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Jiménez JC, Cortés-Salazar F, Ruiz-García RI, Hernández D, Miranda F. The effects of intra-accumbal administration of the nicotinic acetylcholine receptor agonist cytisine on the operant oral self-administration of ethanol were prevented by the GABAB receptor agonist baclofen in rats. Pharmacol Biochem Behav 2024; 244:173850. [PMID: 39159761 DOI: 10.1016/j.pbb.2024.173850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2024] [Revised: 08/10/2024] [Accepted: 08/13/2024] [Indexed: 08/21/2024]
Abstract
RATIONALE Although the mesocorticolimbic dopamine (DA) system is the main neurochemical substrate that regulates the addictive and reinforcing effects of ethanol (EtOH), other neurotransmitter systems, such as the acetylcholine (Ach) system, modulate DAergic function in the nucleus accumbens (nAcc). Previously, we reported that intra-nAcc administration of the nicotinic Ach receptor agonist cytisine increased oral EtOH self-administration. GABAB receptors in the nAcc are expressed in DAergic terminals, inhibit the regulation of DA release into the nAcc, and could modulate the effects of cytisine on oral EtOH self-administration. The present study assessed the effects of intra-nAcc administration of the GABAB receptor agonist baclofen (BCF) on the impacts of cytisine on oral EtOH self-administration. METHODS Male Wistar rats were deprived of water for 23.30 h and then trained to press a lever to receive EtOH on an FR3 schedule until a stable response rate of 80 % was achieved. After this training, the rats received an intra-nAcc injection of the nAch receptor agonist cytisine, BCF, and cytisine or 2-hydroxysaclofen, BCF, and cytisine before they were given access to EtOH on an FR3 schedule. RESULTS Intra-nAcc injections of cytisine increased oral EtOH self-administration; this effect was reduced by BCF, and 2-hydroxysaclofen blocked the effects of BCF. CONCLUSIONS These findings suggest that the reinforcing effects of EtOH are modulated not only by the DA system but also by other neurotransmitter systems involved in regulating DA release from DAergic terminals.
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Affiliation(s)
- Juan C Jiménez
- Universidad Nacional Autónoma de México, Facultad de Estudios Superiores Iztacala, Mexico
| | - Felipe Cortés-Salazar
- Universidad Nacional Autónoma de México, Facultad de Estudios Superiores Iztacala, Mexico
| | - Rosa I Ruiz-García
- Universidad Nacional Autónoma de México, Facultad de Estudios Superiores Iztacala, Mexico
| | - David Hernández
- Departamento de Psiquiatría y Salud Mental, Facultad de Medicina, Universidad de Concepción, Concepción, Chile
| | - Florencio Miranda
- Universidad Nacional Autónoma de México, Facultad de Estudios Superiores Iztacala, Mexico.
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Quintanilla ME, Rivera-Meza M, Berríos-Cárcamo P, Cassels BK. Reduction of nicotine and ethanol intake in alcohol-preferring (UChB) female rats by the α4β2 nicotinic acetylcholine receptor partial agonists 5-bromocytisine and cytisine. Drug Alcohol Depend 2023; 250:110900. [PMID: 37515828 DOI: 10.1016/j.drugalcdep.2023.110900] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 06/25/2023] [Accepted: 07/11/2023] [Indexed: 07/31/2023]
Abstract
RATIONALE Neuronal nicotinic acetylcholine receptors (nAChRs) are implicated in the reinforcing effects of nicotine and ethanol. Previous studies have shown that cytisine and its 5-bromo derivative are partial agonists at the α4β2 nAChRs and that the parent molecule cytisine is effective in reducing both nicotine- and ethanol-self-administration in rats. However, whether 5-bromocytisine affects nicotine or ethanol self-administration was unknown. OBJECTIVES The present study compared the effects of 5-bromocytisine and cytisine on nicotine self-administration and further assessed the effect of daily drug injection on voluntary ethanol consumption in alcohol-preferring female rats. Animals were administered a 1.5mg/kg i.p. dose of 5-bromocytisine or cytisine every day for 15-16 days. RESULTS The initial efficacy of 5-bromocytisine and cytisine in reducing nicotine intake was similar (-80%) while for voluntary ethanol intake 5-bromocytisine was a superior inhibitor over cytisine (-78% and -40% respectively). The efficacy of cytisine began to diminish after 10 days of daily administration, which was attributed to tolerance development to its inhibitory effects both on nicotine and ethanol self-administration. Tolerance did not develop for 5-bromocytisine. CONCLUSION 5-Bromocytisine, a weaker α4β2 nAChR partial agonist than cytisine, also produces a sustained inhibition of both nicotine and ethanol self-administration, and unlike cytisine, it does not develop tolerance.
