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Kaiya H. Update on Feeding Regulation by Ghrelin in Birds: Focused on Brain Network. Zoolog Sci 2024; 41:39-49. [PMID: 38587516 DOI: 10.2108/zs230071] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 12/21/2023] [Indexed: 04/09/2024]
Abstract
Ghrelin is known to be a feeding stimulatory hormone in mammals, but in birds, in contrast to mammals, the feeding behavior is regulated in inhibitory manners. This is because the neuropeptides associated with the regulation in the brain are different from those in mammals, i.e., it has been shown that, in chickens, a corticotropin-releasing hormone family peptide, urocortin, which is a feeding-inhibitory peptide, is mainly involved in the inhibitory mechanism. However, feeding is also regulated by various neurotransmitters in the brain, and recently, their interaction with the mechanisms underlying feeding inhibition by ghrelin in birds has been intensively studied and clarified. This review summarizes these findings.
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Affiliation(s)
- Hiroyuki Kaiya
- Grandsoul Research Institute for Immunology, Inc., Utano, Uda, Nara 633-2221, Japan,
- Faculty of Science, University of Toyama, Toyama, Toyama 930-8555, Japan
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2
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Merritt CR, Garcia EJ, Brehm VD, Fox RG, Moeller FG, Anastasio NC, Cunningham KA. Ghrelin receptor antagonist JMV2959 blunts cocaine and oxycodone drug-seeking, but not self-administration, in male rats. Front Pharmacol 2023; 14:1268366. [PMID: 37795028 PMCID: PMC10545966 DOI: 10.3389/fphar.2023.1268366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 09/06/2023] [Indexed: 10/06/2023] Open
Abstract
The drug overdose crisis has spawned serious health consequences, including the increased incidence of substance use disorders (SUDs), conditions manifested by escalating medical and psychological impairments. While medication management is a key adjunct in SUD treatment, this crisis has crystallized the need to develop additional therapeutics to facilitate extended recovery from SUDs. The "hunger hormone" ghrelin acts by binding to the growth hormone secretagogue receptor 1α (GHS1αR) to control homeostatic and hedonic aspects of food intake and has been implicated in the mechanisms underlying SUDs. Preclinical studies indicate that GHS1αR antagonists and inverse agonists suppress reward-related signaling associated with cocaine and opioids. In the present study, we found that the GHS1αR antagonist JMV2959 was efficacious to suppress both cue-reinforced cocaine and oxycodone drug-seeking, but not cocaine or oxycodone self-administration in male Sprague-Dawley rats. These data suggest a role of the ghrelin-GHS1αR axis in mediating overlapping reward-related aspects of cocaine and oxycodone and premises the possibility that a GHS1αR antagonist may be a valuable therapeutic strategy for relapse vulnerability in SUDs.
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Affiliation(s)
- Christina R. Merritt
- Center for Addiction Sciences and Therapeutics and Department of Pharmacology and Toxicology, John Sealy School of Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - Erik J. Garcia
- Center for Addiction Sciences and Therapeutics and Department of Pharmacology and Toxicology, John Sealy School of Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - Victoria D. Brehm
- Center for Addiction Sciences and Therapeutics and Department of Pharmacology and Toxicology, John Sealy School of Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - Robert G. Fox
- Center for Addiction Sciences and Therapeutics and Department of Pharmacology and Toxicology, John Sealy School of Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - F. Gerard Moeller
- C. Kenneth and Dianne Wright Center for Clinical and Translational Research, Departments of Psychiatry and Pharmacology and Toxicology, Virginia Commonwealth University School of Medicine, Richmond, VA, United States
| | - Noelle C. Anastasio
- Center for Addiction Sciences and Therapeutics and Department of Pharmacology and Toxicology, John Sealy School of Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - Kathryn A. Cunningham
- Center for Addiction Sciences and Therapeutics and Department of Pharmacology and Toxicology, John Sealy School of Medicine, University of Texas Medical Branch, Galveston, TX, United States
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3
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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 DOI: 10.1016/j.physbeh.2023.114236] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [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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4
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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: 0] [Impact Index Per Article: 0] [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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5
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Involvement of the ghrelin system in the maintenance of oxycodone self-administration: converging evidence from endocrine, pharmacologic and transgenic approaches. Mol Psychiatry 2022; 27:2171-2181. [PMID: 35064236 PMCID: PMC9133122 DOI: 10.1038/s41380-022-01438-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 12/08/2021] [Accepted: 01/05/2022] [Indexed: 12/15/2022]
Abstract
Ghrelin, an orexigenic hormone, has emerged as a critical biological substrate implicated in drug reward. However, the response of the ghrelin system to opioid-motivated behaviors and the role of ghrelin in oxycodone self-administration remain to be studied. Here, we investigated the reciprocal interactions between the endogenous ghrelin system and oxycodone self-administration behaviors in rats and the role of the ghrelin system in brain stimulation reward (BSR) driven by optogenetic stimulation of midbrain reward circuits in mice. Oxycodone self-administration significantly elevated plasma ghrelin, des-acyl ghrelin and growth hormone and showed no effect on plasma LEAP2, a newly identified endogenous ghrelin receptor (GHS-R1a) antagonist. Oxycodone self-administration produced significant decreases in plasma gastric inhibitory polypeptide and insulin. Acquisition of oxycodone self-administration significantly upregulated GHS-R1a mRNA levels in dopamine neurons in the ventral tegmental area (VTA), a brain region critical in drug reward. Pretreatment with JMV2959, a selective GHS-R1a antagonist, dose-dependently reduced oxycodone self-administration and decreased the breakpoint for oxycodone under a progressive ratio reinforcement in Long-Evans rats. The inhibitory effects of JMV2959 on oxycodone self-administration is selectively mediated by GHS-R1a as JMV2959 showed a similar effect in Wistar wildtype but not in GHS-R knockout rats. JMV2959 pretreatment significantly inhibited BSR driven by selective stimulation of VTA dopamine neurons, but not by stimulation of striatal GABA neurons projecting to the VTA in mice. These findings suggest that elevation of ghrelin signaling by oxycodone or oxycodone-associated stimuli is a causal process by which oxycodone motivates oxycodone drug-taking and targeting the ghrelin system may be a viable treatment approach for opioid use disorders.
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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: 0] [Impact Index Per Article: 0] [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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7
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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: 2.0] [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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8
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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: 2.5] [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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9
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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: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 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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10
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Differential Influence of Pueraria lobata Root Extract and Its Main Isoflavones on Ghrelin Levels in Alcohol-Treated Rats. Pharmaceuticals (Basel) 2021; 15:ph15010025. [PMID: 35056082 PMCID: PMC8777655 DOI: 10.3390/ph15010025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/22/2021] [Accepted: 12/22/2021] [Indexed: 12/19/2022] Open
Abstract
The study was carried out on alcohol-preferring male Wistar rats. The following drugs were repeatedly (28×) administered: acamprosate (500 mg/kg, p.o.), naltrexone (0.1 mg/kg, i.p), and Pueraria lobata (kudzu) root extract (KU) (500 mg/kg, p.o.) and its isoflavones: daidzin (40 mg/kg, p.o.) and puerarin (150 mg/kg, p.o.). Their effects on a voluntary alcohol intake were assessed. KU and alcohol were also given for 9 days in an experiment on alcohol tolerance development. Finally, total and active ghrelin levels in peripheral blood serum were measured by ELISA method. Acamprosate, naltrexone, daidzin, and puerarin, reducing the alcohol intake, caused an increase in both forms of ghrelin levels. On the contrary, though KU inhibited the alcohol intake and alcohol tolerance development, it reduced ghrelin levels in alcohol-preferring rats. The changes of ghrelin concentration could play a role as an indicator of the currently used drugs. The other effect on the KU-induced shift in ghrelin levels in the presence of alcohol requires further detailed study.
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11
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Abstract
Addictive drugs are habit-forming. Addiction is a learned behavior; repeated exposure to addictive drugs can stamp in learning. Dopamine-depleted or dopamine-deleted animals have only unlearned reflexes; they lack learned seeking and learned avoidance. Burst-firing of dopamine neurons enables learning-long-term potentiation (LTP)-of search and avoidance responses. It sets the stage for learning that occurs between glutamatergic sensory inputs and GABAergic motor-related outputs of the striatum; this learning establishes the ability to search and avoid. Independent of burst-firing, the rate of single-spiking-or "pacemaker firing"-of dopaminergic neurons mediates motivational arousal. Motivational arousal increases during need states and its level determines the responsiveness of the animal to established predictive stimuli. Addictive drugs, while usually not serving as an external stimulus, have varying abilities to activate the dopamine system; the comparative abilities of different addictive drugs to facilitate LTP is something that might be studied in the future.
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Affiliation(s)
- Roy A Wise
- Intramural Research Program, National Institute on Drug Abuse, 250 Mason Lord Drive, Baltimore, MD, USA.
