deacetylases (HDACs) inhibition has been reported to modulate BDNF mRNA expression and to attenuate morphological and behavioral phenomena related to EtOH exposure. However, the role played by different HDAC isoforms in EtOH-induced plasticity is still unclear. METHODS We investigated the effects induced by acute EtOH exposure on the protein levels of class I HDAC 1-3 isoforms of wild-type (WT) and BDNF heterozygous mice (BDNF(+/-)), in nuclear and cytoplasmic extracts of specific brain regions associated with EtOH addiction. RESULTS Nuclear HDAC 1-3 levels were markedly reduced after acute EtOH treatment in the caudate putamen (CPu) of WT mice only. Furthermore, CPu basal levels of nuclear HDAC isoforms were significantly lower in BDNF(+/-) mice compared to WT. With the exception of nuclear HDAC 3, no significant changes were observed after acute EtOH treatment in the prefrontal cortex (PFCx) of BDNF(+/-) and WT mice. In this area, the nuclear HDAC basal levels were significantly different between the two experimental groups. CONCLUSIONS These results provide details about EtOH effects on class I HDAC isoforms and strongly support a correlation between BDNF and class I HDACs, suggesting a possible influence of BNDF on these enzymes.
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Dasmahapatra AK, Khan IA. DNA methyltransferase expressions in Japanese rice fish (Oryzias latipes) embryogenesis is developmentally regulated and modulated by ethanol and 5-azacytidine. Comp Biochem Physiol C Toxicol Pharmacol 2015; 176-177:1-9. [PMID: 26183885 DOI: 10.1016/j.cbpc.2015.07.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 07/03/2015] [Accepted: 07/06/2015] [Indexed: 12/18/2022]
Abstract
We aimed to investigate the impact of the epigenome in inducting fetal alcohol spectrum disorder (FASD) phenotypes in Japanese rice fish embryogenesis. One of the significant events in epigenome is DNA methylation which is catalyzed by DNA methyltransferase (DNMT) enzymes. We analyzed DNMT enzyme mRNA expressions in Japanese rice fish development starting from fertilized eggs to hatching and also in embryos exposed for first 48h of development either to ethanol (300mM) or to 5-azacytidine (5-azaC; 2mM), an inhibitor of DNMT enzyme activity. As observed in FASD phenotypes, 5-azaC exposure was able to induce microcephaly and craniofacial cartilage deformities in Japanese rice fish. Moreover, we have observed that expression of DNMTs (dnmt1, dnmt3aa, and dnmt3bb.1) are developmentally regulated; high mRNA copies were found in early stages (1-2day-post-fertilization, dpf), followed by gradual reduction until hatched. In ethanol-treated embryos, compared to controls, dnmt1 mRNA is in reduced level in 2dpf and in enhanced level in 6dpf embryos. While dnmt3aa and 3bb.1 remained unaltered. In contrast, embryos exposed to 5-azaC have an enhanced level of dnmt1 and dnmt3bb.1 mRNAs both in 2 and 6dpf embryos while dnmt3aa is enhanced only in 6dpf embryos. Moreover, endocannabinoid receptor 1a (cnr1a) mRNA which was found to be reduced by ethanol remained unaltered and cnr1b and cnr2 mRNAs, which were remained unaltered by ethanol, were increased significantly by 5-azaC in 6dpf embryos. This study indicates that the craniofacial defects observed in FASD phenotypes are the results of dysregulations in DNMT expressions.
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MESH Headings
- Abnormalities, Drug-Induced/enzymology
- Abnormalities, Drug-Induced/etiology
- Abnormalities, Drug-Induced/genetics
- Animals
- Azacitidine/toxicity
- DNA (Cytosine-5-)-Methyltransferase 1
- DNA (Cytosine-5-)-Methyltransferases/genetics
- DNA (Cytosine-5-)-Methyltransferases/metabolism
- DNA Methylation
- DNA Methyltransferase 3A
- Disease Models, Animal
- Epigenesis, Genetic/drug effects
- Ethanol/toxicity
- Fetal Alcohol Spectrum Disorders/enzymology
- Fetal Alcohol Spectrum Disorders/etiology
- Fetal Alcohol Spectrum Disorders/genetics
- Fish Proteins/genetics
- Fish Proteins/metabolism
- Gene Expression Regulation, Enzymologic
- Oryzias/embryology
- Oryzias/genetics
- Oryzias/metabolism
- RNA, Messenger/metabolism
- Receptor, Cannabinoid, CB1/drug effects
- Receptor, Cannabinoid, CB1/genetics
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/drug effects
- Receptor, Cannabinoid, CB2/genetics
- Receptor, Cannabinoid, CB2/metabolism
- Time Factors
- DNA Methyltransferase 3B
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Affiliation(s)
- Asok K Dasmahapatra
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, University, MS, USA; Department of BioMolecular Sciences, Division of Pharmacology, University of Mississippi, University, MS, USA.
| | - Ikhlas A Khan
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, University, MS, USA; Department of BioMolecular Sciences, Division of Pharmacology, University of Mississippi, University, MS, USA
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68
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Varadinova M, Boyadjieva N. Epigenetic mechanisms: A possible link between autism spectrum disorders and fetal alcohol spectrum disorders. Pharmacol Res 2015; 102:71-80. [PMID: 26408203 DOI: 10.1016/j.phrs.2015.09.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 09/12/2015] [Accepted: 09/13/2015] [Indexed: 01/26/2023]
Abstract
The etiology of autism spectrum disorders (ASDs) still remains unclear and seems to involve a considerable overlap between polygenic, epigenetic and environmental factors. We have summarized the current understanding of the interplay between gene expression dysregulation via epigenetic modifications and the potential epigenetic impact of environmental factors in neurodevelopmental deficits. Furthermore, we discuss the scientific controversies of the relationship between prenatal exposure to alcohol and alcohol-induced epigenetic dysregulations, and gene expression alterations which are associated with disrupted neural plasticity and causal pathways for ASDs. The review of the literature suggests that a better understanding of developmental epigenetics should contribute to furthering our comprehension of the etiology and pathogenesis of ASDs and fetal alcohol spectrum disorders.
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Affiliation(s)
- Miroslava Varadinova
- Department of Pharmacology and Toxicology, Medical Faculty, Medical University, Sofia, Bulgaria.
| | - Nadka Boyadjieva
- Department of Pharmacology and Toxicology, Medical Faculty, Medical University, Sofia, Bulgaria.
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69
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Koob GF. The dark side of emotion: the addiction perspective. Eur J Pharmacol 2015; 753:73-87. [PMID: 25583178 PMCID: PMC4380644 DOI: 10.1016/j.ejphar.2014.11.044] [Citation(s) in RCA: 232] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 11/06/2014] [Accepted: 11/26/2014] [Indexed: 01/04/2023]
Abstract
Emotions are "feeling" states and classic physiological emotive responses that are interpreted based on the history of the organism and the context. Motivation is a persistent state that leads to organized activity. Both are intervening variables and intimately related and have neural representations in the brain. The present thesis is that drugs of abuse elicit powerful emotions that can be interwoven conceptually into this framework. Such emotions range from pronounced euphoria to a devastating negative emotional state that in the extreme can create a break with homeostasis and thus an allostatic hedonic state that has been considered key to the etiology and maintenance of the pathophysiology of addiction. Drug addiction can be defined as a three-stage cycle-binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation-that involves allostatic changes in the brain reward and stress systems. Two primary sources of reinforcement, positive and negative reinforcement, have been hypothesized to play a role in this allostatic process. The negative emotional state that drives negative reinforcement is hypothesized to derive from dysregulation of key neurochemical elements involved in the brain incentive salience and stress systems. Specific neurochemical elements in these structures include not only decreases in incentive salience system function in the ventral striatum (within-system opponent processes) but also recruitment of the brain stress systems mediated by corticotropin-releasing factor (CRF), dynorphin-κ opioid systems, and norepinephrine, vasopressin, hypocretin, and substance P in the extended amygdala (between-system opponent processes). Neuropeptide Y, a powerful anti-stress neurotransmitter, has a profile of action on compulsive-like responding for drugs similar to a CRF1 receptor antagonist. Other stress buffers include nociceptin and endocannabinoids, which may also work through interactions with the extended amygdala. The thesis argued here is that the brain has specific neurochemical neurocircuitry coded by the hedonic extremes of pleasant and unpleasant emotions that have been identified through the study of opponent processes in the domain of addiction. These neurochemical systems need to be considered in the context of the framework that emotions involve the specific brain regions now identified to differentially interpreting emotive physiological expression.
