Analysis of complex mixtures--cigarette smoke

Anti-atherogenic role of green tea (Camellia sinensis) in South Indian smokers

ETHNOPHARMACOLOGICAL RELEVANCE

Green tea (Camellia sinensis) is a popular beverage consumed all over the world due to its health benefits. Many of these beneficial effects of green tea are attributed to polyphenols, particularly catechins.

AIM OF THE STUDY

The present study focuses on underlying anti-platelet aggregation, anti-thrombotic, and anti-lipidemic molecular mechanisms of green tea in South Indian smokers.

MATERIALS AND METHODS

We selected 120 South Indian male volunteers for this study to collect the blood and categorised them into four groups; control group individuals (Controls), smokers, healthy control individuals consuming green tea, and smokers consuming green tea. Smokers group subjects have been smoking an average 16-18 cigarettes per day for the last 7 years or more. The subjects (green tea consumed groups) consumed 100 mL of green tea each time, thrice a day for a one-year period.

RESULTS

LC-MS analysis revealed the presence of multiple phytocompounds along with catechins in green tea extract. Increased plasma lipid peroxidation (LPO), protein carbonyls, cholesterol, triglycerides, and LDL-cholesterol with decreased HDL-cholesterol levels were observed in smokers compared to the control group and the consumption of green tea showed beneficial effect. Furthermore, docking studies revealed that natural compounds of green tea had high binding capacity with 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMG-CoA) when compared to their positive controls, whereas (-) epigallocatechin-3-gallate (EGCG) and (-) epicatechin-gallate (ECG) had high binding capacity with sterol regulatory element-binding transcription factor 1 (SREBP1c). Further, our ex vivo studies showed that green tea extract (GTE) significantly inhibited platelet aggregation and increased thrombolytic activity in a dose dependent manner.

CONCLUSION

In conclusion, in smokers, catechins synergistically lowered oxidative stress, platelet aggregation and modified the aberrant lipid profile. Furthermore, molecular docking studies supported green tea catechins' antihyperlipidemic efficacy through strong inhibitory activity on HMG-CoA reductase and SREBP1c. The mitigating effects of green tea on cardiovascular disease risk factors in smokers that have been reported can be attributed majorly to catechins or to their synergistic effects.

More precise method of low-density lipoprotein cholesterol estimation for tobacco and electronic cigarette smokers: A cross-sectional study

Smoking is associated with elevated low-density lipoprotein cholesterol (LDL-C) levels. However, the accuracies of the Friedewald, Sampson, and Martin LDL-C-estimating equations based on smoking status are unclear. We analyzed the accuracy of LDL-C levels estimated using these three equations based on tobacco and electronic cigarette smoking status. Data on LDL-C and other lipid components were obtained from the Korea National Health and Nutrition Examination Survey from January 2009 to December 2021. Direct LDL-C (dLDL-C) levels and smoking data of 12,325 participants were evaluated. Current smokers had higher triglyceride levels than never smokers. Electronic cigarette smokers had higher triglyceride and dLDL-C levels than never smokers. The Martin equation yielded more accurate mean absolute deviations than the other equations for the group with triglyceride levels <400 mg/dL as well as more accurate median absolute deviation values, except for the group with dLDL-C levels <40 mg/dL. Similar estimates were derived from the equations when the triglyceride levels were <150 mg/dL. However, the Martin equation may lead to the overestimation of LDL-C levels. In conclusion, the Martin equation is suitable for triglyceride levels <400 mg/dL regardless of the electronic cigarette/tobacco smoking status; if the triglyceride level is <150 mg, the Friedewald equation could also be considered, regardless of the electronic cigarette/tobacco smoking status.

Tobacco and COPD: presenting the World Health Organization (WHO) Tobacco Knowledge Summary

The WHO recently published a Tobacco Knowledge Summary (TKS) synthesizing current evidence on tobacco and COPD, aiming to raise awareness among a broad audience of health care professionals. Furthermore, it can be used as an advocacy tool in the fight for tobacco control and prevention of tobacco-related disease. This article builds on the evidence presented in the TKS, with a greater level of detail intended for a lung-specialist audience. Pulmonologists have a vital role to play in advocating for the health of their patients and the wider population by sharing five key messages: (1) Smoking is the leading cause of COPD in high-income countries, contributing to approximately 70% of cases. Quitting tobacco is an essential step toward better lung health. (2) People with COPD face a significantly higher risk of developing lung cancer. Smoking cessation is a powerful measure to reduce cancer risk. (3) Cardiovascular disease, lung cancer and type-2 diabetes are common comorbidities in people with COPD. Quitting smoking not only improves COPD management, but also reduces the risk of developing these coexisting conditions. (4) Tobacco smoke also significantly impacts children's lung growth and development, increasing the risk of respiratory infections, asthma and up to ten other conditions, and COPD later in life. Governments should implement effective tobacco control measures to protect vulnerable populations. (5) The tobacco industry's aggressive strategies in the marketing of nicotine delivery systems and all tobacco products specifically target children, adolescents, and young adults. Protecting our youth from these harmful tactics is a top priority.

