Transiently restricting individual amino acids protects Drosophila melanogaster against multiple stressors.

Nutrition and resilience are linked, though it is not yet clear how diet confers stress resistance or the breadth of stressors that it can protect against. We have previously shown that transiently restricting an essential amino acid can protect Drosophila melanogaster against nicotine poisoning. Here, we sought to characterize the nature of this dietary-mediated protection and determine whether it was sex, amino acid and/or nicotine specific. When we compared between sexes, we found that isoleucine deprivation increases female, but not male, nicotine resistance. Surprisingly, we found that this protection afforded to females was not replicated by dietary protein restriction and was instead specific to individual amino acid restriction. To understand whether these beneficial effects of diet were specific to nicotine or were generalizable across stressors, we pre-treated flies with amino acid restriction diets and exposed them to other types of stress. We found that some of the diets that protected against nicotine also protected against oxidative and starvation stress, and improved survival following cold shock. Interestingly, we found that a diet lacking isoleucine was the only diet to protect against all these stressors. These data point to isoleucine as a critical determinant of robustness in the face of environmental challenges.

Determination of Cotinine, 3'-Hydroxycotinine and Nicotine 1'-Oxide in Urine of Passive and Active Young Smokers by LC-Orbitrap-MS/MS Technique.

Tobacco smoke is probably the most significant factor conducing to toxic xenobiotics exposure to humans. The aim of the study was to develop a rapid and sensitive method for the determination of selected nicotine metabolites in urine of tobacco smokers and passive smokers. The method for removing protein and extracting the metabolites involved the centrifugation of urine with acetonitrile. Cotinine, trans-3'-hydroxycotinine, and (2'S)-nicotine 1'-oxide in the supernatant were determined using the LC-Orbitrap-MS/MS technique, with the selected ion monitoring (SIM) and parallel reaction monitoring (PRM) modes used. The recovery of these analytes added to the urine samples ranged from 72% to 101%. Repeatability and reproducibility were less than 3.1% and 10.1%, respectively. The study was carried out among medical students. The group was selected as representatives of young people and who as future physicians should be more aware of the effects of nicotine use. Concentration levels of cotinine and trans-3'-hydroxycotinine determined in ng/mL in the urine of cigarette smokers were 70- and 58-fold higher, respectively, compared to passive smokers. Higher concentrations were recorded in the urine of those passively exposed to tobacco smoke than in non-smokers, confirming that passive exposure to tobacco smoke is not harmless to the human body. However, no significant differences were observed in the concentration of (1'S,2'S)-nicotine 1'-oxide in the samples of individuals from various groups.

Public perceptions and discussions of synthetic nicotine on Twitter.

Background: As alternative replacement products for tobacco-derived nicotine, synthetic nicotine products have recently emerged and gained increasing popularity. This study analyzes public perception and discussion of synthetic nicotine products on Twitter (now "X"). Methods: Through Twitter streaming API (Application Programming Interface), we have collected 2,764 Twitter posts related to synthetic nicotine from December 12, 2021, to October 17, 2022, using keywords related to synthetic nicotine. By applying an inductive approach, two research assistants manually determined the relevance of tweets to synthetic nicotine products and assessed the attitude of tweets as positive, negative, and neutral of tweets toward synthetic nicotine, and the main topics. Results: Among 1,007 tweets related to synthetic nicotine products, the proportion of negative tweets (383/1007, 38.03%) toward synthetic nicotine products was significantly higher than that of positive tweets (218/1007, 21.65%) with a p-value <0.05. Among negative tweets, major topics include the concern about addiction and health risks of synthetic nicotine products (44.91%) and synthetic nicotine as a policy loophole (31.85%). Among positive tweets, top topics include alternative replacement for nicotine (39.91%) and reduced health risks (31.19%). Conclusion: There are mixed attitudes toward synthetic nicotine products on Twitter, resulting from different perspectives. Future research could incorporate demographic information to understand the attitudes of various population groups.

