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Moore CF, Zamarripa CA, Weerts EM. Oral Cannabidiol does not alter Alcohol Seeking and Self-Administration in Baboons. Drug Alcohol Depend 2023; 245:109829. [PMID: 36871377 PMCID: PMC10033431 DOI: 10.1016/j.drugalcdep.2023.109829] [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: 01/06/2023] [Revised: 02/16/2023] [Accepted: 02/17/2023] [Indexed: 03/07/2023]
Abstract
BACKGROUND The cannabinoid cannabidiol (CBD) is currently under investigation as a pharmacotherapy for alcohol use disorder. The aim of the present study was to examine whether acute and chronic treatment with pure CBD would decrease alcohol seeking and consumption behaviors or alter drinking patterns in male baboons with extensive histories of daily alcohol intake (1 g/kg/day). METHODS Seven male baboons self-administered oral alcohol (4% w/v) in a validated chained schedule of reinforcement (CSR) procedure that modeled periods of anticipation, seeking, and consumption. In Experiment 1, CBD (5-40 mg/kg) or vehicle (peanut oil, USP) was administered orally 15- or 90-minutes prior to the start of the session. In Experiment 2, oral doses of CBD (10-40 mg/kg) or vehicle were administered for 5 consecutive days during ongoing alcohol access under the CSR. In addition, behavioral observations were conducted to assess potential drug side effects (e.g., sedation, motor incoordination) following chronic CBD treatment immediately after the session and 24-hours after drug administration. RESULTS Across both experiments, baboons self-administered an average of 1 g/kg/day of alcohol under baseline conditions. Administration of acute or chronic CBD (150-1200 mg total CBD dose/day) that encompassed the purported therapeutic dose range did not significantly reduce alcohol seeking, self-administration or intake (g/kg). Drinking patterns (i.e., number of drinks/bouts, bout duration, nor interdrink interval) also were not altered. There were no observable behavioral disruptions following CBD treatment. CONCLUSIONS In sum, the current data do not support use of pure CBD as an effective pharmacotherapy to reduce ongoing excessive drinking.
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Affiliation(s)
| | - C Austin Zamarripa
- Behavioral Pharmacology Research Unit, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 5510 Nathan Shock Dr., Baltimore, MD 21224, USA
| | - Elise M Weerts
- Division of Behavioral Biology, USA; Behavioral Pharmacology Research Unit, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 5510 Nathan Shock Dr., Baltimore, MD 21224, USA.
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2
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Kamens HM, Flarend G, Horton WJ. The role of nicotinic receptors in alcohol consumption. Pharmacol Res 2023; 190:106705. [PMID: 36813094 PMCID: PMC10083870 DOI: 10.1016/j.phrs.2023.106705] [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: 12/13/2022] [Revised: 02/14/2023] [Accepted: 02/19/2023] [Indexed: 02/22/2023]
Abstract
The use of alcohol causes significant morbidity and mortality across the globe. Alcohol use disorder (AUD) is defined by the excessive use of this drug despite a negative impact on the individual's life. While there are currently medications available to treat AUD, they have limited efficacy and several side effects. As such, it is essential to continue to look for novel therapeutics. One target for novel therapeutics is nicotinic acetylcholine receptors (nAChRs). Here we systematically review the literature on the involvement of nAChRs in alcohol consumption. Data from both genetic and pharmacology studies provide evidence that nAChRs modulate alcohol intake. Interestingly, pharmacological modulation of all nAChR subtypes examined can decrease alcohol consumption. The reviewed literature demonstrates that nAChRs should continue to be investigated as novel therapeutics for AUD.
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Affiliation(s)
- Helen M Kamens
- Department of Biobehavioral Health, The Pennsylvania State University, University Park, PA 16802, United States.
| | - Geneva Flarend
- Department of Biobehavioral Health, The Pennsylvania State University, University Park, PA 16802, United States
| | - William J Horton
- Department of Biobehavioral Health, The Pennsylvania State University, University Park, PA 16802, United States
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3
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Decker S, Davis G, Vahora I, Vukovic A, Patel P, Suryanarayanan A. Desformylflustrabromine (dFBr), a positive allosteric modulator of α4β2 nicotinic acetylcholine receptors decreases voluntary ethanol consumption and preference in male and female Sprague-Dawley rats. PLoS One 2022; 17:e0273715. [PMID: 36084045 PMCID: PMC9462806 DOI: 10.1371/journal.pone.0273715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 08/11/2022] [Indexed: 11/19/2022] Open
Abstract
Alcohol use disorder is a medical condition that impacts millions of individuals worldwide. Although there are a few pharmacotherapeutic options for alcohol-dependent individuals; there is a need for the development of novel and more effective therapeutic approaches. Alcohol and nicotine are commonly co-abused, and there is evidence that neuronal nicotinic acetylcholine receptors (nAChRs) play a role in both alcohol and nicotine dependence. Desformylflustrabromine (dFBr), a positive allosteric modulator of the α4β2 nAChRs has been shown to reduce nicotine intake, compulsive-like behavior and neuropathic pain in animal models. dFBr has also been previously shown to cross the blood-brain-barrier. We have recently shown that dFBr can attenuate the response to an acute, hypnotic dose of ethanol, via β2 nAchR. Here, we have investigated the effect of dFBr in modulating ethanol consumption using the intermittent access two-bottle choice (IA2BC) model of voluntary ethanol consumption in male and female Sprague Dawley rats. We show that dFBr selectively reduced ethanol but not sucrose consumption in the IA2BC model. Furthermore, dFBr decreased preference for ethanol in both male and female rats. No rebound increase in ethanol intake was observed after the washout period after dFBr treatment. The ability of dFBr to decrease ethanol consumption, along with its previously demonstrated ability to decrease nicotine self-administration in rodents, suggest that dFBr is an attractive therapeutic candidate to target both nicotine and alcohol abuse.
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Affiliation(s)
- Steven Decker
- Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, University of the Sciences, Philadelphia, PA, United States of America
| | - Gregory Davis
- Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, University of the Sciences, Philadelphia, PA, United States of America
| | - Imran Vahora
- Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, University of the Sciences, Philadelphia, PA, United States of America
| | - Alen Vukovic
- Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, University of the Sciences, Philadelphia, PA, United States of America
| | - Parth Patel
- Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, University of the Sciences, Philadelphia, PA, United States of America
| | - Asha Suryanarayanan
- Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, University of the Sciences, Philadelphia, PA, United States of America
- * E-mail:
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4
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Piacentino D, Grant-Beurmann S, Vizioli C, Li X, Moore CF, Ruiz-Rodado V, Lee MR, Joseph PV, Fraser CM, Weerts EM, Leggio L. Gut microbiome and metabolome in a non-human primate model of chronic excessive alcohol drinking. Transl Psychiatry 2021; 11:609. [PMID: 34853299 PMCID: PMC8636625 DOI: 10.1038/s41398-021-01728-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 10/27/2021] [Accepted: 11/05/2021] [Indexed: 02/08/2023] Open
Abstract
A relationship between the gut microbiome and alcohol use disorder has been suggested. Excessive alcohol use produces changes in the fecal microbiome and metabolome in both rodents and humans. Yet, these changes can be observed only in a subgroup of the studied populations, and reversal does not always occur after abstinence. We aimed to analyze fecal microbial composition and function in a translationally relevant baboon model of chronic heavy drinking that also meets binge criteria (drinking too much, too fast, and too often), i.e., alcohol ~1 g/kg and blood alcohol levels (BALs) ≥ 0.08 g/dL in a 2-hour period, daily, for years. We compared three groups of male baboons (Papio anubis): L = Long-term alcohol drinking group (12.1 years); S = Short-term alcohol drinking group (2.7 years); and C = Control group, drinking a non-alcoholic reinforcer (Tang®) (8.2 years). Fecal collection took place during 3 days of Drinking (D), followed by a short period (3 days) of Abstinence (A). Fecal microbial alpha- and beta-diversity were significantly lower in L vs. S and C (p's < 0.05). Members of the commensal families Lachnospiraceae and Prevotellaceae showed a relative decrease, whereas the opportunistic pathogen Streptococcus genus showed a relative increase in L vs. S and C (p's < 0.05). Microbiota-related metabolites of aromatic amino acids, tricarboxylic acid cycle, and pentose increased in L vs. S and C (FDR-corrected p < 0.01), with the latter two suggesting high energy metabolism and enhanced glycolysis in the gut lumen in response to alcohol. Consistent with the long-term alcohol exposure, mucosal damage and oxidative stress markers (N-acetylated amino acids, 2-hydroxybutyrate, and metabolites of the methionine cycle) increased in L vs. S and C (FDR-corrected p < 0.01). Overall, S showed few differences vs. C, possibly due to the long-term, chronic alcohol exposure needed to alter the normal gut microbiota. In the three groups, the fecal microbiome barely differed between conditions D and A, whereas the metabolome shifted in the transition from condition D to A. In conclusion, changes in the fecal microbiome and metabolome occur after significant long-term excessive drinking and are only partially affected by acute forced abstinence from alcohol. These results provide novel information on the relationship between the fecal microbiome and metabolome in a controlled experimental setting and using a unique non-human primate model of chronic excessive alcohol drinking.
