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Giannone F, Ebrahimi C, Endrass T, Hansson AC, Schlagenhauf F, Sommer WH. Bad habits-good goals? Meta-analysis and translation of the habit construct to alcoholism. Transl Psychiatry 2024; 14:298. [PMID: 39030169 PMCID: PMC11271507 DOI: 10.1038/s41398-024-02965-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 05/19/2024] [Accepted: 05/24/2024] [Indexed: 07/21/2024] Open
Abstract
Excessive alcohol consumption remains a global public health crisis, with millions suffering from alcohol use disorder (AUD, or simply "alcoholism"), leading to significantly reduced life expectancy. This review examines the interplay between habitual and goal-directed behaviors and the associated neurobiological changes induced by chronic alcohol exposure. Contrary to a strict habit-goal dichotomy, our meta-analysis of the published animal experiments combined with a review of human studies reveals a nuanced transition between these behavioral control systems, emphasizing the need for refined terminology to capture the probabilistic nature of decision biases in individuals with a history of chronic alcohol exposure. Furthermore, we distinguish habitual responding from compulsivity, viewing them as separate entities with diverse roles throughout the stages of the addiction cycle. By addressing species-specific differences and translational challenges in habit research, we provide insights to enhance future investigations and inform strategies for combatting AUD.
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Affiliation(s)
- F Giannone
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, 68159, Mannheim, Germany
| | - C Ebrahimi
- Faculty of Psychology, Institute of Clinical Psychology and Psychotherapy, Technische Universität Dresden, 01062, Dresden, Germany
| | - T Endrass
- Faculty of Psychology, Institute of Clinical Psychology and Psychotherapy, Technische Universität Dresden, 01062, Dresden, Germany
| | - A C Hansson
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, 68159, Mannheim, Germany
| | - F Schlagenhauf
- Department of Psychotherapy, Campus Charité Mitte, Charité Universitätsmedizin Berlin & St. Hedwig Hospital, 10117, Berlin, Germany
| | - W H Sommer
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, 68159, Mannheim, Germany.
- Bethania Hospital for Psychiatry, Psychosomatics and Psychotherapy, Greifswald, Germany.
- German Center for Mental Health (DZPG), Partner Site Mannheim-Heidelberg-Ulm, 68159, Mannheim, Germany.
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2
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C.A. G, G.B. G, H.L. H, D. P, T. S, S.L. D, K. B, W.P. K, C.W. H, T.L. K. Disentangling the effects of Corticotrophin Releasing Factor and GABA release from the ventral bed nucleus of the stria terminalis on ethanol self-administration in mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.02.530838. [PMID: 37205547 PMCID: PMC10187230 DOI: 10.1101/2023.03.02.530838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Excessive alcohol use causes a great deal of harm and negative health outcomes. Corticotrophin releasing factor (CRF), a stress-related neuropeptide, has been implicated in binge ethanol intake and ethanol dependence. CRF containing neurons in the bed nucleus of the stria terminalis (BNSTCRF) can control ethanol consumption. These BNSTCRF neurons also release GABA, raising the question, is it CRF or GABA release or both that is controlling alcohol consumption. Here, we used viral vectors to separate the effects of CRF and GABA release from BNSTCRF neurons on the escalation of ethanol intake in an operant self-administration paradigm in male and female mice. We found that CRF deletion in BNST neurons reduces ethanol intake in both sexes, with a stronger effect in males. For sucrose self-administration there was no effect of CRF deletion. Suppression of GABA release, via knockdown of vGAT, from BNSTCRF produced a transient increase in ethanol operant self-administration following in male mice, and reduced in motivation to work for sucrose on a progressive ratio schedule of reinforcement in a sex-dependent manner. Together, these results highlight how different signaling molecules from the same populations of neurons can bidirectionally control behavior. Moreover, they suggest that BNST CRF release is important for high intensity ethanol drinking that precedes dependence, whereas GABA release from these neurons may play a role in regulating motivation.
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3
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Fischler PV, Soyka M, Seifritz E, Mutschler J. Off-label and investigational drugs in the treatment of alcohol use disorder: A critical review. Front Pharmacol 2022; 13:927703. [PMID: 36263121 PMCID: PMC9574013 DOI: 10.3389/fphar.2022.927703] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 06/30/2022] [Indexed: 11/13/2022] Open
Abstract
Compounds known to be successful in the treatment of alcohol use disorder include the aversive agent, Disulfiram, the glutamatergic NMDA receptor antagonist, Acamprosate, and the opioid receptor antagonists, Naltrexone and Nalmefene. Although all four are effective in maintaining abstinence or reduction of alcohol consumption, only a small percentage of patients receive pharmacological treatment. In addition, many other medications have been investigated for their therapeutic potential in the treatment of alcohol use disorder. In this review we summarize and compare Baclofen, Gabapentin, Topiramate, Ondansetron, Varenicline, Aripiprazole, Quetiapine, Clozapine, Antidepressants, Lithium, Neuropeptide Y, Neuropeptide S, Corticotropin-releasing factor antagonists, Oxytocin, PF-05190457, Memantine, Ifenprodil, Samidorphan, Ondelopran, ABT-436, SSR149415, Mifepristone, Ibudilast, Citicoline, Rimonabant, Surinabant, AM4113 and Gamma-hydroxybutyrate While some have shown promising results in the treatment of alcohol use disorder, others have disappointed and should be excluded from further investigation. Here we discuss the most promising results and highlight medications that deserve further preclinical or clinical study. Effective, patient-tailored treatment will require greater understanding provided by many more preclinical and clinical studies.
