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Begazo-Jimenez R, Yu A, Gros R, Lu WY. Long-Term Supplementation of GABA Regulates Growth, Food Intake, Locomotion, and Lipid Metabolism by Increasing Ghrelin and Growth Hormone in Adolescent Mice. Nutrients 2025; 17:1634. [PMID: 40431374 DOI: 10.3390/nu17101634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2025] [Revised: 05/04/2025] [Accepted: 05/06/2025] [Indexed: 05/29/2025] Open
Abstract
Background/Objectives: The amino acid γ-aminobutyric acid (GABA) is the primary neurotransmitter in the central nervous system (CNS) and acts as an autocrine and/or paracrine signaling molecule in various types of non-neuronal cells. On the other hand, GABA is a nutrient found in a variety of foods and is marketed as a health supplement based on a growing number of studies reporting health benefits in humans and recuperations in animal models of diseases. The present study sought to examine whether supplementation of GABA to young mice regulates their growth as well as glucose and lipid metabolism during physiological adolescence. Methods: Mice were supplemented with GABA over a 16-week period with subsequent anthropometric, metabolic, and endocrine measurements. Results: Results showed that 16-week oral supplementation of GABA increased food consumption and body length while attenuating weight gain in male mice but not females. In addition, GABA treatment lowered the index of body fat (Lee index) and increased the expression of lipolytic enzymes in adipose and liver tissues of male mice without affecting blood glucose levels. Remarkably, supplementation of GABA significantly increased the protein expression of growth hormone (GH) in the pituitary gland of both male and female mice. However, it only substantially increased GH levels in the sera of male mice but not females. Moreover, GABA significantly increased the expression of the GH secretagogue peptide ghrelin in the stomachs of male mice only. Conclusions: Together these novel findings suggest that long-term GABA supplementation fundamentally influences the growth and lipid metabolism of males during adolescent development by stimulating ghrelin-GH production and secretion. The mechanisms of GABA-induced sex-dependent upregulations of ghrelin and GH, as well as lipid metabolism in adolescence, await further studies.
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Affiliation(s)
- Rafael Begazo-Jimenez
- Neuroscience Graduate Program, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A 3K7, Canada
| | - Amelia Yu
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A 3K7, Canada
| | - Robert Gros
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A 3K7, Canada
- Department of Medicine, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A 3K7, Canada
| | - Wei-Yang Lu
- Neuroscience Graduate Program, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A 3K7, Canada
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A 3K7, Canada
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Aranäs C, Caffrey A, Edvardsson CE, Vestlund J, Schmidt HD, Jerlhag E. Synergistic-like decreases in alcohol intake following combined pharmacotherapy with GLP-1 and amylin in male rats. Br J Pharmacol 2025; 182:1292-1305. [PMID: 39622492 DOI: 10.1111/bph.17406] [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: 07/11/2024] [Revised: 10/08/2024] [Accepted: 10/28/2024] [Indexed: 02/11/2025] Open
Abstract
BACKGROUND AND PURPOSE The limited effectiveness of current pharmacological treatments for alcohol use disorder (AUD) highlights the need for novel therapies. These may involve the glucagon-like peptide-1 receptor or the amylin receptor, as treatment with agonists targeting either of these receptors lowers alcohol intake. The complexity of the mechanisms underlying AUD indicates that combining agents could enhance treatment efficacy. While a combination of amylin receptor and GLP-1 receptor agonists reduced food intake and body weight synergistic-like, its influence on alcohol intake is unknown. EXPERIMENTAL APPROACH Effects of a range of dose-combinations of GLP-1 receptor (dulaglutide) and amylin receptor (salmon calcitonin; sCT) agonists on alcohol intake were explored in male and female rats. We used dose combinations that either lowered alcohol intake as monotherapy (0.1 mg·kg-1 + 5 μg·kg-1), or that did not affect alcohol consumption per se (0.075 mg·kg-1 + 2 μg·kg-1). KEY RESULTS Acute administration of dulaglutide and sCT (0.1 mg·kg-1 + 5 μg·kg-1) reduced alcohol intake in males, but not in females. When higher doses were evaluated in female rats, a decrease in alcohol intake was observed. Furthermore, the low dose combination (0.075 mg·kg-1 + 2 μg·kg-1) decreased, in in a synergistic-like manner, alcohol intake and prevented abstinence-induced drinking without affecting kaolin intake in males. However, tolerance developed during sub-chronic treatment. CONCLUSION AND IMPLICATIONS Collectively, these findings show that the combination of dulaglutide and sCT decreased, in in a synergistic-like manner, alcohol consumption in male rats. Contrarily, higher doses are required for females.
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Affiliation(s)
- Cajsa Aranäs
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Antonia Caffrey
- Department of Biobehavioral Health Sciences, School of Nursing, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Christian E Edvardsson
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Jesper Vestlund
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Heath D Schmidt
- Department of Biobehavioral Health Sciences, School of Nursing, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Elisabet Jerlhag
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
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Edwards A, DeSante S, Spencer CD, Hyland L, Smith A, Sankhe AS, Szilvásy-Szabó A, Fekete C, Hill MN, Chee MJ, Abizaid A. Ghrelin Recruits the Endocannabinoid System to Modulate Food Reward. J Neurosci 2025; 45:e1620242024. [PMID: 39779372 PMCID: PMC11867019 DOI: 10.1523/jneurosci.1620-24.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2024] [Revised: 12/05/2024] [Accepted: 12/24/2024] [Indexed: 01/11/2025] Open
Abstract
Ghrelin enhances feeding by activating the growth hormone secretagogue receptor (GHSR). In the brain, GHSRs are expressed in regions responsible for regulating food motivation including the ventral tegmental area (VTA). Endogenous cannabinoids also promote food-seeking behaviors through the cannabinoid receptor-1 (CB-1Rs) in brain regions including the VTA. It is not known, however, if ghrelin and endocannabinoids interact in the VTA to produce these effects. We therefore examined if GHSR and CB-1R interact within the VTA to enhance food motivation. Results show that GHSR and CB-1R mRNA are expressed in the VTA cells in male and female rats and mice, with the GHSR being expressed in dopamine cells and the CB-1R being expressed primarily in nondopaminergic cells with no obvious sex differences. Ghrelin directly activated and increased excitatory tone onto dopamine cells of male and female mice. Male rats lacking fully functional GHSR signaling showed disrupted gene expression of transcripts important for regulating the synthesis, release, and degradation of endocannabinoids and lowered the levels of 2-arachidonoylglycerol (2-AG) within the VTA. Moreover, pharmacological antagonism of VTA CB-1Rs attenuates the orexigenic and appetitive effects of intra-VTA ghrelin in rats and blocks the ability of ghrelin to promote excitatory drive to VTA dopamine neurons. Finally, blocking the breakdown of cannabinoids in the VTA enhances the effects of ghrelin on food motivation. Together, our data show that ghrelin stimulates VTA dopamine cells and ultimately food motivation in part through a mechanism that involves endocannabinoid signaling at the CB-1R.
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Affiliation(s)
- Alexander Edwards
- Neuroscience Department, Carleton University, Ottawa, Ontario K1S5B6, Canada
| | - Stephanie DeSante
- Neuroscience Department, Carleton University, Ottawa, Ontario K1S5B6, Canada
| | - Carl Duncan Spencer
- Neuroscience Department, Carleton University, Ottawa, Ontario K1S5B6, Canada
| | - Lindsay Hyland
- Neuroscience Department, Carleton University, Ottawa, Ontario K1S5B6, Canada
| | - Andrea Smith
- Neuroscience Department, Carleton University, Ottawa, Ontario K1S5B6, Canada
| | - Aditi S Sankhe
- Neuroscience Department, Carleton University, Ottawa, Ontario K1S5B6, Canada
| | - Anett Szilvásy-Szabó
- Laboratory of Integrative Neuroendocrinology, Institute of Experimental Medicine, Budapest H-1083, Hungary
| | - Csaba Fekete
- Laboratory of Integrative Neuroendocrinology, Institute of Experimental Medicine, Budapest H-1083, Hungary
| | - Matthew N Hill
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta T2N4T1, Canada
| | - Melissa J Chee
- Neuroscience Department, Carleton University, Ottawa, Ontario K1S5B6, Canada
| | - Alfonso Abizaid
- Neuroscience Department, Carleton University, Ottawa, Ontario K1S5B6, Canada
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Ayman J, Buzás A, Dochnal R, Palotai M, Jászberényi M, Bagosi Z. Changes in Locomotor Activity Observed During Acute Nicotine Withdrawal Can Be Attenuated by Ghrelin and GHRP-6 in Rats. Biomedicines 2025; 13:143. [PMID: 39857727 PMCID: PMC11761252 DOI: 10.3390/biomedicines13010143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2024] [Revised: 12/31/2024] [Accepted: 01/06/2025] [Indexed: 01/27/2025] Open
Abstract
Background/Objectives: Ghrelin and growth hormone-releasing peptide 6 (GHRP-6) are peptides which can stimulate GH release, acting through the same receptor. Ghrelin and its receptor have been involved in reward sensation and addiction induced by natural and artificial drugs, including nicotine. The present study aimed to investigate the impacts of ghrelin and GHRP-6 on the horizontal and vertical activity in rats exposed to chronic nicotine treatment followed by acute nicotine withdrawal. Methods: Male and female Wistar rats were exposed daily to intraperitoneal (ip) injection with 2 mg/kg nicotine or saline solution for 7 days, twice a day (at 8:00 and at 20:00). In parallel, the rats were exposed daily to an intracerebroventricular (icv) injection with 1 μg/2 μL ghrelin or 1 μg/2 μL GHRP-6 or saline solution for 7 days, once a day (at 8:00). On the morning of the eighth day (12 h after the last ip administration) and the ninth day (24 h after the last ip administration), the horizontal and vertical activity were monitored in a conducta system. Results: On the eighth day, in nicotine-treated rats a significant hyperactivity was observed, that was reduced significantly by ghrelin and GHRP-6. On the ninth day, in nicotine-treated rats a significant hypoactivity was assessed that was reversed significantly by ghrelin and GHRP-6. Conclusions: Based on the present results, the changes in horizontal and vertical activity observed after 12 and 24 h of nicotine withdrawal can be attenuated by ghrelin and GHRP-6.
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Affiliation(s)
- Jázmin Ayman
- Department of Obstetrics and Gynecology, Albert Szent-Györgyi Medical School, University of Szeged, 6725 Szeged, Hungary;
| | - András Buzás
- Department of Surgery, Albert Szent-Györgyi Medical School, University of Szeged, 6725 Szeged, Hungary;
| | - Roberta Dochnal
- Department of Pediatrics and Pedriatic Health Center, Albert Szent-Györgyi Medical School, University of Szeged, 6725 Szeged, Hungary;
| | - Miklós Palotai
- Department of Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA;
| | - Miklós Jászberényi
- Department of Pathophysiology, Albert Szent-Györgyi Medical School, University of Szeged, Szőkefalvi-Nagy Béla str. 6., 6720 Szeged, Hungary;
| | - Zsolt Bagosi
- Department of Pathophysiology, Albert Szent-Györgyi Medical School, University of Szeged, Szőkefalvi-Nagy Béla str. 6., 6720 Szeged, Hungary;
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5
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Mao Q, Wang J, Yang Z, Ding R, Lv S, Ji X. The Pathologic Roles and Therapeutic Implications of Ghrelin/GHSR System in Mental Disorders. Depress Anxiety 2024; 2024:5537319. [PMID: 40226675 PMCID: PMC11919235 DOI: 10.1155/2024/5537319] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 10/16/2024] [Accepted: 10/21/2024] [Indexed: 04/15/2025] Open
Abstract
Ghrelin is a hormone consisting of 28 amino acids. Growth hormone secretagogue receptor (GHSR) is a receptor for ghrelin, which is expressed in the brain, pituitary gland, and adrenal glands, especially in the hypothalamus. The binding of ghrelin to the receptor 1a subtype mediates most of the biological effects of ghrelin. Ghrelin has a close relationship with the onset of psychosis. Ghrelin can affect the onset of psychosis by regulating neurotransmitters such as dopamine, γ-aminobutyric acid (GABA), and 5-hydroxytryptamine (5-HT) through the hypothalamus-pituitary-adrenal (HPA) axis, brain-gut axis, the mesolimbic dopamine system, and other ways. Ghrelin activates neuropeptide Y (NPY) in the hypothalamic arcuate nucleus (ARC) through the GHSR. Ghrelin binds to neurons in the ventral tegmental area (VTA), where it promotes the activity of dopamine neurons in the nucleus accumbens (NAcs) in a GHSR-dependent way, increasing dopamine levels and the reward system. This article summarized the recent research progress of ghrelin in depression, anxiety, schizophrenia, anorexia nervosa (AN), and bulimia nervosa (BN), and emphasized its potential application for psychiatric disorders treatment.
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Affiliation(s)
- Qianshuo Mao
- Henan International Joint Laboratory for Nuclear Protein Regulation, School of Basic Medical Sciences, Henan University, Kaifeng 475004, Henan, China
| | - Jinjia Wang
- Henan International Joint Laboratory for Nuclear Protein Regulation, School of Basic Medical Sciences, Henan University, Kaifeng 475004, Henan, China
| | - Zihan Yang
- Henan International Joint Laboratory for Nuclear Protein Regulation, School of Basic Medical Sciences, Henan University, Kaifeng 475004, Henan, China
| | - Ruidong Ding
- Henan International Joint Laboratory for Nuclear Protein Regulation, School of Basic Medical Sciences, Henan University, Kaifeng 475004, Henan, China
| | - Shuangyu Lv
- Henan International Joint Laboratory for Nuclear Protein Regulation, School of Basic Medical Sciences, Henan University, Kaifeng 475004, Henan, China
- Department of Neurosurgery, The First Affiliated Hospital of Henan University, Henan University, Kaifeng 475001, Henan, China
| | - Xinying Ji
- Faculty of Basic Medical Subjects, Shu-Qing Medical College of Zhengzhou, 6 Gong-Ming Road, Mazhai Town, Erqi District, Zhengzhou 450064, Henan, China
- Department of Medicine, Huaxian County People's Hospital, Huaxian 456400, Henan, China
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6
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Aguggia J, Fernandez G, Cassano D, Mustafá ER, Rodríguez SS, Cantel S, Fehrentz JA, Raingo J, Schiöth HB, Habib AM, De Francesco PN, Perello M. Selective Colocalization of GHSR and GLP-1R in a Subset of Hypothalamic Neurons and Their Functional Interaction. Endocrinology 2024; 166:bqae160. [PMID: 39737802 DOI: 10.1210/endocr/bqae160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2024] [Indexed: 01/01/2025]
Abstract
The GH secretagogue receptor (GHSR) and the glucagon-like peptide-1 receptor (GLP-1R) are G protein-coupled receptors with critical, yet opposite, roles in regulating energy balance. Interestingly, these receptors are expressed in overlapping brain regions. However, the extent to which they target the same neurons and engage in molecular crosstalk remains unclear. To explore the potential colocalization of GHSR and GLP-1R in specific neurons, we performed detailed mapping of cells positive for both receptors using GHSR-eGFP reporter mice or wild-type mice infused with fluorescent ghrelin, alongside an anti-GLP-1R antibody. We found that GHSR+ and GLP-1R+ cells are largely segregated in the mouse brain. The highest overlap was observed in the hypothalamic arcuate nucleus, where 15% to 20% of GHSR+ cells were also GLP-1R+ cells. Additionally, we examined RNA-sequencing datasets from mouse and human brains to assess the fraction and distribution of neurons expressing both receptors, finding that double-positive Ghsr+/Glp1r+ cells are highly segregated, with a small subset of double-positive Ghsr+/Glp1r+ cells representing <10% of all Ghsr+ or Glp1r+ cells, primarily enriched in the hypothalamus. Furthermore, we conducted functional studies using patch-clamp recordings in a heterologous expression system to assess potential crosstalk in regulating presynaptic calcium channels. We provide the first evidence that liraglutide-evoked GLP-1R activity inhibits presynaptic channels, and that the presence of one GPCR attenuates the inhibitory effects of ligand-evoked activity mediated by the other on presynaptic calcium channels. In conclusion, while GHSR and GLP-1R can engage in molecular crosstalk, they are largely segregated across most neuronal types within the brain.
