Repeated administration of an acetylcholinesterase inhibitor attenuates nicotine taking in rats and smoking behavior in human smokers

Targeting GLP-1 receptors to reduce nicotine use disorder: Preclinical and clinical evidence

Nicotine use disorder (NUD) remains a leading cause of preventable death in the U.S. Unfortunately, current FDA-approved pharmacotherapies for smoking cessation have limited efficacy and are associated with high rates of relapse. One major barrier to long-term smoking abstinence is body weight gain during withdrawal. Nicotine withdrawal-induced body weight gain can also lead to development of chronic disease states like obesity and type II diabetes mellitus. Therefore, it is critical to identify novel pharmacotherapies for NUD that decrease relapse and nicotine withdrawal symptoms including body weight gain. Recent studies demonstrate that glucagon-like peptide-1 receptor (GLP-1R) agonists attenuate voluntary nicotine taking and seeking and prevent withdrawal-induced hyperphagia and body weight gain. Emerging evidence also suggests that GLP-1R agonists improve cognitive deficits, as well as depressive- and anxiety-like behaviors, which contribute to smoking relapse during withdrawal. While further studies are necessary to fully characterize the effects of GLP-1R agonists on NUD and understand the mechanisms by which GLP-1R agonists decrease nicotine withdrawal-mediated behaviors, the current literature supports GLP-1R-based approaches to treating NUD.

Current Pharmacotherapies for Smoking Cessation and Promising Emerging Drugs

OBJECTIVE

Pharmacotherapy is commonly used during quit attempts and has shown an increase in the likelihood of achieving abstinence. However, with established pharmacotherapies, abstinence rates following a quit attempt remain low, and relapse is common. This review aims to investigate the efficacy and harm profiles of current and emerging pharmacotherapies.

METHODS

Literature review of current and emerging pharmacotherapies for smoking cessation and tobacco use disorder.

RESULTS

Emerging pharmacotherapies include new formulations of existing therapies, drug repurposing and some new treatments. New treatments are welcome and may incorporate different mechanisms of action or different safety and tolerability profiles compared to existing treatments. However, emerging pharmacotherapies have yet to demonstrate greater efficacy compared to existing treatments. The emergence of Electronic Nicotine Delivery Systems (ENDS) or 'vaping' is a feature of the current debate around tobacco use disorder. ENDS appear to facilitate switching but not quitting and are controversial as a harm minimisation strategy.

LIMITATIONS

Studies included a broad range of therapies and trial designs that should be compared with their differences taken into consideration.

CONCLUSION

Strategies to successfully quit smoking vary between individuals and may extend beyond pharmacotherapy and involve complex psychosocial factors and pathways.

Cannabinoid receptor GPR55 activation blocks nicotine use disorder by regulation of AMPAR phosphorylation

RATIONALE

Nicotine use disorder can alter synaptic plasticity correlated with learning and memory process. G protein-coupled receptor 55 (GPR55), a novel cannabinoid receptor, which is highly expressed in the central nervous system, plays a prominent role in learning and memory. However, the role of GPR55 in nicotine use disorder remains unclear.

METHODS

In this study, we used the conditioned place preference (CPP) paradigm, a standard and well-established model for evaluating the rewarding effect of drug abuse, to investigate nicotine use disorder behavior in mice. After behavioral tests, the effect of GPR55 on nicotine response was evaluated using Western blotting, immunofluorescence staining, whole-cell patch-clamp recordings, and ELISA.

RESULTS

GPR55 activation significantly reduced nicotine-CPP behavior by decreasing the spontaneous excitatory postsynaptic currents frequency in the nucleus accumbens (NAc) and the release of dopamine in serum. Furthermore, we found that the inhibition effects of nicotine response were mediated by phosphorylation of AMPAR. The PI3K-Akt signaling was involved in nicotine-CPP via GPR55 activation.

CONCLUSION

Our findings showed that GPR55 in the NAc plays a specific role in blocking nicotine-CPP behavior and might be a potential target for the treatment of nicotine use disorder.

