Mechanisms of Nicotine Addiction

The association of maternal smoking around birth with chronic respiratory diseases in adult offspring: A Mendelian randomization study

INTRODUCTION

Maternal smoking during pregnancy disturbs fetal lung development, and induces in their offspring childhood respiratory diseases. Whether it has a continued impact on offspring adult lung health and exerts a casual effect of chronic respiratory diseases (CRDs), remains uncertain. We seek to determine the causal relationships between maternal smoking around birth and offspring adult CRDs, using summary data from previously described cohorts.

METHODS

Mendelian randomization (MR) study was used to analyze the genome-wide associations of maternal smoking around birth and offspring adult CRDs, including respiratory insufficiency, chronic obstructive pulmonary disease (COPD), related respiratory insufficiency, emphysema, COPD, COPD hospital admissions, early onset of COPD, later onset of COPD, asthma, idiopathic pulmonary fibrosis (IPF), lung cancer (LC), small cell lung carcinoma (SCLC), and lung squamous cell carcinoma (LUSC).

RESULTS

After removing single-nucleotide polymorphisms (SNPs) associated with smoking by the offspring, maternal smoking around birth was associated with increased risk of offspring adult respiratory diseases (OR=1.14; 95% CI: 1.013-1.284; p=0.030), respiratory insufficiency (OR=2.413; 95% CI: 1.039-5.603; p=0.040), COPD (OR=1.14; 95% CI: 1.013-1.284; p=0.003), and asthma (OR=1.336; 95% CI: 1.161-1.538; p<0.001). Besides, maternal smoking during pregnancy was associated with a greater risk of LUSC (OR=1.229; 95% CI: 0.992-1.523; p=0.059) than the risk of IPF (OR=1.001; 95% CI: 0.999-1.003; p=0.224), LC (OR=1.203; 95% CI: 0.964-1.501; p=0.103), or SCLC (OR=1.11; 95% CI: 0.77-1.601; p=0.577).

CONCLUSIONS

In this MR analysis, maternal smoking around birth caused a strong risk factor for the offspring to develop lung problems and CRDs in adulthood. The policy related to smoking cessation for mothers during pregnancy should be encouraged.

Nicotine-induced activation of cholinergic receptor nicotinic alpha 5 subunit mediates the malignant behaviours of laryngeal squamous epithelial cells by interacting with RABL6

Nicotine, a crucial constituent of tobacco smoke, can bind to and activate nicotinic acetylcholine receptors (nAChRs), thereby regulating various biological functions. However, the specific mechanisms through which nicotine mediates nAChRs to regulate the metastasis of laryngeal squamous cell carcinoma (LSCC) remain elusive. In this study, smoking status was found to be closely associated with metastasis in patients with LSCC. In addition, nicotine exposure potentiated the hematogenous and lymphatic metastatic capacity of LSCC cells. Nicotine activates membrane-bound CHRNA5, promoting cell migration and invasion, EMT and cell-ECM adhesion in LSCC. Furthermore, this study demonstrated that the Ras superfamily protein RABL6 directly interacted with CHRNA5, which preferentially binds to the RABL6-39-279aa region, and this interaction was enhanced by nicotine. Nicotine-mediated activation of CHRNA5 enhanced its interaction with RABL6, triggering the JAK2/STAT3 signalling pathway and eventually augmenting the metastatic potential of LSCC cells. This study reveals a novel mechanism through which nicotine-mediated CHRNA5-RABL6 interaction promotes the metastasis of LSCC. The findings of this study may help to develop effective strategies for improving the outcome of patients with LSCC in clinical settings.

Nicotine Dependency Levels Among Adult Electronic Cigarette Smokers in Jeddah, Saudi Arabia: An Analytical Cross-Sectional Study

BACKGROUND

Electronic cigarettes (ECs) are a recent method to deliver nicotine with less harmful effects than traditional cigarettes. Studying nicotine dependence in adult EC users is a crucial area, but few measures are available to evaluate nicotine dependence induced by EC. Our study aims to estimate the levels of nicotine dependency among adult EC smokers using a modified Fagerström Test of Nicotine Dependence (e-FTND) in Jeddah, Saudi Arabia, and to identify EC-associated sociodemographic and smoking-related factors affecting nicotine dependency.

METHODS

An analytical cross-sectional study was conducted on adults 18 years of age and older in Jeddah, Saudi Arabia, from December 2023 to March 2024. Data were collected from the participants using a pre-tested structured self-administered questionnaire, and nicotine dependence was assessed using the modified e-FTND. Descriptive statistics such as frequency, mean, and standard deviation were applied. Chi-square was used to assess the association between categorical variables. Ordinal regression was used to predict the nicotine dependency levels with different variables.

RESULTS

A total of 344 participants were included in the study. The mean e-FTND score for EC users was 4.14 ± 2.45. Females had a lower likelihood of experiencing higher dependence compared to males (OR = 0.52, 95% CI: 0.32, 0.85). Using ECs for more than three years was associated with higher odds of increased dependence (OR = 3.18, 95% CI: 1.28, 7.98; p < 0.001). The use of Pod system devices lowered the odds of developing high nicotine dependence (OR = 0.32, 95% CI: 0.13, 0.75; p = 0.01) compared to Iqos device users, while mechanical Mod device users exhibited a trend towards higher dependence, although it was not statistically significant. Nicotine concentration in ECs had a significant impact on the degree of nicotine dependence. Higher concentrations were associated with increased odds of higher dependence (12-18 mg: OR = 3.26, 95% CI: 1.55, 6.91; >18 mg: OR = 4.53, 95% CI: 2.37, 8.75; p < 0.001).

CONCLUSION

Most exclusive EC users in the study developed a moderate nicotine dependence level. The EC device type and nicotine concentration were significant drivers of nicotine dependence. Additionally, the personal characteristics of the users, such as male gender and duration of use, were associated with a higher risk of dependence. An in-depth understanding of the magnitude of nicotine dependence among EC users will enhance the opportunity for tailored health-enhancing interventions and policies.

Loci on chromosome 20 interact with rs16969968 to influence cigarettes per day in European ancestry individuals

BACKGROUND

The understanding of the molecular genetic contributions to smoking is largely limited to the additive effects of individual single nucleotide polymorphisms (SNPs), but the underlying genetic risk is likely to also include dominance, epistatic, and gene-environment interactions.

METHODS

To begin to address this complexity, we attempted to identify genetic interactions between rs16969968, the most replicated SNP associated with smoking quantity, and all SNPs and genes across the genome.

RESULTS

Using the UK Biobank European subsample, we found one SNP, rs1892967, and two genes, PCNA and TMEM230, that showed a significant genome-wide interaction with rs16969968 for log10 CPD and raw CPD, respectively, in a sample of 116 442 individuals who self-reported currently or previously smoking. We extended these analyses to individuals of South Asian descent and meta-analyzed the combined sample of 117 212 individuals of European and South Asian ancestry. We replicated the gene findings in a meta-analysis of five Finnish samples (N=40 140): FinHealth, FINRISK, Finnish Twin Cohort, GeneRISK, and Health-2000-2011.

CONCLUSIONS

To our knowledge, this represents the first reliable epistatic association between single nucleotide polymorphisms for smoking behaviors and provides a novel direction for possible future functional studies related to this interaction. Furthermore, this work demonstrates the feasibility of these analyses by pooling multiple datasets across various ancestries, which may be applied to other top SNPs for smoking and/or other phenotypes.

A cross-trait study of lung cancer and its related respiratory diseases based on large-scale exome sequencing population

Background

Genome-wide association studies (GWASs) explain the genetic susceptibility between diseases and common variants. Nevertheless, with the appearance of large-scale sequencing profiles, we could explore the rare coding variants in disease pathogenesis.

Methods

We estimated the genetic correlation of nine respiratory diseases and lung cancer in the UK Biobank (UKB) by linkage disequilibrium score regression (LDSC). Then, we performed exome-wide association studies at single-variant level and gene-level for lung cancer and lung cancer-related respiratory diseases using the whole-exome sequencing (WES) data of 427,934 European participants. Cross-trait meta-analysis was conducted by association analysis based on subsets (ASSET) to identify the pleiotropic variants, while in-silico functional analysis was performed to explore their function. Causal mediation analysis was used to explore whether these pleiotropic variants lead to lung cancer is mediated by affecting the chronic respiratory diseases.

Results

Five respiratory diseases [emphysema, pneumonia, asthma, chronic obstructive pulmonary disease (COPD), and fibrosis] were genetically correlated with lung cancer. We identified 102 significant independent variants at single-variant levels for lung cancer and five lung cancer-related diseases. 15:78590583:G>A (missense variant in CHRNA5) was shared in lung cancer, emphysema, and COPD. Meanwhile, 14 significant genes and 87 suggestive genes were identified in gene-based association tests, including HSD3B7 (lung cancer), SRSF2 (pneumonia), TNXB (asthma), TERT (fibrosis), MOSPD3 (emphysema). Based on the cross-trait meta-analysis, we detected 145 independent pleiotropic variants. We further identified abundant pathways with significant enrichment effects, demonstrating that these pleiotropic genes were functional. Meanwhile, the proportion of mediation effects of these variants ranged from 6 to 23 (emphysema: 23%; COPD: 20%; pneumonia: 20%; fibrosis: 7%; asthma: 6%) through these five respiratory diseases to the incidence of lung cancer.

Conclusions

The identified shared genetic variants, genes, biological pathways, and potential intermediate causal pathways provide a basis for further exploration of the relationship between lung cancer and respiratory diseases.