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Affiliation(s)
- George F Koob
- National Institute on Alcohol Abuse and Alcoholism, Washington, DC, USA.
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70
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Ethanol-induced epigenetic regulations at the Bdnf gene in C57BL/6J mice. Mol Psychiatry 2015; 20:405-12. [PMID: 24776738 DOI: 10.1038/mp.2014.38] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 02/12/2014] [Accepted: 03/17/2014] [Indexed: 02/06/2023]
Abstract
High ethanol intake is well known to induce both anxiolytic and anxiogenic effects, in correlation with chromatin remodeling in the amygdaloid brain region and deficits in cell proliferation and survival in the hippocampus of rodents. Whether only moderate but chronic ethanol intake in C57BL/6J mice could also have an impact on chromatin remodeling and neuroplasticity was addressed here. Chronic ethanol consumption in a free choice paradigm was found to induce marked changes in the expression of genes implicated in neural development and histone post-translational modifications in the mouse hippocampus. Transcripts encoding neural bHLH activators and those from Bdnf exons II, III and VI were upregulated, whereas those from Bdnf exon VIII and Hdacs were downregulated by ethanol compared with water consumption. These ethanol-induced changes were associated with enrichment in both acetylated H3 at Bdnf promoter PVI and trimethylated H3 at PII and PIII. Conversely, acetylated H3 at PIII and PVIII and trimethylated H3 at PVIII were decreased in ethanol-exposed mice. In parallel, hippocampal brain-derived neurotrophic factor (BDNF) levels and TrkB-mediated neurogenesis in the dentate gyrus were significantly enhanced by ethanol consumption. These results suggest that, in C57BL/6J mice, chronic and moderate ethanol intake produces marked epigenetic changes underlying BDNF overexpression and downstream hippocampal neurogenesis.
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71
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Xu Y, Liu X, Zhang X, Zhang G, Zhang R, Liu T, Hao W. Histone acetylation of the htr3a gene in the prefrontal cortex of Wistar rats regulates ethanol-seeking behavior. Neural Regen Res 2015; 7:1021-8. [PMID: 25722691 PMCID: PMC4341274 DOI: 10.3969/j.issn.1673-5374.2012.13.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 03/24/2012] [Indexed: 11/21/2022] Open
Abstract
Previous reports showed that decreased histone deacetylase activity significantly potentiated the rewarding effects of psychostimulants, and that encoding of the 5-HT3 receptor by the htr3a gene was related to ethanol-seeking behavior. However, the effects of a histone deacetylase inhibitor on ethanol-seeking behavior and epigenetic regulation of htr3a mRNA expression after chronic ethanol exposure are not fully understood. Using quantitative reverse transcription-polymerase chain reaction and chromatin immunoprecipitation analysis, we investigated the effects of chronic ethanol exposure and its interaction with a histone deacetylase inhibitor on histone-acetylation-mediated changes in htr3a mRNA expression in the htr3a promoter region. The conditioned place preference procedure was used to evaluate ethanol-seeking behavior. Chronic exposure to ethanol effectively elicited place conditioning. In the prefrontal cortex, the acetylation of H3K9 and htr3a mRNA expression in the htr3a promoter region were significantly higher in the ethanol group than in the saline group. The histone deacetylase inhibitor sodium butyrate potentiated the effects of ethanol on htr3a mRNA expression and enhanced ethanol-induced conditioned place preferences. These results suggest that ethanol upregulates htr3a levels through mechanisms involving H3K9 acetylation, and that histone acetylation may be a therapeutic target for treating ethanol abuse.
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Affiliation(s)
- Yahui Xu
- Mental Health Institute, Second Xiangya Hospital, Central South University, Changsha 410011, Hunan Province, China
| | - Xuebing Liu
- Mental Health Institute, Second Xiangya Hospital, Central South University, Changsha 410011, Hunan Province, China
| | - Xiaojie Zhang
- Townsend Family Laboratories, Graduate Program in Neuroscience University of British, Columbia 2255 Wesbrook Mall, Vancouver, B.C. V6T 1Z3, Canada
| | - Guanbai Zhang
- Mental Health Institute, Second Xiangya Hospital, Central South University, Changsha 410011, Hunan Province, China
| | - Ruiling Zhang
- Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453003, Henan Province, China
| | - Tieqiao Liu
- Mental Health Institute, Second Xiangya Hospital, Central South University, Changsha 410011, Hunan Province, China
| | - Wei Hao
- Mental Health Institute, Second Xiangya Hospital, Central South University, Changsha 410011, Hunan Province, China ; Second Affiliated Hospital of Xinxiang Medical University, Xinxiang 453003, Henan Province, China
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72
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Dominguez G, Dagnas M, Decorte L, Vandesquille M, Belzung C, Béracochéa D, Mons N. Rescuing prefrontal cAMP-CREB pathway reverses working memory deficits during withdrawal from prolonged alcohol exposure. Brain Struct Funct 2014; 221:865-77. [PMID: 25388276 DOI: 10.1007/s00429-014-0941-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 11/03/2014] [Indexed: 11/26/2022]
Abstract
Both human and animal studies indicate that alcohol withdrawal following chronic alcohol consumption (CAC) impairs many of the cognitive functions which rely on the prefrontal cortex (PFC). A candidate signaling cascade contributing to memory deficits during alcohol withdrawal is the protein kinase A (PKA)/cAMP-responsive element binding (CREB) cascade, although the role of PKA/CREB cascade in behavioral and molecular changes during sustained withdrawal period remains largely unknown. We demonstrated that 1 week (1W) or 6 weeks (6W) withdrawal after 6-month CAC impairs working memory (WM) in a T-maze spontaneous alternation task and reduces phosphorylated CREB (pCREB) in the PFC but not the dorsal CA1 region (dCA1) of the hippocampus compared with CAC and water conditions. In contrast, both CAC-unimpaired and withdrawn-impaired mice exhibited decreased pCREB in dCA1 as well as reduced histone H4 acetylation in PFC and dCA1, compared with water controls. Next, we showed that enhancing CREB activity through rolipram administration prior to testing improved WM performance in withdrawn mice but impaired WM function in water mice. In addition, WM improvement correlates positively with increased pCREB level selectively in the PFC of withdrawn mice. Results further indicate that direct infusion of the PKA activator (Sp-cAMPS) into the PFC significantly improves or impairs, respectively, WM performance in withdrawn and water animals. In contrast, Sp-cAMPS had no effect on WM when infused into the dCA1. Collectively, these results provide strong support that dysregulation of PKA/CREB-dependent processes in prefrontal neurons is a critical molecular signature underlying cognitive decline during alcohol withdrawal.
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Affiliation(s)
- G Dominguez
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Nouvelle Université de Bordeaux, CNRS UMR 5287, Talence, France
- U-930 Inserm, Université François Rabelais, Parc Grandmont, Tours, France
| | - M Dagnas
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Nouvelle Université de Bordeaux, CNRS UMR 5287, Talence, France
| | - L Decorte
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Nouvelle Université de Bordeaux, CNRS UMR 5287, Talence, France
| | - M Vandesquille
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Nouvelle Université de Bordeaux, CNRS UMR 5287, Talence, France
| | - C Belzung
- U-930 Inserm, Université François Rabelais, Parc Grandmont, Tours, France
| | - D Béracochéa
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Nouvelle Université de Bordeaux, CNRS UMR 5287, Talence, France
| | - N Mons
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Nouvelle Université de Bordeaux, CNRS UMR 5287, Talence, France.