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Affiliation(s)
- Julieta Aguggia
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE; Argentine Research Council (CONICET); Scientific Research Commission, Province of Buenos Aires (CIC-PBA); National University of La Plata], B1906APO La Plata, Buenos Aires, Argentina
| | - Gimena Fernandez
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE; Argentine Research Council (CONICET); Scientific Research Commission, Province of Buenos Aires (CIC-PBA); National University of La Plata], B1906APO La Plata, Buenos Aires, Argentina
| | - Daniela Cassano
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE; Argentine Research Council (CONICET); Scientific Research Commission, Province of Buenos Aires (CIC-PBA); National University of La Plata], B1906APO La Plata, Buenos Aires, Argentina
| | - Emilio R Mustafá
- Laboratory of Electrophysiology, Multidisciplinary Institute of Cell Biology [IMBICE; Argentine Research Council (CONICET); Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], B1906APO La Plata, Buenos Aires, Argentina
| | - Silvia S Rodríguez
- Laboratory of Electrophysiology, Multidisciplinary Institute of Cell Biology [IMBICE; Argentine Research Council (CONICET); Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], B1906APO La Plata, Buenos Aires, Argentina
| | - Sonia Cantel
- Institut des Biomolécules Max Mousseron, University of Montpellier, CNRS, ENSCM, 34293 Montpellier, France
| | - Jean-Alain Fehrentz
- Institut des Biomolécules Max Mousseron, University of Montpellier, CNRS, ENSCM, 34293 Montpellier, France
| | - Jesica Raingo
- Laboratory of Electrophysiology, Multidisciplinary Institute of Cell Biology [IMBICE; Argentine Research Council (CONICET); Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], B1906APO La Plata, Buenos Aires, Argentina
| | - Helgi B Schiöth
- Department of Surgical Sciences, Functional Pharmacology and Neuroscience, University of Uppsala, 751 24 Uppsala, Sweden
| | - Abdella M Habib
- College of Medicine, QU Health, Qatar University, P.O. Box 2713, Doha, Qatar
| | - Pablo N De Francesco
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE; Argentine Research Council (CONICET); Scientific Research Commission, Province of Buenos Aires (CIC-PBA); National University of La Plata], B1906APO La Plata, Buenos Aires, Argentina
| | - Mario Perello
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE; Argentine Research Council (CONICET); Scientific Research Commission, Province of Buenos Aires (CIC-PBA); National University of La Plata], B1906APO La Plata, Buenos Aires, Argentina
- Department of Surgical Sciences, Functional Pharmacology and Neuroscience, University of Uppsala, 751 24 Uppsala, Sweden
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Gomez IM, Uriarte M, Fernandez G, Barrile F, Castrogiovanni D, Cantel S, Fehrentz JA, De Francesco PN, Perello M. Hypothalamic tanycytes internalize ghrelin from the cerebrospinal fluid: Molecular mechanisms and functional implications. Mol Metab 2024; 90:102046. [PMID: 39401613 PMCID: PMC11532763 DOI: 10.1016/j.molmet.2024.102046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2024] [Revised: 10/08/2024] [Accepted: 10/09/2024] [Indexed: 10/22/2024] Open
Abstract
OBJECTIVE The peptide hormone ghrelin exerts potent effects in the brain, where its receptor is highly expressed. Here, we investigated the role of hypothalamic tanycytes in transporting ghrelin across the blood-cerebrospinal fluid (CSF) interface. METHODS We investigated the internalization and transport of fluorescent ghrelin (Fr-ghrelin) in primary cultures of rat hypothalamic tanycytes, mouse hypothalamic explants, and mice. We also tested the impact of inhibiting clathrin-mediated endocytosis of ghrelin in the brain ventricular system on the orexigenic and locomotor effects of the hormone. RESULTS In vitro, we found that Fr-ghrelin is selectively and rapidly internalized at the soma of tanycytes, via a GHSR-independent and clathrin-dependent mechanism, and then transported to the endfoot. In hypothalamic explants, we also found that Fr-ghrelin is internalized at the apical pole of tanycytes. In mice, Fr-ghrelin present in the CSF was rapidly internalized by hypothalamic β-type tanycytes in a clathrin-dependent manner, and pharmacological inhibition of clathrin-mediated endocytosis in the brain ventricular system prolonged the ghrelin-induced locomotor effects. CONCLUSIONS We propose that tanycyte-mediated transport of ghrelin is functionally relevant, as it may contribute to reduce the concentration of this peptide hormone in the CSF and consequently shortens the duration of its central effects.
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Affiliation(s)
- Ivana M Gomez
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], La Plata, Buenos Aires, Argentina
| | - Maia Uriarte
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], La Plata, Buenos Aires, Argentina
| | - Gimena Fernandez
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], La Plata, Buenos Aires, Argentina
| | - Franco Barrile
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], La Plata, Buenos Aires, Argentina
| | - Daniel Castrogiovanni
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], La Plata, Buenos Aires, Argentina
| | - Sonia Cantel
- Institut des Biomolécules Max Mousseron-UMR5247, Pôle Chimie Balard Recherche, Montpellier, France
| | - Jean-Alain Fehrentz
- Institut des Biomolécules Max Mousseron-UMR5247, Pôle Chimie Balard Recherche, Montpellier, France
| | - Pablo N De Francesco
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], La Plata, Buenos Aires, Argentina.
| | - Mario Perello
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], La Plata, Buenos Aires, Argentina; Department of Surgical Sciences, Functional Pharmacology and Neuroscience, University of Uppsala, Uppsala, Sweden.
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8
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Jerlhag E. Ghrelin system and GLP-1 as potential treatment targets for alcohol use disorder. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2024; 178:401-432. [PMID: 39523062 DOI: 10.1016/bs.irn.2024.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2024]
Abstract
Peptides of the gut-brain axis have gained recent attention as potential treatment targets for addiction. While the number of gut-brain peptides is vast, ghrelin and glucagon-like peptide-1 (GLP-1) have been suggested as important players. Ghrelin is traditionally considered an orexigenic peptide, but recent studies found that it increases alcohol intake in rodents and craving for alcohol in humans. Additionally, suppression of the ghrelin receptor attenuates alcohol-related responses in animal models reflecting alcohol use disorder (AUD). For instance, a lower alcohol intake, suppressed motivation to consume alcohol, and attenuated reward from alcohol is observed after ghrelin receptor antagonism treatment. On a similar note, a partial ghrelin receptor agonist prevents hangover symptoms in humans. When it comes to the anorexigenic peptide GLP-1, agonists of its receptor are approved to treat diabetes type 2 and obesity. Extensive preclinical studies have revealed that these GLP-1 receptor agonists reduce alcohol intake, suppress the motivation to consume alcohol, and prevent relapse drink, with effects tentatively associated with a reduced alcohol-induced reward. These preclinical findings have to some extent been varied in humans, as GLP-1 receptor agonists decrease alcohol intake in overweight patients with AUD. Furthermore, genetic variations in either the genes encoding for pre-pro-ghrelin, GHSR, GLP-1, or its receptor, are associated with AUD and heavy alcohol drinking. While central mechanisms appear to modulate the ability of either ghrelin or GLP-1 to regulate alcohol-related responses the exact mechanisms have not been defined. Taken together these preclinical and clinical data imply that gut-brain peptides participate in the addiction process and should be considered as potential targets for AUD treatment.
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Affiliation(s)
- Elisabet Jerlhag
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
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9
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Wu SI, Lee MC, Chen WL, Huang CC. Lacticaseibacillus paracasei PS23 increases ghrelin levels and modulates microbiota composition: a post-hoc analysis of a randomized controlled study. Food Funct 2024; 15:6523-6535. [PMID: 38805370 DOI: 10.1039/d4fo01328j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2024]
Abstract
Muscle damage can occur due to excessive, high-intensity, or inappropriate exercise. It is crucial for athletes and sports enthusiasts to have access to ways that expedite their recovery and alleviate discomfort. Our previous clinical trial demonstrated the anti-inflammatory and muscle damage-ameliorating properties of Lacticaseibacillus paracasei PS23 (PS23), prompting us to further explore the role of this probiotic in muscle damage recovery. This post-hoc analysis of a randomized controlled study investigated potential mediators between the intake of PS23 and the prevention of strength loss after muscle damage. We recruited 105 students from a sports university who had participated in the previously published clinical trial. These participants were randomly allocated to three groups, receiving capsuled live PS23 (L-PS23), heat-treated PS23 (HT-PS23), or a placebo over a period of six weeks. Baseline and endpoint measurements were taken for the levels of circulating ghrelin and other blood markers, stress, mood, quality of life, and the fecal microbiota. A significant increase in ghrelin levels was recorded in the L-PS23 group compared to the other groups. Additionally, both L-PS23 and HT-PS23 interventions led to positive shifts in the gut microbiota composition, particularly in elevated Lacticaseibacillus, Blautia, and Lactobacillus populations. The abundance of these bacteria was positively correlated with exercise performance and inversely correlated with inflammatory markers. In conclusion, dietary supplementation with PS23 may enhance exercise performance and influence muscle damage by increasing ghrelin levels and modulating the gut microbiota composition. Further clarification of the possible mechanisms and clinical implications is required.
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Affiliation(s)
- Shu-I Wu
- Department of Medicine, MacKay Medical College, New Taipei City, Taiwan.
- Section of Psychiatry and Suicide Prevention Center, MacKay Memorial Hospital, Taipei, Taiwan
| | - Mon-Chien Lee
- Graduate Institute of Sports Science, National Taiwan Sport University, Taoyuan City, Taiwan
- Center for General Education, Taipei Medical University, Taipei, Taiwan
| | - Wan-Lin Chen
- Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan
| | - Chi-Chang Huang
- Graduate Institute of Sports Science, National Taiwan Sport University, Taoyuan City, Taiwan
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10
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Lékó AH, Gregory-Flores A, Marchette RCN, Gomez JL, Vendruscolo JCM, Repunte-Canonigo V, Choung V, Deschaine SL, Whiting KE, Jackson SN, Cornejo MP, Perello M, You ZB, Eckhaus M, Rasineni K, Janda KD, Zorman B, Sumazin P, Koob GF, Michaelides M, Sanna PP, Vendruscolo LF, Leggio L. Genetic or pharmacological GHSR blockade has sexually dimorphic effects in rodents on a high-fat diet. Commun Biol 2024; 7:632. [PMID: 38796563 PMCID: PMC11127961 DOI: 10.1038/s42003-024-06303-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 05/08/2024] [Indexed: 05/28/2024] Open
Abstract
The stomach-derived hormone ghrelin regulates essential physiological functions. The ghrelin receptor (GHSR) has ligand-independent actions; therefore, GHSR gene deletion may be a reasonable approach to investigate the role of this system in feeding behaviors and diet-induced obesity (DIO). Here, we investigate the effects of a long-term (12-month) high-fat (HFD) versus regular diet on obesity-related measures in global GHSR-KO and wild-type (WT) Wistar male and female rats. Our main findings are that the GHSR gene deletion protects against DIO and decreases food intake during HFD in male but not in female rats. GHSR gene deletion increases thermogenesis and brain glucose uptake in male rats and modifies the effects of HFD on brain glucose metabolism in a sex-specific manner, as assessed with small animal positron emission tomography. We use RNA-sequencing to show that GHSR-KO rats have upregulated expression of genes responsible for fat oxidation in brown adipose tissue. Central administration of a novel GHSR inverse agonist, PF-5190457, attenuates ghrelin-induced food intake, but only in male, not in female mice. HFD-induced binge-like eating is reduced by inverse agonism in both sexes. Our results support GHSR as a promising target for new pharmacotherapies for obesity.
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Affiliation(s)
- András H Lékó
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Baltimore, MD, USA
- Center on Compulsive Behaviors, Intramural Research Program, National Institutes of Health, Bethesda, MD, USA
| | - Adriana Gregory-Flores
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Baltimore, MD, USA
- Neurobiology of Addiction Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Renata C N Marchette
- Neurobiology of Addiction Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Juan L Gomez
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, Neuroimaging Research Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Janaina C M Vendruscolo
- Neurobiology of Addiction Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Vez Repunte-Canonigo
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Vicky Choung
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Baltimore, MD, USA
- Neurobiology of Addiction Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Sara L Deschaine
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Baltimore, MD, USA
| | - Kimberly E Whiting
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Baltimore, MD, USA
- Neurobiology of Addiction Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Shelley N Jackson
- Translational Analytical Core, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Maria Paula Cornejo
- Grupo de Neurofisiología, Instituto Multidisciplinario de Biología Celular (IMBICE), Universidad Nacional La Plata (UNLP), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) y Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CIC-PBA), La Plata, Argentina
| | - Mario Perello
- Grupo de Neurofisiología, Instituto Multidisciplinario de Biología Celular (IMBICE), Universidad Nacional La Plata (UNLP), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) y Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CIC-PBA), La Plata, Argentina
| | - Zhi-Bing You
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Michael Eckhaus
- Pathology Service, Division of Veterinary Resources, Office of Research Services, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Karuna Rasineni
- Research Service, Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, NE, USA
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
- Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, USA
| | - Kim D Janda
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - Barry Zorman
- Department of Pediatrics, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, USA
| | - Pavel Sumazin
- Department of Pediatrics, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, USA
| | - George F Koob
- Neurobiology of Addiction Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Michael Michaelides
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, Neuroimaging Research Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Pietro P Sanna
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Leandro F Vendruscolo
- Stress and Addiction Neuroscience Unit, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Baltimore, MD, USA.
| | - Lorenzo Leggio
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Baltimore, MD, USA.
- Translational Analytical Core, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, USA.
- Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, School of Public Health, Brown University, Providence, RI, USA.
- Division of Addiction Medicine, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
- Department of Neuroscience, Georgetown University Medical Center, Washington DC, USA.
