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Podgórski R, Galiniak S, Mazur A, Podgórska D, Domin A. Serum Levels of Hormones Regulating Appetite in Patients with Fetal Alcohol Spectrum Disorders. Nutrients 2023; 15:4215. [PMID: 37836499 PMCID: PMC10574197 DOI: 10.3390/nu15194215] [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: 09/01/2023] [Revised: 09/28/2023] [Accepted: 09/28/2023] [Indexed: 10/15/2023] Open
Abstract
Prenatal alcohol exposure is the cause of impaired growth and a wide range of developmental and behavioral disorders in the child. Improper eating patterns are commonly associated with fetal alcohol spectrum disorders (FASD) and may contribute to poor nutrition and growth restriction. To date, there have been only a few studies investigating the hormonal regulation of appetite in patients with FASD. We analyzed the levels of neuropeptide Y (NPY), Agouti signaling protein (ASP), alpha-melanocyte-stimulating hormone (α-MSH), and kisspeptin (KISS1) in 57 patients with FASD and 23 healthy controls. A comparison of the hormone levels studied was also performed in subgroups of fetal alcohol syndrome (FAS) and neurobehavioral disorder associated with prenatal alcohol exposure (ND PAE), as well as in males and females. We have found no differences in hormone levels tested between affected individuals and the controls and between FASD subgroups. In addition, sex had no effect on hormone levels. However, we identified some associations between hormone concentrations and parameters describing the clinical status of patients with FASD. Most of them concerned ASP, which has shown a positive correlation with age and hormones involved in appetite and metabolism, such as proopiomelanocortin (POMC) and adrenocorticotropic hormone (ACTH). We have also found a negative correlation of α-MSH with age, BMI percentile, and glycated hemoglobin (HbA1c). Furthermore, we found a weak negative correlation of NPY with HbA1c. Although FASD has been associated with impaired child growth and development, including nutrition and puberty onset, we did not identify differences in the levels of the hormones studied, which may suggest that prenatal alcohol exposure does not affect the levels of these metabolites.
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Affiliation(s)
- Rafał Podgórski
- Department of Biochemistry, Institute of Medical Sciences, Medical College of Rzeszow University, 35-310 Rzeszow, Poland;
| | - Sabina Galiniak
- Department of Biochemistry, Institute of Medical Sciences, Medical College of Rzeszow University, 35-310 Rzeszow, Poland;
| | - Artur Mazur
- Department of Pediatric, Institute of Medical Sciences, Medical College of Rzeszow University, 35-310 Rzeszow, Poland; (A.M.); (A.D.)
| | - Dominika Podgórska
- Department of Rheumatology, Institute of Medical Sciences, Medical College of Rzeszow University, 35-310 Rzeszow, Poland;
| | - Agnieszka Domin
- Department of Pediatric, Institute of Medical Sciences, Medical College of Rzeszow University, 35-310 Rzeszow, Poland; (A.M.); (A.D.)
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2
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Leyrer-Jackson JM, Hood LE, Olive MF. Sex differences and the lack of effects of chemogenetic manipulation of pro-opiomelanocortin (POMC) neurons on alcohol consumption in male and female mice. Brain Res 2022; 1786:147901. [PMID: 35367433 DOI: 10.1016/j.brainres.2022.147901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 03/02/2022] [Accepted: 03/29/2022] [Indexed: 11/17/2022]
Abstract
The endogenous opioid system has been implicated in the rewarding and reinforcing effects of alcohol. Pro-opiomelanocortin (POMC) neurons located within the arcuate nucleus of the hypothalamus (ArcN) secrete multiple peptides associated with alcohol consumption, including β-endorphin (β-END), α-melanocyte stimulating hormone (α-MSH), and adrenocorticotropic hormone (ACTH). In this study, we utilized chemogenetics to bidirectionally modulate ArcN POMC neurons to determine their role in alcohol and saccharin consumption and regional levels of POMC-derived peptides. Male and female POMC-cre mice were infused with viral vectors designed for cre-dependent expression of either excitatory and inhibitory DREADDs or a control vector into the ArcN. Following recovery, animals were allowed to consume alcohol or saccharin using the drinking-in-the-dark (DID) paradigm of binge-like intake for 4 consecutive days. Prior to the final test session, animals were injected with clozapine-N-oxide (2.5 mg/kg, i.p.) for DREADD activation. Following the last DID session, animals were euthanized and the ArcN, VTA, amygdala and NAc were dissected and assessed for POMC peptide expression utilizing western blotting. We found that female mice consumed more alcohol than males during DID sessions 2-4, and that chemogenetic activation had no effect on alcohol or saccharin consumption in either sex. We found that β-END expression within the ArcN positively correlated with alcohol consumption. Given the molecular and functional heterogeneity of ArcN POMC neurons, future studies are needed to assess the effects of modulation of specific subpopulations of these neurons within the ArcN on consumption of rewarding substances such as alcohol and saccharin.
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Affiliation(s)
| | - Lauren E Hood
- Department of Psychology, Arizona State University, Tempe, AZ 85281, USA
| | - M Foster Olive
- Department of Psychology, Arizona State University, Tempe, AZ 85281, USA
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3
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Sharfman N, Gilpin NW. The Role of Melanocortin Plasticity in Pain-Related Outcomes After Alcohol Exposure. Front Psychiatry 2021; 12:764720. [PMID: 34803772 PMCID: PMC8599269 DOI: 10.3389/fpsyt.2021.764720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 10/05/2021] [Indexed: 11/13/2022] Open
Abstract
The global COVID-19 pandemic has shone a light on the rates and dangers of alcohol misuse in adults and adolescents in the US and globally. Alcohol exposure during adolescence causes persistent molecular, cellular, and behavioral changes that increase the risk of alcohol use disorder (AUD) into adulthood. It is established that alcohol abuse in adulthood increases the likelihood of pain hypersensitivity and the genesis of chronic pain, and humans report drinking alcohol to relieve pain symptoms. However, the longitudinal effects of alcohol exposure on pain and the underlying CNS signaling that mediates it are understudied. Specific brain regions mediate pain effects, alcohol effects, and pain-alcohol interactions, and neural signaling in those brain regions is modulated by neuropeptides. The CNS melanocortin system is sensitive to alcohol and modulates pain sensitivity, but this system is understudied in the context of pain-alcohol interactions. In this review, we focus on the role of melanocortin signaling in brain regions sensitive to alcohol and pain, in particular the amygdala. We also discuss interactions of melanocortins with other peptide systems, including the opioid system, as potential mediators of pain-alcohol interactions. Therapeutic strategies that target the melanocortin system may mitigate the negative consequences of alcohol misuse during adolescence and/or adulthood, including effects on pain-related outcomes.