Exploring the Cellular Impact of Size-Segregated Cigarette Aerosols: Insights into Indoor Particulate Matter Toxicity and Potential Therapeutic Interventions

Exposure to anthropogenic aerosols has been associated with a variety of adverse health effects, increased morbidity, and premature death. Although cigarette smoke poses one of the most significant public health threats, the cellular toxicity of particulate matter contained in cigarette smoke has not been systematically interrogated in a size-segregated manner. In this study, we employed a refined particle size classification to collect cigarette aerosols, enabling a comprehensive assessment and comparison of the impacts exerted by cigarette aerosol extract (CAE) on SH-SY5Y, HEK293T, and A549 cells. Exposure to CAE reduced cell viability in a dose-dependent manner, with organic components having a greater impact and SH-SY5Y cells displaying lower tolerance compared to HEK293T and A549 cells. Moreover, CAE was found to cause increased oxidative stress, mitochondrial dysfunction, and increased levels of apoptosis, pyroptosis, and autophagy, leading to increased cell death. Furthermore, we found that rutin, a phytocompound with antioxidant potential, could reduce intracellular reactive oxygen species and protect against CAE-triggered cell death. These findings underscore the therapeutic potential of antioxidant drugs in mitigating the adverse effects of cigarette aerosol exposure for better public health outcomes.

MK2 inhibitor PF-3644022 shows protective effect in mouse microglial N9 cell line induced with cigarette smoke extract

Neuroinflammation is suggested as one of the potential links between CS-induced neuronal dysfunction. Cigarette smoke (CS) is one of the significant contributors of neuroinflammation, consequently leading to cognitive impairment and neurodegeneration. Microglia are the key resident macrophage cells in the brain with cell surface TLR4 receptor for responding to various stress signals. The CS constituents promote inflammation and oxidative stress in microglia leading to cytotoxicity through the TLR4-MK2 axis. However, the role of MK2 kinase in CS-induced microglial inflammation is not yet clearly understood. Therefore, we have used an MK2 inhibitor, PF-3644022 to study modulation of CS-extract induced oxidative and inflammatory signaling in a mouse microglial cell line, Furthermore, we also evaluated the enzymatic activity of acetylcholinesterase (AChE) on a direct exposure of enzyme with CS. CS exposure led to microglial cytotoxicity and enhanced the level of oxidative stress and proinflammatory cytokine release by microglial cells. The microglial cells pretreated with MK2 inhibitor, PF-3644022 significantly reduced the levels of oxidative stress markers, proinflammatory markers, and improved the level of antioxidant proteins in these cells. In addition, direct exposure of CS showed reduction in the enzymatic activity of AChE.

A web-based scoping review assessing the influence of smoking and smoking cessation on antidiabetic drug meabolism: implications for medication efficacy

Currently 1.3 billion individuals globally engage in smoking, leading to significant morbidity and mortality, particularly among diabetic patients. There is urgent need for a better understanding of how smoking influences antidiabetic treatment efficacy. The review underscores the role of cigarette smoke, particularly polycyclic aromatic hydrocarbons (PAHs), in modulating the metabolic pathways of antidiabetic drugs, primarily through the induction of cytochrome P450 (CYP450) enzymes and uridine diphosphate (UDP)-glucuronosyltransferases (UGTs), thus impacting drug pharmacokinetics and therapeutic outcomes. Furthermore, the review addresses the relatively uncharted territory of how smoking cessation influences diabetes treatment, noting that cessation can lead to significant changes in drug metabolism, necessitating dosage adjustments. Special attention is given to the interaction between smoking cessation aids and antidiabetic medications, a critical area for patient safety and effective diabetes management. This scoping review aims to provide healthcare professionals with the knowledge to better support diabetic patients who smoke or are attempting to quit, ensuring tailored and effective treatment strategies. It also identifies gaps in current research, advocating for more studies to fill these voids, thereby enhancing patient care and treatment outcomes for this at-risk population.

Genomic and Metagenomic Insights into the Distribution of Nicotine-degrading Enzymes in Human Microbiota

Introduction

Nicotine degradation is a new strategy to block nicotine-induced pathology. The potential of human microbiota to degrade nicotine has not been explored.

Aims

This study aimed to uncover the genomic potentials of human microbiota to degrade nicotine.

Methods

To address this issue, we performed a systematic annotation of Nicotine-Degrading Enzymes (NDEs) from genomes and metagenomes of human microbiota. A total of 26,295 genomes and 1,596 metagenomes for human microbiota were downloaded from public databases and five types of NDEs were annotated with a custom pipeline. We found 959 NdhB, 785 NdhL, 987 NicX, three NicA1, and three NicA2 homologs.

Results

Genomic classification revealed that six phylum-level taxa, including Proteobacteria, Firmicutes, Firmicutes_A, Bacteroidota, Actinobacteriota, and Chloroflexota, can produce NDEs, with Proteobacteria encoding all five types of NDEs studied. Analysis of NicX prevalence revealed differences among body sites. NicX homologs were found in gut and oral samples with a high prevalence but not found in lung samples. NicX was found in samples from both smokers and non-smokers, though the prevalence might be different.