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Affiliation(s)
- Daria Piacentino
- grid.94365.3d0000 0001 2297 5165Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, 251 Bayview Blvd, Baltimore, MD 21224 USA ,grid.94365.3d0000 0001 2297 5165Center on Compulsive Behaviors, National Institutes of Health, 10 Center Dr, Bethesda, MD 20892 USA
| | - Silvia Grant-Beurmann
- grid.411024.20000 0001 2175 4264Institute for Genome Sciences, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD USA
| | - Carlotta Vizioli
- grid.420085.b0000 0004 0481 4802Sensory Science and Metabolism Unit, National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research and National Institute of Nursing Research Division of Intramural Research, 10 Center Dr, Bethesda, MD 20892 USA
| | - Xiaobai Li
- grid.94365.3d0000 0001 2297 5165Biostatistics and Clinical Epidemiology Services, National Institutes of Health, Bethesda, MD USA
| | - Catherine F. Moore
- grid.21107.350000 0001 2171 9311Division of Behavioral Biology, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Nathan Shock Drive, Baltimore, MD 21224 USA
| | - Victor Ruiz-Rodado
- grid.94365.3d0000 0001 2297 5165Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, 10 Center Dr, Bethesda, MD 20892 USA
| | - Mary R. Lee
- grid.94365.3d0000 0001 2297 5165Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, 251 Bayview Blvd, Baltimore, MD 21224 USA
| | - Paule V. Joseph
- grid.420085.b0000 0004 0481 4802Sensory Science and Metabolism Unit, National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research and National Institute of Nursing Research Division of Intramural Research, 10 Center Dr, Bethesda, MD 20892 USA
| | - Claire M. Fraser
- grid.411024.20000 0001 2175 4264Institute for Genome Sciences, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD USA
| | - Elise M. Weerts
- grid.21107.350000 0001 2171 9311Division of Behavioral Biology, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Nathan Shock Drive, Baltimore, MD 21224 USA
| | - Lorenzo Leggio
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, 251 Bayview Blvd, Baltimore, MD, 21224, USA. .,Center on Compulsive Behaviors, National Institutes of Health, 10 Center Dr, Bethesda, MD, 20892, USA. .,Medication Development Program, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, 251 Bayview Blvd, Baltimore, MD, 21224, USA. .,Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, Brown University School of Public Health, 121 South Main Street, Providence, RI, USA. .,Division of Addiction Medicine, Department of Medicine, Johns Hopkins University School of Medicine, 733 N Broadway, Baltimore, MD, 21205, USA. .,Department of Neuroscience, Georgetown University Medical Center, 3970 Reservoir Rd NW, Washington, DC, 20007, USA.
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Miller CN, Kamens HM. The role of nicotinic acetylcholine receptors in alcohol-related behaviors. Brain Res Bull 2020; 163:135-142. [PMID: 32707263 DOI: 10.1016/j.brainresbull.2020.07.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 06/23/2020] [Accepted: 07/17/2020] [Indexed: 12/29/2022]
Abstract
Alcohol use disorder (AUD) causes an alarming economic and health burden in the United States. Unfortunately, this disease does not exist in isolation; AUD is highly comorbid with nicotine use. Results from both human and animal models demonstrate a genetic correlation between alcohol and nicotine behaviors. These data support the idea of shared genetic and neural mechanisms underlying these behaviors. Nicotine acts directly at nicotinic acetylcholine receptors (nAChR) to have its pharmacological effect. Interestingly, alcohol also acts both directly and indirectly at these receptors. Research utilizing genetically engineered rodents and pharmacological manipulations suggest a role for nAChR in several ethanol behaviors. The current manuscript collates this literature and discusses findings that implicate specific nAChR subunits in ethanol phenotypes. These data suggest future directions for targeting nAChR as novel therapeutics for AUD.
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Affiliation(s)
- C N Miller
- Department of Biobehavioral Health, The Pennsylvania State University, University Park, PA, 16802, United States
| | - H M Kamens
- Department of Biobehavioral Health, The Pennsylvania State University, University Park, PA, 16802, United States.
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Chandler CM, Maggio SE, Peng H, Nixon K, Bardo MT. Effects of ethanol, naltrexone, nicotine and varenicline in an ethanol and nicotine co-use model in Sprague-Dawley rats. Drug Alcohol Depend 2020; 212:107988. [PMID: 32387915 PMCID: PMC7293937 DOI: 10.1016/j.drugalcdep.2020.107988] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 03/18/2020] [Accepted: 03/18/2020] [Indexed: 01/02/2023]
Abstract
BACKGROUND As alcohol and nicotine use disorders are entwined, it may be possible to develop a single medication to treat both. We previously developed a model for ethanol (EtOH) and nicotine co-use in female selectively bred alcohol-preferring (P) rats. To model co-use in a genetically diverse population, we adapted the model to outbred Sprague-Dawley rats of both sexes and assessed the effect of drug pretreatments. METHODS In phase 1, rats were trained in a 2-bottle choice between water and a sweetened or unsweetened EtOH solution in operant chambers. In phase 2, rats were trained in nicotine self-administration under an increasing fixed ratio (FR) schedule with 2 bottles containing water or saccharin-sweetened EtOH also available. In phase 3, rats were pretreated with EtOH (0.5, 1.5 g/kg), naltrexone (0.3 mg/kg), nicotine (0.2, 0.6 mg/kg), varenicline (3.0 mg/kg) or vehicle before the session. RESULTS Sweetening the EtOH solution was required to obtain pharmacologically relevant levels of consumption in Phase 1, with males showing increased sweetened EtOH preference compared to females. In Phase 2, increasing the FR requirement for nicotine decreased nicotine infusions, but increased EtOH consumption. In Phase 3, EtOH, naltrexone, and nicotine failed to alter EtOH consumption; however, varenicline decreased both EtOH and nicotine intake. CONCLUSIONS The co-use model was successfully adapted to Sprague-Dawley rats by adding saccharin to the EtOH solution. In contrast to previous results in P rats, varenicline reduced both EtOH and nicotine intake, indicating it may be a useful monotherapy for co-use in a genetically diverse population.
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Affiliation(s)
- Cassie M Chandler
- Department of Psychology, University of Kentucky, 106 B, Kastle Hall, Lexington, KY 40536, USA
| | - Sarah E Maggio
- Department of Psychology, University of Kentucky, 106 B, Kastle Hall, Lexington, KY 40536, USA
| | - Hui Peng
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Kimberly Nixon
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA
| | - Michael T Bardo
- Department of Psychology, University of Kentucky, 106 B, Kastle Hall, Lexington, KY 40536, USA.