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Affiliation(s)
- Nathan Sharfman
- Department of Physiology, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, LA, United States
| | - Nicholas W Gilpin
- Department of Physiology, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, LA, United States.,Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans, LA, United States.,Alcohol and Drug Abuse Center of Excellence, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, LA, United States.,Southeast Louisiana VA Healthcare System (SLVHCS), New Orleans, LA, United States
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4
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Flores-Bastías O, Gómez GI, Orellana JA, Karahanian E. Activation of Melanocortin-4 Receptor by a Synthetic Agonist Inhibits Ethanolinduced Neuroinflammation in Rats. Curr Pharm Des 2020; 25:4799-4805. [PMID: 31840601 DOI: 10.2174/1381612825666191216145153] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 12/10/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND High ethanol intake induces a neuroinflammatory response resulting in the subsequent maintenance of chronic alcohol consumption. The melanocortin system plays a pivotal role in the modulation of alcohol consumption. Interestingly, it has been shown that the activation of melanocortin-4 receptor (MC4R) in the brain decreases the neuroinflammatory response in models of brain damage other than alcohol consumption, such as LPS-induced neuroinflammation, cerebral ischemia, glutamate excitotoxicity, and spinal cord injury. OBJECTIVES In this work, we aimed to study whether MC4R activation by a synthetic MC4R-agonist peptide prevents ethanol-induced neuroinflammation, and if alcohol consumption produces changes in MC4R expression in the hippocampus and hypothalamus. METHODS Ethanol-preferring Sprague Dawley rats were selected offering access to 20% ethanol on alternate days for 4 weeks (intermittent access protocol). After this time, animals were i.p. administered an MC4R agonist peptide in the last 2 days of the protocol. Then, the expression of the proinflammatory cytokines interleukin 6 (IL-6), interleukin 1-beta (IL-1β), and tumor necrosis factor-alpha (TNF-α) were measured in the hippocampus, hypothalamus and prefrontal cortex. It was also evaluated if ethanol intake produces alterations in the expression of MC4R in the hippocampus and the hypothalamus. RESULTS Alcohol consumption increased the expression of MC4R in the hippocampus and the hypothalamus. The administration of the MC4R agonist reduced IL-6, IL-1β and TNF-α levels in hippocampus, hypothalamus and prefrontal cortex, to those observed in control rats that did not drink alcohol. CONCLUSION High ethanol consumption produces an increase in the expression of MC4R in the hippocampus and hypothalamus. The administration of a synthetic MC4R-agonist peptide prevents neuroinflammation induced by alcohol consumption in the hippocampus, hypothalamus, and prefrontal cortex. These results could explain the effect of α-MSH and other synthetic MC4R agonists in decreasing alcohol intake through the reduction of the ethanol-induced inflammatory response in the brain.
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Affiliation(s)
- Osvaldo Flores-Bastías
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Chile.,Research Center for the Study of Alcohol Drinking Behavior in Adolescents, Santiago, Chile
| | - Gonzalo I Gómez
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Chile.,Research Center for the Study of Alcohol Drinking Behavior in Adolescents, Santiago, Chile
| | - Juan A Orellana
- Research Center for the Study of Alcohol Drinking Behavior in Adolescents, Santiago, Chile.,Departamento de Neurología, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Eduardo Karahanian
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Chile.,Research Center for the Study of Alcohol Drinking Behavior in Adolescents, Santiago, Chile
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5
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Müschen LH, Rhein M, Hoppe V, John N, Schwabe K, Frieling H, Bleich S, Muschler MAN. Alcohol Withdrawal and Proopiomelanocortin Neuropeptides in an Animal Model of Alcohol Dependence. Neuropsychobiology 2020; 78:118-127. [PMID: 31117084 DOI: 10.1159/000499844] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 03/19/2019] [Indexed: 12/30/2022]
Abstract
BACKGROUND Alcohol is one of the leading threats to health worldwide. Craving for alcohol makes abstinence a difficult challenge by maintaining alcohol dependence. Many studies suppose the hypothalamic-pituitary-adrenal axis, especially the proopiomelanocortin (POMC)-derived neuropeptides, to mediate craving during withdrawal in alcohol dependence. Evidence is available that the two POMC proteins, α-melanocyte-stimulating hormone (α-MSH) and β-endorphin (β-END) are altered by alcohol consumption and influence alcohol consumption, respectively. OBJECTIVES We investigated the dynamics of α-MSH and β-END during alcohol withdrawal and the influence of intraperitoneal administration of either α-MSH or β-END in an established rodent model (Wistar rats) for alcohol dependence. RESULTS After long-term alcohol self-administration over 12 months and repeated deprivation periods for 3 days, we found a significant decrease in α-MSH levels during withdrawal in rodents (p = 0.006) compared to controls, while β-END levels remained unchanged. Treatment with intraperitoneally administered α-MSH and β-END did not affect alcohol drinking behavior after deprivation. CONCLUSION We demonstrate the effects of alcohol deprivation on α-MSH in alcohol-dependent rodents, which appear to mimic α-MSH alteration found after fasting periods during appetite regulation. Therefore, low α-MSH levels are a possible indicator for craving in alcohol-dependent individuals and hence would be a potential target for anti-craving treatment.
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Affiliation(s)
- Lars Hendrik Müschen
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany.,Departmentof Neurology, Hannover Medical School, Hannover, Germany
| | - Mathias Rhein
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany.,Laboratory for Molecular Neuroscience, Hannover Medical School, Hannover, Germany
| | - Viktoria Hoppe
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany.,Department of Gynecology, Franziskus Hospital, Bielefeld, Germany
| | - Nadine John
- Department of Neurosurgery, Hannover Medical School, Hannover, Germany
| | - Kerstin Schwabe
- Department of Neurosurgery, Hannover Medical School, Hannover, Germany
| | - Helge Frieling
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany.,Laboratory for Molecular Neuroscience, Hannover Medical School, Hannover, Germany
| | - Stefan Bleich
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany.,Laboratory for Molecular Neuroscience, Hannover Medical School, Hannover, Germany
| | - Marc André Nicolas Muschler
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Hannover, Germany, .,Laboratory for Molecular Neuroscience, Hannover Medical School, Hannover, Germany,
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6
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Flores-Bastías O, Adriasola-Carrasco A, Karahanian E. Activation of Melanocortin-4 Receptor Inhibits Both Neuroinflammation Induced by Early Exposure to Ethanol and Subsequent Voluntary Alcohol Intake in Adulthood in Animal Models: Is BDNF the Key Mediator? Front Cell Neurosci 2020; 14:5. [PMID: 32063838 PMCID: PMC6997842 DOI: 10.3389/fncel.2020.00005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 01/10/2020] [Indexed: 12/31/2022] Open
Abstract
The concept that neuroinflammation induced by excessive alcohol intake in adolescence triggers brain mechanisms that perpetuate consumption has strengthened in recent years. The melanocortin system, composed of the melanocortin 4 receptor (MC4R) and its ligand α-melanocyte-stimulating hormone (α-MSH), has been implicated both in modulation of alcohol consumption and in ethanol-induced neuroinflammation decrease. Chronic alcohol consumption in adolescent rats causes a decrease in an α-MSH release by the hypothalamus, while the administration of synthetic agonists of MC4R causes a decrease in neuroinflammation and a decrease in voluntary alcohol consumption. However, the mechanism that connects the activation of MC4R with the decrease of both neuroinflammation and voluntary alcohol consumption has not been elucidated. Brain-derived neurotrophic factor (BDNF) has been implicated in alcohol drinking motivation, dependence and withdrawal, and its levels are reduced in alcoholics. Deficiencies in BDNF levels increased ethanol self-administration in rats. Further, BDNF triggers important anti-inflammatory effects in the brain, and this could be one of the mechanisms by which BDNF reduces chronic alcohol intake. Interestingly, MC4R signaling induces BDNF expression through the activation of the cAMP-responsive element-binding protein (CREB). We hypothesize that ethanol exposure during adolescence decreases the expression of α-MSH and hence MC4R signaling in the hippocampus, leading to a lower BDNF activity that causes dramatic changes in the brain (e.g., neuroinflammation and decreased neurogenesis) that predispose to maintain alcohol abuse until adulthood. The activation of MC4R either by α-MSH or by synthetic agonist peptides can induce the expression of BDNF, which would trigger several processes that lead to lower alcohol consumption.