Conclusion

This study represents the first systematic investigation of NDEs from the human microbiota, providing new insights into the physiology and ecological functions of human microbiota and shedding new light on the development of nicotine-degrading probiotics for the treatment of smoking-related diseases.

Kinetic and thermodynamic investigation of Rhodanese synthesized by enhanced Klebsiella oxytoca JCM 1665 strain: a comparative between the free and immobilized enzyme entrapped in alginate beads

Klebsiella oxytoca JCM 1665 was subjected to extracellular rhodanese production using a submerged fermentation technique. The organism was further engineered for higher cyanide tolerance and rhodanese yield using ethylmethanesulfonate as a mutagen. Mutagenesis resulted in an improved mutant with high cyanide tolerance (100 mM) and rhodanese yield (26.7 ± 0.67 U/mL). This yield was 4.34-fold higher than the wild strain (6.15 ± 0.65 U/mL). At temperatures ranging from 30 to 80 °C, the first-order thermal denaturation constant (Kd) for free enzyme increases from 0.00818 to 0.0333 min-1 while the immobilized enzyme increases from 0.003 to 0.0204 min-1. The equivalent half-life reduces from 99 to 21 minutes and 231 to 35 minutes, respectively. Residual activity tests were used to assess the thermodynamic parameters for both enzyme preparations. For the free enzyme, the parameters obtained were enthalpy (29.40 to 29.06 kJ.mol-1), entropy (-194.24 to -197.50 J.mol-1K-1) and Gibbs free energy (90.20 to 98.80 kJ.mol-1). In addition, for immobilized rhodanese, we obtained enthalpy (40.40 to 40.07 kJ.mol-1), entropy (-164.21 to - 165.20 J.mol-1K-1) and Gibbs free energy (91.80 to 98.40 kJ.mol-1. Regarding its operational stability, the enzyme was able to maintain 63% of its activity after being used for five cycles. Immobilized K. oxytoca rhodanese showed a marked resistance to heat inactivation compared to free enzyme forms; making it of utmost significance in many biotechnological applications.

Differences in Airway Remodeling and Emphysematous Lesions between Rats Exposed to Smoke from New-Type and Conventional Tobacco Varieties

Genes from Perilla frutescens and Ocimum basilicum were introduced into N. tabacum L. var. HHY via distant hybridization, and the new-type tobacco varieties "Zisu" and "Luole" were developed, with noticeable differences in chemical composition. Smoking is the leading cause of chronic obstructive pulmonary disease (COPD), and its pathogenesis is complex. In the present study, 48 male Sprague-Dawley (SD) rats were randomly divided into four groups, namely, the control, "HHY", "Zisu" and "Luole", and then exposed to fresh air/cigarette smoke (CS) for 30 days and 60 days. The COPD model was constructed, and their health hazards were compared and evaluated. CS from different tobacco varieties influenced rats in varying degrees at the tissue, cell and molecular levels. The rats in the "HHY" group showed obvious symptoms, such as cough and dyspnea, which were less severe in the "Zisu" and "Luole" groups. Pathological and morphological analyses, including scores, MLI, MAN, WAt/Pbm and WAm/Pbm, showed that "Zisu" and "Luole" caused less damage to the airways and lung parenchyma than "HHY". Significant increases in the numbers of total leukocytes and neutrophils in the BALF were found in "HHY" compared to those in "Zisu" and "Luole". Moreover, they caused less oxidative stress and apoptosis in lung tissues, as reflected by indicators such as ROS, MDA, T-AOC, GSH, the apoptotic index and the ratio of Bcl-2 to Bax. "Zisu" and "Luole" even altered the ratios of MMP-9/TIMP-1 and IFN-γ/IL-4 in lung tissues to a lesser degree. These differences between CS-exposed rats may be closely related to the altered expression of Nrf2, p38 MAPK and p-p38 MAPK. Changes in chemical composition via introducing genes from some medicinal plants may be an attractive strategy for tobacco harm reduction.

Interstitial lung disease: a review of classification, etiology, epidemiology, clinical diagnosis, pharmacological and non-pharmacological treatment

Interstitial lung diseases (ILDs) refer to a heterogeneous and complex group of conditions characterized by inflammation, fibrosis, or both, in the interstitium of the lungs. This results in impaired gas exchange, leading to a worsening of respiratory symptoms and a decline in lung function. While the etiology of some ILDs is unclear, most cases can be traced back to factors such as genetic predispositions, environmental exposures (including allergens, toxins, and air pollution), underlying autoimmune diseases, or the use of certain medications. There has been an increase in research and evidence aimed at identifying etiology, understanding epidemiology, improving clinical diagnosis, and developing both pharmacological and non-pharmacological treatments. This review provides a comprehensive overview of the current state of knowledge in the field of interstitial lung diseases.

