Nicotine Content Research Articles

New Au/chitosan nanocomposite modified carbon paste sensor for voltammetric detection of nicotine

A profoundly touchy voltammetric sensor for detection of nicotine (NIC) in urine and tobacco specimens has been developed in light of the boosted electrochemical response of NIC at gold and chitosan nanocomposite modified carbon paste electrode (ACMCPE). Material characterization techniques Scanning Electron Microscope and Energy Dispersive X-ray (SEM & EDX) were utilized to describe the ACMCPE surface material. The impedance spectroscopy technique (EIS), cyclic voltammetry (CV), chronoamperometry (CA), and differential pulse voltammetry (DPV) were employed to explore the electrochemical sensing of NIC at ACMCPE. The created sensor exhibits an exceptional electrochemical sensitivity to NIC in a universal Britton–Robinson (B-R) buffer solution with a pH range of 2.0 to 8.0. The sensor shows a linear response over NIC concentration ranges of 4.0–320.0 µM, with the detection limit (LOD) of 7.6 µM. The prepared sensor has been shown to be exceptionally viable in detecting NIC with amazing selectivity and reproducibility. We suggest it as a trustworthy and useful electrochemical sensor for NIC location.

Effect of nicotine corrective messaging on nicotine-related beliefs in US adults: a randomised controlled trial

IntroductionWidespread misperceptions of the health risks of nicotine could undermine the public health benefits of the Food and Drug Administration’s actions, including modified risk tobacco product authorisations and a reduced...

Isolation of starch and protein degrading strain Bacillus subtilis FYZ1-3 from tobacco waste and genomic analysis of its tolerance to nicotine and inhibition of fungal growth.

Aerobic fermentation is an effective technique for the large-scale processing of tobacco waste. However, the specificity of the structure and composition of tobacco-derived organic matter and the toxic alkaloids in the material make it currently difficult to directly use microbial agents. In this study, a functional strain FYZ1-3 was isolated and screened from thermophilic phase samples of tobacco waste composting. This strain could withstand temperatures as high as 80°C and grow normally at 0.6% nicotine content. Furthermore, it had a strong decomposition capacity of tobacco-derived starch and protein, with amylase activity of 122.3 U/mL and protease activity and 52.3 U/mL, respectively. To further understand the mechanism of the metabolic transformation of the target, whole genome sequencing was used and the secondary metabolite gene cluster was predicted. The inhibitory effect of the strain on common tobacco fungi was verified using the plate confrontation and agar column methods. The results showed that the strain FYZ1-3 was Bacillus subtilis, with a genome size of 4.17 Mb and GC content of 43.68%; 4,338 coding genes were predicted. The genome was annotated and analyzed using multiple databases to determine its ability to efficiently degrade starch proteins at the molecular level. Moreover, 14 functional genes related to nicotine metabolism were identified, primarily located on the distinct genomic island of FYZ1-3, giving a speculation for its nicotine tolerance capability on the molecular mechanism. By mining the secondary metabolite gene cluster prediction, we found potential synthetic bacteriocin, antimicrobial peptide, and other gene clusters on its chromosome, which may have certain antibacterial properties. Further experiments confirmed that the FYZ1-3 strain was a potent growth inhibitor of Penicillium chrysogenum, Aspergillus sydowii, A. fumigatus, and Talaromyces funiculosus. The creation and industrial use of the functional strains obtained in this study provide a theoretical basis for its industrial use, where it would be of great significance to improve the utilization rate of tobacco waste.

Nasal airway inflammatory responses and pathogen detection in infants with cystic fibrosis