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Affiliation(s)
- Pascal Valentin Fischler
- Department for Gynecology and Obstetrics, Women’s Clinic Lucerne, Cantonal Hospital of Lucerne, Lucerne, Switzerland
- *Correspondence: Pascal Valentin Fischler,
| | - Michael Soyka
- Psychiatric Hospital University of Munich, Munich, Germany
| | - Erich Seifritz
- Director of the Clinic for Psychiatry, Psychotherapy and Psychosomatics, Psychiatric University Clinic Zürich, Zürich, Switzerland
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4
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Bornscheuer L, Lundin A, Forsell Y, Lavebratt C, Melas PA. The cannabinoid receptor-1 gene interacts with stressful life events to increase the risk for problematic alcohol use. Sci Rep 2022; 12:4963. [PMID: 35322131 PMCID: PMC8941304 DOI: 10.1038/s41598-022-08980-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 03/15/2022] [Indexed: 02/07/2023] Open
Abstract
Problematic alcohol use is a major contributor to the global burden of death and disabilities, and it represents a public health concern that has grown substantially following the COVID-19 pandemic. The available treatment options remain limited and to develop better pharmacotherapies for alcohol misuse we need to identify suitable biological targets. Previous research has implicated the brain’s endocannabinoid system (ECS) in psychiatric and stress-related outcomes, including substance use and habituation to repeated stress. Moreover, genetic variants in the cannabinoid-1 receptor gene (CNR1; CB1R) have been associated with personality traits, which are in turn predictors of substance use disorders. To date, however, no human genome-wide association study has provided evidence for an involvement of the ECS in substance use outcomes. One reason for this ECS-related “missing heritability” may be unexamined gene-environment interactions. To explore this possibility, we conducted cross-sectional analyses using DNA samples and stress-exposure data from a longitudinal Swedish population-based study (N = 2,915). Specifically, we genotyped rs2023239, a functional C/T single nucleotide polymorphism in CNR1, previously reported to be associated with CNR1 binding in the brain, subjective reward following alcohol intake, and alcohol cue-elicited brain activation. Our two outcomes of interest were (i) problematic alcohol use based on the Alcohol Use Disorders Identification Test (AUDIT), and (ii) personality trait scores based on the Five Factor Model. We found no baseline association between rs2023239 and problematic alcohol use or personality traits. However, there was a clear trend for interaction between rs2023239’s risk allele (C) and stressful life events (SLEs) in both childhood and adulthood, which predicted problematic alcohol use. Although not significant, there was also some indication that the risk allele interacted with child SLEs to increase scores on neuroticism. Our study supports the notion that the ECS can affect alcohol intake behaviors by interacting with life adversities and is—to the best of our knowledge—the first to focus on the interaction between CNR1 and stressors in both childhood and adulthood in humans. Further studies are warranted to confirm these findings.
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Affiliation(s)
- Lisa Bornscheuer
- Department of Public Health Sciences, Stockholm University, 10691, Stockholm, Sweden.,Center for Molecular Medicine, L8:00, Karolinska University Hospital, 17176, Stockholm, Sweden
| | - Andreas Lundin
- Department of Global Public Health, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Yvonne Forsell
- Department of Global Public Health, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Catharina Lavebratt
- Center for Molecular Medicine, L8:00, Karolinska University Hospital, 17176, Stockholm, Sweden.,Department of Molecular Medicine and Surgery, Karolinska Institutet, 17176, Stockholm, Sweden
| | - Philippe A Melas
- Center for Molecular Medicine, L8:00, Karolinska University Hospital, 17176, Stockholm, Sweden. .,Center for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet and Stockholm Health Care Services, 11364, Stockholm, Sweden.
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5
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On the Biomedical Properties of Endocannabinoid Degradation and Reuptake Inhibitors: Pre-clinical and Clinical Evidence. Neurotox Res 2021; 39:2072-2097. [PMID: 34741755 DOI: 10.1007/s12640-021-00424-z] [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: 07/19/2021] [Revised: 09/14/2021] [Accepted: 09/28/2021] [Indexed: 10/19/2022]
Abstract
The endocannabinoid system (ECS) is composed of endogenous cannabinoids; components involved in their synthesis, transport, and degradation; and an expansive variety of cannabinoid receptors. Hypofunction or deregulation of the ECS is related to pathological conditions. Consequently, endogenous enhancement of endocannabinoid levels and/or regulation of their metabolism represent promising therapeutic approaches. Several major strategies have been suggested for the modulation of the ECS: (1) blocking endocannabinoids degradation, (2) inhibition of endocannabinoid cellular uptake, and (3) pharmacological modulation of cannabinoid receptors as potential therapeutic targets. Here, we focused in this review on degradation/reuptake inhibitors over cannabinoid receptor modulators in order to provide an updated synopsis of contemporary evidence advancing mechanisms of endocannabinoids as pharmacological tools with therapeutic properties for the treatment of several disorders. For this purpose, we revisited the available literature and reported the latest advances regarding the biomedical properties of fatty acid amide hydrolase and monoacylglycerol lipase inhibitors in pre-clinical and clinical studies. We also highlighted anandamide and 2-arachidonoylglycerol reuptake inhibitors with promising results in pre-clinical studies using in vitro and animal models as an outlook for future research in clinical trials.