Comparison of emissions across tobacco products: A slippery slope in tobacco control

In this narrative review, we highlight the challenges of comparing emissions from different tobacco products under controlled laboratory settings (using smoking/vaping machines). We focus on tobacco products that generate inhalable smoke or aerosol, such as cigarettes, cigars, hookah, electronic cigarettes, and heated tobacco products. We discuss challenges associated with sample generation including variability of smoking/vaping machines, lack of standardized adaptors that connect smoking/vaping machines to different tobacco products, puffing protocols that are not representative of actual use, and sample generation session length (minutes or number of puffs) that depends on product characteristics. We also discuss the challenges of physically characterizing and trapping emissions from products with different aerosol characteristics. Challenges to analytical method development are also covered, highlighting matrix effects, order of magnitude differences in analyte levels, and the necessity of tailored quality control/quality assurance measures. The review highlights two approaches in selecting emissions to monitor across products, one focusing on toxicants that were detected and quantified with optimized methods for combustible cigarettes, and the other looking for product-specific toxicants using non-targeted analysis. The challenges of data reporting and statistical analysis that allow meaningful comparison across products are also discussed. We end the review by highlighting that even if the technical challenges are overcome, emission comparison may obscure the absolute exposure from novel products if we only focus on relative exposure compared to combustible products.

Tobacco introduced Perilla frutescens and Ocimum basilicum genes attenuates neutrophilic inflammation in lung tissues of COPD rats

The new-type tobacco varieties "Zisu" and "Luole" were obtained by distant hybridization between N. tabacum L. var. HHY and Perilla frutescens and Ocimum basilicum, with obviously different chemical composition. Smoking is the major risk factor for COPD, characterized by neutrophil-dominant inflammation. In the present study, rat COPD model was established by cigarette exposure, and the health hazard of three varieties was compared by general condition observation, pathological and morphological evaluation, total and differential cell numeration, and characterization of major inflammatory mediators and MAPK/NF-κB pathway, etc. Rats in "HHY" group developed obvious symptoms such as cough, dyspnea, mental fatigue, etc., but these symptoms were obviously mitigated in "Zisu" and "Luole" groups. H&E staining analysis, including score, MLI, MAN, wt% and WA%, showed that "Zisu" and "Luole" significantly alleviated lung injury and the degree of airway remodeling and emphysema compared to "HHY". In BALF, the number of total leukocyte and the percent neutrophils in "Zisu" and "Luole" groups were evidently lower than "HHY" group. The levels of inflammatory mediators, such as IL-8, MPO, MIP-2, LTB4, TNF-α and neutrophil elastase, in "HHY" group were obviously higher than "Zisu" and "Luole" groups. The ROS-mediated NF-κB p65 and p38MAPK pathways may play an important role. Results indicated that tobacco introduced perilla and basil genes could remarkably attenuate recruitment, infiltration and activation of neutrophils and intervene in airway inflammation, retarding disease progression, especially "Zisu". Changes in chemical composition via breeding techniques may be a novel way for tobacco harm reduction.

Alkylating agents are possible inducers of glioblastoma and other brain tumors

Epidemiological evidence of an association between exposure to chemical carcinogens and an increased risk for development of glioblastoma (GBM) is limited to weak statistical associations in cohorts of firefighters, farmers, residents exposed to air pollution, and soldiers exposed to toxic chemicals (e.g., military burn pits, oil-well fire smoke). A history of ionizing radiation therapy to the head or neck is associated with an increased risk of GBM. Ionizing radiation induces point mutations, frameshift mutations, double-strand breaks, and chromosomal insertions or deletions. Mutational profiles associated with chemical exposures overlap with the broad mutational patterns seen with ionizing radiation. Data on 16 agents (15 chemicals and radio frequency radiation) that induced tumors in the rodent brain were extracted from 602 Technical Reports on 2-years cancer bioassays found in the National Toxicology Program database. Ten of the 15 chemical agents that induce brain tumors are alkylating agents. Three of the 15 chemical agents have idiosyncratic structures and might be alkylating agents. Only two of the 15 chemical agents are definitively not alkylating agents. The rat model is thought to be of possible relevance to humans suggesting that exposure to alkylating chemicals should be considered in epidemiology studies on GBM and other brain tumors.

Traditional Therapeutics and Potential Epidrugs for CVD: Why Not Both?

Cardiovascular disease (CVD) is the leading cause of death worldwide. In addition to the high mortality rate, people suffering from CVD often endure difficulties with physical activities and productivity that significantly affect their quality of life. The high prevalence of debilitating risk factors such as obesity, type 2 diabetes mellitus, smoking, hypertension, and hyperlipidemia only predicts a bleak future. Current traditional CVD interventions offer temporary respite; however, they compound the severe economic strain of health-related expenditures. Furthermore, these therapeutics can be prescribed indefinitely. Recent advances in the field of epigenetics have generated new treatment options by confronting CVD at an epigenetic level. This involves modulating gene expression by altering the organization of our genome rather than altering the DNA sequence itself. Epigenetic changes are heritable, reversible, and influenced by environmental factors such as medications. As CVD is physiologically and pathologically diverse in nature, epigenetic interventions can offer a ray of hope to replace or be combined with traditional therapeutics to provide the prospect of addressing more than just the symptoms of CVD. This review discusses various risk factors contributing to CVD, perspectives of current traditional medications in practice, and a focus on potential epigenetic therapeutics to be used as alternatives.