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Affiliation(s)
- Osvaldo Flores-Bastías
- Institute of Biomedical Sciences, Faculty of Health Sciences, Universidad Autónoma de Chile, Santiago, Chile.,Research Center for the Study of Alcohol Drinking Behavior in Adolescents, Universidad Autónoma de Chile, Santiago, Chile
| | - Alfredo Adriasola-Carrasco
- Institute of Biomedical Sciences, Faculty of Health Sciences, Universidad Autónoma de Chile, Santiago, Chile
| | - Eduardo Karahanian
- Institute of Biomedical Sciences, Faculty of Health Sciences, Universidad Autónoma de Chile, Santiago, Chile.,Research Center for the Study of Alcohol Drinking Behavior in Adolescents, Universidad Autónoma de Chile, Santiago, Chile
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7
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Lerma-Cabrera JM, Carvajal F, Garbutt JC, Navarro M, Thiele TE. The melanocortin system as a potential target for treating alcohol use disorders: A review of pre-clinical data. Brain Res 2019; 1730:146628. [PMID: 31891691 DOI: 10.1016/j.brainres.2019.146628] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 12/02/2019] [Accepted: 12/26/2019] [Indexed: 12/17/2022]
Abstract
The melanocortin (MC) system consists of neuropeptides that are cleaved from the polypeptide precursor proopiomelanocortin (POMC). In the brain, MC neuropeptides signal primarily through the MC-3 and MC-4 receptors, which are widely expressed throughout the brain. While the MC system has been largely studied for its role in food intake and body weight regulation, converging evidence has emerged over approximately the last 20-years showing that alcohol (ethanol), and other drugs of abuse influence the central MC system, and that manipulating MC receptor signalling modulates ethanol intake. Although there is divergent evidence, the wealth of data appears to suggest that activating MC signalling, primarily through the MC-4 receptor, is protective against excessive ethanol consumption. In the present review, we first describe the MC system and then detail how ethanol exposure and consumption alters central MC and MC-receptor expression and levels. This is followed by a review of the data, from pharmacological and genetic studies, which show that manipulations of MC receptor activity alter ethanol intake. We then briefly highlight studies implicating a role for the MC system in modulating neurobiological responses and intake of other drugs of abuse, including amphetamine, cocaine and opioids. Finally, we introduce relatively new observations that the drug, bupropion (BUP), a drug that activates central MC activity, significantly reduces ethanol intake in rodent models when administered alone and in combination with the non-selective opioid receptor antagonist, naltrexone. Phase II clinical trials are currently underway to assess the efficacy of BUP as a treatment for alcohol use disorders.
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Affiliation(s)
| | | | - James C Garbutt
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Montserrat Navarro
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Psychology & Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Todd E Thiele
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Psychology & Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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8
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Orellana JA, Cerpa W, Carvajal MF, Lerma-Cabrera JM, Karahanian E, Osorio-Fuentealba C, Quintanilla RA. New Implications for the Melanocortin System in Alcohol Drinking Behavior in Adolescents: The Glial Dysfunction Hypothesis. Front Cell Neurosci 2017; 11:90. [PMID: 28424592 PMCID: PMC5380733 DOI: 10.3389/fncel.2017.00090] [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: 11/15/2016] [Accepted: 03/15/2017] [Indexed: 12/12/2022] Open
Abstract
Alcohol dependence causes physical, social, and moral harms and currently represents an important public health concern. According to the World Health Organization (WHO), alcoholism is the third leading cause of death worldwide, after tobacco consumption and hypertension. Recent epidemiologic studies have shown a growing trend in alcohol abuse among adolescents, characterized by the consumption of large doses of alcohol over a short time period. Since brain development is an ongoing process during adolescence, short- and long-term brain damage associated with drinking behavior could lead to serious consequences for health and wellbeing. Accumulating evidence indicates that alcohol impairs the function of different components of the melanocortin system, a major player involved in the consolidation of addictive behaviors during adolescence and adulthood. Here, we hypothesize the possible implications of melanocortins and glial cells in the onset and progression of alcohol addiction. In particular, we propose that alcohol-induced decrease in α-MSH levels may trigger a cascade of glial inflammatory pathways that culminate in altered gliotransmission in the ventral tegmental area and nucleus accumbens (NAc). The latter might potentiate dopaminergic drive in the NAc, contributing to increase the vulnerability to alcohol dependence and addiction in the adolescence and adulthood.