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6
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Winters ND, Bedse G, Astafyev AA, Patrick TA, Altemus M, Morgan AJ, Mukerjee S, Johnson KD, Mahajan VR, Uddin MJ, Kingsley PJ, Centanni SW, Siciliano CA, Samuels DC, Marnett LJ, Winder DG, Patel S. Targeting diacylglycerol lipase reduces alcohol consumption in preclinical models. J Clin Invest 2021; 131:146861. [PMID: 34292886 PMCID: PMC8409586 DOI: 10.1172/jci146861] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 07/20/2021] [Indexed: 12/13/2022] Open
Abstract
Alcohol use disorder (AUD) is associated with substantial morbidity, mortality, and societal cost, and pharmacological treatment options for AUD are limited. The endogenous cannabinoid (eCB) signaling system is critically involved in reward processing and alcohol intake is positively correlated with release of the eCB ligand 2-Arachidonoylglycerol (2-AG) within reward neurocircuitry. Here we show that genetic and pharmacological inhibition of diacylglycerol lipase (DAGL), the rate limiting enzyme in the synthesis of 2-AG, reduces alcohol consumption in a variety of preclinical models ranging from a voluntary free-access model to aversion resistant-drinking and dependence-like drinking induced via chronic intermittent ethanol vapor exposure in mice. DAGL inhibition during either chronic alcohol consumption or protracted withdrawal was devoid of anxiogenic and depressive-like behavioral effects. Lastly, DAGL inhibition also prevented ethanol-induced suppression of GABAergic transmission onto midbrain dopamine neurons, providing mechanistic insight into how DAGL inhibition could affect alcohol reward. These data suggest reducing 2-AG signaling via inhibition of DAGL could represent an effective approach to reduce alcohol consumption across the spectrum of AUD severity.
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Affiliation(s)
- Nathan D. Winters
- Department of Psychiatry and Behavioral Sciences
- Vanderbilt Center for Addiction Research
- Department of Pharmacology
| | - Gaurav Bedse
- Department of Psychiatry and Behavioral Sciences
- Vanderbilt Center for Addiction Research
| | | | | | | | | | - Snigdha Mukerjee
- Vanderbilt Center for Addiction Research
- Department of Pharmacology
| | | | | | - Md Jashim Uddin
- Departments of Biochemistry and Chemistry, A.B. Hancock Jr. Memorial Laboratory for Cancer Research, Vanderbilt Institute of Chemical Biology
| | - Philip J. Kingsley
- Departments of Biochemistry and Chemistry, A.B. Hancock Jr. Memorial Laboratory for Cancer Research, Vanderbilt Institute of Chemical Biology
| | - Samuel W. Centanni
- Vanderbilt Center for Addiction Research
- Department of Molecular Physiology and Biophysics
- Vanderbilt Brain Institute, and
| | - Cody A. Siciliano
- Vanderbilt Center for Addiction Research
- Department of Pharmacology
- Vanderbilt Brain Institute, and
| | - David C. Samuels
- Department of Molecular Physiology and Biophysics
- Vanderbilt Genetics Institute, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Lawrence J. Marnett
- Department of Pharmacology
- Departments of Biochemistry and Chemistry, A.B. Hancock Jr. Memorial Laboratory for Cancer Research, Vanderbilt Institute of Chemical Biology
| | - Danny G. Winder
- Vanderbilt Center for Addiction Research
- Department of Molecular Physiology and Biophysics
- Vanderbilt Brain Institute, and
| | - Sachin Patel
- Department of Psychiatry and Behavioral Sciences
- Vanderbilt Center for Addiction Research
- Department of Pharmacology
- Department of Molecular Physiology and Biophysics
- Vanderbilt Brain Institute, and
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7
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Oleson EB, Hamilton LR, Gomez DM. Cannabinoid Modulation of Dopamine Release During Motivation, Periodic Reinforcement, Exploratory Behavior, Habit Formation, and Attention. Front Synaptic Neurosci 2021; 13:660218. [PMID: 34177546 PMCID: PMC8222827 DOI: 10.3389/fnsyn.2021.660218] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 05/05/2021] [Indexed: 12/12/2022] Open
Abstract
Motivational and attentional processes energize action sequences to facilitate evolutionary competition and promote behavioral fitness. Decades of neuropharmacology, electrophysiology and electrochemistry research indicate that the mesocorticolimbic DA pathway modulates both motivation and attention. More recently, it was realized that mesocorticolimbic DA function is tightly regulated by the brain's endocannabinoid system and greatly influenced by exogenous cannabinoids-which have been harnessed by humanity for medicinal, ritualistic, and recreational uses for 12,000 years. Exogenous cannabinoids, like the primary psychoactive component of cannabis, delta-9-tetrahydrocannabinol, produce their effects by acting at binding sites for naturally occurring endocannabinoids. The brain's endocannabinoid system consists of two G-protein coupled receptors, endogenous lipid ligands for these receptor targets, and several synthetic and metabolic enzymes involved in their production and degradation. Emerging evidence indicates that the endocannabinoid 2-arachidonoylglycerol is necessary to observe concurrent increases in DA release and motivated behavior. And the historical pharmacology literature indicates a role for cannabinoid signaling in both motivational and attentional processes. While both types of behaviors have been scrutinized under manipulation by either DA or cannabinoid agents, there is considerably less insight into prospective interactions between these two important signaling systems. This review attempts to summate the relevance of cannabinoid modulation of DA release during operant tasks designed to investigate either motivational or attentional control of behavior. We first describe how cannabinoids influence DA release and goal-directed action under a variety of reinforcement contingencies. Then we consider the role that endocannabinoids might play in switching an animal's motivation from a goal-directed action to the search for an alternative outcome, in addition to the formation of long-term habits. Finally, dissociable features of attentional behavior using both the 5-choice serial reaction time task and the attentional set-shifting task are discussed along with their distinct influences by DA and cannabinoids. We end with discussing potential targets for further research regarding DA-cannabinoid interactions within key substrates involved in motivation and attention.