Comparison of Pollutant Effects on Cutaneous Inflammasomes Activation

The skin is the outermost layer of the body and, therefore, is exposed to a variety of stressors, such as environmental pollutants, known to cause oxinflammatory reactions involved in the exacerbation of several skin conditions. Today, inflammasomes are recognized as important modulators of the cutaneous inflammatory status in response to air pollutants and ultraviolet (UV) light exposure. In this study, human skin explants were exposed to the best-recognized air pollutants, such as microplastics (MP), cigarette smoke (CS), diesel engine exhaust (DEE), ozone (O3), and UV, for 1 or 4 days, to explore how each pollutant can differently modulate markers of cutaneous oxinflammation. Exposure to environmental pollutants caused an altered oxidative stress response, accompanied by increased DNA damage and signs of premature skin aging. The effect of specific pollutants being able to exert different inflammasomes pathways (NLRP1, NLRP3, NLRP6, and NLRC4) was also investigated in terms of scaffold formation and cell pyroptosis. Among all environmental pollutants, O3, MP, and UV represented the main pollutants affecting cutaneous redox homeostasis; of note, the NLRP1 and NLRP6 inflammasomes were the main ones modulated by these outdoor stressors, suggesting their role as possible molecular targets in preventing skin disorders and the inflammaging events associated with environmental pollutant exposure.

Aerosol Emissions from Heated Tobacco Products: A Review Focusing on Carbonyls, Analytical Methods, and Experimental Quality

We provide an extensive review of 17 independent and industry-funded studies targeting carbonyls in aerosol emissions of Heated Tobacco Products (HTPs), focusing on quality criteria based on the reproducibility of experiments, appropriate analytic methods, and puffing regimes. Most revised studies complied with these requirements, but some were unreproducible, while others failed to consider analytical variables that may have affected the results and/or produced unrealistic comparisons. We also provide a review of the literature on the physicochemical properties of heated tobacco and HTP aerosols, as well as the evaluation of HTPs by regulatory agencies, addressing various critiques of their relative safety profile. The outcomes from the revised studies and regulatory evaluations tend to agree with and converge to a general consensus that HTP aerosols expose users to significantly lower levels of toxicity than tobacco smoke.

[Male infertility, environment and lifestyle]

BACKGROUND

Since the 1970s, there has been a quantitative and qualitative decline in sperm parameters. The main hypothesis to explain such a rapid evolution is the involvement of environmental and behavioral phenomena.

METHODS

A bibliographic search limited to English and French literature in men published before 7/2023 was carried out on the links between fertility and pollution, xenobiotics, tobacco, narcotics, cannabis, alcohol, weight, sport, sedentary lifestyle, sleep and anabolics.

RESULTS

Profound changes in lifestyle have occurred over the past 50 years: reduced sleep time, sedentary lifestyle, dietary changes, tobacco consumption, use of narcotics and anabolics. These changes have a proven impact on spermogram parameters, and should be corrected in an effort to optimize reproductive health. Other environmental parameters: pollution, exposure to heavy metals, exposure to xenobiotics, phthalates and pesticides… will be more difficult to exclude from patients' daily lives, but deserve to be taken more into account.

CONCLUSION

This review should help the urologist to assess and counsel patients in order to improve their reproductive health. These factors should be routinely investigated in infertile men.

Cigarette Smoke-Induced Reactive Oxygen Species Formation: A Concise Review

Smoking is recognized as a significant risk factor for numerous disorders, including cardiovascular diseases, respiratory conditions, and various forms of cancer. While the exact pathogenic mechanisms continue to be explored, the induction of oxidative stress via the production of excess reactive oxygen species (ROS) is widely accepted as a primary molecular event that predisposes individuals to these smoking-related ailments. This review focused on how cigarette smoke (CS) promotes ROS formation rather than the pathophysiological repercussions of ROS and oxidative stress. A comprehensive analysis of existing studies revealed the following key ways through which CS imposes ROS burden on biological systems: (1) ROS, as well as radicals, are intrinsically present in CS, (2) CS constituents generate ROS through chemical reactions with biomolecules, (3) CS stimulates cellular ROS sources to enhance production, and (4) CS disrupts the antioxidant system, aggravating the ROS generation and its functions. While the evidence supporting these mechanisms is chiefly based on in vitro and animal studies, the direct clinical relevance remains to be fully elucidated. Nevertheless, this understanding is fundamental for deciphering molecular events leading to oxidative stress and for developing intervention strategies to counter CS-induced oxidative stress.