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Affiliation(s)
- Juan A Orellana
- Centro de Investigación y Estudio del Consumo de Alcohol en AdolescentesSantiago, Chile.,Laboratorio de Neurociencias, Departamento de Neurología, Escuela de Medicina, Facultad de Medicina, Pontificia Universidad Católica de ChileSantiago, Chile
| | - Waldo Cerpa
- Centro de Investigación y Estudio del Consumo de Alcohol en AdolescentesSantiago, Chile.,Laboratorio de Función y Patología Neuronal, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de ChileSantiago, Chile
| | - Maria F Carvajal
- Centro de Investigación y Estudio del Consumo de Alcohol en AdolescentesSantiago, Chile.,Unidad de Neurociencia, Centro de Investigación Biomédica, Universidad Autónoma de ChileSantiago, Chile
| | - José M Lerma-Cabrera
- Centro de Investigación y Estudio del Consumo de Alcohol en AdolescentesSantiago, Chile.,Unidad de Neurociencia, Centro de Investigación Biomédica, Universidad Autónoma de ChileSantiago, Chile
| | - Eduardo Karahanian
- Centro de Investigación y Estudio del Consumo de Alcohol en AdolescentesSantiago, Chile.,Unidad de Neurociencia, Centro de Investigación Biomédica, Universidad Autónoma de ChileSantiago, Chile
| | - Cesar Osorio-Fuentealba
- Centro de Investigación y Estudio del Consumo de Alcohol en AdolescentesSantiago, Chile.,Facultad de Kinesiología, Artes y Educación Física, Universidad Metropolitana de Ciencias de la EducaciónSantiago, Chile
| | - Rodrigo A Quintanilla
- Centro de Investigación y Estudio del Consumo de Alcohol en AdolescentesSantiago, Chile.,Laboratory of Neurodegenerative Diseases, Universidad Autónoma de ChileSantiago, Chile
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9
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Navarro M. The Role of the Melanocortin System in Drug and Alcohol Abuse. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2017; 136:121-150. [DOI: 10.1016/bs.irn.2017.06.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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10
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Sprow GM, Rinker JA, Lowery-Gointa EG, Sparrow AM, Navarro M, Thiele TE. Lateral hypothalamic melanocortin receptor signaling modulates binge-like ethanol drinking in C57BL/6J mice. Addict Biol 2016; 21:835-46. [PMID: 25975524 DOI: 10.1111/adb.12264] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Binge ethanol drinking is a highly pervasive and destructive behavior yet the underlying neurobiological mechanisms remain poorly understood. Recent work suggests that overlapping neurobiological mechanisms modulate feeding disorders and excessive ethanol intake, and converging evidence indicates that the melanocortin (MC) system may be a promising candidate. The aims of the present work were to examine how repeated binge-like ethanol drinking, using the 'drinking in the dark' (DID) protocol, impacts key peptides within the MC system and if site-specific manipulation of MC receptor (MCR) signaling modulates binge-like ethanol drinking. Male C57BL/6J mice were exposed to one, three or six cycles of binge-like ethanol, sucrose or water drinking, after which brain tissue was processed via immunohistochemistry (IHC) for analysis of key MC peptides, including alpha-melanocyte stimulating hormone (α-MSH) and agouti-related protein (AgRP). Results indicated that α-MSH expression was selectively decreased, while AgRP expression was selectively increased, within specific hypothalamic subregions following repeated binge-like ethanol drinking. To further explore this relationship, we used site-directed drug delivery techniques to agonize or antagonize MCRs within the lateral hypothalamus (LH). We found that the nonselective MCR agonist melanotan-II (MTII) blunted, while the nonselective MCR antagonist AgRP augmented, binge-like ethanol consumption when delivered into the LH. As these effects were region-specific, the present results suggest that a more thorough understanding of the MC neurocircuitry within the hypothalamus will help provide novel insight into the mechanisms that modulate excessive binge-like ethanol intake and may help uncover new therapeutic targets aimed at treating alcohol abuse disorders.
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Affiliation(s)
- Gretchen M. Sprow
- Department of Psychology and Neuroscience; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - Jennifer A. Rinker
- Department of Psychology and Neuroscience; University of North Carolina at Chapel Hill; Chapel Hill NC USA
- Bowles Center for Alcohol Studies; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - Emily G. Lowery-Gointa
- Department of Psychology and Neuroscience; University of North Carolina at Chapel Hill; Chapel Hill NC USA
- Bowles Center for Alcohol Studies; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - Angela M. Sparrow
- Department of Psychology and Neuroscience; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - Montserrat Navarro
- Department of Psychology and Neuroscience; University of North Carolina at Chapel Hill; Chapel Hill NC USA
- Bowles Center for Alcohol Studies; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - Todd E. Thiele
- Department of Psychology and Neuroscience; University of North Carolina at Chapel Hill; Chapel Hill NC USA
- Bowles Center for Alcohol Studies; University of North Carolina at Chapel Hill; Chapel Hill NC USA
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11
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Barson JR, Leibowitz SF. Hypothalamic neuropeptide signaling in alcohol addiction. Prog Neuropsychopharmacol Biol Psychiatry 2016; 65:321-9. [PMID: 25689818 PMCID: PMC4537397 DOI: 10.1016/j.pnpbp.2015.02.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 01/30/2015] [Accepted: 02/09/2015] [Indexed: 11/27/2022]
Abstract
The hypothalamus is now known to regulate alcohol intake in addition to its established role in food intake, in part through neuromodulatory neurochemicals termed neuropeptides. Certain orexigenic neuropeptides act in the hypothalamus to promote alcohol drinking, although they affect different aspects of the drinking response. These neuropeptides, which include galanin, the endogenous opioid enkephalin, and orexin/hypocretin, appear to stimulate alcohol intake not only through mechanisms that promote food intake but also by enhancing reward and reinforcement from alcohol. Moreover, these neuropeptides participate in a positive feedback relationship with alcohol, whereby they are upregulated by alcohol intake to promote even further consumption. They contrast with other orexigenic neuropeptides, such as melanin-concentrating hormone and neuropeptide Y, which promote alcohol intake under limited circumstances, are not consistently stimulated by alcohol, and do not enhance reward. They also contrast with neuropeptides that can be anorexigenic, including the endogenous opioid dynorphin, corticotropin-releasing factor, and melanocortins, which act in the hypothalamus to inhibit alcohol drinking as well as reward and therefore counter the ingestive drive promoted by orexigenic neuropeptides. Thus, while multiple hypothalamic neuropeptides may work together to regulate different aspects of the alcohol drinking response, excessive signaling from orexigenic neuropeptides or inadequate signaling from anorexigenic neuropeptides can therefore allow alcohol drinking to become dysregulated.
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Affiliation(s)
- Jessica R. Barson
- Laboratory of Behavioral Neurobiology, The Rockefeller University, 1230 York Avenue, Box 278, New York, NY, 10065 USA
| | - Sarah F. Leibowitz
- Laboratory of Behavioral Neurobiology, The Rockefeller University, 1230 York Avenue, Box 278, New York, NY, 10065 USA
,Corresponding author at: Laboratory of Behavioral Neurobiology, The Rockefeller University, 1230 York Avenue, Box 278, New York, NY, 10065 USA. Tel.: +1 212 327 8378; fax: +1 212 327 8447
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12
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Shelkar GP, Kale AD, Singh U, Singru PS, Subhedar NK, Kokare DM. Alpha-melanocyte stimulating hormone modulates ethanol self-administration in posterior ventral tegmental area through melanocortin-4 receptors. Addict Biol 2015; 20:302-15. [PMID: 24635847 DOI: 10.1111/adb.12126] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Although the role of alpha-melanocyte stimulating hormone (α-MSH) in alcohol seeking behaviour in rats has been demonstrated, the underlying mechanisms are not understood. Herein, we test the hypothesis that α-MSH might have a permissive effect in promoting the reward action of ethanol. Rats were implanted with cannulae targeted at the posterior ventral tegmental area (pVTA), because the site is sensitive to reinforcing effects of ethanol. These rats were trained to self-administer ethanol in standard two-lever (active/inactive) operant chamber test. Each active lever press resulted in self-administration of 100 nl of ethanol (100-300 mg%) containing solution. Over a period of 7 days, ethanol significantly increased the number of lever presses, which was considered as a measure of reward. Because ethanol at 200 mg% resulted in maximum number of lever presses (∼18-20 lever presses/30-minute session), the dose was employed in further studies. While prior administration of melanocortin (MC) agonists, α-MSH or [Nle4,D-Phe7]-alpha-MSH into pVTA, resulted in an 89% increase in lever presses, the response was attenuated following pre-treatment with MC4 receptors (MC4R) antagonist, HS014. In an immunohistochemical study, the brains of rats that were trained to self-infuse ethanol showed significantly increased α-MSH immunoreactivity in the nucleus accumbens shell, bed nucleus of stria terminalis and arcuate nucleus of the hypothalamus. In the pVTA, α-MSH fibres were found to run close to the dopamine cells, labelled with tyrosine hydroxylase antibodies. We suggest that α-MSH-MC4R system in the pVTA might be a part of the neuroadaptive mechanism underlying ethanol addiction.