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Affiliation(s)
- Erik B. Oleson
- Department of Psychology, University of Colorado Denver, Denver, CO, United States
| | - Lindsey R. Hamilton
- Department of Psychology, University of Colorado Denver, Denver, CO, United States
| | - Devan M. Gomez
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI, United States
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8
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Renteria R, Cazares C, Baltz ET, Schreiner DC, Yalcinbas EA, Steinkellner T, Hnasko TS, Gremel CM. Mechanism for differential recruitment of orbitostriatal transmission during actions and outcomes following chronic alcohol exposure. eLife 2021; 10:67065. [PMID: 33729155 PMCID: PMC8016477 DOI: 10.7554/elife.67065] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 03/16/2021] [Indexed: 12/26/2022] Open
Abstract
Psychiatric disease often produces symptoms that have divergent effects on neural activity. For example, in drug dependence, dysfunctional value-based decision-making and compulsive-like actions have been linked to hypo- and hyperactivity of orbital frontal cortex (OFC)-basal ganglia circuits, respectively; however, the underlying mechanisms are unknown. Here we show that alcohol-exposed mice have enhanced activity in OFC terminals in dorsal striatum (OFC-DS) associated with actions, but reduced activity of the same terminals during periods of outcome retrieval, corresponding with a loss of outcome control over decision-making. Disrupted OFC-DS terminal activity was due to a dysfunction of dopamine-type 1 receptors on spiny projection neurons (D1R SPNs) that resulted in increased retrograde endocannabinoid signaling at OFC-D1R SPN synapses reducing OFC-DS transmission. Blocking CB1 receptors restored OFC-DS activity in vivo and rescued outcome-based control over decision-making. These findings demonstrate a circuit-, synapse-, and computation-specific mechanism gating OFC activity in alcohol-exposed mice.
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Affiliation(s)
- Rafael Renteria
- Department of Psychology, University of California San Diego, San Diego, United States
| | - Christian Cazares
- The Neurosciences Graduate Program, University of California San Diego, San Diego, United States
| | - Emily T Baltz
- The Neurosciences Graduate Program, University of California San Diego, San Diego, United States
| | - Drew C Schreiner
- Department of Psychology, University of California San Diego, San Diego, United States
| | - Ege A Yalcinbas
- The Neurosciences Graduate Program, University of California San Diego, San Diego, United States
| | - Thomas Steinkellner
- Department of Neurosciences, University of California San Diego, San Diego, United States
| | - Thomas S Hnasko
- The Neurosciences Graduate Program, University of California San Diego, San Diego, United States.,Department of Neurosciences, University of California San Diego, San Diego, United States.,Research Service, VA San Diego Healthcare System, San Diego, United States
| | - Christina M Gremel
- Department of Psychology, University of California San Diego, San Diego, United States.,The Neurosciences Graduate Program, University of California San Diego, San Diego, United States
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9
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Hurel I, Muguruza C, Redon B, Marsicano G, Chaouloff F. Cannabis and exercise: Effects of Δ 9-tetrahydrocannabinol on preference and motivation for wheel-running in mice. Prog Neuropsychopharmacol Biol Psychiatry 2021; 105:110117. [PMID: 32971218 DOI: 10.1016/j.pnpbp.2020.110117] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 09/11/2020] [Accepted: 09/20/2020] [Indexed: 11/27/2022]
Abstract
Recent surveys have revealed close links between cannabis and exercise. Specifically, cannabis usage before and/or after exercise is an increasingly common habit primarily aimed at boosting exercise pleasure, motivation, and performance whilst facilitating post-exercise recovery. However, whether these beliefs reflect the true impact of cannabis on these aspects of exercise is unknown. This study has thus examined the effects of cannabis' main psychoactive ingredient, namely Δ9-tetrahydrocannabinol (THC), on (i) mouse wheel-running preference and performance and (ii) running motivation and seeking behaviour. Wheel-running preference and performance were investigated using a T-maze with free and locked wheels located at the extremity of either arm. Running motivation and seeking were assessed by a cued-running operant task wherein wheel-running was conditioned by nose poking. Moreover, because THC targets cannabinoid type 1 (CB1) receptors, i.e. receptors previously documented to control running motivation, this study also assessed the role of these receptors in running preference, performance, and craving-like behaviour. Whilst acute blockade or genetic deletion of CB1 receptors decreased running preference and performance in the T-maze, THC proved ineffective on either variable. The failure of THC to affect running variables in the T-maze extended to running motivation, as assessed by cued-running under a progressive ratio (PR) reinforcement schedule. This ineffectiveness of THC was not related to the treatment protocol because it successfully increased motivation for palatable food. Although craving-like behaviour, as indexed by a cue-induced reinstatement of running seeking, was found to depend on CB1 receptors, THC again proved ineffective. Neither running motivation nor running seeking were affected when CB1 receptors were further stimulated by increasing the levels of the endocannabinoid 2-arachidonoylglycerol. These results, which suggest that the drive for running is insensitive to the acute stimulation of CB1 receptors, raise the hypothesis that cannabis is devoid of effect on exercise motivation. Future investigation using chronic administration of THC, with and without other cannabis ingredients (e.g. cannabidiol), is however required before conclusions can be drawn.