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11
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Tufvesson-Alm M, Zhang Q, Aranäs C, Blid Sköldheden S, Edvardsson CE, Jerlhag E. Decoding the influence of central LEAP2 on food intake and its effect on accumbal dopamine release. Prog Neurobiol 2024; 236:102615. [PMID: 38641041 DOI: 10.1016/j.pneurobio.2024.102615] [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: 11/09/2023] [Revised: 04/03/2024] [Accepted: 04/16/2024] [Indexed: 04/21/2024]
Abstract
The gut-brain peptide ghrelin and its receptor are established as a regulator of hunger and reward-processing. However, the recently recognized ghrelin receptor inverse agonist, liver-expressed antimicrobial peptide 2 (LEAP2), is less characterized. The present study aimed to elucidate LEAP2s central effect on reward-related behaviors through feeding and its mechanism. LEAP2 was administrated centrally in mice and effectively reduced feeding and intake of palatable foods. Strikingly, LEAP2s effect on feeding was correlated to the preference of the palatable food. Further, LEAP2 reduced the rewarding memory of high preference foods, and attenuated the accumbal dopamine release associated with palatable food exposure and eating. Interestingly, LEAP2 was widely expressed in the brain, and particularly in reward-related brain areas such as the laterodorsal tegmental area (LDTg). This expression was markedly altered when allowed free access to palatable foods. Accordingly, infusion of LEAP2 into LDTg was sufficient to transiently reduce acute palatable food intake. Taken together, the present results show that central LEAP2 has a profound effect on dopaminergic reward signaling associated with food and affects several aspects of feeding. The present study highlights LEAP2s effect on reward, which may have applications for obesity and other reward-related psychiatric and neurological disorders.
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Affiliation(s)
- Maximilian Tufvesson-Alm
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 13A, Gothenburg SE-405 30, Sweden
| | - Qian Zhang
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 13A, Gothenburg SE-405 30, Sweden
| | - Cajsa Aranäs
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 13A, Gothenburg SE-405 30, Sweden
| | - Sebastian Blid Sköldheden
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 13A, Gothenburg SE-405 30, Sweden
| | - Christian E Edvardsson
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 13A, Gothenburg SE-405 30, Sweden
| | - Elisabet Jerlhag
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 13A, Gothenburg SE-405 30, Sweden.
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12
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Söderpalm B, Ericson M. Alcohol and the dopamine system. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2024; 175:21-73. [PMID: 38555117 DOI: 10.1016/bs.irn.2024.02.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/02/2024]
Abstract
The mesolimbic dopamine pathway plays a major role in drug reinforcement and is likely involved also in the development of drug addiction. Ethanol, like most addictive drugs, acutely activates the mesolimbic dopamine system and releases dopamine, and ethanol-associated stimuli also appear to trigger dopamine release. In addition, chronic exposure to ethanol reduces the baseline function of the mesolimbic dopamine system. The molecular mechanisms underlying ethanol´s interaction with this system remain, however, to be unveiled. Here research on the actions of ethanol in the mesolimbic dopamine system, focusing on the involvement of cystein-loop ligand-gated ion channels, opiate receptors, gastric peptides and acetaldehyde is briefly reviewed. In summary, a great complexity as regards ethanol´s mechanism(s) of action along the mesolimbic dopamine system has been revealed. Consequently, several new targets and possibilities for pharmacotherapies for alcohol use disorder have emerged.
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Affiliation(s)
- Bo Söderpalm
- Addiction Biology Unit, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Department of Addiction and Dependency, Sahlgrenska University Hospital, Gothenburg, Sweden.
| | - Mia Ericson
- Addiction Biology Unit, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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13
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Pierce-Messick ZJ, Brink AK, Anna Vo T, Corbit LH. Ghrelin receptor antagonism and satiety attenuate Pavlovian-instrumental transfer. Neurobiol Learn Mem 2024; 207:107864. [PMID: 38000462 DOI: 10.1016/j.nlm.2023.107864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 11/03/2023] [Accepted: 11/20/2023] [Indexed: 11/26/2023]
Abstract
Animals rely on learned cues to guide their behaviour for rewards such as food. The Pavlovian-instrumental transfer (PIT) task can be used to investigate the influence of Pavlovian stimuli on instrumental responding. Ghrelin, an orexigenic peptide, and its receptor, growth hormone secretagogue receptor 1A (GHS-R1A), has received growing interest for its role in reward-motivated learning and behaviours. A significant population of GHS-R1A have been identified within the ventral tegmental area (VTA), a critical node in the mesolimbic reward circuit that is necessary for the expression of PIT. As ghrelin has been found to increase dopaminergic activity in the VTA, we predicted that GHS-R1A antagonism with JMV-2959 would attenuate PIT. Further, given the relationship between hunger levels and changes in ghrelin signalling, we sought to compare the effects GHS-R1A antagonism with those of satiety, hypothesizing parallel effects, with each attenuating PIT. Rats received daily sessions of Pavlovian and then instrumental training over 3 weeks. Across three experiments, we examined the effects of a shift to satiety, or treatment with the GHS-R1A antagonist JMV-2959, either peripherally or directly into the VTA. We found that presentations of a stimulus paired with food reward enhanced responding for food across all conditions, thus demonstrating the expected PIT effect. Further, GHS-R1A antagonism, both peripherally and within the VTA, as well as satiety significantly reduced the magnitude of the PIT effect compared to control conditions. These results clarify our understanding of ghrelin signalling in PIT and begin to elucidate the role of feeding-related peptides in the modulation of reward-related responding.
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14
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So WL, Hu J, Jeffs L, Dempsey H, Lockie SH, Zigman JM, Stark R, Reichenbach A, Andrews ZB. Ghrelin signalling in AgRP neurons links metabolic state to the sensory regulation of AgRP neural activity. Mol Metab 2023; 78:101826. [PMID: 37898450 PMCID: PMC10643323 DOI: 10.1016/j.molmet.2023.101826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 10/11/2023] [Accepted: 10/13/2023] [Indexed: 10/30/2023] Open
Abstract
OBJECTIVE The sensory detection of food and food cues suppresses Agouti related peptide (AgRP) neuronal activity prior to consumption with greatest suppression occurring in response to highly caloric food or interoceptive energy need. However, the interoceptive mechanisms priming an appropriate AgRP neural response to external sensory information of food availability remain unexplored. Since hunger increases plasma ghrelin, we hypothesized that ghrelin receptor (GHSR) signalling on AgRP neurons is a key interoceptive mechanism integrating energy need with external sensory cues predicting caloric availability. METHODS We used in vivo photometry to measure the effects of ghrelin administration or fasting on AgRP neural activity with GCaMP6s and dopamine release in the nucleus accumbens with GRAB-DA in mice lacking ghrelin receptors in AgRP neurons. RESULTS The deletion of GHSR on AgRP neurons prevented ghrelin-induced food intake, motivation and AgRP activity. The presentation of food (peanut butter pellet) or a wooden dowel suppressed AgRP activity in fasted WT but not mice lacking GHSRs in AgRP neurons. Similarly, peanut butter and a wooden dowel increased dopamine release in the nucleus accumbens after ip ghrelin injection in WT but not mice lacking GHSRs in AgRP neurons. No difference in dopamine release was observed in fasted mice. Finally, ip ghrelin administration did not directly increase dopamine neural activity in the ventral tegmental area. CONCLUSIONS Our results suggest that AgRP GHSRs integrate an interoceptive state of energy need with external sensory information to produce an optimal change in AgRP neural activity. Thus, ghrelin signalling on AgRP neurons is more than just a feedback signal to increase AgRP activity during hunger.
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Affiliation(s)
- Wang Lok So
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton 3800, Victoria, Australia
| | - Jiachen Hu
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton 3800, Victoria, Australia
| | - Lotus Jeffs
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton 3800, Victoria, Australia
| | - Harry Dempsey
- The Florey Institute of Neuroscience and Mental Health, Mental Health Division, Parkville, Melbourne, Australia
| | - Sarah H Lockie
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton 3800, Victoria, Australia
| | - Jeffrey M Zigman
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, USA; Division of Endocrinology, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, USA; Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Romana Stark
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton 3800, Victoria, Australia
| | - Alex Reichenbach
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton 3800, Victoria, Australia
| | - Zane B Andrews
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton 3800, Victoria, Australia.
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15
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Ayman J, Palotai M, Dochnal R, Bagosi Z. Ghrelin Amplifies the Nicotine-Induced Release of Dopamine in the Bed Nucleus of Stria Terminalis (BNST). Biomedicines 2023; 11:2456. [PMID: 37760897 PMCID: PMC10525377 DOI: 10.3390/biomedicines11092456] [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: 07/31/2023] [Revised: 09/02/2023] [Accepted: 09/03/2023] [Indexed: 09/29/2023] Open
Abstract
Ghrelin is an orexigenic neuropeptide that is known for stimulating the release of growth hormone (GH) and appetite. In addition, ghrelin has been implicated in addiction to drugs such as nicotine. Nicotine is the principal psychoactive component in tobacco and is responsible for the reward sensation produced by smoking. In our previous in vitro superfusion studies, it was demonstrated that ghrelin and nicotine stimulate equally the dopamine release in the rat amygdala, and ghrelin amplifies the nicotine-induced dopamine release in the rat striatum. However, less attention was paid to the actions of ghrelin and nicotine in the bed nucleus of the stria terminalis (BNST). Therefore, in the present study, nicotine and ghrelin were superfused to the BNST of male Wistar rats, and the dopamine release from the BNST was measured in vitro. In order to determine which receptors mediate these effects, mecamylamine, a non-selective nicotinic acetylcholine receptor (nAchR) antagonist, and GHRP-6, a selective growth hormone secretagogue receptor (GHS-R1A) antagonist, were also superfused to the rat BNST. Nicotine significantly increased the release of dopamine, and this effect was significantly inhibited by mecamylamine. Ghrelin increased dopamine release even more significantly than nicotine did, and this effect was significantly inhibited by GHRP-6. Moreover, when administered together, ghrelin significantly amplified the nicotine-induced release of dopamine in the BNST, and this additive effect was reversed partly by mecamylamine and partly by GHRP-6. Therefore, the present study provides a new base of evidence for the involvement of ghrelin in dopamine signaling implicated in nicotine addiction.
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Affiliation(s)
- Jázmin Ayman
- Department of Obstetrics and Gynecology, Albert Szent-Györgyi School of Medicine, University of Szeged, H-6701 Szeged, Hungary;
| | - Miklós Palotai
- Department of Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA;
| | - Roberta Dochnal
- Department of Pediatrics and Pediatric Health Center, Albert Szent-Györgyi School of Medicine, University of Szeged, H-6701 Szeged, Hungary;
| | - Zsolt Bagosi
- Department of Pathophysiology, Albert Szent-Györgyi School of Medicine, University of Szeged, H-6725 Szeged, Hungary
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16
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Geisler CE, Hayes MR. Metabolic hormone action in the VTA: Reward-directed behavior and mechanistic insights. Physiol Behav 2023; 268:114236. [PMID: 37178855 PMCID: PMC10330780 DOI: 10.1016/j.physbeh.2023.114236] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 04/10/2023] [Accepted: 05/10/2023] [Indexed: 05/15/2023]
Abstract
Dysfunctional signaling in midbrain reward circuits perpetuates diseases characterized by compulsive overconsumption of rewarding substances such as substance abuse, binge eating disorder, and obesity. Ventral tegmental area (VTA) dopaminergic activity serves as an index for how rewarding stimuli are perceived and triggers behaviors necessary to obtain future rewards. The evolutionary linking of reward with seeking and consuming palatable foods ensured an organism's survival, and hormone systems that regulate appetite concomitantly developed to regulate motivated behaviors. Today, these same mechanisms serve to regulate reward-directed behavior around food, drugs, alcohol, and social interactions. Understanding how hormonal regulation of VTA dopaminergic output alters motivated behaviors is essential to leveraging therapeutics that target these hormone systems to treat addiction and disordered eating. This review will outline our current understanding of the mechanisms underlying VTA action of the metabolic hormones ghrelin, glucagon-like peptide-1, amylin, leptin, and insulin to regulate behavior around food and drugs of abuse, highlighting commonalities and differences in how these five hormones ultimately modulate VTA dopamine signaling.
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Affiliation(s)
- Caroline E Geisler
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Matthew R Hayes
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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17
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Burger KS. Food reinforcement architecture: A framework for impulsive and compulsive overeating and food abuse. Obesity (Silver Spring) 2023; 31:1734-1744. [PMID: 37368515 PMCID: PMC10313138 DOI: 10.1002/oby.23792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 03/01/2023] [Accepted: 03/06/2023] [Indexed: 06/29/2023]
Abstract
Few reward-based theories address key drivers of susceptibility to food cues and consumption beyond fullness. Decision-making and habit formation are governed by reinforcement-based learning processes that, when overstimulated, can drive unregulated hedonically motivated overeating. Here, a model food reinforcement architecture is proposed that uses fundamental concepts in reinforcement and decision-making to identify maladaptive eating habits that can lead to obesity. This model is unique in that it identifies metabolic drivers of reward and incorporates neuroscience, computational decision-making, and psychology to map overeating and obesity. Food reinforcement architecture identifies two paths to overeating: a propensity for hedonic targeting of food cues contributing to impulsive overeating and lack of satiation that contributes to compulsive overeating. A combination of those paths will result in a conscious and subconscious drive to overeat independent of negative consequences, leading to food abuse and/or obesity. Use of this model to identify aberrant reinforcement learning processes and decision-making systems that can serve as markers of overeating risk may provide an opportunity for early intervention in obesity.
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Affiliation(s)
- Kyle S Burger
- Department of Nutrition, University of North Carolina, Chapel Hill, North Carolina, USA
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18
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Aranäs C, Edvardsson CE, Shevchouk OT, Zhang Q, Witley S, Blid Sköldheden S, Zentveld L, Vallöf D, Tufvesson-Alm M, Jerlhag E. Semaglutide reduces alcohol intake and relapse-like drinking in male and female rats. EBioMedicine 2023; 93:104642. [PMID: 37295046 PMCID: PMC10363436 DOI: 10.1016/j.ebiom.2023.104642] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/17/2023] [Accepted: 05/22/2023] [Indexed: 06/12/2023] Open
Abstract
BACKGROUND Glucagon-like peptide1 receptor (GLP-1R) agonists have been found to reduce alcohol drinking in rodents and overweight patients with alcohol use disorder (AUD). However, the probability of low semaglutide doses, an agonist with higher potency and affinity for GLP-1R, to attenuate alcohol-related responses in rodents and the underlying neuronal mechanisms is unknown. METHODS In the intermittent access model, we examined the ability of semaglutide to decrease alcohol intake and block relapse-like drinking, as well as imaging the binding of fluorescently marked semaglutide to nucleus accumbens (NAc) in both male and female rats. The suppressive effect of semaglutide on alcohol-induced locomotor stimulation and in vivo dopamine release in NAc was tested in male mice. We evaluated effect of semaglutide on the in vivo release of dopamine metabolites (DOPAC and HVA) and gene expression of enzymes metabolising dopamine (MAOA and COMT) in male mice. FINDINGS In male and female rats, acute and repeated semaglutide administration reduced alcohol intake and prevented relapse-like drinking. Moreover, fluorescently labelled semaglutide was detected in NAc of alcohol-drinking male and female rats. Further, semaglutide attenuated the ability of alcohol to cause hyperlocomotion and to elevate dopamine in NAc in male mice. As further shown in male mice, semaglutide enhanced DOPAC and HVA in NAc when alcohol was onboard and increased the gene expression of COMT and MAOA. INTERPRETATION Altogether, this indicates that semaglutide reduces alcohol drinking behaviours, possibly via a reduction in alcohol-induced reward and NAc dependent mechanisms. As semaglutide also decreased body weight of alcohol-drinking rats of both sexes, upcoming clinical studies should test the plausibility that semaglutide reduces alcohol intake and body weight in overweight AUD patients. FUNDING Swedish Research Council (2019-01676), LUA/ALF (723941) from the Sahlgrenska University Hospital and the Swedish brain foundation.