Galantamine as a Treatment Option for Nicotine Addiction

The pharmacological therapy for smoking cessation recommended by National Institute for Health and care Excellence (NICE) guidelines is nicotine replacement therapy such as gum, inhalator, lozenge, nasal spray, oral spray, sublingual tablet, and transdermal patch. Medications such as bupropion and varenicline are also used. Varenicline is the only established drug used to alleviate symptoms of craving as it acts as a partial nicotine agonist. Galantamine has a similar mechanism of action where it is an acetylcholinesterase inhibitor and nicotinic receptor agonist. However, varenicline is the only recommended drug. There are not many studies to illustrate the effectiveness of galantamine for smoking cessation. This article explores the possibility of potential use of galantamine in alleviating the symptoms of nicotine withdrawal.

Treating disorders across the lifespan by modulating cholinergic signaling with galantamine

Advances in understanding the regulatory functions of the nervous system have revealed neural cholinergic signaling as a key regulator of cytokine responses and inflammation. Cholinergic drugs, including the centrally acting acetylcholinesterase inhibitor, galantamine, which are in clinical use for the treatment of Alzheimer's disease and other neurodegenerative and neuropsychiatric disorders, have been rediscovered as anti-inflammatory agents. Here, we provide a timely update on this active research and clinical developments. We summarize the involvement of cholinergic mechanisms and inflammation in the pathobiology of Alzheimer's disease, Parkinson's disease, and schizophrenia, and the effectiveness of galantamine treatment. We also highlight recent findings demonstrating the effects of galantamine in preclinical and clinical settings of numerous conditions and diseases across the lifespan that are characterized by immunological, neurological, and metabolic dysfunction.

Erenumab-Induced Severe Nausea Leading to Smoking Cessation: A Retrospective Case Series

OBJECTIVE

Erenumab is a novel treatment modality with a relatively benign and safe side effect profile, currently approved for the prevention of migraine headache. We present 3 cases with chronic migraine who are cigarette smokers were prescribed erenumab, and developed an intense smoking-induced nausea which eventually led to smoking cessation.

METHODS

A multicenter retrospective review of 3 cases with cigarette smoking, one of whom was also smoking marijuana, suffering from chronic migraine resistant to multiple preventive therapies was studied. All were prescribed monthly injections of erenumab 70 mg. Response in terms of headache frequency and intensity and smoking habits was obtained through medical record review.

RESULTS

Out of 3 patients, 2 reported reduced headache frequency and intensity. All patients developed severe nausea while smoking cigarettes after their first dose of erenumab, leading to smoking cessation. One patient co-smoked marijuana, which did not result in nausea after being treated.

CONCLUSION

To the best of our knowledge, this is the first report of severe nausea secondary to erenumab administration and smoking cigarettes, which finally resulted in complete cigarette smoking cessation. As such, further study is indicated on the benefit of erenumab and other calcitonin gene-related peptide antagonists in migraineurs who smoke to promote smoking cessation.

More than Smoke and Patches: The Quest for Pharmacotherapies to Treat Tobacco Use Disorder

Tobacco use is a persistent public health issue. It kills up to half its users and is the cause of nearly 90% of all lung cancers. The main psychoactive component of tobacco is nicotine, primarily responsible for its abuse-related effects. Accordingly, most pharmacotherapies for smoking cessation target nicotinic acetylcholine receptors (nAChRs), nicotine's major site of action in the brain. The goal of the current review is twofold: first, to provide a brief overview of the most commonly used behavioral procedures for evaluating smoking cessation pharmacotherapies and an introduction to pharmacokinetic and pharmacodynamic properties of nicotine important for consideration in the development of new pharmacotherapies; and second, to discuss current and potential future pharmacological interventions aimed at decreasing tobacco use. Attention will focus on the potential for allosteric modulators of nAChRs to offer an improvement over currently approved pharmacotherapies. Additionally, given increasing public concern for the potential health consequences of using electronic nicotine delivery systems, which allow users to inhale aerosolized solutions as an alternative to smoking tobacco, an effort will be made throughout this review to address the implications of this relatively new form of nicotine delivery, specifically as it relates to smoking cessation. SIGNIFICANCE STATEMENT: Despite decades of research that have vastly improved our understanding of nicotine and its effects on the body, only a handful of pharmacotherapies have been successfully developed for use in smoking cessation. Thus, investigation of alternative pharmacological strategies for treating tobacco use disorder remains active; allosteric modulators of nicotinic acetylcholine receptors represent one class of compounds currently under development for this purpose.