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Affiliation(s)
- Imane Hurel
- Endocannabinoids and NeuroAdaptation, NeuroCentre INSERM U1215, 33077 Bordeaux, France; Université de Bordeaux, 33077 Bordeaux, France
| | - Carolina Muguruza
- Endocannabinoids and NeuroAdaptation, NeuroCentre INSERM U1215, 33077 Bordeaux, France; Université de Bordeaux, 33077 Bordeaux, France; Department of Pharmacology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Spain
| | - Bastien Redon
- Endocannabinoids and NeuroAdaptation, NeuroCentre INSERM U1215, 33077 Bordeaux, France; Université de Bordeaux, 33077 Bordeaux, France
| | - Giovanni Marsicano
- Endocannabinoids and NeuroAdaptation, NeuroCentre INSERM U1215, 33077 Bordeaux, France; Université de Bordeaux, 33077 Bordeaux, France
| | - Francis Chaouloff
- Endocannabinoids and NeuroAdaptation, NeuroCentre INSERM U1215, 33077 Bordeaux, France; Université de Bordeaux, 33077 Bordeaux, France.
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10
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Hill ML, Nichter B, Loflin M, Norman SB, Pietrzak RH. Comparative associations of problematic alcohol and cannabis use with suicidal behavior in U.S. military veterans: A population-based study. J Psychiatr Res 2021; 135:135-142. [PMID: 33477057 DOI: 10.1016/j.jpsychires.2021.01.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 12/09/2020] [Accepted: 01/04/2021] [Indexed: 12/18/2022]
Abstract
Alcohol use disorder (AUD) and cannabis use disorder (CUD) are each associated with increased suicidal behavior, but it is unclear how their comorbidity relates to suicide risk. Understanding these associations in U.S. military veterans is especially important, given their heightened risk for suicide, high prevalence of AUD, and increasing access to cannabis. We compared associations of probable AUD, CUD, and AUD/CUD with suicide ideation, plan(s), and attempt(s) in a nationally representative sample of 4,069 veterans surveyed in 2019-2020 as part of the National Health and Resilience in Veterans Study. Among veterans who screened positive for current AUD, 8.7% also screened positive for current CUD. Among veterans who screened positive for current CUD, 33.3% screened positive for current AUD. Current and lifetime positive screens for AUD, CUD, and AUD/CUD were each strongly and independently associated with past-year suicide ideation and lifetime suicide ideation, plan(s), and attempt(s) [odds ratios (ORs) = 1.6-8.7]. Relative to veterans who screened positive for AUD only, veterans who screened positive for AUD/CUD and CUD only had higher odds of past-year suicide ideation (AUD/CUD: OR = 3.3; CUD only: OR = 2.4), lifetime suicide ideation (AUD/CUD: OR = 1.9; CUD only: OR = 2.6) and lifetime suicide plan(s) (AUD/CUD: OR = 1.7; CUD only: OR = 6.1). Collectively, findings suggest that screening positive for CUD might be an especially strong indicator of suicide ideation and planning in veterans with and without AUD, independent of sociodemographic, military, trauma, and other psychiatric factors. These findings underscore the importance of routine screening for CUD in suicide prevention efforts, especially as cannabis becomes more widely available.
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Affiliation(s)
- Melanie L Hill
- Department of Psychiatry, University of California, San Diego, CA, USA; VA San Diego Healthcare System, San Diego, CA, USA.
| | - Brandon Nichter
- Department of Psychiatry, University of California, San Diego, CA, USA
| | - Mallory Loflin
- Department of Psychiatry, University of California, San Diego, CA, USA; VA San Diego Healthcare System, San Diego, CA, USA; National Center for PTSD, White River Junction, VT, USA; VA Center of Excellence for Stress and Mental Health, San Diego, CA, USA
| | - Sonya B Norman
- Department of Psychiatry, University of California, San Diego, CA, USA; VA San Diego Healthcare System, San Diego, CA, USA; National Center for PTSD, White River Junction, VT, USA; VA Center of Excellence for Stress and Mental Health, San Diego, CA, USA
| | - Robert H Pietrzak
- National Center for PTSD, VA Connecticut Healthcare System, West Haven, CT, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
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11
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Gianessi CA, Groman SM, Taylor JR. The effects of fatty acid amide hydrolase inhibition and monoacylglycerol lipase inhibition on habit formation in mice. Eur J Neurosci 2021; 55:922-938. [PMID: 33506530 PMCID: PMC10370500 DOI: 10.1111/ejn.15129] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 01/15/2021] [Accepted: 01/21/2021] [Indexed: 12/31/2022]
Abstract
Emerging data indicate that endocannabinoid signaling is critical to the formation of habitual behavior. Previous work demonstrated that antagonism of cannabinoid receptor type 1 (CB1R) with AM251 during operant training impairs habit formation, but it is not known if this behavioral effect is specific to disrupted signaling of the endocannabinoid ligands anandamide or 2-arachidonoyl glycerol (2-AG). Here, we used selective pharmacological compounds during operant training to determine the impact of fatty acid amide hydrolase (FAAH) inhibition to increase anandamide (and other n-acylethanolamines) or monoacylglycerol lipase (MAGL) inhibition to increase 2-AG levels on the formation of habitual behaviors in mice using a food-reinforced contingency degradation procedure. We found, contrary to our hypothesis, that inhibition of FAAH and of MAGL disrupted the formation of habits. Next, AM251 was administered during training to verify that impaired habit formation could be assessed using contingency degradation. AM251-exposed mice responded at lower rates during training and at higher rates in the test. To understand the inconsistency with published data, we performed a proof-of-principle dose-response experiment to compare AM251 in our vehicle-solution to the published vehicle-suspension on response rates. We found consistent reductions in response rate with increasing doses of AM251 in solution and an inconsistent dose-response relationship with AM251 in suspension. Together, our data suggest that further characterization of the role of CB1R signaling in the formation of habitual responding is warranted and that augmenting endocannabinoids may have clinical utility for prophylactically preventing aberrant habit formation such as that hypothesized to occur in substance use disorders.