Nicotine promotes development of bile duct ligation-induced liver fibrosis by increasing expression of nicotinic acetylcholine receptors in rats

Aim of the study

Liver fibrosis and cigarette smoking seem to be directly linked. Nicotine, as an agonist of nicotinic acetylcholine receptors (nAChRs), induces many downstream signaling pathways. The pathways through which nicotine affects the process of liver fibrosis have not been clarified. The present study aimed to investigate the nicotine-induced effects on fibrosis progression in cholestatic rats.

Material and methods

First, the Wistar rats were subjected to sham or bile duct ligation (BDL) surgery. The rats were treated with low and high doses of nicotine (1 or 10 mg/kg) for three weeks. They were monitored for their body weights before and 21 days after BDL. Also, spleens were weighed to calculate the spleen/body weight ratio. Ductular proliferation and fibrosis were evaluated using hematoxylin and eosin (H&E) as well as Masson's trichrome staining. The mRNA expression of α4nAChR, α7nAChR, and fibrosis gene α-smooth muscle actin (α-SMA) was measured by real-time PCR.

Results

The findings showed that nicotine promotes the development of BDL-induced liver fibrosis. The ratio of spleen/body weight was significantly affected by nicotine exposure. H&E and Masson's trichrome staining showed that the level of liver fibrosis was higher in the cholestatic BDL groups, and this effect was significantly augmented in the nicotine-treated rats. Also, α4nAChR, α7nAChR, and α-SMA expression was observed in the BDL rats and increased following nicotine treatment.

Conclusions

The activation of nAChR triggers biliary proliferation and liver fibrosis. Studying the intracellular mechanism of nicotine and alteration in the expression of nicotinic receptors following nicotine exposure can be useful both in diagnosing nicotine-related diseases and finding new treatment strategies.

Machine learning reveals diverse cell death patterns in lung adenocarcinoma prognosis and therapy

Cancer cell growth, metastasis, and drug resistance pose significant challenges in the management of lung adenocarcinoma (LUAD). However, there is a deficiency in optimal predictive models capable of accurately forecasting patient prognoses and guiding the selection of targeted treatments. Programmed cell death (PCD) pathways play a pivotal role in the development and progression of various cancers, offering potential as prognostic indicators and drug sensitivity markers for LUAD patients. The development and validation of predictive models were conducted by integrating 13 PCD patterns with comprehensive analysis of bulk RNA, single-cell RNA transcriptomics, and pertinent clinicopathological details derived from TCGA-LUAD and six GEO datasets. Utilizing the machine learning algorithms, we identified ten critical differentially expressed genes associated with PCD in LUAD, namely CHEK2, KRT18, RRM2, GAPDH, MMP1, CHRNA5, TMPRSS4, ITGB4, CD79A, and CTLA4. Subsequently, we conducted a programmed cell death index (PCDI) based on these genes across the aforementioned cohorts and integrated this index with relevant clinical features to develop several prognostic nomograms. Furthermore, we observed a significant correlation between the PCDI and immune features in LUAD, including immune cell infiltration and the expression of immune checkpoint molecules. Additionally, we found that patients with a high PCDI score may exhibit resistance to immunotherapy and standard adjuvant chemotherapy regimens; however, they may benefit from other FDA-supported drugs such as docetaxel and dasatinib. In conclusion, the PCDI holds potential as a prognostic signature and can facilitate personalized treatment for LUAD patients.

Technology-based interventions for tobacco smoking prevention and treatment: a 20-year bibliometric analysis (2003-2022)

BACKGROUND

Substance abuse, particularly tobacco smoking, is a significant global public health concern. Efforts have been made to reduce smoking prevalence and promote cessation, but challenges, such as nicotine addiction, marketing tactics by tobacco industry, and cultural acceptability hinder progress. Technology has emerged as a potential tool to address these challenges by providing innovative scalable interventions. The objective of the study was to analyze and map scientific literature on technology-based intervention for tobacco prevention and treatment.

METHODS

A bibliometric methodology was conducted. Scopus database was used to retrieve relevant research articles published between 2003 and 2022. The analysis included publication trends, key contributors, research hotspots, research themes, the most impactful articles, and emerging research topics.

RESULTS

A total of 639 articles were found, with a slow and fluctuating growth pattern observed after 2011. The Journal of Medical Internet Research was the most prominent journal in the field. The United States was the leading country in the field, followed up by the United Kingdom, and the Netherlands. Research hotspots included smoking cessation, randomized controlled trials, and technology-based methods such as internet, mHealth, smartphone apps, text messages, and social media. Four primary research themes were identified: development of smartphone applications, efficacy of text messaging interventions, acceptance and effectiveness of smartphone applications, and interventions targeting young adults and students using mobile phone and social media platforms. The top 10 cited articles demonstrated effectiveness of digital interventions in promoting smoking cessation rates and reducing relapse rates. Emerging research topics included the use of virtual reality interventions, interventions for specific populations through personalized tools, and technology-based interventions in non-Western countries.

CONCLUSIONS

The findings of the current study highlight the potential of technology to address the challenges associated with tobacco smoking. Further future research in this area is warranted to continue advancing the field and developing effective and evidence-based interventions to combat tobacco smoking.

Auxiliary protein and chaperone regulation of neuronal nicotinic receptor subtype expression and function

Neuronal nicotinic acetylcholine receptors (nAChRs) are a family of pentameric, ligand-gated ion channels that are located on the surface of neurons and non-neuronal cells and have multiple physiological and pathophysiological functions. In order to reach the cell surface, many nAChR subtypes require the help of chaperone and/or auxiliary/accessory proteins for their assembly, trafficking, pharmacological modulation, and normal functioning in vivo. The use of powerful genome-wide cDNA screening has led to the identification and characterisation of the molecules and mechanisms that participate in the assembly and trafficking of receptor subtypes, including chaperone and auxiliary or accessory proteins. The aim of this review is to describe the latest findings concerning nAChR chaperones and auxiliary proteins and pharmacological chaperones, and how some of them control receptor biogenesis or regulate channel activation and pharmacology. Some auxiliary proteins are subtype selective, some regulate various subtypes, and some not only modulate nAChRs but also target other receptors and signalling pathways. We also discuss how changes in auxiliary proteins may be involved in nAChR dysfunctions.

Neurobiology of Stress-Induced Nicotine Relapse

Tobacco smoking is the leading cause of preventable death and disease. Although there are some FAD-approved medicines for controlling smoking, the relapse rate remains very high. Among the factors that could induce nicotine relapse, stress might be the most important one. In the last decades, preclinical studies have generated many new findings that lead to a better understanding of stress-induced relapse of nicotine-seeking. Several molecules such as α3β4 nicotinic acetylcholine receptor, α2-adrenergic receptors, cannabinoid receptor 1, trace amine-associated receptor 1, and neuropeptide systems (corticotropin-releasing factor and its receptors, dynorphine and kappa opioid receptor) have been linked to stress-induced nicotine relapse. In this review, we discuss recent advances in the neurobiology, treatment targets, and potential therapeutics of stress-induced nicotine relapse. We also discuss some factors that may influence stress-induced nicotine relapse and that should be considered in future studies. In the final section, a perspective on some research directions is provided. Further investigation on the neurobiology of stress-induced nicotine relapse will shed light on the development of new medicines for controlling smoking and will help us understand the interactions between the stress and reward systems in the brain.

Anti-hyperalgesic and anti-inflammatory effects of 4R-tobacco cembranoid in a mouse model of inflammatory pain

4R is a tobacco cembranoid that binds to and modulates cholinergic receptors and exhibits neuroprotective and anti-inflammatory activity. Given the established function of the cholinergic system in pain and inflammation, we propose that 4R is also analgesic. Here, we tested the hypothesis that systemic 4R treatment decreases pain-related behaviors and peripheral inflammation via modulation of the alpha 7 nicotinic acetylcholine receptors (α7 nAChRs) in a mouse model of inflammatory pain. We elicited inflammation by injecting Complete Freund's Adjuvant (CFA) into the hind paw of male and female mice. We then assessed inflammation-induced hypersensitivity to cold, heat, and tactile stimulation using the Acetone, Hargreaves, and von Frey tests, respectively, before and at different time points (2.5 h - 8d) after a single systemic 4R (or vehicle) administration. We evaluated the contribution of α7 nAChRs 4R-mediated analgesia by pre-treating mice with a selective antagonist of α7 nAChRs followed by 4R (or vehicle) administration prior to behavioral tests. We assessed CFA-induced paw edema and inflammation by measuring paw thickness and quantifying immune cell infiltration in the injected hind paw using hematoxylin and eosin staining. Lastly, we performed immunohistochemical and flow cytometric analyses of paw skin in α7 nAChR-cre::Ai9 mice to measure the expression of α7 nAChRs on immune subsets. Our experiments show that systemic administration of 4R decreases inflammation-induced peripheral hypersensitivity in male and female mice and inflammation-induced paw edema in male but not female mice. Notably, 4R-mediated analgesia and anti-inflammatory effects lasted up to 8d after a single systemic administration on day 1. Pretreatment with an α7 nAChR-selective antagonist prevented 4R-mediated analgesia and anti-inflammatory effects, demonstrating that 4R effects are via modulation of α7 nAChRs. We further show that a subset of immune cells in the hind paw expresses α7 nAChRs. However, the number of α7 nAChR-expressing immune cells is unaltered by CFA or 4R treatment, suggesting that 4R effects are independent of α7 nAChR-expressing immune cells. Together, our findings identify a novel function of the 4R tobacco cembranoid as an analgesic agent in both male and female mice that reduces peripheral inflammation in a sex-dependent manner, further supporting the pharmacological targeting of the cholinergic system for pain treatment.

