1
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Stea SG, Grisel JE. β-Endorphin influences sedative and ataxic effects of alcohol. Alcohol 2024; 115:69-77. [PMID: 37741556 DOI: 10.1016/j.alcohol.2023.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 09/07/2023] [Accepted: 09/18/2023] [Indexed: 09/25/2023]
Abstract
Beta-endorphin (β-E) is an opioid peptide linked to the behavioral effects of ethanol. For example, β-E provides negative feedback to inhibit the hypothalamic-pituitary-adrenal (HPA) stress axis, and neuroadaptation of this system to ethanol may facilitate sex differences in disordered drinking. Locomotor sensitivity to ethanol may also influence the risk for addiction; however, the role of β-E in psychomotor effects of ethanol is not fully understood. We examined the role of β-E and sex on locomotor effects of ethanol using adult male and female wild-type C57BL/6J and β-E deficient B6.129S2-Pomctm1Low/J mice in a parallel rod floor apparatus following 0.75 or 2.0 g/kg ethanol. Beginning 15 min after intraperitoneal injection, we recorded foot slips, distance traveled, slips per meter, first instance of immobility, and total time spent off-balance (lying on the floor) over 15 min, and collected blood for analysis of ethanol concentration 60 min after injection. Overall, β-E deficient mice were more sedated and ataxic following ethanol; at the lower dose they slipped more frequently and had a higher rate of slips per meter traveled. At the higher dose, β-E deficient mice were predominantly sedated, slipping less frequently, and traveling less, as well as spending more time off-balance and becoming immobile sooner. Genotype interacted with sex in that male β-E deficient mice slipped more frequently than their female counterparts, suggesting that β-E may elicit sex-dependent effects of ethanol-induced ataxia. Blood ethanol concentration did not differ between any group, suggesting that behavioral differences result from altered sensitivity to ethanol. Our data support the contention that β-E modulates the locomotor effects of ethanol and may influence ataxia in a sex-dependent manner. These findings help elucidate the role of β-E in diverging behavioral responses to ethanol and may aid the development of targeted treatments for alcohol use disorders.
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Affiliation(s)
- Samuel G Stea
- Department of Psychology & Neuroscience Program, Bucknell University, Lewisburg, PA 17837, United States
| | - Judith E Grisel
- Department of Psychology & Neuroscience Program, Bucknell University, Lewisburg, PA 17837, United States.
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2
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The Association of the Hypothalamic-Pituitary-Adrenal Axis with Appetite Regulation in Children with Fetal Alcohol Spectrum Disorders (FASDs). Nutrients 2023; 15:nu15061366. [PMID: 36986097 PMCID: PMC10053353 DOI: 10.3390/nu15061366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/08/2023] [Accepted: 03/09/2023] [Indexed: 03/14/2023] Open
Abstract
Prenatal alcohol exposure causes growth impairment and a wide range of developmental, physical, and cognitive disorders in children, collectively referred to as fetal alcohol spectrum disorders (FASDs). In the course of FASDs, abnormalities can also affect eating behavior and nutritional status, but these problems have received little attention. Therefore, the aim of our study was to determine the levels of hormones involved in the action of the hypothalamic–pituitary–adrenal axis: proopiomelanocortin (POMC), cortisol, and adrenocorticotropic hormone (ACTH), in the serum of patients with FASDs. To our knowledge, none of these hormones studied have yet been evaluated in FASDs to date. We investigated 62 FASD patients and 23 healthy controls by applying an enzyme-linked immunosorbent method (ELISA). Fasting POMC levels were significantly lower in patients with FASDs (10.97 vs. 18,57 ng/mL, p = 0.039) compared to controls. However, there were no differences in cortisol concentrations. Additionally, the sex and subgroup status (fetal alcohol syndrome (FAS), neurobehavioral disorder associated with prenatal alcohol exposure (ND-PAE), and FASD risk) did not affect hormone levels. POMC was positively correlated with some clinical parameters such as age, BMI percentile, carbohydrate biomarkers, and ACTH. A positive correlation was observed between ACTH and cortisol levels, as well as ACTH and cholesterol levels. Data analysis showed no HPA axis abnormalities in the form of elevated serum cortisol and ACTH levels. Differences in POMC concentration may indicate the involvement and/or impairment of central nervous system structures in hormonal alterations in FASD individuals, caused by prenatal alcohol exposure. Hormonal dysregulation in FASDs can contribute to reduced growth and development, as well as many other disturbed processes, including neurological/neurodevelopmental dysfunctions. Further insightful studies involving a larger group of patients are needed to determine the potential impact of the measured hormones.
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3
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Das U, Gangisetty O, Chaudhary S, Tarale P, Rousseau B, Price J, Frazier I, Sarkar DK. Epigenetic insight into effects of prenatal alcohol exposure on stress axis development: Systematic review with meta-analytic approaches. ALCOHOL, CLINICAL & EXPERIMENTAL RESEARCH 2023; 47:18-35. [PMID: 36341762 DOI: 10.1111/acer.14972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 10/26/2022] [Accepted: 11/02/2022] [Indexed: 11/09/2022]
Abstract
We conducted a systematic review with meta-analytic elements using publicly available Gene Expression Omnibus (GEO) datasets to determine the role of epigenetic mechanisms in prenatal alcohol exposure (PAE)-induced hypothalamic-pituitary-adrenal (HPA) axis dysfunctions in offspring. Several studies have demonstrated that PAE has long-term consequences on HPA axis functions in offspring. Some studies determined that alcohol-induced epigenetic alterations during fetal development persist in adulthood. However, additional research is needed to understand the major epigenetic events leading to alcohol-induced teratogenesis of the HPA axis. Our network analysis of GEO datasets identified key pathways relevant to alcohol-mediated histone modifications, DNA methylation, and miRNA involvement associated with PAE-induced alterations of the HPA axis. Our analysis indicated that PAE perturbated the epigenetic machinery to activate corticotrophin-releasing hormone, while it suppressed opioid, glucocorticoid receptor, and circadian clock genes. These results help to further our understanding of the epigenetic basis of alcohol's effects on HPA axis development.
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Affiliation(s)
- Ujjal Das
- Endocrinology Program, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
- Department of Animal Sciences, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - Omkaram Gangisetty
- Endocrinology Program, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
- Department of Animal Sciences, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - Shaista Chaudhary
- Endocrinology Program, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
- Department of Animal Sciences, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - Prashant Tarale
- Endocrinology Program, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
- Department of Animal Sciences, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - Bénédicte Rousseau
- Endocrinology Program, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
- Department of Animal Sciences, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - Julianne Price
- Molecular Neuroscience of Alcohol and Drug Abuse Research Training, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
- Center of Alcohol & Substance Use Studies, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
- Department of Kinesiology & Health, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - Ian Frazier
- Molecular Neuroscience of Alcohol and Drug Abuse Research Training, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
- Center of Alcohol & Substance Use Studies, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
- Department of Kinesiology & Health, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - Dipak K Sarkar
- Endocrinology Program, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
- Department of Animal Sciences, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
- Molecular Neuroscience of Alcohol and Drug Abuse Research Training, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
- Center of Alcohol & Substance Use Studies, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
- Rutgers Endocrinology Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
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4
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Meinhardt MW, Giannone F, Hirth N, Bartsch D, Spampinato SM, Kelsch W, Spanagel R, Sommer WH, Hansson AC. Disrupted circadian expression of beta-arrestin 2 affects reward-related µ-opioid receptor function in alcohol dependence. J Neurochem 2021; 160:454-468. [PMID: 34919270 DOI: 10.1111/jnc.15559] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 12/09/2021] [Accepted: 12/09/2021] [Indexed: 12/13/2022]
Abstract
There is increasing evidence for a daily rhythm of μ-opioid receptor (MOR) efficacy and the development of alcohol dependence. Previous studies show that beta-Arrestin 2 (bArr2) has an impact on alcohol intake, at least partially mediated via modulation of MOR signaling, which in turn mediates the alcohol rewarding effects. Considering the interplay of circadian rhythms on MOR and alcohol dependence, we aimed to investigate bArr2 in alcohol dependence at different time-points of the day/light cycle on the level of bArr2 mRNA (in situ hybridization), MOR availability (receptor autoradiography) and MOR signaling (Damgo-stimulated G-protein coupling) in the nucleus accumbens of alcohol-dependent and non-dependent Wistar rats. Using a microarray data set we found that bArr2, but not bArr1, shows a diurnal transcription pattern in the accumbens of naïve rats with higher expression levels during the active cycle. In three-week abstinent rats, bArr2 is upregulated in the accumbens at the beginning of the active cycle (ZT15), whereas no differences were found at the beginning of the inactive cycle (ZT3), compared to controls. This effect was accompanied with a specific downregulation of MOR binding in the active cycle. Additionally, we detect a higher receptor coupling during the inactive cycle compared to the active cycle in alcohol-dependent animals. Together, we report a daily rhythmicity for bArr2 expression linked to an inverse pattern of MOR, suggesting an involvement for bArr2 on circadian regulation of G-protein coupled receptors in alcohol dependence. The presented data may have implications for the development of novel bArr2-related treatment targets for alcoholism.
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Affiliation(s)
- Marcus W Meinhardt
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Square J5, 68159, Mannheim, Germany.,Department of Molecular Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Square J5, 68159, Mannheim, Germany
| | - Francesco Giannone
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Square J5, 68159, Mannheim, Germany
| | - Nathalie Hirth
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Square J5, 68159, Mannheim, Germany
| | - Dusan Bartsch
- Department of Molecular Biology, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Square J5, 68159, Mannheim, Germany
| | - Santi M Spampinato
- Department of Pharmacy and Biotechnology, University of Bologna, Via Irnerio 48, 40126, Bologna, Italy
| | - Wolfgang Kelsch
- Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Square J5, 68159, Mannheim, Germany
| | - Rainer Spanagel
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Square J5, 68159, Mannheim, Germany
| | - Wolfgang H Sommer
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Square J5, 68159, Mannheim, Germany
| | - Anita C Hansson
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Square J5, 68159, Mannheim, Germany
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5
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Chung DD, Pinson MR, Bhenderu LS, Lai MS, Patel RA, Miranda RC. Toxic and Teratogenic Effects of Prenatal Alcohol Exposure on Fetal Development, Adolescence, and Adulthood. Int J Mol Sci 2021; 22:ijms22168785. [PMID: 34445488 PMCID: PMC8395909 DOI: 10.3390/ijms22168785] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/08/2021] [Accepted: 08/11/2021] [Indexed: 12/12/2022] Open
Abstract
Prenatal alcohol exposure (PAE) can have immediate and long-lasting toxic and teratogenic effects on an individual’s development and health. As a toxicant, alcohol can lead to a variety of physical and neurological anomalies in the fetus that can lead to behavioral and other impairments which may last a lifetime. Recent studies have focused on identifying mechanisms that mediate the immediate teratogenic effects of alcohol on fetal development and mechanisms that facilitate the persistent toxic effects of alcohol on health and predisposition to disease later in life. This review focuses on the contribution of epigenetic modifications and intercellular transporters like extracellular vesicles to the toxicity of PAE and to immediate and long-term consequences on an individual’s health and risk of disease.
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6
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Gangisetty O, Mead EA, Sarkar DK. Sex-Determining Region Y Controls the Effects of Fetal Alcohol Exposure on Proopiomelanocortin Gene Expression. Front Neurosci 2021; 15:608102. [PMID: 33796006 PMCID: PMC8008069 DOI: 10.3389/fnins.2021.608102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Accepted: 02/17/2021] [Indexed: 12/02/2022] Open
Abstract
Fetal alcohol exposure (FAE) causes various neurodevelopmental deficits in offspring, including reduced expression of the stress regulatory proopiomelanocortin (Pomc) gene and an elevated stress response for multiple generations via the male germline. Male germline-specific effects of FAE on the Pomc gene raises the question if the sex-determining region Y (SRY) may have a role in regulating Pomc gene expression. Using a transgenerational model of FAE in Fischer 344 rats, we determined the role of SRY in the regulation of the Pomc gene. FAEs, like on the Pomc gene, reduced Sry gene expression in sperm and the mediobasal hypothalamus (MBH) in male adult offspring. Fetal alcohol-induced inhibition of Sry gene expression was associated with increased Sry promoter DNA methylation. Additionally, fetal alcohol effects on the Sry gene persisted for three generations in the male germline but not in the female germline. Sry gene knockdown reduced the Pomc gene expression. Sry recruitment onto the Pomc promoter was found to be reduced in the hypothalamus of fetal alcohol-exposed rats compared to control rats. Pomc promoter luciferase activity was increased following Sry overexpression. A site-directed mutagenesis study revealed that SRY binding sites are required for POMC promoter transcription activity. Overall, these findings suggest that SRY plays a stimulatory role in the regulation of Pomc gene expression and may potentially contribute to the fetal alcohol-induced changes in the level of Pomc gene expression for multiple generations.