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Affiliation(s)
- María Elena Quintanilla
- Molecular and Clinical Pharmacology Program, Institute of Biomedical Science, Faculty of Medicine, University of Chile, Santiago, Chile.
| | - Mario Rivera-Meza
- Department of Pharmacological and Toxicological Chemistry, Faculty of Chemical and Pharmaceutical Sciences, University of Chile, Santiago, Chile.
| | - Pablo Berríos-Cárcamo
- Center for Regenerative Medicine, Faculty of Medicine Clínica Alemana-Universidad del Desarrollo, Santiago 7710162, Chile.
| | - Bruce K Cassels
- Department of Chemistry, Faculty of Sciences, University of Chile, Santiago 7800003, Chile.
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3
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Cytisine and cytisine derivatives. More than smoking cessation aids. Pharmacol Res 2021; 170:105700. [PMID: 34087351 DOI: 10.1016/j.phrs.2021.105700] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 05/29/2021] [Accepted: 05/29/2021] [Indexed: 12/12/2022]
Abstract
Cytisine, a natural bioactive compound that is mainly isolated from plants of the Leguminosae family (especially the seeds of Laburnum anagyroides), has been marketed in central and eastern Europe as an aid in the clinical management of smoking cessation for more than 50 years. Its main targets are neuronal nicotinic acetylcholine receptors (nAChRs), and pre-clinical studies have shown that its interactions with various nAChR subtypes located in different areas of the central and peripheral nervous systems are neuroprotective, have a wide range of biological effects on nicotine and alcohol addiction, regulate mood, food intake and motor activity, and influence the autonomic and cardiovascular systems. Its relatively rigid conformation makes it an attractive template for research of new derivatives. Recent studies of structurally modified cytisine have led to the development of new compounds and for some of them the biological activities are mediated by still unidentified targets other than nAChRs, whose mechanisms of action are still being investigated. The aim of this review is to describe and discuss: 1) the most recent pre-clinical results obtained with cytisine in the fields of neurological and non-neurological diseases; 2) the effects and possible mechanisms of action of the most recent cytisine derivatives; and 3) the main areas warranting further research.
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4
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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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Tutka P, Vinnikov D, Courtney RJ, Benowitz NL. Cytisine for nicotine addiction treatment: a review of pharmacology, therapeutics and an update of clinical trial evidence for smoking cessation. Addiction 2019; 114:1951-1969. [PMID: 31240783 DOI: 10.1111/add.14721] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 01/08/2019] [Accepted: 06/18/2019] [Indexed: 01/30/2023]
Abstract
AIMS To review cytisine's history of use, pre-clinical evidence, clinical pharmacokinetics, efficacy, adverse reactions (ARs) and safety for smoking cessation. METHODS A synoptic review of the use of cytisine as a smoking cessation medication, mechanism of action, pharmacokinetics and safety. Relevant literature on data included in these sections were identified through a search of 11 databases with additional literature obtained from reports and monographs. Three databases (PubMed, EMBASE and www.elibrary.ru) were systematically searched for studies published from 2012 to August 2018 in any language to provide an updated meta-analysis of cytisine's efficacy and ARs for smoking cessation compared with placebo. We pooled the relative risks (RR) of abstinence in the efficacy analysis and RR of ARs, either reported by the authors or calculated from the reports. RESULTS Cytisine has been in use since 1964 and is currently marketed in 18 countries. Systemic bioavailability from oral ingestion is high and clearance is primarily renal, with minimal or no metabolism. Brain uptake in animal models is moderate. The plasma half-life averages 4.8 hours. Eight studies were included for meta-analysis of efficacy. With heterogeneous results, the overall RR versus placebo of successful continuous abstinence at the longest follow-up was 1.74 [95% confidence interval (CI) = 1.38-2.19]. Nausea, vomiting, dyspepsia, upper abdominal pain and dry mouth that were mild or moderate were the most common ARs, with RR versus placebo 1.10 (95% CI = 0.95-1.28). The cost of cytisine in eastern and central Europe is several-fold less than that of other smoking cessation medications. CONCLUSIONS Cytisine is a low-cost medication found to increase the likelihood of smoking cessation. The most frequently reported ARs of cytisine involve gastrointestinal symptoms that are mostly reported as either mild or moderate in severity.