BackgroundDetecting airway inflammation non-invasively in infants with cystic fibrosis (CF) is difficult. We hypothesized that markers of inflammation in CF [IL-1β, IL-6, IL-8, IL-10, IL-17A, neutrophil elastase (NE) and tumor necrosis factor (TNF-α)] could be measured in infants with CF from nasal fluid and would be elevated during viral infections or clinician-defined pulmonary exacerbations (PEx). MethodsWe collected nasal fluid, nasal swabs, and hair samples from 34 infants with CF during monthly clinic visits, sick visits, and hospitalizations. Nasal fluid was isolated and analyzed for cytokines. Respiratory viral detection on nasal swabs was performed using the Luminex NxTAG® Respiratory Pathogen Panel. Hair samples were analyzed for nicotine concentration by reverse-phase high-performance liquid chromatography. We compared nasal cytokine concentrations between the presence and absence of detected respiratory viruses, PEx, and smoke exposure. ResultsA total of 246 samples were analyzed. Compared to measurements in the absence of respiratory viruses, mean concentrations of IL-6, IL-8, TNF-α, and NE were significantly increased while IL-17A was significantly decreased in infants positive for respiratory viruses. IL-17A was significantly decreased and NE increased in those with a PEx. IL-8 and NE were significantly increased in infants with enteric pathogen positivity on airway cultures, but not P. aeruginosa or S. aureus. Compared to those with no smoke exposure, there were significantly higher levels of IL-6, IL-10, and NE in infants with detectable levels of nicotine. ConclusionsNoninvasive collection of nasal fluid may identify inflammation in infants with CF during changing clinical or environmental exposures.

Concept flavor e-cigarette unit sales in the U.S.: 2019–2022

IntroductionConcept flavor e-cigarettes, defined as products with vague/ambiguous flavor (tobacco flavor and non-tobacco flavor) names, may limit the intended impact and enforcement of flavored tobacco restrictions. This study assessed trends in unit sales of concept flavor e-cigarettes in the U.S. by volume, nicotine concentration levels (NCL), flavor and device type. MethodsWe analyzed NielsenIQ Retail Scanner point-of-sales data collected from 2182 Local Trade Areas in the contiguous 48 U.S. states and the District of Columbia aggregated weekly from August 10, 2019, through April 9, 2022. Concept flavors were categorized by: flavor type (tobacco, fruity, menthol, mint, and other); device type (pods/refillable cartridges, disposables, e-liquids, and other); and NCL (0 %-2.0 %, 2.1 %-4.0 %, > 4.1 %, unknown). Joinpoint regression was used to assess sales trends. ResultsOverall unit sales during the study period increased by 33.63 % from 1040.85 to 1390.88 thousand units per month (p = 0.006). Between August 2019 and September 2021, unit sales increased and peaked; between September 2021 and April 2022 sales decreased by 14.46 % (from 1626.02 to 1390.88 thousand units; p = 0.002). Sales of fruity, menthol and mint flavors concept flavor e-cigarettes increased by > 1000 %; disposable devices by 302.18 %; pods and refillable cartridges by 33.81 % overall; and products NCL > 4.0 % increased by 110.18 %. Tobacco flavor concept flavors (93.28 %), pods (94.63 %), and products with 2.1 %-4.0 % NCL (88.40 %) dominated unit share. ConclusionSustaining the recent overall decline in the unit sales of concept flavor e-cigarettes and monitoring the sales of products with nicotine concentration greater than 2.0%, non-tobacco flavor, and pod products warrant prioritization in tobacco control efforts.

Effects of ‘Ice’ flavoured e-cigarettes with synthetic cooling agent WS-23 or menthol on user-reported appeal and sensory attributes

BackgroundThis clinical experiment tested the effects of exposure to e-cigarettes with WS-23 or menthol cooling additives on user appeal and sensory attributes, and, secondarily, whether WS-23 effects generalised across base...

Nicotine mediated epithelial modulations: An in-vitro evidence

IntroductionNicotine, the main ingredient in tobacco, acts as a key alkaloid of nearly all tobacco products and has been demonstrated to facilitate tumorigenesis and accelerate metastasis. Further traditional tobacco products have shown to give systemic oral effects such as vasoconstriction, inflammation, and delayed wound healing, however; none of the reports have confirmed the significant knowledge of oral sequel of the effect of nicotine on oral epithelial cells. So, the current study aimed to investigate the effect of nicotine on epithelial transformation to a malignant state. Material & methodsThrough in-vitro experiments, the effects of nicotine on epithelial cells obtained from nicotine never exposed buccal mucosa were analyzed using total count and viability test, proliferation assay, cell cycle distribution assay, and PI3K/MAPK dual pathway activation assay. Result & conclusionMTT assay demonstrated that the proliferation of epithelial cells takes place at a 150 mM concentration of nicotine. Further, we identified the significantly increased cell count and viability in nicotine-exposed cells. Further, cell cycle distribution assay results demonstrated that nicotine forced the epithelial cells to enter the first growth phase. The same influence of nicotine was observed on the PI3K/MAPK dual pathway activation assay where a greater number of nicotine exposed cells showed dual pathway activation. In conclusion, the current study determined the potential mechanism of action of nicotine on oral epithelial cell proliferation through activating the oncogenic pathway. This may help to develop novel therapeutic strategies for the prevention of malignant transformation from smokeless tobacco-caused oral cancer.