Environmental tobacco smoke at home and in public places prior to smoking ban enforcement: Assessment by hair analysis in a population of young adult students

Despite inititatives to reduce tobacco consumption, smoking remains a primary cause of death for both smokers and nonsmokers exposed to environmental tobacco smoke (ETS). The characteristics of some specific groups can make them more exposed to ETS or limit the benefit of prevention measures. This study investigated determinants of ETS in a population of young adult students, considered at higher risk of exposure due to their specific lifestyle. This cross-sectional study involved 90 students aged 20 ± 1.7 years, from the University of Luxembourg, prior to the smoking ban enforcement in public places in the country. Participants reported their tobacco consumption and exposure to ETS at home and/or in public places, and provided a hair sample analyzed for nicotine and cotinine. Nicotine and cotinine were significantly higher in smokers than in nonsmokers' hair in general (median: 2.6 vs. 0.9 ng/mg and 87.1 vs. 22.5 pg/mg respectively). However, nonsmokers exposed to ETS at home and in public places had comparable concentrations to smokers (nic = 2.2 ng/mg; cot = 56.2 pg/mg), whereas unexposed nonsmokers presented significantly lower values (nic = 0.4 ng/mg, cot = 8.5 pg/mg). Nonsmokers exposed to ETS only at home presented higher values than nonsmokers only exposed in public places (nic: 1.3 vs. 0.8 ng/mg, cot: 70.4 vs. 15.0 pg/mg). The study shows the widespread exposure to ETS in this population, the importance of exposure assessment, and the relevance of hair analysis for this purpose. Results suggest that ETS can lead to equivalent exposure to active smoking and that exposure at home can highly contribute to ETS, which is not solved by smoking ban in public places.

Comparative study of the effects of cigarette smoke versus next-generation tobacco and nicotine product extracts on inflammatory biomarkers of human monocytes

Monocytes exhibiting a pro-inflammatory phenotype play a key role in adhesion and development of atherosclerotic plaques. As an alternative to smoking, next-generation tobacco and nicotine products (NGP) are now widely used. However, little is known about their pro-inflammatory effects on monocytes. We investigated cell viability, anti-oxidant and pro-inflammatory gene and protein expression in THP-1 monocytes after exposure to aqueous smoke extracts (AqE) of a heated tobacco product (HTP), an electronic cigarette (e-cig), a conventional cigarette (3R4F) and pure nicotine (nic). Treatment with 3R4F reduced cell viability in a dose-dependent manner, whereas exposure to alternative smoking products showed no difference to control. At the highest non-lethal dose of 3R4F (20%), the following notable mRNA expression changes were observed for 3R4F, HTP, and e-cig respectively, relative to control; HMOX1 (6-fold, < 2-fold, < 2-fold), NQO1 (3.5-fold, < 2-fold, < 2-fold), CCL2 (4-fold, 3.5-fold, 2.5-fold), IL1B (4-fold, 3-fold, < 2-fold), IL8 (5-fold, 2-fold, 2-fold), TNF (2-fold, 2-fold, < 2-fold) and ICAM1 was below the 2-fold threshold for all products. With respect to protein expression, IL1B (3-fold, < 2-fold, < 2-fold) and IL8 (3.5-fold, 2-fold, 2-fold) were elevated over the 2-fold threshold, whereas CCL2, TNF, and ICAM1 were below 2-fold expression for all products. At higher doses, greater inductions were observed with all extracts; however, NGP responses were typically lower than 3R4F. In conclusion, anti-oxidative and pro-inflammatory processes were activated by all products. NGPs overall showed lower responses relative to controls than THP-1 cells exposed to 3R4F AqE.

Cigarette smoke induces epithelial-to-mesenchymal transition, stemness, and metastasis in lung adenocarcinoma cells via upregulated RUNX-2/galectin-3 pathway

AIMS

An elevated level of galectin-3, a carbohydrate-binding lectin implicated in tumorigenesis, metastasis, and epithelial-mesenchymal transition (EMT), has been found in cigarette smokers. However, the regulation of its expression and role in the pathogenesis of CS-induced EMT and lung cancer metastasis is unclear. Here, we have investigated the mechanism of CS-induced and galectin-3-mediated EMT in airway epithelial cells (AECs).

MAIN METHODS

A549 adenocarcinoma cells and primary small airway epithelial cells cultured on an air-liquid interface (ALI) were exposed to cigarette smoke extract (CSE), and MTT, trypan blue, migration, invasion, tumor spheroid and colony formation assays were performed to assess EMT phenotype. Immunoblotting was performed to assess EMT and stemness markers and other regulatory proteins.

KEY FINDINGS

CSE exposure affected cell survival and morphology, migration, invasion, and clonogenicity of AECs, which were concomitant with an increase in the expression of EMT markers, galectin-3, and runt-related transcription factor-2 (RUNX-2), an osteogenic transcription factor and upstream regulator of galectin-3. Chemical inhibition or silencing of RUNX-2 downregulated galectin-3 and modulated EMT marker expression, migration, invasion, and clonogenicity in CSE-exposed AECs. Recombinant human galectin-3 also induced EMT and stemness-associated changes in the AECs, and GB1107, a galectin-3 inhibitor, ameliorated these changes. Further, CSE-induced intracellular ROS enabled an increase in RUNX-2 and galectin-3 expression, which were reversed by n-acetyl-cysteine.