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Affiliation(s)
- Piotr Tutka
- Department of Experimental and Clinical Pharmacology, University of Rzeszów, Rzeszów, Poland.,Laboratory for Innovative Research in Pharmacology, University of Rzeszów, Rzeszów, Poland.,National Drug and Alcohol Research Centre, University of New South Wales, Sydney, NSW, Australia
| | - Denis Vinnikov
- School of Public Health, Al-Farabi Kazakh National University, Almaty, Kazakhstan.,Biological Institute, National Research Tomsk State University, Tomsk, Russia
| | - Ryan J Courtney
- National Drug and Alcohol Research Centre, University of New South Wales, Sydney, NSW, Australia
| | - Neal L Benowitz
- Division of Clinical Pharmacology and Experimental Therapeutics, Department of Medicine, University of California San Francisco, San Francisco, CA, USA.,Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
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6
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González-Gutiérrez JP, Pessoa-Mahana HA, Iturriaga-Vásquez PE, Reyes-Parada MI, Guerra-Díaz NE, Hodar-Salazar M, Viscarra F, Paillali P, Núñez-Vivanco G, Lorca-Carvajal MA, Mella-Raipán J, Zúñiga MC. Synthesis of Novel Nicotinic Ligands with Multimodal Action: Targeting Acetylcholine α4β2, Dopamine and Serotonin Transporters. Molecules 2019; 24:molecules24203808. [PMID: 31652614 PMCID: PMC6832503 DOI: 10.3390/molecules24203808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/07/2019] [Accepted: 10/20/2019] [Indexed: 11/16/2022] Open
Abstract
Nicotinic acetylcholine receptors (nAChRs), serotonin transporters (SERT) and dopamine transporters (DAT) represent targets for the development of novel nicotinic derivatives acting as multiligands associated with different health conditions, such as depressive, anxiety and addiction disorders. In the present work, a series of functionalized esters structurally related to acetylcholine and nicotine were synthesized and pharmacologically assayed with respect to these targets. The synthesized compounds were studied in radioligand binding assays at α4β2 nAChR, h-SERT and h-DAT. SERT experiments showed not radioligand [3H]-paroxetine displacement, but rather an increase in the radioligand binding percentage at the central binding site was observed. Compound 20 showed Ki values of 1.008 ± 0.230 μM for h-DAT and 0.031 ± 0.006 μM for α4β2 nAChR, and [3H]-paroxetine binding of 191.50% in h-SERT displacement studies, being the only compound displaying triple affinity. Compound 21 displayed Ki values of 0.113 ± 0.037 μM for α4β2 nAChR and 0.075 ± 0.009 μM for h-DAT acting as a dual ligand. Molecular docking studies on homology models of α4β2 nAChR, h-DAT and h-SERT suggested potential interactions among the compounds and agonist binding site at the α4/β2 subunit interfaces of α4β2 nAChR, central binding site of h-DAT and allosteric modulator effect in h-SERT.
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Affiliation(s)
- Juan Pablo González-Gutiérrez
- Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 8380492 Santiago, Chile.
| | - Hernán Armando Pessoa-Mahana
- Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 8380492 Santiago, Chile.
| | - Patricio Ernesto Iturriaga-Vásquez
- Departamento de Ciencias Químicas y Recursos Naturales, Facultad de Ingeniería y Ciencias, Universidad de la Frontera, 4811230 Temuco, Chile.