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Affiliation(s)
- Cajsa Aranäs
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Christian E Edvardsson
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Olesya T Shevchouk
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Qian Zhang
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Sarah Witley
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Sebastian Blid Sköldheden
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Lindsay Zentveld
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Daniel Vallöf
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Maximilian Tufvesson-Alm
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Elisabet Jerlhag
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
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How gut hormones shape reward: A systematic review of the role of ghrelin and GLP-1 in human fMRI. Physiol Behav 2023; 263:114111. [PMID: 36740132 DOI: 10.1016/j.physbeh.2023.114111] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/27/2023] [Accepted: 02/01/2023] [Indexed: 02/05/2023]
Abstract
The gastrointestinal hormones ghrelin and glucagon-like peptide-1 (GLP-1) have opposite secretion patterns, as well as opposite effects on metabolism and food intake. Beyond their role in energy homeostasis, gastrointestinal hormones have also been suggested to modulate the reward system. However, the potential of ghrelin and GLP-1 to modulate reward responses in humans has not been systematically reviewed before. To evaluate the convergence of published results, we first conduct a multi-level kernel density meta-analysis of studies reporting a positive association of ghrelin (Ncomb = 353, 18 contrasts) and a negative association of GLP-1 (Ncomb = 258, 12 contrasts) and reward responses measured using task functional magnetic resonance imaging (fMRI). Second, we complement the meta-analysis using a systematic literature review, focusing on distinct reward phases and applications in clinical populations that may account for variability across studies. In line with preclinical research, we find that ghrelin increases reward responses across studies in key nodes of the motivational circuit, such as the nucleus accumbens, pallidum, putamen, substantia nigra, ventral tegmental area, and the dorsal mid insula. In contrast, for GLP-1, we did not find sufficient convergence in support of reduced reward responses. Instead, our systematic review identifies potential differences of GLP-1 on anticipatory versus consummatory reward responses. Based on a systematic synthesis of available findings, we conclude that there is considerable support for the neuromodulatory potential of gut-based circulating peptides on reward responses. To unlock their potential for clinical applications, it may be useful for future studies to move beyond anticipated rewards to cover other reward facets.
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Ghrelin/GHS-R1A antagonism in memory test and its effects on central molecular signaling involved in addiction in rats. Pharmacol Biochem Behav 2023; 224:173528. [PMID: 36870422 DOI: 10.1016/j.pbb.2023.173528] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Revised: 12/23/2022] [Accepted: 02/12/2023] [Indexed: 03/06/2023]
Abstract
Central ghrelin signaling seems to play important role in addiction as well as memory processing. Antagonism of the growth hormone secretagogue receptor (GHS-R1A) has been recently proposed as a promising tool for the unsatisfactory drug addiction therapy. However, molecular aspects of GHS-R1A involvement in specific brain regions remain unclear. The present study demonstrated for the first time that acute as well as subchronic (4 days) administration of the experimental GHS-R1A antagonist JMV2959 in usual intraperitoneal doses including 3 mg/kg, had no influence on memory functions tested in the Morris Water Maze in rats as well as no significant effects on the molecular markers linked with memory processing in selected brain areas in rats, specifically on the β-actin, c-Fos, two forms of the calcium/calmodulin-dependent protein kinase II (CaMKII, p-CaMKII) and the cAMP-response element binding protein (CREB, p-CREB), within the medial prefrontal cortex (mPFC), nucleus accumbens (NAc), dorsal striatum, and hippocampus (HIPP). Furthermore, following the methamphetamine intravenous self-administration in rats, the 3 mg/kg JMV2959 pretreatment significantly reduced or prevented the methamphetamine-induced significant decrease of hippocampal β-actin and c-Fos as well as it prevented the significant decrease of CREB in the NAC and mPFC. These results imply, that the GHS-R1A antagonist/JMV2959 might reduce/prevent some of the memory-linked molecular changes elicited by methamphetamine addiction within brain structures associated with memory (HIPP), reward (NAc), and motivation (mPFC), which may contribute to the previously observed significant JMV2959-induced reduction of the methamphetamine self-administration and drug-seeking behavior in the same animals. Further research is necessary to corroborate these results.
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Impaired Ghrelin Signaling Does Not Lead to Alterations of Anxiety-like Behaviors in Adult Mice Chronically Exposed to THC during Adolescence. Biomedicines 2023; 11:biomedicines11010144. [PMID: 36672651 PMCID: PMC9855766 DOI: 10.3390/biomedicines11010144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 12/17/2022] [Accepted: 01/04/2023] [Indexed: 01/09/2023] Open
Abstract
As marijuana use during adolescence has been increasing, the need to understand the effects of its long-term use becomes crucial. Previous research suggested that marijuana consumption during adolescence increases the risk of developing mental illnesses, such as schizophrenia, depression, and anxiety. Ghrelin is a peptide produced primarily in the gut and is important for feeding behavior. Recent studies have shown that ghrelin and its receptor, the growth hormone secretagogue receptor (GHSR), play important roles in mediating stress, as well as anxiety and depression-like behaviors in animal models. Here, we investigated the effects of chronic tetrahydrocannabinol (THC) administration during late adolescence (P42-55) in GHSR (GHSR -/-) knockout mice and their wild-type littermates in relation to anxiety-like behaviors. We determined that continuous THC exposure during late adolescence did not lead to any significant alterations in the anxiety-like behaviors of adult mice, regardless of genotype, following a prolonged period of no exposure (1 month). These data indicate that in the presence of intact or impaired ghrelin/GHSR signaling, THC exposure during late adolescence has limited if any long-term impact on anxiety-like behaviors in mice.
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Jerlhag E. Animal studies reveal that the ghrelin pathway regulates alcohol-mediated responses. Front Psychiatry 2023; 14:1050973. [PMID: 36970276 PMCID: PMC10030715 DOI: 10.3389/fpsyt.2023.1050973] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 02/21/2023] [Indexed: 03/29/2023] Open
Abstract
Alcohol use disorder (AUD) is often described as repeated phases of binge drinking, compulsive alcohol-taking, craving for alcohol during withdrawal, and drinking with an aim to a reduce the negative consequences. Although multifaceted, alcohol-induced reward is one aspect influencing the former three of these. The neurobiological mechanisms regulating AUD processes are complex and one of these systems is the gut-brain peptide ghrelin. The vast physiological properties of ghrelin are mediated via growth hormone secretagogue receptor (GHSR, ghrelin receptor). Ghrelin is well known for its ability to control feeding, hunger, and metabolism. Moreover, ghrelin signaling appears central for alcohol-mediated responses; findings reviewed herein. In male rodents GHSR antagonism reduces alcohol consumption, prevents relapse drinking, and attenuates the motivation to consume alcohol. On the other hand, ghrelin increases the consumption of alcohol. This ghrelin-alcohol interaction is also verified to some extent in humans with high alcohol consumption. In addition, either pharmacological or genetic suppression of GHSR decreases several alcohol-related effects (behavioral or neurochemical). Indeed, this suppression blocks the alcohol-induced hyperlocomotion and dopamine release in nucleus accumbens as well as ablates the alcohol reward in the conditioned place preference model. Although not fully elucidated, this interaction appears to involve areas central for reward, such as the ventral tegmental area (VTA) and brain nodes targeted by VTA projections. As reviewed briefly, the ghrelin pathway does not only modulate alcohol-mediated effects, it regulates reward-related behaviors induced by addictive drugs. Although personality traits like impulsivity and risk-taking behaviors are common in patients with AUD, the role of the ghrelin pathway thereof is unknown and remains to be studied. In summary, the ghrelin pathway regulates addiction processes like AUD and therefore the possibility that GHSR antagonism reduces alcohol or drug-taking should be explored in randomized clinical trials.
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Ercan S, Basaranlar G. Effects of ghrelin on sulfite induced changes in lipid peroxidation, spatial memory, and locomotor activity in rats. Neurol Res 2022; 45:423-428. [PMID: 36449323 DOI: 10.1080/01616412.2022.2149535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
BACKGROUND Humans are constantly exposed to sulfites and their derivatives, both endogenously and exogenously. Recent studies have shown that sulfite and its derivatives can cause oxidative stress. . Ghrelin has been reported to possess antioxidant properties and stimulates neurogenesis in hippocampal progenitor cells. This study aimed to investigate the effects of ghrelin on sulfite-induced changes in hippocampal oxidative status, spatial learning and locomotor activity in rats. METHODS Forty male albino Wistar rats were randomized into four groups as follows; Group 1: Control (C); Group 2: Sodium metabisulfite (Na2S2O5) treated (S); Group 3: Ghrelin treated (G); Group 4: Na2S2O5 + Ghrelin treated (SG). Sodium metabisulfite (100 mg/kg/day) was given by gastric gavage, and ghrelin (20 µg/kg/day) was administered intraperitoneally for 5 weeks. Thiobarbituric acid reactive substances (TBARS) were measured through fluorometric method. The spatial memory and locomotor activity of the rats were evaluated by Y-maze test. RESULTS Y-maze results revealed an enhancement of short-term spatial learning and memory in S and SG groups compared to C group. TBARS levels were increased significantly in S group with respect to C group. The increase in TBARS levels induced by sulfite was completely prevented by ghrelin in SG group. CONCLUSION We suggest that systemic ghrelin administration might ameliorate ingested sodium metabisulfite-induced hippocampal oxidative damage without providing any changes in spatial learning, memory and locomotion. Further investigation concerning the mechanism of ghrelin action in hippocampus might provide valuable information for developing new therapeutic approaches to attenuate oxidative stress in hippocampal tissue.
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Affiliation(s)
- Sevim Ercan
- Vocational School of Health Services, Akdeniz University, Antalya, Turkey
| | - Goksun Basaranlar
- Vocational School of Health Services, Biomedical Device Technology, Izmir Democracy University, İzmir, Turkey
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Goral RO, Harper KM, Bernstein BJ, Fry SA, Lamb PW, Moy SS, Cushman JD, Yakel JL. Loss of GABA co-transmission from cholinergic neurons impairs behaviors related to hippocampal, striatal, and medial prefrontal cortex functions. Front Behav Neurosci 2022; 16:1067409. [PMID: 36505727 PMCID: PMC9730538 DOI: 10.3389/fnbeh.2022.1067409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 11/04/2022] [Indexed: 11/25/2022] Open
Abstract
Introduction: Altered signaling or function of acetylcholine (ACh) has been reported in various neurological diseases, including Alzheimer's disease, Tourette syndrome, epilepsy among others. Many neurons that release ACh also co-transmit the neurotransmitter gamma-aminobutyrate (GABA) at synapses in the hippocampus, striatum, substantia nigra, and medial prefrontal cortex (mPFC). Although ACh transmission is crucial for higher brain functions such as learning and memory, the role of co-transmitted GABA from ACh neurons in brain function remains unknown. Thus, the overarching goal of this study was to investigate how a systemic loss of GABA co-transmission from ACh neurons affected the behavioral performance of mice. Methods: To do this, we used a conditional knock-out mouse of the vesicular GABA transporter (vGAT) crossed with the ChAT-Cre driver line to selectively ablate GABA co-transmission at ACh synapses. In a comprehensive series of standardized behavioral assays, we compared Cre-negative control mice with Cre-positive vGAT knock-out mice of both sexes. Results: Loss of GABA co-transmission from ACh neurons did not disrupt the animal's sociability, motor skills or sensation. However, in the absence of GABA co-transmission, we found significant alterations in social, spatial and fear memory as well as a reduced reliance on striatum-dependent response strategies in a T-maze. In addition, male conditional knockout (CKO) mice showed increased locomotion. Discussion: Taken together, the loss of GABA co-transmission leads to deficits in higher brain functions and behaviors. Therefore, we propose that ACh/GABA co-transmission modulates neural circuitry involved in the affected behaviors.
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Affiliation(s)
- R. Oliver Goral
- Neurobiology Laboratory, Department of Health and Human Services, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, United States,Center on Compulsive Behaviors, National Institutes of Health, Bethesda, MD, United States
| | - Kathryn M. Harper
- Department of Psychiatry and Carolina Institute for Developmental Disabilities, University of North Carolina, Chapel Hill, NC, United States
| | - Briana J. Bernstein
- Neurobiology Laboratory, Department of Health and Human Services, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, United States,Department of Health and Human Services, Neurobehavioral Core, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, United States
| | - Sydney A. Fry
- Neurobiology Laboratory, Department of Health and Human Services, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, United States,Department of Health and Human Services, Neurobehavioral Core, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, United States
| | - Patricia W. Lamb
- Neurobiology Laboratory, Department of Health and Human Services, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, United States
| | - Sheryl S. Moy
- Department of Psychiatry and Carolina Institute for Developmental Disabilities, University of North Carolina, Chapel Hill, NC, United States
| | - Jesse D. Cushman
- Neurobiology Laboratory, Department of Health and Human Services, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, United States,Department of Health and Human Services, Neurobehavioral Core, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, United States
| | - Jerrel L. Yakel
- Neurobiology Laboratory, Department of Health and Human Services, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, United States,*Correspondence: Jerrel L. Yakel
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Reich N, Hölscher C. Beyond Appetite: Acylated Ghrelin As A Learning, Memory and Fear Behavior-modulating Hormone. Neurosci Biobehav Rev 2022; 143:104952. [DOI: 10.1016/j.neubiorev.2022.104952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 04/27/2022] [Accepted: 11/05/2022] [Indexed: 11/10/2022]
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O'Connor RM, Kenny PJ. Utility of 'substance use disorder' as a heuristic for understanding overeating and obesity. Prog Neuropsychopharmacol Biol Psychiatry 2022; 118:110580. [PMID: 35636576 DOI: 10.1016/j.pnpbp.2022.110580] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/24/2022] [Accepted: 05/24/2022] [Indexed: 02/07/2023]
Abstract
Rates of obesity and obesity-associated diseases have increased dramatically in countries with developed economies. Substance use disorders (SUDs) are characterized by the persistent use of the substance despite negative consequences. It has been hypothesized that overconsumption of palatable energy dense food can elicit SUD-like maladaptive behaviors that contribute to persistent caloric intake beyond homeostatic need even in the face of negative consequences. Palatable food and drugs of abuse act on many of the same motivation-related circuits in the brain, and can induce, at least superficially, similar molecular, cellular, and physiological adaptations on these circuits. As such, applying knowledge about the neurobiological mechanisms of SUDs may serve as useful heuristic to better understand the persistent overconsumption of palatable food that contributes to obesity. However, many important differences exist between the actions of drugs of abuse and palatable food in the brain. This warrants caution when attributing weight gain and obesity to the manifestation of a putative SUD-related behavioral disorder. Here, we describe similarities and differences between compulsive drug use in SUDs and overconsumption in obesity and consider the merit of the concept of "food addiction".
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Affiliation(s)
- Richard M O'Connor
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, United States of America
| | - Paul J Kenny
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, United States of America.