Advances in smoking cessation pharmacotherapy: Non-nicotinic approaches in animal models

The landscape of worldwide tobacco use is changing, with a decrease in traditional smoking and an exponential rise in electronic cigarette use. No new nicotine cessation pharmacotherapies have come to market in the last 10 years. The current therapies that have been approved by the United States Food and Drug Administration for nicotine cessation include nicotine replacement therapy, varenicline, a nicotinic acetylcholine receptor partial agonist, and the atypical antidepressant bupropion. Nicotine replacement therapy and varenicline both act on nicotinic acetylcholine receptors. Bupropion inhibits the dopamine transporter, the norepinephrine transporter, and the nicotinic acetylcholine receptors to inhibit smoking behavior. Notwithstanding these treatments, rates of successful nicotine cessation in clinical trials remain low. Recent pharmacological approaches to improve nicotine cessation rates in animal models have turned their focus away from activating nicotinic acetylcholine receptors. The present review focuses on such pharmacological approaches, including nicotine vaccines, anti-nicotine antibodies, nicotine-degrading enzymes, cannabinoids, and metformin. Both immunopharmacological and enzymatic approaches rely on restricting and degrading nicotine within the periphery, thus preventing psychoactive effects of nicotine on the central nervous system. In contrast, pharmacologic inhibition of the enzymes which degrade nicotine could affect smoking behavior. Cannabinoid receptor agonists and antagonists interact with the dopamine reward pathway and show efficacy in reducing nicotine addiction-like behaviors in preclinical studies. Metformin is currently approved by the Food and Drug Administration for the treatment of diabetes. It activates specific intracellular kinases that may protect against the lower metabolism, higher oxidation, and inflammation that are associated with nicotine withdrawal. Further studies are needed to investigate non-nicotinic targets to improve the treatment of tobacco use disorder. This article is part of the special issue on 'Contemporary Advances in Nicotine Neuropharmacology'.

Norditerpenoids with Selective Anti-Cholinesterase Activity from the Roots of Perovskia atriplicifolia Benth

Inhibition of cholinesterases remains one of a few available treatment strategies for neurodegenerative dementias such as Alzheimer’s disease and related conditions. The current study was inspired by previous data on anticholinesterase properties of diterpenoids from Perovskia atriplicifolia and other Lamiaceae species. The acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition by the three new natural compounds—(1R,15R)-1-acetoxycryptotanshinone (1), (1R)-1-acetoxytanshinone IIA (2), and (15R)-1-oxoaegyptinone A (3)—as well as, new for this genus, isograndifoliol (4) were assessed. Three of these compounds exhibited profound inhibition of butyrylcholinesterase (BChE) and much weaker inhibition of acetylcholinesterase (AChE). All compounds (1–4) selectively inhibited BChE (IC₅₀ = 2.4, 7.9, 50.8, and 0.9 µM, respectively), whereas only compounds 3 and 4 moderately inhibited AChE (IC₅₀ 329.8 µM and 342.9 µM). Molecular docking and in silico toxicology prediction studies were also performed on the active compounds. Natural oxygenated norditerpenoids from the traditional Central Asian medicinal plant P. atriplicifolia are selective BChE inhibitors. Their high potential makes them useful candidate molecules for further investigation as lead compounds in the development of a natural drug against dementia caused by neurodegenerative diseases.