SIGNIFICANCE

These results provide a novel mechanistic insight into CSE-induced EMT via RUNX-2/galectin-3 axis mediated through ROS, which promoted EMT-associated changes, including invasion, migration, and stemness in AECs, which could be implicated in CS-induced lung cancer progression.

The Role of the Acetylcholine System in Common Respiratory Diseases and COVID-19

As an indispensable component in human beings, the acetylcholine system regulates multiple physiological processes not only in neuronal tissues but also in nonneuronal tissues. However, since the concept of the "Nonneuronal cholinergic system (NNCS)" has been proposed, the role of the acetylcholine system in nonneuronal tissues has received increasing attention. A growing body of research shows that the acetylcholine system also participates in modulating inflammatory responses, regulating contraction and mucus secretion of respiratory tracts, and influencing the metastasis and invasion of lung cancer. In addition, the susceptibility and severity of respiratory tract infections caused by pathogens such as Mycobacterium Tuberculosis and the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) can also correlate with the regulation of the acetylcholine system. In this review, we summarized the major roles of the acetylcholine system in respiratory diseases. Despite existing achievements in the field of the acetylcholine system, we hope that more in-depth investigations on this topic will be conducted to unearth more possible pharmaceutical applications for the treatment of diverse respiratory diseases.

Direct adsorption sampling and ambient mass spectrometry analysis of tobacco smoke with porous paper strips

Chemical analysis of atmospheric aerosols by conventional analytical methods is usually required to perform complicated and time-consuming sample preparation processes. In recent decades, ambient ionization mass spectrometry (AI-MS) methods have been proven to be simple, rapid, and effective analytical tools for direct analysis of various complex samples. In this work, we applied porous paper filters for direct adsorptive sampling of tobacco smoke, and then the sampled paper filters were performed the emitters of the paper spray ionization (PSI) device. An auto-sampling device was made to control the generation and collection of tobacco smoke. Nicotine, the typical compound of tobacco smoke, was used to optimize the key conditions of auto-sampling. Moreover, different types of tobacco smoke were also compared with multivariate variable analysis, and the makers of tobacco smoke from different sources of tobacco smoke were investigated. By using this method, direct sampling and analysis of a single tobacco sample can be completed within minutes. Overall, our results show that PSI-MS is a powerful tool that integrates collection, extraction, ionization, and identification analytes in smoke.

Effects of smoking on the tissue regeneration-associated functions of human endometrial stem cells via a novel target gene SERPINB2

BACKGROUND

Smokers directly inhale mainstream cigarette smoke, which contains numerous known and potential toxic substances, and thus, smoking is expected to have broad harmful effects that cause tissue injury and dysfunction. Interestingly, many studies have suggested that the recent decline in female fertility and increased rate of spontaneous abortion could be associated with increased smoking rates. Indeed, women that smoked for 10 years or more were reported to have a ~ 20% higher infertility rate than women that had never smoked. However, the reasons for the underlying harmful aspects of smoking on female fertility remain a matter of debate. Importantly, a previous study revealed that resident endometrial stem cell deficiency significantly limits the cyclic regeneration potential of endometrium, which, in turn, decreases successful pregnancy outcomes. In this context, we postulated that exposure to mainstream cigarette smoke extracts might decrease female fertility by inhibiting the functions of resident endometrial stem cells.

METHODS

We investigated whether cigarette mainstream smoke exposure directly inhibits various tissue regeneration-associated functions of endometrial stem cells, such as self-renewal, migration, pluripotency, and differentiation capacity in vitro. Next, we determined whether SERPINB2 mediates cigarette smoke-induced suppressive effects on various tissue regeneration-associated functions by depleting SERPINB2 expression with specific shRNA targeting SERPINB2. Mice were injected intraperitoneally with low (0.5 mg/kg) or high (1 mg/kg) doses of cigarette smoke extract (10 times for two weeks), and endometrial stem cells were then isolated from mice uterine tissues.

RESULTS

We found that exposure to cigarette smoke extracts remarkably suppressed various tissue regeneration-associated functions of endometrial stem cells, such as self-renewal, migration, multilineage differentiation ability, and pluripotency in vitro and in vivo by activating the SERPINB2 gene. Indeed, cigarette smoke-induced inhibitory effects on various endometrial stem cell functions were significantly abolished by SERPINB2 knockdown.

CONCLUSIONS

These findings provide valuable information on the harmful effects of cigarette smoking on resident endometrial stem cells and hopefully will facilitate the developments of promising therapeutic strategies for subfertile or infertile women that smoke cigarettes.

The prevalence and predictors of cardiovascular diseases in Kherameh cohort study: a population-based study on 10,663 people in southern Iran

BACKGROUND

The prevalence of cardiovascular disease (CVD) is rapidly increasing in the world. The present study aimed to assess the prevalence and Predictors factors of CVD based on the data of Kherameh cohort study.

