1
|
Ballaz S, Espinosa N, Bourin M. Does endogenous cholecystokinin modulate alcohol intake? Neuropharmacology 2021; 193:108539. [PMID: 33794246 DOI: 10.1016/j.neuropharm.2021.108539] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 02/06/2021] [Accepted: 03/22/2021] [Indexed: 02/08/2023]
Abstract
Alcohol use disorder or alcoholism is characterized by uncontrollable alcohol use and intoxication, as well as a heightened state of anxiety after alcohol withdrawal. Ethanol-associated stimuli also drive the urge to drink by means of classical conditioning. Alcoholism has been considered a dopamine (DA) dysregulation syndrome that involves the activity of the central amygdala circuitry of anxiety. Cholecystokinin (CCK) is the most abundant neuropeptide in the mammal brain, where it activates two receptors, CCK1 and CCK2. Genetic evidence relates CCK1 receptors to alcoholism in humans. CCK2 activity has been associated with the onset of human anxiety. CCK modulates DA release in the nucleus accumbens (NAc) and it is expressed in the γ-aminobutyric acid (GABA)-expressing basket interneurons in the cerebral cortex. CCK interacts with serotonin (5-HT) neurotransmission through 5-HT3 receptors to regulate mesocorticolimbic pathways and with GABA to attenuate anxiety in the amygdala. Finally, CCK stimulates the release of orexins and oxytocin in the hypothalamus, two relevant hypothalamic neuropeptides involved in signaling satiety for ethanol and well-being respectively. Given the "dimmer-switch" function of endogenous CCK in the neurotransmission by 5-HT, DA, GABA, and glutamate in normal and pathological behaviors (Ballaz and Bourin, 2020), we hypothesize that CCK adjusts functioning of the reward and anxiety circuitries altered by ethanol. This review gathers data supporting this hypothesis, and suggests mechanisms underlying a role for endogenous CCK in alcoholism.
Collapse
Affiliation(s)
- Santiago Ballaz
- School of Biological Sciences & Engineering, Yachay Tech University, Hacienda San José s/n, San Miguel de Urcuquí, Ecuador; School of Medicine, Universidad Espíritu Santo, Samborondón, Ecuador.
| | - Nicole Espinosa
- School of Biological Sciences & Engineering, Yachay Tech University, Hacienda San José s/n, San Miguel de Urcuquí, Ecuador.
| | - Michel Bourin
- Neurobiology of Anxiety and Mood Disorders, University of Nantes, 98, Rue Joseph Blanchart, 44100 Nantes, France.
| |
Collapse
|
2
|
Kunos G. Interactions Between Alcohol and the Endocannabinoid System. Alcohol Clin Exp Res 2020; 44:790-805. [PMID: 32056226 DOI: 10.1111/acer.14306] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 02/05/2020] [Indexed: 12/12/2022]
Abstract
Endocannabinoids are lipid mediators that interact with the same cannabinoid receptors that recognize Δ9 -tetrahydrocannabinol (THC), the psychoactive constituent of marijuana, to induce similar effects in the brain and periphery. Alcohol and THC are both addictive substances whose acute use elicits rewarding effects that can lead to chronic and compulsive use via engaging similar signaling pathways in the brain. In the liver, both alcohol and endocannabinoids activate lipogenic gene expression leading to fatty liver disease. This review focuses on evidence accumulated over the last 2 decades to indicate that both the addictive neural effects of ethanol and its organ toxic effects in the liver and elsewhere are mediated, to a large extent, by endocannabinoids signaling via cannabinoid-1 receptors (CB1 R). The therapeutic potential of CB1 R blockade globally or in peripheral tissues only is also discussed.
Collapse
Affiliation(s)
- George Kunos
- From the, Division of Clinical and Biological Research, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland
| |
Collapse
|
3
|
Godlewski G, Cinar R, Coffey NJ, Liu J, Jourdan T, Mukhopadhyay B, Chedester L, Liu Z, Osei-Hyiaman D, Iyer MR, Park JK, Smith RG, Iwakura H, Kunos G. Targeting Peripheral CB 1 Receptors Reduces Ethanol Intake via a Gut-Brain Axis. Cell Metab 2019; 29:1320-1333.e8. [PMID: 31105045 PMCID: PMC6551287 DOI: 10.1016/j.cmet.2019.04.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 03/01/2019] [Accepted: 04/21/2019] [Indexed: 12/21/2022]
Abstract
Endocannabinoids acting on the cannabinoid-1 receptor (CB1R) or ghrelin acting on its receptor (GHS-R1A) both promote alcohol-seeking behavior, but an interaction between the two signaling systems has not been explored. Here, we report that the peripheral CB1R inverse agonist JD5037 reduces ethanol drinking in wild-type mice but not in mice lacking CB1R, ghrelin peptide or GHS-R1A. JD5037 treatment of alcohol-drinking mice inhibits the formation of biologically active octanoyl-ghrelin without affecting its inactive precursor desacyl-ghrelin. In ghrelin-producing stomach cells, JD5037 reduced the level of the substrate octanoyl-carnitine generated from palmitoyl-carnitine by increasing fatty acid β-oxidation. Blocking gastric vagal afferents abrogated the ability of either CB1R or GHS-R1A blockade to reduce ethanol drinking. We conclude that blocking CB1R in ghrelin-producing cells reduces alcohol drinking by inhibiting the formation of active ghrelin and its signaling via gastric vagal afferents. Thus, peripheral CB1R blockade may have therapeutic potential in the treatment of alcoholism.