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Efficacy of Varenicline in Patients With Severe Alcohol Dependence: A Pilot Double-Blind Randomized and Controlled Study. J Clin Psychopharmacol 2020; 39:398-402. [PMID: 31188242 DOI: 10.1097/jcp.0000000000001056] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE/BACKGROUND Varenicline has proven its efficacy in the treatment of nicotine dependence, and there is also evidence that it could be helpful in the treatment of alcohol dependence. In our pilot study, we investigated the feasibility and acceptability of varenicline for the treatment of a population of patients with severe alcohol dependence and multiple somatic comorbidities after alcohol detoxification. METHODS/PROCEDURES We conducted a phase II, double-blind, placebo-controlled randomized trial of daily oral varenicline versus a placebo in alcohol-dependent men and women after alcohol detoxification (n = 28). Following our study protocol, somatic conditions and adverse events were thoroughly monitored and several study end points were investigated (percentage of abstinent days for both alcohol and nicotine, number of standardized drinks and cigarettes per day, days of heavy drinking). FINDINGS/RESULTS Compared with the placebo, varenicline did not have more side effects and did not provoke more adverse events. Patients in the varenicline group did not show a significantly higher percentage of alcohol abstinent days or fewer heavy drinking days. A trend significance was found for a reduced number of standard drinks per day (P = 0.06) in the varenicline group. IMPLICATIONS/CONCLUSIONS In this pilot trial, varenicline was shown to be well tolerated by our study population of severely alcohol-dependent patients with somatic conditions. Varenicline did not sustain alcohol abstinence or reduce the number of heavy drinking days, but it did reduce the daily amount of alcohol consumed.
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8
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Holtyn AF, Davis CM, Weerts EM. Development of a novel alcohol and nicotine concurrent access (ANCA) self-administration procedure in baboons. Drug Alcohol Depend 2020; 206:107665. [PMID: 31801108 PMCID: PMC6980761 DOI: 10.1016/j.drugalcdep.2019.107665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 09/03/2019] [Accepted: 09/22/2019] [Indexed: 10/25/2022]
Abstract
BACKGROUND Self-administration of either alcohol or nicotine under single-access conditions has been studied extensively in laboratory animals. Relatively few studies have examined the co-use of these substances, even though alcohol and nicotine use and abuse commonly co-occur in humans. The objectives of this study were to develop a baboon model of concurrent alcohol and nicotine self-administration, and examine effects of varenicline on alcohol and nicotine co-use. METHODS In Experiment 1, five male baboons were trained to self-administer drinks of alcohol (4% w/v) and injections of nicotine (0.032-0.1 mg/kg) under single-access and then concurrent-access conditions, and intake of alcohol (g/kg) and nicotine (mg/kg) was compared under single- and concurrent-access conditions. In Experiment 2, three male baboons self-administered drinks of alcohol (4% w/v) and injections of nicotine (0.056 mg/kg) under concurrent-access conditions. Pretreatment with varenicline (0.32-1.0 mg/kg, s.c.) or an equal volume of its vehicle before concurrent-access sessions was repeated for 5 consecutive days. RESULTS Self-administration of nicotine and alcohol was successfully established under both single- and concurrent-access conditions that produced reliable levels of voluntary alcohol and nicotine intake. Co-self-administration of both drugs produced levels of intake similar to that produced by each drug alone. Varenicline significantly reduced intake of both alcohol and nicotine when compared to the vehicle condition. CONCLUSIONS This baboon model provides a valuable tool for further investigation of the behavioral and pharmacological mechanisms involved in co-use of nicotine and alcohol. A single pharmacotherapeutic agent (e.g., varenicline) may be useful in treating nicotine and alcohol co-use.
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Holtyn AF, Weerts EM. Evaluation of mifepristone effects on alcohol-seeking and self-administration in baboons. Exp Clin Psychopharmacol 2019; 27:227-235. [PMID: 30570274 PMCID: PMC6727199 DOI: 10.1037/pha0000246] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Mifepristone, a type II glucocorticoid receptor antagonist, is under investigation as a potential pharmacotherapy for alcohol use disorder. This study examined effects of chronic administration of mifepristone on alcohol-seeking and self-administration in large nonhuman primates. Adult baboons (n = 5) self-administered alcohol 7 days/week under a chained schedule of reinforcement (CSR). The CSR comprised 3 components in which distinct cues were paired with different schedule requirements, with alcohol available for self-administration only in the final component, to model different phases of alcohol anticipation, seeking, and consumption. Under baseline conditions, baboons self-administered an average of 1g/kg/day of alcohol in the self-administration period. Mifepristone (10, 20, and 30 mg/kg) or vehicle was administered orally 30 min before each CSR session for 7 consecutive days. In a separate group of baboons (n = 5) acute doses of mifepristone (10, 20, and 30 mg/kg) were administered, and blood samples were collected over 72 hr to examine mifepristone pharmacokinetics. Some samples also were collected from the baboons that self-administered alcohol under the CSR after the chronic mifepristone condition. Mifepristone did not alter alcohol-seeking or self-administration under the CSR when compared with the vehicle condition. Mifepristone pharmacokinetics were nonlinear, and appear to be capacity limited. In sum, mifepristone did not reduce alcohol-maintained behaviors when administered to baboons drinking 1g/kg daily. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
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Affiliation(s)
- August F. Holtyn
- Johns Hopkins University School of Medicine, 5200 Eastern Ave, Baltimore, MD 21224, USA
| | - Elise M. Weerts
- Johns Hopkins University School of Medicine, 5510 Nathan Shock Dr, Baltimore, MD 21224, USA
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10
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Bold KW, Zweben A, Fucito LM, Piepmeier ME, Muvvala S, Wu R, Gueorguieva R, O'Malley SS. Longitudinal Findings from a Randomized Clinical Trial of Varenicline for Alcohol Use Disorder with Comorbid Cigarette Smoking. Alcohol Clin Exp Res 2019; 43:937-944. [PMID: 30817018 DOI: 10.1111/acer.13994] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 02/20/2019] [Indexed: 11/27/2022]
Abstract
BACKGROUND This study is the first to examine longitudinal posttreatment outcomes of a placebo-controlled trial of varenicline for alcohol use disorder (AUD) with comorbid cigarette smoking. METHODS Participants were 131 adults (n = 39 female) seeking alcohol treatment in a randomized, double-blind, parallel group, placebo-controlled, 16-week multisite trial of varenicline combined with medical management (MM). Timeline follow-back assessments of alcohol and smoking behavior were conducted at the end of treatment (4 months), with follow-ups at 6, 9, and 12 months. Outcomes were percentage of heavy drinking days (PHDD), percent of participants with no heavy drinking days (NHDD), cotinine-confirmed prolonged smoking abstinence (PA), and good clinical outcome on either NHDD or PA. RESULTS Treatment improvements were maintained posttreatment. For the sample overall, PHDD or NHDD did not differ significantly by treatment condition (ps > 0.13), but varenicline produced higher rates of PA versus placebo at 4, 9, and 12 months (p < 0.05). Significant differences were observed by sex: Males had higher rates of NHDD with varenicline (28.9%) versus placebo (6.4%) at the end of treatment (p = 0.004), and these effects were maintained at 12 months (varenicline: 40.0% vs. placebo: 19.2%, p = 0.03). Higher rates of PA were seen for varenicline in both males (8.9%) and females (21.1%) versus placebo (males/females: 0%) at the end of treatment (p = 0.05), and this effect was maintained at 12 months for females (varenicline: 21.1% vs. placebo, 0.0%, p = 0.05). CONCLUSIONS Varenicline treatment combined with MM appears to have enduring benefits for patients with co-occurring AUD and cigarette smoking, and these effects may differ by sex.