Current pharmacologic treatments for smoking cessation and new agents undergoing clinical trials

Smoking causes various diseases and is a major public health threat worldwide. Therefore, promoting smoking cessation is the most important intervention contributing to maintaining the health of smokers and nonsmokers and saving enormous financial expense. We reviewed existing and emerging smoking-cessation pharmacotherapies from the Cochrane Database of Systemic Reviews, PubMed, Ovid, and ClinicalTrials.gov databases. A literature review revealed that bupropion may be appropriate for patients interested in reducing smoking who dislike, or who have failed, nicotine-replacement therapy (NRT). Additionally, varenicline and NRT are efficacious first-line smoking cessation treatments and should be given to all individuals unless contraindicated.

The reviews of this paper are available via the supplementary material section.

Randomized placebo-controlled trial of galantamine in individuals with cocaine use disorder

No pharmacotherapies are approved for the treatment of cocaine use disorder (CUD). Galantamine, a cholinesterase inhibitor, has shown initial promise for cocaine use reduction in methadone-maintained individuals with CUD and cognitive improvement in abstinent individuals with past CUD. However, galantamine has not previously tested in individuals with current CUD and no comorbid opioid use disorder or methadone maintenance. The goal of this 13-week, double-blind, placebo-controlled, randomized controlled trial was to test the efficacy of galantamine (8 mg or 16 mg/day; extended release (ER)) for reducing cocaine use and improving cognitive function in individuals with cocaine use disorder (CUD). Ninety-three treatment-seeking cocaine users were randomized to placebo (n = 32), 8 mg/day galantamine (n = 31) or 16 mg/day galantamine (n = 30). The medication was well-tolerated with minimal reports of side-effects. However, there were no significant treatment group differences in cocaine use outcomes (as measured by self-report or urines). The 16 mg galantamine group had a greater improvement in working memory capacity (Backwards Digit Span), but there were no other significant treatment group differences on key cognitive outcomes. These findings did not provide support for the efficacy of galantamine as a treatment for cocaine use in this sample of individuals with CUD.

Galantamine and Computerized Cognitive Behavioral Therapy for Cocaine Dependence: A Randomized Clinical Trial

OBJECTIVE

To examine whether galantamine, a cognitive-enhancing medication that is both acetylcholinesterase inhibitor and agonist at nicotinic acetylcholine receptors, is effective at improving cocaine use outcomes and cognitive functioning, alone and in combination with computerized cognitive behavioral therapy (CBT).

METHOD

A 12-week, randomized 2 × 2, factorial trial was conducted to evaluate galantamine versus placebo (double-blind) and computerized CBT plus standard methadone treatment versus standard methadone treatment alone in a community-based methadone maintenance program (September 2009-April 2015). One hundred twenty individuals diagnosed with DSM-IV cocaine use disorder were randomly assigned to the following conditions: (1) galantamine (8 mg/d) plus standard methadone maintenance treatment (treatment as usual [TAU]), (2) placebo plus TAU, (3) galantamine plus computerized CBT plus TAU, or (4) placebo plus computerized CBT plus TAU; medication administration was supervised at the time of daily methadone dosing. The primary cocaine use outcome was change in percent days of abstinence over time. Number of cocaine-negative urine toxicology screens submitted and cognitive function were secondary outcomes.

RESULTS

Random effect regression analysis indicated significant reductions in frequency of cocaine use over time, with significant treatment-by-time effects for both galantamine over placebo (F = 5.3, P = .02, d = 0.34) and computerized CBT over standard methadone treatment (F = 4.2, P = .04, d = 0.30) but no evidence of significant benefit of the combination over either treatment alone. Pretreatment to posttreatment comparisons of multiple indices of cognitive functioning, including sustained attention, indicated no benefit of galantamine over placebo.