Exploring the association between melatonin and nicotine dependence (Review).

Due to the addictive qualities of tobacco products and the compulsive craving and dependence associated with their use, nicotine dependence continues to be a serious public health concern on a global scale. Despite awareness of the associated health risks, nicotine addiction contributes to numerous acute and chronic medical conditions, including cardiovascular disease, respiratory disorders and cancer. The nocturnal secretion of pineal melatonin, known as the 'hormone of darkness', influences circadian rhythms and is implicated in addiction­related behaviors. Melatonin receptors are found throughout the brain, influencing dopaminergic neurotransmission and potentially attenuating nicotine­seeking behavior. Additionally, the antioxidant properties of melatonin may mitigate oxidative stress from chronic nicotine exposure, reducing cellular damage and lowering the risk of nicotine­related health issues. In addition to its effects on circadian rhythmicity, melatonin acting via specific neural receptors influences sleep and mood, and provides neuroprotection. Disruptions in melatonin signaling may contribute to sleep disturbances and mood disorders, highlighting the potential therapeutic role of melatonin in addiction and psychiatric conditions. Melatonin may influence neurotransmitter systems involved in addiction, such as the dopaminergic, glutamatergic, serotonergic and endogenous opioid systems. Preclinical studies suggest the potential of melatonin in modulating reward processing, attenuating drug­induced hyperactivity and reducing opioid withdrawal symptoms. Chronotherapeutic approaches targeting circadian rhythms and melatonin signaling show promise in smoking cessation interventions. Melatonin supplementation during periods of heightened nicotine cravings may alleviate withdrawal symptoms and reduce the reinforcing effects of nicotine. Further research is required however, to examine the molecular mechanisms underlying the melatonin­nicotine association and the optimization of therapeutic interventions. Challenges include variability in individual responses to melatonin, optimal dosing regimens and identifying biomarkers of treatment response. Understanding these complexities could lead to personalized treatment strategies and improve smoking cessation outcomes.

E-Cigarette Nicotine Delivery Among Young Adults by Nicotine Form, Concentration, and Flavor: A Crossover Randomized Clinical Trial.

Importance: Concerns have been raised about the abuse liability of modern e-cigarettes that use acidic additives to form nicotine salts, making the inhalation of nicotine smoother than freebase nicotine. Objective: To examine the effects of nicotine form and concentration and e-liquid flavor on subjective effects ratings, vaping behavior, and nicotine uptake among young adults who use e-cigarettes. Design, Setting, and Participants: In this single-blind, within-participant, crossover randomized clinical trial, a convenience sample of young adults aged 21 to 25 years who currently used e-cigarettes was recruited from December 2021 to August 2023, for in-person research laboratory visits in Columbus, Ohio. Interventions: Participants completed up to 9 vaping sessions, starting with their usual e-cigarette brand in the first session followed by 1 of 8 laboratory-prepared e-liquids in a randomly assigned order in each subsequent session. Prepared e-liquids varied by nicotine form (salt-based vs freebase), nicotine concentration (5% vs 1% weight per weight), and flavor (menthol vs tobacco). Each session included a 5-minute, 10-puff standardized vaping period followed by 30 minutes of ad libitum vaping. Main Outcomes and Measures: At 4 time points (0, 5, 10, and 35 minutes) during each vaping session, plasma samples were collected for assessing nicotine uptake, and self-reports of urges, craving, and withdrawal were collected via questionnaires. Positive subjective effects were self-reported after 35 minutes of vaping using a visual analog scale; urges and cravings were reported using the Questionnaire of Smoking Urges (QSU). Puff topography data were collected throughout each vaping session. Results: Seventy-two participants (mean [SD] age, 22.4 [1.4] years; 42 [58.3%] female) who sampled at least 1 laboratory-prepared e-liquid composed the analytic sample. Salt-based (vs freebase) nicotine e-liquids increased nicotine intake, with 5% salt-based e-liquids delivering the highest mean plasma levels of nicotine (11.2 ng/mL [95% CI, 9.3-13.2 ng/mL] at 5 minutes; 17.2 ng/mL [95% CI, 14.3-20.1 ng/mL] at 35 minutes) irrespective of flavors. Higher positive subjective effect ratings (eg, for liking) were received by salt-based (42.8; 95% CI, 39.4-46.1) vs freebase (32.0; 95% CI, 28.6-35.3) nicotine, 1% (43.4; 95% CI, 40.2-46.6) vs 5% (31.2; 95% CI, 27.7-34.6) nicotine, and menthol-flavored (43.2; 95% CI, 39.7-46.7) vs tobacco-flavored (31.5; 95% CI, 28.4-34.7) e-liquids. Salt-based and 1% but not menthol-flavored nicotine elicited more intense puffing (eg, 25% [95% CI, 12%-40%] more total puffs for nicotine salts vs freebase). All study e-liquids reduced urges and cravings, with 5% vs 1% nicotine being more effective (mean [SE] QSU-Desire score at 35 minutes, 15.4 [0.5] vs 16.7 [0.5]). Conclusions and Relevance: In this crossover randomized clinical trial among young adult e-cigarette users, salt-based (vs freebase) nicotine e-liquids increased nicotine intake and yielded more positive subjective effects ratings and intense puffing behaviors, suggesting higher abuse potential. Restricting the level of acidic additives and menthol flavoring may reduce the addictiveness of e-cigarettes. Trial Registration: ClinicalTrials.gov Identifier: NCT05458895.