- Center of Excellence in Biotechnology Research Applied to the Environment, Universidad de La Frontera, 4811230 Temuco, Chile.
| | - Miguel Iván Reyes-Parada
- Centro de Investigación Biomédica y Aplicada (CIBAP), Escuela de Medicina, Facultad de Ciencias Médicas, Universidad de Santiago de Chile, 9170022 Santiago, Chile.
- Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, 3467987 Sede Talca, Chile.
| | - Nicolas Esteban Guerra-Díaz
- Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 8380492 Santiago, Chile.
| | - Martin Hodar-Salazar
- Departamento de Ciencias Químicas y Recursos Naturales, Facultad de Ingeniería y Ciencias, Universidad de la Frontera, 4811230 Temuco, Chile.
| | - Franco Viscarra
- Departamento de Ciencias Químicas y Recursos Naturales, Facultad de Ingeniería y Ciencias, Universidad de la Frontera, 4811230 Temuco, Chile.
| | - Pablo Paillali
- Departamento de Ciencias Químicas y Recursos Naturales, Facultad de Ingeniería y Ciencias, Universidad de la Frontera, 4811230 Temuco, Chile.
| | - Gabriel Núñez-Vivanco
- Centro de Bioinformática y Simulación Molecular, Universidad de Talca, 3340000 Talca, Chile.
- Escuela de Ingeniería Civil en Bioinformática, Universidad de Talca, Av. Lircay 3340000 Talca, Chile.
| | | | - Jaime Mella-Raipán
- Instituto de Química y Bioquímica, Facultad de Ciencias, Universidad de Valparaíso, 2360102 Valparaíso, Chile.
| | - María Carolina Zúñiga
- Departamento de Química Inorgánica and Analítica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 8380492 Santiago, Chile.
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7
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Trigo JM, Le Foll B. Nicotine Self-Administration as Paradigm for Medication Discovery for Smoking Cessation: Recent Findings in Medications Targeting the Cholinergic System. Methods Mol Biol 2019; 2011:165-193. [PMID: 31273700 DOI: 10.1007/978-1-4939-9554-7_11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Tobacco kills every year approximately six million people as a direct result of direct use, and it is still considered one of the most excruciating threats for human health worldwide. The low successful rates of the currently available pharmacotherapies to assist in quitting tobacco use suggest there is a need for more effective treatments.The intravenous self-administration (IVSA) paradigm is considered the gold standard to study voluntary drug intake in animal models, including nicotine. The IVSA paradigm has been used to identify key mechanisms involved in the addictive properties of nicotine in both rodents and nonhuman primates. In this chapter we describe how the IVSA paradigm has served to further investigate the role of nicotinic acetylcholine receptors (nAChRs) in the reinforcing properties of nicotine. Notably, this review will cover recent advances (i.e., research carried out during the past decade) using the IVSA paradigm, with a focus on the status of research on current smoking cessation medications (such as varenicline and bupropion) and of other nAChR ligands.The combination of the IVSA paradigm with pharmacological and genetic tools (e.g., knockout animals) has greatly contributed to our understanding of the role of specific subtype nAChRs in nicotine reinforcement processes. We also discuss some of the limitations of the IVSA paradigm so these can be taken into consideration when interpreting and designing new studies.
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Affiliation(s)
- Jose M Trigo
- Translational Addiction Research Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada
| | - Bernard Le Foll
- Translational Addiction Research Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada.
- Addictions Division, CAMH, Toronto, ON, Canada.