- Behavior Genetics Laboratory, McLean Hospital, Harvard Medical School, 115 Mill Street, Belmont, MA, 02478, USA.
| | - Chloe J Jordan
- Division of Alcohol, Drugs and Addiction, Department of Psychiatry, Harvard Medical School, McLean Hospital, 115 Mill Street, Belmont, MA, 02478, USA
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12
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Farrokhi R, Babapour V, Zendehdel M, Asghari A, Gilanpour H. Role of Dopaminergic and Cannabinoidergic Receptors on Ghrelin-Induced Hypophagia in 5-Day-Old Broiler Chicken. ARCHIVES OF RAZI INSTITUTE 2021; 76:935-948. [PMID: 35096329 PMCID: PMC8790998 DOI: 10.22092/ari.2020.351261.1514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 08/24/2020] [Indexed: 01/24/2023]
Abstract
The present study aimed to identify the role of dopaminergic and cannabinoidergic systems in the ghrelin-induced hypophagia among meat-type chickens. In the first experiment, intracerebroventricular (ICV) injection was applied to birds with control solution, D1 receptor antagonist (5 nmol), ghrelin (6 nmol), and D1 receptor antagonist plus ghrelin. The second to sixth experiments were similar to the first one, with the difference that D2 receptor antagonist (5 nmol), D3 receptor antagonist (6.4 nmol), D4 receptor antagonist (6 nmol), the precursor of dopamine (125 nmol), and 6-hydroxy dopamine (150 nmol) instead of D1 antagonist were injected into the broiler chickens. In experiment 7, control solution and different levels of ghrelin antagonists (5, 10, and 20 nmol) were injected. In experiment 8, the chickens were ICV injected with control solution, ghrelin antagonist (10 nmol), dopamine (40 nmol), and ghrelin antagonist plus dopamine. In experiments 9 and 10, CB1 and CB2 receptors antagonist (6.25µg and 5µg) were co-injected with ghrelin (6 nmol), respectively, measuring the food intake for 120 min after the injection. It was observed that ghrelin ICV injection considerably reduced food intake, whereas ghrelin antagonist increased food intake, depending on the dose (P<0.05). In addition, ghrelin-induced hypophagia was significantly attenuated by D1 receptor antagonist and 6-hydroxy dopamine (P<0.05), while the dopamine precursor considerably elevated the ghrelin-induced food intake (P<0.05). The dopamine-induced feeding behavior was diminished by the co-administration of [D-Lys-3]-GHRP-6 (10 nmol)+dopamine (40 nmol) (P<0.05). In addition, CB1 receptor antagonists enhanced the ghrelin influence on food intake (P<0.05). The results implied that the hypophagic impact of ghrelin was probably mediated by D1 and CB1 receptors within neonatal broilers.
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Affiliation(s)
- R Farrokhi
- Department of Basic Sciences, Faculty of Veterinary Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - V Babapour
- Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
| | - M Zendehdel
- Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
| | - A Asghari
- Department of Clinical Science, Faculty of Veterinary Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - H Gilanpour
- Department of Basic Sciences, Faculty of Veterinary Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran
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13
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Cornejo MP, Denis RGP, García Romero G, Fernández G, Reynaldo M, Luquet S, Perello M. Ghrelin treatment induces rapid and delayed increments of food intake: a heuristic model to explain ghrelin's orexigenic effects. Cell Mol Life Sci 2021; 78:6689-6708. [PMID: 34559253 PMCID: PMC11073221 DOI: 10.1007/s00018-021-03937-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 08/10/2021] [Accepted: 09/06/2021] [Indexed: 12/22/2022]
Abstract
Ghrelin is a stomach-derived peptide hormone with salient roles in the regulation of energy balance and metabolism. Notably, ghrelin is recognized as the most powerful known circulating orexigenic hormone. Here, we systematically investigated the effects of ghrelin on energy homeostasis and found that ghrelin primarily induces a biphasic effect on food intake that has indirect consequences on energy expenditure and nutrient partitioning. We also found that ghrelin-induced biphasic effect on food intake requires the integrity of Agouti-related peptide/neuropeptide Y-producing neurons of the hypothalamic arcuate nucleus, which seem to display a long-lasting activation after a single systemic injection of ghrelin. Finally, we found that different autonomic, hormonal and metabolic satiation signals transiently counteract ghrelin-induced food intake. Based on our observations, we propose a heuristic model to describe how the orexigenic effect of ghrelin and the anorectic food intake-induced rebound sculpt a timely constrain feeding response to ghrelin.
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Affiliation(s)
- María Paula Cornejo
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology, IMBICE, Argentine Research Council (CONICET), Scientific Research Commission of the Province of Buenos Aires (CIC-PBA) and National University of La Plata (UNLP), Calle 526 S/N entre 10 y 11, PO Box 403, 1900, La Plata, Buenos Aires, Argentina
| | - Raphaël G P Denis
- Unité de Biologie Fonctionnelle et Adaptative (BFA), UMR 8251, CNRS, Université de Paris, 75013, Paris, France
| | - Guadalupe García Romero
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology, IMBICE, Argentine Research Council (CONICET), Scientific Research Commission of the Province of Buenos Aires (CIC-PBA) and National University of La Plata (UNLP), Calle 526 S/N entre 10 y 11, PO Box 403, 1900, La Plata, Buenos Aires, Argentina
| | - Gimena Fernández
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology, IMBICE, Argentine Research Council (CONICET), Scientific Research Commission of the Province of Buenos Aires (CIC-PBA) and National University of La Plata (UNLP), Calle 526 S/N entre 10 y 11, PO Box 403, 1900, La Plata, Buenos Aires, Argentina
| | - Mirta Reynaldo
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology, IMBICE, Argentine Research Council (CONICET), Scientific Research Commission of the Province of Buenos Aires (CIC-PBA) and National University of La Plata (UNLP), Calle 526 S/N entre 10 y 11, PO Box 403, 1900, La Plata, Buenos Aires, Argentina
| | - Serge Luquet
- Unité de Biologie Fonctionnelle et Adaptative (BFA), UMR 8251, CNRS, Université de Paris, 75013, Paris, France
| | - Mario Perello
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology, IMBICE, Argentine Research Council (CONICET), Scientific Research Commission of the Province of Buenos Aires (CIC-PBA) and National University of La Plata (UNLP), Calle 526 S/N entre 10 y 11, PO Box 403, 1900, La Plata, Buenos Aires, Argentina.
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14
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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: 19] [Impact Index Per Article: 6.3] [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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15
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Falo CP, Benitez R, Caro M, Morell M, Forte-Lago I, Hernandez-Cortes P, Sanchez-Gonzalez C, O’Valle F, Delgado M, Gonzalez-Rey E. The Neuropeptide Cortistatin Alleviates Neuropathic Pain in Experimental Models of Peripheral Nerve Injury. Pharmaceutics 2021; 13:pharmaceutics13070947. [PMID: 34202793 PMCID: PMC8309056 DOI: 10.3390/pharmaceutics13070947] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/18/2021] [Accepted: 06/21/2021] [Indexed: 12/25/2022] Open
Abstract
Neuropathic pain is one of the most severe forms of chronic pain caused by the direct injury of the somatosensory system. The current drugs for treating neuropathies have limited efficacies or show important side effects, and the development of analgesics with novel modes of action is critical. The identification of endogenous anti-nociceptive factors has emerged as an attractive strategy for designing new pharmacological approaches to treat neuropathic pain. Cortistatin is a neuropeptide with potent anti-inflammatory activity, recently identified as a natural analgesic peptide in several models of pain evoked by inflammatory conditions. Here, we investigated the potential analgesic effect of cortistatin in neuropathic pain using a variety of experimental models of peripheral nerve injury caused by chronic constriction or partial transection of the sciatic nerve or by diabetic neuropathy. We found that the peripheral and central injection of cortistatin ameliorated hyperalgesia and allodynia, two of the dominant clinical manifestations of chronic neuropathic pain. Cortistatin-induced analgesia was multitargeted, as it regulated the nerve damage-induced hypersensitization of primary nociceptors, inhibited neuroinflammatory responses, and enhanced the production of neurotrophic factors both at the peripheral and central levels. We also demonstrated the neuroregenerative/protective capacity of cortistatin in a model of severe peripheral nerve transection. Interestingly, the nociceptive system responded to nerve injury by secreting cortistatin, and a deficiency in cortistatin exacerbated the neuropathic pain responses and peripheral nerve dysfunction. Therefore, cortistatin-based therapies emerge as attractive alternatives for treating chronic neuropathic pain of different etiologies.
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Affiliation(s)
- Clara P. Falo
- Institute of Parasitology and Biomedicine Lopez-Neyra, IPBLN-CSIC, Parque Tecnologico de la Salud, 18016 Granada, Spain; (C.P.F.); (R.B.); (M.C.); (M.M.); (I.F.-L.); (C.S.-G.)
| | - Raquel Benitez
- Institute of Parasitology and Biomedicine Lopez-Neyra, IPBLN-CSIC, Parque Tecnologico de la Salud, 18016 Granada, Spain; (C.P.F.); (R.B.); (M.C.); (M.M.); (I.F.-L.); (C.S.-G.)
| | - Marta Caro
- Institute of Parasitology and Biomedicine Lopez-Neyra, IPBLN-CSIC, Parque Tecnologico de la Salud, 18016 Granada, Spain; (C.P.F.); (R.B.); (M.C.); (M.M.); (I.F.-L.); (C.S.-G.)
| | - Maria Morell
- Institute of Parasitology and Biomedicine Lopez-Neyra, IPBLN-CSIC, Parque Tecnologico de la Salud, 18016 Granada, Spain; (C.P.F.); (R.B.); (M.C.); (M.M.); (I.F.-L.); (C.S.-G.)