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Affiliation(s)
- Gajanan P. Shelkar
- Department of Pharmaceutical Sciences; Rashtrasant Tukadoji Maharaj Nagpur University; Nagpur Maharashtra India
| | - Atmaram D. Kale
- Department of Pharmaceutical Sciences; Rashtrasant Tukadoji Maharaj Nagpur University; Nagpur Maharashtra India
| | - Uday Singh
- School of Biological Sciences; National Institute of Science Education & Research (NISER); Institute of Physics Campus; Bhubaneswar Orrisa India
| | - Praful S. Singru
- School of Biological Sciences; National Institute of Science Education & Research (NISER); Institute of Physics Campus; Bhubaneswar Orrisa India
| | | | - Dadasaheb M. Kokare
- Department of Pharmaceutical Sciences; Rashtrasant Tukadoji Maharaj Nagpur University; Nagpur Maharashtra India
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Olney JJ, Navarro M, Thiele TE. Targeting central melanocortin receptors: a promising novel approach for treating alcohol abuse disorders. Front Neurosci 2014; 8:128. [PMID: 24917782 PMCID: PMC4042890 DOI: 10.3389/fnins.2014.00128] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 05/08/2014] [Indexed: 12/30/2022] Open
Abstract
The melanocortin (MC) peptides are produced centrally by propiomelanocortin (POMC) neurons within the arcuate nucleus of the hypothalamus and act through five seven-transmembrane G-protein coupled melanocortin receptor (MCR) subtypes. The MC3R and MC4R subtypes, the most abundant central MCRs, are widely expressed in brain regions known to modulate neurobiological responses to ethanol, including regions of the hypothalamus and extended amygdala. Agouti-related protein (AgRP), also produced in the arcuate nucleus, is secreted in terminals expressing MCRs and functions as an endogenous MCR antagonist. This review highlights recent genetic and pharmacological findings that have implicated roles for the MC and AgRP systems in modulating ethanol consumption. Ethanol consumption is associated with significant alterations in the expression levels of various MC peptides/protein, which suggests that ethanol-induced perturbations of MC/AgRP signaling may modulate excessive ethanol intake. Consistently, MCR agonists decrease, and AgRP increases, ethanol consumption in mice. MCR agonists fail to blunt ethanol intake in mutant mice lacking the MC4R, suggesting that the protective effects of MCR agonists are modulated by the MC4R. Interestingly, recent evidence reveals that MCR agonists are more effective at blunting binge-like ethanol intake in mutant mice lacking the MC3R, suggesting that the MC3R has opposing effects on the MC4R. Finally, mutant mice lacking AgRP exhibit blunted voluntary and binge-like ethanol drinking, consistent with pharmacological studies. Collectively, these preclinical observations provide compelling evidence that compounds that target the MC system may provide therapeutic value for treating alcohol abuse disorders and that the utilization of currently available MC-targeting compounds- such as those being used to treat eating disorders- may be used as effective treatments to this end.
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Affiliation(s)
- Jeffrey J Olney
- Department of Psychology, University of North Carolina Chapel Hill, NC, USA
| | - Montserrat Navarro
- Department of Psychology, University of North Carolina Chapel Hill, NC, USA
| | - Todd E Thiele
- Department of Psychology, University of North Carolina Chapel Hill, NC, USA ; Bowles Center for Alcohol Studies, University of North Carolina Chapel Hill, NC, USA
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Lerma-Cabrera JM, Carvajal F, Alcaraz-Iborra M, de la Fuente L, Navarro M, Thiele TE, Cubero I. Adolescent binge-like ethanol exposure reduces basal α-MSH expression in the hypothalamus and the amygdala of adult rats. Pharmacol Biochem Behav 2013; 110:66-74. [PMID: 23792540 DOI: 10.1016/j.pbb.2013.06.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 06/03/2013] [Accepted: 06/09/2013] [Indexed: 01/31/2023]
Abstract
Melanocortins (MC) are central peptides that have been implicated in the modulation of ethanol consumption. There is experimental evidence that chronic ethanol exposure reduces α-MSH expression in the limbic and hypothalamic brain regions and alters central pro-opiomelanocortin (POMC) mRNA activity in adult rats. Adolescence is a critical developmental period of high vulnerability in which ethanol exposure alters corticotropin releasing factor, neuropeptide Y, substance P and neurokinin neuropeptide activities, all of which have key roles in ethanol consumption. Given the involvement of MC and the endogenous inverse agonist AgRP in ethanol drinking, here we evaluate whether a binge-like pattern of ethanol treatment during adolescence has a relevant impact on basal and/or ethanol-stimulated α-MSH and AgRP activities during adulthood. To this end, adolescent Sprague-Dawley rats (beginning at PND25) were pre-treated with either saline (SP group) or binge-like ethanol exposure (BEP group; 3.0 g/kg given in intraperitoneal (i.p.) injections) of one injection per day over two consecutive days, followed by 2 days without injections, repeated for a total of 8 injections. Following 25 ethanol-free days, we evaluated α-MSH and AgRP immunoreactivity (IR) in the limbic and hypothalamic nuclei of adult rats (PND63) in response to ethanol (1.5 or 3.0 g/kgi.p.) and saline. We found that binge-like ethanol exposure during adolescence significantly reduced basal α-MSH IR in the central nucleus of the amygdala (CeA), the arcuate nucleus (Arc) and the paraventricular nucleus of the hypothalamus (PVN) during adulthood. Additionally, acute ethanol elicited AgRP IR in the Arc. Rats given the adolescent ethanol treatment required higher doses of ethanol than saline-treated rats to express AgRP. In light of previous evidence that endogenous MC and AgRP regulate ethanol intake through MC-receptor signaling, we speculate that the α-MSH and AgRP disturbances induced by binge-like ethanol exposure during adolescence may contribute to excessive ethanol consumption during adulthood.