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Affiliation(s)
- Omkaram Gangisetty
- Rutgers Endocrine Research Program, Department of Animal Sciences, Rutgers University, New Brunswick, NJ, United States
| | - Edward A Mead
- Rutgers Endocrine Research Program, Department of Animal Sciences, Rutgers University, New Brunswick, NJ, United States
| | - Dipak K Sarkar
- Rutgers Endocrine Research Program, Department of Animal Sciences, Rutgers University, New Brunswick, NJ, United States
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7
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Demin KA, Taranov AS, Ilyin NP, Lakstygal AM, Volgin AD, de Abreu MS, Strekalova T, Kalueff AV. Understanding neurobehavioral effects of acute and chronic stress in zebrafish. Stress 2021; 24:1-18. [PMID: 32036720 DOI: 10.1080/10253890.2020.1724948] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Stress is a common cause of neuropsychiatric disorders, evoking multiple behavioral, endocrine and neuro-immune deficits. Animal models have been extensively used to understand the mechanisms of stress-related disorders and to develop novel strategies for their treatment. Complementing rodent and clinical studies, the zebrafish (Danio rerio) is one of the most important model organisms in biomedicine. Rapidly becoming a popular model species in stress neuroscience research, zebrafish are highly sensitive to both acute and chronic stress, and show robust, well-defined behavioral and physiological stress responses. Here, we critically evaluate the utility of zebrafish-based models for studying acute and chronic stress-related CNS pathogenesis, assess the advantages and limitations of these aquatic models, and emphasize their relevance for the development of novel anti-stress therapies. Overall, the zebrafish emerges as a powerful and sensitive model organism for stress research. Although these fish generally display evolutionarily conserved behavioral and physiological responses to stress, zebrafish-specific aspects of neurogenesis, neuroprotection and neuro-immune responses may be particularly interesting to explore further, as they may offer additional insights into stress pathogenesis that complement (rather than merely replicate) rodent findings. Compared to mammals, zebrafish models are also characterized by increased availability of gene-editing tools and higher throughput of drug screening, thus being able to uniquely empower translational research of genetic determinants of stress and resilience, as well as to foster innovative CNS drug discovery and the development of novel anti-stress therapies.
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Affiliation(s)
- Konstantin A Demin
- Institute of Experimental Biomedicine, Almazov National Medical Research Center, Ministry of Healthcare of Russian Federation, St. Petersburg, Russia
- Laboratory of Biological Psychiatry, Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia
| | - Alexander S Taranov
- Laboratory of Biological Psychiatry, Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia
- Laboratory of Preclinical Bioscreening, Granov Russian Research Center of Radiology and Surgical Technologies, Ministry of Healthcare of Russian Federation, Pesochny, Russia
| | - Nikita P Ilyin
- Laboratory of Biological Psychiatry, Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia
- Laboratory of Preclinical Bioscreening, Granov Russian Research Center of Radiology and Surgical Technologies, Ministry of Healthcare of Russian Federation, Pesochny, Russia
| | - Anton M Lakstygal
- Laboratory of Biological Psychiatry, Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia
- Laboratory of Preclinical Bioscreening, Granov Russian Research Center of Radiology and Surgical Technologies, Ministry of Healthcare of Russian Federation, Pesochny, Russia
| | - Andrey D Volgin
- Laboratory of Preclinical Bioscreening, Granov Russian Research Center of Radiology and Surgical Technologies, Ministry of Healthcare of Russian Federation, Pesochny, Russia
| | - Murilo S de Abreu
- Bioscience Institute, University of Passo Fundo, Passo Fundo, Brazil
- The International Zebrafish Neuroscience Research Consortium (ZNRC), Slidell, LA, USA
| | - Tatyana Strekalova
- I.M. Sechenov First Moscow State Medical University, Moscow, Russia
- Maastricht University, Maastricht, The Netherlands
- Research Institute of General Pathology and Pathophysiology, Moscow, Russia
| | - Allan V Kalueff
- School of Pharmacy, Southwest University, Chongqing, China
- Ural Federal University, Ekaterinburg, Russia
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8
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Alcohol as an early life stressor: Epigenetics, metabolic, neuroendocrine and neurobehavioral implications. Neurosci Biobehav Rev 2020; 118:654-668. [PMID: 32976915 DOI: 10.1016/j.neubiorev.2020.08.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 05/18/2020] [Accepted: 08/25/2020] [Indexed: 12/14/2022]
Abstract
Ethanol exposure during gestation is an early life stressor that profoundly dysregulates structure and functions of the embryonal nervous system, altering the cognitive and behavioral development. Such dysregulation is also achieved by epigenetic mechanisms, which, altering the chromatin structure, redraw the entire pattern of gene expression. In parallel, an oxidative stress response at the cellular level and a global upregulation of neuroendocrine stress response, regulated by the HPA axis, exist and persist in adulthood. This neurobehavioral framework matches those observed in other psychiatric diseases such as mood diseases, depression, autism; those early life stressing events, although probably triggered by specific and different epigenetic mechanisms, give rise to largely overlapping neurobehavioral phenotypes. An early diagnosis of prenatal alcohol exposure, using reliable markers of ethanol intake, together with a deeper understanding of the pathogenic mechanisms, some of them reversible by their nature, can offer a temporal "window" of intervention. Supplementing a mother's diet with protective and antioxidant substances in addition to supportive psychological therapies can protect newborns from being affected.
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9
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Alcohol Increases Exosome Release from Microglia to Promote Complement C1q-Induced Cellular Death of Proopiomelanocortin Neurons in the Hypothalamus in a Rat Model of Fetal Alcohol Spectrum Disorders. J Neurosci 2020; 40:7965-7979. [PMID: 32887744 DOI: 10.1523/jneurosci.0284-20.2020] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 06/23/2020] [Accepted: 07/20/2020] [Indexed: 02/06/2023] Open
Abstract
Microglia, a type of CNS immune cell, have been shown to contribute to ethanol-activated neuronal death of the stress regulatory proopiomelanocortin (POMC) neuron-producing β-endorphin peptides in the hypothalamus in a postnatal rat model of fetal alcohol spectrum disorders. We determined whether the microglial extracellular vesicle exosome is involved in the ethanol-induced neuronal death of the β-endorphin neuron. Extracellular vesicles were prepared from hypothalamic tissues collected from postnatal rats (both males and females) fed daily with 2.5 mg/kg ethanol or control milk formula for 5 d or from hypothalamic microglia cells obtained from postnatal rats, grown in cultures for several days, and then challenged with ethanol or vehicle for 24 h. Nanoparticle tracking analysis and transmission electron microscopy indicated that these vesicles had the size range and shape of exosomes. Ethanol treatments increased the number and the β-endorphin neuronal killing activity of microglial exosomes both in vivo and in vitro Proteomics analyses of exosomes of cultured microglial cells identified a large number of proteins, including various complements, which were elevated following ethanol treatment. Proteomics data involving complements were reconfirmed using quantitative protein assays. Ethanol treatments also increased deposition of the complement protein C1q in β-endorphin neuronal cells in both in vitro and in vivo systems. Recombinant C1q protein increased while C1q blockers reduced ethanol-induced C3a/b, C4, and membrane attack complex/C5b9 formations; ROS production; and ultimately cellular death of β-endorphin neurons. These data suggest that the complement system involving C1q-C3-C4-membrane attack complex and ROS regulates exosome-mediated, ethanol-induced β-endorphin neuronal death.SIGNIFICANCE STATEMENT Neurotoxic action of alcohol during the developmental period is recognized for its involvement in fetal alcohol spectrum disorders, but the lack of clear understanding of the mechanism of alcohol action has delayed the progress in therapeutic intervention of this disease. Proopiomelanocortin neurons known to regulate stress, energy homeostasis, and immune functions are reported to be killed by developmental alcohol exposure because of activation of microglial immune cells in the brain. While microglia are known to use extracellular vesicles to communicate with neurons for maintaining homeostasis, we show here that ethanol exposure during the developmental period hijacks this system to spread apoptotic factors, including complement protein C1q, to induce the membrane attack complex and reactive super-oxygen species for proopiomelanocortin neuronal killing.
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Miranda-Morales RS, D'Aloisio G, Anunziata F, Abate P, Molina JC. Fetal Alcohol Programming of Subsequent Alcohol Affinity: A Review Based on Preclinical, Clinical and Epidemiological Studies. Front Behav Neurosci 2020; 14:33. [PMID: 32210775 PMCID: PMC7077749 DOI: 10.3389/fnbeh.2020.00033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 02/17/2020] [Indexed: 12/20/2022] Open
Abstract
The anatomo-physiological disruptions inherent to different categories of the Fetal Alcohol Spectrum Disorder do not encompass all the negative consequences derived from intrauterine ethanol (EtOH) exposure. Preclinical, clinical and epidemiological studies show that prenatal EtOH exposure also results in early programming of alcohol affinity. This affinity has been addressed through the examination of how EtOH prenatally exposed organisms recognize and prefer the drug’s chemosensory cues and their predisposition to exhibit heightened voluntary EtOH intake during infancy and adolescence. In altricial species these processes are determined by the interaction of at least three factors during stages equivalent to the 2nd and 3rd human gestational trimester: (i) fetal processing of the drug’s olfactory and gustatory attributes present in the prenatal milieu; (ii) EtOH’s recruitment of central reinforcing effects that also imply progressive sensitization to the drug’s motivational properties; and (iii) an associative learning process involving the prior two factors. This Pavlovian learning phenomenon is dependent upon the recruitment of the opioid system and studies also indicate a significant role of EtOH’s principal metabolite (acetaldehyde, ACD) which is rapidly generated in the brain via the catalase system. The central and rapid accumulation of this metabolite represents a major factor involved in the process of fetal alcohol programming. According to recent investigations, it appears that ACD exerts early positive reinforcing consequences and antianxiety effects (negative reinforcement). Finally, this review also acknowledges human clinical and epidemiological studies indicating that moderate and binge-like drinking episodes during gestation result in neonatal recognition of EtOH’s chemosensory properties coupled with a preference towards these cues. As a whole, the studies under discussion emphasize the notion that even subteratogenic EtOH exposure during fetal life seizes early functional sensory and learning capabilities that pathologically shape subsequent physiological and behavioral reactivity towards the drug.
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Affiliation(s)
- Roberto Sebastián Miranda-Morales
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina.,Facultad de Psicología, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Genesis D'Aloisio
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Florencia Anunziata
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Paula Abate
- Instituto de Investigaciones Psicológicas, Facultad de Psicología, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Juan Carlos Molina
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina.,Facultad de Psicología, Universidad Nacional de Córdoba, Córdoba, Argentina
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11
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Bludau A, Royer M, Meister G, Neumann ID, Menon R. Epigenetic Regulation of the Social Brain. Trends Neurosci 2019; 42:471-484. [PMID: 31103351 DOI: 10.1016/j.tins.2019.04.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 04/10/2019] [Accepted: 04/12/2019] [Indexed: 12/17/2022]
Abstract
Social behavior, a highly adaptive and crucial component of mammalian life, is regulated by particularly sensitive regulatory brain mechanisms. Substantial evidence implicates classical epigenetic mechanisms including histone modifications, DNA methylation, and nucleosome remodeling as well as nonclassical mechanisms mediated by noncoding RNA in the regulation of social behavior. These mechanisms collectively form the 'epigenetic network' that orchestrates genomic integration of salient and transient social experiences. Consequently, its dysregulation has been linked to behavioral deficits and psychopathologies. This review focuses on the role of the epigenetic network in regulating the enduring effects of social experiences during early-life, adolescence, and adulthood. We discuss research in animal models, primarily rodents, and associations between dysregulation of epigenetic mechanisms and human psychopathologies, specifically autism spectrum disorder (ASD) and schizophrenia.