- Genyo Center for Genomics and Oncological Research, Parque Tecnologico de la Salud, 18016 Granada, Spain
| | - Irene Forte-Lago
- Institute of Parasitology and Biomedicine Lopez-Neyra, IPBLN-CSIC, Parque Tecnologico de la Salud, 18016 Granada, Spain; (C.P.F.); (R.B.); (M.C.); (M.M.); (I.F.-L.); (C.S.-G.)
| | - Pedro Hernandez-Cortes
- Department of Orthopedic Surgery, San Cecilio University Hospital, 18071 Granada, Spain;
| | - Clara Sanchez-Gonzalez
- Institute of Parasitology and Biomedicine Lopez-Neyra, IPBLN-CSIC, Parque Tecnologico de la Salud, 18016 Granada, Spain; (C.P.F.); (R.B.); (M.C.); (M.M.); (I.F.-L.); (C.S.-G.)
| | - Francisco O’Valle
- Department of Pathology, School of Medicine, IBIMER and IBS-Granada, Granada University, 18016 Granada, Spain;
| | - Mario Delgado
- Institute of Parasitology and Biomedicine Lopez-Neyra, IPBLN-CSIC, Parque Tecnologico de la Salud, 18016 Granada, Spain; (C.P.F.); (R.B.); (M.C.); (M.M.); (I.F.-L.); (C.S.-G.)
- Correspondence: (M.D.); (E.G.-R.)
| | - Elena Gonzalez-Rey
- Institute of Parasitology and Biomedicine Lopez-Neyra, IPBLN-CSIC, Parque Tecnologico de la Salud, 18016 Granada, Spain; (C.P.F.); (R.B.); (M.C.); (M.M.); (I.F.-L.); (C.S.-G.)
- Correspondence: (M.D.); (E.G.-R.)
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16
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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: 11] [Impact Index Per Article: 3.7] [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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17
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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: 2.8] [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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18
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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: 12] [Impact Index Per Article: 3.0] [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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19
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Sustkova‐Fiserova M, Puskina N, Havlickova T, Lapka M, Syslova K, Pohorala V, Charalambous C. Ghrelin receptor antagonism of fentanyl-induced conditioned place preference, intravenous self-administration, and dopamine release in the nucleus accumbens in rats. Addict Biol 2020; 25:e12845. [PMID: 31696597 DOI: 10.1111/adb.12845] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 09/26/2019] [Accepted: 10/02/2019] [Indexed: 12/22/2022]
Abstract
The extended occurrence of fentanils abuse associated with the dramatic increase in opioid fatal overdoses and dependence strongly emphasizes insufficiencies in opioid addiction treatment. Recently, the growth hormone secretagogue receptor (GHS-R1A) antagonism was proposed as a promising mechanism for drug addiction therapy. However, the role of GHS-R1A and its endogenous ligand ghrelin in opioid abuse is still unclear. Therefore, the aim of our study was to clarify whether the GHS-R1A antagonist JMV2959 could reduce the fentanyl-induced conditioned place preference (CPP), the fentanyl intravenous self-administration (IVSA), and the tendency to relapse, but also whether JMV2959 could significantly influence the fentanyl-induced dopamine efflux in the nucleus accumbens (NAC) in rats, that importantly participates in opioids' reinforcing effects. Following an ongoing fentanyl self-administration, JMV2959 3 mg/kg was administered intraperitoneally 20 minutes before three consequent daily 360-minute IVSA sessions under a fixed ratio FR1, which significantly reduced the number of active lever-pressing, the number of infusions, and the fentanyl intake. Pretreatment with JMV2959 also reduced the fentanyl-seeking/relapse-like behaviour tested in rats on the 12th day of the forced abstinence period. Pretreatment with JMV2959 significantly and dose-dependently reduced the manifestation of fentanyl-CPP. The fentanyl-CPP development was reduced after the simultaneous administration of JMV2959 with fentanyl during conditioning. The JMV2959 significantly reduced the accumbens dopamine release induced by subcutaneous and intravenous fentanyl. Simultaneously, it affected the concentration of byproducts associated with dopamine metabolism in the NAC. Our findings suggest that GHS-R1A importantly participates in the rewarding/reinforcing effects of fentanyl.
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Affiliation(s)
| | - Nina Puskina
- Department of Addictology First Faculty of Medicine Charles University Czech Republic
| | - Tereza Havlickova
- Department of Pharmacology, Third Faculty of Medicine Charles University Czech Republic
| | - Marek Lapka
- Department of Pharmacology, Third Faculty of Medicine Charles University Czech Republic
| | - Kamila Syslova
- Laboratory of Medicinal Diagnostics Department of Organic Technology ICT Czech Republic
| | - Veronika Pohorala
- Department of Pharmacology, Third Faculty of Medicine Charles University Czech Republic
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Abstract
Addiction is commonly identified with habitual nonmedical self-administration of drugs. It is usually defined by characteristics of intoxication or by characteristics of withdrawal symptoms. Such addictions can also be defined in terms of the brain mechanisms they activate; most addictive drugs cause elevations in extracellular levels of the neurotransmitter dopamine. Animals unable to synthesize or use dopamine lack the conditioned reflexes discussed by Pavlov or the appetitive behavior discussed by Craig; they have only unconditioned consummatory reflexes. Burst discharges (phasic firing) of dopamine-containing neurons are necessary to establish long-term memories associating predictive stimuli with rewards and punishers. Independent discharges of dopamine neurons (tonic or pacemaker firing) determine the motivation to respond to such cues. As a result of habitual intake of addictive drugs, dopamine receptors expressed in the brain are decreased, thereby reducing interest in activities not already stamped in by habitual rewards.
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Affiliation(s)
- Roy A Wise
- National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland 21224, USA; .,Behavioral Genetics Laboratory, McLean Hospital, Belmont, Massachusetts 02478, USA;
| | - Mykel A Robble
- Behavioral Genetics Laboratory, McLean Hospital, Belmont, Massachusetts 02478, USA;
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21
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Serrenho D, Santos SD, Carvalho AL. The Role of Ghrelin in Regulating Synaptic Function and Plasticity of Feeding-Associated Circuits. Front Cell Neurosci 2019; 13:205. [PMID: 31191250 PMCID: PMC6546032 DOI: 10.3389/fncel.2019.00205] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Accepted: 04/24/2019] [Indexed: 12/21/2022] Open
Abstract
Synaptic plasticity of the neuronal circuits associated with feeding behavior is regulated by peripheral signals as a response to changes in the energy status of the body. These signals include glucose, free fatty acids, leptin and ghrelin and are released into circulation, being able to reach the brain. Ghrelin, a small peptide released from the stomach, is an orexigenic hormone produced in peripheral organs, and its action regulates food intake, body weight and glucose homeostasis. Behavioral studies show that ghrelin is implicated in the regulation of both hedonic and homeostatic feeding and of cognition. Ghrelin-induced synaptic plasticity has been described in neuronal circuits associated with these behaviors. In this review, we discuss the neuromodulatory mechanisms induced by ghrelin in regulating synaptic plasticity in three main neuronal circuits previously associated with feeding behaviors, namely hypothalamic (homeostatic feeding), ventral tegmental (hedonic and motivational feeding) and hippocampal (cognitive) circuits. Given the central role of ghrelin in regulating feeding behaviors, and the altered ghrelin levels associated with metabolic disorders such as obesity and anorexia, it is of paramount relevance to understand the effects of ghrelin on synaptic plasticity of neuronal circuits associated with feeding behaviors.