Targeting the Actions of Muscarinic Receptors on Dopamine Systems: New Strategies for Treating Neuropsychiatric Disorders

Cholinergic regulation of dopamine (DA) signaling has significant implications for numerous disorders, including schizophrenia, substance use disorders, and mood-related disorders. The activity of midbrain DA neurons and DA release patterns in terminal regions are tightly regulated by cholinergic neurons found in both the striatum and the hindbrain. These cholinergic neurons can modulate DA circuitry by activating numerous receptors, including muscarinic acetylcholine receptor (mAChR) subtypes. This review specifically focuses on the complex role of M2, M4, and M5 mAChR subtypes in regulating DA neuron activity and DA release and the potential clinical implications of targeting these mAChR subtypes.

Society for Research on Nicotine and Tobacco as an Outgrowth of the 1988 Surgeon General's Report on Nicotine Addiction: Reflections of the Early Presidents

INTRODUCTION

The Society for Research on Nicotine and Tobacco began in the United States as a scientific organization "to stimulate the generation and dissemination of new knowledge concerning nicotine and tobacco in all its manifestations." Now in its 30th year, the Society is taking on new challenges in tobacco control, nicotine vaping, product regulation, and public policy.

AIMS AND METHODS

This Review describes the formative years of the Society from the perspective of researchers who were in leadership positions during that time, documenting how biobehavioral and clinical research in the first 10 years was a continuation of the scientific mission of the 1988 United States Surgeon General's Report on Nicotine Addiction and summarizing organizational innovations during each president's term of office.

CONCLUSIONS

The Society's promotion of scientific research served as a catalyst for funding, policy, and regulation, setting the stage for its influence and credibility.

IMPLICATIONS

This Commentary provides context and an overview of the scientific research and the organizational innovations that occurred during the early years of the Society for Research on Nicotine and Tobacco using publications and available documentation. The Society was able to thrive because biobehavioral research on nicotine addiction provided the scientific underpinnings for the tobacco control enterprise as a whole. The objective of this Commentary is to describe formative events in the Society's history based on the accomplishments of its early leaders.

Behavioral characterization of early nicotine withdrawal in the mouse: a potential model of acute dependence

BACKGROUND

Clinical and preclinical research have demonstrated that short-term exposure to nicotine during the initial experimentation stage can lead to early manifestation of withdrawal-like signs, indicating the state of "acute dependence". As drug withdrawal is a major factor driving the progression toward regular drug intake, characterizing and understanding the features of early nicotine withdrawal may be important for the prevention and treatment of drug addiction. In this study, we corroborate the previous studies by showing that withdrawal-like signs can be precipitated after short-term nicotine exposure in mice, providing a potential animal model of acute dependence on nicotine.

RESULTS

To model nicotine exposure from light tobacco use during the initial experimentation stage, mice were treated with 0.5 mg/kg (-)-nicotine ditartrate once daily for 3 days. On the following day, the behavioral tests were conducted after implementing spontaneous or mecamylamine-precipitated withdrawal. In the open field test, precipitated nicotine withdrawal reduced locomotor activity and time spent in the center zone. In the elevated plus maze test, the mecamylamine challenge increased the time spent in the closed arm and reduced the number of entries irrespective of nicotine experience. In the examination of the somatic aspect, precipitated nicotine withdrawal enhanced the number of somatic signs. Finally, nicotine withdrawal did not affect cognitive functioning or social behavior in the passive avoidance, spatial object recognition, or social interaction test.

CONCLUSIONS

Collectively, our data demonstrate that early nicotine withdrawal-like signs could be precipitated by the nicotinic antagonist mecamylamine in mice, and that early withdrawal from nicotine primarily causes physical symptoms.

Foods and beverages associated with smoking craving in heated tobacco product and cigarette smokers: A cross-sectional study

INTRODUCTION

Certain foods and beverages are associated with smoking craving. However, only few studies have explored the relationship between food or beverage-related and taste-associated smoking craving. In this study, we aimed to identify the types of foods related to smoking craving in Japanese individuals who smoke cigarettes or heated tobacco products (HTPs).

METHODS

A total of 657 individuals (HTP and cigarette smokers and never smokers) participated in this cross-sectional study. Participants were asked what foods/beverages, tastes, seasonings, cooking methods, and cuisine categories, made them want to smoke and what foods they consumed.

RESULTS

Alcoholic beverages such as beer, coffee, and fat-rich foods were associated with a higher likelihood of smoking craving. Fruits, dairy products such as milk, and sweet and sour tastes, were associated with a lower likelihood of smoking craving. The daily intake of fruit and dairy products was significantly lower in cigarette and HTP smokers than in non-smokers (median fruit intake: non-smokers, 46.4 g/1000 kcal/day; cigarette smokers, 22.2 g/1000 kcal/day; HTP smokers, 31.4 g/1000 kcal/day; p<0.001; median dairy product intake: non-smokers, 76.3 g/day; cigarette smokers, 48.2 g/day; HTP smokers, 57.6 g/day; p<0.001) as assessed using a food frequency questionnaire (BDHQ).

CONCLUSIONS

Specific foods and beverages such as alcohol, fruits, and dairy products are related to smoking craving, and their intake differs according to smoking status.

The effect of CNQX on self-administration: present in nicotine, absent in methamphetamine model

Objective

Addiction is a chronic disease with limited pharmacological options for intervention. Focusing on reducing glutamate levels in the brain seems to be a promising strategy in addiction treatment research. Our research aimed to evaluate the effects of CNQX, an antagonist that targets AMPA and kainate glutamatergic receptors while also exhibiting affinity for the NMDA receptor, especially by modulating its glycine site. We conducted this assessment on the self-administration of nicotine and methamphetamine via intravenous (IV) administration in rats.

Methods

An operant IV self-administration model was used in male Wistar rats. When animals maintained a stable intake of nicotine or methamphetamine, we administered a single injection of CNQX (in the dose of 3 or 6 mg/kg IV) to evaluate its effect on drug intake. Subsequently, the rats were forced to abstain by staying in their home cages for 2 weeks. The period of abstinence was followed by a context-induced relapse-like session before which animals were pretreated with the injection of CNQX (3 or 6 mg/kg IV) to evaluate its effect on drug seeking.

Results

CNQX significantly reduced nicotine intake during the maintenance phase, but no effect was revealed on nicotine seeking after forced abstinence. CNQX did not affect methamphetamine taking or seeking.

Conclusion

The effect of reducing nicotine taking but not seeking could be explained by different involvement of glutamatergic receptors in various stages of nicotine dependence.

Insights into Pharmacological Activities of Nicotine and 6-Hydroxy-L-nicotine, a Bacterial Nicotine Derivative: A Systematic Review

The purported cognitive benefits associated with nicotine and its metabolites in the brain are a matter of debate. In this review, the impact of the pharmacologically active metabolite of a nicotine derivative produced by bacteria named 6-hydroxy-L-nicotine (6HLN) on memory, oxidative stress, and the activity of the cholinergic system in the brain was examined. A search in the PubMed, Science Direct, Web of Science, and Google Scholar databases, limiting entries to those published between 1992 and 2023, was conducted. The search focused specifically on articles about nicotine metabolites, memory, oxidative stress, and cholinergic system activity, as well as enzymes or pathways related to nicotine degradation in bacteria. The preliminary search resulted in 696 articles, and following the application of exclusion criteria, 212 articles were deemed eligible for inclusion. This review focuses on experimental studies supporting nicotine catabolism in bacteria, and the chemical and pharmacological activities of nicotine and its metabolite 6HLN.

Analysis of illicit drugs in purchased and seized electronic cigarette liquids from the United Kingdom 2014-2021

Increasing popularity and known shortfalls in the regulation of electronic cigarettes (ECs) emphasises the urgent need for closer content monitoring and for comprehensible information on their possible health effects. This study investigated components of EC liquids in samples submitted from 2014 to 2021 and discussed the trends driven by legislation changes. Samples originating from prisoners, teenagers and 'test purchases' of commercially available ECs were analysed by gas chromatography-mass spectrometry (GC-MS). For those containing delta-9-tetrahydrocannabinol (THC) and/or cannabidiol (CBD), the content of these components was quantified by liquid chromatography with quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) to show variation of these compounds in EC liquids; 112 EC liquids were included in this study. Nicotine was detected in 87 (78%) of the EC liquids analysed. Twenty-two, including samples from before and after introduction of the UK Psychoactive Substances Act (2016), contained one or more synthetic cannabinoid receptor agonist (SCRA). THC was detected in only 11 samples, whereas a single sample was found to contain CBD only. Six samples contained a mixture of THC and CBD. In all cases where information was available, the THC/CBD content was less than that stated on the product label. The data collected showed great variation in EC liquid content. Therefore, it is important that users are educated regarding risks associated with EC use. Additionally, substances now controlled under both the UK Misuse of Drugs Act and Psychoactive Substances Act were present. These substances each carry a potential risk to health, which is possibly exacerbated if multiple compounds are inhaled concomitantly.