CONCLUSIONS

Findings suggest benefits of galantamine and computerized CBT for reducing cocaine use in this sample. Although galantamine did not improve measures of cognitive function in this sample, multiple measures of cognitive function were associated with cocaine use outcomes, underlining the significance of cognitive function in cocaine treatment outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00809835.

The Role of Cognitive Control in the Self-Regulation and Reinforcement of Smoking Behavior

Cognitive control (CC)-the ability to regulate attention and memory-plays an important role in a variety of health behaviors, including smoking behavior. In this theoretical review of the literature, we propose a CC and smoking behavior framework that includes (1) the positive influence of CC on the self-regulation of smoking, (2) nicotine-induced improvements in CC that may indirectly reinforce smoking (including withdrawal reversal effects), and (3) the long-term effects of smoking on the brain that may result in reduced CC. Integration of these literatures suggests that CC contributes to both self-regulation (ie, brake pedal) and nicotine-related reinforcement (ie, gas pedal) amid the catastrophic effects of long-term smoking, which may reduce self-regulatory control over smoking while also enhancing indirect reinforcement. Supportive evidence and limitations of this approach will be presented, as well as ideas for future research directions that may fully examine this multifaceted modeling of CC in relation to smoking behavior.

IMPLICATIONS

There is substantial evidence that CC contributes to self-regulation (ie, brake pedal) and reinforcement (ie, gas pedal) of smoking behavior as well as evidence that long-term smoking may cause reduced CC. The proposed model delineates how these opposing influences of CC may mask the unique contribution of self-regulation and reinforcement in maintaining smoking behavior. Targeting CC for treating nicotine dependence will require more nuanced approaches that consider the independent and combined effects of self-regulation and reinforcement to improve smoking cessation success rates.

Neurobiological and Neurophysiological Mechanisms Underlying Nicotine Seeking and Smoking Relapse

Tobacco-related morbidity and mortality continue to be a significant public health concern. Unfortunately, current FDA-approved smoking cessation pharmacotherapies have limited efficacy and are associated with high rates of relapse. Therefore, a better understanding of the neurobiological and neurophysiological mechanisms that promote smoking relapse is needed to develop novel smoking cessation medications. Here, we review preclinical studies focused on identifying the neurotransmitter and neuromodulator systems that mediate nicotine relapse, often modeled in laboratory animals using the reinstatement paradigm, as well as the plasticity-dependent neurophysiological mechanisms that facilitate nicotine reinstatement. Particular emphasis is placed on how these neuroadaptations relate to smoking relapse in humans. We also highlight a number of important gaps in our understanding of the neural mechanisms underlying nicotine reinstatement and critical future directions, which may lead toward the development of novel, target pharmacotherapies for smoking cessation.

Effects of galantamine on smoking behavior and cognitive performance in treatment-seeking smokers prior to a quit attempt

OBJECTIVE

Drugs that enhance cholinergic transmission have demonstrated promise treating addictive disorders. Galantamine, an acetylcholinesterase inhibitor, may reduce cigarette smoking in otherwise healthy treatment-seeking smokers.

METHODS

The current study is a double-blind, placebo-controlled, study that randomized daily smokers (n = 60) to receive one of two doses of galantamine extended release (8 or 16 mg/day), or a placebo treatment. Participants completed a smoking choice task as well as study measures and cognitive tasks in the laboratory and daily life using ecological momentary assessment. Analysis focused on smoking behavior and satisfaction, cognitive performance, and decision to smoke prior to a quit attempt.

RESULTS

Linear mixed models demonstrated that, compared with placebo, both doses of galantamine reduced smoking in a laboratory choice task (p = 0.006) and decreased urine cotinine levels, but not self-reported cigarettes, during the pre-quit period (p = 0.007). Treatment had minimal effect on smoking satisfaction or cognitive performance.

CONCLUSIONS

The results suggest that galantamine reduces nicotine intake but it is unlikely that galantamine improves cognitive performance in otherwise healthy, treatment-seeking smokers. Larger randomized clinical trials can determine if galantamine adjunctive to addiction treatment can improve smoking treatment outcomes.