Characterization of physiochemical parameters & their effect on microbial content of smokeless tobacco products marketed in north India.

Smokeless tobacco (SLT) product consumption has profound public health implications for its users. The p H and moisture of SLTs determine the bioavailability of nicotine, the microbial structure dynamics and the amount of microbial conversion of tobacco alkaloids to carcinogenic tobacco-specific nitrosamines. This study aimed to characterize and compare the p H, moisture and alkaloid content of various SLT products. Thirty-seven SLT samples including khaini , snus, moist snuff, gul , pan masala , zarda , Mainpuri kapoori and qiwam were collected from the retail market around the National Capital Region in north India and their p H, moisture, nicotine and alkaloid content were measured. The p H and total nicotine were used to calculate the amount of free nicotine, the readily absorbed form, for each product by applying the Henderson-Hasselbalch equation. The investigation showed that the SLTs varied drastically in their p H (5.36 to 10.27), moisture content (4.7 to 51.7%) and alkaloid content (0.82 to 35.87 mg/g). The p H and free nicotine levels of a product were found to be positively correlated, and the highest free nicotine content was reported in snus samples. Further, the moisture content was seen to impact the bacterial and fungal diversity in these samples. Studies to detect the presence of pathogenic microbiological genera as well as potentially toxic constituents are warranted. The use of SLTs as an alternative to cigarette smoking should be discouraged, and cessation programmes must call attention to their detrimental effects and emphasize on benefits of quitting SLT consumption.

Passive Smoking And The Health Of Children: A Primary Concern In Pakistan.

Dear Madam, Environmental tobacco smoke (ETS), also referred to as second-hand, involuntary, or passive smoke, is produced from the combustion of tobacco products or puffed out by active smokers. The smoke emitted from the tip of a cigarette contains about two times the concentration of nicotine, five times the concentration of Carbon monoxide, and 50 times the concentration of ammonia than active smoke1. Furthermore, amongst the exposed population, children are far more susceptible to complications associated with ETS due to their manner of exposure and developmental physiology. According to the 2014 Global Adult Tobacco Survey for Pakistan, 43.3% of households were exposed to ETS, with a significant amount of children included in that percentage2. Thus, children's health is more detrimentally impacted by ETS than adults. Exposure of children to ETS in domestic and public settings risks a higher occurrence of respiratory and middle-ear diseases. According to numerous studies, dose-dependent exposure to ETS directs more frequent and severe asthma attacks accompanied by wheezing. Moreover, it is observed that school-aged individuals who live in a smoking household tend to develop a range of lung diseases, including bronchitis, bronchiolitis, and pneumonia. Their lungs become weak, resulting in impaired pulmonary function3. With reference to a population-based cohort study conducted by Lovasi et al. (ref 4), it was evident that childhood ETS exposure from 2 or more smokers compared with none is linked with early emphysema in adulthood4. In addition, constant ETS exposure leads to swelling and obstruction of the eustachian tube, which interferes with pressure equalization leading to pain, fluid accumulation, and infection. Ear infections and middle ear fluid are the most common causes of hearing loss in children. Being the primary reason behind several disease, ETS is also known to cause acute effects on cardiovascular function in children. Compelling evidence demonstrates that childhood ETS exposure risks the accumulation of factors associated with cardiovascular diseases, including obesity, dyslipidemia, and imbalanced systolic and diastolic blood pressure5. [Exposure to hazardous chemicals found in ETS, for instance, benzopyrene, is known to accelerate the development of atherosclerosis]. Moreover, studies show convincing evidence that hypertension is common in children exposed to ETS at home. It is also observed that hypertension is a common risk factor for cardiovascular disease and cardiovascular stress hyperactivity in children with smoking parents. ---Continue

Radiocarbon Flux Measurements Reveal Mechanistic Insight into Heat-Stress Induction of Nicotine Biosynthesis in Nicotiana attenuata.