Modeling the population health impact of accurate and inaccurate perceptions of harm from nicotine.

BACKGROUND: Scientific evidence clearly demonstrates that inhaling the smoke from the combustion of cigarettes is responsible for most of the harm caused by smoking, and not the nicotine. However, a majority of U.S. adults who smoke inaccurately believe that nicotine causes cancer which may be a significant barrier, preventing switching to potentially reduced risk, non-combustible products like electronic nicotine delivery systems (ENDS) and smokeless tobacco (ST). We assessed the population health impact associated with nicotine perceptions. METHODS: Using a previously validated agent-based model to the U.S. population, we analyzed nationally representative data from the Population Assessment of Tobacco and Health (PATH) study to estimate base case rates of sustained (maintained over four waves) cessation and switching to non-combustible product use, by sex. Nicotine perception scenarios were determined from PATH data. The overall switch rate from smoking in Wave 4 to non-combustible product use in Wave 5 (3.94%) was stratified based on responses to the nicotine perception question "Do you believe nicotine is the chemical that causes most of the cancer caused by smoking cigarettes?", (four-item scale from "Definitely not" to "Definitely yes"). The relative percent change between the overall and stratified rates, corresponding to each item, was used to adjust the base case rates of switching, to determine the impact, if all adults who smoke exhibited switching behaviors based on responses to the nicotine perceptions question. The public health impact of nicotine perceptions was estimated as the difference in all-cause mortality between the base case and the four nicotine perception scenarios. RESULTS: Switch rates associated with those who responded, "Definitely not" (8.39%) resulted in a net benefit of preventing nearly 800,000 premature deaths over an 85-year period. Conversely switch rates reflective of those who responded, "Definitely yes" (2.59%) resulted in a net harm of nearly 300,000 additional premature deaths over the same period. CONCLUSIONS: Accurate knowledge regarding the role of nicotine is associated with higher switch rates and prevention of premature deaths. Our findings suggest that promoting public education to correct perceptions of harm from nicotine has the potential to benefit public health.

Method Development and Validation of an Aerosol Sampling Technique for the Analysis of Nicotine in Electronic Cigarette Aerosols.