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γ1- and γ2-melanocyte stimulating hormones induce central anxiogenic effects and potentiate ethanol withdrawal responses in the elevated plus-maze test in mice. Pharmacol Biochem Behav 2009; 92:267-71. [DOI: 10.1016/j.pbb.2008.12.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2008] [Revised: 11/19/2008] [Accepted: 12/08/2008] [Indexed: 11/17/2022]
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Transient up-regulation of cocaine- and amphetamine-regulated transcript peptide (CART) immunoreactivity following ethanol withdrawal in rat hypothalamus. Brain Res 2008; 1240:119-31. [PMID: 18823957 DOI: 10.1016/j.brainres.2008.09.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2008] [Revised: 09/02/2008] [Accepted: 09/04/2008] [Indexed: 11/21/2022]
Abstract
We investigated the profile of CART immunoreactivity in some discrete hypothalamic nuclei following chronic ethanol treatment and withdrawal conditions. Adult, male, Sprague-Dawley rats were fed with liquid diet (pair-fed) or liquid diet containing ethanol (ethanol-fed) for 15 days. Thereafter, all the animals were given access to ethanol free nutritionally balanced liquid diet and killed at 0, 24, 48 and 72 h post-withdrawal, and their brains processed for immunocytochemistry using monoclonal antibodies against CART. CART-immunoreactive fibers, but not the cells, were significantly increased in the paraventricular nucleus (PVN). However, the profile of CART-immunoreactive cells and/or fibers in the periventricular area (PeA), arcuate nucleus (ARC), perifornical area inclusive of lateral hypothalamus (LH) and tuber cinereum (TC), dorsomedial (DMH), and ventromedial (VMH) hypothalamus at the 0 h ethanol withdrawal time point was quite similar to that in the pair-fed control rats. Twenty-four hours following ethanol withdrawal, the immunoreactivity in all these areas was dramatically increased. While significant reduction in CART immunoreactivity was noticed in the PVN, PeA, ARC and VMH at 48 h, immunoreactive profile was restored to normal by 72 h post-ethanol withdrawal. The immunoreactive profile in the LH, TC and DMH resembled that of the pair-fed groups at 48 and 72 h post-withdrawal intervals. However, CART-immunoreactive profile in the supraoptic nucleus did not respond to the chronic ethanol treatment and/or withdrawal. We suggest that transient up-regulation of CART in some discrete hypothalamic nuclei following ethanol withdrawal, at least in part, may contribute to the pathogenesis of ethanol withdrawal-induced symptoms like anxiety and anorexia.
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Kokare DM, Singru PS, Dandekar MP, Chopde CT, Subhedar NK. Involvement of alpha-melanocyte stimulating hormone (alpha-MSH) in differential ethanol exposure and withdrawal related depression in rat: neuroanatomical-behavioral correlates. Brain Res 2008; 1216:53-67. [PMID: 18499089 DOI: 10.1016/j.brainres.2008.03.064] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2007] [Revised: 03/22/2008] [Accepted: 03/24/2008] [Indexed: 10/22/2022]
Abstract
We investigated the involvement of alpha-melanocyte stimulating hormone (alpha-MSH) following acute, chronic and withdrawal treatments of ethanol with reference to depression. The degree of depression was evaluated using Porsolt's forced swim test. While intracerebroventricular (i.c.v.) alpha-MSH (100-400 ng/rat) dose-dependently increased the immobility, opposite response was observed following administration of selective MC4 receptor antagonist HS014 (0.01-0.07 ng/rat, i.c.v.). The anti-immobility effect of acute ethanol (1-2 g/kg), injected via intra-peritoneal route (i.p.), was suppressed by central administration of alpha-MSH (100 ng/rat, i.c.v.), but was enhanced following pretreatment with HS014 (0.01 ng/rat, i.c.v.). Chronic ethanol resulted in increased immobility time, while further augmentation in immobility was noticed following ethanol withdrawal. However, concomitant HS014 (0.01 ng/rat, i.c.v.) treatment prevented tolerance as well as attenuated enhanced immobility in ethanol-withdrawn rats. Acute administration of HS014 (0.01-0.03 ng/rat, i.c.v.), at 24h post-withdrawal time point, also antagonized the ethanol withdrawal immobility in rats. The profile of alpha-MSH-immunoreactivity in the paraventricular (PVN), arcuate (ARC), paraventricular thalamic (PVT), dorsomedial hypothalamic-dorsal (DMNd) and -ventral (DMNv) nuclei, lateral hypothalamus (LH) and central nucleus of amygdala (CeA) was investigated with immunocytochemistry. Acute ethanol significantly reduced the alpha-MSH-immunoreactivity in the cells and fibers of ARC, and fibers in the PVN, DMNd, DMNv and CeA. While chronic ethanol treatment significantly increased the alpha-MSH-immunoreactivity as compared to the pair-fed control group, further augmentation was noticed following 24 h ethanol withdrawal. However, the alpha-MSH-immunoreactive profile in the PVT and LH did not respond. alpha-MSH in discrete areas may play a role in ethanol-induced antidepressant-like response and withdrawal-induced depression.
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Affiliation(s)
- Dadasaheb M Kokare
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University Campus, Nagpur, 440 033, India
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Navarro M, Cubero I, Knapp DJ, Breese GR, Thiele TE. Decreased immunoreactivity of the melanocortin neuropeptide alpha-melanocyte-stimulating hormone (alpha-MSH) after chronic ethanol exposure in Sprague-Dawley rats. Alcohol Clin Exp Res 2007; 32:266-76. [PMID: 18162070 PMCID: PMC2365503 DOI: 10.1111/j.1530-0277.2007.00578.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND The melanocortin (MC) system is composed of peptides that are cleaved from the polypeptide precursor proopiomelanocortin (POMC). Recent pharmacologic and genetic evidence suggests that MC receptor (MCR) signaling modulates neurobiologic responses to ethanol and ethanol intake. Because ethanol decreases POMC mRNA levels, we determined if exposure to an ethanol-containing diet (ED) would significantly reduce central immunoreactivity of the MC peptide alpha-MSH in rats. We also determined if ethanol exposure would alter the immunoreactivity of agouti-related protein (AgRP), an endogenous MCR antagonist. METHODS Male Sprague-Dawley rats were given 18 days of access to normal rodent chow or a control diet (CD), or short-term (4 days) or long-term (18 days) access to an ED. At the end of the study, rats were perfused with 4% paraformaldehyde and their brains were sectioned into two sets for processing with alpha-MSH or AgRP immunohistochemistry. RESULTS Rats exposed to an ED showed significant reductions of central alpha-MSH immunoreactivity relative to rats exposed to a control diet (CD) or normal rodent chow. Ethanol-induced reductions of alpha-MSH immunoreactivity were site-specific and were noted in regions of the hypothalamus and extended amygdala, as well as the paraventricular nucleus of the thalamus. Because there were no differences in body weights or caloric intake between the CD and ED groups, reductions of alpha-MSH immunoreactivity in ED-treated rats are best explained by ethanol exposure rather than altered energy balance. No significant ethanol-induced alterations in hypothalamic AgRP immunoreactivity were detected. CONCLUSIONS The present study shows that ethanol site specifically reduces alpha-MSH immunoreactivity in rat brain. These observations, in tandem with recent pharmacologic and genetic studies, suggest that the endogenous MC system modulates neurobiologic responses to ethanol. Thus, compounds which target MCRs may prove to have therapeutic value in the treatment of excessive ethanol consumption and/or the symptoms associated with ethanol withdrawal.