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Affiliation(s)
- Débora Serrenho
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal.,Institute for Interdisciplinary Research (IIIUC), University of Coimbra, Coimbra, Portugal.,PhD Program in Experimental Biology and Biomedicine (PDBEB), University of Coimbra, Coimbra, Portugal
| | - Sandra D Santos
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal.,Institute for Interdisciplinary Research (IIIUC), University of Coimbra, Coimbra, Portugal
| | - Ana Luísa Carvalho
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal.,Department of Life Sciences, University of Coimbra, Coimbra, Portugal
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22
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Kalafateli AL, Vallöf D, Jerlhag E. Activation of amylin receptors attenuates alcohol-mediated behaviours in rodents. Addict Biol 2019; 24:388-402. [PMID: 29405517 PMCID: PMC6585842 DOI: 10.1111/adb.12603] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 12/14/2017] [Accepted: 01/05/2018] [Indexed: 02/06/2023]
Abstract
Alcohol expresses its reinforcing properties by activating areas of the mesolimbic dopamine system, which consists of dopaminergic neurons projecting from the ventral tegmental area to the nucleus accumbens. The findings that reward induced by food and addictive drugs involve common mechanisms raise the possibility that gut-brain hormones, which control appetite, such as amylin, could be involved in reward regulation. Amylin decreases food intake, and despite its implication in the regulation of natural rewards, tenuous evidence support amylinergic mediation of artificial rewards, such as alcohol. Therefore, the present experiments were designed to investigate the effect of salmon calcitonin (sCT), an amylin receptor agonist and analogue of endogenous amylin, on various alcohol-related behaviours in rodents. We showed that acute sCT administration attenuated the established effects of alcohol on the mesolimbic dopamine system, particularly alcohol-induced locomotor stimulation and accumbal dopamine release. Using the conditioned place preference model, we demonstrated that repeated sCT administration prevented the expression of alcohol's rewarding properties and that acute sCT administration blocked the reward-dependent memory consolidation. In addition, sCT pre-treatment attenuated alcohol intake in low alcohol-consuming rats, with a more evident decrease in high alcohol consumers in the intermittent alcohol access model. Lastly, sCT did not alter peanut butter intake, blood alcohol concentration and plasma corticosterone levels in mice. Taken together, the present data support that amylin signalling is involved in the expression of alcohol reinforcement and that amylin receptor agonists could be considered for the treatment of alcohol use disorder in humans.
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Affiliation(s)
- Aimilia Lydia Kalafateli
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of Gothenburg Gothenburg Sweden
| | - Daniel Vallöf
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of Gothenburg Gothenburg Sweden
| | - Elisabet Jerlhag
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of Gothenburg Gothenburg Sweden
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23
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Jerlhag E. Gut-brain axis and addictive disorders: A review with focus on alcohol and drugs of abuse. Pharmacol Ther 2018; 196:1-14. [PMID: 30439457 DOI: 10.1016/j.pharmthera.2018.11.005] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Due to the limited efficacy of existing medications for addictive disorders including alcohol use disorder (AUD), the need for additional medications is substantial. Potential new medications for addiction can be identified through investigation of the neurochemical substrates mediating the ability of drugs of abuse such as alcohol to activate the mesolimbic dopamine system. Interestingly, recent studies implicate neuropeptides of the gut-brain axis as modulators of reward and addiction processes. The present review therefore summarizes the current studies investigating the ability of the gut-brain peptides ghrelin, glucagon-like peptide-1 (GLP-1), amylin and neuromedin U (NMU) to modulate alcohol- and drug-related behaviors in rodents and humans. Extensive literature demonstrates that ghrelin, the only known orexigenic neuropeptide to date, enhances reward as well as the intake of alcohol, and other drugs of abuse, while ghrelin receptor antagonism has the opposite effects. On the other hand, the anorexigenic peptides GLP-1, amylin and NMU independently inhibits reward from alcohol and drugs of abuse in rodents. Collectively, these rodent and human studies imply that central ghrelin, GLP-1, amylin and NMU signaling may contribute to addiction processes. Therefore, the need for randomized clinical trials investigating the effects of agents targeting these aforementioned systems on drug/alcohol use is substantial.
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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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Cornejo MP, Barrile F, De Francesco PN, Portiansky EL, Reynaldo M, Perello M. Ghrelin Recruits Specific Subsets of Dopamine and GABA Neurons of Different Ventral Tegmental Area Sub-nuclei. Neuroscience 2018; 392:107-120. [DOI: 10.1016/j.neuroscience.2018.09.027] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 09/10/2018] [Accepted: 09/19/2018] [Indexed: 11/30/2022]
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25
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Havlickova T, Charalambous C, Lapka M, Puskina N, Jerabek P, Sustkova-Fiserova M. Ghrelin Receptor Antagonism of Methamphetamine-Induced Conditioned Place Preference and Intravenous Self-Administration in Rats. Int J Mol Sci 2018; 19:ijms19102925. [PMID: 30261633 PMCID: PMC6213741 DOI: 10.3390/ijms19102925] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 09/15/2018] [Accepted: 09/24/2018] [Indexed: 02/06/2023] Open
Abstract
Methamphetamine abuse imposes a significant burden on individuals and society worldwide, and an effective therapy of methamphetamine addiction would provide distinguished social benefits. Ghrelin significantly participates in reinforcing neurobiological mechanisms of stimulants, including amphetamines; thus, ghrelin antagonism is proposed as a promising addiction treatment. The aim of our study was to elucidate whether the pretreatment with growth hormone secretagogue receptor (GHS-R1A) antagonist, substance JMV2959, could reduce the methamphetamine intravenous self-administration (IVSA) and the tendency to relapse, and whether JMV2959 could reduce or prevent methamphetamine-induced conditioned place preference (CPP) in rats. Following an adequate maintenance period, JMV2959 3 mg/kg was administered intraperitoneally 20 min before three consequent daily 180 min sessions of methamphetamine IVSA under a fixed ratio FR1, which significantly reduced the number of active lever-pressings, the number of infusions, and the amount of the consumed methamphetamine dose. Pretreatment with JMV2959 also reduced or prevented relapse-like behavior tested in rats on the 12th day of the abstinence period. Pretreatment with JMV2959 significantly reduced the expression of methamphetamine-induced CPP. Simultaneous administration of JMV2959 with methamphetamine during the conditioning period significantly reduced the methamphetamine-CPP. Our results encourage further research of the ghrelin antagonism as a potential new pharmacological tool for methamphetamine addiction treatment.
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Affiliation(s)
- Tereza Havlickova
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 1010034 Prague, Czech Republic.
| | - Chrysostomos Charalambous
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 1010034 Prague, Czech Republic.
| | - Marek Lapka
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 1010034 Prague, Czech Republic.
| | - Nina Puskina
- Department of Addictology, First Faculty of Medicine, Charles University, Apolinarska 4, 212800 Prague, Czech Republic.
| | - Pavel Jerabek
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 1010034 Prague, Czech Republic.
| | - Magdalena Sustkova-Fiserova
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 1010034 Prague, Czech Republic.
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Morris LS, Voon V, Leggio L. Stress, Motivation, and the Gut-Brain Axis: A Focus on the Ghrelin System and Alcohol Use Disorder. Alcohol Clin Exp Res 2018; 42:10.1111/acer.13781. [PMID: 29797564 PMCID: PMC6252147 DOI: 10.1111/acer.13781] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 05/17/2018] [Indexed: 01/04/2023]
Abstract
Since its discovery, the gut hormone, ghrelin, has been implicated in diverse functional roles in the central nervous system. Central and peripheral interactions between ghrelin and other hormones, including the stress-response hormone cortisol, govern complex behavioral responses to external cues and internal states. By acting at ventral tegmental area dopaminergic projections and other areas involved in reward processing, ghrelin can induce both general and directed motivation for rewards, including craving for alcohol and other alcohol-seeking behaviors. Stress-induced increases in cortisol seem to increase ghrelin in the periphery, suggesting a pathway by which ghrelin influences how stressful life events trigger motivation for rewards. However, in some states, ghrelin may be protective against the anxiogenic effects of stressors. This critical review brings together a dynamic and growing literature, that is, at times inconsistent, on the relationships between ghrelin, central reward-motivation pathways, and central and peripheral stress responses, with a special focus on its emerging role in the context of alcohol use disorder.
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Affiliation(s)
- Laurel S. Morris
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, UK
- Department of Psychology, University of Cambridge, UK
- Mood and Anxiety Disorders Program, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Valerie Voon
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, UK
- Department of Psychiatry, University of Cambridge, UK
| | - Lorenzo Leggio
- Section on Clinical Psychoneuroendocrinology and Neuropsychopharmacology, National Institute on Alcohol Abuse and Alcoholism and National Institute on Drug Abuse, National Institutes of Health, Bethesda, MD, USA
- Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, Brown University, Providence, RI, USA
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Jang JK, Kim WY, Cho BR, Lee JW, Kim JH. Locomotor sensitization is expressed by ghrelin and D1 dopamine receptor agonist in the nucleus accumbens core in amphetamine pre-exposed rat. Addict Biol 2018. [PMID: 28635134 DOI: 10.1111/adb.12533] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Ghrelin modulates mesolimbic dopaminergic pathways in the brain in addition to its role in feeding. We investigated what roles ghrelin in the nucleus accumbens (NAcc) core may play in mediating locomotor activating effects of amphetamine (AMPH). First, when rats were administered with AMPH (1 mg/kg, i.p.) following a bilateral microinjection of ghrelin (0.1 or 0.5 μg/side) into the NAcc core, their locomotor activity was significantly enhanced, while these effects were blocked by co-microinjection of ghrelin receptor antagonist (0.5 μg/side) into this site. Second, we pre-exposed rats to saline or amphetamine (1 mg/kg, i.p.) every 2 to 3 days for a total of four times. After 2 weeks of drug-free withdrawal period, we examined the effect of saline, ghrelin (0.5 μg/side), D1 dopamine receptor agonist, SKF81297 (0.5 μg/side) or ghrelin (0.5 μg/side) + SKF81297 (0.5 μg/side) directly microinjected into the NAcc core on locomotor activity. When we measured rats' locomotor activity for 1 hour immediately following microinjections, only ghrelin + SKF81297 produces sensitized locomotor activity, while all others have no effects. These results suggest that ghrelin may have a distinct role in the NAcc core to provoke the sensitized locomotor activity induced by psychomotor stimulants, and further, it may produce these effects by interaction with D1 dopamine receptors.