Because of the increasing popularity of e-cigarettes, monitoring the e-cigarette market has become important for national health authorities to guarantee safety and quality. In the EU, the Tobacco Products Directive requires emission studies for e-cigarette products. The absence of industry guidelines for studying these emissions and the lack of proper validation in the literature led us to develop and validate a method using the total error approach for the determination of nicotine in e-cigarette aerosols. A commercial vaping device was used to generate aerosols, which were then collected on Cambridge filter pads and measured for nicotine concentration by UHPLC-DAD after extraction. The method was successfully validated by generating accuracy profiles, which show that the ß-expectation tolerance intervals remained below the acceptance limits of ±20%. Within-run repeatability and intermediate precision were considered acceptable since the highest RSD value obtained was below 5%. The method was applied to 15 commercial e-liquids. A complete validation of a method for the analysis of e-cigarette emissions is presented, including several parameters that impact the accuracy and reproducibility. Similar systematic approaches for method development and validation could be used for other e-cigarette emission analysis methods to ensure the reliability of the measurements.

Nicotine reduces discrimination between threat and safety in the hippocampus, nucleus accumbens and amygdala.

Nicotine intake is linked to the maintenance and development of anxiety disorders and impairs adaptive discrimination of threat and safety in rodents and humans. Yet, it is unclear if nicotine exerts a causal pharmacological effect on the affective and neural mechanisms that underlie aversive learning. We conducted a pre-registered, pseudo-randomly and double-blinded pharmacological fMRI study to investigate the effect of acute nicotine on Fear Acquisition and Extinction in non-smokers (n = 88). Our results show that nicotine administration led to decreased discrimination between threat and safety in subjective fear. Nicotine furthermore decreased differential (threat vs. safety) activation in the hippocampus, which was functionally coupled with Nucleus Accumbens and amygdala, compared to placebo controls. Additionally, nicotine led to enhanced physiological arousal to learned threats and overactivation of the ventral tegmental area. This study provides mechanistic evidence that single doses of nicotine impair neural substrates of adaptive aversive learning in line with the risk for the development of pathological anxiety.

What is the impact of nicotine pouches on oral health: a systematic review.

BACKGROUND: Increase in nicotine pouch (NP) users, particularly among the young, is a matter of concern requiring a comprehensive understanding of its short- and long-term oral health implications. The objective of this research was to systematically review potential oral side-effects associated with NP usage. METHODS: This systematic review was conducted following the PRISMA guidelines. Databases (Medline via PubMed, Scopus, Cochrane Trial, and Google Scholar) were searched for relevant studies up to February 2024. Modified Newcastle-Ottawa Scale (NOS) and the Risk Of Bias In Non-randomized Studies - of Exposure (ROBINS-E) tool were used to assess the quality and bias of the included studies. RESULTS: Three studies were included for this review, two from Europe and one from USA, and considered of a total of 190 participants. All studies were deemed to have a high risk of bias. Participants used NP for periods ranging from 1 month to 10 years. Among these studies, only one study provided information on the usage pattern between 1 and 5 units for an average of 11 ± 7 min per session. Oral mucosal changes at the site of placement were common among NP users. Oral lesions varied from slight wrinkling to various white lesions, seemingly related to the NP units consumed per day and their duration of usage. Other oral side effects included dry mouth, soreness, gingival blisters, and a strange jaw sensation. CONCLUSIONS: Research on the use of NP and its effect on oral health are currently limited. The use of NP should take into consideration the short-and-long-term effects, especially on oral health. Further studies are crucial to understand oral health implications associated with NP usage. SYSTEMATIC REVIEW REGISTRATION: PROSPERO Registration number CRD 42,024,500,711.

Aberrant neural computation of social controllability in nicotine-dependent humans.