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Affiliation(s)
- Krysten W Bold
- Department of Psychiatry , Yale School of Medicine, New Haven, Connecticut
| | - Allen Zweben
- School of Social Work , Columbia University, New York, New York
| | - Lisa M Fucito
- Department of Psychiatry , Yale School of Medicine, New Haven, Connecticut
| | | | - Srinivas Muvvala
- Department of Psychiatry , Yale School of Medicine, New Haven, Connecticut
| | - Ran Wu
- Department of Psychiatry , Yale School of Medicine, New Haven, Connecticut
| | - Ralitza Gueorguieva
- Department of Psychiatry , Yale School of Medicine, New Haven, Connecticut.,Department of Biostatistics , Yale School of Public Health, New Haven, Connecticut
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Can the use of varenicline improve the efficacy of pharmacotherapy for nicotine addiction? CURRENT PROBLEMS OF PSYCHIATRY 2019. [DOI: 10.2478/cpp-2019-0002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Introduction: Smoking is a huge medical and social problem in Poland, with as many as about 24% of Poles being addicted to nicotine. Approximately 6 million people worldwide die every year from conditions that are closely related to tobacco addiction, such as cancer and cardiovascular, metabolic or lung diseases. The difficulty in combatting nicotine dependence is largely due to the complex mechanism of this addiction. The motivation of a patient to quit smoking is of great importance in the difficult withdrawal process. Strengthening this motivation is one of the most important tasks of physicians and addiction therapists.
Overview of literature: Nicotine replacement therapy (NRT) has been the most widely known way to break away from smoking addiction for many years now. It involves delivering nicotine to the body in ways that are less harmful than through tobacco smoke. As a consequence, the cravings for nicotine are reduced, making it easier for the patient to break with the addiction. Clinical trials have shown that the use of NRT is associated with a 50-70% increased chance of maintaining abstinence from smoking compared to placebo. There are many NRT products, including nicotine chewing gum, nicotine patches, lozenges, dissolvable nicotine sticks, or inhalers. Bupropion is a selective dopamine–noradrenaline reuptake inhibitor. This drug is one of the most commonly used in the pharmacotherapy of depression in the United States. At the same time, it has been found to have a positive effect on people trying to break up with the habit of smoking cigarettes. The mechanism of action remains unknown in this case, but studies clearly indicate the efficacy of bupropion, which is comparable to the efficacy of NRT. Varenicline is a partial agonist selective for α4β2 nicotinic acetylcholine receptors. It has a higher affinity for these receptors than nicotine. By stimulating them, it causes an increase in dopamine secretion (but to a lesser extent than cigarette smoking), helping in this way ease withdrawal symptoms.
Conclusions: Varenicline has higher efficacy than bupropion and NRTs. Simultaneous use of two NRT forms increases the effectiveness of this method to a level comparable to varenicline. Contrary to previous reports, it seems that varenicline does not increase self-aggressive behaviour and the risk of suicide. The effectiveness of antinicotinic drugs depends on the sex of the patient. For both sexes, the most effective drug is varenicline. It is slightly more effective in women than in men. By contrast, NRT and bupropion show greater therapeutic potential in men.
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O’Malley SS, Zweben A, Fucito LM, Wu R, Piepmeier ME, Ockert DM, Bold KW, Petrakis I, Muvvala S, Jatlow P, Gueorguieva R. Effect of Varenicline Combined With Medical Management on Alcohol Use Disorder With Comorbid Cigarette Smoking: A Randomized Clinical Trial. JAMA Psychiatry 2018; 75:129-138. [PMID: 29261824 PMCID: PMC5838706 DOI: 10.1001/jamapsychiatry.2017.3544] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
IMPORTANCE Individuals with alcohol use disorder have high rates of cigarette smoking. Varenicline tartrate, an approved treatment for smoking cessation, may reduce both drinking and smoking. OBJECTIVES To test the efficacy of varenicline with medical management for patients with alcohol use disorder and comorbid smoking seeking alcohol treatment, and to evaluate the secondary effects on smoking abstinence. DESIGN, SETTING, AND PARTICIPANTS This phase 2, randomized, double-blind, parallel group, placebo-controlled trial was conducted at 2 outpatient clinics from September 19, 2012, to August 31, 2015. Eligible participants met alcohol-dependence criteria and reported heavy drinking (≥5 drinks for men and ≥4 drinks for women) 2 or more times per week and smoking 2 or more times per week; 131 participants were randomized to either varenicline or placebo stratified by sex and site. All analyses were of the intention-to-treat type. Data analysis was conducted from February 5, 2016, to September 29, 2017. INTERVENTIONS Varenicline tartrate, 1 mg twice daily, and matching placebo pills for 16 weeks. Medical management emphasized medication adherence for 4 weeks followed by support for changing drinking. MAIN OUTCOMES AND MEASURES Percentage of heavy drinking days (PHDD) weeks 9 to 16, no heavy drinking days (NHDD) weeks 9 to 16, and prolonged smoking abstinence weeks 13 to 16. RESULTS Of 131 participants, 39 (29.8%) were women and 92 (70.2%) were men, the mean (SD) age was 42.7 (11.7) years, and the race/ethnicity self-identified by most respondents was black (69 [52.7%]). Sixty-four participants were randomized to receive varenicline, and 67 to receive placebo. Mean change in PHDD between varenicline and placebo across sex and site was not significantly different. However, a significant treatment by sex by time interaction for PHDD (F1,106 = 4.66; P = .03) revealed that varenicline compared with placebo resulted in a larger decrease in log-transformed PHDD in men (least square [LS] mean difference in change from baseline, 0.54; 95% CI, -0.09 to 1.18; P = .09; Cohen d = 0.45) but a smaller decrease in women (LS mean difference, -0.69; 95% CI, -1.63 to 0.25; P = .15; Cohen d = -0.53). Thirteen of 45 men (29%) had NHDD taking varenicline compared with 3 of 47 men (6%) taking placebo (Cohen h = 0.64; 95% CI, 0.22-1.03), whereas 1 of 19 women (5%) had NHDD compared with 5 of 20 women (25%) taking placebo (Cohen h = -0.60; 95% CI, -1.21 to 0.04). Taking varenicline, 8 of 64 participants (13%) achieved prolonged smoking abstinence; no one (0 of 67) quit smoking taking placebo (P = .003; Cohen h = 0.72; 95% CI, 0.38-1.07). CONCLUSIONS AND RELEVANCE Varenicline with medical management resulted in decreased heavy drinking among men and increased smoking abstinence in the overall sample. Varenicline could be considered to promote improvements in men with these dual behavioral health risks. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01553136.
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Affiliation(s)
| | - Allen Zweben
- School of Social Work, Columbia University, New York, New York
| | - Lisa M. Fucito
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | - Ran Wu
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | | | | | - Krysten W. Bold
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | - Ismene Petrakis
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | - Srinivas Muvvala
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | - Peter Jatlow
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut,Department of Laboratory Medicine, Yale School of Medicine, New Haven, Connecticut
| | - Ralitza Gueorguieva
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut,Department of Biostatistics, Yale School of Public Health, New Haven, Connecticut
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Abstract
Animal models provide rapid, inexpensive assessments of an investigational drug's therapeutic potential. Ideally, they support the plausibility of therapeutic efficacy and provide a rationale for further investigation. Here, I discuss how the absence of clear effective-ineffective categories for alcohol use disorder (AUD) medications and biases in the clinical and preclinical literature affect the development of predictive preclinical alcohol dependence (AD) models. Invoking the analogical argument concept from the philosophy of science field, I discuss how models of excessive alcohol drinking support the plausibility of clinical pharmacotherapy effects. Even though these models are not likely be completely discriminative, they are sensitive to clinically effective medications and have revealed dozens of novel medication targets. In that context, I discuss recent preclinical work on GLP-1 receptor agonists, phosphodiesterase inhibitors, glucocorticoid receptor antagonists, nociception agonists and antagonists, and CRF1 antagonists. Clinically approved medications are available for each of these drug classes. I conclude by advocating a translational approach in which drugs are evaluated highly congruent preclinical models and human laboratory studies. Once translation is established, I suggest the burden is to develop hypothesis-based therapeutic interventions maximizing the impact of the confirmed pharmacotherapeutic effects in the context of additional variables falling outside the model.