The effect of high-temperature (HT) stress on nicotine biosynthesis in Nicotiana attenuata was examined. Nicotine content was measured in mature leaves, young sink leaves, and in roots from well-watered plants grown at 25 °C as controls and from plants exposed to 38 °C and 43 °C temperatures applied for 24, 48, 72, and 96 h duration. At 38 °C, all leaf nicotine levels were significantly less than control plants for up to 72 h exposure but rose sharply thereafter to levels significantly greater than controls with 96 h exposure. In contrast, plants exposed to 43 °C never exhibited a reduction in leaf nicotine content and showed an increase in content with just 48 h exposure. Using radioactive 11CO2 and 13NO3-, we found that HT stress reduced both CO2 fixation and nitrate uptake. Furthermore, radiocarbon flux analysis revealed that 'new' carbon partitioning (as 11C) into the 11C-radiolabeled amino acid (AA) pool was significantly reduced with HT stress as were yields of [11C]-aspartic acid, an important AA in nicotine biosynthesis, and its beta-amido counterpart [11C]-asparagine. In contrast, [12C]-aspartic acid levels appeared unaffected at 38 °C but were elevated at 43 °C relative to controls. [12C]-Asparagine levels were noted to be elevated at both stress temperatures. Since HT reductions in carbon input and nitrogen uptake were noted to impede de novo AA biosynthesis, protein degradation at HT was examined as a source of AAs. Here, leaf total soluble protein (TSP) content was reduced 39% with long exposures to both stress temperatures. However, Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) which was 41% TSP appeared unaffected. Altogether, these results support the theory that plant proteins other than Rubisco degrade at elevated temperatures freeing up essential AAs in support of nicotine biosynthesis.

Pharmacokinetic and pharmacodynamic studies of nicotine in rat brain: a simultaneous investigation of nicotine metabolites and the release of neurotransmitters in vivo.

Introduction: The body's ability to metabolize nicotine and the disposition of nicotine in the brain are important determinants of its exposure. Limited knowledge about the near real-time changes of neurochemicals during the brain nicotine metabolic process hinders the recognition of its multiple neuropharmacological effects. Methods: An online microdialysis coupled with UHPLC-HRMS/MS method for the in vivo multi-analysis of nicotine metabolites and several neurotransmitters in rat brain was developed. Whether the systemic modulation of metabolic enzyme CYP2B would modulate nicotine pharmacokinetics and local neurochemical effects was further investigated. Results: The dynamic profiles of over 10 nicotine metabolites and neurotransmitters were simultaneously obtained after a single injection of nicotine (2mg·kg-1, i.p.) using the new method. Proadifen pretreatment (50mg·kg-1·d-1, i.p., 4days) caused significant inhibition of brain CYP2B1 activity. When exposed to nicotine, the brain C max of nicotine was 1.26 times higher and the levels of nicotine metabolites, nornicotine, and nicotine-N-oxide, were decreased by 85.3% and 34.4% in proadifen-pretreated rats. The higher level of brain nicotine induced a greater release of dopamine, serotonin, glutamate, and γ-amino-butyric acid in the nucleus accumbens. The concentrations of nicotine and dopamine were positively correlated, and the average levels of γ-amino-butyric acid and serotonin were 2.7 and 1.2 times higher, respectively, under the inhibition of nicotine metabolism. Discussion: These results demonstrated that inhibiting nicotine metabolism in rats can enhance the residence of brain nicotine and its local neurotransmitter effects. The metabolic activity of nicotine under different physiological conditions could regulate nicotine's bioavailability and its resulting pharmacology.

Comparative effect of anthocyanin on proliferation and migration of human gingival fibroblasts in the absence or presence of nicotine.