Social controllability, or the ability to exert control during social interactions, is crucial for optimal decision-making. Inability to do so might contribute to maladaptive behaviors such as smoking, which often takes place in social settings. Here, we examined social controllability in nicotine-dependent humans as they performed an fMRI task where they could influence the offers made by simulated partners. Computational modeling revealed that smokers under-estimated the influence of their actions and self-reported a reduced sense of control, compared to non-smokers. These findings were replicated in a large independent sample of participants recruited online. Neurally, smokers showed reduced tracking of forward projected choice values in the ventromedial prefrontal cortex, and impaired computation of social prediction errors in the midbrain. These results demonstrate that smokers were less accurate in estimating their personal influence when the social environment calls for control, providing a neurocomputational account for the social cognitive deficits in this population. Pre-registrations: OSF Registries|How interoceptive state interacts with value-based decision-making in addiction (fMRI study). OSF Registries|COVID-19: social cognition, mental health, and social distancing (online study).

Systematic Review of Naturally Derived Substances That Act as Inhibitors of the Nicotine Metabolizing Enzyme Cytochrome P450 2A6.

Tobacco smoking has been highlighted as a major health challenge in modern societies. Despite not causing death directly, smoking has been associated with several health issues, such as cardiovascular diseases, respiratory disorders, and several cancer types. Moreover, exposure to nicotine during pregnancy has been associated with adverse neurological disorders in babies. Nicotine Replacement Therapy (NRT) is the most common strategy employed for smoking cessation, but despite its widespread use, NRT presents with low success and adherence rates. This is attributed partially to the rate of nicotine metabolism by cytochrome P450 2A6 (CYP2A6) in each individual. Nicotine addiction is correlated with the high rate of its metabolism, and thus, novel strategies need to be implemented in NRT protocols. Naturally derived products are a cost-efficient and rich source for potential inhibitors, with the main advantages being their abundance and ease of isolation. This systematic review aims to summarize the natural products that have been identified as CYP2A6 inhibitors, validated through in vitro and/or in vivo assays, and could be implemented as nicotine metabolism inhibitors. The scope is to present the different compounds and highlight their possible implementation in NRT strategies. Additionally, this information would provide valuable insight regarding CYP2A6 inhibitors, that can be utilized in drug development via the use of in silico methodologies and machine-learning models to identify new potential lead compounds for optimization and implementation in NRT regimes.

Flavone attenuates nicotine-induced lung injury in rats exposed to gamma radiation via modulating PI3K/Nrf2 and FoxO1/NLRP3 inflammasome.

Prolonged exposure to different occupational or environmental toxicants triggered oxidative stress and inflammatory reactions mediated lung damage. This study was designed to explore the influence and protective impact of flavone on lung injury in rats intoxicated with nicotine (NIC) and exposed to radiation (IR). Forty rats were divided into four groups; group I control, group II flavone; rats were administered with flavone (25 mg/kg/day), group III NIC + IR; rats were injected intraperitoneally with NIC (1 mg/kg/day) and exposed to γ-IR (3.5 Gy once/week for 2 weeks) while group IV NIC + IR + flavone; rats were injected with NIC, exposed to IR and administered with flavone. Redox status parameters and histopathological changes in lung tissue were evaluated. Nuclear factor-kappa B (NF-κB), forkhead box O-class1 (FoxO1) and nucleotide-binding domain- (NOD-) like receptor pyrin domain-containing-3 (NLRP3) gene expression were measured in lung tissues. Moreover, nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and phosphatidylinositol three kinase (PI3K) were measured using ELISA kits. Our data demonstrates, for the first time, that flavone protects the lung from NIC/IR-associated cytotoxicity, by attenuating the disrupted redox status and aggravating the antioxidant defence mechanism via activation of the PI3K/Nrf2. Moreover, flavone alleviates pulmonary inflammation by inhibiting the inflammatory signaling pathway FOXO1/NF-κB/NLRP3- Inflammasome. Collectively, the obtained results exhibited a notable efficiency of flavone in alleviating lung injury induced by NIC and IR via modulating PI3K/Nrf2 and FoxO1/NLRP3 Inflammasome.

α7-nAChR/P300/NLRP3-regulated pyroptosis mediated poor articular cartilage quality induced by prenatal nicotine exposure in female offspring rats.