Nicotine neurotoxicity exacerbation following engineered Ag and Cu (50-60 nm) nanoparticles intoxication. Neuroprotection with nanowired delivery of antioxidant compound H-290/51 together with serotonin 5-HT3 receptor antagonist ondansetron

Nicotine abuse is frequent worldwide leading to about 8 millions people die every year due to tobacco related diseases. Military personnel often use nicotine smoking that is about 12.8% higher than civilian populations. Nicotine smoking triggers oxidative stress and are linked to several neurodegenerative diseases such as Alzheimer's disease. Nicotine neurotoxicity induces significant depression and oxidative stress in the brain leading to neurovascular damages and brain pathology. Thus, details of nicotine neurotoxicity and factors influencing them require additional investigations. In this review, effects of engineered nanoparticles from metals Ag and Cu (50-60 nm) on nicotine neurotoxicity are discussed with regard to nicotine smoking. Military personnel often work in the environment where chances of nanoparticles exposure are quite common. In our earlier studies, we have shown that nanoparticles alone induces breakdown of the blood-brain barrier (BBB) and exacerbates brain pathology in animal models. In present investigation, nicotine exposure in with Ag or Cu nanoparticles intoxicated group exacerbated BBB breakdown, induce oxidative stress and aggravate brain pathology. Treatment with nanowired H-290/51 a potent chain-breaking antioxidant together with nanowired ondansetron, a potent 5-HT3 receptor antagonist significantly reduced oxidative stress, BBB breakdown and brain pathology in nicotine exposure associated with Ag or Cu nanoparticles intoxication. The functional significance of this findings and possible mechanisms of nicotine neurotoxicity are discussed based on current literature.

Electronic nicotine delivery systems (ENDS): A convenient means of smoking?

Electronic nicotine delivery systems (ENDS), which are becoming increasingly popular in many parts of the world, have recently become more sophisticated in terms of their more active content and better controlled vaporisation. This review begins by describing how cigarette smoking led to the development of ENDS as a means of combatting nicotine addiction. ENDS are usually categorised as belonging to one of only three main generations, but a fourth has been added in order to differentiate the latest, most powerful, most advanced and innovative that have improved heating efficiency. Descriptions of the principal substances contained in ENDS are followed by considerations concerning the risk of toxicity due to the presence of albeit low concentrations of such a variety of compounds inhaled over a long time, and the increasingly widespread use of ENDS as a means of smoking illicit drugs. We also review the most widely used pharmacotherapeutic approaches to smoking cessation, and recent epidemiological data showing that ENDS can help some people to stop smoking. However, in order to ensure their appropriate regulation, there is a need for higher-quality evidence concerning the health effects and safety of ENDS, and their effectiveness in discouraging tobacco smoking.

Unhealthy Dietary Patterns and Their Associations with Sociodemographic Factors as Predictors among Underweight and Overweight Adolescents in Southern Thailand

(1) Background: Adolescence is a critical developmental phase; dietary intake and nutritional status significantly impact health outcomes. (2) Objective: This cross-sectional study investigated dietary patterns (DPs) and the association between sociodemographic factors and unhealthy DPs among adolescents in Thailand. (3) Methods: A multi-stage sampling selected 1480 participants from three public high schools in Nakhon Si Thammarat province. A food frequency questionnaire assessed dietary habits, and principal component analysis was used to identify DPs. Multinomial logistic regression examined the association between sociodemographic factors and DPs. (4) Results: The findings show that 25.9% of adolescents were underweight, 14.7% were overweight, and 5.8% were obese. Three DPs were identified: a healthy 'protein and vegetables' pattern and two unhealthy patterns: 'snacks' and 'processed foods', which explained 12.49%, 10.37%, and 7.07% of the dietary variance, respectively. Among underweight adolescents, higher snack consumption was associated with being younger (odds ratio (OR) = 3.24) and receiving a higher daily allowance (OR = 3.43). Additionally, female adolescents who engaged in frequent exercise had a 2.15 times higher intake of processed foods. Among overweight adolescents, higher snack intake was linked to being younger (OR = 8.65) and having larger families (OR = 6.37). Moreover, an increased daily allowance was associated with higher consumption of processed foods (OR = 11.47). (5) Conclusion: This study underscores the socio-demographic influence on unhealthy DPs. Insights can guide targeted interventions to foster healthier dietary habits during adolescence.

New medications development for smoking cessation

Diseases associated with nicotine dependence in the form of habitual tobacco use are a major cause of premature death in the United States. The majority of tobacco smokers will relapse within the first month of attempted abstinence. Smoking cessation agents increase the likelihood that smokers can achieve long-term abstinence. Nevertheless, currently available smoking cessation agents have limited utility and fail to prevent relapse in the majority of smokers. Pharmacotherapy is therefore an effective strategy to aid smoking cessation efforts but considerable risk of relapse persists even when the most efficacious medications currently available are used. The past decade has seen major breakthroughs in our understanding of the molecular, cellular, and systems-level actions of nicotine in the brain that contribute to the development and maintenance of habitual tobacco use. In parallel, large-scale human genetics studies have revealed allelic variants that influence vulnerability to tobacco use disorder. These advances have revealed targets for the development of novel smoking cessation agents. Here, we summarize current efforts to develop smoking cessation therapeutics and highlight opportunities for future efforts.

Implementing Core Genes and an Omnigenic Model for Behaviour Traits Prediction in Genomics

A high number of genome variants are associated with complex traits, mainly due to genome-wide association studies (GWAS). Using polygenic risk scores (PRSs) is a widely accepted method for calculating an individual's complex trait prognosis using such data. Unlike monogenic traits, the practical implementation of complex traits by applying this method still falls behind. Calculating PRSs from all GWAS data has limited practical usability in behaviour traits due to statistical noise and the small effect size from a high number of genome variants involved. From a behaviour traits perspective, complex traits are explored using the concept of core genes from an omnigenic model, aiming to employ a simplified calculation version. Simplification may reduce the accuracy compared to a complete PRS encompassing all trait-associated variants. Integrating genome data with datasets from various disciplines, such as IT and psychology, could lead to better complex trait prediction. This review elucidates the significance of clear biological pathways in understanding behaviour traits. Specifically, it highlights the essential role of genes related to hormones, enzymes, and neurotransmitters as robust core genes in shaping these traits. Significant variations in core genes are prominently observed in behaviour traits such as stress response, impulsivity, and substance use.

Pharmacological strategies for appetite modulation in eating disorders: a narrative review

BACKGROUND

A substantial increase in the prevalence of eating disorders has been noticed over the past decades. Priority in the treatment of eating disorders is justifiably given to psychosocial interventions. However, it is also well known that centrally acting drugs can significantly affect appetite and food consumption.

AIM

To narratively review the available neurobiological data on the mechanisms of central regulation of eating behavior as a rationale to summarize pharmacological strategies for appetite modulation in eating disorders.

METHODS

The authors have carried out a narrative review of scientific papers published from January 2013 to March 2023 in the PubMed and Web of Science electronic databases. Studies were considered eligible if they included data on the neurobiological mechanisms of appetite regulation or the results of clinical trials of centrally acting drugs in eating disorders. Relevant studies were included regardless of their design. Descriptive analysis was used to summarize the obtained data.

RESULTS

The review included 51 studies. The available neurobiological and clinical data allowed us to identify the following pharmacological strategies for appetite modulation in eating disorders: serotonergic, catecholaminergic, amino acidergic and peptidergic. However, implementation of these data into clinical practice difficult due to an insufficient number of good-quality studies, which is particularly relevant for adolescents as there is a research gap in this population.

CONCLUSION

The progress in neurobiological understanding of the mechanisms of central regulation of appetite opens opportunities for new pharmacotherapeutic approaches aimed at changing the patterns of eating behavior. Obviously, treatment of eating disorders is a much broader problem and cannot be reduced to the correction of eating patterns. Nevertheless, at certain stages of treatment, drug-induced modulation of appetite can play an important role among multi-targeted biological and psychosocial interventions. Translation of neurobiological data into clinical practice requires a large number of clinical studies to confirm the long-term efficacy and safety of pharmacotherapeutic approaches and to develop personalized algorithms for the treatment of various forms of eating disorders in different age groups.

Bupropion Mediated Effects on Depression, Attention Deficit Hyperactivity Disorder, and Smoking Cessation

Bupropion had been in use since the late 1980s as an unconventional treatment for depression. Unlike other antidepressants, bupropion has no serotonergic activity and inhibits the reuptake of norepinephrine and dopamine. The drug has been used to treat depression, Attention Deficit Hyperactivity Disorder (ADHD), and smoking cessation. This investigation reviews the pharmacokinetic and pharmacodynamic effects of bupropion and its mechanisms of action and interactions with other drugs. We evaluated the efficacy of major on and off-label uses of bupropion, focusing on the indications, benefits, and adverse effects. Our review demonstrates that bupropion is superior to placebo and non-inferior to SSRIs such as escitalopram in treating major depressive disorder. More research is needed to determine positive patient-centered outcomes such as increases in quality of life. In the case of ADHD, the evidence for efficacy is mixed with poorly conducted randomized clinical trials, small sample sizes, and a lack of long-term assessments. The same is true in the case of bipolar disorder in which there is still limited and controversial data available on bupropion's safety and efficacy. In the case of smoking cessation, bupropion is found to be an effective anti-smoking drug with synergistic benefits when used as a combination therapy. We conclude that bupropion has the potential to provide benefit for a subset of patients who do not tolerate other typical antidepressants or anti-smoking therapies or for those whose treatment goals align with bupropion's unique side effect profile, such as smokers who wish to quit and lose weight. Additional research is needed to determine the drug's full clinical potential, particularly in the areas of adolescent depression and combination therapy with varenicline or dextromethorphan. Clinicians should use this review to understand the varied uses of the drug and identify the situations and patient populations in which bupropion can lend its greatest benefit.