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Affiliation(s)
- Mark Egli
- Division of Neuroscience and Behavior, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA.
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14
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Pomrenze MB, Fetterly TL, Winder DG, Messing RO. The Corticotropin Releasing Factor Receptor 1 in Alcohol Use Disorder: Still a Valid Drug Target? Alcohol Clin Exp Res 2017; 41:1986-1999. [PMID: 28940382 PMCID: PMC5711524 DOI: 10.1111/acer.13507] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 09/15/2017] [Indexed: 01/20/2023]
Abstract
Corticotropin releasing factor (CRF) is a neuropeptide that plays a key role in behavioral and physiological responses to stress. A large body of animal literature implicates CRF acting at type 1 CRF receptors (CRFR1) in consumption by alcohol-dependent subjects, stress-induced reinstatement of alcohol seeking, and possibly binge alcohol consumption. These studies have encouraged recent pilot studies of CRFR1 antagonists in humans with alcohol use disorder (AUD). It was a great disappointment to many in the field that these studies failed to show an effect of these compounds on stress-induced alcohol craving. Here, we examine these studies to explore potential limitations and discuss preclinical and human literature to ask whether CRFR1 is still a valid drug target to pursue for the treatment of AUD.
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Affiliation(s)
| | - Tracy L. Fetterly
- Department of Molecular Physiology & Biophysics, Vanderbilt
University, Nashville, TN
- Vanderbilt Neuroscience Graduate Program, Vanderbilt University,
Nashville, TN
| | - Danny G. Winder
- Department of Molecular Physiology & Biophysics, Vanderbilt
University, Nashville, TN
- Vanderbilt Center for Addiction Research, Vanderbilt University,
Nashville, TN
- Vanderbilt Neuroscience Graduate Program, Vanderbilt University,
Nashville, TN
| | - Robert O. Messing
- Institute for Neuroscience, University of Texas at Austin, Austin,
TX
- Departments of Neuroscience and Neurology, University of Texas at
Austin, Austin, TX
- Waggoner Center for Alcohol and Addiction Research, University of
Texas at Austin, Austin, TX
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15
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Holtyn AF, Tiruveedhula VVNPB, Stephen MR, Cook JM, Weerts EM. Effects of the benzodiazepine GABA A α1-preferring antagonist 3-isopropoxy-β-carboline hydrochloride (3-ISOPBC) on alcohol seeking and self-administration in baboons. Drug Alcohol Depend 2017; 170:25-31. [PMID: 27865151 PMCID: PMC5183547 DOI: 10.1016/j.drugalcdep.2016.10.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 10/28/2016] [Accepted: 10/28/2016] [Indexed: 01/09/2023]
Abstract
BACKGROUND The major inhibitory neurotransmitter, gamma-aminobutyric acid (GABA), modulates many of the behavioral effects of alcohol, including sedation, tolerance, and withdrawal. The α1 subunit of the benzodiazepine GABAA receptor is the most widely expressed alpha subunit in the brain, and has been implicated in the reinforcing- and abuse-related effects of alcohol. The aim of the present study was to examine whether treatment with a benzodiazepine GABAA α1-preferring ligand, 3-isopropoxy-β-carboline hydrochloride (3-ISOPBC), selectively decreases alcohol seeking and consumption. METHODS Eight baboons self-administered alcohol (4% w/v; n=5; alcohol group) or a non-alcoholic beverage (n=3; control group) in Component 3 of a chained schedule of reinforcement. Responses in Component 2 provided indices of motivation to drink (seeking). Doses of 3-ISOPBC (5.0-30.0mg/kg) and vehicle were administered before drinking sessions under both acute and chronic (5day) conditions. RESULTS Chronic, and not acute, administration of 3-ISOPBC significantly decreased self-administration responses, g/kg alcohol consumed, and the number of drinks in and duration of the first drinking bout in the alcohol group. In the control group, chronic administration of 3-ISOPBC did not significantly decrease any of these measures at any of the doses. CONCLUSIONS The GABAA α1-preferring ligand 3-ISOPBC may have therapeutic potential in the treatment of alcohol use disorder due to its ability to selectively reduce alcohol use.
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Affiliation(s)
- August F Holtyn
- Johns Hopkins University School of Medicine, Division of Behavioral Biology, 5510 Nathan Shock Dr, Baltimore, MD 21224, USA
| | - V V N Phani Babu Tiruveedhula
- University of Wisconsin-Milwaukee, Department of Chemistry & Biochemistry, 3210 N Cramer St, Milwaukee, WI 53201, USA
| | - Michael Rajesh Stephen
- University of Wisconsin-Milwaukee, Department of Chemistry & Biochemistry, 3210 N Cramer St, Milwaukee, WI 53201, USA
| | - James M Cook
- University of Wisconsin-Milwaukee, Department of Chemistry & Biochemistry, 3210 N Cramer St, Milwaukee, WI 53201, USA
| | - Elise M Weerts
- Johns Hopkins University School of Medicine, Division of Behavioral Biology, 5510 Nathan Shock Dr, Baltimore, MD 21224, USA.
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16
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The effect of varenicline on binge-like ethanol consumption in mice is β4 nicotinic acetylcholine receptor-independent. Neurosci Lett 2016; 633:235-239. [PMID: 27693436 DOI: 10.1016/j.neulet.2016.09.048] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 09/24/2016] [Accepted: 09/26/2016] [Indexed: 12/20/2022]
Abstract
BACKGROUND Our laboratory has previously shown that the smoking-cessation agent varenicline, an agonist/partial agonist of α4β2*, α3β4*, α3β2*, α6β2* (* indicates the possibility of additional subunits) and α7 subunits of nicotinic acetylcholine receptors (nAChRs), reduces ethanol consumption in rats only after long-term exposure (12 weeks). As compounds having partial agonistic activity on α3β4* nAChRs were shown to decrease ethanol consumption in rodents, we assessed here the involvement of the β4 subunit in the effect of varenicline in the reduction of short- and long-term binge-like ethanol drinking in mice. METHODS We used the well-validated drinking-in-the-dark (DID) paradigm to model chronic binge-like ethanol drinking in β4-/- and β4+/+ littermate mice and compare the effect of intraperitoneal injection of varenicline (2mg/kg) on ethanol intake following short- (4 weeks) or long-term (12 weeks) exposure. RESULTS Drinking pattern and amounts of ethanol intake were similar in β4-/- and β4+/+ mice. Interestingly, our results showed that varenicline reduces ethanol consumption following short- and long-term ethanol exposure in the DID. Although the effect of varenicline on the reduction of ethanol consumption was slightly more pronounced in β4-/- mice than their β4+/+ littermates no significant differences were observed between genotypes. CONCLUSION In mice, varenicline reduces binge-like ethanol consumption both after short- and long-term exposure in the DID and this effect is independent of β4 nAChR subunit.
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17
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Kohut SJ. Interactions between nicotine and drugs of abuse: a review of preclinical findings. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 2016; 43:155-170. [PMID: 27589579 DOI: 10.1080/00952990.2016.1209513] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Polysubstance abuse is common among substance-use disorder patients, and nicotine is one of the most commonly co-used substances. Epidemiological and clinical laboratory studies suggest that nicotine, when combined with other drugs of abuse, increases intake of one or both substances. This review focuses on the preclinical literature regarding nicotine's interaction with alcohol, stimulants (i.e., cocaine, amphetamines), opioids (i.e., morphine, heroin), and Δ9-tetrahydrocannabinol (THC). The current understanding of how these various classes of abused drugs may interact with nicotine on behavioral, physiological, and pharmacological indices that may be important in maintaining co-use of one or both substances in human populations are highlighted. Suggestions as to future areas of research and gaps in knowledge are offered.