Current and Emerging Pharmacotherapies for Cessation of Tobacco Smoking

Tobacco use disorder is a chronic illness. With its high comorbidity rate, it is a major cause of years of life lost or years lived with disability; however, it is also considered the most preventable cause of death in developed countries. Since the development of nicotine replacement therapy (NRT) in 1978, treatment options have continued to evolve and expand. Despite this, currently available treatments remain insufficient, with less than 25% of smokers remaining abstinent 1 year after treatment. In this article, we review existing and emerging smoking cessation pharmacotherapies, with a special emphasis on the most promising agents that are currently being investigated. A search of the Cochrane Database of Systematic Reviews and the PubMed, Ovid, and ClinicalTrials.gov databases (August 2 to September 1, 2017) was undertaken for articles on smoking cessation pharmacotherapies, applying no language restrictions. More than 40 pharmacotherapies were reviewed including conventional pharmacotherapies-NRT, bupropion, and varenicline (all approved by the U.S. Food and Drug Administration as first-line treatment of smoking cessation)-and novel therapies: cytisine, N-acetylcysteine, cycloserine, memantine, baclofen, topiramate, galantamine, and bromocriptine. Studies of combination NRT and varenicline showed the greatest smoking cessation rates. Clonidine and nortriptyline are second-line treatments used when first-line treatments fail or are contraindicated, or by patient preference. Some novel therapies, especially acetylcholinesterase inhibitors, cytisine, and N-acetylcysteine, display promising results. Because the results of randomized clinical trials were reported using varied end points and outcome measures, direct comparisons between different pharmacotherapies cannot easily be evaluated. Additional high-quality randomized double-blind placebo-controlled trials with long-term follow-up, using validated sustained abstinence measures, are needed to find more effective smoking cessation aids.

Systematic integration of biomedical knowledge prioritizes drugs for repurposing

The ability to computationally predict whether a compound treats a disease would improve the economy and success rate of drug approval. This study describes Project Rephetio to systematically model drug efficacy based on 755 existing treatments. First, we constructed Hetionet (neo4j.het.io), an integrative network encoding knowledge from millions of biomedical studies. Hetionet v1.0 consists of 47,031 nodes of 11 types and 2,250,197 relationships of 24 types. Data were integrated from 29 public resources to connect compounds, diseases, genes, anatomies, pathways, biological processes, molecular functions, cellular components, pharmacologic classes, side effects, and symptoms. Next, we identified network patterns that distinguish treatments from non-treatments. Then, we predicted the probability of treatment for 209,168 compound-disease pairs (het.io/repurpose). Our predictions validated on two external sets of treatment and provided pharmacological insights on epilepsy, suggesting they will help prioritize drug repurposing candidates. This study was entirely open and received realtime feedback from 40 community members.

Neuropeptide systems and new treatments for nicotine addiction

RATIONALE

The mildly euphoric and cognitive enhancing effects of nicotine play a role in the initiation of smoking, while dysphoria and anxiety associated with smoking cessation contribute to relapse. After the acute withdrawal phase, smoking cues, a few cigarettes (i.e., lapse), and stressors can cause relapse. Human and animal studies have shown that neuropeptides play a critical role in nicotine addiction.

OBJECTIVES

The goal of this paper is to describe the role of neuropeptide systems in the initiation of nicotine intake, nicotine withdrawal, and the reinstatement of extinguished nicotine seeking.

RESULTS

The reviewed studies indicate that several drugs that target neuropeptide systems diminish the rewarding effects of nicotine by preventing the activation of dopaminergic systems. Other peptide-based drugs diminish the hyperactivity of brain stress systems and diminish withdrawal-associated symptom severity. Blockade of hypocretin-1 and nociceptin receptors and stimulation of galanin and neurotensin receptors diminishes the rewarding effects of nicotine. Both corticotropin-releasing factor type 1 and kappa-opioid receptor antagonists diminish dysphoria and anxiety-like behavior associated with nicotine withdrawal and inhibit stress-induced reinstatement of nicotine seeking. Furthermore, blockade of vasopressin 1b receptors diminishes dysphoria during nicotine withdrawal, and melanocortin 4 receptor blockade prevents stress-induced reinstatement of nicotine seeking. The role of neuropeptide systems in nicotine-primed and cue-induced reinstatement is largely unexplored, but there is evidence for a role of hypocretin-1 receptors in cue-induced reinstatement of nicotine seeking.