Oral fibroblast malfunction can result in periodontal diseases. Nicotine can prolong the healing process as an irritant of oral tissues. Anthocyanins have been demonstrated to have potential benefits in preventing or treating smoking-related periodontal diseases. Cyanidin chloride's (CC's) potential in oral wound healing and the viability, proliferation, and migration of human gingival fibroblasts (HGFs) were examined in the presence and absence of nicotine by an in vitro study. The effects of different nicotine concentrations (1, 2, 3, 4, and 5 mM) on the viability and proliferation of HGF cells were evaluated in the presence and absence of different CC concentrations (5, 10, 25, and 50 μM) using the quantitative MTT assay. The scratch test was performed to evaluate the migration of CC-treated cells in the presence of 2.5-mM nicotine. No cytotoxicity was observed at 1‒100 μM CC concentrations after 24, 48, and 72 hours of exposure to HGF cells. However, a concentration of 200 μM significantly reduced cell viability by about 20% at all the three-time intervals (P<0.05). Also, 3‒5-mM concentrations of nicotine significantly reduced cell viability in a dose- and time-dependent manner. Moreover, the understudied CC concentrations decreased nicotine's adverse effects on cell migration to some extent. Although the understudied CC concentrations could not significantly reduce the adverse effects of understudied nicotine concentrations on the viability and proliferation of HGF cells, they were able to reduce the detrimental effects of nicotine on cell migration significantly.

Association of Smoke and Nicotine Product Consumption With Sensorineural Hearing Loss: A Population-Level Analysis.

To test the hypothesis that use of cigarettes or other products with either cigarette-like smoke profile or high nicotine content by young populations increases the odds of developing sensorineural hearing loss (SNHL). Retrospective cohort study. TriNetX US Collaborative Network (2003-2022). Approximately 3.6 million patients at least 18 years old. None. The primary outcome of interest was diagnosis of SNHL, defined using medical billing codes (International Classification of Diseases, Tenth Revision, Current Procedural Terminology, etc.). Cohort inclusion criteria included electronic health record entry after 2003, age 18 to 54 or 55+ years at index, and status of cigarette, noncigarette nicotine, or cannabis use. Covariates were controlled via 1:1 propensity score matching for SNHL-related conditions, including diabetes mellitus and ischemic diseases. Odds for developing SNHL were calculated against control subjects aged 18 to 54 years who have no record of nicotine/cannabis use. Odds for developing SNHL are higher for people 18 to 54 years old who use any nicotine product (odds ratio [95% confidence interval], 5.91 [5.71-6.13]), cigarettes only (4.00 [3.69-4.33]), chewing tobacco only (9.04 [7.09-11.63]), or cannabis only (3.99 [3.60-4.44]) compared with control. People 55+ years old who use no products also showed increased odds for SNHL (4.73 [4.63-4.85]). Both nicotine and smoke exposure seem to be strongly associated with increased odds for developing SNHL, with chewing tobacco having the strongest association.

An 8-year longitudinal study of long-term, continuous users of electronic cigarettes

Background and AimsE-cigarettes have been available for over 15 years, but relatively little is known about long-term users. Our aim was to describe change over time in behaviours, attitudes and dependence in long-term users. Design and ParticipantsA longitudinal study of 375 e-cigarette users enrolled on the Internet in 2012–2016 and surveyed again in 2021 (8 years later on average), who continuously used e-cigarettes in the interval. FindingsFewer people in 2021 (11 %) than at baseline (33 %) had smoked tobacco in the past 31 days. Participants switched from second-generation models at baseline (e.g. Ego) to box mods in 2021 (e.g. iStick), they used larger refill bottles, they used home-made e-liquids twice as often, they used tobacco flavours less often and the nicotine concentration in e–liquids decreased from 12 to 6 mg/mL. There was no change over time in the time to the first e-cigarette puff of the day, but an e-cigarette dependence score of 0–100 decreased from 75 to 60, the frequency and strength of urges to vape decreased (from 31 % to 18 % of “strong” urges) and the proportion of people who said they would be likely to succeed if they tried to stop vaping increased. Compared to baseline, fewer people in 2021 reported vaping to cope with cravings or other smoking cessation symptoms, and fewer people reported vaping to quit smoking, to avoid relapse into smoking, or to reduce their tobacco consumption (p < 0.001 for all differences). ConclusionsIn long-term, continuous users, over a period of 8 years, substantial changes were observed in the models of e-cigarettes used, in the flavours and strength of e-liquids, and in the reasons for vaping. Their level of nicotine dependence tended to decrease over time. These users were satisfied with e-cigarettes and vaped mostly because they felt that vaping was less dangerous than smoking, and for enjoyment.