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Affiliation(s)
- Anna Bludau
- Department of Behavioral and Molecular Neurobiology, Regensburg Center of Neuroscience, University of Regensburg, Regensburg, Germany
| | - Melanie Royer
- Department of Behavioral and Molecular Neurobiology, Regensburg Center of Neuroscience, University of Regensburg, Regensburg, Germany; Biochemistry Center Regensburg (BZR), Laboratory of RNA Biology, University of Regensburg, Regensburg, Germany
| | - Gunter Meister
- Biochemistry Center Regensburg (BZR), Laboratory of RNA Biology, University of Regensburg, Regensburg, Germany
| | - Inga D Neumann
- Department of Behavioral and Molecular Neurobiology, Regensburg Center of Neuroscience, University of Regensburg, Regensburg, Germany
| | - Rohit Menon
- Department of Behavioral and Molecular Neurobiology, Regensburg Center of Neuroscience, University of Regensburg, Regensburg, Germany.
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12
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Exposure of pregnant mice to triclosan causes hyperphagic obesity of offspring via the hypermethylation of proopiomelanocortin promoter. Arch Toxicol 2018; 93:547-558. [PMID: 30377736 DOI: 10.1007/s00204-018-2338-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 10/23/2018] [Indexed: 02/06/2023]
Abstract
Triclosan (TCS), as a broad spectrum antibacterial agent, is commonly utilized in personal care and household products. Maternal urinary TCS level has been associated with changes in birth weight of infants. We in the present study investigated whether exposure of mice to 8 mg/kg TCS from gestational day (GD) 6 to GD14 alters prenatal and postnatal growth and development, and metabolic phenotypes in male and female offspring (TCS-offspring). Compared with control offspring, body weight in postnatal day (PND) 1 male or female TCS-offspring was reduced, but body weight gain was faster within postnatal 5 days. PND30 and PND60 TCS-offspring showed overweight with increases in visceral fat and adipocyte size. PND60 TCS-offspring displayed delayed glucose clearance and insulin resistance. PND30 TCS-offspring showed an increase in food intake without the changes in the oxygen consumption and respiratory exchange ratio (RER). The expression levels of proopiomelanocortin (POMC), α-melanocyte-stimulating hormone (α-MSH) and single-minded 1 (SIM1) in hypothalamus arcuate nucleus (ARC) and paraventricular nucleus (PVN), respectively, were significantly reduced in PND30 TCS-offspring compared to controls. The hypermethylation of CpG sites at the POMC promoter was observed in PND30 TCS-offspring, while the concentration of serum leptin was elevated and the level of STAT3 phosphorylation in ARC had no significant difference from control. This study demonstrates that TCS exposure during early/mid-gestation through the hypermethylation of the POMC promoter reduces the expression of anorexigenic neuropeptides to cause the postnatal hyperphagic obesity, leading to metabolic syndrome in adulthood.
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Rachdaoui N, Li L, Willard B, Kasumov T, Previs S, Sarkar D. Turnover of histones and histone variants in postnatal rat brain: effects of alcohol exposure. Clin Epigenetics 2017; 9:117. [PMID: 29075360 PMCID: PMC5654083 DOI: 10.1186/s13148-017-0416-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Accepted: 10/04/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Alcohol consumption during pregnancy is a significant public health problem and can result in a continuum of adverse outcomes to the fetus known as fetal alcohol spectrum disorders (FASD). Subjects with FASD show significant neurological deficits, ranging from microencephaly, neurobehavioral, and mental health problems to poor social adjustment and stress tolerance. Neurons are particularly sensitive to alcohol exposure. The neurotoxic action of alcohol, i.e., through ROS production, induces DNA damage and neuronal cell death by apoptosis. In addition, epigenetics, including DNA methylation, histone posttranslational modifications (PTMs), and non-coding RNA, play an important role in the neuropathology of FASD. However, little is known about the temporal dynamics and kinetics of histones and their PTMs in FASD. RESULTS We examined the effects of postnatal alcohol exposure (PAE), an animal model of human third-trimester equivalent, on the kinetics of various histone proteins in two distinct brain regions, the frontal cortex, and the hypothalamus, using in vivo 2H2O-labeling combined with mass spectrometry-based proteomics. We show that histones have long half-lives that are in the order of days. We also show that H3.3 and H2Az histone variants have faster turnovers than canonical histones and that acetylated histones, in general, have a faster turnover than unmodified and methylated histones. Our work is the first to show that PAE induces a differential reduction in turnover rates of histones in both brain regions studied. These alterations in histone turnover were associated with increased DNA damage and decreased cell proliferation in postnatal rat brain. CONCLUSION Alterations in histone turnover might interfere with histone deposition and chromatin stability, resulting in deregulated cell-specific gene expression and therefore contribute to the development of the neurological disorders associated with FASD. Using in vivo 2H2O-labeling and mass spectrometry-based proteomics might help in the understanding of histone turnover following alcohol exposure and could be of great importance in enabling researchers to identify novel targets and/or biomarkers for the prevention and management of fetal alcohol spectrum disorders.
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Affiliation(s)
- Nadia Rachdaoui
- Department of Animal Sciences, Rutgers Endocrine Research Program, Rutgers, the State University of New Jersey, 67 Poultry Farm Lane, New Brunswick, NJ 08901 USA
| | - Ling Li
- Department of Research Core Services, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106 USA
| | - Belinda Willard
- Department of Research Core Services, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106 USA
| | - Takhar Kasumov
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272 USA
| | - Stephen Previs
- Cardiometabolic Disease, Merck & Co., Inc, Kenilworth, NJ USA
| | - Dipak Sarkar
- Department of Animal Sciences, Rutgers Endocrine Research Program, Rutgers, the State University of New Jersey, 67 Poultry Farm Lane, New Brunswick, NJ 08901 USA
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Shrivastava P, Cabrera MA, Chastain LG, Boyadjieva NI, Jabbar S, Franklin T, Sarkar DK. Mu-opioid receptor and delta-opioid receptor differentially regulate microglial inflammatory response to control proopiomelanocortin neuronal apoptosis in the hypothalamus: effects of neonatal alcohol. J Neuroinflammation 2017; 14:83. [PMID: 28407740 PMCID: PMC5391607 DOI: 10.1186/s12974-017-0844-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 03/19/2017] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Opioid receptors are known to control neurotransmission of various peptidergic neurons, but their potential role in regulation of microglia and neuronal cell communications is unknown. We investigated the role of mu-opioid receptors (MOR) and delta-opioid receptors (DOR) on microglia in the regulation of apoptosis in proopiomelanocortin (POMC) neurons induced by neonatal ethanol in the hypothalamus. METHODS Neonatal rat pups were fed a milk formula containing ethanol or control diets between postnatal days 2-6. Some of the alcohol-fed rats additionally received pretreatment of a microglia activation blocker minocycline. Two hours after the last feeding, some of the pups were sacrificed and processed for histochemical detection of microglial cell functions or confocal microscopy for detection of cellular physical interaction or used for gene and protein expression analysis. The rest of the pups were dissected for microglia separation by differential gradient centrifugation and characterization by measuring production of various activation markers and cytokines. In addition, primary cultures of microglial cells were prepared using hypothalamic tissues of neonatal rats and used for determination of cytokine production/secretion and apoptotic activity of neurons. RESULTS In the hypothalamus, neonatal alcohol feeding elevated cytokine receptor levels, increased the number of microglial cells with amoeboid-type circularity, enhanced POMC and microglial cell physical interaction, and decreased POMC cell numbers. Minocycline reversed these cellular effects of alcohol. Alcohol feeding also increased levels of microglia MOR protein and pro-inflammatory signaling molecules in the hypothalamus, and MOR receptor antagonist naltrexone prevented these effects of alcohol. In primary cultures of hypothalamic microglia, both MOR agonist [D-Ala 2, N-MePhe 4, Gly-ol]-enkephalin (DAMGO) and ethanol increased microglial cellular levels and secretion of pro-inflammatory cell signaling proteins. However, a DOR agonist [D-Pen2,5]enkephalin (DPDPE) increased microglial secretion of anti-inflammatory cytokines and suppressed ethanol's ability to increase microglial production of inflammatory signaling proteins and secretion of pro-inflammatory cytokines. In addition, MOR-activated inflammation promoted while DOR-suppressed inflammation inhibited the apoptotic effect of ethanol on POMC neurons. CONCLUSIONS These results suggest that ethanol's neurotoxic action on POMC neurons results from MOR-activated neuroinflammatory signaling. Additionally, these results identify a protective effect of a DOR agonist against the pro-inflammatory and neurotoxic action of ethanol.
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Affiliation(s)
- Pallavi Shrivastava
- The Endocrine Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, 67 Poultry Lane, New Brunswick, NJ, 08901, USA
| | - Miguel A Cabrera
- The Endocrine Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, 67 Poultry Lane, New Brunswick, NJ, 08901, USA
| | - Lucy G Chastain
- The Endocrine Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, 67 Poultry Lane, New Brunswick, NJ, 08901, USA
| | - Nadka I Boyadjieva
- The Endocrine Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, 67 Poultry Lane, New Brunswick, NJ, 08901, USA
| | - Shaima Jabbar
- The Endocrine Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, 67 Poultry Lane, New Brunswick, NJ, 08901, USA
| | - Tina Franklin
- The Endocrine Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, 67 Poultry Lane, New Brunswick, NJ, 08901, USA
| | - Dipak K Sarkar
- The Endocrine Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, 67 Poultry Lane, New Brunswick, NJ, 08901, USA.
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McGonigle CE, Nentwig TB, Wilson DE, Rhinehart EM, Grisel JE. β-endorphin regulates alcohol consumption induced by exercise restriction in female mice. Alcohol 2016; 53:51-60. [PMID: 27286936 DOI: 10.1016/j.alcohol.2016.04.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Revised: 03/14/2016] [Accepted: 04/25/2016] [Indexed: 10/21/2022]
Abstract
Animal models have long been used to study the mechanisms underlying the complex association between alcohol and stress. Female mice prevented from running on a home-cage activity wheel increase voluntary ethanol consumption. β-endorphin is an endogenous opioid involved in negatively regulating the stress response and has also been implicated in the risk for excessive drinking. The present study investigates the role of β-endorphin in moderating free-choice consumption of ethanol in response to a blocked activity wheel. Female, transgenic mice with varying levels of the opioid peptide were given daily 2-h access to 20% ethanol with rotations on a running wheel blocked on alternate days. Subjects with low β-endorphin exhibited enhanced stress sensitivity by self-administering larger quantities of ethanol on days when wheel running was prevented. β-endorphin levels did not influence voluntary activity on the running wheel. There were genotypic differences in plasma corticosterone levels as well as corticotropin-releasing hormone mRNA content in multiple brain regions associated with the stress response in these free drinking and running subjects. Susceptibility to stress is enhanced in female mice with low levels of β-endorphin, and better understanding of the role for this opioid in mitigating the response to stressors may aid in the development of interventions and treatments for excessive use of alcohol in women.