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Orellana E, Horvath N, Farokhnia M, Leggio L, Hajnal A. Changes in Plasma Ghrelin Levels Following Surgical and Non-Surgical Weight-Loss in Female Rats Predict Alcohol Use. Brain Res Bull 2022; 188:179-186. [PMID: 35901985 DOI: 10.1016/j.brainresbull.2022.07.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 07/20/2022] [Accepted: 07/24/2022] [Indexed: 11/02/2022]
Abstract
The weight-loss surgery Roux-en Y gastric bypass (RYGB) is a relatively effective, long-term treatment option for patients with morbid obesity. However, accumulating clinical evidence suggests that patients receiving RYGB may be at increased risk of developing alcohol use disorder. This observation has been repeatedly supported by preclinical studies showing rodents increase intake of ethanol (EtOH) after RYGB, and has been further confirmed by human studies. A promising alternative to RYGB is sleeve gastrectomy (SG), which has resulted in decreased EtOH consumption in some rodent studies. The exact mechanism underlying the differential alcohol outcomes after RYGB versus SG has yet to be elucidated. However, the gut hormone ghrelin has emerged as a potential candidate from previous preclinical studies specific to RYGB surgeries and due to its action to stimulate food and alcohol intake and cravings. To directly assess changes in plasma ghrelin levels following weigh loss surgeries in the context of alcohol intake, 24 female rats were separated into three surgical groups receiving RYGB, SG, or Sham surgery followed by caloric restriction to produce adiposity matched controls (Sham-AM). Blood was drawn for fasted and fed plasma ghrelin (acyl and des-acyl) assays at multiple time points: while on a normal diet (ND), after 5-week exposure to a high fat diet (HFD), following surgery, and after a series of two-bottle alcohol choice test with increasing concentrations (2%, 4%, 6%, 8%) of EtOH. Consistent with previous observations, RYGB rats drank more EtOH than SG rats across all concentrations. As expected, fasted ghrelin levels were blunted after HFD feeding, compared to normal diet baseline. After RYGB, fasted ghrelin levels returned to higher levels while remained blunted after SG and Sham-AM. Fed acyl ghrelin levels were significantly increased to above "normal" levels after RYGB, but remain low after SG and Sham-AM. Given that post-RYGB acyl ghrelin levels are raised to a fasted state regardless of actual prandial status, we conclude that RYGB may results in a hormonal state reminiscence of a fasted state with the inability of feeding to inhibit ghrelin production, an effect which could potentially contribute to increased EtOH intake following the surgery. In contrast, following SG, ghrelin levels in rats remain consistent with the fed state regardless of prandial status, potentially explaining lower alcohol intake and lower risk of developing AUD.
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Affiliation(s)
- Elise Orellana
- The Pennsylvania State University College of Medicine, Department of Neural and Behavioral Sciences.
| | - Nelli Horvath
- The Pennsylvania State University College of Medicine, Department of Neural and Behavioral Sciences
| | - Mehdi Farokhnia
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, Baltimore and Bethesda, Maryland, USA
| | - Lorenzo Leggio
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, Baltimore and Bethesda, Maryland, USA
| | - Andras Hajnal
- The Pennsylvania State University College of Medicine, Department of Neural and Behavioral Sciences
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Prins K, Huisman M, McLuskey A, Mies R, Karels B, Delhanty PJD, Visser JA. Ghrelin deficiency sex-dependently affects food intake, locomotor activity, and adipose and hepatic gene expression in a binge-eating mouse model. Am J Physiol Endocrinol Metab 2022; 322:E494-E507. [PMID: 35403437 DOI: 10.1152/ajpendo.00432.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Binge-eating disorder is the most prevalent eating disorder diagnosed, affecting three times more women than men. Ghrelin stimulates appetite and reward signaling, and loss of its receptor reduces binge-eating behavior in male mice. Here, we examined the influence of ghrelin itself on binge-eating behavior in both male and female mice. Five-wk-old wild-type (WT) and ghrelin-deficient (Ghrl-/-) mice were housed individually in indirect calorimetry cages for 9 wks. Binge-like eating was induced by giving mice ad libitum chow, but time-restricted access to a Western-style diet (WD; 2 h access, 3 days/wk) in the light phase (BE); control groups received ad libitum chow (CO), or ad libitum access to both diets (CW). All groups of BE mice showed binge-eating behavior, eating up to 60% of their 24-h intake during the WD access period. Subsequent dark phase chow intake was decreased in Ghrl-/- mice and remained decreased in Ghrl-/- females on nonbinge days. Also, nonbinge day locomotor activity was lower in Ghrl-/- than in WT BE females. Upon euthanasia, Ghrl-/- BE mice weighed less and had a lower lean body mass percentage than WT BE mice. In BE and CW groups, ghrelin and sex altered the expression of genes involved in lipid processing, thermogenesis, and aging in white adipose tissue and livers. We conclude that, although ghrelin deficiency does not hamper the development of binge-like eating, it sex-dependently alters food intake timing, locomotor activity, and metabolism. These results add to the growing body of evidence that ghrelin signaling is sexually dimorphic.NEW & NOTEWORTHY Ghrelin, a peptide hormone secreted from the gut, is involved in hunger and reward signaling, which are altered in binge-eating disorder. Although sex differences have been described in both binge-eating and ghrelin signaling, this interaction has not been fully elucidated. Here, we show that ghrelin deficiency affects the behavior and metabolism of mice in a binge-like eating paradigm, and that the sex of the mice impacts the magnitude and direction of these effects.
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Affiliation(s)
- Karina Prins
- Department of Internal Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Martin Huisman
- Department of Internal Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Anke McLuskey
- Department of Internal Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Rosinda Mies
- Department of Internal Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Bas Karels
- Department of Internal Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Patric J D Delhanty
- Department of Internal Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Jenny A Visser
- Department of Internal Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
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Wellman M, Budin R, Woodside B, Abizaid A. Energetic demands of lactation produce an increase in the expression of growth hormone secretagogue receptor in the hypothalamus and ventral tegmental area of the rat despite a reduction in circulating ghrelin. J Neuroendocrinol 2022; 34:e13126. [PMID: 35365872 DOI: 10.1111/jne.13126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 01/07/2022] [Accepted: 02/08/2022] [Indexed: 12/26/2022]
Abstract
Lactating rats show changes in the secretion of hormones and brain signals that promote hyperphagia and facilitate the production of milk. Little is known, however, about the role of ghrelin in the mechanisms sustaining lactational hyperphagia. Here, we used Wistar female rats that underwent surgery to sever the galactophores to prevent milk delivery (GC rats) and decrease the energetic drain of milk delivery. We compared plasma acyl-ghrelin concentrations and growth hormone secretagogue receptor (GHSR) mRNA expression in different brain regions of GC rats with those of sham operated lactating and nonlactating rats. Additional lactating and nonlactating rats were implanted with cannulae aimed at the lateral ventricles and were used to compare feeding responses to central ghrelin or GHSR antagonist infusions to those of nonlactating rats receiving similar infusions on day 14-16 postpartum (pp). Results show lower plasma acyl-ghrelin concentrations on day 15 pp sham operated lactating rats compared to GC or nonlactating rats. These changes occur in association with increased GHSR mRNA expression in the hypothalamic arcuate nucleus (ARC) and ventral tegmental area (VTA) of sham operated lactating rats. Despite lactational hyperphagia, infusions of ghrelin (0.25 or 1 μg) resulted in similar increases in food intake in lactating and nonlactating rats. In addition, infusions of the GHSR antagonist JMV3002 (4 μg in 1 μl of vehicle) produced greater suppression of food intake in lactating rats than in nonlactating rats. These data suggest that, despite lower plasma ghrelin, the energetic drain of lactation increases sensitivity to the orexigenic effects of ghrelin in brain regions important for food intake and energy balance, and these events are associated with lactational hyperphagia.
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Affiliation(s)
- Martin Wellman
- Neuroscience Department, Carleton University, Ottawa, Ontario, Canada
| | - Radek Budin
- Centre for Studies in Behavioural Neurobiology, Psychology Department, Concordia University, Montreal, Quebec, Canada
| | - Barbara Woodside
- Centre for Studies in Behavioural Neurobiology, Psychology Department, Concordia University, Montreal, Quebec, Canada
| | - Alfonso Abizaid
- Neuroscience Department, Carleton University, Ottawa, Ontario, Canada
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30
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Gupta S, Mukhopadhyay S, Mitra A. Therapeutic potential of GHSR-1A antagonism in alcohol dependence, a review. Life Sci 2022; 291:120316. [PMID: 35016882 DOI: 10.1016/j.lfs.2022.120316] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 01/05/2022] [Accepted: 01/05/2022] [Indexed: 11/28/2022]
Abstract
Growth hormone secretagogue receptor type 1A (GHSR-1A) is a functional receptor of orexigenic peptide ghrelin and is highly expressed in mesolimbic dopaminergic systems that regulate incentive value of artificial reward in substance abuse. Interestingly, GHSR-1A has also shown ligand-independent constitutive activity. Alcohol use disorder (AUD) is one of the growing concerns worldwide as it involves complex neuro-psycho-endocrinological interactions. Positive correlation of acylated ghrelin and alcohol-induced human brain response in the right and left ventral striatum are evident. In the last decade, the beneficial effects of ghrelin receptor (GHSR-1A) antagonism to suppress artificial reward circuitries and induce self-control for alcohol consumption have drawn significant attention from researchers. In this updated review, we summarize the available recent preclinical, clinical, and experimental data to discuss functional, molecular actions of central ghrelin-GHSR-1A signaling in different craving levels for alcohol as well as to promote "GHSR-1A antagonism" as one of the potential therapies in early abstinence.
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Affiliation(s)
- Shreyasi Gupta
- Department of Zoology, Triveni Devi Bhalotia College, Raniganj, Paschim Bardhaman 713 347, West Bengal, India
| | - Sanchari Mukhopadhyay
- Department of Psychiatry, National Institute of Mental Health and Neurosciences, Hombegowda Nagar, Bengaluru 560029, India
| | - Arkadeep Mitra
- Department of Zoology, City College, 102/1, Raja Rammohan Sarani, Kolkata 700 009, West Bengal, India.
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Sustkova-Fiserova M, Charalambous C, Khryakova A, Certilina A, Lapka M, Šlamberová R. The Role of Ghrelin/GHS-R1A Signaling in Nonalcohol Drug Addictions. Int J Mol Sci 2022; 23:761. [PMID: 35054944 PMCID: PMC8776007 DOI: 10.3390/ijms23020761] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/05/2022] [Accepted: 01/06/2022] [Indexed: 01/27/2023] Open
Abstract
Drug addiction causes constant serious health, social, and economic burden within the human society. The current drug dependence pharmacotherapies, particularly relapse prevention, remain limited, unsatisfactory, unreliable for opioids and tobacco, and even symptomatic for stimulants and cannabinoids, thus, new more effective treatment strategies are researched. The antagonism of the growth hormone secretagogue receptor type A (GHS-R1A) has been recently proposed as a novel alcohol addiction treatment strategy, and it has been intensively studied in experimental models of other addictive drugs, such as nicotine, stimulants, opioids and cannabinoids. The role of ghrelin signaling in these drugs effects has also been investigated. The present review aims to provide a comprehensive overview of preclinical and clinical studies focused on ghrelin's/GHS-R1A possible involvement in these nonalcohol addictive drugs reinforcing effects and addiction. Although the investigation is still in its early stage, majority of the existing reviewed experimental results from rodents with the addition of few human studies, that searched correlations between the genetic variations of the ghrelin signaling or the ghrelin blood content with the addictive drugs effects, have indicated the importance of the ghrelin's/GHS-R1As involvement in the nonalcohol abused drugs pro-addictive effects. Further research is necessary to elucidate the exact involved mechanisms and to verify the future potential utilization and safety of the GHS-R1A antagonism use for these drug addiction therapies, particularly for reducing the risk of relapse.
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Affiliation(s)
- Magdalena Sustkova-Fiserova
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 100 00 Prague, Czech Republic; (C.C.); (A.K.); (A.C.); (M.L.)
| | - Chrysostomos Charalambous
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 100 00 Prague, Czech Republic; (C.C.); (A.K.); (A.C.); (M.L.)
| | - Anna Khryakova
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 100 00 Prague, Czech Republic; (C.C.); (A.K.); (A.C.); (M.L.)
| | - Alina Certilina
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 100 00 Prague, Czech Republic; (C.C.); (A.K.); (A.C.); (M.L.)
| | - Marek Lapka
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 100 00 Prague, Czech Republic; (C.C.); (A.K.); (A.C.); (M.L.)
| | - Romana Šlamberová
- Department of Physiology, Third Faculty of Medicine, Charles University, Ke Karlovu 4, 120 00 Prague, Czech Republic;
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Tufvesson-Alm M, Shevchouk OT, Jerlhag E. Insight into the role of the gut-brain axis in alcohol-related responses: Emphasis on GLP-1, amylin, and ghrelin. Front Psychiatry 2022; 13:1092828. [PMID: 36699502 PMCID: PMC9868418 DOI: 10.3389/fpsyt.2022.1092828] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 12/15/2022] [Indexed: 01/11/2023] Open
Abstract
Alcohol use disorder (AUD) contributes substantially to global morbidity and mortality. Given the heterogenicity of this brain disease, available pharmacological treatments only display efficacy in sub-set of individuals. The need for additional treatment options is thus substantial and is the goal of preclinical studies unraveling neurobiological mechanisms underlying AUD. Although these neurobiological processes are complex and numerous, one system gaining recent attention is the gut-brain axis. Peptides of the gut-brain axis include anorexigenic peptide like glucagon-like peptide-1 (GLP-1) and amylin as well as the orexigenic peptide ghrelin. In animal models, agonists of the GLP-1 or amylin receptor and ghrelin receptor (GHSR) antagonists reduce alcohol drinking, relapse drinking, and alcohol-seeking. Moreover, these three gut-brain peptides modulate alcohol-related responses (behavioral and neurochemical) in rodents, suggesting that the alcohol reduction may involve a suppression of alcohol's rewarding properties. Brain areas participating in the ability of these gut-brain peptides to reduce alcohol-mediated behaviors/neurochemistry involve those important for reward. Human studies support these preclinical studies as polymorphisms of the genes encoding for GLP-1 receptor or the ghrelin pathway are associated with AUD. Moreover, a GLP-1 receptor agonist decreases alcohol drinking in overweight patients with AUD and an inverse GHSR agonist reduces alcohol craving. Although preclinical and clinical studies reveal an interaction between the gut-brain axis and AUD, additional studies should explore this in more detail.