Rare coding variants in CHRNB2 reduce the likelihood of smoking

Human genetic studies of smoking behavior have been thus far largely limited to common variants. Studying rare coding variants has the potential to identify drug targets. We performed an exome-wide association study of smoking phenotypes in up to 749,459 individuals and discovered a protective association in CHRNB2, encoding the β2 subunit of the α4β2 nicotine acetylcholine receptor. Rare predicted loss-of-function and likely deleterious missense variants in CHRNB2 in aggregate were associated with a 35% decreased odds for smoking heavily (odds ratio (OR) = 0.65, confidence interval (CI) = 0.56-0.76, P = 1.9 × 10^-8). An independent common variant association in the protective direction ( rs2072659 ; OR = 0.96; CI = 0.94-0.98; P = 5.3 × 10^-6) was also evident, suggesting an allelic series. Our findings in humans align with decades-old experimental observations in mice that β2 loss abolishes nicotine-mediated neuronal responses and attenuates nicotine self-administration. Our genetic discovery will inspire future drug designs targeting CHRNB2 in the brain for the treatment of nicotine addiction.

Methoxsalen inhibited the acquisition of nicotine self-administration: attenuation by cotinine replacement in rats

Cigarette smoking remains the leading preventable cause of disease and death. Nicotine is the primary reinforcing ingredient in cigarettes sustaining addiction. Cotinine is the major metabolite of nicotine that produces a myriad of neurobehavioral effects. Cotinine supported self-administration and rats with a history of intravenous self-administration of cotinine exhibited relapse-like drug-seeking behavior, suggesting cotinine may also be reinforcing. To date, a potential contribution of cotinine to nicotine reinforcement remains unknown. Nicotine metabolism is mainly catalyzed by hepatic CYP2B1 enzyme in the rat and methoxsalen is a potent CYP2B1 inhibitor. The study tested the hypothesis that methoxsalen inbibits nicotine metabolism and self-administration, and that cotinine replacement attenuates the inhibitory effects of methoxsalen. Acute methoxsalen decreased plasma cotinine levels and increased nicotine levels following subcutaneous nicotine injection. Repeated methoxsalen reduced the acquisition of nicotine self-administration, leading to fewer nicotine infusions, disruption of lever differentiation, smaller total nicotine intake, and lower plasma cotinine levels. On the other hand, methoxsalen did not alter nicotine self-administration during the maintenance phase despite great reduction of plasma cotinine levels. Cotinine replacement by mixing cotinine with nicotine for self-administration dose-dependently increased plasma cotinine levels, counteracted effects of methoxsalen, and enhanced the acquisition of self-administration. Neither basal nor nicotine-induced locomotor activity was altered by methoxsalen. These results indicate that methoxsalen depressed cotinine formation from nicotine and the acquisition of nicotine self-administration, and that replacement of plasma cotinine attenuated the inhibitory effects of methoxsalen, suggesting that cotinine may contribute to the development of nicotine reinforcement.

Electronic Vaporization of Nicotine Salt or Freebase produces differential effects on metabolism, neuronal activity and behavior in male and female C57BL/6J mice

The use of Electronic Nicotine Delivery Systems (ENDS) is increasing in prevalence and popularity. ENDS are a rapidly evolving technology as devices and e-liquid formulations adapt to policy restrictions and market demand To identify the impacts of nicotine formulation and concentration, we exposed female and male C57BL/6J mice to passive electronic vaporization of different nicotine formulations (freebase or salt) and concentrations (1% or 3%) and measured serum nicotine metabolite levels, brain activity by cFos expression, and anxiety-like and motivated behavior using the novelty suppressed feeding test. We found that the 3% freebase nicotine vapor group displayed significantly higher serum nicotine levels than either 1% or 3% nicotine salt formulations, and female mice displayed higher serum nicotine and cotinine levels compared to males. Central amygdala (CeA) activity was significantly elevated in male mice following nicotine vapor exposure, but the increase was not significantly different between nicotine vapor groups. CeA activity in female mice was unaffected. In contrast increased activity in the ventral tegmental area (VTA) was only observed in female mice exposed to 3% nicotine freebase and specifically in the dopaminergic population. Anxiety-like behavior in female mice was relatively unaffected by nicotine vapor exposure, however male mice displayed increased anxiety-like behavior and reduced motivation to feed after vapor exposure, specifically in the 3% freebase group. These results identify important sex differences in the impact of nicotine formulation and concentration on nicotine metabolism, brain region-specific activity and anxiety-like behavior, which may have significant relevance for different consequences of vaping in men and women.

The involvement of dopamine and D2 receptor-mediated transmission in effects of cotinine in male rats

Previous studies indicated that cotinine, the major metabolite of nicotine, supported intravenous self-administration and exhibited relapse-like drug-seeking behaviors in rats. Subsequent studies started to reveal an important role of the mesolimbic dopamine system in cotinine's effects. Passive administration of cotinine elevated extracellular dopamine levels in the nucleus accumbens (NAC) and the D1 receptor antagonist SCH23390 attenuated cotinine self-administration. The objective of the current study was to further investigate the role of mesolimbic dopamine system in mediating cotinine's effects in male rats. Conventional microdialysis was conducted to examine NAC dopamine changes during active self-administration. Quantitative microdialysis and Western blot were used to determine cotinine-induced neuroadaptations within the NAC. Behavioral pharmacology was performed to investigate potential involvement of D2-like receptors in cotinine self-administration and relapse-like behaviors. NAC extracellular dopamine levels increased during active self-administration of cotinine and nicotine with less robust increase during cotinine self-administration. Repeated subcutaneous injections of cotinine reduced basal extracellular dopamine concentrations without altering dopamine reuptake in the NAC. Chronic self-administration of cotinine led to reduced protein expression of D2 receptors within the core but not shell subregion of the NAC, but did not change either D1 receptors or tyrosine hydroxylase in either subregion. On the other hand, chronic nicotine self-administration had no significant effect on any of these proteins. Systemic administration of eticlopride, a D2-like receptor antagonist attenuated both cotinine self-administration and cue-induced reinstatement of cotinine seeking. These results further support the hypothesis that the mesolimbic dopamine transmission plays a critical role in mediating reinforcing effects of cotinine.

Effects of exercise of different intensities on withdrawal symptoms among people with substance use disorder: a systematic review and meta-analysis

Background: Exercise can effectively attenuate withdrawal symptoms and reduce relapse, but it is unknown whether exercise of different intensities produces different results. This study aimed to systematically review the effects of different exercise intensities on withdrawal symptoms among people with substance use disorder (SUD). Methods: Systematic searches for randomized controlled trials (RCTs) on exercise, SUD, and abstinence symptoms were conducted via electronic databases, including PubMed, up to June 2022. Study quality was evaluated using the Cochrane Risk of Bias tool (RoB 2.0) for assessment of risk of bias in randomized trials. The meta-analysis was performed by calculating the standard mean difference (SMD) in outcomes of interventions involving light-, moderate-, and high-intensity exercise for each individual study using Review Manager version 5.3 (RevMan 5.3). Results: In total, 22 RCTs (n = 1,537) were included. Overall, exercise interventions had significant effects on withdrawal symptoms, but the effect size varied with exercise intensity and by outcome measure (i.e., for different negative emotions). Light-, moderate-, and high-intensity exercise reduced cravings after the intervention [SMD = -0.71, 95% CI = (-0.90, -0.52)], and there were no statistical differences between the subgroups (p > 0.05). Light-, moderate-, and high-intensity exercise reduced depression after the intervention [light, SMD = -0.33, 95% CI = (-0.57, -0.09); moderate, SMD = -0.64, 95% CI = (-0.85, -0.42); high, SMD = -0.25, 95% CI = (-0.44, -0.05)], with moderate-intensity exercise producing the best effect (p < 0.05). Only light- and moderate-intensity exercise relieved anxiety after the intervention [light, SMD = -0.48, 95% CI = (-0.71, -0.26); moderate, SMD = -0.58, 95% CI = (-0.85, -0.31)]. Only high-intensity exercise worked in alleviating stress [SMD = -1.13, 95% CI = (-2.22, -0.04)]. Both irritability and restlessness could be improved by light- and moderate-intensity exercise [irritability, SMD = -0.74, 95% CI = (-0.98, -0.50); restless, SMD = -0.72, 95% CI = (-0.98, -0.47)], and there were no statistical differences between the subgroups (p > 0.05). Moderate- and high-intensity exercise decreased withdrawal syndrome after the intervention [moderate, SMD = -0.30, 95% CI = (-0.55, -0.05); high, SMD = -1.33, 95% CI = (-1.90, -0.76)], with high-intensity exercise producing the best effects (p < 0.01). Conclusion: Overall, exercise leads to improvements in withdrawal symptoms in individuals with SUD, but these effects vary significantly between the exercise of different intensities and according to the type of withdrawal symptoms. Moderate-intensity exercise has the greatest benefits in improving depression and anxiety; high-intensity exercise has the greatest benefits in improving withdrawal syndrome. Systematic Review Registration: www.crd.york.ac.uk/PROSPERO/, identifier, CRD42022343791.

Measuring vaping-related expectancies in young adults: Psychometric evaluation of the Electronic Nicotine Vaping Outcomes (ENVO) scale

OBJECTIVE

Electronic cigarettes are the most commonly used tobacco products by young adults. Measures of beliefs about outcomes of use (i.e., expectancies) can be helpful in predicting use, as well as informing and evaluating interventions to impact use.