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Logan RW, Wynne O, Maglakelidze G, Zhang C, O'Connell S, Boyadjieva NI, Sarkar DK. β-Endorphin neuronal transplantation into the hypothalamus alters anxiety-like behaviors in prenatal alcohol-exposed rats and alcohol-non-preferring and alcohol-preferring rats. Alcohol Clin Exp Res 2016; 39:146-57. [PMID: 25623413 DOI: 10.1111/acer.12611] [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: 08/07/2014] [Accepted: 10/22/2014] [Indexed: 11/28/2022]
Abstract
BACKGROUND Alcohol exposure has adverse effects on stress physiology and behavioral reactivity. This is suggested to be due, in part, to the effect of alcohol on β-endorphin (β-EP)-producing neurons in the hypothalamus. In response to stress, β-EP normally provides negative feedback to the hypothalamic-pituitary-adrenal axis and interacts with other neurotransmitter systems in the amygdala to regulate behavior. We examined whether β-EP neuronal function in the hypothalamus reduces the corticosterone response to acute stress, attenuates anxiety-like behaviors, and modulates alcohol drinking in rats. METHODS To determine whether β-EP neuronal transplants modulate the stress response, anxiety behavior, and alcohol drinking, we implanted differentiated β-EP neurons into the paraventricular nucleus (PVN) of the hypothalamus of normal, prenatal alcohol-exposed, and alcohol-preferring (P) and alcohol-non-preferring (NP) rats. We then assessed corticosterone levels in response to acute restraint stress and other markers of stress response in the brain and anxiety-like behaviors in the elevated plus maze and open-field assays. RESULTS We showed that β-EP neuronal transplants into the PVN reduced the peripheral corticosterone response to acute stress and attenuated anxiety-like behaviors. Similar transplants completely reduced the hypercorticosterone response and elevated anxiety behaviors in prenatal alcohol-exposed adult rats. Moreover, we showed that β-EP reduced anxiety behavior in P rats with minimal effects on alcohol drinking during and following restraint stress. CONCLUSIONS These data further establish a role of β-EP neurons in the hypothalamus for regulating physiological stress response and anxiety behavior and resemble a potential novel therapy for treating stress-related psychiatric disorders in prenatal alcohol-exposed children and those genetically predisposed to increased alcohol consumption.
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Affiliation(s)
- Ryan W Logan
- Endocrine Program, Rutgers, The State University of New Jersey, New Brunswick, New Jersey; University of Pittsburgh Medical Center, Department of Psychiatry, Translational Neuroscience Program, Pittsburgh, Pennsylvania
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Wilhelm CJ, Guizzetti M. Fetal Alcohol Spectrum Disorders: An Overview from the Glia Perspective. Front Integr Neurosci 2016; 9:65. [PMID: 26793073 PMCID: PMC4707276 DOI: 10.3389/fnint.2015.00065] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 12/10/2015] [Indexed: 01/30/2023] Open
Abstract
Alcohol consumption during pregnancy can produce a variety of central nervous system (CNS) abnormalities in the offspring resulting in a broad spectrum of cognitive and behavioral impairments that constitute the most severe and long-lasting effects observed in fetal alcohol spectrum disorders (FASD). Alcohol-induced abnormalities in glial cells have been suspected of contributing to the adverse effects of alcohol on the developing brain for several years, although much research still needs to be done to causally link the effects of alcohol on specific brain structures and behavior to alterations in glial cell development and function. Damage to radial glia due to prenatal alcohol exposure may underlie observations of abnormal neuronal and glial migration in humans with Fetal Alcohol Syndrome (FAS), as well as primate and rodent models of FAS. A reduction in cell number and altered development has been reported for several glial cell types in animal models of FAS. In utero alcohol exposure can cause microencephaly when alcohol exposure occurs during the brain growth spurt a period characterized by rapid astrocyte proliferation and maturation; since astrocytes are the most abundant cells in the brain, microenchephaly may be caused by reduced astrocyte proliferation or survival, as observed in in vitro and in vivo studies. Delayed oligodendrocyte development and increased oligodendrocyte precursor apoptosis has also been reported in experimental models of FASD, which may be linked to altered myelination/white matter integrity found in FASD children. Children with FAS exhibit hypoplasia of the corpus callosum and anterior commissure, two areas requiring guidance from glial cells and proper maturation of oligodendrocytes. Finally, developmental alcohol exposure disrupts microglial function and induces microglial apoptosis; given the role of microglia in synaptic pruning during brain development, the effects of alcohol on microglia may be involved in the abnormal brain plasticity reported in FASD. The consequences of prenatal alcohol exposure on glial cells, including radial glia and other transient glial structures present in the developing brain, astrocytes, oligodendrocytes and their precursors, and microglia contributes to abnormal neuronal development, reduced neuron survival and disrupted brain architecture and connectivity. This review highlights the CNS structural abnormalities caused by in utero alcohol exposure and outlines which abnormalities are likely mediated by alcohol effects on glial cell development and function.
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Affiliation(s)
- Clare J Wilhelm
- Research Service, VA Portland Health Care SystemPortland, OR, USA; Department of Psychiatry, Oregon Health and Science UniversityPortland, OR, USA
| | - Marina Guizzetti
- Research Service, VA Portland Health Care SystemPortland, OR, USA; Department of Behavioral Neuroscience, Oregon Health and Science UniversityPortland, OR, USA
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Sarkar DK. Male germline transmits fetal alcohol epigenetic marks for multiple generations: a review. Addict Biol 2016; 21:23-34. [PMID: 25581210 DOI: 10.1111/adb.12186] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Alcohol exposure during fetal and early postnatal development can lead to an increased incidence of later life adult-onset diseases. Examples include central nervous system dysfunction, depression, anxiety, hyperactivity, and an inability to deal with stressful situations, increased infection and cancer. Direct effects of alcohol leading to developmental abnormalities often involve epigenetic modifications of genes that regulate cellular functions. Epigenetic marks carried over from the parents are known to undergo molecular programming events that happen early in embryonic development by a wave of DNA demethylation, which leaves the embryo with a fresh genomic composition. The proopiomelanocortin (Pomc) gene controls neuroendocrine-immune functions and is imprinted by fetal alcohol exposure. Recently, this gene has been shown to be hypermethylated through three generations. Additionally, the alcohol epigenetic marks on the Pomc gene are maintained in the male but not in the female germline during this transgenerational transmission. These data suggest that the male-specific chromosome might be involved in transmitting alcohol epigenetic marks through multiple generations.
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Affiliation(s)
- Dipak K. Sarkar
- Rutgers Endocrine Program; Department of Animal Sciences; Rutgers, The State University of New Jersey; Piscataway Township NJ USA
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19
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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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20
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Chang GQ, Karatayev O, Leibowitz SF. Prenatal exposure to ethanol stimulates hypothalamic CCR2 chemokine receptor system: Possible relation to increased density of orexigenic peptide neurons and ethanol drinking in adolescent offspring. Neuroscience 2015; 310:163-75. [PMID: 26365610 DOI: 10.1016/j.neuroscience.2015.09.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 09/03/2015] [Accepted: 09/07/2015] [Indexed: 12/14/2022]
Abstract
Clinical and animal studies indicate that maternal consumption of ethanol during pregnancy increases alcohol drinking in the offspring. Possible underlying mechanisms may involve orexigenic peptides, which are stimulated by prenatal ethanol exposure and themselves promote drinking. Building on evidence that ethanol stimulates neuroimmune factors such as the chemokine CCL2 that in adult rats is shown to colocalize with the orexigenic peptide, melanin-concentrating hormone (MCH) in the lateral hypothalamus (LH), the present study sought to investigate the possibility that CCL2 or its receptor CCR2 in LH is stimulated by prenatal ethanol exposure, perhaps specifically within MCH neurons. Our paradigm of intraoral administration of ethanol to pregnant rats, at low-to-moderate doses (1 or 3g/kg/day) during peak hypothalamic neurogenesis, caused in adolescent male offspring twofold increase in drinking of and preference for ethanol and reinstatement of ethanol drinking in a two-bottle choice paradigm under an intermittent access schedule. This effect of prenatal ethanol exposure was associated with an increased expression of MCH and density of MCH(+) neurons in LH of preadolescent offspring. Whereas CCL2(+) cells at this age were low in density and unaffected by ethanol, CCR2(+) cells were dense in LH and increased by prenatal ethanol, with a large percentage (83-87%) identified as neurons and found to colocalize MCH. Prenatal ethanol also stimulated the genesis of CCR2(+) and MCH(+) neurons in the embryo, which co-labeled the proliferation marker, BrdU. Ethanol also increased the genesis and density of neurons that co-expressed CCR2 and MCH in LH, with triple-labeled CCR2(+)/MCH(+)/BrdU(+) neurons that were absent in control rats accounting for 35% of newly generated neurons in ethanol-exposed rats. With both the chemokine and MCH systems believed to promote ethanol consumption, this greater density of CCR2(+)/MCH(+) neurons in the LH of preadolescent rats suggests that these systems function together in promoting alcohol drinking during adolescence.
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Affiliation(s)
- G-Q Chang
- Laboratory of Behavioral Neurobiology, The Rockefeller University, New York, NY 10065, USA
| | - O Karatayev
- Laboratory of Behavioral Neurobiology, The Rockefeller University, New York, NY 10065, USA
| | - S F Leibowitz
- Laboratory of Behavioral Neurobiology, The Rockefeller University, New York, NY 10065, USA.
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Perreau-Lenz S, Spanagel R. Clock genes × stress × reward interactions in alcohol and substance use disorders. Alcohol 2015; 49:351-7. [PMID: 25943583 PMCID: PMC4457607 DOI: 10.1016/j.alcohol.2015.04.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 04/13/2015] [Indexed: 12/31/2022]
Abstract
Adverse life events and highly stressful environments have deleterious consequences for mental health. Those environmental factors can potentiate alcohol and drug abuse in vulnerable individuals carrying specific genetic risk factors, hence producing the final risk for alcohol- and substance-use disorders development. The nature of these genes remains to be fully determined, but studies indicate their direct or indirect relation to the stress hypothalamo-pituitary-adrenal (HPA) axis and/or reward systems. Over the past decade, clock genes have been revealed to be key-players in influencing acute and chronic alcohol/drug effects. In parallel, the influence of chronic stress and stressful life events in promoting alcohol and substance use and abuse has been demonstrated. Furthermore, the reciprocal interaction of clock genes with various HPA-axis components, as well as the evidence for an implication of clock genes in stress-induced alcohol abuse, have led to the idea that clock genes, and Period genes in particular, may represent key genetic factors to consider when examining gene × environment interaction in the etiology of addiction. The aim of the present review is to summarize findings linking clock genes, stress, and alcohol and substance abuse, and to propose potential underlying neurobiological mechanisms.
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Affiliation(s)
- Stéphanie Perreau-Lenz
- Institute of Psychopharmacology, Central Institute for Mental Health, Medical Faculty of Mannheim, Heidelberg University, Mannheim, Germany; SRI International, Center for Neuroscience, Biosciences Division, Menlo Park, CA, USA.
| | - Rainer Spanagel
- Institute of Psychopharmacology, Central Institute for Mental Health, Medical Faculty of Mannheim, Heidelberg University, Mannheim, Germany
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22
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Chastain LG, Sarkar DK. Role of microglia in regulation of ethanol neurotoxic action. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2015; 118:81-103. [PMID: 25175862 DOI: 10.1016/b978-0-12-801284-0.00004-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Exposure to alcohol, during development or adulthood, may result in damage to the nervous system, which underlies neurological and cognitive disruptions observed in patients with alcohol-related disorders, including fetal alcohol spectrum disorders (FASDs) and alcohol-use disorders (AUDs). Both clinical and preclinical evidence suggest microglia, the immune cells of the central nervous system, play a key role in modulating alcohol-induced neurotoxicity. Particularly, microglia are implicated in alcohol-induced neuroinflammation and in alcohol-induced increases in oxidative stress, which can lead to neuronal apoptosis. Recent studies also suggest a regenerative role for microglia in reestablishing homeostasis after alcohol exposure. These studies are summarized and reviewed in this chapter with emphasis on relevance to FASD and AUD.
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Affiliation(s)
- Lucy G Chastain
- Endocrinology Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
| | - Dipak K Sarkar
- Endocrinology Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA.