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8
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Shao XM, Liu S, Lee ES, Fung D, Pei H, Liang J, Mudgway R, Zhang J, Feldman JL, Zhu Y, Louie S, Xie XS. Chronic intermittent nicotine delivery via lung alveolar region-targeted aerosol technology produces circadian pharmacokinetics in rats resembling human smokers. J Appl Physiol (1985) 2018; 125:1555-1562. [PMID: 30236046 PMCID: PMC6295479 DOI: 10.1152/japplphysiol.00357.2018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 09/18/2018] [Accepted: 09/20/2018] [Indexed: 11/22/2022] Open
Abstract
Cigarette smoke is an aerosol containing microparticles that carry nicotine into the lung alveolar region where nicotine is rapidly absorbed into circulation. Nicotine exposure in smokers is a chronic intermittent process, with episodic intake during wakefulness and abstinence during sleep resulting in circadian fluctuation of blood nicotine levels. We developed an integrated platform where freely moving rodents can be exposed to episodic nicotine aerosol on an investigator-designed schedule. Plasma nicotine and its metabolite cotinine levels were determined with a LC-MS/MS method. We characterized the aerosol in the breathing zone of the rodent exposure chamber. The droplet-size distribution was within the respirable diameter range. The system can generate a wide range of nicotine concentrations in air that meet a variety of experimental needs. Rats were exposed to nicotine aerosol once every half hour in the dark phase of 12:12-h light-dark cycles for 10 days. We optimized the parameters of aerosol generation and exposure: plasma nicotine and cotinine concentrations reached 30-35 and 190-240 ng/ml, respectively. The nicotine levels and circadian patterns resembled the pharmacokinetic pattern of human smokers. In summary, we developed an aerosol system that can produce clinically relevant chronic intermittent nicotine exposure in unanesthetized, unrestrained rodents with route of administration and circadian blood pharmacokinetics resembling human smokers. This methodology is a novel tool for understanding the health effects of chronic intermittent nicotine exposure such as with tobacco cigarettes and electronic cigarettes for studies of behavior, pharmacology and toxicology, nicotine addiction, tobacco-related diseases, and teratogenicity, and for the discovery of therapeutics. NEW & NOTEWORTHY We developed a lung alveolar region-targeted aerosol method and a system that provides chronic intermittent nicotine exposure in freely moving rodents. The method produces in rodents clinically relevant nicotine exposure with the route and circadian pharmacokinetics resembling human smokers. This method is a novel tool for understanding the health impacts of chronic nicotine exposures such as with tobacco cigarettes and electronic cigarettes, for studying nicotine pharmacology, toxicology, addiction, and tobacco-related diseases, and for the discovery of therapeutics.
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Affiliation(s)
- Xuesi M Shao
- Department of Neurobiology, David Geffen School of Medicine at UCLA , Los Angeles, California
| | - Siyu Liu
- Titus Family Department of Clinical Pharmacy, University of Southern California School of Pharmacy , Los Angeles, California
| | - Eon S Lee
- Department of Environmental Health Sciences, UCLA Fielding School of Public Health , Los Angeles, California
| | - David Fung
- Department of Environmental Health Sciences, UCLA Fielding School of Public Health , Los Angeles, California
| | - Hua Pei
- Titus Family Department of Clinical Pharmacy, University of Southern California School of Pharmacy , Los Angeles, California
| | - Jing Liang
- Titus Family Department of Clinical Pharmacy, University of Southern California School of Pharmacy , Los Angeles, California
| | - Ross Mudgway
- Department of Neurobiology, David Geffen School of Medicine at UCLA , Los Angeles, California
| | - Jingxi Zhang
- AfaSci Research Laboratories, AfaSci, Incorporated, Redwood City, California
| | - Jack L Feldman
- Department of Neurobiology, David Geffen School of Medicine at UCLA , Los Angeles, California
| | - Yifang Zhu
- Department of Environmental Health Sciences, UCLA Fielding School of Public Health , Los Angeles, California
| | - Stan Louie
- Titus Family Department of Clinical Pharmacy, University of Southern California School of Pharmacy , Los Angeles, California
| | - Xinmin S Xie
- AfaSci Research Laboratories, AfaSci, Incorporated, Redwood City, California
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Abstract
INTRODUCTION Tobacco use causes one premature death every six seconds. Current smoking cessation aids include nicotine replacement therapies, bupropion, and varenicline. Although more than 70% of smokers express a desire to quit, fewer than 3% remain abstinent for more than one year, highlighting a critical need for more efficacious smoking cessation treatments. Areas covered: The authors discuss the rationale, preclinical and clinical development of varenicline for smoking cessation. They cover the development of varenicline as a partial agonist at α4β2 receptors, the primary neural substrate for nicotine reward. Then, they discuss evidence from preclinical studies indicating varenicline's efficacy in blocking nicotine reward, followed by clinical trials demonstrating safety and efficacy in sustaining abstinence in smokers. Finally, they cover post-market surveillance, including caution in heavy machine operators, putative cardiovascular risk, and the repealed warning for adverse neuropsychiatric events. Expert opinion: Varenicline development was based on strong theoretical rationale and preclinical evidence. Clinical studies indicate that varenicline is safe and more effective in sustaining abstinence than placebo, bupropion or nicotine replacement therapies. However, given that continuous abstinence rates across studies remain low (18 ~ 30% with varenicline; 4 ~ 10% with placebo), novel and more effective medications targeting other nicotinic or glutamate receptors for smoking cessation are required.