METHODS

We surveyed young adult students (N = 2296, Mean age=20.0, SD=1.8, 64 % female, 34 % White) from a community college, a historically black university, and a state university. Students answered ENDS expectancy items derived from focus groups and expert panel refinement using Delphi methods. Factor Analysis and Item Response Theory (IRT) methods were used to understand relevant factors and identify useful items.

RESULTS

A 5-factor solution [Positive Reinforcement (consists of Stimulation, Sensorimotor, and Taste subthemes, α = .92), Negative Consequences (Health Risks and Stigma, α = .94), Negative Affect Reduction (α = .95), Weight Control (α = .92), and Addiction (α = .87)] fit the data well (CFI=0.95; TLI=0.94; RMSEA=0.05) and was invariant across subgroups. Factors were significantly correlated with relevant vaping measures, including vaping susceptibility and lifetime vaping. Hierarchical linear regression demonstrated factors were significant predictors of lifetime vaping after controlling for demographics, vaping ad exposure, and peer/family vaping. IRT analyses indicated that individual items tended to be related to their underlying constructs (a parameters ranged from 1.26 to 3.18) and covered a relatively wide range of the expectancies continuum (b parameters ranged from -0.72 to 2.47).

CONCLUSIONS

A novel ENDS expectancy measure appears to be a reliable measure for young adults with promising results in the domains of concurrent validity, incremental validity, and IRT characteristics. This tool may be helpful in predicting use and informing future interventions.

IMPLICATIONS

Findings provide support for the future development of computerized adaptive testing of vaping beliefs. Expectancies appear to play a role in vaping similar to smoking and other substance use. Public health messaging should target expectancies to modify young adult vaping behavior.

Acetylcholine promotes chronic stress-induced lung adenocarcinoma progression via α5-nAChR/FHIT pathway

Chronic stress significantly elevates the expression levels of various neurotransmitters in the tumour microenvironment, thereby promoting the cell growth and metastasis of lung adenocarcinoma (LUAD). However, the role of chronic stress in the progression of LUAD remains unclear. In this study, we found that chronic restraint stress increases the levels of the neurotransmitter acetylcholine (ACh), and the α5-nicotinic acetylcholine receptor (α5-nAChR) and decreased fragile histidine triad (FHIT) expression in vivo. Crucially, the increased ACh levels promoted LUAD cell migration and invasion via modulation of the α5-nAChR/DNA methyltransferase 1 (DNMT1)/FHIT axis. In a chronic unpredictable stress (CUMS) mouse model, chronic stress promotes tumour development, accompanied by changes in α5-nAChR, DNMT1, FHIT, and vimentin. Together, these findings reveal a novel chronic stress-mediated LUAD signalling pathway: chronic stress enforces lung adenocarcinoma cell invasion and migration via the ACh/α5-nAChR/FHIT axis, which could be a potential therapeutic target for chronic stress-related LUAD.

Family functioning and nicotine dependence among smoking fathers: a cross-sectional study

BACKGROUND

Nicotine dependence is a significant public health issue, and understanding the factors associated with nicotine dependence in this population is crucial for developing effective interventions. This study examined the association between family functioning and nicotine dependence levels of smoking fathers based on the McMaster model of family functioning (MMFF), providing evidence for future interventions.

METHODS

In this study, we selected fathers of first- to fifth-grade students from 10 pilot elementary schools in Qingdao whose families smoked. We used the Fagerstrom test to assess nicotine dependence and the Family Assessment Device to evaluate family functioning. We performed univariate analysis to compare differences among those with different levels of nicotine dependence, and we used an ordinal logistic regression analysis to investigate the influences related to nicotine dependence.

RESULTS

This study included 874 smokers, with 78.5% having mild nicotine dependence, 11.7% having moderate dependence, and 9.84% having severe dependence. Univariate analysis showed that smokers with severe dependence had lower education levels, higher prevalence of chronic diseases, more frequent alcohol consumption, and poorer family functioning compared to those with mild to moderate dependence. Ordinal logistic regression analysis showed that poorer general functioning scores (OR = 1.087, 95% CI: 1.008-1.173, P = 0.030), poorer behavioral control (OR = 1.124, 95% CI: 1.026-1.232, P = 0.012), more quit attempts, frequent alcohol consumption, and longer smoking duration may be associated with a higher likelihood of developing severe nicotine dependence. The older age of starting smoking and higher education level may be associated with a lower likelihood of developing severe nicotine dependence. However, it is important to note that the cross-sectional nature of this study precludes the determination of causal relationships.

CONCLUSIONS

This study finds that heavy nicotine dependence in smoking fathers is associated with risky behaviors and demographics such as longer smoking duration and frequent alcohol consumption. Targeted smoking cessation interventions are crucial for this group, taking these specific factors into consideration. Family functioning, particularly general functioning and behavioral control, may also be linked to nicotine dependence, indicating the need for further research in this area.

The role of nicotinic receptors in alcohol consumption

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.

Microglia sustain anterior cingulate cortex neuronal hyperactivity in nicotine-induced pain

BACKGROUND

Long-term smoking is a risk factor for chronic pain, and chronic nicotine exposure induces pain-like effects in rodents. The anterior cingulate cortex (ACC) has been demonstrated to be associated with pain and substance abuse. This study aims to investigate whether ACC microglia are altered in response to chronic nicotine exposure and their interaction with ACC neurons and subsequent nicotine-induced allodynia in mice.

METHODS

We utilized a mouse model that was fed nicotine water for 28 days. Brain slices of the ACC were collected for morphological analysis to evaluate the impacts of chronic nicotine on microglia. In vivo calcium imaging and whole-cell patch clamp were used to record the excitability of ACC glutamatergic neurons.

RESULTS

Compared to the vehicle control, the branch endpoints and the length of ACC microglial processes decreased in nicotine-treated mice, coinciding with the hyperactivity of glutamatergic neurons in the ACC. Inhibition of ACC glutamatergic neurons alleviated nicotine-induced allodynia and reduced microglial activation. On the other hand, reactive microglia sustain ACC neuronal excitability in response to chronic nicotine, and pharmacological inhibition of microglia by minocycline or liposome-clodronate reduces nicotine-induced allodynia. The neuron-microglia interaction in chronic nicotine-induced allodynia is mediated by increased expression of neuronal CX3CL1, which activates microglia by acting on CX3CR1 receptors on microglial cells.

CONCLUSION

Together, these findings underlie a critical role of ACC microglia in the maintenance of ACC neuronal hyperactivity and resulting nociceptive hypersensitivity in chronic nicotine-treated mice.

Nicotine addiction and overweight affect intrinsic neural activity and neurotransmitter activity: A fMRI study of interaction effects

BACKGROUND

Nicotine addiction and overweight often co-exist, but the neurobiological mechanism of their co-morbidity remains to be clarified. In this study, we explore how nicotine addiction and overweight affect intrinsic neural activity and neurotransmitter activity.

METHODS

This study included 54 overweight people and 54 age-, sex-, and handedness-matched normal-weight individuals, who were further divided into four groups based on nicotine addiction. We used a two-way factorial design to compare intrinsic neural activity (calculated by the fALFF method) in four groups based on resting-state functional magnetic resonance images (rs-fMRI). Furthermore, the correlation between fALFF values and PET- and SPECT-derived maps to examine specific neurotransmitter system changes underlying nicotine addiction and overweight.

RESULTS

Nicotine addiction and overweight affect intrinsic neural activity by themselves. In combination, they showed antagonistic effects in the interactive brain regions (left insula and right precuneus). Cross-modal correlations displayed that intrinsic neural activity changes in the interactive brain regions were related to the noradrenaline system (NAT).

CONCLUSION

Due to the existence of interaction, nicotine partially restored the changes of spontaneous activity in the interactive brain regions of overweight people. Therefore, when studying one factor alone, the other should be used as a control variable. Besides, this work links the noradrenaline system with intrinsic neural activity in overweight nicotine addicts. By examining the interactions between nicotine addiction and overweight from neuroimaging and molecular perspectives, this study provides some ideas for the treatment of both co-morbidities.

Varenicline serves as the training stimulus in the drug-discriminated goal-tracking task with rats: initial evaluation of potential neuropharmacological processes

Varenicline (Chantix) is an FDA-approved smoking cessation aid that is pharmacologically similar to nicotine, the primary addictive component found within tobacco. In support of this similarity, previous drug discrimination research in rats has reported that the internal or interoceptive stimulus effects of nicotine and varenicline share stimulus elements. Those shared elements appear to be mediated, in part, by overlapping action at alpha4beta2-containing nicotinic acetylcholine receptors (nAChRs). The research supporting this conclusion, however, has only used nicotine, and not varenicline, as the training drug. Accordingly, we used the discriminated goal tracking (DGT) task in which 1 mg/kg varenicline signaled intermittent access to sucrose. On separate intermixed saline days, sucrose was not available. Rats acquired the discrimination as measured by a differential increase in dipper entries (goal tracking) evoked by varenicline. These rats then received a series of tests with several doses of varenicline, nicotine, nornicotine (a metabolite of nicotine and tobacco alkaloid), sazetidine-A (a partial alpha4beta2 agonist), PHA-543613 (an alpha7 agonist), and bupropion (a norepinephrine and dopamine reuptake inhibitor). Control of goal tracking by varenicline was dose-dependent. Nicotine and nornicotine evoked responding comparable to the varenicline training dose indicating full substitution. Sazetidine-A partially substituted for the varenicline stimulus, whereas bupropion and PHA-543613 evoked little to no varenicline-like responding. These findings indicate that varenicline can serve as the training stimulus in the DGT task. Further, stimulus control of varenicline in the DGT task is driven by its partial agonist activity at alpha4beta2-containing nAChRs. The use of this approach could lead to a better understanding of the pharmacological action of varenicline and help guide treatment geared towards tobacco cessation through a more targeted development of novel synthetically designed, subunit-specific pharmacological interventions.