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Affiliation(s)
- Carol A Gianessi
- Interdepartmental Neuroscience Program, Yale University Graduate School of Arts and Sciences, New Haven, CT, USA
| | - Stephanie M Groman
- Division of Molecular Psychiatry, Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Jane R Taylor
- Interdepartmental Neuroscience Program, Yale University Graduate School of Arts and Sciences, New Haven, CT, USA.,Division of Molecular Psychiatry, Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA.,Department of Psychology, Yale University, New Haven, CT, USA.,Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA
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12
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Thompson SL, Gianessi CA, O'Malley SS, Cavallo DA, Shi JM, Tetrault JM, DeMartini KS, Gueorguieva R, Pittman B, Krystal JH, Taylor JR, Krishnan-Sarin S. Saracatinib Fails to Reduce Alcohol-Seeking and Consumption in Mice and Human Participants. Front Psychiatry 2021; 12:709559. [PMID: 34531767 PMCID: PMC8438169 DOI: 10.3389/fpsyt.2021.709559] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 08/03/2021] [Indexed: 11/13/2022] Open
Abstract
More effective treatments to reduce pathological alcohol drinking are needed. The glutamatergic system and the NMDA receptor (NMDAR), in particular, are implicated in behavioral and molecular consequences of chronic alcohol use, making the NMDAR a promising target for novel pharmacotherapeutics. Ethanol exposure upregulates Fyn, a protein tyrosine kinase that indirectly modulates NMDAR signaling by phosphorylating the NR2B subunit. The Src/Fyn kinase inhibitor saracatinib (AZD0530) reduces ethanol self-administration and enhances extinction of goal-directed ethanol-seeking in mice. However, less is known regarding how saracatinib affects habitual ethanol-seeking. Moreover, no prior studies have assessed the effects of Src/Fyn kinase inhibitors on alcohol-seeking or consumption in human participants. Here, we tested the effects of saracatinib on alcohol consumption and craving/seeking in two species, including the first trial of an Src/Fyn kinase inhibitor to reduce drinking in humans. Eighteen male C57BL/6NCrl mice underwent operant conditioning on a variable interval schedule to induce habitual responding for 10% ethanol/0.1% saccharin. Next, mice received 5 mg/kg saracatinib or vehicle 2 h or 30 min prior to contingency degradation to measure habitual responding. In the human study, 50 non-treatment seeking human participants who drank heavily and met DSM-IV criteria for alcohol abuse or dependence were randomized to receive 125 mg/day saracatinib (n = 33) or placebo (n = 17). Alcohol Drinking Paradigms (ADP) were completed in a controlled research setting: before and after 7-8 days of treatment. Each ADP involved consumption of a priming drink of alcohol (0.03 mg%) followed by ad libitum access (3 h) to 12 additional drinks (0.015 g%); the number of drinks consumed and craving (Alcohol Urge Questionnaire) were recorded. In mice, saracatinib did not affect habitual ethanol seeking or consumption at either time point. In human participants, no significant effects of saracatinib on alcohol craving or consumption were identified. These results in mice and humans suggest that Fyn kinase inhibition using saracatinib, at the doses tested here, may not reduce alcohol consumption or craving/seeking among those habitually consuming alcohol, in contrast to reports of positive effects of saracatinib in individuals that seek ethanol in a goal-directed manner. Nevertheless, future studies should confirm these negative findings using additional doses and schedules of saracatinib administration.