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Affiliation(s)
- Stephen J Kohut
- a McLean Hospital and Department of Psychiatry, Harvard Medical School , Belmont , MA , USA
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18
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Srisontiyakul J, Kastman HE, Krstew EV, Govitrapong P, Lawrence AJ. The Nicotinic α6-Subunit Selective Antagonist bPiDI Reduces Alcohol Self-Administration in Alcohol-Preferring Rats. Neurochem Res 2016; 41:3206-3214. [PMID: 27573375 DOI: 10.1007/s11064-016-2045-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 08/22/2016] [Accepted: 08/24/2016] [Indexed: 10/21/2022]
Abstract
Cigarettes and alcohol are the most abused substances in the world and are commonly co-abused. Nicotine primarily acts in the brain on nicotinic acetylcholine receptors (nAChR), which are also a target for alcohol. The alpha6 subunit of nAChR is expressed almost exclusively in the brain reward system and may modulate the rewarding properties of alcohol and nicotine. Recently, N,N-decane-1,10-diyl-bis-3-picolinium diiodide (bPiDI) was synthesized as a selective, brain penetrant α6 subunit antagonist that reduces nicotine self-administration. The current study aimed to examine the effects of bPiDI on alcohol self-administration in inbred alcohol-preferring (iP) rats. Adult, male iP rats were trained to self-administer alcohol or sucrose. Once stable responding was achieved, rats were injected with bPiDI (1, 3 mg/kg, i.p.) and tested for self-administration under fixed and progressive ratio schedules of reinforcement. They subsequently underwent extinction, in which no rewards or cues were presented in the operant chambers. Then, they were injected with bPiDI prior to testing for cue-induced reinstatement of reward seeking. bPiDI (3 mg/kg) significantly reduced alcohol self-administration in both fixed and progressive ratios without any effects on sucrose self-administration or locomotor activity. In contrast, bPiDI (3 mg/kg) did not inhibit cue-induced reinstatement of either alcohol or sucrose seeking. The results support the involvement of α6 containing nAChR in reinforcing effects of alcohol, but not relapse to alcohol-seeking, without any impact on responding for a natural reward or general activity. bPiDI may be a potential lead molecule for a therapeutic strategy to limit nicotine and alcohol consumption.
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Affiliation(s)
- Jirawoot Srisontiyakul
- Research Center for Neuroscience, Institute of Molecular Biosciences, Mahidol University, Salaya, Nakhon Pathom, Thailand
| | - Hanna E Kastman
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Royal Parade, Parkville, VIC, 3052, Australia
| | - Elena V Krstew
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Royal Parade, Parkville, VIC, 3052, Australia
| | - Piyarat Govitrapong
- Research Center for Neuroscience, Institute of Molecular Biosciences, Mahidol University, Salaya, Nakhon Pathom, Thailand.,Center for Neuroscience and Department of Pharmacology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Andrew J Lawrence
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Royal Parade, Parkville, VIC, 3052, Australia. .,Florey Department of Neuroscience, University of Melbourne, Parkville, VIC, Australia.
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19
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Obsada N, Zalewska-Kaszubska J. Wareniklina – częściowy agonista receptorów nikotynowych w terapii zespołu uzależnienia od alkoholu. ALCOHOLISM AND DRUG ADDICTION 2016. [DOI: 10.1016/j.alkona.2016.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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20
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Moderators of Varenicline Treatment Effects in a Double-Blind, Placebo-Controlled Trial for Alcohol Dependence: An Exploratory Analysis. J Addict Med 2016; 9:296-303. [PMID: 26083958 DOI: 10.1097/adm.0000000000000133] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVES To explore whether varenicline (Chantix) showed more efficacy in treating certain subgroups of patients. In a recent multisite trial, varenicline was shown to be effective in reducing drinking in alcohol-dependent patients, both smokers and nonsmokers. Given the heterogeneity among alcohol-dependent patients, secondary analyses were conducted to determine whether certain subgroups responded more favorably than others to treatment with varenicline. METHODS Data were drawn from a phase 2 randomized, double-blind, placebo-controlled multisite 13-week trial of varenicline in alcohol-dependent patients (Litten et al., 2013). Seventeen moderator variables were selected for exploratory testing on the basis of theoretical and scientific interest. RESULTS Of the 17 moderator variables assessed, 4 were statistically significant, including cigarettes per day reduction, treatment drinking goal, years drinking regularly, and age of the patient. Two other variables—the type of adverse events experienced by patients and the severity of alcohol-related consequences—seemed to moderate the varenicline treatment effect at borderline statistical significance. Individuals who reduced the number of cigarettes per day experienced a significant effect from varenicline in reducing drinking, whereas those who did not change or who increased their number of cigarettes observed no beneficial effect. Reviewing the moderators related to severity, varenicline seemed to have greater efficacy than placebo among less severely dependent patients. CONCLUSIONS Varenicline seems to be more efficacious in certain subgroups, particularly in those who reduced their smoking and in the "less severe" patient. Additional studies are warranted to confirm the results of these exploratory analyses.
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21
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Helms CM, Bell RL, Bennett AJ, Davies DL, Chester JA, Kosten TA, Leeman RF, Panicker S, Platt DM, Weiner JL, Edwards S. The importance of animals in advancing research on alcohol use disorders. Alcohol Clin Exp Res 2016; 39:575-8. [PMID: 25833015 DOI: 10.1111/acer.12668] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 12/18/2014] [Accepted: 12/30/2014] [Indexed: 01/01/2023]
Affiliation(s)
- Christa M Helms
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon
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22
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Egli M, White DA, Acri JB. Considerations in the Evaluation of Potential Efficacy of Medications for Alcohol and Drug Use Disorders: An Editorial. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2016; 126:1-14. [PMID: 27055609 DOI: 10.1016/bs.irn.2016.02.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
The societal burden created by alcohol and drug use disorders is estimated to be on the order of hundreds of billions of dollars, creating a need for effective medications to reduce use and prevent relapse. While there are FDA-approved medications to facilitate abstinence and prevent relapse for some indications including, alcohol, tobacco, and opiate use disorders, there are no approved treatments for other abused substances, including cocaine, methamphetamine, and cannabis, leaving these critical medical needs unmet. The development of such medications has fallen largely to the government with efforts spearheaded by the National Institute on Drug Abuse and the National Institute on Alcoholism and Alcohol Abuse. Both agencies have medication development programs with preclinical components that include the standardized evaluation of compounds using animal models. This chapter describes the rationale and considerations involved in the use of such models, including reinstatement of drug self-administration.