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Affiliation(s)
- Montserrat Navarro
- Department of Psychology, University of North Carolina, Chapel Hill, North Carolina 27599-3270, USA
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Dembele K, Yao XH, Chen L, Nyomba BLG. Intrauterine ethanol exposure results in hypothalamic oxidative stress and neuroendocrine alterations in adult rat offspring. Am J Physiol Regul Integr Comp Physiol 2006; 291:R796-802. [PMID: 16614051 DOI: 10.1152/ajpregu.00633.2005] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Prenatal ethanol (EtOH) exposure is associated with low birth weight, followed by increased appetite, catch-up growth, insulin resistance, and impaired glucose tolerance in the rat offspring. Because EtOH can induce oxidative stress, which is a putative mechanism of insulin resistance, and because of the central role of the hypothalamus in the regulation of energy homeostasis and insulin action, we investigated whether prenatal EtOH exposure causes oxidative damage to the hypothalamus, which may alter its function. Female rats were given EtOH by gavage throughout pregnancy. At birth, their offspring were smaller than those of non-EtOH rats. Markers of oxidative stress and expression of neuropeptide Y and proopiomelanocortin (POMC) were determined in hypothalami of postnatal day 7 (PD7) and 3-mo-old (adult) rat offspring. In both PD7 and adult rats, prenatal EtOH exposure was associated with decreased levels of glutathione and increased expression of MnSOD. The concentrations of lipid peroxides and protein carbonyls were normal in PD7 EtOH-exposed offspring, but were increased in adult EtOH-exposed offspring. Both PD7 and adult EtOH-exposed offspring had normal neuropeptide Y and POMC mRNA levels, but the adult offspring had reduced POMC protein concentration. Thus only adult offspring preexposed to EtOH had increased hypothalamic tissue damage and decreased levels of POMC, which could impair melanocortin signaling. We conclude that prenatal EtOH exposure causes hypothalamic oxidative stress, which persists into adult life and alters melanocortin action during adulthood. These neuroendocrine alterations may explain weight gain and insulin resistance in rats exposed to EtOH early in life.
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Affiliation(s)
- Korami Dembele
- Department of Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada R3E3P4
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Kokare DM, Chopde CT, Subhedar NK. Participation of alpha-melanocyte stimulating hormone in ethanol-induced anxiolysis and withdrawal anxiety in rats. Neuropharmacology 2006; 51:536-45. [PMID: 16762375 DOI: 10.1016/j.neuropharm.2006.04.011] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2006] [Revised: 04/01/2006] [Accepted: 04/23/2006] [Indexed: 11/21/2022]
Abstract
Although recent reports underscore a close association between the ethanol consumption and the central melanocortin (MC) system in rats, neurobehavioral component of this association has not been explored. In this study, we investigated the role of alpha-melanocyte stimulating hormone (alpha-MSH) in ethanol (1.5-2 g/kg, i.p.) induced anxiolysis and anxiety-like behavior following withdrawal from prolonged ethanol (9% v/v ethanol, 15 days) consumption, using elevated plus maze (EPM) test in rats. While alpha-MSH (1-5 microg/rat, i.c.v.) showed dose-dependent anxiogenic-like effect, the MC4 receptor antagonist HS014 (1-10 nM/rat, i.c.v.) or antiserum against alpha-MSH (1:500-1:50 dilution, 5 microl/rat, i.c.v.) failed to produce any effect in the EPM test. The anxiolytic-like effect of ethanol was suppressed by central administration of alpha-MSH (0.5 microg/rat, i.c.v.). On the other hand, pretreatment with either HS014 (5 nM/rat, i.c.v.) or antiserum against alpha-MSH (1:100 dilution, 5 microl/rat, i.c.v.) enhanced anxiolytic action of ethanol. Moreover, ethanol withdrawal anxiety was markedly blocked by HS014 (1-10 nM/rat, i.c.v.). These results suggest that alpha-MSH may be implicated in ethanol-induced anxiolysis and withdrawal anxiety. These findings also suggest MC4 receptors as possible therapeutic target for development of drugs to address the ethanol withdrawal-related conditions.
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Affiliation(s)
- Dadasaheb M Kokare
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University Campus, Nagpur 440 033, India
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21
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Murphy KG, Bloom SR. Peripheral influences on central melanocortin neurons. Peptides 2005; 26:1744-52. [PMID: 15970358 DOI: 10.1016/j.peptides.2004.12.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2004] [Accepted: 12/10/2004] [Indexed: 11/21/2022]
Abstract
The melanocortins are peptide products of post-translational processing of the pro-opiomelanocortin precursor protein. Melanocortin-expressing neurons are found in the arcuate nucleus of the hypothalamus and the nucleus of the solitary tract in the brain stem. The central melanocortin system is involved in a number of biological functions, including regulation of energy homeostasis. Hypothalamic and brain stem circuits interpret and integrate a number of peripheral inputs to provide a coordinated central response. This review examines the effect of these peripheral signals on central melanocortin signaling.