CONCLUSION

Drugs that target neuropeptide systems might decrease the euphoric effects of smoking and improve relapse rates by diminishing withdrawal symptoms and improving stress resilience.

Attenuation of nicotine taking and seeking in rats by the stoichiometry-selective alpha4beta2 nicotinic acetylcholine receptor positive allosteric modulator NS9283

RATIONALE

The rewarding and reinforcing effects of nicotine are produced, in large part, by activation of neuronal α4β2* nicotinic acetylcholine receptors (nAChRs), pentameric protein complexes comprised of different stoichiometries of α4 and β2 subunits. However, little is known about the functional role of distinct subtypes of α4β2* nAChRs in nicotine addiction.

OBJECTIVES

NS9283 represents a new class of stoichiometry-selective positive allosteric modulators (PAMs) that selectively bind to α4β2 nAChRs containing three α4 and two β2 subunits (3(α4)2(β2) nAChRs). The present experiments were designed to determine the effects of NS9283 on nicotine self-administration and the reinstatement of nicotine-seeking behavior, an animal model of smoking relapse. Parallel studies of sucrose self-administration and reinstatement were conducted in separate cohorts of rats to determine if the effects of NS9283 generalized to other reinforced behaviors.

RESULTS

Acute and repeated administration of NS9283 dose-dependently reduced nicotine self-administration and reinstatement in male Sprague Dawley rats. These effects were reinforcer specific as no effects of NS9283 on sucrose self-administration and reinstatement were noted. NS9283 also failed to substitute for nicotine in supporting self-administration behavior suggesting that, at the doses tested, NS9283 alone is not reinforcing.

CONCLUSION

Taken together, these results provide compelling evidence that stoichiometry-selective PAMs of 3(α4)2(β2) nAChRs attenuate nicotine taking and seeking in rats and suggest that targeting 3(α4)2(β2) nAChRs may represent a promising therapeutic strategy for preventing smoking relapse.

Use of an automated mobile application to assess effects of nicotine withdrawal on verbal fluency: A pilot study

Mild-to-moderate impairment in frontally mediated functions such as sustained attention, working memory, and inhibition have been found to occur during tobacco withdrawal and may present a barrier to successful cessation. These findings have led to studies evaluating cessation treatments that target nicotine withdrawal related cognitive impairment. The instruments currently used to assess cognitive function provide detailed and specific information but have limitations including being time consuming, cumbersome, anxiety provoking, and having poor ecological validity. The authors examined the feasibility of using a mobile computer application to test verbal fluency (VF) as a quick, easy-to-administer, and more ecologically valid method of measuring the effects of short-term smoking abstinence on frontally mediated cognitive functions. Thirty participants completed 2 assessments-1 during ad lib smoking and 1 after overnight abstinence. At each assessment, semantic and phonemic VF tests were administered using a mobile application and nicotine craving and withdrawal symptom severity was assessed. In repeated assessments, performance on both semantic and phonemic VF tests is expected to improve due to practice effects; however, significant improvements were observed only in semantic (p = .012) but not phonemic (p = .154) VF. In addition, the change between assessments in phonemic (but not semantic) score was significantly associated with withdrawal (p = .006) and craving (p = .037) severity measured postabstinence. This study demonstrates that nicotine withdrawal has differential effects on semantic versus phonemic VF suggesting impairments of working memory, attention, and inhibition. These effects were measured using methods easily used in large groups of participants, potentially with remote test administration and automated scoring. (PsycINFO Database Record