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73
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Chronic light deprivation inhibits appetitive associative learning induced by ethanol and its respective c-Fos and pCREB expression. Int J Neuropsychopharmacol 2014; 17:1815-30. [PMID: 24905237 DOI: 10.1017/s1461145714000480] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
To address the role of mixed anxiety/mood disorder on appetitive associative learning, we verify whether previous chronic light deprivation changes ethanol-induced conditioned place preference and its respective expression of c-Fos and pCREB, markers of neuronal activity and plasticity. The experimental group was maintained in light deprivation for 24 h for a period of 4 wk. Subsequently, it was adapted to a standard light-dark cycle for 1 wk. As a control, some mice were maintained in standard cycle for a period of 4 wk (Naïve group). Then, all animals were submitted to behavioral tests to assess emotionality: elevated plus maze; open field; and forced swim. After that, they were submitted to ethanol-induced conditioned place preference. Ninety minutes after the place preference test, they were perfused, and their brains processed for c-Fos and pCREB immunohistochemistry. Light deprivation induced anxiety-like trait (elevated plus maze), despair (forced swim), and hyperlocomotion (open field), common features seen in other animal models of depression. Ethanol-induced conditioned place preference was accompanied by increases on c-Fos and pCREB in the hippocampus, prefrontal cortex and striatum. Interestingly, mice previously submitted to light deprivation did not develop either acquisition and/or expression of ethanol-induced conditioned place preference or increases in c-Fos and pCREB. Therefore, chronic light deprivation mimics several behavioral aspects of other animal models of depression. Furthermore, it could be useful to study the neurochemical mechanisms involved in the dual diagnosis. However, given its likely deleterious effects on appetitive associative memory, it should be used with caution to investigate the cognitive aspects related to the dual diagnosis.
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74
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Geil CR, Hayes DM, McClain JA, Liput DJ, Marshall SA, Chen KY, Nixon K. Alcohol and adult hippocampal neurogenesis: promiscuous drug, wanton effects. Prog Neuropsychopharmacol Biol Psychiatry 2014; 54:103-13. [PMID: 24842804 PMCID: PMC4134968 DOI: 10.1016/j.pnpbp.2014.05.003] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 05/01/2014] [Accepted: 05/08/2014] [Indexed: 01/29/2023]
Abstract
Adult neurogenesis is now widely accepted as an important contributor to hippocampal integrity and function but also dysfunction when adult neurogenesis is affected in neuropsychiatric diseases such as alcohol use disorders. Excessive alcohol consumption, the defining characteristic of alcohol use disorders, results in a variety of cognitive and behavioral impairments related wholly or in part to hippocampal structure and function. Recent preclinical work has shown that adult neurogenesis may be one route by which alcohol produces hippocampal neuropathology. Alcohol is a pharmacologically promiscuous drug capable of interfering with adult neurogenesis through multiple mechanisms. This review will discuss the primary mechanisms underlying alcohol-induced changes in adult hippocampal neurogenesis including alcohol's effects on neurotransmitters, CREB and its downstream effectors, and the neurogenic niche.
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Affiliation(s)
| | | | | | | | | | | | - Kimberly Nixon
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, United States.
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75
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Cellular prion protein (PrPC) modulates ethanol-induced behavioral adaptive changes in mice. Behav Brain Res 2014; 271:325-32. [DOI: 10.1016/j.bbr.2014.05.067] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 05/28/2014] [Accepted: 05/31/2014] [Indexed: 12/29/2022]
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76
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Bekdash R, Zhang C, Sarkar D. Fetal alcohol programming of hypothalamic proopiomelanocortin system by epigenetic mechanisms and later life vulnerability to stress. Alcohol Clin Exp Res 2014; 38:2323-30. [PMID: 25069392 DOI: 10.1111/acer.12497] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 05/24/2014] [Indexed: 01/01/2023]
Abstract
Hypothalamic proopiomelanocortin (POMC) neurons, one of the major regulators of the hypothalamic-pituitary-adrenal (HPA) axis, immune functions, and energy homeostasis, are vulnerable to the adverse effects of fetal alcohol exposure (FAE). These effects are manifested in POMC neurons by a decrease in Pomc gene expression, a decrement in the levels of its derived peptide β-endorphin and a dysregulation of the stress response in the adult offspring. The HPA axis is a major neuroendocrine system with pivotal physiological functions and mode of regulation. This system has been shown to be perturbed by prenatal alcohol exposure. It has been demonstrated that the perturbation of the HPA axis by FAE is long-lasting and is linked to molecular, neurophysiological, and behavioral changes in exposed individuals. Recently, we showed that the dysregulation of the POMC system function by FAE is induced by epigenetic mechanisms such as hypermethylation of Pomc gene promoter and an alteration in histone marks in POMC neurons. This developmental programming of the POMC system by FAE altered the transcriptome in POMC neurons and induced a hyperresponse to stress in adulthood. These long-lasting epigenetic changes influenced subsequent generations via the male germline. We also demonstrated that the epigenetic programming of the POMC system by FAE was reversed in adulthood with the application of the inhibitors of DNA methylation or histone modifications. Thus, prenatal environmental influences, such as alcohol exposure, could epigenetically modulate POMC neuronal circuits and function to shape adult behavioral patterns. Identifying specific epigenetic factors in hypothalamic POMC neurons that are modulated by fetal alcohol and target Pomc gene could be potentially useful for the development of new therapeutic approaches to treat stress-related diseases in patients with fetal alcohol spectrum disorders.
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Affiliation(s)
- Rola Bekdash
- Endocrinology Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey; Neuroscience Graduate Program, The State University of New Jersey, New Brunswick, New Jersey
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77
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Finegersh A, Homanics GE. Acute ethanol alters multiple histone modifications at model gene promoters in the cerebral cortex. Alcohol Clin Exp Res 2014; 38:1865-73. [PMID: 24942484 DOI: 10.1111/acer.12465] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 04/08/2014] [Indexed: 11/28/2022]
Abstract
BACKGROUND Ethanol (EtOH) exposure alters gene expression in the cerebral cortex (CCx); however, mechanisms of EtOH-induced gene regulation are not well understood. We hypothesized that EtOH regulates gene expression by differentially altering histone modifications at gene promoters that are up- and down-regulated by EtOH. Such epigenetic mechanisms may ultimately contribute to EtOH-induced neuro-adaptations that underlie tolerance, dependence, and EtOH-use disorders. METHODS Eight-week-old, male C57BL/6J mice were treated with 3 g/kg EtOH (intraperitoneally) or saline and sacrificed 6 hours after injection; the CCx and hippocampus (HC) were immediately removed and flash frozen. Chromatin immunoprecipitation was used to study the association of model gene promoters with histone modifications. Western blot was used to detect global changes in the histone modifications studied. We also used a polymerase chain reaction (PCR) array to identify changes in expression of chromatin-modifying enzymes. RESULTS In CCx, acute EtOH decreased expression of Gad1, Hdac2, and Hdac11, which was associated with decreased histone acetylation at the Gad1 and Hdac2 promoters; we also identified increased expression of Mt1, Mt2, Egr1, which was associated with increased H3K4me3 levels at the Mt2 promoter and decreased H3K27me3 levels at the Mt1 promoter. We identified an increase in global levels of H3K4me3 in CCx as well as a global increase in H3K9ac and H3K14ac in HC. The PCR array identified decreased expression of Csrp2 bp, Hdac2, and Hdac11 as well as increased expression of Kat2b in CCx. CONCLUSIONS Acute EtOH induces chromatin remodeling at model up- and down-regulated genes in CCx. Different patterns of histone modifications at these gene promoters indicate that EtOH may be acting through multiple histone-modifying enzymes to alter gene expression; in particular, differential expression of Kat2b, Hdac2, Hdac11, and Csrp2 bp in CCx may mediate EtOH-induced chromatin remodeling. Additional studies are necessary to determine the relationship between EtOH-induced changes in histone-modifying enzymes, specific EtOH-induced histone modifications, and gene expression.