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Affiliation(s)
- Chloe J. Jordan
- Molecular Targets and Medications Discovery Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA
| | - Zheng-Xiong Xi
- Molecular Targets and Medications Discovery Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA
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Wall TR, Henderson BJ, Voren G, Wageman CR, Deshpande P, Cohen BN, Grady SR, Marks MJ, Yohannes D, Kenny PJ, Bencherif M, Lester HA. TC299423, a Novel Agonist for Nicotinic Acetylcholine Receptors. Front Pharmacol 2017; 8:641. [PMID: 29033834 PMCID: PMC5626944 DOI: 10.3389/fphar.2017.00641] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2017] [Accepted: 08/29/2017] [Indexed: 01/11/2023] Open
Abstract
(E)-5-(Pyrimidin-5-yl)-1,2,3,4,7,8-hexahydroazocine (TC299423) is a novel agonist for nicotinic acetylcholine receptors (nAChRs). We examined its efficacy, affinity, and potency for α6β2∗ (α6β2-containing), α4β2∗, and α3β4∗ nAChRs, using [125I]-epibatidine binding, whole-cell patch-clamp recordings, synaptosomal 86Rb+ efflux, [3H]-dopamine release, and [3H]-acetylcholine release. TC299423 displayed an EC50 of 30–60 nM for α6β2∗ nAChRs in patch-clamp recordings and [3H]-dopamine release assays. Its potency for α6β2∗ in these assays was 2.5-fold greater than that for α4β2∗, and much greater than that for α3β4∗-mediated [3H]-acetylcholine release. We observed no major off-target binding on 70 diverse molecular targets. TC299423 was bioavailable after intraperitoneal or oral administration. Locomotor assays, measured with gain-of-function, mutant α6 (α6L9′S) nAChR mice, show that TC299423 elicits α6β2∗ nAChR-mediated responses at low doses. Conditioned place preference assays show that low-dose TC299423 also produces significant reward in α6L9′S mice, and modest reward in WT mice, through a mechanism that probably involves α6(non-α4)β2∗ nAChRs. However, TC299423 did not suppress nicotine self-administration in rats, indicating that it did not block nicotine reinforcement in the dosage range that was tested. In a hot-plate test, TC299423 evoked antinociceptive responses in mice similar to those of nicotine. TC299423 and nicotine similarly inhibited mouse marble burying as a measure of anxiolytic effects. Taken together, our data suggest that TC299423 will be a useful small-molecule agonist for future in vitro and in vivo studies of nAChR function and physiology.