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Stress and opioids: role of opioids in modulating stress-related behavior and effect of stress on morphine conditioned place preference. Neurosci Biobehav Rev 2015; 51:138-50. [PMID: 25636946 DOI: 10.1016/j.neubiorev.2014.12.018] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 12/24/2014] [Accepted: 12/31/2014] [Indexed: 11/21/2022]
Abstract
Research studies have defined the important role of endogenous opioids in modulating stress-associated behavior. The release of β-endorphins in the amygdala in response to stress helps to cope with a stressor by inhibiting the over-activation of HPA axis. Administration of mu opioid agonists reduces the risk of developing post-traumatic stress disorder (PTSD) following a traumatic event by inhibiting fear-related memory consolidation. Similarly, the release of endogenous enkephalin and nociceptin in the basolateral amygdala and the nucleus accumbens tends to produce the anti-stress effects. An increase in dynorphin levels during prolonged exposure to stress may produce learned helplessness, dysphoria and depression. Stress also influences morphine-induced conditioned place preference (CPP) depending upon the intensity and duration of the stressor. Acute stress inhibits morphine CPP, while chronic stress potentiates CPP. The development of dysphoria due to increased dynorphin levels may contribute to chronic stress-induced potentiation of morphine CPP. The activation of ERK/cyclic AMP responsive element-binding (CREB) signaling in the mesocorticolimbic area, glucocorticoid receptors in the basolateral amygdala, and norepinephrine and galanin system in the nucleus accumbens may decrease the acute stress-induced inhibition of morphine CPP. The increase in dopamine levels in the nucleus accumbens and augmentation of GABAergic transmission in the median prefrontal cortex may contribute in potentiating morphine CPP. Stress exposure reinstates the extinct morphine CPP by activating the orexin receptors in the nucleus accumbens, decreasing the oxytocin levels in the lateral septum and amygdala, and altering the GABAergic transmission (activation of GABAA and inactivation of GABAB receptors). The present review describes these varied interactions between opioids and stress along with the possible mechanism.
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Sarkar DK. Fetal alcohol exposure increases susceptibility to carcinogenesis and promotes tumor progression in prostate gland. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 815:389-402. [PMID: 25427920 DOI: 10.1007/978-3-319-09614-8_23] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The idea that exposure to adverse environmental conditions and lifestyle choices during pregnancy can result in fetal programming that underlies disease susceptibility in adulthood is now widely accepted. Fetal alcohol exposed offspring displays many behavioral and physiological abnormalities including neuroendocrine-immune functions, which often carry over into their adult life. Since the neuroendocrine-immune system plays an important role in controlling tumor surveillance, fetal alcohol exposed offspring can be vulnerable to develop cancer. Animal studies have recently showed increased cancer growth and progression in various tissues of fetal alcohol exposed offspring. I will detail in this chapter the recent evidence for increased prostate carcinogenesis in fetal alcohol exposed rats. I will also provide evidence for a role of excessive estrogenization during prostatic development in the increased incidence of prostatic carcinoma in these animals. Furthermore, I will discuss the additional possibility of the involvement of impaired stress regulation and resulting immune incompetence in the increased prostatic neoplasia in the fetal alcohol exposed offspring.
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Affiliation(s)
- Dipak K Sarkar
- Endocrinology Program and Department of Animal Sciences, Rutgers, The State University of New Jersey, 67 Poultry Farm Road, New Brunswick, NJ, 08901, USA,
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25
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Gangisetty O, Bekdash R, Maglakelidze G, Sarkar DK. Fetal alcohol exposure alters proopiomelanocortin gene expression and hypothalamic-pituitary-adrenal axis function via increasing MeCP2 expression in the hypothalamus. PLoS One 2014; 9:e113228. [PMID: 25409090 PMCID: PMC4237387 DOI: 10.1371/journal.pone.0113228] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 10/21/2014] [Indexed: 11/19/2022] Open
Abstract
Proopiomelanocortin (POMC) is a precursor gene of the neuropeptide β-endorphin in the hypothalamus and is known to regulate various physiological functions including stress response. Several recent reports showed that fetal alcohol exposure programs the hypothalamus to produce lower levels of POMC gene transcripts and to elevate the hypothalamic-pituitary-adrenal (HPA) axis response to stressful stimuli. We investigated the role of methyl CpG binding protein (MeCP2) in the effects of prenatal ethanol on POMC gene expression and hypothalamic-pituitary-adrenal (HPA) axis function. Pregnant Sprague Dawley rats were fed between GD 7 and 21 with a liquid diet containing 6.7% alcohol, pair-fed with isocaloric liquid diet, or fed ad libitum with rat chow, and their male offsprings were used at 60 days after birth in this study. Fetal alcohol exposure reduced the level of POMC mRNA, but increased the level of DNA methylation of this gene in the arcuate nucleus (ARC) of the hypothalamus where the POMC neuronal cell bodies are located. Fetal alcohol exposed rats showed a significant increase in MeCP2 protein levels in POMC cells, MeCP2 gene transcript levels as well as increased MeCP2 protein binding on the POMC promoter in the arcuate nucleus. Lentiviral delivery of MeCP2 shRNA into the third ventricle efficiently reduced MeCP2 expression and prevented the effect of prenatal ethanol on POMC gene expression in the arcuate nucleus. MeCP2-shRNA treatment also normalized the prenatal ethanol-induced increase in corticotropin releasing hormone (CRH) gene expression in the hypothalamus and elevated plasma adrenocorticotrophic hormone (ACTH) and corticosterone hormone responses to lipopolysaccharide (LPS) challenge. These results suggest that fetal alcohol programming of POMC gene may involve recruitment of MeCP2 on to the methylated promoter of the POMC gene to suppress POMC transcript levels and contribute to HPA axis dysregulation.
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Affiliation(s)
- Omkaram Gangisetty
- Endocrine Program, Department of Animal Sciences, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Rola Bekdash
- Endocrine Program, Department of Animal Sciences, Rutgers University, New Brunswick, New Jersey, United States of America
| | - George Maglakelidze
- Endocrine Program, Department of Animal Sciences, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Dipak K. Sarkar
- Endocrine Program, Department of Animal Sciences, Rutgers University, New Brunswick, New Jersey, United States of America
- * E-mail:
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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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Agapito MA, Zhang C, Murugan S, Sarkar DK. Fetal alcohol exposure disrupts metabolic signaling in hypothalamic proopiomelanocortin neurons via a circadian mechanism in male mice. Endocrinology 2014; 155:2578-88. [PMID: 24797626 PMCID: PMC4060182 DOI: 10.1210/en.2013-2030] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Early-life ethanol feeding (ELAF) alters the metabolic function of proopiomelanocortin (POMC)-producing neurons and the circadian expression of clock regulatory genes in the hypothalamus. We investigated whether the circadian mechanisms control the action of ELAF on metabolic signaling genes in POMC neurons. Gene expression measurements of Pomc and a selected group of metabolic signaling genes, Stat3, Sirt1, Pgc1-α, and Asb4 in laser-captured microdissected POMC neurons in the hypothalamus of POMC-enhanced green fluorescent protein mice showed circadian oscillations under light/dark and constant darkness conditions. Ethanol programmed these neurons such that the adult expression of Pomc, Stat3, Sirt, and Asb4 gene transcripts became arrhythmic. In addition, ELAF dampened the circadian peak of gene expression of Bmal1, Per1, and Per2 in POMC neurons. We crossed Per2 mutant mice with transgenic POMC-enhanced green fluorescent protein mice to determine the role of circadian mechanism in ELAF-altered metabolic signaling in POMC neurons. We found that ELAF failed to alter arrhythmic expression of most circadian genes, with the exception of the Bmal1 gene and metabolic signaling regulating genes in Per2 mutant mice. Comparison of the ELAF effects on the circadian blood glucose in wild-type and Per2 mutant mice revealed that ELAF dampened the circadian peak of glucose, whereas the Per2 mutation shifted the circadian cycle and prevented the ELAF dampening of the glucose peak. These data suggest the possibility that the Per2 gene mutation may regulate the ethanol actions on Pomc and the metabolic signaling genes in POMC neurons in the hypothalamus by blocking circadian mechanisms.
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Affiliation(s)
- Maria A Agapito
- Endocrine Program (M.A.A., C.Z., S.M., D.K.S.), Graduate Program in Neuroscience (M.A.A.), Graduate Program in Endocrinology and Animal Biosciences (C.Z.), and Department of Animal Sciences (S.M., D.K.S.), Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901
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Mead EA, Sarkar DK. Fetal alcohol spectrum disorders and their transmission through genetic and epigenetic mechanisms. Front Genet 2014; 5:154. [PMID: 24917878 PMCID: PMC4040491 DOI: 10.3389/fgene.2014.00154] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 05/09/2014] [Indexed: 12/20/2022] Open
Abstract
Fetal alcohol spectrum disorders (FASD) are a group of related conditions that arise from prenatal exposure to maternal consumption of the teratogen, ethanol. It has been estimated that roughly 1% of children in the US suffer from FASD (Sampson etal., 1997), though in some world populations, such as inhabitants of some poorer regions of South Africa, the rate can climb to as high as 20% (May etal., 2013). FASD are the largest cause of mental retardation in U.S. neonates, and ironically, are entirely preventable. FASD have been linked to major changes in the hypothalamic-pituitary-adrenal (HPA) axis, resulting in lifelong impairments through mental disorders, retardation, and sensitivity to stress. FASD are linked to an impaired immune system which consequently leads to an elevated risk of cancer and other diseases. FASD arise from a complex interplay of genetic and epigenetic factors. Here, we review current literature on the topic to tease apart what is known in these areas particularly emphasizing HPA axis dysfunction and how this ties into new studies of transgenerational inheritance in FASD.
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Affiliation(s)
- Edward A Mead
- Rutgers Endocrine Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Dipak K Sarkar
- Rutgers Endocrine Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
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Rachdaoui N, Sarkar DK. Transgenerational epigenetics and brain disorders. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2014; 115:51-73. [PMID: 25131542 DOI: 10.1016/b978-0-12-801311-3.00002-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Neurobehavioral and psychiatric disorders are complex diseases with a strong heritable component; however, to date, genome-wide association studies failed to identify the genetic loci involved in the etiology of these brain disorders. Recently, transgenerational epigenetic inheritance has emerged as an important factor playing a pivotal role in the inheritance of brain disorders. This field of research provides evidence that environmentally induced epigenetic changes in the germline during embryonic development can be transmitted for multiple generations and may contribute to the etiology of brain disease heritability. In this review, we discuss some of the most recent findings on transgenerational epigenetic inheritance. We particularly discuss the findings on the epigenetic mechanisms involved in the heritability of alcohol-induced neurobehavioral disorders such as fetal alcohol spectrum disorders.
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Affiliation(s)
- Nadia Rachdaoui
- Rutgers Endocrine Research Program, Department of Animal Sciences, Rutgers University, New Brunswick, New Jersey, USA
| | - Dipak K Sarkar
- Rutgers Endocrine Research Program, Department of Animal Sciences, Rutgers University, New Brunswick, New Jersey, USA.
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Clave S, Joya X, Salat-Batlle J, Garcia-Algar O, Vall O. Ethanol cytotoxic effect on trophoblast cells. Toxicol Lett 2013; 225:216-21. [PMID: 24374569 DOI: 10.1016/j.toxlet.2013.12.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 12/18/2013] [Accepted: 12/19/2013] [Indexed: 01/13/2023]
Abstract
Prenatal ethanol exposure may cause both, altered fetal neurodevelopment and impaired placental function. These disturbances can lead to growth retardation, which is one of the most prevalent features in Fetal Alcohol Syndrome (FAS). It is not known whether there is a specific pattern of cytotoxicity caused by ethanol that can be extrapolated to other cell types. The aim of this study was to determine the cytotoxic effects caused by sustained exposure of trophoblast cells to ethanol. The cytotoxic effect of sustained exposure to standard doses of ethanol on an in vitro human trophoblast cell line, JEG3, was examined. Viable cell count by exclusion method, total protein concentration, lactate dehydrogenase (LDH) activity and activation of apoptotic markers (P-H2AX, caspase-3 and PARP-1) were determined. Sustained exposure to ethanol decreased viable cell count and total protein concentration. LDH activity did not increased in exposed cells but apoptotic markers were detected. In addition, there was a dose-dependent relationship between ethanol concentration and apoptotic pathways activation. Sustained ethanol exposure causes cellular cytotoxicity by apoptotic pathways induction as a result of DNA damage. This apoptotic induction may partially explain the altered function of placental cells and the damage previously detected in other tissues.