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Affiliation(s)
- Andrey Finegersh
- Departments of Anesthesiology and Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania
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78
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Postoperative cognitive dysfunction: Involvement of neuroinflammation and neuronal functioning. Brain Behav Immun 2014; 38:202-10. [PMID: 24517920 DOI: 10.1016/j.bbi.2014.02.002] [Citation(s) in RCA: 192] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 01/27/2014] [Accepted: 02/03/2014] [Indexed: 12/27/2022] Open
Abstract
Postoperative cognitive dysfunction (POCD) has been hypothesized to be mediated by surgery-induced inflammatory processes, which may influence neuronal functioning either directly or through modulation of intraneuronal pathways, such as the brain derived neurotrophic factor (BDNF) mediated pathway. To study the time course of post-surgical (neuro)inflammation, changes in the BDNF-pathway and POCD, we subjected 3months old male Wistar rats to abdominal surgery and implanted a jugular vein catheter for timed blood sampling. Cognition, affective behavior and markers for (neuro)inflammation, BDNF and neurogenesis were assessed at 1, 2 and 3weeks following surgery. Rats displayed changes in exploratory activity shortly after surgery, associated with postoperatively elevated IL-6 plasma levels. Spatial learning and memory were temporarily impaired in the first 2weeks following surgery, whereas non-spatial cognitive functions seemed unaffected. Analysis of brain tissue revealed increased neuroinflammation (IL-1B and microgliosis) 7days following surgery, decreased BDNF levels on postoperative day 14 and 21, and decreased neurogenesis until at least 21days following surgery. These findings indicate that in young adult rats only spatial learning and memory is affected by surgery, suggesting hippocampal dependent cognition is especially vulnerable to surgery-induced impairment. The observed differences in time course following surgery and relation to plasma IL-6 suggest cognitive dysfunction and mood changes comprise distinct features of postoperative behavioral impairment. The postoperative changes in neuroinflammation, BDNF and neurogenesis may represent aspects of the underlying mechanism for POCD. Future research should be aimed to elucidate how these players interact.
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Zenki KC, Mussulini BHM, Rico EP, de Oliveira DL, Rosemberg DB. Effects of ethanol and acetaldehyde in zebrafish brain structures: an in vitro approach on glutamate uptake and on toxicity-related parameters. Toxicol In Vitro 2014; 28:822-8. [PMID: 24681127 DOI: 10.1016/j.tiv.2014.03.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 03/14/2014] [Accepted: 03/18/2014] [Indexed: 01/30/2023]
Abstract
Ethanol (EtOH) and its metabolite, acetaldehyde (ALD), induce deleterious effects on central nervous system (CNS). Here we investigate the in vitro toxicity of EtOH and ALD (concentrations of 0.25%, 0.5%, and 1%) in zebrafish brain structures [telencephalon (TE), opticum tectum (OT), and cerebellum (CE)] by measuring the functionality of glutamate transporters, MTT reduction, and extracellular LDH activity. Both molecules decreased the activity of the Na(+)-dependent glutamate transporters in all brain structures. The strongest glutamate uptake inhibition after EtOH exposure was 58% (TE-1%), and after ALD, 91% (CE-1%). The results of MTT assay and LDH released demonstrated that the actions of EtOH and its metabolite are concentration and structure-dependent, in which ALD was more toxic than EtOH. In summary, our findings demonstrate a differential toxicity in vitro of EtOH and ALD in zebrafish brain structures, which can involve changes on glutamatergic parameters. We suggest that this species may be an interesting model for assessing the toxicological actions of alcohol and its metabolite in CNS.
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Affiliation(s)
- Kamila Cagliari Zenki
- Programa de Pós-graduação em Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul. Rua Ramiro Barcelos, 2600-Anexo, 90035-003 Porto Alegre, RS, Brazil.
| | - Ben Hur Marins Mussulini
- Programa de Pós-graduação em Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul. Rua Ramiro Barcelos, 2600-Anexo, 90035-003 Porto Alegre, RS, Brazil
| | - Eduardo Pacheco Rico
- Programa de Pós-graduação em Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul. Rua Ramiro Barcelos, 2600-Anexo, 90035-003 Porto Alegre, RS, Brazil; Instituto Nacional de Ciência e Tecnologia em Excitotoxicidade e Neuroproteção (INCT-EN) 90035-003, Porto Alegre, RS, Brazil
| | - Diogo Lösch de Oliveira
- Programa de Pós-graduação em Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul. Rua Ramiro Barcelos, 2600-Anexo, 90035-003 Porto Alegre, RS, Brazil; Zebrafish Neuroscience Research Consortium (ZNRC), USA
| | - Denis Broock Rosemberg
- Instituto Nacional de Ciência e Tecnologia em Excitotoxicidade e Neuroproteção (INCT-EN) 90035-003, Porto Alegre, RS, Brazil; Zebrafish Neuroscience Research Consortium (ZNRC), USA; Programa de Pós-graduação em Bioquímica Toxicológica, Departamento de Bioquímica e Biologia Molecular, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria. Avenida Roraima, 1000, 97105-900 Santa Maria, RS, Brazil.
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80
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Adenosine and glutamate in neuroglial interaction: implications for circadian disorders and alcoholism. ADVANCES IN NEUROBIOLOGY 2014; 11:103-19. [PMID: 25236726 DOI: 10.1007/978-3-319-08894-5_6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Recent studies have demonstrated that the function of glia is not restricted to the support of neuronal function. In fact, astrocytes are essential for neuronal activity in the brain and play an important role in the regulation of complex behavior. Astrocytes actively participate in synapse formation and brain information processing by releasing and uptaking glutamate, D-serine, adenosine 5'-triphosphate (ATP), and adenosine. In the central nervous system, adenosine-mediated neuronal activity modulates the actions of other neurotransmitter systems. Adenosinergic fine-tuning of the glutamate system in particular has been shown to regulate circadian rhythmicity and sleep, as well as alcohol-related behavior and drinking. Adenosine gates both photic (light-induced) glutamatergic and nonphotic (alerting) input to the circadian clock located in the suprachiasmatic nucleus of the hypothalamus. Astrocytic, SNARE-mediated ATP release provides the extracellular adenosine that drives homeostatic sleep. Acute ethanol increases extracellular adenosine, which mediates the ataxic and hypnotic/sedative effects of alcohol, while chronic ethanol leads to downregulated adenosine signaling that underlies insomnia, a major predictor of relapse. Studies using mice lacking the equilibrative nucleoside transporter 1 have illuminated how adenosine functions through neuroglial interactions involving glutamate uptake transporter GLT-1 [referred to as excitatory amino acid transporter 2 (EAAT2) in human] and possibly water channel aquaporin 4 to regulate ethanol sensitivity, reward-related motivational processes, and alcohol intake.
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81
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Krishnan HR, Sakharkar AJ, Teppen TL, Berkel TDM, Pandey SC. The epigenetic landscape of alcoholism. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2014; 115:75-116. [PMID: 25131543 DOI: 10.1016/b978-0-12-801311-3.00003-2] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Alcoholism is a complex psychiatric disorder that has a multifactorial etiology. Epigenetic mechanisms are uniquely capable of accounting for the multifactorial nature of the disease in that they are highly stable and are affected by environmental factors, including alcohol itself. Chromatin remodeling causes changes in gene expression in specific brain regions contributing to the endophenotypes of alcoholism such as tolerance and dependence. The epigenetic mechanisms that regulate changes in gene expression observed in addictive behaviors respond not only to alcohol exposure but also to comorbid psychopathology such as the presence of anxiety and stress. This review summarizes recent developments in epigenetic research that may play a role in alcoholism. We propose that pharmacologically manipulating epigenetic targets, as demonstrated in various preclinical models, hold great therapeutic potential in the treatment and prevention of alcoholism.
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Affiliation(s)
- Harish R Krishnan
- Department of Psychiatry, University of Illinois at Chicago, Chicago, Illinois, USA; Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois, USA
| | - Amul J Sakharkar
- Department of Psychiatry, University of Illinois at Chicago, Chicago, Illinois, USA; Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois, USA
| | - Tara L Teppen
- Department of Psychiatry, University of Illinois at Chicago, Chicago, Illinois, USA; Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois, USA
| | - Tiffani D M Berkel
- Department of Psychiatry, University of Illinois at Chicago, Chicago, Illinois, USA; Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois, USA
| | - Subhash C Pandey
- Department of Psychiatry, University of Illinois at Chicago, Chicago, Illinois, USA; Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois, USA; Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, Illinois, USA.