Collapse
Affiliation(s)
- Grzegorz Godlewski
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Resat Cinar
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Nathan J Coffey
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jie Liu
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tony Jourdan
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Bani Mukhopadhyay
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lee Chedester
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ziyi Liu
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Douglas Osei-Hyiaman
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Malliga R Iyer
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Joshua K Park
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Roy G Smith
- Scripps Research Institute, Jupiter, FL 33458, USA
| | - Hiroshi Iwakura
- Wakayama Medical University, 811-1 Kimiidera, Wakayama 641-8509, Japan
| | - George Kunos
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA.
| |
Collapse
|
4
|
Abramov U, Raud S, Innos J, Kõks S, Matsui T, Vasar E. Gender specific effects of ethanol in mice, lacking CCK2 receptors. Behav Brain Res 2006; 175:149-56. [PMID: 16970998 DOI: 10.1016/j.bbr.2006.08.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Revised: 08/11/2006] [Accepted: 08/15/2006] [Indexed: 10/24/2022]
Abstract
Neuropeptide cholecystokinin (CCK) has been reported to suppress ethanol intake, but there is contradictory evidence about the role of CCK(2) receptors. In the present study anxiolytic, hypolocomotor and sedative effects of acute ethanol administration, but also voluntary ethanol consumption were studied in male and female mice, lacking CCK(2) receptors (-/-). Ethanol (1.0 and 2.0 g/kg) induced a significant reduction of anxiety-related behaviours in the elevated plus-maze, but this effect was statistically significant only in female homozygous mice (-/-). In male mice, lacking CCK(2) receptors (-/-), but not in their wild-type littermates (+/+), the suppression of vertical locomotor activity was caused by ethanol at a dose 0.5 g/kg. The highest dose of ethanol (2.0 g/kg) produced statistically significant reduction of horizontal locomotor activity only in female wild-type (+/+) mice, but this effect was related to increased basal activity when compared to female mutant (-/-) mice. Duration of the loss of righting reflex was not significantly affected by genotype or gender, but blood ethanol levels at regain of righting reflex were significantly lower in female homozygous mice (-/-) compared to their wild-type (+/+) littermates, indicating increased sensitivity to the sedative effect of ethanol. Ethanol intake, but not preference, at concentration 10% was significantly increased in female mice, lacking CCK(2) receptors (-/-). The present study revealed an altered response to the acute effects of ethanol in CCK(2) receptor deficient mice (-/-). These changes are gender-specific and could be attributed to the altered activity of dopaminergic system in male mice and increased activity of GABA-ergic system in female mice as established in our previous studies.
Collapse
Affiliation(s)
- Urho Abramov
- Department of Physiology, University of Tartu, 19 Ravila Street, 50411 Tartu, Estonia.
| | | | | | | | | | | |
Collapse
|
5
|
Lawrence AJ, Cowen MS, Yang HJ, Chen F, Oldfield B. The orexin system regulates alcohol-seeking in rats. Br J Pharmacol 2006; 148:752-9. [PMID: 16751790 PMCID: PMC1617074 DOI: 10.1038/sj.bjp.0706789] [Citation(s) in RCA: 313] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. Orexin-containing neurons have been implicated in feeding, sleep-wake cycles and more recently in drug-seeking behaviour. 2. Pretreatment of alcohol-preferring (iP) rats with an orexin1 receptor antagonist (SB-334867, 20 mg kg(-1), intraperitoneally) completely abolished an olfactory cue-induced reinstatement of alcohol-seeking behaviour, and also attenuated alcohol responding under an operant fixed ratio regimen without affecting water responding. 3. The mRNA encoding orexin within the hypothalamus was expressed at a similar density in iP and non-preferring (NP) rats; chronic consumption of ethanol in iP rats did not significantly regulate the density of this expression, but did increase the area of expression within the lateral, but not medial, hypothalamus. 4. These data indicate that while orexin may not be implicated in the development of an alcohol preference, re-exposure of cues previously associated with alcohol availability is sufficient and adequate to activate orexin-containing neurons and drive reinstatement of alcohol-seeking.
Collapse
Affiliation(s)
- Andrew J Lawrence
- Brain Injury & Repair Group, Howard Florey Institute, University of Melbourne, Royal Parade, Parkville, Victoria 3010, Australia.
| | | | | | | | | |
Collapse
|