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Affiliation(s)
- S Clave
- Unitat de Recerca Infància i Entorn (URIE), Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), PRBB, C/ Dr. Aiguader 88, 08003 Barcelona, Spain; Red de Salud Materno Infantil y del Desarrollo (SAMID), Programa RETIC, Instituto Carlos III, C/ Sinesio Delgado 4, 28029 Madrid, Spain
| | - X Joya
- Unitat de Recerca Infància i Entorn (URIE), Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), PRBB, C/ Dr. Aiguader 88, 08003 Barcelona, Spain; Red de Salud Materno Infantil y del Desarrollo (SAMID), Programa RETIC, Instituto Carlos III, C/ Sinesio Delgado 4, 28029 Madrid, Spain
| | - J Salat-Batlle
- Unitat de Recerca Infància i Entorn (URIE), Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), PRBB, C/ Dr. Aiguader 88, 08003 Barcelona, Spain; Red de Salud Materno Infantil y del Desarrollo (SAMID), Programa RETIC, Instituto Carlos III, C/ Sinesio Delgado 4, 28029 Madrid, Spain
| | - O Garcia-Algar
- Unitat de Recerca Infància i Entorn (URIE), Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), PRBB, C/ Dr. Aiguader 88, 08003 Barcelona, Spain; Red de Salud Materno Infantil y del Desarrollo (SAMID), Programa RETIC, Instituto Carlos III, C/ Sinesio Delgado 4, 28029 Madrid, Spain; Departament de Pediatria, Obstetricia i Ginecologia, i Medicina Preventiva, Universitat Autònoma de Barcelona (UAB), Campus M, 08193 Bellaterra, Spain.
| | - O Vall
- Unitat de Recerca Infància i Entorn (URIE), Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), PRBB, C/ Dr. Aiguader 88, 08003 Barcelona, Spain; Red de Salud Materno Infantil y del Desarrollo (SAMID), Programa RETIC, Instituto Carlos III, C/ Sinesio Delgado 4, 28029 Madrid, Spain; Departament de Pediatria, Obstetricia i Ginecologia, i Medicina Preventiva, Universitat Autònoma de Barcelona (UAB), Campus M, 08193 Bellaterra, Spain
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Abstract
Chronic consumption of a large amount of alcohol disrupts the communication between nervous, endocrine, and immune system and causes hormonal disturbances that lead to profound and serious consequences at physiologic and behavioral levels. These alcohol-induced hormonal dysregulations affect the entire body and can result in various disorders such as stress abnormalities, reproductive deficits, body growth defect, thyroid problems, immune dysfunction, cancers, bone disease, and psychological and behavioral disorders. This review summarizes the findings from human and animal studies that provide consistent evidence on the various effects of alcohol abuse on the endocrine system.
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Affiliation(s)
- Nadia Rachdaoui
- Nadia Rachdaoui, Ph.D., Rutgers Endocrine Research Program. Department of Animal Sciences Rutgers University, 67 Poultry Farm Lane, New Brunswick, NJ 08901,
| | - Dipak K. Sarkar
- Dipak K. Sarkar, Ph.D., D. Phil., Rutgers Endocrine Research Program. Department of Animal Sciences, Rutgers University, 67 Poultry Farm Lane, New Brunswick, NJ 08901,
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Boyadjieva NI, Sarkar DK. Cyclic adenosine monophosphate and brain-derived neurotrophic factor decreased oxidative stress and apoptosis in developing hypothalamic neuronal cells: role of microglia. Alcohol Clin Exp Res 2013; 37:1370-9. [PMID: 23550806 DOI: 10.1111/acer.12104] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2012] [Accepted: 01/12/2013] [Indexed: 01/25/2023]
Abstract
BACKGROUND We have previously shown that ethanol (EtOH) increases cellular apoptosis to developing neurons via the effects on oxidative stress of neurons directly and via increasing production of microglia-derived factors. To study further the mechanism of EtOH action on neuronal apoptosis, we determined the effects of 2 well-known PKA activators, dibutyryl cAMP (dbcAMP) and brain-derived neurotrophic factor (BDNF), on EtOH-activated oxidative stress and apoptotic processes in the hypothalamic neurons in the presence and absence of microglial cells' influence. METHODS In enriched neuronal cells from fetal rat hypothalami treated with EtOH or with conditioned medium from EtOH-treated microglia, we measured cellular apoptosis by the free nucleosome assay and the levels of cAMP, BDNF, O²⁻, reactive oxygen species (ROS), nitrite, glutathione (GSH), and catalase following treatment with EtOH or EtOH-treated microglial culture conditioned medium. Additionally, we tested the effectiveness of dbcAMP and BDNF in preventing EtOH or EtOH-treated microglial conditioned medium on cellular apoptosis and oxidative stress in enriched hypothalamic neuronal cell in primary cultures. RESULTS Neuronal cell cultures following treatment with EtOH or EtOH-activated microglial conditioned medium showed decreased production levels of cAMP and BDNF. EtOH also increased apoptotic death as well as oxidative status, as demonstrated by higher cellular levels of oxidants but lower levels of antioxidants, in neuronal cells. These effects of EtOH on oxidative stress and cell death were enhanced by the presence of microglia. Treatment with BDNF or dbcAMP decreased EtOH or EtOH-activated microglial conditioned medium-induced changes in the levels of intracellular free radicals, ROS and O²⁻, nitrite, GSH, and catalase. CONCLUSIONS These data support the possibility that EtOH by acting directly and via increasing the production of microglial-derived factors reduces cellular levels of cAMP and BDNF to increase cellular oxidative status and apoptosis in hypothalamic neuronal cells in primary cultures.
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Affiliation(s)
- Nadka I Boyadjieva
- Endocrine Program, Department of Animal Sciences, Graduate Program of Neuroscience, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
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Barfield ET, Moser VA, Hand A, Grisel JE. β-endorphin modulates the effect of stress on novelty-suppressed feeding. Front Behav Neurosci 2013; 7:19. [PMID: 23503677 PMCID: PMC3596765 DOI: 10.3389/fnbeh.2013.00019] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 02/26/2013] [Indexed: 11/19/2022] Open
Abstract
Although stress is implicated in the pathophysiology of mood and anxiety disorders, not all individuals who suffer stressful life events develop psychopathology. Differential susceptibility to stress may be influenced by genetically mediated differences in hypothalamic-pituitary-adrenal (HPA) axis activity and moderation of the stress response by the opioid peptide β-endorphin (β-E). The present study investigated genetic contributions to coping behavior by examining anxious behavior of transgenic mice with varying capacities to synthesize β-E [B6.129S2-Pomctm1Low/J; regulated by insertion of a premature stop codon into one or both copies of the proopiomelanocortin (POMC) gene], both under normal conditions and following 3 min of forced swim (FS). Ten minutes after this stress exposure or a control manipulation, acutely food-deprived female and male transgenic mice were subjected to a novelty-suppressed feeding (NSF) test, during which their interaction with an almond slice located in the center of an open field box was measured. There was an interaction between genotype and stress for latency to approach the almond and whether or not the almond was approached, such that mice with low or absent β-E displayed a stronger aversion to novelty-feeding after stress exposure than did mice with normal levels. These data provide evidence for a moderating effect of β-E on the behavioral response to stress. Genotypic differences in anxious behavior emerged when mice were stressed prior to behavioral assessment, suggesting that β-E plays a role in coping behavior. These findings indicate that genetic variability in sensitivity of the β-E system to stress may contribute, at least in part, to heritable differences in stress reactivity as well as vulnerability to stress-related psychopathology.
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Bekdash RA, Zhang C, Sarkar DK. Gestational choline supplementation normalized fetal alcohol-induced alterations in histone modifications, DNA methylation, and proopiomelanocortin (POMC) gene expression in β-endorphin-producing POMC neurons of the hypothalamus. Alcohol Clin Exp Res 2013; 37:1133-42. [PMID: 23413810 DOI: 10.1111/acer.12082] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Accepted: 11/08/2012] [Indexed: 02/03/2023]
Abstract
BACKGROUND Prenatal exposure to ethanol (EtOH) reduces the expression of hypothalamic proopiomelanocortin (POMC) gene, known to control various physiological functions including the organismal stress response. In this study, we determined whether the changes in POMC neuronal functions are associated with altered expressions of histone-modifying and DNA-methylating enzymes in POMC-producing neurons, because these enzymes are known to be involved in regulation of gene expression. In addition, we tested whether gestational choline supplementation prevents the adverse effects of EtOH on these neurons. METHODS Pregnant rat dams were fed with alcohol-containing liquid diet or control diet during gestational days 7 and 21 with or without choline, and their male offspring rats were used during the adult period. Using double-immunohistochemistry, real-time reverse transcription polymerase chain reaction (RT-PCR) and methylation-specific RT-PCR, we determined protein and mRNA levels of histone-modifying and DNA-methylating enzymes and the changes in POMC gene methylation and expression in the hypothalamus of adult male offspring rats. Additionally, we measured the basal- and lipopolysaccharide (LPS)-induced corticosterone levels in plasma by enzyme-linked immunosorbent assay. RESULTS Prenatal EtOH treatment suppressed hypothalamic levels of protein and mRNA of histone activation marks (H3K4me3, Set7/9, acetylated H3K9, phosphorylated H3S10), and increased the repressive marks (H3K9me2, G9a, Setdb1), DNA-methylating enzyme (Dnmt1), and the methyl-CpG-binding protein (MeCP2). The treatment also elevated the level of POMC gene methylation, while it reduced levels of POMC mRNA and β-EP and elevated corticosterone response to LPS. Gestational choline normalized the EtOH-altered protein and the mRNA levels of H3K4me3, Set7/9, H3K9me2, G9a, Setdb1, Dnmt1, and MeCP2. It also normalizes the changes in POMC gene methylation and gene expression, β-EP production, and the corticosterone response to LPS. CONCLUSIONS These data suggest that prenatal EtOH modulates histone and DNA methylation in POMC neurons that may be resulting in hypermethylation of POMC gene and reduction in POMC gene expression. Gestational choline supplementation prevents the adverse effects of EtOH on these neurons.
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Affiliation(s)
- Rola A Bekdash
- Endocrine Program, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
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Sharma A. Transgenerational epigenetic inheritance: focus on soma to germline information transfer. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2012; 113:439-46. [PMID: 23257323 DOI: 10.1016/j.pbiomolbio.2012.12.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 11/30/2012] [Accepted: 12/06/2012] [Indexed: 01/29/2023]
Abstract
In trangenerational epigenetic inheritance, phenotypic information not encoded in DNA sequence is transmitted across generations. In germline-dependent mode, memory of environmental exposure in parental generation is transmitted through gametes, leading to appearance of phenotypes in the unexposed future generations. The memory is considered to be encoded in epigenetic factors like DNA methylation, histone modifications and regulatory RNAs. Environmental exposure may cause epigenetic modifications in the germline either directly or indirectly through primarily affecting the soma. The latter possibility is most intriguing because it contradicts the established dogma that hereditary information flows only from germline to soma, not in reverse. As such, identification of the factor(s) mediating soma to germline information transfer in transgenerational epigenetic inheritance would be pathbreaking. Regulatory RNAs and hormone have previously been implicated or proposed to play a role in soma to germline communication in epigenetic inheritance. This review examines the recent examples of gametogenic transgenerational inheritance in plants and animals in order to assess if evidence of regulatory RNAs and hormones as mediators of information transfer is supported. Overall, direct evidence for both mobile regulatory RNAs and hormones is found to exist in plants. In animals, although involvement of mobile RNAs seems imminent, direct evidence of RNA-mediated soma to germline information transfer in transgenerational epigenetic inheritance is yet to be obtained. Direct evidence is also lacking for hormones in animals. However, detailed examination of recently reported examples of transgenerational inheritance reveals circumstantial evidence supporting a role of hormones in information transmission.
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Affiliation(s)
- Abhay Sharma
- CSIR-Institute of Genomics and Integrative Biology, Council of Scientific and Industrial Research, Delhi University Campus, Mall Road, Delhi 110007, India.
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Wong CCP, Schumann G. Integration of the circadian and stress systems: influence of neuropeptides and implications for alcohol consumption. J Neural Transm (Vienna) 2012; 119:1111-20. [PMID: 22648536 DOI: 10.1007/s00702-012-0829-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 05/10/2012] [Indexed: 12/16/2022]
Abstract
Disruptions in circadian rhythm and stress reactivity are associated with risks of developing neuropsychiatric disorders. The circadian system is organised in a hierarchical manner, whereby the master clock is located at the suprachiasmatic nucleus, a highly conserved brain region that coordinates the oscillations of peripheral clocks. Exposure to psychological stress leads to activation of the hypothalamic-pituitary-adrenal axis. There is growing evidence supporting the interactions between the circadian and stress systems. Anatomically, the circadian and stress signals converge at the paraventricular nucleus (PVN) in the hypothalamus. Genes that are involved in the operation of the circadian and stress systems, including Clock, Period and CRH are expressed in the PVN. In addition, several neuropeptides, including arginin-vasopressin, vasoactive intestinal polypeptide, pituitary adenylate cyclase-activating polypeptide and the neurotransmitter gamma-aminobutyric acid, are present in the PVN. In this review, we will discuss the interaction of circadian genes and stress-response genes at the molecular, neurotransmission and behavioural levels. We will place particular emphasis on the role of neuropeptides in mediating this interaction.