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82
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Harlaar N, Hutchison KE. Alcohol and the methylome: design and analysis considerations for research using human samples. Drug Alcohol Depend 2013; 133:305-16. [PMID: 23968814 DOI: 10.1016/j.drugalcdep.2013.07.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 07/26/2013] [Accepted: 07/26/2013] [Indexed: 12/14/2022]
Abstract
BACKGROUND A growing number of studies in human samples have sought to determine whether chronic alcohol use and alcohol use disorders (AUDs) may be associated with epigenetic factors, such as DNA methylation. We review the extant literature in light of some of the challenges that currently affect the design and interpretation of epigenetic research in human samples. METHOD A literature search was used to identify studies that have examined DNA methylation in relation to alcohol use or AUDs in human samples (through July 2013). A total of 22 studies were identified. RESULTS Associations with quantitative or diagnostic phenotypes of alcohol use or AUDs have been reported for several genes. However, all studies to date have relied on relatively small samples and cross-sectional study designs. Additionally, attempts to replicate results have been rare. More generally, research progress is hampered by several issues, including limitations of the technologies used to assess DNA methylation, tissue- and cell-specificity of methylation patterns, the difficulties of relating observed methylation differences at a given locus to a functional effect, and limited knowledge about the molecular mechanisms underlying the effects of alcohol on DNA methylation. CONCLUSIONS Although we share the optimism that epigenetics may lead to new insights into the etiology and pathophysiology of AUDs, the methodological and scientific challenges associated with conducting methylomic research in human samples need to be carefully considered when designing and evaluating such studies.
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Affiliation(s)
- Nicole Harlaar
- University of Colorado Boulder, Boulder, CO 80309-0345, USA.
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83
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Harlaar N, Bryan AD, Thayer RE, Karoly HC, Oien N, Hutchison KE. Methylation of a CpG Site Near the ALDH1A2 Gene is Associated with Loss of Control Over Drinking and Related Phenotypes. Alcohol Clin Exp Res 2013; 38:713-21. [DOI: 10.1111/acer.12312] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Accepted: 09/03/2013] [Indexed: 12/18/2022]
Affiliation(s)
- Nicole Harlaar
- Department of Psychology & Neuroscience; University of Colorado Boulder; Boulder Colorado
| | - Angela D. Bryan
- Department of Psychology & Neuroscience; University of Colorado Boulder; Boulder Colorado
| | - Rachel E. Thayer
- Department of Psychology & Neuroscience; University of Colorado Boulder; Boulder Colorado
| | - Hollis C. Karoly
- Department of Psychology & Neuroscience; University of Colorado Boulder; Boulder Colorado
| | - Niles Oien
- Department of Psychology & Neuroscience; University of Colorado Boulder; Boulder Colorado
| | - Kent E. Hutchison
- Department of Psychology & Neuroscience; University of Colorado Boulder; Boulder Colorado
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84
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Positively correlated miRNA-mRNA regulatory networks in mouse frontal cortex during early stages of alcohol dependence. BMC Genomics 2013; 14:725. [PMID: 24148570 PMCID: PMC3924350 DOI: 10.1186/1471-2164-14-725] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 10/04/2013] [Indexed: 01/06/2023] Open
Abstract
Background Although the study of gene regulation via the action of specific microRNAs (miRNAs) has experienced a boom in recent years, the analysis of genome-wide interaction networks among miRNAs and respective targeted mRNAs has lagged behind. MicroRNAs simultaneously target many transcripts and fine-tune the expression of genes through cooperative/combinatorial targeting. Therefore, they have a large regulatory potential that could widely impact development and progression of diseases, as well as contribute unpredicted collateral effects due to their natural, pathophysiological, or treatment-induced modulation. We support the viewpoint that whole mirnome-transcriptome interaction analysis is required to better understand the mechanisms and potential consequences of miRNA regulation and/or deregulation in relevant biological models. In this study, we tested the hypotheses that ethanol consumption induces changes in miRNA-mRNA interaction networks in the mouse frontal cortex and that some of the changes observed in the mouse are equivalent to changes in similar brain regions from human alcoholics. Results miRNA-mRNA interaction networks responding to ethanol insult were identified by differential expression analysis and weighted gene coexpression network analysis (WGCNA). Important pathways (coexpressed modular networks detected by WGCNA) and hub genes central to the neuronal response to ethanol are highlighted, as well as key miRNAs that regulate these processes and therefore represent potential therapeutic targets for treating alcohol addiction. Importantly, we discovered a conserved signature of changing miRNAs between ethanol-treated mice and human alcoholics, which provides a valuable tool for future biomarker/diagnostic studies in humans. We report positively correlated miRNA-mRNA expression networks that suggest an adaptive, targeted miRNA response due to binge ethanol drinking. Conclusions This study provides new evidence for the role of miRNA regulation in brain homeostasis and sheds new light on current understanding of the development of alcohol dependence. To our knowledge this is the first report that activated expression of miRNAs correlates with activated expression of mRNAs rather than with mRNA downregulation in an in vivo model. We speculate that early activation of miRNAs designed to limit the effects of alcohol-induced genes may be an essential adaptive response during disease progression.
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85
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Wolff JM, Rospenda KM, Richman JA, Liu L, Milner LA. Work-family conflict and alcohol use: examination of a moderated mediation model. J Addict Dis 2013; 32:85-98. [PMID: 23480251 DOI: 10.1080/10550887.2012.759856] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Research consistently documents the negative effects of work-family conflict; however, little research focuses on alcohol use. This study embraces a tension reduction theory of drinking, wherein alcohol use is thought to reduce the negative effects of stress. The purpose of the study was to test a moderated mediation model of the relationship between work-family conflict and alcohol use in a Chicagoland community sample of 998 caregivers. Structural equation models showed that distress mediated the relationship between work-family conflict and alcohol use. Furthermore, tension reduction expectancies of alcohol exacerbated the relationship between distress and alcohol use. The results advance the study of work-family conflict and alcohol use, helping explain this complicated relationship using sophisticated statistical techniques. Implications for theory and practice are discussed.
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Affiliation(s)
- Jennifer M Wolff
- Department of Psychiatry, University of Illinois-Chicago, Chicago, Illinois 60607, USA
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86
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Hyposensitivity to gamma-aminobutyric acid in the ventral tegmental area during alcohol withdrawal: reversal by histone deacetylase inhibitors. Neuropsychopharmacology 2013; 38:1674-84. [PMID: 23474591 PMCID: PMC3717553 DOI: 10.1038/npp.2013.65] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 02/01/2013] [Accepted: 02/21/2013] [Indexed: 11/08/2022]
Abstract
Putative dopaminergic (pDAergic) ventral tegmental area (VTA) neurons have an important role in alcohol addiction. Acute ethanol increases the activity of pDAergic neurons, and withdrawal from repeated ethanol administration produces a decreased sensitivity of pDAergic VTA neurons to GABA. Recent studies show that behavioral changes induced by chronic alcohol are reversed by inhibitors of histone deacetylases (HDACs). Whether HDAC-induced histone modifications regulate changes in GABA sensitivity of VTA pDAergic neurons during withdrawal is unknown. Here, we investigated modulation of withdrawal-induced changes in GABA sensitivity of pDAergic VTA neurons by HDAC inhibitors (HDACi), and also measured the levels of HDAC2, histone (H3-K9) acetylation, and GABA-Aα1 receptor (GABA (A-α1) R) subunit in VTA during ethanol withdrawal. Mice were injected intraperitoneally (ip) with either ethanol (3.5 g/kg) or saline twice daily for 3 weeks. In recordings from pDAergic VTA neurons in brain slices from ethanol-withdrawn mice, sensitivity to GABA (50-500 μM) was reduced. In brain slices from ethanol-withdrawn mice incubated with the HDACi SAHA (vorinostat) or trichostatin A (TSA) for 2 h, the hyposensitivity of pDAergic VTA neurons to GABA was significantly attenuated. There was no effect of TSA or SAHA on GABA sensitivity of pDAergic VTA neurons from saline-treated mice. In addition, ethanol withdrawal was associated with an increase in levels of HDAC2 and a decrease in histone (H3-K9) acetylation and levels of GABA (A-α1) R subunits in the VTA. Therefore, blockade of upregulation of HDAC2 by HDACi normalizes GABA hyposensitivity of pDAergic neurons developed during withdrawal after chronic ethanol treatment, which suggests the possibility that inhibition of HDACs can reverse ethanol-induced neuroadaptational changes in reward circuitry.