Ovarian toxicity of e-cigarette liquids: Effects of components and high and low nicotine concentration e-cigarette liquid in vitro.

Electronic cigarette use has become increasingly popular, with potential consequences for reproductive health. We aimed to investigate the effects of different components of e-liquid on the ovary and compare the impact of low nicotine concentration e-liquids (LN e-liquids) and high nicotine concentration e-liquids (HN e-liquids) on ovarian toxicity. A total of 378 rat ovaries were divided into seven groups, including control (no intervention), nicotine (0.05 mg/mL), flavoring (0.25 μL/mL), propylene glycol (PG) (2.5 μL/mL), vegetable glycerin (VG) (2.0 μL/mL), LN e-liquid (0.05 mg nicotine + 0.25 μL flavoring + 2.5 μL PG + 2.0 μL VG + 0.25 μL distilled water/mL medium) and HN e-liquid groups (0.05 mg nicotine + 0.05 μL flavoring + 0.5 μL PG + 0.4 μL VG + 0.05 μL distilled water/mL medium). After three hours of in vitro culture, ovarian morphology, oxidation levels [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA)], and apoptosis levels [factor related apoptosis (Fas), Cyt-c, Caspase-9, Caspase-3] were analyzed. Our findings indicate that nicotine has limited impact on the ovary, while flavoring, PG, and VG all cause ovarian damage including morphological damage, disruption of oxidative balance and promotion of apoptosis, with VG having the most significant effect. Moreover, LN e-liquids may lead to more severe ovarian damage than HN e-liquids at an equal intake of total nicotine. Our study highlights that in e-liquid formula, nicotine has a limited effect on the ovaries, but flavoring, PG, and VG all cause damage to the ovaries, with VG the most damaging. At a consistent level of total nicotine intake, e-liquids with low nicotine concentrations cause more damage to the ovaries than those with high nicotine concentrations. These findings contribute to a better understanding of the impact of e-liquids on ovarian health and have important implications for public health policy.

Vaping among young people-Our best defence is self-defence.

Use of electronic cigarettes (e-cigarettes or 'vapes') has risen rapidly among young Australians in recent years. To combat this, on 2 May 2023, the Albanese Government announced a suite of reforms to reduce the desirability and accessibility of e-cigarettes to young people-including a ban on disposable e-cigarettes, restricting flavours, colours and nicotine content and requiring pharmaceutical-like packaging. While many have welcomed this announcement, the efficacy of such reforms in reducing the availability of e-cigarettes to young people remain to be seen, particularly given the current prescription-only model has done little to curb youth vaping. We argue that, in an uncertain landscape where e-cigarettes will likely remain accessible and desirable to young people, it is critical that we also upskill, empower and arm our young people with the skills, resilience, resources and knowledge to make informed and positive health decisions so that: (i) fewer young people opt to take up vaping (primary prevention); and (ii) among those who already do vape, more seek help earlier on to reduce or cease their use before dependency develops (secondary prevention). Schools are an ideal setting for the delivery of these programs, where they can be delivered en masse, integrated into existing alcohol and other drug programs and aligned with school curricula. Skills-based school prevention programs have demonstrated significant and sustained reductions in drug-related harms up to 7 years post-intervention. For as long as vapes remain widely available, desirable and purposefully marketed towards young people, we believe our best defence is self-defence.