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Affiliation(s)
- Ju Kyong Jang
- Department of Physiology, Brain Korea 21 Plus Project for Medical Science; Brain Research Institute, Yonsei University College of Medicine; Seoul South Korea
| | - Wha Young Kim
- Department of Physiology, Brain Korea 21 Plus Project for Medical Science; Brain Research Institute, Yonsei University College of Medicine; Seoul South Korea
| | - Bo Ram Cho
- Department of Physiology, Brain Korea 21 Plus Project for Medical Science; Brain Research Institute, Yonsei University College of Medicine; Seoul South Korea
| | - Jung Won Lee
- Department of Physiology, Brain Korea 21 Plus Project for Medical Science; Brain Research Institute, Yonsei University College of Medicine; Seoul South Korea
| | - Jeong-Hoon Kim
- Department of Physiology, Brain Korea 21 Plus Project for Medical Science; Brain Research Institute, Yonsei University College of Medicine; Seoul South Korea
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Coccurello R, Maccarrone M. Hedonic Eating and the "Delicious Circle": From Lipid-Derived Mediators to Brain Dopamine and Back. Front Neurosci 2018; 12:271. [PMID: 29740277 PMCID: PMC5928395 DOI: 10.3389/fnins.2018.00271] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 04/09/2018] [Indexed: 01/09/2023] Open
Abstract
Palatable food can be seductive and hedonic eating can become irresistible beyond hunger and negative consequences. This is witnessed by the subtle equilibrium between eating to provide energy intake for homeostatic functions, and reward-induced overeating. In recent years, considerable efforts have been devoted to study neural circuits, and to identify potential factors responsible for the derangement of homeostatic eating toward hedonic eating and addiction-like feeding behavior. Here, we examined recent literature on “old” and “new” players accountable for reward-induced overeating and possible liability to eating addiction. Thus, the role of midbrain dopamine is positioned at the intersection between selected hormonal signals involved in food reward information processing (namely, leptin, ghrelin, and insulin), and lipid-derived neural mediators such as endocannabinoids. The impact of high fat palatable food and dietary lipids on endocannabinoid formation is reviewed in its pathogenetic potential for the derangement of feeding homeostasis. Next, endocannabinoid signaling that regulates synaptic plasticity is discussed as a key mechanism acting both at hypothalamic and mesolimbic circuits, and affecting both dopamine function and interplay between leptin and ghrelin signaling. Outside the canonical hypothalamic feeding circuits involved in energy homeostasis and the notion of “feeding center,” we focused on lateral hypothalamus as neural substrate able to confront food-associated homeostatic information with food salience, motivation to eat, reward-seeking, and development of compulsive eating. Thus, the lateral hypothalamus-ventral tegmental area-nucleus accumbens neural circuitry is reexamined in order to interrogate the functional interplay between ghrelin, dopamine, orexin, and endocannabinoid signaling. We suggested a pivotal role for endocannabinoids in food reward processing within the lateral hypothalamus, and for orexin neurons to integrate endocrine signals with food reinforcement and hedonic eating. In addition, the role played by different stressors in the reinstatement of preference for palatable food and food-seeking behavior is also considered in the light of endocannabinoid production, activation of orexin receptors and disinhibition of dopamine neurons. Finally, type-1 cannabinoid receptor-dependent inhibition of GABA-ergic release and relapse to reward-associated stimuli is linked to ghrelin and orexin signaling in the lateral hypothalamus-ventral tegmental area-nucleus accumbens network to highlight its pathological potential for food addiction-like behavior.
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Affiliation(s)
- Roberto Coccurello
- Department of Biomedical Sciences, Institute of Cell Biology and Neurobiology, National Research Council, Rome, Italy.,Laboratory of Neurochemistry of Lipids, European Center for Brain Research (CERC), IRRCS Santa Lucia Foundation, Rome, Italy
| | - Mauro Maccarrone
- Laboratory of Neurochemistry of Lipids, European Center for Brain Research (CERC), IRRCS Santa Lucia Foundation, Rome, Italy.,Department of Medicine, Campus Bio-Medico University of Rome, Rome, Italy
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Koopmann A, Schuster R, Kiefer F. The impact of the appetite-regulating, orexigenic peptide ghrelin on alcohol use disorders: A systematic review of preclinical and clinical data. Biol Psychol 2018; 131:14-30. [DOI: 10.1016/j.biopsycho.2016.12.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 10/13/2016] [Accepted: 12/15/2016] [Indexed: 12/13/2022]
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Kalafateli AL, Vallöf D, Jörnulf JW, Heilig M, Jerlhag E. A cannabinoid receptor antagonist attenuates ghrelin-induced activation of the mesolimbic dopamine system in mice. Physiol Behav 2017; 184:211-219. [PMID: 29221808 DOI: 10.1016/j.physbeh.2017.12.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 12/04/2017] [Accepted: 12/05/2017] [Indexed: 01/26/2023]
Abstract
Ghrelin has been attributed various physiological processes including food intake and reward regulation, through activation of the mesolimbic dopamine system. Reward modulation involves the mesolimbic dopamine system, consisting of the ventral tegmental area (VTA) dopamine neurons targeting nucleus accumbens (NAc), a system that ghrelin activates through VTA-dependent mechanisms. In the first study, we found that systemic intraperitoneal (ip) administration of rimonabant attenuated intracerebroventricular (icv) ghrelin's ability to cause locomotor stimulation and NAc dopamine release in mice. Ghrelin-induced (icv) chow intake was not altered by rimonabant administration (ip). Finally, we showed that bilateral VTA administration of rimonabant blocks the ability of intra-VTA administered ghrelin to increase locomotor activity, but does not affect food intake in mice. Collectively, these data indicate clear dissociation between regulation of food intake and activation of the mesolimbic dopamine system.
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Affiliation(s)
- Aimilia Lydia Kalafateli
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Daniel Vallöf
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Julia Winsa Jörnulf
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Markus Heilig
- Center for Social and Affective Neuroscience, Division of Neuro and Inflammation Sciences, Linköping University, Linköping, 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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31
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Sustkova-Fiserova M, Charalambous C, Havlickova T, Lapka M, Jerabek P, Puskina N, Syslova K. Alterations in Rat Accumbens Endocannabinoid and GABA Content during Fentanyl Treatment: The Role of Ghrelin. Int J Mol Sci 2017; 18:E2486. [PMID: 29165386 PMCID: PMC5713452 DOI: 10.3390/ijms18112486] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 11/07/2017] [Accepted: 11/17/2017] [Indexed: 12/20/2022] Open
Abstract
The opioid-induced rise of extracellular dopamine, endocannabinoid anandamide and γ-aminobutyric acid (GABA) concentrations triggered by opioids in the nucleus accumbens shell (NACSh) most likely participate in opioid reward. We have previously demonstrated that systemic administration of ghrelin antagonist (JMV2959) significantly decreased morphine-induced dopamine and anandamide (N-arachidonoylethanolamine, AEA) increase in the NACSh. Fentanyl is considered as a µ-receptor-selective agonist. The aim of this study was to test whether JMV2959, a growth hormone secretagogue receptor (GHS-R1A) antagonist, can influence the fentanyl-induced effects on anandamide, 2-arachidonoylglycerol (2-AG) and GABA in the NACSh and specify the involvement of GHS-R1A located in the ventral tegmental area (VTA) and nucleus accumbens (NAC). Using in vivo microdialysis in rats, we have found that pre-treatment with JMV2959 reversed dose dependently fentanyl-induced anandamide increases in the NACSh, resulting in a significant AEA decrease and intensified fentanyl-induced decreases in accumbens 2-AG levels, with both JMV2959 effects more expressed when administered into the NACSh in comparison to the VTA. JMV2959 pre-treatment significantly decreased the fentanyl-evoked accumbens GABA efflux and reduced concurrently monitored fentanyl-induced behavioural stimulation. Our current data encourage further investigation to assess if substances affecting GABA or endocannabinoid concentrations and action, such as GHS-R1A antagonists, can be used to prevent opioid-seeking behaviour.