Topping and grafting affect the alkaloid content and gene expression patterns of tobacco (Nicotiana tabacum L.)

In this study, we aimed to determine molecular mechanisms underlying the effects of topping and grafting in tobacco (Nicotiana tabacum L.) by comparing the alkaloid contents and enrichment pathways of differentially expressed genes (DEGs) among plants subjected to different combinations of topping and grafting treatments. Plants of the tobacco variety "Zhongyan 100" and eggplant (Solanum melongena L.) were grafted in four combinations as scions and rootstocks, respectively. The four treatment groups were tobacco with topping, tobacco without topping, topped tobacco grafted onto an eggplant rootstock, and non-topped tobacco grafted onto an eggplant rootstock. Tobacco leaves were collected on the day of topping, at 7 days after topping, and after flue curing, the alkaloid contents of the collected leaves were determined. Leaves of plants subjected to the different treatments were collected for RNA sequencing and screened for DEGs, which were subsequently subjected to functional enrichment analyses. Analyses revealed reductions in the leaf alkaloid contents of tobacco subjected to combined topping and eggplant grafting. Gene annotation indicated that topping influences biological processes such as starch metabolism and stress response, whereas grafting affected the biosynthesis and metabolic pathways of secondary metabolites. Downregulated DEGs between non-topped tobacco and eggplant-grafted topped tobacco and between topped and non-topped tobacco are mainly involved in inositol phosphate metabolic and biosynthetic processes. Downregulated DEGs between different grafting methods (eggplant-grafted non-topped tobacco vs. non-topped tobacco and eggplant-grafted topped tobacco vs. topped tobacco) are mainly involved in sesquiterpene synthase activity and photosynthesis. The findings of this study provide important insights into the molecular mechanisms underlying the effects of topping and grafting on tobacco plants.

ERK signaling is required for nicotine-induced conditional place preference by regulating neuroplasticity genes expression in male mice

Nicotine is an addictive compound that interacts with nicotinic acetylcholine receptors (nAChRs) in the ventral tegmental area (VTA), inducing a release of dopamine in the nucleus accumbens (NAc). When neurons undergo repeated exposure to nicotine, several adaptive changes in neuroplasticity occur. Activation of nAChRs involves numerous intracellular signaling cascades that likely contribute to neuroplasticity and ultimately the establishment of nicotine addiction. Nevertheless, the molecular mechanisms underlying this adaptation remain unclear. To explore the effects of nicotine on neuroplasticity, a stable nicotine-induced conditioned place preference (CPP) model was constructed by intravenous injection in mice. Using a PCR array, we observed significant changes in the expression of synaptic plasticity-related genes in the VTA (16 mRNAs) and NAc (40 mRNAs). When mice were pre-treated with PD98059, an extracellular signal-regulated kinase (ERK) inhibitor, more gene expression changes in the VTA (53 mRNAs) and NAc (60 mRNAs) were found. Moreover, PD98059 pre-treatment blocked the increased p-ERK/ERK and p-CREB/CREB ratios and decreased the expression of synaptic plasticity-related proteins such as SAP102, PSD95, synaptophysin, and BDNF, these changes might contribute to preventing the establishment of nicotine-induced CPP. Furthermore, neurons from the VTA and NAc of nicotine CPP mice had an increased dendritic spine density and complexity of dendritic morphology by Golgi staining. PD98059 also blocked this dynamic. These results demonstrate that repeated exposure to nicotine may remold the expression of neuroplasticity-related genes by activating the ERK signaling pathway in the VTA and NAc, and is related to the establishment of nicotine-induced CPP.

Salivary oxidative stress level among tobacco chewers and smokers: A comparative Study

Tobacco contains various toxic contents which produce oxygen-free radicals that damage oral tissues. Since saliva encounters tobacco, it has antioxidant defense system and also can serve as a biomarker for oral diseases. Thus, the present study aims to evaluate salivary oxidative stress levels among smokers and chewers. Unstimulated saliva from 240 males who visited tobacco cessation clinic for the first time was collected. Standard protocol was followed to collect saliva and assess salivary antioxidant levels from 80 participants with the habit of smoking, smokeless, and both (smoking and smokeless) tobacco users. The collected data were statistically analyzed. The mean salivary superoxide dismutase and malonyldialdehyde levels were significantly high for participants with both habits (P < 0.000). There was a significant high reduction of glutathione peroxidase and catalase in participants with both habits (P < 0.000). Both smoking and smokeless tobacco modify salivary antioxidant activity. The estimation of salivary oxidative stress can serve as a diagnostic and prognostic biomarker for oral tissue damage and dysplasia. Furthermore, they can function as early biomarkers in preventing dysplastic changes in the oral cavity.

Smoking-mediated nicotinic acetylcholine receptors (nAChRs) for predicting outcomes for head and neck squamous cell carcinomas

Background

As a human tumor disease, head and neck squamous cell carcinoma (HNSCC) is associated with a high mortality rate worldwide. Nicotinic acetylcholine receptors (nAChRs) are transmembrane receptor proteins and exert their biological effects following activation by nicotine. We aimed to construct a prognostic signature based on the expression of nAChRs among smokers with HNSCC.

Methods

The transcriptome profile of nAChRs was obtained from The Cancer Genome Atlas (TCGA). Following the integration of survival information, univariate Cox regression and least absolute shrinkage and selection operator (LASSO) analyses were performed to screen the prognosis-related nAChRs and construct a prognostic signature. Kaplan–Meier (KM), receiver operating characteristic (ROC), principal component analysis (PCA), and independent prognostic analysis were utilized to verify the predictive power of the nAChR-associated prognostic signature. The expression of α5 nAChR in clinical samples was verified by quantitative reverse transcriptase PCR.

Results

Subunits α2, α5, α9, and β4 were related to the prognosis. The prognostic signature comprised the expression of subunits α5, α9, and β4. The nAChR-associated signature showed high sensitivity and specificity for prognostic prediction and was an independent factor for overall survival. Based on the clinical variables and expression of nAChRs, a nomogram was constructed for predicting the outcomes of HNSCC patients who were smokers in the clinical settings. In clinical specimens, α5 nAChR showed high expression in HNSCC tissues, especially among smokers.

Conclusions

The nAChR-associated signature constructed in this study may provide a better system for the classification of HNSCC patients and facilitate personalized treatment according to their smoking habits.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-10161-x.

Anesthesiologists and the Other Pandemic: Tobacco Use

Tobacco use will kill a projected 1 billion people in the 21st century in one of the deadliest pandemics in history. Tobacco use disorder is a disease with a natural history, pathophysiology, and effective treatment options. Anesthesiologists can play a unique role in fighting this pandemic, providing both immediate (reduction in perioperative risk) and long-term (reduction in tobacco-related diseases) benefits to their patients who are its victims. Receiving surgery is one of the most powerful stimuli to quit tobacco. Tobacco treatments that combine counseling and pharmacotherapy (e.g., nicotine replacement therapy) can further increase quit rates and reduce risk of morbidity such as pulmonary and wound-related complications. The perioperative setting provides a great opportunity to implement multimodal perianesthesia tobacco treatment, which combines multiple evidence-based tactics to implement the four core components of consistent ascertainment and documentation of tobacco use, advice to quit, access to pharmacotherapy, and referral to counseling resources.

An inhibitory brainstem input to dopamine neurons encodes nicotine aversion

Nicotine stimulates the dopamine (DA) system, which is essential for its rewarding effect. Nicotine is also aversive at high doses; yet, our knowledge about nicotine's dose-dependent effects on DA circuits remains limited. Here, we demonstrate that high doses of nicotine, which induce aversion-related behavior in mice, cause biphasic inhibitory and excitatory responses in VTA DA neurons that can be dissociated by distinct projections to lateral and medial nucleus accumben subregions, respectively. Guided by computational modeling, we performed a pharmacological investigation to establish that inhibitory effects of aversive nicotine involve desensitization of α4β2 and activation of α7 nicotinic acetylcholine receptors. We identify α7-dependent activation of upstream GABA neurons in the laterodorsal tegmentum (LDT) as a key regulator of heterogeneous DA release following aversive nicotine. Finally, inhibition of LDT GABA terminals in VTA prevents nicotine aversion. Together, our findings provide a mechanistic circuit-level understanding of nicotine's dose-dependent effects on reward and aversion.

An integral perspective of canonical cigarette and e-cigarette-related cardiovascular toxicity based on the adverse outcome pathway framework

BACKGROUND

Nowadays, cigarette smoking remains the leading cause of chronic disease and premature death, especially cardiovascular disease. As an emerging tobacco product, e-cigarettes have been advocated as alternatives to canonical cigarettes, and thus may be an aid to promote smoking cessation. However, recent studies indicated that e-cigarettes should not be completely harmless to the cardiovascular system.