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Affiliation(s)
- Maximilian Tufvesson-Alm
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Olesya T Shevchouk
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Elisabet Jerlhag
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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Deschaine SL, Farokhnia M, Gregory-Flores A, Zallar LJ, You ZB, Sun H, Harvey DM, Marchette RCN, Tunstall BJ, Mani BK, Moose JE, Lee MR, Gardner E, Akhlaghi F, Roberto M, Hougland JL, Zigman JM, Koob GF, Vendruscolo LF, Leggio L. A closer look at alcohol-induced changes in the ghrelin system: novel insights from preclinical and clinical data. Addict Biol 2022; 27:e13033. [PMID: 33908131 PMCID: PMC8548413 DOI: 10.1111/adb.13033] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 01/16/2021] [Accepted: 03/06/2021] [Indexed: 02/06/2023]
Abstract
Ghrelin is a gastric-derived peptide hormone with demonstrated impact on alcohol intake and craving, but the reverse side of this bidirectional link, that is, the effects of alcohol on the ghrelin system, remains to be fully established. To further characterize this relationship, we examined (1) ghrelin levels via secondary analysis of human laboratory alcohol administration experiments with heavy-drinking participants; (2) expression of ghrelin, ghrelin receptor, and ghrelin-O-acyltransferase (GOAT) genes (GHRL, GHSR, and MBOAT4, respectively) in post-mortem brain tissue from individuals with alcohol use disorder (AUD) versus controls; (3) ghrelin levels in Ghsr knockout and wild-type rats following intraperitoneal (i.p.) alcohol administration; (4) effect of alcohol on ghrelin secretion from gastric mucosa cells ex vivo and GOAT enzymatic activity in vitro; and (5) ghrelin levels in rats following i.p. alcohol administration versus a calorically equivalent non-alcoholic sucrose solution. Acyl- and total-ghrelin levels decreased following acute alcohol administration in humans, but AUD was not associated with changes in central expression of ghrelin system genes in post-mortem tissue. In rats, alcohol decreased acyl-ghrelin, but not des-acyl-ghrelin, in both Ghsr knockout and wild-type rats. No dose-dependent effects of alcohol were observed on acyl-ghrelin secretion from gastric mucosa cells or on GOAT acylation activity. Lastly, alcohol and sucrose produced distinct effects on ghrelin in rats despite equivalent caloric value. Our findings suggest that alcohol acutely decreases peripheral ghrelin concentrations in vivo, but not in proportion to alcohol's caloric value or through direct interaction with ghrelin-secreting gastric mucosal cells, the ghrelin receptor, or the GOAT enzyme.
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Affiliation(s)
- Sara L. Deschaine
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse and National, Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Baltimore, Maryland, USA
| | - Mehdi Farokhnia
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse and National, Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Baltimore, Maryland, USA,Center on Compulsive Behaviors, National Institutes of Health, Bethesda, Maryland, USA,Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA
| | - Adriana Gregory-Flores
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse and National, Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Baltimore, Maryland, USA,Neurobiology of Addiction Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland, USA
| | - Lia J. Zallar
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse and National, Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Baltimore, Maryland, USA,Neurobiology of Addiction Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland, USA
| | - Zhi-Bing You
- Neuropsychopharmacology Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland, USA
| | - Hui Sun
- Clinical Core Laboratory, Office of the Clinical Director, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland, USA
| | - Deon M. Harvey
- Office of the Scientific Director, National Institute on Drug Abuse, Baltimore, Maryland, USA
| | - Renata C. N. Marchette
- Center on Compulsive Behaviors, National Institutes of Health, Bethesda, Maryland, USA,Neurobiology of Addiction Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland, USA
| | - Brendan J. Tunstall
- Neurobiology of Addiction Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland, USA
| | - Bharath K. Mani
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Jacob E. Moose
- Syracuse Biomaterials Institute, Syracuse University, Syracuse, New York, USA,Department of Chemistry, Syracuse University, Syracuse, New York, USA
| | - Mary R. Lee
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse and National, Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Baltimore, Maryland, USA
| | - Eliot Gardner
- Neuropsychopharmacology Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland, USA
| | - Fatemeh Akhlaghi
- Clinical Pharmacokinetics Research Laboratory, Department of Biomedical and Pharmaceutical Sciences, University of Rhode Island, Kingston, Rhode Island, USA
| | - Marisa Roberto
- Department of Neuroscience, The Scripps Research Institute, La Jolla, California, USA
| | - James L. Hougland
- Syracuse Biomaterials Institute, Syracuse University, Syracuse, New York, USA,Department of Chemistry, Syracuse University, Syracuse, New York, USA,BioInspired Syracuse, Syracuse University, Syracuse, New York, USA
| | - Jeffrey M. Zigman
- Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA,Division of Endocrinology, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA,Department of Psychiatry, UT Southwestern Medical Center, Dallas, Texas, USA
| | - George F. Koob
- Neurobiology of Addiction Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland, USA
| | - Leandro F. Vendruscolo
- Neurobiology of Addiction Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland, USA
| | - Lorenzo Leggio
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse and National, Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Baltimore, Maryland, USA,Center on Compulsive Behaviors, National Institutes of Health, Bethesda, Maryland, USA,Medication Development Program, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, Maryland, USA,Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, School of Public Health, Brown University, Providence, Rhode Island, USA,Division of Addiction Medicine, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA,Department of Neuroscience, Georgetown University Medical Center, Washington, District of Columbia, USA
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Deschaine SL, Leggio L. From "Hunger Hormone" to "It's Complicated": Ghrelin Beyond Feeding Control. Physiology (Bethesda) 2022; 37:5-15. [PMID: 34964687 PMCID: PMC8742734 DOI: 10.1152/physiol.00024.2021] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Discovered as a peptide involved in releasing growth hormone, ghrelin was initially characterized as the "hunger hormone." However, emerging research indicates that ghrelin appears to play an important part in relaying information regarding nutrient availability and value and adjusting physiological and motivational processes accordingly. These functions make ghrelin an interesting therapeutic candidate for metabolic and neuropsychiatric diseases involving disrupted nutrition that can further potentiate the rewarding effect of maladaptive behaviors.
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Affiliation(s)
- Sara L. Deschaine
- 1Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse and National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Baltimore and Bethesda, Maryland
| | - Lorenzo Leggio
- 1Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse and National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Baltimore and Bethesda, Maryland,2Medication Development Program, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, Maryland,3Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, School of Public Health, Brown University, Providence, Rhode Island,4Division of Addiction Medicine, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, Maryland,5Department of Neuroscience, Georgetown University Medical Center, Washington, District of Columbia
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Shevchouk OT, Tufvesson-Alm M, Jerlhag E. An Overview of Appetite-Regulatory Peptides in Addiction Processes; From Bench to Bed Side. Front Neurosci 2021; 15:774050. [PMID: 34955726 PMCID: PMC8695496 DOI: 10.3389/fnins.2021.774050] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 11/08/2021] [Indexed: 12/17/2022] Open
Abstract
There is a substantial need for new pharmacological treatments of addiction, and appetite-regulatory peptides are implied as possible candidates. Appetite regulation is complex and involves anorexigenic hormones such as glucagon-like peptide-1 (GLP-1) and amylin, and orexigenic peptides like ghrelin and all are well-known for their effects on feeding behaviors. This overview will summarize more recent physiological aspects of these peptides, demonstrating that they modulate various aspects of addiction processes. Findings from preclinical, genetic, and experimental clinical studies exploring the association between appetite-regulatory peptides and the acute or chronic effects of addictive drugs will be introduced. Short or long-acting GLP-1 receptor agonists independently attenuate the acute rewarding properties of addictive drugs or reduce the chronic aspects of drugs. Genetic variation of the GLP-1 system is associated with alcohol use disorder. Also, the amylin pathway modulates the acute and chronic behavioral responses to addictive drugs. Ghrelin has been shown to activate reward-related behaviors. Moreover, ghrelin enhances, whereas pharmacological or genetic suppression of the ghrelin receptor attenuates the responses to various addictive drugs. Genetic studies and experimental clinical studies further support the associations between ghrelin and addiction processes. Further studies should explore the mechanisms modulating the ability of appetite-regulatory peptides to reduce addiction, and the effects of combination therapies or different diets on substance use are warranted. In summary, these studies provide evidence that appetite-regulatory peptides modulate reward and addiction processes, and deserve to be investigated as potential treatment target for addiction.
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Affiliation(s)
- Olesya T Shevchouk
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Maximilian Tufvesson-Alm
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Elisabet Jerlhag
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
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Colvin KJ, Killen HS, Kanter MJ, Halperin MC, Engel L, Dickinson MB, Fimmel AI, Holland JG, Currie PJ. Differential effects of intra-ventral tegmental area ghrelin and glucagon-like peptide-1 on the stimulatory action of D-amphetamine and cocaine-induced ethanol intake in male Sprague Dawley rats. Behav Brain Res 2021; 421:113726. [PMID: 34954300 DOI: 10.1016/j.bbr.2021.113726] [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: 09/08/2021] [Revised: 12/15/2021] [Accepted: 12/17/2021] [Indexed: 12/24/2022]
Abstract
In order to further elucidate the role of mesolimbic peptides in the expression of ethanol reward, the present study investigated the effects of ghrelin and glucagon-like peptide-1 (GLP-1) on ethanol intake, in addition to ethanol intake stimulated by systemic d-amphetamine or cocaine treatment. While a number of studies suggest that ghrelin plays an important role in mesolimbic reward, emerging data now indicate that GLP-1 receptor mechanisms inhibit reward signaling, possibly by directly or indirectly inhibiting ghrelinergic activity within the mesolimbic system. In the present study all rats were initially habituated to a 6% ethanol solution. We then demonstrated that intraperitoneal injections of d-amphetamine and cocaine increased ethanol intake compared to the vehicle condition. In subsequent testing we examined the effects of ventral tegmental area (VTA) ghrelin or vehicle paired with a fixed dose of d-amphetamine or vehicle. In separate rats we then investigated the impact of the GLP-1 agonist exendin-4 (Ex-4), injected into the VTA, on ethanol intake alone, or when Ex-4 was co-administered with d-amphetamine or cocaine. Our results indicated that VTA ghrelin significantly increased ethanol intake, and most importantly, potentiated the effect of d-amphetamine and cocaine on ethanol consumption. Conversely, VTA Ex-4 inhibited ethanol intake and antagonized the stimulatory effect of d-amphetamine and cocaine on ethanol consumption. In a final study we further demonstrated that VTA Ex-4 treatment significantly inhibited the combined stimulatory effects of ghrelin paired with d-amphetamine or ghrelin paired with cocaine. Overall our findings are consistent with a critical role for both ghrelin and GLP-1 receptor mechanisms in mesolimbic ethanol reward circuitry. Moreover, our results further suggest that ghrelin and GLP-1 modulate the stimulatory effect of psychostimulants on ethanol intake.
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Affiliation(s)
- Kayla J Colvin
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, USA
| | - Henry S Killen
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, USA
| | - Maxwell J Kanter
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, USA
| | - Maximilian C Halperin
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, USA
| | - Liv Engel
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, USA
| | - Matthew B Dickinson
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, USA
| | - Anna I Fimmel
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, USA
| | - James G Holland
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, USA
| | - Paul J Currie
- Department of Psychology, Reed College, 3203 SE Woodstock Blvd., Portland, OR 97202, USA.
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Micioni Di Bonaventura E, Botticelli L, Del Bello F, Giorgioni G, Piergentili A, Quaglia W, Cifani C, Micioni Di Bonaventura MV. Assessing the role of ghrelin and the enzyme ghrelin O-acyltransferase (GOAT) system in food reward, food motivation, and binge eating behavior. Pharmacol Res 2021; 172:105847. [PMID: 34438062 DOI: 10.1016/j.phrs.2021.105847] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/19/2021] [Accepted: 08/20/2021] [Indexed: 02/06/2023]
Abstract
The peripheral peptide hormone ghrelin is a powerful stimulator of food intake, which leads to body weight gain and adiposity in both rodents and humans. The hormone, thus, increases the vulnerability to obesity and binge eating behavior. Several studies have revealed that ghrelin's functions are due to its interaction with the growth hormone secretagogue receptor type 1a (GHSR1a) in the hypothalamic area; besides, ghrelin also promotes the reinforcing properties of hedonic food, acting at extra-hypothalamic sites and interacting with dopaminergic, cannabinoid, opioid, and orexin signaling. The hormone is primarily present in two forms in the plasma and the enzyme ghrelin O-acyltransferase (GOAT) allows the acylation reaction which causes the transformation of des-acyl-ghrelin (DAG) to the active form acyl-ghrelin (AG). DAG has been demonstrated to show antagonist properties; it is metabolically active, and counteracts the effects of AG on glucose metabolism and lipolysis, and reduces food consumption, body weight, and hedonic feeding response. Both peptides seem to influence the hypothalamic-pituitary-adrenal (HPA) axis and the corticosterone/cortisol level that drive the urge to eat under stressful conditions. These findings suggest that DAG and inhibition of GOAT may be targets for obesity and bingeing-related eating disorders and that AG/DAG ratio may be an important potential biomarker to assess the risk of developing maladaptive eating behaviors.
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Affiliation(s)
| | - Luca Botticelli
- School of Pharmacy, Pharmacology Unit, University of Camerino, via Madonna delle Carceri, 9, 62032 Camerino, Italy
| | - Fabio Del Bello
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, via S. Agostino, 1, 62032 Camerino, Italy
| | - Gianfabio Giorgioni
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, via S. Agostino, 1, 62032 Camerino, Italy
| | - Alessandro Piergentili
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, via S. Agostino, 1, 62032 Camerino, Italy
| | - Wilma Quaglia
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, via S. Agostino, 1, 62032 Camerino, Italy
| | - Carlo Cifani
- School of Pharmacy, Pharmacology Unit, University of Camerino, via Madonna delle Carceri, 9, 62032 Camerino, Italy.
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Orellana ER, Piscura MK, Horvath N, Hajnal A. Differential Response in Ethanol Behaviors of Female Rats Given Various Weight Loss Surgeries. Alcohol Alcohol 2021; 56:599-604. [PMID: 34343232 DOI: 10.1093/alcalc/agab054] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 07/12/2021] [Accepted: 07/14/2021] [Indexed: 12/15/2022] Open
Abstract
AIMS Currently, the only effective treatment for morbid obesity and its comorbidities is weight loss surgery (WLS). Growing evidence suggests that different types of WLS, such as Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG), have differential effects on alcohol consumption in humans and rats. Thus, we aimed to directly compare the effects of these two surgical procedures, for the first time in female rats, and to determine whether presence or absence of the ghrelin-producing stomach tissue has critical influence on postoperative alcohol intake. METHODS We performed two experiments using an identical behavioral protocol, a continuous-access two-bottle choice protocol for various concentrations of ethanol (EtOH). In Experiment 1, 23 high fat diet (HFD) obese, female rats were randomized to three groups: RYGB, SG or sham-operated food-restricted (Sham) controls. In Experiment 2, HFD obese female rats received either sham (n = 11) or a modified RYGB surgery where the remnant stomach was removed (RYGB-X; n = 12). RESULTS SG rats drank significantly less than RYGB for 4, 6 and 8% and significantly less than Sham for 6, 8 and 8% reinstatement. RYGB-X consumed significantly less EtOH than Sham across all concentrations, reaching significance for 6 and 8% reinstatement. CONCLUSION These findings confirm reduced EtOH consumption by female SG rats as opposed to increased intake following RYGB, and provide the first experimental evidence that the remnant stomach in the RYGB procedure is contributory. Future studies in rats and humans are warranted to confirm that ghrelin plays a critical role in susceptibility to AUD development following WLS.