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87
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Li H, Tao Y, Ma L, Liu X, Ma L. β-Arrestin-2 inhibits preference for alcohol in mice and suppresses Akt signaling in the dorsal striatum. Neurosci Bull 2013; 29:531-40. [PMID: 23839051 DOI: 10.1007/s12264-013-1350-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 11/15/2012] [Indexed: 01/14/2023] Open
Abstract
In this study, we investigated the role of β-arrestin-2 in alcohol preference using the two-bottle choice and conditioned place preference procedures in wild-type (WT) and β-arrestin-2 knockout (KO) mice. Locomotion and righting reflex tests were performed to test alcohol sensitivity. The possible molecular signals regulated by β-arrestin-2 were analyzed by Western blot. We found that β-arrestin-2 KO mice showed a marked increase in voluntary alcohol consumption without significant differences in preference for saccharin or aversion to quinine. These animals also exhibited higher conditioned place preference scores for alcohol than WT mice. Meanwhile, KO mice showed reduced sensitivity to alcohol and increased blood alcohol clearance. Furthermore, after the free consumption of alcohol, the activities of protein kinase B and glycogen synthase kinase 3β (GSK3β) increased in the dorsal striatum of WT mice, but not in KO mice, which showed high basal activity of Akt in the dorsal striatum. These results suggest that β-arrestin-2 negatively regulates alcohol preference and reward, likely through regulating the activation of signaling pathways including Akt/GSK3β in the dorsal striatum.
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Affiliation(s)
- Haohong Li
- The State Key Laboratory of Medical Neurobiology and the Pharmacology Research Center, Shanghai Medical College, and the Institute of Brain Science, Fudan University, Shanghai, 200032, China
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88
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Kos MZ, Yan J, Dick DM, Agrawal A, Bucholz KK, Rice JP, Johnson EO, Schuckit M, Kuperman S, Kramer J, Goate AM, Tischfield JA, Foroud T, Nurnberger J, Hesselbrock V, Porjesz B, Bierut LJ, Edenberg HJ, Almasy L. Common biological networks underlie genetic risk for alcoholism in African- and European-American populations. GENES, BRAIN, AND BEHAVIOR 2013; 12:532-42. [PMID: 23607416 PMCID: PMC3709451 DOI: 10.1111/gbb.12043] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 01/22/2013] [Accepted: 04/17/2013] [Indexed: 12/19/2022]
Abstract
Alcohol dependence (AD) is a heritable substance addiction with adverse physical and psychological consequences, representing a major health and economic burden on societies worldwide. Genes thus far implicated via linkage, candidate gene and genome-wide association studies (GWAS) account for only a small fraction of its overall risk, with effects varying across ethnic groups. Here we investigate the genetic architecture of alcoholism and report on the extent to which common, genome-wide SNPs collectively account for risk of AD in two US populations, African-Americans (AAs) and European-Americans (EAs). Analyzing GWAS data for two independent case-control sample sets, we compute polymarker scores that are significantly associated with alcoholism (P = 1.64 × 10(-3) and 2.08 × 10(-4) for EAs and AAs, respectively), reflecting the small individual effects of thousands of variants derived from patterns of allelic architecture that are population specific. Simulations show that disease models based on rare and uncommon causal variants (MAF < 0.05) best fit the observed distribution of polymarker signals. When scoring bins were annotated for gene location and examined for constituent biological networks, gene enrichment is observed for several cellular processes and functions in both EA and AA populations, transcending their underlying allelic differences. Our results reveal key insights into the complex etiology of AD, raising the possibility of an important role for rare and uncommon variants, and identify polygenic mechanisms that encompass a spectrum of disease liability, with some, such as chloride transporters and glycine metabolism genes, displaying subtle, modifying effects that are likely to escape detection in most GWAS designs.
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Affiliation(s)
- M Z Kos
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX 78227, USA.
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Chandrasekar R. Alcohol and NMDA receptor: current research and future direction. Front Mol Neurosci 2013; 6:14. [PMID: 23754976 PMCID: PMC3664776 DOI: 10.3389/fnmol.2013.00014] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 05/07/2013] [Indexed: 01/05/2023] Open
Abstract
The brain is one of the major targets of alcohol actions. Most of the excitatory synaptic transmission in the central nervous system is mediated by N-methyl-D-aspartate (NMDA) receptors. However, one of the most devastating effects of alcohol leads to brain shrinkage, loss of nerve cells at specific regions through a mechanism involving excitotoxicity, oxidative stress. Earlier studies have indicated that chronic exposure to ethanol both in vivo and in vitro, increases NR1 and NR2B gene expression and their polypeptide levels. The effect of alcohol and molecular changes on the regulatory process, which modulates NMDAR functions including factors altering transcription, translation, post-translational modifications, and protein expression, as well as those influencing their interactions with different regulatory proteins (downstream effectors) are incessantly increasing at the cellular level. Further, I discuss the various genetically altered mice approaches that have been used to study NMDA receptor subunits and their functional implication. In a recent countable review, epigenetic dimension (i.e., histone modification-induced chromatin remodeling and DNA methylation, in the process of alcohol related neuroadaptation) is one of the key molecular mechanisms in alcohol mediated NMDAR alteration. Here, I provide a recount on what has already been achieved, current trends and how the future research/studies of the NMDA receptor might lead to even greater engagement with many possible new insights into the neurobiology and treatment of alcoholism.
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Affiliation(s)
- Raman Chandrasekar
- Department of Biochemistry and Biotechnology Core Facility, Kansas State University Manhattan, KS, USA
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90
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Decreased expression of nardilysin in SH-SY5Y cells under ethanol stress and reduced density of nardilysin-expressing neurons in brains of alcoholics. J Psychiatr Res 2013; 47:343-9. [PMID: 23219461 DOI: 10.1016/j.jpsychires.2012.11.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Revised: 10/05/2012] [Accepted: 11/09/2012] [Indexed: 11/23/2022]
Abstract
There is evidence for a genetic link between the metalloendopeptidase nardilysin and alcohol dependence, but the functional implication of the enzyme in alcoholism is unknown. Interestingly, some of the enzyme's substrates and interaction partners are altered in neural and non-neural tissues under the influence of ethanol consumption. To learn more about putative roles of nardilysin in alcohol dependence we studied the expression of the enzyme protein in human neuroblastoma cells under chronic ethanol exposure as well as in four brain regions of alcoholics and matched controls. Cultured SH-SY5Y cells were exposed for 96 h to two different concentrations of ethanol (50 and 200 mM). Nardilysin expression was determined using Western blotting with densitometric analysis. Furthermore, we morphometrically studied the cellular expression of nardilysin in postmortem brains of eight chronic alcoholics and nine controls by counting the number of nardilysin-immunopositive neurons in left frontal limbic area, Nuc. basalis of Meynert, paraventricular and supraoptic hypothalamic nuclei and calculating numerical cell densities. Nardilysin expression was significantly reduced after 96 h of SH-SY5Y cells exposure to 200 mM ethanol. In human brains nardilysin protein was localized to multiple neurons. In heavy drinkers there was a significantly reduced density of nardilysin immunoreactive neurons in Nuc. basalis of Meynert, paraventricular, and supraoptic nuclei. The alcohol-dependent reduction of nardilysin in cell culture and nervous tissue points to an implication of the enzyme in the pathophysiology of alcoholism.