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Affiliation(s)
- K G Murphy
- Department of Metabolic Medicine, Imperial College Faculty of Medicine, Hammersmith Campus, Du Cane Road, London W12 ONN, UK
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Navarro M, Cubero I, Chen AS, Chen HY, Knapp DJ, Breese GR, Marsh DJ, Thiele TE. Effects of melanocortin receptor activation and blockade on ethanol intake: a possible role for the melanocortin-4 receptor. Alcohol Clin Exp Res 2005; 29:949-57. [PMID: 15976520 PMCID: PMC1360238 DOI: 10.1097/01.alc.0000167740.19702.8c] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The melanocortin (MC) system is composed of peptides that are cleaved from the polypeptide precursor pro-opiomelanocortin. A growing body of literature suggests that the MC system modulates neurobiological responses to drugs of abuse. Because ethanol has direct effects on central pro-opiomelanocortin activity, it is possible that MC neuropeptides participate in the control of voluntary ethanol consumption. Here we assessed the possibility that MC receptor (MCR) agonists modulate ethanol intake via the MC3 receptor (MC3R) and/or the MC4 receptor (MC4R) and whether the MCR antagonist AgRP-(83-132) controls ethanol consumption. METHODS Mc3r-deficient (Mc3r) and wild-type (Mc3r) littermate mice were given intraperitoneal (10 mg/kg) and intracerebroventricular (1.0 microg ICV) doses of melanotan II (MTII), a nonselective MCR agonist. To assess the role of MC4R, C57BL/6J mice were given an ICV infusion of the highly selective MC4R agonist cyclo(NH-CH2-CH2-CO-His-d-Phe-Arg-Trp-Glu)-NH2 (1.0 or 3.0 microg). Finally, naïve C57BL/6J mice were given an ICV infusion of AgRP-(83-132) (0.05 and 1.0 microg). RESULTS MTII was similarly effective at reducing ethanol drinking in Mc3r-deficient (Mc3r) and wild-type (Mc3r) littermate mice. Furthermore, ICV infusion of the MC4R agonist significantly reduced ethanol drinking, whereas ICV infusion of AgRP-(83-132) significantly increased ethanol drinking in C57BL/6J mice. Neither MTII nor AgRP-(83-132) altered blood ethanol levels at doses that modulated ethanol drinking. CONCLUSIONS The present results suggest that MC4R, and not MC3R, modulates MCR agonist-induced reduction of ethanol consumption and that ethanol intake is increased by the antagonistic actions of AgRP-(83-132). These findings strengthen the argument that MCR signaling controls ethanol consumption and that compounds directed at MCR may represent promising targets for treating alcohol abuse disorders in addition to obesity.
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Affiliation(s)
- Montserrat Navarro
- From the Department of Psychology (TET), Bowles Center for Alcohol Studies (MN, DJK, GRB, TET), Department of Psychiatry (DJK, GRB), and Department of Pharmacology (GRB), University of North Carolina, Chapel Hill, North Carolina; Department of Obesity Research, Merck Research Laboratories, Rahway, New Jersey (ASC, HYC, DJM); and Department of Neurociencia y Ciencias de la Salud, University of Almeria, Spain (MN, IC)
| | - Inmaculada Cubero
- From the Department of Psychology (TET), Bowles Center for Alcohol Studies (MN, DJK, GRB, TET), Department of Psychiatry (DJK, GRB), and Department of Pharmacology (GRB), University of North Carolina, Chapel Hill, North Carolina; Department of Obesity Research, Merck Research Laboratories, Rahway, New Jersey (ASC, HYC, DJM); and Department of Neurociencia y Ciencias de la Salud, University of Almeria, Spain (MN, IC)
| | - Airu S. Chen
- From the Department of Psychology (TET), Bowles Center for Alcohol Studies (MN, DJK, GRB, TET), Department of Psychiatry (DJK, GRB), and Department of Pharmacology (GRB), University of North Carolina, Chapel Hill, North Carolina; Department of Obesity Research, Merck Research Laboratories, Rahway, New Jersey (ASC, HYC, DJM); and Department of Neurociencia y Ciencias de la Salud, University of Almeria, Spain (MN, IC)
| | - Howard Y. Chen
- From the Department of Psychology (TET), Bowles Center for Alcohol Studies (MN, DJK, GRB, TET), Department of Psychiatry (DJK, GRB), and Department of Pharmacology (GRB), University of North Carolina, Chapel Hill, North Carolina; Department of Obesity Research, Merck Research Laboratories, Rahway, New Jersey (ASC, HYC, DJM); and Department of Neurociencia y Ciencias de la Salud, University of Almeria, Spain (MN, IC)
| | - Darin J. Knapp
- From the Department of Psychology (TET), Bowles Center for Alcohol Studies (MN, DJK, GRB, TET), Department of Psychiatry (DJK, GRB), and Department of Pharmacology (GRB), University of North Carolina, Chapel Hill, North Carolina; Department of Obesity Research, Merck Research Laboratories, Rahway, New Jersey (ASC, HYC, DJM); and Department of Neurociencia y Ciencias de la Salud, University of Almeria, Spain (MN, IC)
| | - George R. Breese
- From the Department of Psychology (TET), Bowles Center for Alcohol Studies (MN, DJK, GRB, TET), Department of Psychiatry (DJK, GRB), and Department of Pharmacology (GRB), University of North Carolina, Chapel Hill, North Carolina; Department of Obesity Research, Merck Research Laboratories, Rahway, New Jersey (ASC, HYC, DJM); and Department of Neurociencia y Ciencias de la Salud, University of Almeria, Spain (MN, IC)
| | - Donald J. Marsh
- From the Department of Psychology (TET), Bowles Center for Alcohol Studies (MN, DJK, GRB, TET), Department of Psychiatry (DJK, GRB), and Department of Pharmacology (GRB), University of North Carolina, Chapel Hill, North Carolina; Department of Obesity Research, Merck Research Laboratories, Rahway, New Jersey (ASC, HYC, DJM); and Department of Neurociencia y Ciencias de la Salud, University of Almeria, Spain (MN, IC)
| | - Todd E. Thiele
- From the Department of Psychology (TET), Bowles Center for Alcohol Studies (MN, DJK, GRB, TET), Department of Psychiatry (DJK, GRB), and Department of Pharmacology (GRB), University of North Carolina, Chapel Hill, North Carolina; Department of Obesity Research, Merck Research Laboratories, Rahway, New Jersey (ASC, HYC, DJM); and Department of Neurociencia y Ciencias de la Salud, University of Almeria, Spain (MN, IC)
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Thiele TE, Navarro M, Sparta DR, Fee JR, Knapp DJ, Cubero I. Alcoholism and obesity: overlapping neuropeptide pathways? Neuropeptides 2003; 37:321-37. [PMID: 14698675 DOI: 10.1016/j.npep.2003.10.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Ethanol is a caloric compound, and ethanol drinking and food intake are both appetitive and consummatory behaviors. Furthermore, both ethanol and food have rewarding properties. It is therefore possible that overlapping central pathways are involved with uncontrolled eating and excessive ethanol consumption. A growing list of peptides has been shown to regulate food intake and/or energy homeostasis. Peptides such as the melanocortins, corticotropin releasing factor, and cholecystokinin promote reductions of food intake while others such as galanin and neuropeptide Y stimulate feeding. The present review highlights research aimed at determining if ingestive peptides also regulate voluntary ethanol intake, with an emphasis on the melanocortins and neuropeptide Y. It is suggested that research directed at ingestive peptides may expand our understanding of the neurobiological mechanisms that drive ethanol self-administration, and may reveal new therapeutic candidates for treating alcohol abuse and alcoholism.
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Affiliation(s)
- Todd E Thiele
- Department of Psychology, University of North Carolina at Chapel Hill, Davie Hall, CB# 3270, Chapel Hill, NC 27599-3270, USA.
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