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Affiliation(s)
- Magdalena Sustkova-Fiserova
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 100 34 Prague 10, Czech Republic; (C.C.); (T.H.); (M.L.); (P.J.)
| | - Chrysostomos Charalambous
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 100 34 Prague 10, Czech Republic; (C.C.); (T.H.); (M.L.); (P.J.)
| | - Tereza Havlickova
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 100 34 Prague 10, Czech Republic; (C.C.); (T.H.); (M.L.); (P.J.)
| | - Marek Lapka
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 100 34 Prague 10, Czech Republic; (C.C.); (T.H.); (M.L.); (P.J.)
| | - Pavel Jerabek
- Department of Pharmacology, Third Faculty of Medicine, Charles University, Ruska 87, 100 34 Prague 10, Czech Republic; (C.C.); (T.H.); (M.L.); (P.J.)
| | - Nina Puskina
- Department of Addictology, First Faculty of Medicine, Charles University, Apolinarska 4, 128 00 Prague 2, Czech Republic;
| | - Kamila Syslova
- Laboratory of Medicinal Diagnostics, Department of Organic Technology ICT, Technicka 5, 166 28 Prague 6, Czech Republic;
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32
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Ghrelin receptor antagonism of morphine-induced conditioned place preference and behavioral and accumbens dopaminergic sensitization in rats. Neurochem Int 2017; 110:101-113. [DOI: 10.1016/j.neuint.2017.09.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 08/17/2017] [Accepted: 09/24/2017] [Indexed: 01/06/2023]
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33
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Stievenard A, Méquinion M, Andrews ZB, Destée A, Chartier-Harlin MC, Viltart O, Vanbesien-Mailliot CC. Is there a role for ghrelin in central dopaminergic systems? Focus on nigrostriatal and mesocorticolimbic pathways. Neurosci Biobehav Rev 2017; 73:255-275. [DOI: 10.1016/j.neubiorev.2016.11.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 11/23/2016] [Accepted: 11/25/2016] [Indexed: 12/21/2022]
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34
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Yalcin O, Iseri E, Bukan N, Ercin U. Effects of Long Acting Methylphenidate on Ghrelin Levels in Male Children with Attention Deficit Hyperactivity Disorder: An Open Label Trial. ACTA ACUST UNITED AC 2016. [DOI: 10.5455/bcp.20130708042604] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Ozhan Yalcin
- Bakirkoy Training and Research Hospital for Mental Disorders and Neurological Diseases, Istanbul - Turkey
| | - Elvan Iseri
- Gazi University School of Medicine, Department of Child and Adolescent Psychiatry, Ankara - Turkey
| | - Neslihan Bukan
- Gazi University School of Medicine, Department of Medical Biochemistry, Ankara - Turkey
| | - Ugur Ercin
- Gazi University School of Medicine, Department of Medical Biochemistry, Ankara - Turkey
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35
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Wang J, Zhao J, Liu Z, Guo F, Wang Y, Wang X, Zhang R, Vreugdenhil M, Lu C. Acute Ethanol Inhibition of γ Oscillations Is Mediated by Akt and GSK3β. Front Cell Neurosci 2016; 10:189. [PMID: 27582689 PMCID: PMC4987361 DOI: 10.3389/fncel.2016.00189] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Accepted: 07/19/2016] [Indexed: 01/23/2023] Open
Abstract
Hippocampal network oscillations at gamma band frequency (γ, 30-80 Hz) are closely associated with higher brain functions such as learning and memory. Acute ethanol exposure at intoxicating concentrations (≥50 mM) impairs cognitive function. This study aimed to determine the effects and the mechanisms of acute ethanol exposure on γ oscillations in an in vitro model. Ethanol (25-100 mM) suppressed kainate-induced γ oscillations in CA3 area of the rat hippocampal slices, in a concentration-dependent, reversible manner. The ethanol-induced suppression was reduced by the D1R antagonist SCH23390 or the PKA inhibitor H89, was prevented by the Akt inhibitor triciribine or the GSk3β inhibitor SB415286, was enhanced by the NMDA receptor antagonist D-AP5, but was not affected by the MAPK inhibitor U0126 or PI3K inhibitor wortmanin. Our results indicate that the intracellular kinases Akt and GSk3β play a critical role in the ethanol-induced suppression of γ oscillations and reveal new cellular pathways involved in the ethanol-induced cognitive impairment.
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Affiliation(s)
- JianGang Wang
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical UniversityXinxiang, China; Department of Pathophysiology, Xinxiang Medical UniversityXinxiang, China
| | - JingXi Zhao
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical UniversityXinxiang, China; Psychiatric Hospital of Henan ProvinceXinxiang, China
| | - ZhiHua Liu
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical UniversityXinxiang, China; Psychiatric Hospital of Henan ProvinceXinxiang, China
| | - FangLi Guo
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical UniversityXinxiang, China; Department of Neurobiology and Physiology, Xinxiang Medical UniversityXinxiang, China
| | - Yali Wang
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical UniversityXinxiang, China; Department of Neurobiology and Physiology, Xinxiang Medical UniversityXinxiang, China
| | - Xiaofang Wang
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical University Xinxiang, China
| | - RuiLing Zhang
- Psychiatric Hospital of Henan Province Xinxiang, China
| | - Martin Vreugdenhil
- Department of Psychology, Xinxiang Medical UniversityHenan, China; Department of Health Sciences, Birmingham City UniversityBirmingham, UK
| | - Chengbiao Lu
- Key Laboratory for the Brain Research of Henan Province, Xinxiang Medical UniversityXinxiang, China; Psychiatric Hospital of Henan ProvinceXinxiang, China
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36
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Edwards A, Abizaid A. Driving the need to feed: Insight into the collaborative interaction between ghrelin and endocannabinoid systems in modulating brain reward systems. Neurosci Biobehav Rev 2016; 66:33-53. [PMID: 27136126 DOI: 10.1016/j.neubiorev.2016.03.032] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 03/08/2016] [Accepted: 03/31/2016] [Indexed: 01/29/2023]
Abstract
Independent stimulation of either the ghrelin or endocannabinoid system promotes food intake and increases adiposity. Given the similar distribution of their receptors in feeding associated brain regions and organs involved in metabolism, it is not surprising that evidence of their interaction and its importance in modulating energy balance has emerged. This review documents the relationship between ghrelin and endocannabinoid systems within the periphery and hypothalamus (HYP) before presenting evidence suggesting that these two systems likewise work collaboratively within the ventral tegmental area (VTA) to modulate non-homeostatic feeding. Mechanisms, consistent with current evidence and local infrastructure within the VTA, will be proposed.
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Affiliation(s)
- Alexander Edwards
- Department of Neuroscience, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada.
| | - Alfonso Abizaid
- Department of Neuroscience, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada.
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37
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Bell RL, Hauser S, Rodd ZA, Liang T, Sari Y, McClintick J, Rahman S, Engleman EA. A Genetic Animal Model of Alcoholism for Screening Medications to Treat Addiction. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2016; 126:179-261. [PMID: 27055615 PMCID: PMC4851471 DOI: 10.1016/bs.irn.2016.02.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The purpose of this review is to present up-to-date pharmacological, genetic, and behavioral findings from the alcohol-preferring P rat and summarize similar past work. Behaviorally, the focus will be on how the P rat meets criteria put forth for a valid animal model of alcoholism with a highlight on its use as an animal model of polysubstance abuse, including alcohol, nicotine, and psychostimulants. Pharmacologically and genetically, the focus will be on the neurotransmitter and neuropeptide systems that have received the most attention: cholinergic, dopaminergic, GABAergic, glutamatergic, serotonergic, noradrenergic, corticotrophin releasing hormone, opioid, and neuropeptide Y. Herein, we sought to place the P rat's behavioral and neurochemical phenotypes, and to some extent its genotype, in the context of the clinical literature. After reviewing the findings thus far, this chapter discusses future directions for expanding the use of this genetic animal model of alcoholism to identify molecular targets for treating drug addiction in general.
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Affiliation(s)
- R L Bell
- Institute of Psychiatric Research, Indiana University School of Medicine, Indianapolis, IN, United States.
| | - S Hauser
- Institute of Psychiatric Research, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Z A Rodd
- Institute of Psychiatric Research, Indiana University School of Medicine, Indianapolis, IN, United States
| | - T Liang
- Indiana University School of Medicine, Indianapolis, IN, United States
| | - Y Sari
- University of Toledo, Toledo, OH, United States
| | - J McClintick
- Center for Medical Genomics, Indiana University School of Medicine, Indianapolis, IN, United States
| | - S Rahman
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD, United States
| | - E A Engleman
- Institute of Psychiatric Research, Indiana University School of Medicine, Indianapolis, IN, United States
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38
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Engel JA, Nylander I, Jerlhag E. A ghrelin receptor (GHS-R1A) antagonist attenuates the rewarding properties of morphine and increases opioid peptide levels in reward areas in mice. Eur Neuropsychopharmacol 2015; 25:2364-71. [PMID: 26508707 DOI: 10.1016/j.euroneuro.2015.10.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 09/17/2015] [Accepted: 10/05/2015] [Indexed: 11/28/2022]
Abstract
Gut-brain hormones such as ghrelin have recently been suggested to have a role in reward regulation. Ghrelin was traditionally known to regulate food intake and body weight homoeostasis. In addition, recent work has pin-pointed that this peptide has a novel role in drug-induced reward, including morphine-induced increase in the extracellular levels of accumbal dopamine in rats. Herein the effect of the ghrelin receptor (GHS-R1A) antagonist, JMV2959, on morphine-induced activation of the mesolimbic dopamine system was investigated in mice. In addition, the effects of JMV2959 administration on opioid peptide levels in reward related areas were investigated. In the present series of experiment we showed that peripheral JMV2959 administration, at a dose with no effect per se, attenuates the ability of morphine to cause locomotor stimulation, increase the extracellular levels of accumbal dopamine and to condition a place preference in mice. JMV2959 administration significantly increased tissue levels of Met-enkephalin-Arg(6)Phe(7) in the ventral tegmental area, dynorphin B in hippocampus and Leu-enkephalin-Arg(6) in striatum. We therefore hypothesise that JMV2959 prevents morphine-induced reward via stimulation of delta receptor active peptides in striatum and ventral tegmental areas. In addition, hippocampal peptides that activate kappa receptor may be involved in JMV2959׳s ability to regulate memory formation of reward. Given that development of drug addiction depends, at least in part, of the effects of addictive drugs on the mesolimbic dopamine system the present data suggest that GHS-R1A antagonists deserve to be elucidated as novel treatment strategies of opioid addiction.