Nicotine is developmentally toxic. Prenatal nicotine exposure (PNE) affects the development of multiple fetal organs and causes susceptibility to a variety of diseases in offspring. In this study, we aimed to investigate the effect of PNE on cartilage development and osteoarthritis susceptibility in female offspring rats. Wistar rats were orally gavaged with nicotine on days 9-20 of pregnancy. The articular cartilage was obtained at gestational day (GD) 20 and postnatal week (PW) 24, respectively. Further, the effect of nicotine on chondrogenic differentiation was explored by the chondrogenic differentiation model in human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs). The PNE group showed significantly shallower Safranin O staining and lower Collagen 2a1 content of articular cartilage in female offspring rats. Further, we found that PNE activated pyroptosis in the articular cartilage at GD20 and PW24. In vitro experiments revealed that nicotine inhibited chondrogenic differentiation and activated pyroptosis. After interfering with nod-like receptors3 (NLRP3) expression by SiRNA, it was found that pyroptosis mediated the chondrogenic differentiation inhibition of WJ-MSCs induced by nicotine. In addition, we found that α7-nAChR antagonist α-BTX reversed nicotine-induced NLRP3 and P300 high expression. And, P300 SiRNA reversed the increase of NLRP3 mRNA expression and histone acetylation level in its promoter region induced by nicotine. In conclusion, PNE caused chondrodysplasia and poor articular cartilage quality in female offspring rats. PNE increased the histone acetylation level of NLRP3 promoter region by α7-nAChR/P300, which resulting in the high expression of NLRP3. Further, NLRP3 mediated the inhibition of chondrogenic differentiation by activating pyroptosis.

Procedimento operacional padrão para validação de métodos analíticos para determinação do conteúdo e emissões de produtos do tabaco. Método Oficial TobLabNet da OMS - POP 02

Para estabelecer medidas equivalentes para o ensaio de produtos de tabaco em escala mundial é necessário que haja métodos consensuais de mensuração do conteúdo e das emissões específicas dos cigarros. Nenhum regime de tragada obtido por máquinas é capaz de representar plenamente o comportamento humano de fumar: os ensaios realizados em máquinas de fumar são úteis para caracterizar as emissões de cigarro para fins de design e regulação, mas a divulgação aos fumantes das medições em máquinas pode resultar em interpretações equivocadas a respeito das diferenças de exposição e risco existentes entre as marcas. Os dados de emissão de fumaça obtidos por medições em máquinas podem ser usados como elementos para a avaliação do perigo do produto, mas não são e nem se destinam a ser medidas válidas de exposição ou risco para os seres humanos. A apresentação de diferenças nas medições em máquina como diferenças de exposição ou risco constitui uso indevido dos resultados do ensaio com métodos recomendados da TobLabNet da OMS. Este documento foi preparado por membros da Rede de Laboratórios de Tabaco (TobLabNet) da Organização Mundial da Saúde (OMS) como um procedimento operacional padrão (POP) para a validação de métodos analíticos para determinação do conteúdo em corrente primária e tabaco de cigarro.

Método Oficial TobLabNet da OMS - POP 04. Procedimento operacional padrão para determinação de nicotina em fumo de cigarro

Para estabelecer medidas equivalentes para o ensaio de produtos de tabaco em escala mundial é necessário que haja métodos consensuais de medição do conteúdo e das emissões específicas dos cigarros. Nenhum regime de fumar em máquina é capaz de representar plenamente o comportamento humano de fumar: os ensaios realizados em máquina de fumar são úteis para caracterizar as emissões de cigarro para fins de projeto e regulação, mas a divulgação aos fumantes das medições em máquina pode provocar mal-entendidos a respeito das diferenças de exposição e risco existentes entre as marcas. Os dados de emissão de fumaça obtidos por medições em máquina podem ser usados como elementos para avaliar os perigos do produto, mas não são nem se destinam a ser medidas válidas de exposição ou risco para os seres humanos. A apresentação de diferenças nas medições em máquina como diferenças de exposição ou risco constitui um uso indevido do ensaio de acordo com os padrões da TobLabNet da OMS. Este documento foi preparado por membros da Rede de Laboratórios de Tabaco (TobLabNet) da Organização Mundial da Saúde (OMS) como um procedimento operacional padrão (POP) de método analítico para medição de nicotina em fumo de cigarro.