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Affiliation(s)
- M Egli
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, United States
| | - D A White
- National Institute on Drug Abuse, National Institutes of Health, Bethesda, MD, United States.
| | - J B Acri
- National Institute on Drug Abuse, National Institutes of Health, Bethesda, MD, United States
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23
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Litten RZ, Wilford BB, Falk DE, Ryan ML, Fertig JB. Potential medications for the treatment of alcohol use disorder: An evaluation of clinical efficacy and safety. Subst Abus 2016; 37:286-98. [DOI: 10.1080/08897077.2015.1133472] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Van Skike CE, Maggio SE, Reynolds AR, Casey EM, Bardo MT, Dwoskin LP, Prendergast MA, Nixon K. Critical needs in drug discovery for cessation of alcohol and nicotine polysubstance abuse. Prog Neuropsychopharmacol Biol Psychiatry 2016; 65:269-87. [PMID: 26582145 PMCID: PMC4679525 DOI: 10.1016/j.pnpbp.2015.11.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 11/10/2015] [Accepted: 11/11/2015] [Indexed: 01/29/2023]
Abstract
Polysubstance abuse of alcohol and nicotine has been overlooked in our understanding of the neurobiology of addiction and especially in the development of novel therapeutics for its treatment. Estimates show that as many as 92% of people with alcohol use disorders also smoke tobacco. The health risks associated with both excessive alcohol consumption and tobacco smoking create an urgent biomedical need for the discovery of effective cessation treatments, as opposed to current approaches that attempt to independently treat each abused agent. The lack of treatment approaches for alcohol and nicotine abuse/dependence mirrors a similar lack of research in the neurobiology of polysubstance abuse. This review discusses three critical needs in medications development for alcohol and nicotine co-abuse: (1) the need for a better understanding of the clinical condition (i.e. alcohol and nicotine polysubstance abuse), (2) the need to better understand how these drugs interact in order to identify new targets for therapeutic development and (3) the need for animal models that better mimic this human condition. Current and emerging treatments available for the cessation of each drug and their mechanisms of action are discussed within this context followed by what is known about the pharmacological interactions of alcohol and nicotine. Much has been and will continue to be gained from studying comorbid alcohol and nicotine exposure.
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Affiliation(s)
- C E Van Skike
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, United States
| | - S E Maggio
- Department of Psychology, University of Kentucky, Lexington, KY 40536, United States
| | - A R Reynolds
- Department of Psychology, University of Kentucky, Lexington, KY 40536, United States
| | - E M Casey
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, United States
| | - M T Bardo
- Department of Psychology, University of Kentucky, Lexington, KY 40536, United States; Center for Drug Abuse and Research Translation, University of Kentucky, Lexington, KY 40536, United States; Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536, United States
| | - L P Dwoskin
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, United States; Center for Drug Abuse and Research Translation, University of Kentucky, Lexington, KY 40536, United States
| | - M A Prendergast
- Department of Psychology, University of Kentucky, Lexington, KY 40536, United States; Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536, United States
| | - K Nixon
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, United States; Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536, United States.
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25
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Pittenger ST, Barrett ST, Chou S, Bevins RA. The effects of varenicline on methamphetamine self-administration and drug-primed reinstatement in female rats. Behav Brain Res 2015; 300:150-9. [PMID: 26638833 DOI: 10.1016/j.bbr.2015.11.033] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 11/18/2015] [Accepted: 11/23/2015] [Indexed: 12/14/2022]
Abstract
While research has revealed heightened vulnerability to meth addiction in women, preclinical models rarely use female subjects when investigating meth seeking and relapse. The goal of the present study was to examine the effects of varenicline (Chantix(®)), a partial α4β2 and full α7 nicotinic acetylcholine receptor agonist, on meth self-administration and reinstatement in female rats. Sprague-Dawley rats were surgically implanted with an indwelling jugular catheter. Half of the rats were then trained to self-administer meth (0.056 mg/kg/infusion) on a variable ratio 3 schedule of reinforcement; the other half earned intravenous saline during daily, 2h sessions. When responding stabilized, varenicline (0.0, 0.3, 1.0, 3.0mg/kg) was tested to determine how it altered meth taking. Varenicline was probed on 4 test days; each test separated by 2 standard self-administration sessions to assure responding remained stable. Following this testing was 15 extinction sessions. Twenty-four hours after the last extinction session were four consecutive days of meth-primed reinstatement. The same 4 doses of varenicline were examined to determine how it altered reinstatement triggered by 0.3mg/kg meth (IP). Rats readily self-administered meth. The higher doses of varenicline did not affect meth-taking in a specific fashion as active lever pressing was also slightly reduced in rats that has access to saline in the self-administration phase. Female rats displayed robust meth-primed reinstatement. Notably, the lower doses of varenicline increased meth-primed reinstatement. This amplified susceptibility to reinstatement (i.e., relapse) may be an impediment for the use of varenicline as a therapeutic to treat meth use disorder.
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Affiliation(s)
- Steven T Pittenger
- University of Nebraska-Lincoln, Department of Psychology, 238 Burnett Hall, Lincoln, NE 68588-0308, USA
| | - Scott T Barrett
- University of Nebraska-Lincoln, Department of Psychology, 238 Burnett Hall, Lincoln, NE 68588-0308, USA
| | - Shinnyi Chou
- University of Nebraska-Lincoln, Department of Psychology, 238 Burnett Hall, Lincoln, NE 68588-0308, USA
| | - Rick A Bevins
- University of Nebraska-Lincoln, Department of Psychology, 238 Burnett Hall, Lincoln, NE 68588-0308, USA.
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Rahman S, Engleman EA, Bell RL. Recent Advances in Nicotinic Receptor Signaling in Alcohol Abuse and Alcoholism. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 137:183-201. [PMID: 26810002 PMCID: PMC4754113 DOI: 10.1016/bs.pmbts.2015.10.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Alcohol is the most commonly abused legal substance and alcoholism is a serious public health problem. It is a leading cause of preventable death in the world. The cellular and molecular mechanisms of alcohol reward and addiction are still not well understood. Emerging evidence indicates that unlike other drugs of abuse, such as nicotine, cocaine, or opioids, alcohol targets numerous channel proteins, receptor molecules, and signaling pathways in the brain. Previously, research has identified brain nicotinic acetylcholine receptors (nAChRs), a heterogeneous family of pentameric ligand-gated cation channels expressed in the mammalian brain, as critical molecular targets for alcohol abuse and dependence. Genetic variations encoding nAChR subunits have been shown to increase the vulnerability to develop alcohol dependence. Here, we review recent insights into the rewarding effects of alcohol, as they pertain to different nAChR subtypes, associated signaling molecules, and pathways that contribute to the molecular mechanisms of alcoholism and/or comorbid brain disorders. Understanding these cellular changes and molecular underpinnings may be useful for the advancement of brain nicotinic-cholinergic mechanisms, and will lead to a better translational and therapeutic outcome for alcoholism and/or comorbid conditions.
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Affiliation(s)
- Shafiqur Rahman
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, South Dakota, USA.
| | - Eric A Engleman
- Department of Psychiatry, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Richard L Bell
- Department of Psychiatry, Indiana University School of Medicine, Indianapolis, Indiana, USA
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Randall PA, Jaramillo AA, Frisbee S, Besheer J. The role of varenicline on alcohol-primed self-administration and seeking behavior in rats. Psychopharmacology (Berl) 2015; 232:2443-54. [PMID: 25656746 PMCID: PMC4482789 DOI: 10.1007/s00213-015-3878-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 01/21/2015] [Indexed: 12/30/2022]
Abstract
RATIONALE Varenicline, a smoking-cessation agent, may be useful in treating alcohol use disorders. An important consideration when studying factors that influence drinking/relapse is influence of the pharmacological effects of alcohol on these behaviors. Pre-exposure to alcohol (priming) can increase craving, drinking, and seeking behaviors. OBJECTIVES The primary goal of this work was to determine the effects of varenicline on alcohol-primed self-administration and seeking behavior in male Long-Evans rats. METHODS First, we assessed whether varenicline (0, 0.3, 1, 3 mg/kg, IP) has alcohol-like discriminative stimulus effects and whether varenicline alters sensitivity to alcohol in rats trained to discriminate a moderate alcohol dose (1 g/kg, IG) vs. water. Second, animals trained to self-administer alcohol underwent assessments to test the effects of: (i) varenicline (0, 0.3, 1, 3 mg/kg, IP) on self-administration, (ii) alcohol priming (0, 0.3, 1 g/kg, IG) on self-administration and seeking behavior, and (iii) varenicline (1 mg/kg) in combination with alcohol priming (1 g/kg) on these behaviors. RESULTS Varenicline did not substitute for alcohol but disrupted the expression of sensitivity to alcohol. Varenicline decreased self-administration but only at a motor-impairing dose (3 mg/kg). Alcohol priming decreased self-administration and seeking behavior. Varenicline (1 mg/kg) blocked this effect under self-administration conditions, but not seeking conditions, which effectively resulted in increased alcohol intake. CONCLUSIONS These findings suggest the importance of further behavioral and mechanistic studies to evaluate the use of varenicline in treating alcohol use disorders and its potential impact on drinking patterns in smokers using varenicline as a smoking-cessation aid.