Electronic Nicotine, Non-Nicotine Delivery Systems, and Liquid Use by Flavoring and Nicotine Concentrations

Electronic Nicotine, Non-Nicotine Delivery Systems, and Liquid Use by Flavoring and Nicotine Concentrations

Effects of E-Cigarette Vapor Smoke on Pulmonary Alveoli in Rattus norvegicus Lungs

Introduction: Vapor is considered a safer alternative to tobacco cigarettes because the high nicotine content is less. However, vapor still contains substances that are classified as toxic to humans. Short-term exposure to vapors from liquids can induce an inflammatory response in the lungs and cause oxidative stress. This study aimed to determine the effects of e-cigarette vapor smoke on pulmonary alveoli in Rattus norvegicus lungs. Methods: This was an experimental study on 32 adult male Rattus norvegicus rats. They were divided into two groups exposed to nicotine-containing vapor smoke two times a day for one and three months, respectively, and one group as control. After vapor exposure, the lung tissues of the rats were taken and then subjected to histopathological examination under a microscope. Results: After exposure for one month, epithelial and endothelial cells degenerated, characterized by a decrease in collagen and elastin fibers in the extracellular matrix. For three months, there were changes, the alveolar membrane had no nucleus, the surrounding endothelial cells were not visible due to damage to the extracellular matrix, the alveolar lumen had widened, causing edema in the lumen of the alveoli, and the alveoli wall was destroyed. Therefore, the connection between the alveoli was stretched. Conclusion: This study found that short-term exposure to nicotine vapor causes damage to the alveoli membrane.

Pharmacological effects of nicotine salts on dopamine release in the nucleus accumbens.

With the growing number of individuals regularly using e-cigarettes, it has become increasingly important to understand the psychobiological effects of nicotine salts. Nicotine increases the release of dopamine (DA) into the nucleus accumbens (NAc), causing feelings of satisfaction. However, the differences in the DA-increasing effects of different nicotine salts have not been reported. In this study, we used a G protein-coupled receptor-activated DA fluorescent probe (GRABDA1m) and optical fiber photometric recording equipment to monitor the dynamic changes and kinetics of DA release in the NAc of mice exposed to different e-cigarette aerosols, including nicotine, nicotine benzoate, nicotine tartrate, nicotine lactate, nicotine levulinic acid, nicotine malate, and nicotine citrate. The results of this study were as follows: 1) Different types of nicotine salts could increase the release of DA in the NAc. 2) The slopes and half-effective concentrations of the fitted curves were different, suggesting that each nicotine salt had a difference in the efficiency of increasing DA release with concentration changes. 3) The absorption rates of different nicotine salts containing the same original nicotine concentration were significantly different by measuring the blood nicotine content. The effect of nicotine salts on increasing DA was directly proportional to the blood nicotine level. In conclusion, by observing the effects of nicotine salts on DA release in real time in vivo, differences in the pharmacological effects of nicotine salts are revealed to better understand the mechanism underlying the regulatory effects of nicotine salts on the brain.

Varied effects of tobacco smoke and e-cigarette vapor suggest that nicotine does not affect endothelium-dependent relaxation and nitric oxide signaling

Chronic smoking causes dysfunction of vascular endothelial cells, evident as a reduction of flow-mediated dilation in smokers, but the role of nicotine is still controversial. Given the increasing use of e-cigarettes and other nicotine products, it appears essential to clarify this issue. We studied extracts from cigarette smoke (CSE) and vapor from e-cigarettes (EVE) and heated tobacco (HTE) for their effects on vascular relaxation, endothelial nitric oxide signaling, and the activity of soluble guanylyl cyclase. The average nicotine concentrations of CSE, EVE, and HTE were 164, 800, and 85 µM, respectively. At a dilution of 1:3, CSE almost entirely inhibited the relaxation of rat aortas and porcine coronary arteries to acetylcholine and bradykinin, respectively, while undiluted EVE, with a 15-fold higher nicotine concentration, had no significant effect. With about 50% inhibition at 1:2 dilution, the effect of HTE was between CSE and EVE. Neither extract affected endothelium-independent relaxation to an NO donor. At the dilutions tested, CSE was not toxic to cultured endothelial cells but, in contrast to EVE, impaired NO signaling and inhibited NO stimulation of soluble guanylyl cyclase. Our results demonstrate that nicotine does not mediate the impaired endothelium-dependent vascular relaxation caused by smoking.