Procedimento operacional padrão para determinação de nicotina e monóxido de carbono na corrente primária da fumaça do cigarro em condições intensas de tragada. Método Oficial TobLabNet da OMS - POP 10

Para estabelecer medidas equivalentes para o ensaio de produtos de tabaco em escala mundial é necessário que haja métodos consensuais de medição do conteúdo e das emissões específicas dos cigarros. Nenhum regime de tragada obtido por máquinas é capaz de representar plenamente o comportamento humano de fumar: os ensaios realizados em máquinas de fumar são úteis para caracterizar as emissões de cigarro para fins de design e regulação, mas a divulgação aos fumantes das medições em máquinas pode resultar em interpretações equivocadas a respeito das diferenças de exposição e risco existentes entre as marcas. Os dados de emissão de fumaça obtidos por medições em máquinas podem ser usados como elementos para a avaliação do perigo do produto, mas não são e nem se destinam a ser medidas válidas de exposição ou risco para os seres humanos. A apresentação de diferenças nas medições em máquina como diferenças de exposição ou risco constitui uso indevido dos resultados do ensaio com métodos recomendados da TobLabNet da OMS. Este documento foi preparado por membros da Rede de Laboratórios de Tabaco (TobLabNet) da Organização Mundial da Saúde (OMS) como um procedimento operacional padrão (POP) para medição de nicotina e monóxido de carbono na corrente primária do cigarro sob condições intensas de fumada.

Procedimento operacional padrão para determinação de nicotina, glicerol e propilenoglicol em e-líquido. Método Oficial TobLabNet da OMS - POP 11

Para estabelecer medidas equivalentes para o ensaio de e-líquido em escala mundial, é necessário que haja métodos consensuais de medição do conteúdo específico em e-líquido. Como o conteúdo específico de nicotina é limitado a uma determinada concentração em algumas regiões do mundo, por exemplo, na União Europeia, a concen tração máxima de nicotina em e-líquido é de 20 mg/mL, considera-se a nicotina um elemento prioritário a ser medido em e-líquido. O glicerol e o propilenoglicol estão normalmente na composição do e-líquido, estes componentes podem ser medidos com a nicotina. Assim, sua determinação está incluída no POP. Este POP foi preparado para descrever o procedimento para a determinação de nicotina, glicerol e propilenoglicol em e-líquido de acordo com a ISO 20714. Este documento foi preparado por membros da Rede de Laboratórios de Tabaco da Organização Mundial da Saúde (OMS) (TobLabNet) em cooperação com os laboratórios membros da Ação Europeia Conjunta para o Controle do Tabagismo (JATC) como um procedimento operacional padrão (POP) do método analítico para determinação de nicotina, glicerol e propilenoglicol em e-líquido.

Effects of open-label transdermal nicotine antidepressant augmentation on affective symptoms and executive function in late-life depression.