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Affiliation(s)
- Elise R Orellana
- Georgetown University, School of Medicine, Department of Biochemistry and Molecular & Cellular Biology, 3900 Reservoir Road NW, Washington, DC, 20009
| | - Mary K Piscura
- The Pennsylvania State University, College of Medicine, Department of Neural and Behavioral Sciences, 700 HMC Crescent road, Hershey, PA 17033
| | - Nelli Horvath
- The Pennsylvania State University, College of Medicine, Department of Neural and Behavioral Sciences, 700 HMC Crescent road, Hershey, PA 17033
| | - Andras Hajnal
- The Pennsylvania State University, College of Medicine, Department of Neural and Behavioral Sciences, 700 HMC Crescent road, Hershey, PA 17033
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al'Absi M, DeAngelis B, Nakajima M, Hatsukami D, Allen S. Early life adversity and appetite hormones: The effects of smoking status, nicotine withdrawal, and relapse on ghrelin and peptide YY during smoking cessation. Addict Behav 2021; 118:106866. [PMID: 33640833 DOI: 10.1016/j.addbeh.2021.106866] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 12/28/2020] [Accepted: 02/01/2021] [Indexed: 12/30/2022]
Abstract
There is evidence suggesting that ghrelin and peptide YY (PYY) modulate stress responses and the rewarding effects of drugs, although no research has examined the impact of exposure to early life stress on these hormones in smokers nor during smoking cessation. This study examined the relationships between early life adversity (ELA) and circulating ghrelin and PYY during ad libitum smoking and early withdrawal in tobacco smokers (N = 98) who were interested in cessation. We also included a comparison group of nonsmokers (N = 36). We prospectively compared levels of hormones between smokers who were successful in quitting within a 2-week period, smokers who relapsed during that period, and nonsmokers. Results showed that ELA was positively associated with elevated ghrelin in nonsmokers. Among those reporting no ELA, successful quitters had higher ghrelin levels than nonsmokers during ad libitum smoking, while relapsers had higher ghrelin levels than nonsmokers during withdrawal. In addition, having no ELA was associated with a decline in ghrelin from the ad libitum to abstinence sessions in successful quitters; this withdrawal-related decline was not found in relapsers. Although effects of ELA, smoking group, and time on PYY were not significant, greater PYY was associated with reduced urges to smoke during withdrawal. These findings suggest the importance of considering changes in appetite-related hormones in individuals who are dependent on tobacco. This research provides additional indications for effects of ELA on appetite-stimulating hormones.
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Edvardsson CE, Vestlund J, Jerlhag E. A ghrelin receptor antagonist reduces the ability of ghrelin, alcohol or amphetamine to induce a dopamine release in the ventral tegmental area and in nucleus accumbens shell in rats. Eur J Pharmacol 2021; 899:174039. [PMID: 33737011 DOI: 10.1016/j.ejphar.2021.174039] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/10/2021] [Accepted: 03/11/2021] [Indexed: 11/24/2022]
Abstract
The orexigenic peptide ghrelin increases the release of dopamine in the nucleus accumbens (NAc) shell via central ghrelin receptors, especially those located in the ventral tegmental area (VTA). The activity of the VTA dopamine neurons projecting to NAc shell, involves somatodendritic dopamine release within the VTA. However, the effects of ghrelin on the concomitant dopamine release in the VTA and NAc shell is unknown. It is further unknown whether addictive drugs, such as alcohol and amphetamine, enhance the dopamine levels in both these areas via ghrelin receptor dependent mechanisms. Thus, the effects of a ghrelin receptor antagonist, JMV2959, on the ability of i) central ghrelin ii) systemic alcohol or iii) systemic amphetamine to increase the dopamine release in the VTA and in the NAc shell in rats by using in vivo microdialysis was explored. We showed that systemic administration of JMV2959 blocks the ability of central ghrelin to increases dopamine release in the VTA and the NAc shell, and reduces the alcohol- and amphetamine-induced dopamine release in both these areas. Locomotor activity studies was then conducted in an attempt to correlate the ghrelin-induced dopamine release in the VTA to a behavioural outcome. These revealed that local infusion of a dopamine D1 receptor antagonist into the VTA blocks the ability of central ghrelin to cause a locomotor stimulation in mice. Collectively, this study adds to the growing body of evidence indicating that ghrelin signalling modulates the ability of ghrelin, and addictive drugs, to activate the mesoaccumbal dopamine pathway.
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Affiliation(s)
- Christian E Edvardsson
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Jesper Vestlund
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Elisabet Jerlhag
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
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Shi X, Guan K, Peng X, Xu B, Zhou X, Wang S, Xu S, Zheng M, Huang J, Wan X, Guan W, Su KP, Ye M, Gao X, Yin Z, Li X. Ghrelin modulates dopaminergic neuron formation and attention deficit hyperactivity disorder-like behaviors: From animals to human models. Brain Behav Immun 2021; 94:327-337. [PMID: 33412253 DOI: 10.1016/j.bbi.2020.12.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 12/22/2020] [Accepted: 12/28/2020] [Indexed: 10/22/2022] Open
Abstract
Attention deficit hyperactivity disorder (ADHD) is one of the most prevalent psychiatric disorders in children. The orexigenic hormone ghrelin is important in neuroprotection and neurodevelopment, which may play an important role in psychopathogenesis of ADHD. This study aimed to systematically investigate the genomic and pharmacological manipulations of ghrelin functioning in ADHD-like symptoms in zebrafish models and validated the effects of ghrelin polymorphisms in human subjects with ADHD. We firstly generated ghrelinΔ/Δ zebrafish mutant, which displayed hyperactive, attention deficit-like and impulsive-like behaviors, as well as endophenotypes, mimicking human ADHD. GhrelinΔ/Δ zebrafish exhibited downregulated expression levels of wnt1, wnt3a, wnt5a that are critical for dopaminergic neuron development to possibly regulate their number and spatial organization. Pharmacological blockade of wnt signaling with XAV939 induced a reduced moving activity and less dopaminergic neurons; whereas, wnt agonist SB415286 rescued hyperactivity and dopaminergic neuron loss in ghrelinΔ/Δ zebrafish. In addition, we further identified and validated a SNP, rs696217, on orexigenic hormone preproghrelin/ghrelin (T408T, Met72Met) to be associated with a higher risk of ADHD in a case-controlled association study with 248 subjects with ADHD and 208 subjects of healthy controls. Together, our results reveal a novel endogenous role for orexigenic hormone ghrelin in ADHD, which provides insights into genetic regulation and drug screens for the identification of novel treatments of ADHD.
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Affiliation(s)
- Xulai Shi
- The Affiliated Kangning Hospital of Wenzhou Medical University, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, PR China
| | - Kaiyu Guan
- The Affiliated Kangning Hospital of Wenzhou Medical University, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, PR China
| | - Xuyan Peng
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, PR China
| | - Bingru Xu
- School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, PR China
| | - Xianyong Zhou
- The Affiliated Kangning Hospital of Wenzhou Medical University, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, PR China
| | - Shao Wang
- The Affiliated Kangning Hospital of Wenzhou Medical University, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, PR China
| | - Shengnan Xu
- The Affiliated Kangning Hospital of Wenzhou Medical University, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, PR China
| | - Miaomiao Zheng
- The Affiliated Kangning Hospital of Wenzhou Medical University, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, PR China
| | - Jing Huang
- Department of Biostatistics, Epidemiology and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
| | - Xiaoyang Wan
- Institute of Infectious Liver Disease, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China
| | - Wanchun Guan
- School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, PR China
| | - Kuan-Pin Su
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK; An-Nan Hospital, China Medical University, Tainan, Taiwan
| | - Minjie Ye
- The Affiliated Kangning Hospital of Wenzhou Medical University, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, PR China
| | - Xiang Gao
- Central Laboratory, Scientific Research Department, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
| | - Zhan Yin
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, PR China.
| | - Xi Li
- The Affiliated Kangning Hospital of Wenzhou Medical University, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, PR China.
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Contribution of growth hormone secretagogue receptor (GHSR) signaling in the ventral tegmental area (VTA) to the regulation of social motivation in male mice. Transl Psychiatry 2021; 11:230. [PMID: 33879778 PMCID: PMC8058340 DOI: 10.1038/s41398-021-01350-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 03/19/2021] [Accepted: 03/30/2021] [Indexed: 01/22/2023] Open
Abstract
Most psychiatric disorders are characterized by deficits in the ability to interact socially with others. Ghrelin, a hormone normally associated with the regulation of glucose utilization and appetite, is also implicated in the modulation of motivated behaviors including those associated with food and sex rewards. Here we hypothesized that deficits in ghrelin receptor (growth hormone secretagogue receptor; GHSR) signaling are also associated with deficits in social motivation in male mice. To test this hypothesis, we compared social motivation in male mice lacking GHSR or mice treated with the GHSR antagonist JMV2959 with that of WT or vehicle-treated mice. GHSR signaling in dopamine cells of the ventral tegmental area (VTA) has been implicated in the control of sexual behavior, thus we further hypothesized that GHSR signaling in the VTA is important for social motivation. Thus, we conducted studies where we delivered JMV2959 to block GHSR in the VTA of mice, and studies where we rescued the expression of GHSR in the VTA of GHSR knockout (KO) mice. Mice lacking GHSR or injected with JMV2959 peripherally for 3 consecutive days displayed lower social motivation as reflected by a longer latency to approach a novel conspecific and shorter interaction time compared to WT or vehicle-treated controls. Furthermore, intra-VTA infusion of JMV2959 resulted in longer latencies to approach a novel conspecific, whereas GHSR KO mice with partial rescue of the GHSR showed decreased latencies to begin a novel social interaction. Together, these data suggest that GHSR in the VTA facilitate social approach in male mice, and GHSR-signaling deficits within the VTA result in reduced motivation to interact socially.
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Rejeski JJ, Fanning J, Nicklas BJ, Rejeski WJ. Six-month changes in ghrelin and glucagon-like peptide-1 with weight loss are unrelated to long-term weight regain in obese older adults. Int J Obes (Lond) 2021; 45:888-894. [PMID: 33526855 PMCID: PMC8005376 DOI: 10.1038/s41366-021-00754-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 11/19/2020] [Accepted: 01/12/2021] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND OBJECTIVE Weight loss (WL) and subsequent regain are complex physiologic processes, and our understanding of the hormonal changes associated with these processes continues to evolve. We aimed to examine the effects of behavioral WL on 6-month changes in ghrelin and GLP-1 and evaluate the effects of these changes in gut hormones on weight regain among older adults. SUBJECTS AND METHODS One hundred seventy-seven obese (BMI: 33.5 (3.5) kg/m2) older adults (66.9 ± 4.7 years, 71.2% female, 67.6% white) were randomized to WL (WL; n = 68), WL plus aerobic training (n = 79), or WL plus resistance training (n = 75) for 18 months. Ghrelin, GLP-1, power of food scale (PFS), and weight were measured at baseline, 6 months, and 18 months. RESULTS There was no differential treatment effect on change in either gut hormone, however, there was a significant time effect across all groups (p < 0.001), with increases in ghrelin (∆ = +106.77 pg/ml; 95% CI = + 84.82, +128.71) and decreases in GLP-1 (∆ = -4.90 pM; 95% CI = -6.27, -3.51) at 6-month. Ratings on the PFS decreased from baseline to 6-month and there was significant loss of weight from baseline to either 6- or 18-month, ∆ = -7.96 kg; 95% CI = -7.95, -8.78 and ∆ = -7.80 kg; 95% CI = -8.93, -6.65, respectively (p < 0.001). Changes in ghrelin and GLP-1 at 6-month did not predict weight regain from 6- to 18-month. DISCUSSION AND CONCLUSION Among older adults with obesity and cardiometabolic disease, the intensive phase of dietary WL results in increasing levels of ghrelin and decreasing levels of GLP-1 that are unrelated to weight regain a year later. Registered with ClinicalTrials.gov (NCT01547182).
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Affiliation(s)
- Jared J Rejeski
- Department of Internal Medicine, Section on Gastroenterology, Wake Forest School of Medicine, Winston-Salem, NC, USA.
| | - Jason Fanning
- Department of Health & Exercise Science, Wake Forest University, Winston-Salem, NC, USA
| | - Barbara J Nicklas
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - W Jack Rejeski
- Department of Health & Exercise Science, Wake Forest University, Winston-Salem, NC, USA
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
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Morley KC, Perry CJ, Watt J, Hurzeler T, Leggio L, Lawrence AJ, Haber P. New approved and emerging pharmacological approaches to alcohol use disorder: a review of clinical studies. Expert Opin Pharmacother 2021; 22:1291-1303. [PMID: 33615945 DOI: 10.1080/14656566.2021.1892641] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
introduction: The number of medications approved for AUD is small and they generally have limited efficacy. We need new pharmacotherapies for the management of AUD.Areas covered: In this review, the authors aim to synthesise literature for new approved and emerging pharmacotherapies for AUD. Recently approved medications include nalmefene, which was approved in Europe and Australia for the purposes of controlled drinking. Baclofen has also been approved in France but not in other countries. Off label medications including topiramate and gabapentin have received significant attention with multiple RCTs and meta-analyses and have widespread use in several countries including the USA. Several novel medications have emerged over the last decade but further work is required to determine their efficacy and safety for the widespread management of AUD.Expert opinion: Despite significant advances in our understanding of the neurobiological basis of factors that contribute to the development and maintenance of AUD, there have been few new AUD medications approved for almost 20 years. There are many challenges to the development and introduction of new pharmacotherapies for AUD. Strategies for improving the translational pipeline include drug repurposing and utilisation of human acute laboratory models.