AIM OF REVIEW

This review aimed to build up an integral perspective of cigarettes and e-cigarettes-related cardiovascular toxicity.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This review adopted the adverse outcome pathway (AOP) framework as a pivotal tool and aimed to elucidate the association between the molecular initiating events (MIEs) induced by cigarette and e-cigarette exposure to the cardiovascular adverse outcome. Since the excessive generation of reactive oxygen species (ROS) has been widely approved to play a critical role in cigarette smoke-related CVD and may also be involved in e-cigarette-induced toxic effects, the ROS overproduction and subsequent oxidative stress are regarded as essential parts of this framework. As far as we know, this should be the first AOP framework focusing on cigarette and e-cigarette-related cardiovascular toxicity, and we hope our work to be a guide in exploring the biomarkers and novel therapies for cardiovascular injury.

Dry powder inhalation, part 1: ancient history and precursors to modern dry powder inhalers

INTRODUCTION

Inhalation of herbs and other compounds has a long history but habits for medical treatment are intertwined with rituals to obtain hallucinatory effects and pleasurable sensations. Several examples of inhaled herbs, and the diseases they were used for, based on early translations of ancient manuscripts related to inhalation were found to be speculative and inconsistent with each other in literature. They needed to be reconsidered and verified with the original sources of information.

AREAS COVERED

Examples of ancient inhalation and the development of early dry powder inhalers up to and including the first half of the twentieth century. Databases used for literature about historic events, ancient habits, and ancient science, included SmartCat, JSTOR, and ANDAT; various facts were verified via personal communication with historians and custodians of historic manuscripts and artifacts.

EXPERT OPINION

Inhalation does not necessarily require active creation of inhalable aerosols, smokes or fumes. Inhaling 'healthy air' with volatile and gaseous components, or fine aerosols in pine forests, on volcano slopes and at the seaside must be considered as inhalation therapy too. From this viewpoint, inhalation therapy may have been much more common and widespread and have a longer history than is currently known from written evidence.

Alpha5 nicotinic acetylcholine receptor mediated immune escape of lung adenocarcinoma via STAT3/Jab1-PD-L1 signalling

Background

Immunotherapy has proven to be an emerging treatment for non-small-cell lung cancer in recent years. Notably, smokers show higher programmed cell death ligand-1 (PD-L1) expression and better responses to PD-1/PD-L1 inhibitors than nonsmokers. Genome-wide association studies show that the CHRNΑ5 encoding α5-nicotinic acetylcholine receptor (α5-nAChR) is especially relevant to lung cancer and nicotine dependence. Jab1 is a key regulatory factor and promotes the stabilization of PD-L1. Our previous study reported that α5-nAChR mediates lung adenocarcinoma (LUAD) epithelial-mesenchymal transition (EMT) and metastasis via STAT3/Jab1. However, the link between α5-nAChR and PD-L1 is unclear in LUAD.

Methods

We used various bioinformatics databases to analyze the expression of related genes and their correlations. Expression and clinicopathologic significance of α5-nAChR and PD-L1 were detected by immunohistochemistry in a tissue microarray. α5-nAChR regulated LUAD cell immune escape by targeting the STAT3/Jab1-PD-L1 signalling by Western-blotting and ChIP in vitro. We used T cell coculture, flow cytometry, ELISA, CCK8 assay and crystal violet staining to detect the expression of regulatory T cell (Tregs), IFN-γ, IL-2 and the ability of T cell-mediated tumour cell killing respectively. IF assays were performed in both cancer cells and tumour xenograft paraffin sections to analyze the protein expression. The in vivo experiments in mouse model were performed to show the α5-nAChR-mediated immune escape via PD-L1 pathway.

Results

The expression of α5-nAChR was correlated with PD-L1 expression, smoking status and lower survival of LUAD in vivo. In vitro, the expression of α5-nAChR mediated phosphorylated STAT3 (pSTAT3), Jab1 and PD-L1 expression. STAT3 bound to the Jab1 or PD-L1 promoter and mediated PD-L1 expression. Jab1 stabilized PD-L1 expression in LUAD cells. Furthermore, in primary T cell cocultured system, downregulation of α5-nAChR suppressed the function of CD4⁺CD25⁺FOXP3⁺ Tregs, enhanced IFN-γ secretion, and increased T cell-mediated killing of LUAD cells. In the Jurkat T cells and LUAD cells coculture assay, inhibition of α5-nAChR increased IL-2 secretion. In tumour xenograft tissues, α5-nAChR expression was related to PD-L1, Jab1, pSTAT3, CD4 and granzyme B expression (GB).

Conclusions

Our results suggest that the novel α5-nAChR/STAT3-Jab1-PD-L1 axis is involved in LUAD immune escape, which could lead to potential therapeutic strategies for cancer immunotherapy.

Role of hemoglobin alpha and hemoglobin beta in non-small-cell lung cancer based on bioinformatics analysis

The differentially expressed genes (DEGs) were identified and screened differentially in non-small-cell lung cancer (NSCLC) using information from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus databases, and the correlation of DEGs in protein interaction, function, and pathway enrichment were analyzed to search for new biomarkers and potential therapeutic targets for NSCLC. Protein-protein interaction network (PPI) analysis showed that CDK1 and GNGT1 were the most significantly upregulated hub nodes, while FPR2 was the most significantly downregulated. Gene Ontology enrichment analysis showed that upregulated DEGs were significantly enriched in protein heterodimerization activity and other functions, while downregulated DEGs were enriched in functions such as heparin-binding. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that upregulation of DEGs were significantly associated with neuroactive ligand-receptor interaction pathways, while downregulation of DEGs were significantly associated with malaria pathways. According to the analysis results, we identified hemoglobin alpha (HBA) and hemoglobin beta (HBB) as the genes of interest for further study. Through tissue level and cell level experiments, we found that the expressions of HBA and HBB in NSCLC tissues were significantly lower than those in paracancerous tissues, and downregulation of HBA and HBB could significantly affect the proliferation ability of NSCLC cells. In addition, we also found that changes in HBA and HBB may affect NSCLC cells through the p38/MAPK pathway and JNK pathway, and ultimately affect the occurrence and development of NSCLC.

Neuroimaging reveals distinct brain glucose metabolism patterns associated with morphine consumption in Lewis and Fischer 344 rat strains

Vulnerability to addiction may be given by the individual's risk of developing an addiction during their lifetime. A challenge in the neurobiology of drug addiction is understanding why some people become addicted to drugs. Here, we used positron emission tomography (PET) and statistical parametric mapping (SPM) to evaluate changes in brain glucose metabolism in response to chronic morphine self-administration (MSA) in two rat strains with different vulnerability to drug abuse, Lewis (LEW) and Fischer 344 (F344). Four groups of animals were trained to self-administer morphine or saline for 15 days. 2-deoxy-2-[¹⁸F]-fluoro-d-glucose (FDG)-PET studies were performed on the last day of MSA (acquisition phase) and after 15 days of withdrawal. PET data were analyzed using SPM12. LEW-animals self-administered more morphine injections per session than F344-animals. We found significant brain metabolic differences between LEW and F344 strains in the cortex, hypothalamus, brainstem, and cerebellum. In addition, the different brain metabolic patterns observed after the MSA study between these rat strains indicate differences in the efficiency of neural substrates to translate the drug effects, which could explain the differences in predisposition to morphine abuse between one individual and another. These findings have important implications for the use of these rat strains in translational morphine and opiate research.

Impact of delivery rate on the acute response to intravenous nicotine: A human laboratory study with implications for regulatory science

Faster delivery rate enhances the abuse potential of drugs of abuse, yet systematic studies on the impact of delivery rate on the acute effects of nicotine in humans are lacking. Using an intravenous (IV) nicotine infusion procedure that allows precise control of rate of delivery, we examined the impact of nicotine delivery rate on the positive subjective drug effects, smoking urges, withdrawal, heart rate, blood pressure and attention function in smokers. Twenty-four male and female (ages 21-35) dependent smokers attended five experimental sessions, following overnight abstinence from smoking. Using a crossover design, participants attended five sessions, where they were assigned to a random sequence of saline infusion or 1 mg nicotine delivered over 1, 2.5, 5 or 10 min at rates of 1, 0.4, 0.2 or 0.1 mg/min, respectively. The positive subjective effects of nicotine were most robust under the two faster delivery rate conditions, 1- and 0.4-mg nicotine/min. In contrast, all nicotine delivery rates were equally more effective than saline in alleviating urges to smoke. Likewise, nicotine-induced heart rate increases did not vary with the rate of nicotine delivery. Lastly, the cognitive enhancing effects of nicotine were observed only under the two slowest delivery rate conditions-0.1- and 0.2-mg nicotine/min. Collectively, these findings support the critical role of delivery rate in optimizing nicotine's abuse potential versus potential therapeutic effects and have timely implications for developing novel therapeutics for nicotine dependence, as well as for tobacco regulatory science.

[Comorbidity of posttraumatic stress disorder and addiction from a biopsychosocial perspective]

Posttraumatic stress disorder and substance use disorder often co-occur within the health care system. Their comorbidity is associated with more serious acute clinical symptomatology, more frequent hospital admissions in state of emergency and significantly lower chances of improvement by psychological and pharmacological treatment. Their comorbidity contributes to dramatically unfavourable courses of illness as regards all biopsychosocial levels. The survey presented will discuss empirical findings from various perspectives: general epidemiology, substance use disorder as risk factor of trauma and PTSD, trauma and PTSD as risk factor of SUD, neurobiological effects of SUD converging towards neurobiology of PTSD, shared common factors of genetics/epigenetics, personality traits, and early developmental stress and trauma. The main focus of analysis will be put on processes that are intrinsically linked to the development and course of both disorders.