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Affiliation(s)
- Jörgen A Engel
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Ingrid Nylander
- Neuropharmacology, Addiction and Behaviour, Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, 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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Suchankova P, Engel JA, Jerlhag E. Sub-chronic Ghrelin Receptor Blockade Attenuates Alcohol- and Amphetamine-Induced Locomotor Stimulation in Mice. Alcohol Alcohol 2015; 51:121-7. [DOI: 10.1093/alcalc/agv100] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 07/16/2015] [Indexed: 11/14/2022] Open
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Liu S, Borgland S. Regulation of the mesolimbic dopamine circuit by feeding peptides. Neuroscience 2015; 289:19-42. [DOI: 10.1016/j.neuroscience.2014.12.046] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 12/27/2014] [Accepted: 12/31/2014] [Indexed: 12/30/2022]
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Hauberg K, Kohlmeier KA. The appetite-inducing peptide, ghrelin, induces intracellular store-mediated rises in calcium in addiction and arousal-related laterodorsal tegmental neurons in mouse brain slices. Peptides 2015; 65:34-45. [PMID: 25645492 DOI: 10.1016/j.peptides.2015.01.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 01/21/2015] [Accepted: 01/21/2015] [Indexed: 12/16/2022]
Abstract
Ghrelin, a gut and brain peptide, has recently been shown to be involved in motivated behavior and regulation of the sleep and wakefulness cycle. The laterodorsal tegmental nucleus (LDT) is involved in appetitive behavior and control of the arousal state of an organism, and accordingly, behavioral actions of ghrelin could be mediated by direct cellular actions within this nucleus. Consistent with this interpretation, postsynaptically mediated depolarizing membrane actions of ghrelin on LDT neurons have been reported. Direct actions were ascribed solely to closure of a potassium conductance however this peptide has been shown in other cell types to lead to rises in calcium via release of calcium from intracellular stores. To determine whether ghrelin induced intracellular calcium rises in mouse LDT neurons, we conducted calcium imaging studies in LDT brain slices loaded with the calcium binding dye, Fura-2AM. Ghrelin elicited TTX-insensitive changes in dF/F indicative of rises in calcium, and a portion of these rises were independent of membrane depolarization, as they persisted in conditions of high extracellular potassium solutions and were found to involve SERCA-pump mediated intracellular calcium stores. Involvement of the ghrelin receptor (GHR-S) in these actions was confirmed. Taken together with other studies, our data suggest that ghrelin has multiple cellular actions on LDT cells. Ghrelin's induction of calcium via intracellular release in the LDT could play a role in behavioral actions of this peptide as the LDT governs processes involved in stimulation of motivated behavior and control of cortical arousal.
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Affiliation(s)
- Katrine Hauberg
- Department of Drug Design and Pharmacology, Faculty of Health Sciences, Universitetsparken 2, University of Copenhagen, Copenhagen 2100, Denmark
| | - Kristi A Kohlmeier
- Department of Drug Design and Pharmacology, Faculty of Health Sciences, Universitetsparken 2, University of Copenhagen, Copenhagen 2100, Denmark.
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Wittekind DA, Kluge M. Ghrelin in psychiatric disorders - A review. Psychoneuroendocrinology 2015; 52:176-94. [PMID: 25459900 DOI: 10.1016/j.psyneuen.2014.11.013] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 11/13/2014] [Accepted: 11/13/2014] [Indexed: 12/21/2022]
Abstract
Ghrelin is a 28-amino-acid peptide hormone, first described in 1999 and broadly expressed in the organism. As the only known orexigenic hormone secreted in the periphery, it increases hunger and appetite, promoting food intake. Ghrelin has also been shown to be involved in various physiological processes being regulated in the central nervous system such as sleep, mood, memory and reward. Accordingly, it has been implicated in a series of psychiatric disorders, making it subject of increasing investigation, with knowledge rapidly accumulating. This review aims at providing a concise yet comprehensive overview of the role of ghrelin in psychiatric disorders. Ghrelin was consistently shown to exert neuroprotective and memory-enhancing effects and alleviated psychopathology in animal models of dementia. Few human studies show a disruption of the ghrelin system in dementia. It was also shown to play a crucial role in the pathophysiology of addictive disorders, promoting drug reward, enhancing drug seeking behavior and increasing craving in both animals and humans. Ghrelin's exact role in depression and anxiety is still being debated, as it was shown to both promote and alleviate depressive and anxiety-behavior in animal studies, with an overweight of evidence suggesting antidepressant effects. Not surprisingly, the ghrelin system is also implicated in eating disorders, however its exact role remains to be elucidated. Its widespread involvement has made the ghrelin system a promising target for future therapies, with encouraging findings in recent literature.
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Affiliation(s)
| | - Michael Kluge
- Department of Psychiatry and Psychotherapy, University of Leipzig, Leipzig, Germany
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Blockade of growth hormone secretagogue receptor 1A signaling by JMV 2959 attenuates the NMDAR antagonist, phencyclidine-induced impairments in prepulse inhibition. Psychopharmacology (Berl) 2015; 232:4285-92. [PMID: 26319159 PMCID: PMC4613889 DOI: 10.1007/s00213-015-4054-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 08/17/2015] [Indexed: 11/03/2022]
Abstract
RATIONALE Schizophrenic-spectrum patients commonly display deficits in preattentive information processing as evidenced, for example, by disrupted prepulse inhibition (PPI), a measure of sensorimotor gating. Similar disruptions in PPI can be induced in rodents and primates by the psychotomimetic drug phencyclidine (PCP), a noncompetitive inhibitor of the NMDA receptor. Mounting evidence suggests that the hunger hormone ghrelin and its constitutively active receptor influences neuronal circuits involved in the regulation of mood and cognition. OBJECTIVES In the present series of experiments, we investigated the effects of ghrelin and the growth hormone secretagogue receptor (GHS-R1A) neutral antagonist, JMV 2959, on acoustic startle responses (ASR), PPI, and PCP-induced alterations in PPI. RESULTS Intraperitoneal (i.p.) administration of ghrelin (0.033, 0.1, and 0.33 mg/kg) did not alter the ASR or PPI in rats. Conversely, i.p. injection of JMV 2959 (1, 3, and 6 mg/kg), dose dependently decreased the ASR and increased PPI. Pretreatment with JMV 2959 at a dose with no effect on ASR or PPI per se, completely blocked PCP-induced (2 mg/kg) deficits in PPI while pretreatment with the highest dose of ghrelin did not potentiate or alter PPI responses of a sub-threshold dose of PCP (0.75 mg/kg). CONCLUSION These findings indicate that the GHS-R1A is involved in specific behavioral effects of PCP and may have relevance for patients with schizophrenia.
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Dietary sugars: their detection by the gut-brain axis and their peripheral and central effects in health and diseases. Eur J Nutr 2014; 54:1-24. [PMID: 25296886 PMCID: PMC4303703 DOI: 10.1007/s00394-014-0776-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 09/24/2014] [Indexed: 12/25/2022]
Abstract
Background Substantial increases in dietary sugar intake together with the increasing prevalence of obesity worldwide, as well as the parallels found between sugar overconsumption and drug abuse, have motivated research on the adverse effects of sugars on health and eating behaviour. Given that the gut–brain axis depends on multiple interactions between peripheral and central signals, and because these signals are interdependent, it is crucial to have a holistic view about dietary sugar effects on health. Methods Recent data on the effects of dietary sugars (i.e. sucrose, glucose, and fructose) at both peripheral and central levels and their interactions will be critically discussed in order to improve our understanding of the effects of sugars on health and diseases. This will contribute to the development of more efficient strategies for the prevention and treatment for obesity and associated co-morbidities. Results This review highlights opposing effects of glucose and fructose on metabolism and eating behaviour. Peripheral glucose and fructose sensing may influence eating behaviour by sweet-tasting mechanisms in the mouth and gut, and by glucose-sensing mechanisms in the gut. Glucose may impact brain reward regions and eating behaviour directly by crossing the blood–brain barrier, and indirectly by peripheral neural input and by oral and intestinal sweet taste/sugar-sensing mechanisms, whereas those promoted by fructose orally ingested seem to rely only on these indirect mechanisms. Conclusions Given the discrepancies between studies regarding the metabolic effects of sugars, more studies using physiological experimental conditions and in animal models closer to humans are needed. Additional studies directly comparing the effects of sucrose, glucose, and fructose should be performed to elucidate possible differences between these sugars on the reward circuitry.