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Affiliation(s)
- Cybele C P Wong
- MRC-SGDP Centre, Institute of Psychiatry, King's College London, 16 De Crespigny Park, London SE5 8AF, UK.
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Govorko D, Bekdash RA, Zhang C, Sarkar DK. Male germline transmits fetal alcohol adverse effect on hypothalamic proopiomelanocortin gene across generations. Biol Psychiatry 2012; 72:378-88. [PMID: 22622000 PMCID: PMC3414692 DOI: 10.1016/j.biopsych.2012.04.006] [Citation(s) in RCA: 165] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Revised: 03/16/2012] [Accepted: 04/05/2012] [Indexed: 10/28/2022]
Abstract
BACKGROUND Neurons containing proopiomelanocortin (POMC)-derived peptides, known to control stress axis, metabolic, and immune functions, have a lower function in patients with a family history of alcoholism, raising the possibility that alcohol effects on the POMC system may transmit through generations. Here we describe epigenetic modifications of Pomc gene that transmit through generation via male germline and may be critically involved in alcoholism-inherited diseases. METHODS Whether an epigenetic mechanism is involved in causing a Pomc expression deficit in fetal alcohol-exposed rats is studied by determining Pomc gene methylation, expression, and functional abnormalities and their normalization following suppression of DNA methylation or histone acetylation. Additionally, transgenerational studies were conducted to evaluate the germline-transmitted effect of alcohol. RESULTS Fetal alcohol-exposed male and female rat offspring showed a significant deficit in POMC neuronal functions. Associated with this was an increased methylation status of several CpG dinucleotides in the proximal part of the Pomc promoter region and altered level of histone-modifying proteins and DNA methyltransferases levels in POMC neurons. Suppression of histone deacetylation and DNA methylation normalized Pomc expression and functional abnormalities. Fetal alcohol-induced Pomc gene methylation, expression, and functional defects persisted in the F2 and F3 male but not in female germline. Additionally, the hypermethylated Pomc gene was detected in sperm of fetal alcohol-exposed F1 offspring that was transmitted through F3 generation via male germline. CONCLUSIONS Trangenerational epigenetic studies should spur new insight into the biological mechanisms that influence the sex-dependent difference in genetic risk of alcoholism-inherited diseases.
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The relationship between naloxone-induced cortisol and mu opioid receptor availability in mesolimbic structures is disrupted in alcohol dependent subjects. Alcohol 2012; 46:511-7. [PMID: 22717196 DOI: 10.1016/j.alcohol.2012.04.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 04/19/2012] [Accepted: 04/20/2012] [Indexed: 11/21/2022]
Abstract
The mu opioid receptor system is altered in alcohol dependent (AD) subjects. Cortisol responses to opioid receptor antagonists are assumed to impart information about opioid receptor activity. In the present study we examined naloxone-induced cortisol responses in 18 healthy control (HC) and 25 recently detoxified AD subjects and then correlated the cortisol response with mu opioid receptor availability across 15 brain regions using positron emission tomography (PET) and the mu opioid receptor selective ligand [(11)C] Carfentanil (CFN). On average the AD subjects required twice the dose of naloxone to induce a peak cortisol response compared to the HC subjects. Using the rising slope of the cortisol curve (placebo to peak) as a metric we then went on to examine the relationship between cortisol responses to naloxone and [(11)C]CFN BP(ND). There were significant negative relationships between cortisol and [(11)C]CFN binding potential (BP(ND)) in multiple brain regions of HC subjects. However, cortisol responses did not correlate with [(11)C]CFN BP(ND) across any brain region in AD subjects. In summary, naloxone imparts information about individual differences in mu opioid receptor availability throughout the mesolimbic system in healthy individuals. However pathways governing the relationship between naloxone-induced cortisol and mu opioid receptor availability are disrupted during early abstinence in AD subjects.
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Kane CJM, Phelan KD, Drew PD. Neuroimmune mechanisms in fetal alcohol spectrum disorder. Dev Neurobiol 2012; 72:1302-16. [PMID: 22623427 DOI: 10.1002/dneu.22035] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 05/15/2012] [Indexed: 12/24/2022]
Abstract
Fetal alcohol spectrum disorder (FASD) is a major health concern worldwide and results from maternal consumption of alcohol during pregnancy. It produces tremendous individual, social, and economic losses. This review will first summarize the structural, functional, and behavior changes seen in FASD. The development of the neuroimmune system will be then be described with particular emphasis on the role of microglial cells in the normal regulation of homeostatic function in the central nervous system (CNS) including synaptic transmission. The impact of alcohol on the neuroimmune system in the developing CNS will be discussed in the context of several key immune molecules and signaling pathways involved in neuroimmune mechanisms that contribute to FASD. This review concludes with a summary of the development of early therapeutic approaches utilizing immunosuppressive drugs to target alcohol-induced pathologies. The significant role played by neuroimmune mechanisms in alcohol addiction and pathology provides a focus for future research aimed at understanding and treating the consequences of FASD.
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Affiliation(s)
- Cynthia J M Kane
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA.
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Dempsey S, Grisel JE. Locomotor sensitization to EtOH: contribution of β-Endorphin. Front Mol Neurosci 2012; 5:87. [PMID: 22952458 PMCID: PMC3430006 DOI: 10.3389/fnmol.2012.00087] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Accepted: 08/02/2012] [Indexed: 01/21/2023] Open
Abstract
Alcohol use disorders, like all drug addictions, involve a constellation of adaptive changes throughout the brain. Neural activity underlying changes in the rewarding properties of alcohol reflect changes in dopamine transmission in mesolimbic and nigrostriatal pathways and these effects are modulated by endogenous opioids such as β-Endorphin. In order to study the role of β-Endorphin in the development of locomotor sensitization to repeated EtOH exposure, we tested transgenic mice that vary in their capacity to synthesize this peptide as a result of constitutive modification of the Pomc gene. Our results indicate that mice deficient in β-Endorphin show attenuated locomotor activation following an acute injection of EtOH (2.0 g/kg) and, in contrast to wildtype mice, fail to demonstrate locomotor sensitization after 12 days of repeated EtOH injections. These data support the idea that β-Endorphin modulates the locomotor effects of EtOH and contributes to the neuroadaptive changes associated with chronic use.
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Agapito MA, Barreira JC, Logan RW, Sarkar DK. Evidence for possible period 2 gene mediation of the effects of alcohol exposure during the postnatal period on genes associated with maintaining metabolic signaling in the mouse hypothalamus. Alcohol Clin Exp Res 2012; 37:263-9. [PMID: 22823489 DOI: 10.1111/j.1530-0277.2012.01871.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 05/04/2012] [Indexed: 01/24/2023]
Abstract
BACKGROUND Animals exposed to alcohol during the developmental period develop circadian disturbances and metabolic problems that often persist during their adult period. In order to study whether alcohol and the circadian clock interact to alter metabolic signaling in the hypothalamus, we determined whether postnatal alcohol feeding in mice permanently alters metabolic sensing in the hypothalamus. Furthermore, we evaluated whether the effect of circadian disruption via Period 2 (Per2) gene mutation prevents alcohol's effects on metabolic signaling in the hypothalamus. METHODS Per2 mutant and wild-type male and female mice of the same genetic background were given a milk formula containing ethanol (EtOH; 11.34% vol/vol) from postnatal day (PD) 2 to 7 and used for gene expression and peptide level determinations in the hypothalamus at PD7 and PD90. RESULTS We report here that postnatal alcohol feeding reduces the expression of proopiomelanocortin (Pomc) gene and production of β-endorphin and α-melanocyte stimulating hormone (α-MSH) in the hypothalamus that persists into adulthood. In addition, expressions of metabolic sensing genes in the hypothalamus were also reduced as a consequence of postnatal alcohol exposure. These effects were not sex-specific and were observed in both males and females. Mice carrying a mutation of the Per2 gene did not show any reductions in hypothalamic levels of Pomc and metabolic genes and β-endorphin and α-MSH peptides following alcohol exposure. CONCLUSIONS These data suggest that early-life exposure to alcohol alters metabolic sensing to the hypothalamus possibly via regulating Per2 gene and/or the cellular circadian clock mechanism.
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Affiliation(s)
- Maria A Agapito
- Endocrine Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
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Boyadjieva NI, Sarkar DK. Microglia play a role in ethanol-induced oxidative stress and apoptosis in developing hypothalamic neurons. Alcohol Clin Exp Res 2012; 37:252-62. [PMID: 22823548 DOI: 10.1111/j.1530-0277.2012.01889.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Accepted: 05/03/2012] [Indexed: 11/26/2022]
Abstract
BACKGROUND Animals exposed to alcohol during the developmental period develop many physiological and behavioral problems because of neuronal loss in various brain areas including the hypothalamus. Because alcohol exposure is known to induce oxidative stress in developing neurons, we tested whether hypothalamic cells from the fetal brain exposed to ethanol (EtOH) may alter the cell-cell communication between neurons and microglia, thereby leading to increased oxidative stress and the activation of apoptotic processes in the neuronal population in the hypothalamus. METHODS Using enriched neuronal and microglial cells from fetal rat hypothalami, we measured cellular levels of various oxidants (O2 -, reactive oxygen species, nitrite), antioxidants (glutathione [GSH]), antioxidative enzymes (glutathione peroxidase [GSH-Px], catalase, superoxide dismutase) and apoptotic death in neurons in the presence and absence of EtOH or EtOH-treated microglial culture medium. Additionally, we tested the effectiveness of antioxidative agents in preventing EtOH or EtOH-treated microglial conditioned medium actions on oxidative stress and apoptosis in neuronal cell cultures. RESULTS Neuronal cell cultures showed increased oxidative stress, as demonstrated by higher cellular levels of oxidants but lower levels of antioxidant and antioxidative enzymes, as well as, increased apoptotic death following treatment with EtOH. These effects of EtOH on oxidative stress and cell death were enhanced by the presence of microglia. Antioxidative agents protected developing hypothalamic neurons from oxidative stress and cellular apoptosis which is caused by EtOH or EtOH-treated microglial culture medium. CONCLUSIONS These data suggest that exposure of developing hypothalamic neurons to EtOH increases cellular apoptosis via the effects on oxidative stress of neurons directly and via increasing production of microglial-derived factor(s).
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Affiliation(s)
- Nadka I Boyadjieva
- Endocrine Program, Department of Animal Sciences (NIB, DKS), Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
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Sarkar DK, Sengupta A, Zhang C, Boyadjieva N, Murugan S. Opiate antagonist prevents μ- and δ-opiate receptor dimerization to facilitate ability of agonist to control ethanol-altered natural killer cell functions and mammary tumor growth. J Biol Chem 2012; 287:16734-47. [PMID: 22451667 DOI: 10.1074/jbc.m112.347583] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In the natural killer (NK) cells, δ-opiate receptor (DOR) and μ-opioid receptor (MOR) interact in a feedback manner to regulate cytolytic function with an unknown mechanism. Using RNK16 cells, a rat NK cell line, we show that MOR and DOR monomer and dimer proteins existed in these cells and that chronic treatment with a receptor antagonist reduced protein levels of the targeted receptor but increased levels of opposing receptor monomer and homodimer. The opposing receptor-enhancing effects of MOR and DOR antagonists were abolished following receptor gene knockdown by siRNA. Ethanol treatment increased MOR and DOR heterodimers while it decreased the cellular levels of MOR and DOR monomers and homodimers. The opioid receptor homodimerization was associated with an increased receptor binding, and heterodimerization was associated with a decreased receptor binding and the production of cytotoxic factors. Similarly, in vivo, opioid receptor dimerization, ligand binding of receptors, and cell function in immune cells were promoted by chronic treatment with an opiate antagonist but suppressed by chronic ethanol feeding. Additionally, a combined treatment of an MOR antagonist and a DOR agonist was able to reverse the immune suppressive effect of ethanol and reduce the growth and progression of mammary tumors in rats. These data identify a role of receptor dimerization in the mechanism of DOR and MOR feedback interaction in NK cells, and they further elucidate the potential for the use of a combined opioid antagonist and agonist therapy for the treatment of immune incompetence and cancer and alcohol-related diseases.