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Affiliation(s)
- Teagan R Wall
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Brandon J Henderson
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV, United States
| | - George Voren
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Charles R Wageman
- Institute of Behavioral Genetics, University of Colorado, Boulder, Boulder, CO, United States
| | - Purnima Deshpande
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Bruce N Cohen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Sharon R Grady
- Institute of Behavioral Genetics, University of Colorado, Boulder, Boulder, CO, United States
| | - Michael J Marks
- Institute of Behavioral Genetics, University of Colorado, Boulder, Boulder, CO, United States.,Department of Psychology and Neuroscience, University of Colorado, Boulder, Boulder, CO, United States
| | | | - Paul J Kenny
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | | | - Henry A Lester
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
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11
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Anderson GD, Chan LN. Pharmacokinetic Drug Interactions with Tobacco, Cannabinoids and Smoking Cessation Products. Clin Pharmacokinet 2016; 55:1353-1368. [PMID: 27106177 DOI: 10.1007/s40262-016-0400-9] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Tobacco smoke contains a large number of compounds in the form of metals, volatile gases and insoluble particles, as well as nicotine, a highly addictive alkaloid. Marijuana is the most widely used illicit drug of abuse in the world, with a significant increase in the USA due to the increasing number of states that allow medical and recreational use. Of the over 70 phytocannabinoids in marijuana, Δ9-tetrahydrocannabinol (Δ9THC), cannabidiol (CBD) and cannibinol are the three main constituents. Both marijuana and tobacco smoking induce cytochrome P450 (CYP) 1A2 through activation of the aromatic hydrocarbon receptor, and the induction effect between the two products is additive. Smoking cessation is associated with rapid downregulation of CYP1A enzymes. On the basis of the estimated half-life of CYP1A2, dose reduction of CYP1A drugs may be necessary as early as the first few days after smoking cessation to prevent toxicity, especially for drugs with a narrow therapeutic index. Nicotine is a substrate of CYP2A6, which is induced by oestrogen, resulting in lower concentrations of nicotine in females than in males, especially in females taking oral contraceptives. The significant effects of CYP3A4 inducers and inhibitors on the pharmacokinetics of Δ9THC/CBD oromucosal spray suggest that CYP3A4 is the primary enzyme responsible for the metabolism of Δ9THC and CBD. Limited data also suggest that CBD may significantly inhibit CYP2C19. With the increasing use of marijuana and cannabis products, clinical studies are needed in order to determine the effects of other drugs on pharmacokinetics and pharmacodynamics.
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Affiliation(s)
- Gail D Anderson
- Department of Pharmacy, Box 357630, University of Washington, Seattle, WA, 98195, USA.
| | - Lingtak-Neander Chan
- Department of Pharmacy, Box 357630, University of Washington, Seattle, WA, 98195, USA
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Han J, Wang DS, Liu SB, Zhao MG. Cytisine, a Partial Agonist of α4β2 Nicotinic Acetylcholine Receptors, Reduced Unpredictable Chronic Mild Stress-Induced Depression-Like Behaviors. Biomol Ther (Seoul) 2016; 24:291-7. [PMID: 27098858 PMCID: PMC4859792 DOI: 10.4062/biomolther.2015.113] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 09/30/2015] [Accepted: 10/07/2015] [Indexed: 01/05/2023] Open
Abstract
Cytisine (CYT), a partial agonist of α4β2-nicotinic receptors, has been used for antidepressant efficacy in several tests. Nicotinic receptors have been shown to be closely associated with depression. However, little is known about the effects of CYT on the depression. In the present study, a mouse model of depression, the unpredictable chronic mild stress (UCMS), was used to evaluate the activities of CYT. UCMS caused significant depression-like behaviors, as shown by the decrease of total distances in open field test, and the prolonged duration of immobility in tail suspension test and forced swimming test. Treatment with CYT for two weeks notably relieved the depression-like behaviors in the UCMS mice. Next, proteins related to depressive disorder in the brain region of hippocampus and amygdala were analyzed to elucidate the underlying mechanisms of CYT. CYT significantly reversed the decreases of 5-HT1A, BDNF, and mTOR levels in the hippocampus and amygdala. These results imply that CYT may act as a potential anti-depressant in the animals under chronic stress.
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Affiliation(s)
- Jing Han
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi'an 710032, China
| | - Dong-Sheng Wang
- Department of Orthopedics, Jinling Hospital, Clinical School of Nanjing, Second Military Medical University, Nanjing 210002, China
| | - Shui-Bing Liu
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi'an 710032, China
| | - Ming-Gao Zhao
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi'an 710032, China
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