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91
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Alcohol modulates expression of DNA methyltranferases and methyl CpG-/CpG domain-binding proteins in murine embryonic fibroblasts. Reprod Toxicol 2013; 37:40-8. [PMID: 23395981 DOI: 10.1016/j.reprotox.2013.01.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 12/23/2012] [Accepted: 01/23/2013] [Indexed: 12/14/2022]
Abstract
Fetal alcohol syndrome (FAS), presenting with a constellation of neuro-/psychological, craniofacial and cardiac abnormalities, occurs frequently in offspring of women who consume alcohol during pregnancy, with a prevalence of 1-3 per 1000 livebirths. The present study was designed to test the hypothesis that alcohol alters global DNA methylation, and modulates expression of the DNA methyltransferases (DNMTs) and various methyl CpG-binding proteins. Murine embryonic fibroblasts (MEFs), utilized as an in vitro embryonic model system, demonstrated ∼5% reduction in global DNA methylation following exposure to 200mM ethanol. In addition, ethanol induced degradation of DNA methyltransferases (DNMT-1, DNMT-3a, and DNMT-3b), as well as the methyl CpG-binding proteins (MeCP-2, MBD-2 and MBD-3), in MEF cells by the proteasomal pathway. Such degradation could be completely rescued by pretreatment of MEF cells with the proteasomal inhibitor, MG-132. These data support a potential epigenetic molecular mechanism underlying the pathogenesis of FAS during mammalian development.
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92
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Ponomarev I. Epigenetic control of gene expression in the alcoholic brain. Alcohol Res 2013; 35:69-76. [PMID: 24313166 PMCID: PMC3860426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Chronic alcohol exposure causes widespread changes in brain gene expression in humans and animal models. Many of these contribute to cellular adaptations that ultimately lead to behavioral tolerance and alcohol dependence. There is an emerging appreciation for the role of epigenetic processes in alcohol-induced changes in brain gene expression and behavior. For example, chronic alcohol exposure produces changes in DNA and histone methylation, histone acetylation, and microRNA expression that affect expression of multiple genes in various types of brain cells (i.e., neurons and glia) and contribute to brain pathology and brain plasticity associated with alcohol abuse and dependence. Drugs targeting the epigenetic "master regulators" are emerging as potential therapeutics for neurodegenerative disorders and drug addiction.
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93
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Bell RL, Sable HJ, Colombo G, Hyytia P, Rodd ZA, Lumeng L. Animal models for medications development targeting alcohol abuse using selectively bred rat lines: neurobiological and pharmacological validity. Pharmacol Biochem Behav 2012; 103:119-55. [PMID: 22841890 PMCID: PMC3595005 DOI: 10.1016/j.pbb.2012.07.007] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Revised: 07/07/2012] [Accepted: 07/18/2012] [Indexed: 02/04/2023]
Abstract
The purpose of this review paper is to present evidence that rat animal models of alcoholism provide an ideal platform for developing and screening medications that target alcohol abuse and dependence. The focus is on the 5 oldest international rat lines that have been selectively bred for a high alcohol-consumption phenotype. The behavioral and neurochemical phenotypes of these rat lines are reviewed and placed in the context of the clinical literature. The paper presents behavioral models for assessing the efficacy of pharmaceuticals for the treatment of alcohol abuse and dependence in rodents, with particular emphasis on rats. Drugs that have been tested for their effectiveness in reducing alcohol/ethanol consumption and/or self-administration by these rat lines and their putative site of action are summarized. The paper also presents some current and future directions for developing pharmacological treatments targeting alcohol abuse and dependence.
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Affiliation(s)
- Richard L. Bell
- Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Helen J.K. Sable
- Department of Psychology, University of Memphis, Memphis, Tennessee, USA
| | - Giancarlo Colombo
- Neuroscience Institute, National Research Council of Italy, Section of Cagliari, Monserrato, Italy
| | - Petri Hyytia
- Institute of Biomedicine, University of Helsinki, Finland
| | - Zachary A. Rodd
- Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Lawrence Lumeng
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA
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94
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Contet C. Gene Expression Under the Influence: Transcriptional Profiling of Ethanol in the Brain. CURRENT PSYCHOPHARMACOLOGY 2012; 1:301-314. [PMID: 24078902 PMCID: PMC3783024 DOI: 10.2174/2211556011201040301] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Sensitivity to ethanol intoxication, propensity to drink ethanol and vulnerability to develop alcoholism are all influenced by genetic factors. Conversely, exposure to ethanol or subsequent withdrawal produce gene expression changes, which, in combination with environmental variables, may participate in the emergence of compulsive drinking and relapse. The present review offers an integrated perspective on brain gene expression profiling in rodent models of predisposition to differential ethanol sensitivity or consumption, in rats and mice subjected to acute or chronic ethanol exposure, as well as in human alcoholics. The functional categories over-represented among differentially expressed genes suggest that the transcriptional effects of chronic ethanol consumption contribute to the neuroplasticity and neurotoxicity characteristic of alcoholism. Importantly, ethanol produces distinct transcriptional changes within the different brain regions involved in intoxication, reinforcement and addiction. Special emphasis is put on recent profiling studies that have provided some insights into the molecular mechanisms potentially mediating genome-wide regulation of gene expression by ethanol. In particular, current evidence for a role of transcription factors, chromatin remodeling and microRNAs in coordinating the expression of large sets of genes in animals predisposed to excessive ethanol drinking or exposed to protracted abstinence, as well as in human alcoholics, is presented. Finally, studies that have compared ethanol with other drugs of abuse have highlighted common gene expression patterns that may play a central role in drug addiction. The availability of novel technologies and a focus on mechanistic approaches are shaping the future of ethanol transcriptomics.
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Affiliation(s)
- Candice Contet
- The Scripps Research Institute, Committee on the Neurobiology of Addictive Disorders, La Jolla, CA, USA
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95
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Kashem MA, Ahmed S, Sarker R, Ahmed EU, Hargreaves GA, McGregor IS. Long-term daily access to alcohol alters dopamine-related synthesis and signaling proteins in the rat striatum. Neurochem Int 2012; 61:1280-8. [PMID: 22995788 DOI: 10.1016/j.neuint.2012.08.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 08/23/2012] [Accepted: 08/30/2012] [Indexed: 01/24/2023]
Abstract
Chronic alcohol exposure can adversely affect neuronal morphology, synaptic architecture and associated neuroplasticity. However, the effects of moderate levels of long-term alcohol intake on the brain are a matter of debate. The current study used 2-DE (two-dimensional gel electrophoresis) proteomics to examine proteomic changes in the striatum of male Wistar rats after 8 months of continuous access to a standard off-the-shelf beer in their home cages. Alcohol intake under group-housed conditions during this time was around 3-4 g/kg/day, a level below that known to induce physical dependence in rats. After 8 months of access rats were euthanased and 2-DE proteomic analysis of the striatum was conducted. A total of 28 striatal proteins were significantly altered in the beer drinking rats relative to controls. Strikingly, many of these were dopamine (DA)-related proteins, including tyrosine hydroxylase (an enzyme of DA biosynthesis), pyridoxal phosphate phosphatase (a co-enzyme in DA biosynthesis), DA and cAMP regulating phosphoprotein (a regulator of DA receptors and transporters), protein phosphatase 1 (a signaling protein) and nitric oxide synthase (which modulates DA uptake). Selected protein expression changes were verified using Western blotting. We conclude that long-term moderate alcohol consumption is associated with substantial alterations in the rat striatal proteome, particularly with regard to dopaminergic signaling pathways. This provides potentially important evidence of major neuroadaptations in dopamine systems with daily alcohol consumption at relatively modest levels.
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Affiliation(s)
- Mohammed Abul Kashem
- Psychopharmacology and Proteomics Laboratory, School of Psychology, The University of Sydney, NSW 2006, Australia.