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Vadnie CA, Park JH, Abdel Gawad N, Ho AMC, Hinton DJ, Choi DS. Gut-brain peptides in corticostriatal-limbic circuitry and alcohol use disorders. Front Neurosci 2014; 8:288. [PMID: 25278825 PMCID: PMC4166902 DOI: 10.3389/fnins.2014.00288] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 08/26/2014] [Indexed: 12/22/2022] Open
Abstract
Peptides synthesized in endocrine cells in the gastrointestinal tract and neurons are traditionally considered regulators of metabolism, energy intake, and appetite. However, recent work has demonstrated that many of these peptides act on corticostriatal-limbic circuitry and, in turn, regulate addictive behaviors. Given that alcohol is a source of energy and an addictive substance, it is not surprising that increasing evidence supports a role for gut-brain peptides specifically in alcohol use disorders (AUD). In this review, we discuss the effects of several gut-brain peptides on alcohol-related behaviors and the potential mechanisms by which these gut-brain peptides may interfere with alcohol-induced changes in corticostriatal-limbic circuitry. This review provides a summary of current knowledge on gut-brain peptides focusing on five peptides: neurotensin, glucagon-like peptide 1, ghrelin, substance P, and neuropeptide Y. Our review will be helpful to develop novel therapeutic targets for AUD.
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Affiliation(s)
- Chelsea A Vadnie
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine Rochester, MN, USA ; Neurobiology of Disease Program, Mayo Clinic College of Medicine Rochester, MN, USA
| | - Jun Hyun Park
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine Rochester, MN, USA ; Department of Psychiatry, Sanggye Paik Hospital, College of Medicine, InJe University Seoul, South Korea
| | - Noha Abdel Gawad
- Department of Psychiatry and Psychology, Mayo Clinic College of Medicine Rochester, MN, USA
| | - Ada Man Choi Ho
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine Rochester, MN, USA ; Department of Psychiatry and Psychology, Mayo Clinic College of Medicine Rochester, MN, USA
| | - David J Hinton
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine Rochester, MN, USA ; Neurobiology of Disease Program, Mayo Clinic College of Medicine Rochester, MN, USA
| | - Doo-Sup Choi
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine Rochester, MN, USA ; Neurobiology of Disease Program, Mayo Clinic College of Medicine Rochester, MN, USA ; Department of Psychiatry and Psychology, Mayo Clinic College of Medicine Rochester, MN, USA
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van de Giessen E, Celik F, Schweitzer DH, van den Brink W, Booij J. Dopamine D2/3 receptor availability and amphetamine-induced dopamine release in obesity. J Psychopharmacol 2014; 28:866-73. [PMID: 24785761 DOI: 10.1177/0269881114531664] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
INTRODUCTION The neurotransmitter dopamine is important in the regulation of food intake. It is hypothesised that obese people experience less reward from food due to lower striatal dopamine release, which consequently leads to overeating. This study is the first to assess whether obese subjects have blunted striatal dopamine release. METHOD We measured striatal dopamine D2/3 receptor (DRD2/3) availability and amphetamine-induced striatal dopamine release in 15 obese and 15 age-matched, normal-weight women using [(123)I]iodobenzamide single photon emission computed tomography (SPECT) imaging. In addition, correlations with food craving were examined. RESULTS Baseline striatal DRD2/3 availability was lower in obese subjects (0.91 ± 0.16) compared to controls (1.09 ± 0.16; p = 0.006). Amphetamine-induced dopamine release was significant in controls (7.5% ± 9.2; p = 0.007) and not in obese subjects (1.2% ± 17.7; p = 0.802), although the difference in release between groups (d=0.45) was not significant. Dopamine release positively correlated with the trait food craving in obese subjects. CONCLUSION This study replicates previous findings of lower striatal DRD2/3 availability in obesity and provides preliminary data that obesity is associated with blunted dopamine release. The positive correlation between dopamine release and food craving in obesity may seem contradictory with the latter finding but is presumably related to heterogeneity within the obese subjects.
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Affiliation(s)
- Elsmarieke van de Giessen
- Department of Nuclear Medicine, Academic Medical Center - University of Amsterdam, Amsterdam, The Netherlands
| | - Funda Celik
- Department of Internal Medicine, Slotervaart Hospital, Amsterdam, The Netherlands
| | - Dave H Schweitzer
- Department of Internal Medicine, Reinier de Graaf Group of Hospitals, Delft, The Netherlands
| | - Wim van den Brink
- Amsterdam Institute for Addiction Research, Academic Medical Center - University of Amsterdam, Amsterdam, The Netherlands
| | - Jan Booij
- Department of Nuclear Medicine, Academic Medical Center - University of Amsterdam, Amsterdam, The Netherlands
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Ghrelin receptor antagonism of morphine-induced accumbens dopamine release and behavioral stimulation in rats. Psychopharmacology (Berl) 2014; 231:2899-908. [PMID: 24531567 DOI: 10.1007/s00213-014-3466-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 01/15/2014] [Indexed: 12/24/2022]
Abstract
RATIONALE AND OBJECTIVES Ghrelin, an orexigenic (appetite stimulating) peptide activates binding sites in the ventral tegmental area (a structure linked with the neural reward system) allowing it to participate in reward-seeking behavior. An increasing number of studies over the past few years have demonstrated ghrelin's role in alcohol, cocaine, and nicotine abuse. However, the role of ghrelin, in opioid effects, has rarely been examined. The aim of the present study was to ascertain whether a ghrelin antagonist (JMV2959) was able to inhibit markers of morphine-induced activation of the neural reward system, namely morphine-induced increase of dopamine in the nucleus accumbens and behavioral changes in rats. METHODS We used in vivo microdialysis to determine changes of dopamine and its metabolites in the nucleus accumbens shell in rats following morphine (MO, 5, 10 mg/kg s.c.) administration with and without ghrelin antagonist pretreatment (JMV2959, 3, 6 mg/kg i.p., 20 min before MO). Induced behavioral changes were simultaneously monitored. RESULTS JMV2959 significantly and dose dependently reduced MO-induced dopamine release in the nucleus accumbens shell and affected concentration of by-products associated with dopamine metabolism: 3-methoxytyramine (3-MT), 3,4-dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA). JMV2959 pretreatment also significantly reduced MO-induced behavioral stimulation, especially stereotyped behavior. CONCLUSIONS Ghrelin secretagogue receptors (GHS-R1A) appear to be involved in the opioid-induced changes in the mesolimbic dopaminergic system associated with the reward processing.
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Quarta D, Smolders I. Rewarding, reinforcing and incentive salient events involve orexigenic hypothalamic neuropeptides regulating mesolimbic dopaminergic neurotransmission. Eur J Pharm Sci 2014; 57:2-10. [DOI: 10.1016/j.ejps.2014.01.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 01/19/2014] [Indexed: 12/22/2022]
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Engel JA, Jerlhag E. Role of appetite-regulating peptides in the pathophysiology of addiction: implications for pharmacotherapy. CNS Drugs 2014; 28:875-86. [PMID: 24958205 PMCID: PMC4181507 DOI: 10.1007/s40263-014-0178-y] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Food intake and appetite are regulated by various circulating hormones including ghrelin and glucagon-like-peptide 1 (GLP-1). Ghrelin, mainly released from the stomach, increases food intake, induces appetite, enhances adiposity as well as releases growth hormone. Hypothalamic "ghrelin receptors" (GHS-R1A) have a critical role in food intake regulation, but GHS-R1A are also expressed in reward related areas. GLP-1 is produced in the intestinal mucosa as well as in the hindbrain in response to nutrient ingestion. This gut-brain hormone reduces food intake as well as regulates glucose homeostasis, foremost via GLP-1 receptors in hypothalamus and brain stem. However, GLP-1 receptors are expressed in areas intimately associated with reward regulation. Given that regulation of food and drug intake share common neurobiological substrates, the possibility that ghrelin and GLP-1 play an important role in reward regulation should be considered. Indeed, this leading article describes that the orexigenic peptide ghrelin activates the cholinergic-dopaminergic reward link, an important part of the reward systems in the brain associated with reinforcement and thereby increases the incentive salience for motivated behaviors via this system. We also review the role of ghrelin signaling for reward induced by alcohol and addictive drugs from a preclinical, clinical and human genetic perspective. In addition, the recent findings showing that GLP-1 controls reward induced by alcohol, amphetamine, cocaine and nicotine in rodents are overviewed herein. Finally, the role of several other appetite regulatory hormones for reward and addiction is briefly discussed. Collectively, these data suggest that ghrelin and GLP-1 receptors may be novel targets for development of pharmacological treatments of alcohol and drug dependence.
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Affiliation(s)
- Jörgen A. Engel
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, POB 431, 405 30 Gothenburg, Sweden
| | - Elisabet Jerlhag
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, POB 431, 405 30 Gothenburg, Sweden
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