BACKGROUND: Late-life depression (LLD) is characterized by a poor response to antidepressant medications and diminished cognitive performance, particularly in executive functioning. There is currently no accepted pharmacotherapy for LLD that effectively treats both mood and cognitive symptoms. This study investigated whether transdermal nicotine augmentation of standard antidepressant medications benefitted mood and cognitive symptoms in LLD. METHODS: Nonsmoking participants aged 60 years or older with unremitted LLD on stable SSRI or SNRI medications (N = 29) received transdermal nicotine patches up to a 21 mg daily dose over 12 weeks. Clinical measures assessed depression severity, secondary affective symptoms, and cognitive performance. Nicotine metabolite concentrations were obtained from blood samples. RESULTS: Depression severity significantly decreased over the trial, with a 76 % response rate and 59 % remission rate. Change in depression severity was positively associated with nicotine exposure. Participants also exhibited improvement in self-reported affective symptoms (apathy, insomnia, rumination, and generalized anxiety symptoms), negativity bias, and disability. Executive function test performance significantly improved, specifically in measures of cognitive control, as did subjective cognitive performance. Adverse events were generally mild, with 75 % of the sample tolerating the maximum dose. CONCLUSION: The current study extends our previous pilot open-label trial in LLD, supporting feasibility and tolerability of transdermal nicotine patches as antidepressant augmentation. Although preliminary, this open-label study supports the potential benefit of transdermal nicotine patches for both mood and cognitive symptoms of LLD. Further research, including definitive randomized, blinded trials, is warranted to confirm these findings and explore long-term risk and benefit. TRIAL REGISTRATION: The study was registered with clinicaltrials.gov (NCT04433767).

Assessing the Consequences of Smoking Tobacco Products with Consideration of the Forced Oscillation Technique.

BACKGROUND The effects of cigarette smoking on the health of active smokers and passive smokers have long been known, in contrast to the effects of alternative forms of nicotine intake that are gaining popularity. The aim of the study was to assess the effects of smoking traditional cigarettes and alternative forms of nicotine intake on the functional state of the respiratory system of smokers and non-smokers. MATERIAL AND METHODS Study participants (n=60) were divided into 3 groups: non-smokers (control group), cigarette smokers, and nicotine alternative users. Respiratory function testing (spirometry), forced oscillation technique, and measurement of respiratory muscle strength (PImax, PEmax) were performed. All of the above respiratory function tests were performed in accordance with European Respiratory Society and American Thoracic Society recommendations. RESULTS Smokers and those using alternative forms of nicotine intake had significantly higher values, including resistance at 5 Hz% and 11 Hz%, among others. CONCLUSIONS Smokers and users of alternative forms of nicotine are characterized by reduced flow through the small bronchioles, as evidenced by a reduction in maximal expiratory flow at 25% of vital capacity. Smokers and users of alternative forms of nicotine have higher resistance values at the height of small and medium bronchioles. Assessment method of technical forced oscillation parameters is simple to perform to detect early airway changes and is an important element in the early diagnosis of changes in smokers. The correlation analysis showed a significant correlation between age of smoking initiation/use of alternative forms of nicotine and changes in mid bronchial resistance.

Pulsed nicotine infusions as a model for smoking: validating a tool to explore nicotine thresholds in humans.

RATIONALE: No previous studies examined the discriminative stimulus effects of intravenous (IV) nicotine in humans. OBJECTIVES: To evaluate a pulsed IV nicotine infusion procedure designed to mimic inhaled nicotine delivery and to identify a range of nicotine doses that may capture the threshold doses for the subjective and discriminative stimulus effects of nicotine. By determining these thresholds, we can gain valuable insights into the addictive threshold of nicotine. METHODS: Eleven participants had 2 Test Sessions following overnight abstinence from smoking. Test Session 1 examined participants' ability to discriminate 0.1 mg nicotine/pulse nicotine from saline. Test Session 2 examined if participants can discriminate 0.05, 0.025, and 0.0125 mg nicotine/pulse of nicotine from saline. These nicotine doses were delivered as a cluster of 4 pulsed-nicotine infusions of 2-second duration with a 28-second interval between each pulse. RESULTS: The lowest doses of nicotine that produced greater responses than saline for discrimination, subjective effects, and heart rate ranged from 0.05 to 0.1 mg nicotine/pulse. CONCLUSIONS: These findings support the validity of our pulsed-infusion procedure as a model for nicotine delivery by smoking and its utility in examining factors that may impact the addictive threshold of nicotine.