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Affiliation(s)
- Kirsten C Morley
- Central Clinical School, Sydney School of Medicine, Faculty of Medicine & Health, University of Sydney, NSW, Australia.,Edith Collins Centre (Alcohol, Drugs and Toxicology), Sydney Local Health District, Royal Prince Alfred Hospital, Camperdown, NSW, Australia
| | - Christina J Perry
- University of Melbourne, Mental Health Theme, Florey Institute of Neuroscience and Mental Health, Parkville, Australia
| | - Joshua Watt
- Edith Collins Centre (Alcohol, Drugs and Toxicology), Sydney Local Health District, Royal Prince Alfred Hospital, Camperdown, NSW, Australia
| | - Tristan Hurzeler
- Central Clinical School, Sydney School of Medicine, Faculty of Medicine & Health, University of Sydney, NSW, Australia
| | - Lorenzo Leggio
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, National Institute on Drug Abuse and National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Baltimore and Bethesda, USA.,Department of Neuroscience, Georgetown University Medical Center, Washington, USA.,Medication Development Program, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, USA
| | - Andrew J Lawrence
- University of Melbourne, Mental Health Theme, Florey Institute of Neuroscience and Mental Health, Parkville, Australia.,Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, School of Public Health, Brown University, Providence, USA
| | - Paul Haber
- Central Clinical School, Sydney School of Medicine, Faculty of Medicine & Health, University of Sydney, NSW, Australia.,Edith Collins Centre (Alcohol, Drugs and Toxicology), Sydney Local Health District, Royal Prince Alfred Hospital, Camperdown, NSW, Australia.,Division of Addiction Medicine, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, USA
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Cannabinoid-Induced Conditioned Place Preference, Intravenous Self-Administration, and Behavioral Stimulation Influenced by Ghrelin Receptor Antagonism in Rats. Int J Mol Sci 2021; 22:ijms22052397. [PMID: 33673659 PMCID: PMC7957642 DOI: 10.3390/ijms22052397] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 02/13/2021] [Accepted: 02/21/2021] [Indexed: 11/24/2022] Open
Abstract
Cannabis/cannabinoids are widely used for recreational and therapy purposes, but their risks are largely disregarded. However, cannabinoid-associated use disorders and dependence are alarmingly increasing and an effective treatment is lacking. Recently, the growth hormone secretagogue receptor (GHSR1A) antagonism was proposed as a promising mechanism for drug addiction therapy. However, the role of GHS-R1A and its endogenous ligand ghrelin in cannabinoid abuse remains unclear. Therefore, the aim of our study was to investigate whether the GHS-R1A antagonist JMV2959 could reduce the tetrahydrocannabinol (THC)-induced conditioned place preference (CPP) and behavioral stimulation, the WIN55,212-2 intravenous self-administration (IVSA), and the tendency to relapse. Following an ongoing WIN55,212-2 self-administration, JMV2959 3 mg/kg was administered intraperitoneally 20 min before three consequent daily 120-min IVSA sessions under a fixed ratio FR1, which significantly reduced the number of the active lever-pressing, the number of infusions, and the cannabinoid intake. Pretreatment with JMV2959 suggested reduction of the WIN55,212-2-seeking/relapse-like behavior tested in rats on the twelfth day of the forced abstinence period. On the contrary, pretreatment with ghrelin significantly increased the cannabinoid IVSA as well as enhanced the relapse-like behavior. Co-administration of ghrelin with JMV2959 abolished/reduced the significant efficacy of the GHS-R1A antagonist in the cannabinoid IVSA. Pretreatment with JMV2959 significantly and dose-dependently reduced the manifestation of THC-induced CPP. The THC-CPP development was reduced after the simultaneous administration of JMV2959 with THC during conditioning. JMV2959 also significantly reduced the THC-induced behavioral stimulation in the LABORAS cage. Our findings suggest that GHS-R1A importantly participates in the rewarding/reinforcing effects of cannabinoids.
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Charalambous C, Lapka M, Havlickova T, Syslova K, Sustkova-Fiserova M. Alterations in Rat Accumbens Dopamine, Endocannabinoids and GABA Content During WIN55,212-2 Treatment: The Role of Ghrelin. Int J Mol Sci 2020; 22:ijms22010210. [PMID: 33379212 PMCID: PMC7795825 DOI: 10.3390/ijms22010210] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 12/21/2020] [Accepted: 12/24/2020] [Indexed: 01/22/2023] Open
Abstract
The endocannabinoid/CB1R system as well as the central ghrelin signalling with its growth hormone secretagogoue receptors (GHS-R1A) are importantly involved in food intake and reward/reinforcement processing and show distinct overlaps in distribution within the relevant brain regions including the hypothalamus (food intake), the ventral tegmental area (VTA) and the nucleus accumbens (NAC) (reward/reinforcement). The significant mutual interaction between these systems in food intake has been documented; however, the possible role of ghrelin/GHS-R1A in the cannabinoid reinforcement effects and addiction remain unclear. Therefore, the principal aim of the present study was to investigate whether pretreatment with GHS-R1A antagonist/JMV2959 could reduce the CB1R agonist/WIN55,212-2–induced dopamine efflux in the nucleus accumbens shell (NACSh), which is considered a crucial trigger impulse of the addiction process. The synthetic aminoalklylindol cannabinoid WIN55,212-2 administration into the posterior VTA induced significant accumbens dopamine release, which was significantly reduced by the 3 mg/kg i.p. JMV2959 pretreatment. Simultaneously, the cannabinoid-increased accumbens dopamine metabolic turnover was significantly augmented by the JMV2959 pretreament. The intracerebral WIN55,212-2 administration also increased the endocannabinoid arachidonoylethanolamide/anandamide and the 2-arachidonoylglycerol/2-AG extracellular levels in the NACSh, which was moderately but significantly attenuated by the JMV2959 pretreatment. Moreover, the cannabinoid-induced decrease in accumbens γ-aminobutyric acid/gamma-aminobutyric acid levels was reversed by the JMV2959 pretreatment. The behavioural study in the LABORAS cage showed that 3 mg/kg JMV2959 pretreatment also significantly reduced the systemic WIN55,212-2-induced behavioural stimulation. Our results demonstrate that the ghrelin/GHS-R1A system significantly participates in the rewarding/reinforcing effects of the cannabinoid/CB1 agonist that are involved in cannabinoid addiction processing.
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Affiliation(s)
- Chrysostomos Charalambous
- Department of Addictology, First Faculty of Medicine, Charles University, Apolinarska 4, 128 00 Prague 2, Czech Republic;
| | - Marek Lapka
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 100 34 Prague 10, Czech Republic; (M.L.); (T.H.)
| | - Tereza Havlickova
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 100 34 Prague 10, Czech Republic; (M.L.); (T.H.)
| | - Kamila Syslova
- Laboratory of Medicinal Diagnostics, Department of Organic Technology, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague 6, Czech Republic;
| | - Magdalena Sustkova-Fiserova
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 100 34 Prague 10, Czech Republic; (M.L.); (T.H.)
- Correspondence: ; Tel.: +420-267-102-450; Fax: +420-267-102-461
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Cornejo MP, Mustafá ER, Barrile F, Cassano D, De Francesco PN, Raingo J, Perello M. THE INTRIGUING LIGAND-DEPENDENT AND LIGAND-INDEPENDENT ACTIONS OF THE GROWTH HORMONE SECRETAGOGUE RECEPTOR ON REWARD-RELATED BEHAVIORS. Neurosci Biobehav Rev 2020; 120:401-416. [PMID: 33157147 DOI: 10.1016/j.neubiorev.2020.10.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/18/2020] [Accepted: 10/20/2020] [Indexed: 02/07/2023]
Abstract
The growth hormone secretagogue receptor (GHSR) is a G-protein-coupled receptor (GPCR) highly expressed in the brain, and also in some peripheral tissues. GHSR activity is evoked by the stomach-derived peptide hormone ghrelin and abrogated by the intestine-derived liver-expressed antimicrobial peptide 2 (LEAP2). In vitro, GHSR displays ligand-independent actions, including a high constitutive activity and an allosteric modulation of other GPCRs. Beyond its neuroendocrine and metabolic effects, cumulative evidence shows that GHSR regulates the activity of the mesocorticolimbic pathway and modulates complex reward-related behaviors towards different stimuli. Here, we review current evidence indicating that ligand-dependent and ligand-independent actions of GHSR enhance reward-related behaviors towards appetitive stimuli and drugs of abuse. We discuss putative neuronal networks and molecular mechanisms that GHSR would engage to modulate such reward-related behaviors. Finally, we briefly discuss imaging studies showing that ghrelin would also regulate reward processing in humans. Overall, we conclude that GHSR is a key regulator of the mesocorticolimbic pathway that influences its activity and, consequently, modulates reward-related behaviors via ligand-dependent and ligand-independent actions.
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Affiliation(s)
- María P Cornejo
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA). National University of La Plata], 1900 La Plata, Buenos Aires, Argentina
| | - Emilio R Mustafá
- Laboratory of Electrophysiology of the IMBICE, 1900 La Plata, Buenos Aires, Argentina
| | - Franco Barrile
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA). National University of La Plata], 1900 La Plata, Buenos Aires, Argentina
| | - Daniela Cassano
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA). National University of La Plata], 1900 La Plata, Buenos Aires, Argentina
| | - Pablo N De Francesco
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA). National University of La Plata], 1900 La Plata, Buenos Aires, Argentina
| | - Jesica Raingo
- Laboratory of Electrophysiology of the IMBICE, 1900 La Plata, Buenos Aires, Argentina
| | - Mario Perello
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA). National University of La Plata], 1900 La Plata, Buenos Aires, Argentina.
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Cornejo MP, Barrile F, Cassano D, Aguggia JP, García Romero G, Reynaldo M, Andreoli MF, De Francesco PN, Perello M. Growth hormone secretagogue receptor in dopamine neurons controls appetitive and consummatory behaviors towards high-fat diet in ad-libitum fed mice. Psychoneuroendocrinology 2020; 119:104718. [PMID: 32535402 DOI: 10.1016/j.psyneuen.2020.104718] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/11/2020] [Accepted: 05/12/2020] [Indexed: 01/10/2023]
Abstract
Growth hormone secretagogue receptor (GHSR), the receptor for ghrelin, is expressed in key brain nuclei that regulate food intake. The dopamine (DA) pathways have long been recognized to play key roles mediating GHSR effects on feeding behaviors. Here, we aimed to determine the role of GHSR in DA neurons controlling appetitive and consummatory behaviors towards high fat (HF) diet. For this purpose, we crossed reactivable GHSR-deficient mice with DA transporter (DAT)-Cre mice, which express Cre recombinase under the DAT promoter that is active exclusively in DA neurons, to generate mice with GHSR expression limited to DA neurons (DAT-GHSR mice). We found that DAT-GHSR mice show an increase of c-Fos levels in brain areas containing DA neurons after ghrelin treatment, in a similar fashion as seen in wild-type mice; however, they did not increase food intake or locomotor activity in response to systemically- or centrally-administered ghrelin. In addition, we found that satiated DAT-GHSR mice displayed both anticipatory activity to scheduled HF diet exposure and HF intake in a binge-like eating protocol similar to those in wild-type mice, whereas GHSR-deficient mice displayed impaired responses. We conclude that GHSR expression in DA neurons is sufficient to both mediate increased anticipatory activity to a scheduled HF diet exposure and fully orchestrate binge-like HF intake, but it is insufficient to restore the acute orexigenic or locomotor effects of ghrelin treatment. Thus, GHSR in DA neurons affects appetitive and consummatory behaviors towards HF diet that take place in the absence of caloric needs.
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Affiliation(s)
- María Paula Cornejo
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], 1900 La Plata, Buenos Aires, Argentina
| | - Franco Barrile
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], 1900 La Plata, Buenos Aires, Argentina
| | - Daniela Cassano
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], 1900 La Plata, Buenos Aires, Argentina
| | - Julieta Paola Aguggia
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], 1900 La Plata, Buenos Aires, Argentina
| | - Guadalupe García Romero
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], 1900 La Plata, Buenos Aires, Argentina
| | - Mirta Reynaldo
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], 1900 La Plata, Buenos Aires, Argentina
| | - María Florencia Andreoli
- Laboratory of Experimental Neurodevelopment, Institute of Development and Pediatric Research (IDIP), La Plata Children's Hospital and Scientific Research Commission, Province of Buenos Aires (CIC-PBA)], La Plata, Buenos Aires, Argentina
| | - Pablo Nicolás De Francesco
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], 1900 La Plata, Buenos Aires, Argentina
| | - Mario Perello
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology [IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata], 1900 La Plata, Buenos Aires, Argentina.
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Blanco-Gandía MC, Miñarro J, Rodríguez-Arias M. Common Neural Mechanisms of Palatable Food Intake and Drug Abuse: Knowledge Obtained with Animal Models. Curr Pharm Des 2020; 26:2372-2384. [DOI: 10.2174/1381612826666200213123608] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 01/23/2020] [Indexed: 02/07/2023]
Abstract
Eating is necessary for survival, but it is also one of the great pleasures enjoyed by human beings.
Research to date shows that palatable food can be rewarding in a similar way to drugs of abuse, indicating
considerable comorbidity between eating disorders and substance-use disorders. Analysis of the common characteristics
of both types of disorder has led to a new wave of studies proposing a Gateway Theory of food as a vulnerability
factor that modulates the development of drug addiction. The homeostatic and hedonic mechanisms of
feeding overlap with some of the mechanisms implicated in drug abuse and their interaction plays a crucial role in
the development of drug addiction. Studies in animal models have shown how palatable food sensitizes the reward
circuit and makes individuals more sensitive to other substances of abuse, such as cocaine or alcohol. However,
when palatable food is administered continuously as a model of obesity, the consequences are different, and
studies provide controversial data. In the present review, we will cover the main homeostatic and hedonic mechanisms
that regulate palatable food intake behavior and will explain, using animal models, how different types of
diet and their intake patterns have direct consequences on the rewarding effects of psychostimulants and ethanol.
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Affiliation(s)
- Maria C. Blanco-Gandía
- Department of Psychology and Sociology, University of Zaragoza, C/ Ciudad Escolar s/n, 44003, Teruel, Spain
| | - José Miñarro
- Unit of Research Psychobiology of Drug Dependence, Department of Psychobiology, Facultad de Psicologia, Universitat de Valencia, Avda. Blasco Ibanez, 21, 46010 Valencia, Spain
| | - Marta Rodríguez-Arias
- Unit of Research Psychobiology of Drug Dependence, Department of Psychobiology, Facultad de Psicologia, Universitat de Valencia, Avda. Blasco Ibanez, 21, 46010 Valencia, Spain
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Yadegary A, Nazari-Serenjeh F, Darbandi N. Synergistic improvement effect of nicotine-ghrelin co-injection into the anterior ventral tegmental area on morphine-induced amnesia. Neuropeptides 2020; 80:102025. [PMID: 32029269 DOI: 10.1016/j.npep.2020.102025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 01/15/2020] [Accepted: 01/29/2020] [Indexed: 11/15/2022]
Abstract
In the present study the effect of ghrelin or ghrelin/nicotine injection into the anterior ventral tegmental area (aVTA) on morphine-induced amnesia in passive avoidance learning have been evaluated. Also, the role of the aVTA nicotinic receptors in possible ghrelin-induced effects has been investigated. All animals were bilaterally implanted with chronic cannulas in the aVTA. A step-through type passive avoidance task was used for measurement of memory. We found that post-training subcutaneous (s.c.) injection of morphine (0.5-7.5 mg/kg) dose-dependently reduced the step-through latency, indicating morphine-induced amnesia. Post-training bilateral infusion of ghrelin (0.3, 1.5 and 3 nmol/μl) in a dose-dependent manner reversed amnesia induced by morphine (7.5 mg/kg, s.c.). Furthermore, reversal effect of ghrelin (3 nmol/μl) was blocked by pre-treatment of intra-aVTA administration of mecamylamine (1-3 μg/rat), a nicotinic acetylcholine receptor antagonist. Intra-aVTA administration of the higher dose of mecamylamine (3 μg/rat) into the aVTA by itself decreased the step-through latency and induced amnesia. In addition, post-training intra-aVTA administration of nicotine (0.25, 0.5, 1 μg/rat) which alone cannot affect memory consolidation, decreased significantly the amnesia induced by morphine (7.5 mg/kg, s.c.). Co-treatment of an ineffective dose of ghrelin (0.3 nmol/μl) with an ineffective dose of nicotine (0.25 μg/rat) significantly increased step-through latency of morphine (7.5 mg/kg, s.c.) treated animals, indicating the synergistic effect of the drugs. Taken together, our results suggest that intra-aVTA administration of ghrelin reversed morphine-induced amnesia and that ghrelin interacts synergistically with nicotine to mitigate morphine-induced amnesia.
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Affiliation(s)
- Atena Yadegary
- Department of Biology, Faculty of Science, Arak University, Arak, Iran
| | | | - Niloufar Darbandi
- Department of Biology, Faculty of Science, Arak University, Arak, Iran
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