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Affiliation(s)
- Summer L Thompson
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Carol A Gianessi
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States.,Interdepartmental Neuroscience Program, Yale University Graduate School of Arts and Sciences, New Haven, CT, United States
| | - Stephanie S O'Malley
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Dana A Cavallo
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Julia M Shi
- Program in Addiction Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, United States
| | - Jeanette M Tetrault
- Program in Addiction Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, United States
| | - Kelly S DeMartini
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Ralitza Gueorguieva
- Department of Biostatistics, Yale University School of Public Health, New Haven, CT, United States
| | - Brian Pittman
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - John H Krystal
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States.,Department of Neuroscience, Yale University School of Medicine, New Haven, CT, United States
| | - Jane R Taylor
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States.,Department of Neuroscience, Yale University School of Medicine, New Haven, CT, United States.,Department of Psychology, Yale University, New Haven, CT, United States
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13
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Luján MÁ, Cheer JF, Melis M. Choosing the right drug: status and future of endocannabinoid research for the prevention of drug-seeking reinstatement. Curr Opin Pharmacol 2020; 56:29-38. [PMID: 33068883 DOI: 10.1016/j.coph.2020.08.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 08/06/2020] [Accepted: 08/25/2020] [Indexed: 12/21/2022]
Abstract
Prolonged exposure to drugs of abuse leads to severe alterations in mesocorticolimbic dopamine circuitry deeply implicated in substance use disorders. Despite considerable efforts, few medications to reduce relapse rates are currently available. To solve this issue, researchers are uncovering therapeutic opportunities offered by the endocannabinoid system. The cannabinoid receptor type 1 (CB1R), and its endogenous ligands, participate in orchestration of cue-triggered and stress-triggered responses leading to obtain natural and drug rewards. Here, we review the evidence supporting the use of CB1R neutral antagonists, allosteric modulators, indirect agonists, as well as multi-target compounds, as improved alternatives compared to classical CB1R antagonists. The promising therapeutic value of other substrates participating in endocannabinoid signaling, like peroxisome proliferator-activated receptors, is also covered. Overall, a wide body of pre-clinical evidence avails novel pharmacological strategies interacting with the endocannabinoid system as clinically amenable candidates able to counteract drug-induced dopamine maladaptations contributing to increased risk of relapse.
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Affiliation(s)
- Miguel Á Luján
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Joseph F Cheer
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Miriam Melis
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria, Monserrato, Italy.
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14
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Pavon FJ, Polis I, Stouffer DG, Roberto M, Martin-Fardon R, Rodriguez de Fonseca F, Parsons LH, Serrano A. COX-2 Inhibition Antagonizes Intra-Accumbens 2-Arachidonoylglycerol-Mediated Reduction in Ethanol Self-Administration in Rats. Alcohol Clin Exp Res 2020; 44:2158-2165. [PMID: 32944989 DOI: 10.1111/acer.14456] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 09/01/2020] [Indexed: 12/16/2022]
Abstract
BACKGROUND Ethanol (EtOH) self-administration is particularly sensitive to the modulation of CB1 signaling in the nucleus accumbens (NAc) shell, and EtOH consumption increases extracellular levels of the endogenous cannabinoid CB1 receptor agonist 2-arachidonoyl glycerol (2-AG) in this brain region. Stimulation of CB1 receptor with agonists increases EtOH consumption, suggesting that EtOH-induced increases in 2-AG might sustain motivation for EtOH intake. METHODS In order to further explore this hypothesis, we analyzed the alterations in operant EtOH self-administration induced by intra-NAc shell infusions of 2-AG itself, the CB1 inverse agonist SR141716A, the 2-AG clearance inhibitor URB602, anandamide, and the cyclooxygenase-2 (COX-2) inhibitor nimesulide. RESULTS Surprisingly, self-administration of 10% EtOH was dose-dependently reduced by either intra-NAc shell SR141716A or 2-AG infusions. Similar effects were found by intra-NAc shell infusions of URB602, suggesting again a role for accumbal 2-AG on the modulation of EtOH intake. Intra-NAc shell anandamide did not alter EtOH self-administration, pointing to a specific role for 2-AG in the modulation of EtOH self-administration. Finally, the inhibitory effect of intra-NAc shell 2-AG on EtOH intake was significantly reversed by pretreatment with nimesulide, suggesting that oxidative metabolites of 2-AG might mediate these inhibitory effects on operant self-administration. CONCLUSIONS We propose that 2-AG signaling in the NAc exerts an inhibitory influence on EtOH consumption through a non-CB1 receptor mechanism involving the COX-2 pathway.
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Affiliation(s)
- Francisco J Pavon
- From the, Department of Neuroscience, (FJP, IP, DGS, LHP, AS), The Scripps Research Institute, La Jolla, California, USA.,Instituto de Investigación Biomédica de Málaga, (IBIMA) (FJP, FRF, AS), Hospital Regional Universitario de Málaga, Unidad de Gestión Clínica de Salud Mental, Malaga, Spain
| | - Ilham Polis
- From the, Department of Neuroscience, (FJP, IP, DGS, LHP, AS), The Scripps Research Institute, La Jolla, California, USA
| | - David G Stouffer
- From the, Department of Neuroscience, (FJP, IP, DGS, LHP, AS), The Scripps Research Institute, La Jolla, California, USA
| | - Marisa Roberto
- Department of Molecular Medicine, (MR, RM-F), The Scripps Research Institute, La Jolla, California, USA
| | - Rémi Martin-Fardon
- Department of Molecular Medicine, (MR, RM-F), The Scripps Research Institute, La Jolla, California, USA
| | - Fernando Rodriguez de Fonseca
- Instituto de Investigación Biomédica de Málaga, (IBIMA) (FJP, FRF, AS), Hospital Regional Universitario de Málaga, Unidad de Gestión Clínica de Salud Mental, Malaga, Spain
| | - Loren H Parsons