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Affiliation(s)
- Dipak K Sarkar
- Endocrine Program, Department of Animal Sciences, Rutgers, State University of New Jersey, New Brunswick, New Jersey 08901, USA
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Sarkar DK, Zhang C, Murugan S, Dokur M, Boyadjieva NI, Ortigüela M, Reuhl KR, Mojtehedzadeh S. Transplantation of β-endorphin neurons into the hypothalamus promotes immune function and restricts the growth and metastasis of mammary carcinoma. Cancer Res 2011; 71:6282-91. [PMID: 21835894 DOI: 10.1158/0008-5472.can-11-1610] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Neurobehavioral stress has been shown to promote tumor growth and progression and dampen the immune system. In this study, we investigated whether inhibiting stress hormone production could inhibit the development of mammary carcinoma and metastasis in a rat model of breast carcinogenesis. To enhance β-endorphin (BEP), the endogenous opioid polypeptide that boosts immune activity and decreases stress, we generated BEP neurons by in vitro differentiation from fetal neuronal stem cells and transplanted them into the hypothalami of rats subjected to breast carcinogenesis. BEP-transplanted rats displayed a reduction in mammary tumor incidence, growth, malignancy rate, and metastasis compared with cortical cells-transplanted rats. BEP neuron transplants also reduced inflammation and epithelial to mesenchymal transition in the tumor tissues. In addition, BEP neuron transplants increased peripheral natural killer (NK) cell and macrophage activities, elevated plasma levels of antiinflammatory cytokines, and reduced plasma levels of inflammatory cytokines. Antimetastatic effects along with stimulation of NK cells and macrophages could be reversed by treatment with the opiate antagonist naloxone, the β-receptor agonist metaproterenol, or the nicotine acetylcholine receptor antagonist methyllycaconitine. Together, our findings establish a protective role for BEP against the growth and metastasis of mammary tumor cells by altering autonomic nervous system activities that enhance innate immune function.
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Affiliation(s)
- Dipak K Sarkar
- Rutgers Endocrine Program, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA.
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Laalaoui A, Fèvre-Montange M, Ahboucha S, Gamrani H. Proopiomelanocortin in the arcuate nucleus of the rodent Meriones shawi: effects of dehydration. Acta Histochem 2011; 113:369-74. [PMID: 20447683 DOI: 10.1016/j.acthis.2010.01.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2009] [Revised: 01/20/2010] [Accepted: 01/21/2010] [Indexed: 11/24/2022]
Abstract
Proopiomelanocortin (POMC) is a 36kDa glycoprotein implicated in homeostatic balance. We used in situ hybridization histochemistry coupled with quantitative autoradiography to determine the anatomical distribution of POMC mRNA-expressing neurons in the arcuate nucleus (AN) and to examine the effects of prolonged dehydration on POMC gene expression in a semi-desert rodent, Meriones shawi (Shaw's Jird). In the hypothalamus of control animals, POMC mRNA-expressing neurons were exclusively localized in the AN and they showed a differential distribution and density along its rostro-caudal subdivisions. In dehydrated animals, water deprivation caused a decrease in POMC mRNA labeling in the AN. These results suggest that dehydration stress can induce negative regulation of POMC gene expression in this species. A comparative study of weight variation between control and dehydrated animals showed a weight loss followed by stabilization of weight during prolonged dehydration.
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Boyadjieva NI, Sarkar DK. Role of microglia in ethanol's apoptotic action on hypothalamic neuronal cells in primary cultures. Alcohol Clin Exp Res 2011; 34:1835-42. [PMID: 20662807 DOI: 10.1111/j.1530-0277.2010.01271.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Microglia are the major inflammatory cells in the central nervous system and play a role in brain injuries as well as brain diseases. In this study, we determined the role of microglia in ethanol's apoptotic action on neuronal cells obtained from the mediobasal hypothalamus and maintained in primary cultures. We also tested the effect of cAMP, a signaling molecule critically involved in hypothalamic neuronal survival, on microglia-mediated ethanol's neurotoxic action. METHODS Ethanol's neurotoxic action was determined on enriched fetal mediobasal hypothalamic neuronal cells with or without microglia cells or ethanol-activated microglia-conditioned media. Ethanol's apoptotic action was determined using nucleosome assay. Microglia activation was determined using OX6 histochemistry and by measuring inflammatory cytokines secretion from microglia in cultures using enzyme-linked immunosorbent assay (ELISA). An immunoneutralization study was conducted to identify the role of a cytokine involved in ethanol's apoptotic action. RESULTS We show here that ethanol at a dose range of 50 and 100 mM induces neuronal death by an apoptotic process. Ethanol's ability to induce an apoptotic death of neurons is increased by the presence of ethanol-activated microglia-conditioned media. In the presence of ethanol, microglia showed elevated secretion of various inflammatory cytokines, of which TNF-α shows significant apoptotic action on mediobasal hypothalamic neuronal cells. Ethanol's neurotoxic action was completely prevented by cAMP. The cell-signaling molecule also prevented ethanol-activated microglial production of TNF-α. Immunoneutralization of TNF-α prevented the microglia-derived media's ability to induce neuronal death. CONCLUSIONS These results suggest that ethanol's apoptotic action on hypothalamic neuronal cells might be mediated via microglia, possibly via increased production of TNF-α. Furthermore, cAMP reduces TNF-α production from microglia to prevent ethanol's neurotoxic action.
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Affiliation(s)
- Nadka I Boyadjieva
- Endocrine Program, Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, USA
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Agapito M, Mian N, Boyadjieva NI, Sarkar DK. Period 2 gene deletion abolishes beta-endorphin neuronal response to ethanol. Alcohol Clin Exp Res 2010; 34:1613-8. [PMID: 20586752 DOI: 10.1111/j.1530-0277.2010.01246.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND Ethanol exposure during early life has been shown to permanently alter the circadian expression of clock regulatory genes and the beta-endorphin precursor proopiomelanocortin (POMC) gene in the hypothalamus. Ethanol also alters the stress- and immune-regulatory functions of beta-endorphin neurons in laboratory rodents. Our aim was to determine whether the circadian clock regulatory Per2 gene modulates the action of ethanol on beta-endorphin neurons in mice. METHODS Per2 mutant (mPer2(Brdml)) and wild type (C57BL/6J) mice were used to determine the effect of Per2 mutation on ethanol-regulated beta-endorphin neuronal activity during neonatal period using an in vitro mediobasal hypothalamic (MBH) cell culture model and an in vivo milk formula feeding animal model. The beta-endorphin neuronal activity following acute and chronic ethanol treatments was evaluated by measuring the peptide released from cultured cells or peptide levels in the MBH tissues, using enzyme-linked immunosorbent assay (ELISA). RESULTS Per2 mutant mice showed a higher basal level of beta-endorphin release from cultured MBH cells and a moderate increase in the peptide content in the MBH in comparison with control mice. However, unlike wild type mice, Per2 mutant mice showed no stimulatory or inhibitory beta-endorphin-secretory responses to acute and chronic ethanol challenges in vitro. Furthermore, Per2 mutant mice, but not wild type mice, failed to show the stimulatory and inhibitory responses of MBH beta-endorphin levels to acute and chronic ethanol challenges in vivo. CONCLUSIONS These results suggest for the first time that the Per2 gene may be critically involved in regulating beta-endorphin neuronal function. Furthermore, the data revealed an involvement of the Per2 gene in regulating beta-endorphin neuronal responses to ethanol.
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Affiliation(s)
- Maria Agapito
- Endocrine Program, Department of Animal Sciences, Graduate Program of Neuroscience, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, USA
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Barfield ET, Barry SM, Hodgin HB, Thompson BM, Allen SS, Grisel JE. Beta-endorphin mediates behavioral despair and the effect of ethanol on the tail suspension test in mice. Alcohol Clin Exp Res 2010; 34:1066-72. [PMID: 20384608 DOI: 10.1111/j.1530-0277.2010.01182.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND The opioid peptide beta-endorphin (beta-E) is synthesized and released in response to stressful stimuli as well as acute alcohol administration. The release of beta-E following exposure to an inescapable aversive situation may mediate behaviors that contribute to allostasis of the stress response. The present study examines the effects of beta-E on immobility in assays involving inescapable stress, both under basal conditions and after acute administration of EtOH. METHODS Female and male transgenic mice with varying capacities to translate beta-E were subjected to either the forced swim (FST, Experiment 1) or the tail suspension test (TST, Experiment 2). In Experiment 3, mice were divided into three groups based on hormonal status (male, female-estrous, and female-nonestrous) and injected with either 1 g/kg EtOH or equivolume saline 14 minutes prior to behavioral assessment on the TST. RESULTS Experiments 1 and 2 demonstrated a direct relationship between beta-E levels and immobility. There were also sex differences in behavior in these tests, with males displaying more immobility than females. A main effect of genotype in Experiment 3 replicated findings in Experiments 1 and 2. There was also an effect of EtOH (increasing immobility) and a significant interaction reflecting a particularly robust effect of the drug in mice with low beta-E. In addition, there were interactions between beta-E, EtOH effects, and hormonal status. CONCLUSIONS These findings support the contention that beta-E moderates behavioral responses to stressful stimuli and suggest a role for this peptide in coping behavior. Furthermore, the effects of EtOH on the response to stress may be mediated by beta-E. Sex differences in this influence may contribute to sex differences in disease susceptibility and expression.
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Affiliation(s)
- Elizabeth T Barfield
- Neuroscience Program, Department of Psychology, Furman University, Greenville, South Carolina 29609, USA
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Boyadjieva NI, Ortigüela M, Arjona A, Cheng X, Sarkar DK. Beta-endorphin neuronal cell transplant reduces corticotropin releasing hormone hyperresponse to lipopolysaccharide and eliminates natural killer cell functional deficiencies in fetal alcohol exposed rats. Alcohol Clin Exp Res 2009; 33:931-7. [PMID: 19320628 DOI: 10.1111/j.1530-0277.2009.00911.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Natural killer (NK) cell dysfunction is associated with hyperresponse of corticotropin releasing hormone (CRH) to immune challenge and with a loss of beta-endorphin (BEP) neurons in fetal alcohol exposed animals. Recently, we established a method to differentiate neural stem cells into BEP neurons using cyclic adenosine monophosphate (cAMP)-elevating agents in cultures. Hence, we determined whether in vitro differentiated BEP neurons could be used for reversing the compromised stress response and immune function in fetal alcohol exposed rats. METHODS To determine the effect of BEP neuron transplants on NK cell function, we implanted in vitro differentiated BEP neurons into the paraventricular nucleus of pubertal and adult male rats exposed to ethanol or control in utero. The functionality of transplanted BEP neurons was determined by measuring proopiomelanocortin (POMC) gene expression in these cells and their effects on CRH gene expression under basal and after lipopolysaccaride (LPS) challenge. In addition, the effectiveness of BEP neurons in activating NK cell functions is determined by measuring NK cell cytolytic activity and interferon-gamma (IFN-gamma) production in the spleen and in the peripheral blood mononuclear cell (PBMC) following cell transplantation. RESULTS We showed here that when these in vitro differentiated BEP neurons were transplanted into the hypothalamus, they maintain biological functions by producing POMC and reducing the CRH neuronal response to the LPS challenge. BEP neuronal transplants significantly increased NK cell cytolytic activity in the spleen and in the PBMC and increased plasma levels of IFN-gamma in control and fetal alcohol exposed rats. CONCLUSIONS These data further establish the BEP neuronal regulatory role in the control of CRH and NK cell cytolytic function and identify a possible novel therapy to treat stress hyperresponse and immune deficiency in fetal alcohol exposed subjects.
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Affiliation(s)
- Nadka I Boyadjieva
- Endocrine Program, Department of Animal Sciences, Rutgers-The State University of New Jersey, New Brunswick, NJ 08901, USA
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