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96
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Kapfhamer D, Taylor S, Zou ME, Lim JP, Kharazia V, Heberlein U. Taok2 controls behavioral response to ethanol in mice. GENES BRAIN AND BEHAVIOR 2012; 12:87-97. [PMID: 22883308 DOI: 10.1111/j.1601-183x.2012.00834.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Revised: 05/30/2012] [Accepted: 08/02/2012] [Indexed: 01/27/2023]
Abstract
Despite recent advances in the understanding of ethanol's biological action, many of the molecular targets of ethanol and mechanisms behind ethanol's effect on behavior remain poorly understood. In an effort to identify novel genes, the products of which regulate behavioral responses to ethanol, we recently identified a mutation in the dtao gene that confers resistance to the locomotor stimulating effect of ethanol in Drosophila. dtao encodes a member of the Ste20 family of serine/threonine kinases implicated in MAP kinase signaling pathways. In this study, we report that conditional ablation of the mouse dtao homolog, Taok2, constitutively and specifically in the nervous system, results in strain-specific and overlapping alterations in ethanol-dependent behaviors. These data suggest a functional conservation of dtao and Taok2 in mediating ethanol's biological action and identify Taok2 as a putative candidate gene for ethanol use disorders in humans.
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Affiliation(s)
- D Kapfhamer
- The Ernest Gallo Clinic and Research Center, University of California at San Francisco, Emeryville, CA 94608, USA.
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97
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Wen RT, Zhang M, Qin WJ, Liu Q, Wang WP, Lawrence AJ, Zhang HT, Liang JH. The phosphodiesterase-4 (PDE4) inhibitor rolipram decreases ethanol seeking and consumption in alcohol-preferring Fawn-Hooded rats. Alcohol Clin Exp Res 2012; 36:2157-67. [PMID: 22671516 DOI: 10.1111/j.1530-0277.2012.01845.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 03/15/2012] [Indexed: 11/29/2022]
Abstract
BACKGROUND Alcohol dependence is a complex psychiatric disorder demanding development of novel pharmacotherapies. Because the cyclic adenosine monophosphate (cAMP) signaling cascade has been implicated in mediating behavioral responses to alcohol, key components in this cascade may serve as potential treatment targets. Phosphodiesterase-4 (PDE4), an enzyme that specifically catalyzes the hydrolysis of cAMP, represents a key point in regulating intracellular cAMP levels. Thus, it was of interest to determine whether PDE4 was involved in the regulation of alcohol use and abuse. METHODS Male Fawn-Hooded (FH/Wjd) rats were tested for 5% (v/v) ethanol (EtOH) and 10% (w/v) sucrose operant oral self-administration following treatment with the selective PDE4 inhibitor rolipram (0.0125, 0.025, or 0.05 mg/kg, subcutaneous [s.c.]); rolipram at higher doses (0.05, 0.1, and 0.2 mg/kg, s.c.) was tested to determine its impact on the intake of EtOH, sucrose, or water using the 2-bottle choice drinking paradigm. Subsequent open-field testing was performed to evaluate the influence of higher doses of rolipram on locomotor activity. RESULTS Acute administration of rolipram dose-dependently reduced operant self-administration of 5% EtOH, but had no effect on 10% sucrose responding. Time-course assessment revealed significant decreases in EtOH consumption after rolipram (0.1, 0.2 mg/kg) treatment in continuous- and intermittent access to EtOH at 5% or 10%, respectively. Moreover, chronic rolipram treatment time-dependently decreased 5% EtOH consumption and preference during treatment days and after the termination of rolipram administration. Rolipram at the highest doses (0.1 and 0.2 mg/kg) did decrease locomotor activity, but the effect lasted only 10 and 20 minutes, respectively, which did not likely alter long-term EtOH drinking. CONCLUSIONS These results suggest that PDE4 plays a role in alcohol seeking and consumption behavior. Drugs interfering with PDE4 may be a potential pharmacotherapy for alcohol dependence.
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Affiliation(s)
- Rui-Ting Wen
- National Institute on Drug Dependence, Peking University, Beijing, China
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98
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Kim JE, Ji ES, Seo JH, Lee MH, Cho S, Pak YK, Seo TB, Kim CJ. Alcohol exposure induces depression-like behavior by decreasing hippocampal neuronal proliferation through inhibition of the BDNF-ERK pathway in gerbils. Anim Cells Syst (Seoul) 2012. [DOI: 10.1080/19768354.2011.640352] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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99
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D'Sa C, Dileone RJ, Anderson GM, Sinha R. Serum and plasma brain-derived neurotrophic factor (BDNF) in abstinent alcoholics and social drinkers. Alcohol 2012; 46:253-9. [PMID: 22364688 DOI: 10.1016/j.alcohol.2011.12.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Revised: 09/19/2011] [Accepted: 12/14/2011] [Indexed: 02/06/2023]
Abstract
Although the effects of alcohol on brain-derived neurotrophic factor (BDNF) have been extensively studied in rodents, BDNF levels have rarely been measured in abstinent, alcohol-dependent (AD) individuals. Interpretation of reported group comparisons of serum BDNF levels is difficult due to limited information regarding analytical variance, biological variability, and the relative contribution of platelet and plasma pools to serum BDNF. Analytical variance (intra- and inter-assay coefficients of variation) of the enzyme-linked immunosorbent assay (ELISA) was characterized. Within- and between-subject variability, and group differences in serum and plasma BDNF, was assessed on three separate days in 16, 4-week abstinent AD individuals (7M/9F) and 16 social drinkers (SDs; 8M/8F). Significantly higher mean (±sd) serum BDNF levels were observed for the AD group compared to the SD (p = 0.003). No significant difference in mean baseline plasma BDNF levels was observed between AD and SD groups. The low analytical variance, high day-to-day within-individual stability and the high degree of individuality demonstrates the potential clinical utility of measuring serum BDNF levels. The low correlations that we observed between plasma and serum levels are congruent with their representing separate pools of BDNF. The observation of higher basal serum BDNF in the AD group without a concomitant elevation in plasma BDNF levels indicates that the elevated serum BDNF in AD patients is not due to greater BDNF exposure. Further research is warranted to fully elucidate mechanisms underlying this alteration and determine the utility of serum BDNF as a predictor or surrogate marker of chronic alcohol abuse.
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100
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Xu K, Hong KA, Zhou Z, Hauger RL, Goldman D, Sinha R. Genetic modulation of plasma NPY stress response is suppressed in substance abuse: association with clinical outcomes. Psychoneuroendocrinology 2012; 37:554-64. [PMID: 21917383 PMCID: PMC3252459 DOI: 10.1016/j.psyneuen.2011.08.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Revised: 07/08/2011] [Accepted: 08/15/2011] [Indexed: 11/26/2022]
Abstract
BACKGROUND Neuropeptide Y (NPY) is involved in stress regulation. Genetic variations predict plasma NPY and neural correlates of emotion and stress. We examined whether the functional NPY haplotype modulates stress-induced NPY and anxiety responses, and if plasma NPY stress responses are associated with substance dependence outcomes. METHODS Thirty-seven treatment-engaged, abstinent substance dependent (SD) patients and 28 healthy controls (HCs) characterized on NPY diplotypes (HH: high expression; HLLL: intermediate/low expression) were exposed to stress, alcohol/drug cues and neutral relaxing cues, using individualized guided imagery, in a 3-session laboratory experiment. Plasma NPY, heart rate and anxiety were assessed. Patients were prospectively followed for 90-days post-treatment to assess relapse outcomes. RESULTS HH individuals showed significantly lower stress-induced NPY with greater heart rate and anxiety ratings, while the HLLL group showed the reverse pattern of NPY, anxiety and heart rate responses. This differential genetic modulation of NPY stress response was suppressed in the SD group, who showed no stress-related increases in NPY and higher heart rate and greater anxiety, regardless of diplotype. Lower NPY predicted subsequent higher number of days and greater amounts of post-treatment drug use. CONCLUSION These preliminary findings are the first to document chronic drug abuse influences on NPY diplotype expression where NPY diplotype modulation of stress-related plasma NPY, heart rate and anxiety responses was absent in the substance abuse sample. The finding that lower stress-related NPY is predictive of greater relapse severity provides support for therapeutic development of neuropeptide Y targets in the treatment of substance use disorders.
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Affiliation(s)
- Ke Xu
- Department of Psychiatry, School of Medicine, Yale University
| | | | - Zhifeng Zhou
- Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health
| | - Richard L Hauger
- VA Healthcare System and Department of Psychiatry, University of California at San Diego
| | - David Goldman
- Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health
| | - Rajita Sinha
- Department of Psychiatry, School of Medicine, Yale University,Yale Child Study Center, New Haven, CT 06519
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