- From the, Department of Neuroscience, (FJP, IP, DGS, LHP, AS), The Scripps Research Institute, La Jolla, California, USA
| | - Antonia Serrano
- From the, Department of Neuroscience, (FJP, IP, DGS, LHP, AS), The Scripps Research Institute, La Jolla, California, USA.,Instituto de Investigación Biomédica de Málaga, (IBIMA) (FJP, FRF, AS), Hospital Regional Universitario de Málaga, Unidad de Gestión Clínica de Salud Mental, Malaga, Spain
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15
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Barker JM, Bryant KG, Montiel-Ramos A, Goldwasser B, Chandler LJ. Selective Deficits in Contingency-Driven Ethanol Seeking Following Chronic Ethanol Exposure in Male Mice. Alcohol Clin Exp Res 2020; 44:1896-1905. [PMID: 32735737 DOI: 10.1111/acer.14418] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/13/2020] [Accepted: 07/14/2020] [Indexed: 01/02/2023]
Abstract
BACKGROUND People with alcohol use disorders exhibit an overreliance on habitual response strategies which may result from a history of chronic alcohol exposure. Although habits are defined by behavior that persists despite changes in outcome value and in action-outcome relationships, most research investigating the effects of ethanol exposure on habits has focused only on outcome devaluation. A clear understanding of the effects of chronic alcohol exposure on the ability to flexibly update behavior may provide insight into the behavioral deficits that characterize alcohol use disorders. METHODS To dissociate the effects of chronic intermittent ethanol (CIE) exposure on contingency-mediated sucrose versus ethanol seeking, adult male C57Bl/6J mice were assigned to 2 separate experiments. In the first experiment, mice were trained to self-administer ethanol prior to 2 cycles of interleaved CIE exposure by vapor inhalation. In a second experiment, mice were trained to self-administer sucrose and ethanol in separate training sessions prior to 4 cycles of interleaved CIE. The use of contingencies to mediate reward seeking was assessed using a contingency degradation paradigm. RESULTS In mice trained to self-administer only ethanol, 2 weeks of CIE resulted in escalated self-administration. At this time point, CIE-exposed mice, but not air-exposed controls, exhibited ethanol seeking that was insensitive to changes in action-outcome contingency, consistent with habitual ethanol seeking. In mice trained to self-administer ethanol and sucrose rewards in sequential sessions, no escalation in self-administration across 4 weeks of CIE was observed. Under these conditions, neither Air- nor CIE-exposed mice reduced ethanol seeking in response to contingency degradation. In contrast, sucrose seeking remained goal-directed. CONCLUSIONS Our results suggest that chronic ethanol exposure impairs contingency-driven ethanol seeking more readily than sucrose-seeking behavior. Further, these findings indicate that the transition from contingency-mediated ethanol seeking occurs more rapidly than for sucrose seeking under similar ethanol exposure conditions.
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Affiliation(s)
- Jacqueline M Barker
- From the, Department of Pharmacology and Physiology (JMB, KGB), Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Kathleen G Bryant
- From the, Department of Pharmacology and Physiology (JMB, KGB), Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Alan Montiel-Ramos
- Department of Neurosciences (AM, BG, LJC), Medical University of South Carolina, Charleston, South Carolina, USA
| | - Benjamin Goldwasser
- Department of Neurosciences (AM, BG, LJC), Medical University of South Carolina, Charleston, South Carolina, USA
| | - Lawrence Judson Chandler
- Department of Neurosciences (AM, BG, LJC), Medical University of South Carolina, Charleston, South Carolina, USA
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16
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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.
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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
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17
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Abstract
Substance use disorder (SUD) is a major public health crisis worldwide, and effective treatment options are limited. During the past 2 decades, researchers have investigated the impact of a variety of pharmacological approaches to treat SUD, one of which is the use of medical cannabis or cannabinoids. Significant progress was made with the discovery of rimonabant, a selective CB1 receptor (CB1R) antagonist (also an inverse agonist), as a promising therapeutic for SUDs and obesity. However, serious adverse effects such as depression and suicidality led to the withdrawal of rimonabant (and almost all other CB1R antagonists/inverse agonists) from clinical trials worldwide in 2008. Since then, much research interest has shifted to other cannabinoid-based strategies, such as peripheral CB1R antagonists/inverse agonists, neutral CB1R antagonists, allosteric CB1R modulators, CB2R agonists, fatty acid amide hydrolase (FAAH) inhibitors, monoacylglycerol lipase (MAGL) inhibitors, fatty acid binding protein (FABP) inhibitors, or nonaddictive phytocannabinoids with CB1R or CB2R-binding profiles, as new therapeutics for SUDs. In this article, we first review recent progress in research regarding the endocannabinoid systems, cannabis reward versus aversion, and the underlying receptor mechanisms. We then review recent progress in cannabinoid-based medication development for the treatment of SUDs. As evidence continues to accumulate, neutral CB1R antagonists (such as AM4113), CB2R agonists (JWH133, Xie2-64), and nonselective phytocannabinoids (cannabidiol, β-caryophyllene, ∆9-tetrahydrocannabivarin) have shown great therapeutic potential for SUDs, as shown in experimental animals. Several cannabinoid-based medications (e.g., dronabinol, nabilone, PF-04457845) that entered clinical trials have shown promising results in reducing withdrawal symptoms in cannabis and opioid users.
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Affiliation(s)
- Ewa Galaj
- Addiction Biology Unit, Molecular Targets and Medication Discoveries Branch, Intramural Research Program, National Institute on Drug Abuse, Baltimore, MD, 21224, USA
| | - Zheng-Xiong Xi
- Addiction Biology Unit, Molecular Targets and Medication Discoveries Branch, Intramural Research Program, National Institute on Drug Abuse, Baltimore, MD, 21224, USA.
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