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Affiliation(s)
- Patrick A. Randall
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-7178, USA
| | - Anel A. Jaramillo
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-7178, USA
- Curriculum in Neurobiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-7178, USA
| | - Suzanne Frisbee
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-7178, USA
| | - Joyce Besheer
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-7178, USA
- Curriculum in Neurobiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-7178, USA
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-7178, USA
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Rahman S, Engleman EA, Bell RL. Nicotinic receptor modulation to treat alcohol and drug dependence. Front Neurosci 2015; 8:426. [PMID: 25642160 PMCID: PMC4295535 DOI: 10.3389/fnins.2014.00426] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 12/04/2014] [Indexed: 01/10/2023] Open
Abstract
Alcohol and drug dependence are serious public health problems worldwide. The prevalence of alcohol and drug dependence in the United States and other parts of the world is significant. Given the limitations in the efficacy of current pharmacotherapies to treat these disorders, research in developing alternative pharmacotherapies continues. Preclinical and clinical evidence thus far has indicated that brain nicotinic acetylcholine receptors (nAChRs) are important pharmacological targets for the development of medications to treat alcohol and drug dependence. The nAChRs are a super family of ligand gated ion channels, and are expressed throughout the brain with twelve neuronal nAChR subunits (α2–α10 and β2–β4) identified. Here, we review preclinical and clinical evidence involving a number of nAChR ligands that target different nAChR subtypes in alcohol and nicotine addiction. The important ligands include cytisine, lobeline, mecamylamine, varenicline, sazetidine A and others that target α4β2* nAChR subtypes as small molecule modulators of the brain nicotinic cholinergic system are also discussed. Taken together, both preclinical and clinical data exist that support nAChR–based ligands as promising therapeutic agents for the treatment of alcohol and drug dependence.
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Affiliation(s)
- Shafiqur Rahman
- Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University Brookings, SD, USA
| | - Eric A Engleman
- Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine Indianapolis, IN, USA
| | - Richard L Bell
- Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine Indianapolis, IN, USA
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Rahman S, Engleman EA, Bell RL. Nicotinic receptor modulation to treat alcohol and drug dependence. Front Neurosci 2015. [DOI: https://doi.org/10.3389/fnins.2014.00426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Gubner NR, McKinnon CS, Phillips TJ. Effects of varenicline on ethanol-induced conditioned place preference, locomotor stimulation, and sensitization. Alcohol Clin Exp Res 2014; 38:3033-42. [PMID: 25581658 PMCID: PMC4293040 DOI: 10.1111/acer.12588] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 09/23/2014] [Indexed: 11/30/2022]
Abstract
BACKGROUND Varenicline, a partial nicotinic acetylcholine receptor (nAChR) agonist, is a promising new drug for the treatment of alcohol (ethanol [EtOH]) dependence. Varenicline has been approved by the Food and Drug Administration as a smoking cessation therapeutic and has also been found to reduce EtOH consumption in humans and animal models of alcohol use. These studies examined the hypotheses that varenicline attenuates the stimulant and sensitizing effects of EtOH and reduces the motivational effects of EtOH-associated cues. The goal was to determine whether these effects of varenicline contribute to its pharmacotherapeutic effects for alcohol dependence. In addition, effects of varenicline on acute stimulation and/or on the acquisition of sensitization would suggest a role for nAChR involvement in these effects of EtOH. METHODS Dose-dependent effects of varenicline on the expression of EtOH-induced conditioned place preference (CPP), locomotor activation, and behavioral sensitization were examined. These measures model motivational effects of EtOH-associated cues, euphoric or stimulatory effects of EtOH, and EtOH-induced neuroadaptation. All studies used DBA/2J mice, an inbred strain with high sensitivity to these EtOH-related effects. RESULTS Varenicline did not significantly attenuate the expression of EtOH-induced CPP. Varenicline reduced locomotor activity and had the most pronounced effect in the presence of EtOH, with the largest effect on acute EtOH-induced locomotor stimulation and a trend for varenicline to attenuate the expression of EtOH-induced sensitization. CONCLUSIONS Because varenicline did not attenuate the expression of EtOH-induced CPP, it may not be effective at reducing the motivational effects of EtOH-associated cues. This outcome suggests that reductions in the motivational effects of EtOH-associated cues may not be involved in how varenicline reduces EtOH consumption. However, varenicline did have effects on locomotor behavior and significantly attenuated acute EtOH-induced locomotor stimulation. In humans who drink while taking varenicline, it might similarly reduce stimulant responses and have an impact on continued drinking. General sedative effects in such individuals should be carefully considered.
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Affiliation(s)
- Noah R. Gubner
- Department of Behavioral Neuroscience and Portland Alcohol Research Center,
Oregon Health & Science University, Portland, OR, USA
| | - Carrie S. McKinnon
- Department of Behavioral Neuroscience and Portland Alcohol Research Center,
Oregon Health & Science University, Portland, OR, USA
| | - Tamara J. Phillips
- Department of Behavioral Neuroscience and Portland Alcohol Research Center,
Oregon Health & Science University, Portland, OR, USA
- VA Medical Center, Portland, OR, USA
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Holtyn AF, Kaminski BJ, Wand GS, Weerts EM. Differences in extinction of cue-maintained conditioned responses associated with self-administration: alcohol versus a nonalcoholic reinforcer. Alcohol Clin Exp Res 2014; 38:2639-46. [PMID: 25336025 DOI: 10.1111/acer.12537] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 07/30/2014] [Indexed: 11/27/2022]
Abstract
BACKGROUND Stimuli paired with alcohol may evoke conditioned responses that influence consumption and relapse. Understanding extinction of conditioned responses for both alcohol and nonalcoholic reinforcers, and their relation to subsequent consumption, may be useful in identifying methods to maintain abstinence. METHODS Nine baboons self-administered alcohol (n = 4) or a nonalcoholic reinforcer (orange-flavored Tang(®) , n = 5) under a 3-component chained schedule of reinforcement (CSR). Each component was associated with distinct stimuli and response requirements, which modeled periods of anticipation (Component 1), seeking (Component 2), and consumption (Component 3). No behavioral contingencies were in effect during Component 1. Responses in Component 2, required to gain access to Component 3, provided indices of seeking behavior. Alcohol or Tang® was available only in Component 3. Initial conditions parametrically manipulated the concentration of alcohol (2 to 6% w/v) or Tang (25 to 100%) that was available for self-administration. The breaking point (BP) of alcohol- and Tang-seeking responses at each of the concentrations was determined by adding a progressive ratio schedule to Component 2. Extinction of responding under stimulus conditions identical to those during baseline, but with no access to alcohol or Tang, was examined using across- and within-session extinction procedures. RESULTS The BP for 2% w/v alcohol was lower than that for 4 and 6%, which were closely similar. For Tang, BPs increased as the concentration increased. When concentrations of alcohol and Tang were adjusted to produce comparable BPs, self-administration of Tang was higher when compared to alcohol; however, alcohol-related cues maintained higher BPs than Tang-related cues when only water was available for self-administration. Alcohol seeking and self-administration responses were more resistant to extinction than those for Tang. CONCLUSIONS Stimuli paired with alcohol or nonalcoholic reinforcers will gain different motivational properties. Alcohol-related stimuli produced persistent responding that was highly resistant to change, highlighting the role of environmental stimuli in compulsive drinking and relapse.
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Affiliation(s)
- August F Holtyn
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
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