METHODS

The present cross-sectional, analytical study was done based on the data of Kherameh cohort study, as a branch of the Prospective Epidemiological Studies in Iran (PERSIAN). The participants consisted of 10,663 people aged 40-70 years. CVD was defined as suffering from ischemic heart diseases including heart failure, angina, and myocardial infarction. Logistic regression was used to model and predict the factors related to CVD. Additionally, the age-standardized prevalence rate (ASPR) of CVD was determined using the standard Asian population.

RESULTS

The ASPR of CVD was 10.39% in males (95% CI 10.2-10.6%) and 10.21% in females (95% CI 9.9-10.4%). The prevalence of CVD was higher among the individuals with high blood pressure (58.3%, p < 0.001) as well as among those who smoked (28.3%, p = 0.018), used opium (18.2%, p = 0.039), had high triglyceride levels (31.6%, p = 0.011), were overweight and obese (66.2%, p < 0.001), were unmarried (83.9%, p < 0.001), were illiterate (64.2%, p < 0.001), were unemployed (60.9%, p < 0.001), and suffered from diabetes mellitus (28.1%, p < 0.001). The results of multivariable logistic regression analysis showed that the odds of having CVD was 2.25 times higher among the individuals aged 50-60 years compared to those aged 40-50 years, 1.66 folds higher in opium users than in non-opium users, 1.37 times higher in smokers compared to non-smokers, 2.03 folds higher in regular users of sleeping pills than in non-consumers, and 4.02 times higher in hypertensive individuals than in normotensive ones.

CONCLUSION

The prevalence of CVD was found to be relatively higher in Kherameh (southern Iran) compared to other places. Moreover, old age, obesity, taking sleeping pills, hypertension, drug use, and chronic obstructive pulmonary disease had the highest odds ratios of CVD.

Determination of Free Solanesol Levels in Cigarette Filters by Liquid Chromatography-Mass Spectrometry

Solanesol, a naturally occurring constituent of tobacco, has been utilized as a good marker for environmental tobacco smoke particulate and as a noninvasive predictor of mainstream cigarette smoke tar and nicotine intake under naturalistic smoking conditions. A fast and accurate method for measuring free solanesol to assess tobacco smoke exposure is highly desirable. We have developed and validated a new environmentally friendly, high-throughput method for measuring solanesol content in discarded cigarette filter butts. The solanesol deposited in the used filters can be correlated with mainstream smoke deliveries of nicotine and total particle matter to estimate constituent delivery to smokers. A portion of filter material is removed from cigarette butts after machine smoking, spiked with internal standard solution, extracted and quantitatively analyzed using reverse-phase liquid chromatography coupled to a triple-quadrupole mass spectrometer. The new method incorporates a 48-well plate format for automated sample preparation that reduces sample preparation time and solvent use and increases sample throughput 10-fold compared to our previous method. Accuracy and precision were evaluated by spiking known amounts of solanesol on both clean and smoked cigarette butts. Recoveries exceeded 93% at both low and high spiking levels. Linear solanesol calibration curves ranged from 1.9 to 367 µg/butt with a 0.05 µg/butt limit of detection.

Addiction and human male fertility: A systematic review and a critical appraisal

BACKGROUND

Addiction is a global problem that has many negative consequences on human health as well as the quality of life.

OBJECTIVES

This review aimed to assess the effect of addiction on human male fertility.

METHODS

A systematic review was conducted on various electronic sites.

RESULTS

The initial literature search identified a total of 5239 articles in all searched databases. After removing duplicates and application of inclusion/exclusion criteria,177 were potential articles, 112 were omitted because no direct relevance was encountered. Finally, 65 studies were retained for review. They were classified according to the type of addiction into; opioids and cannabinoids (18 articles), alcohol (7 articles), cocaine (2 articles), Androgenic Anabolic steroids AAS (15 articles), tobacco (10 articles) and caffeine (13 articles). Most of these recruited articles demonstrated a negative impact of the addressed substance on male fertility with variable levels of evidence.

CONCLUSIONS

It was concluded that addiction harms human male fertility that should be put into consideration. More future studies are needed after a proper methodological and statistical approach, including logistic regression analysis, to predict the effect of a specific substance on human male fertility. This article is protected by copyright. All rights reserved.

Probe on Various Experimental Cigarette Smoke Subjection Structure

Different methods of subjection to smoke from experimental cigarettes are essential for understanding tobacco smoke. The major toxicants found in tobacco are acetaldehyde, acetone, acrolein, acrylonitrile, ammonia, benzene, cadmium, catechol, chromium, cyanide hydrogen, arsenic, nickel, nitric oxide, nicotine last but not least, mono-oxide gases. While experts say, cigarette smoke contains more than 4000 different compounds. These are substantially toxic and can destroy cells, and many of them are carcinogenic. Various smoke-exposure devices are used for in-vitro tobacco smoke generation, dilution, and distribution. Such devices are used widely by well-known manufacturers or can be tailor-made setups. We can set up different in-vitro models to better treat smoke-related diseases using these subjection structures. The fundamental goal will be to build a tobacco-free society of available subjection systems. Some have been identified and established as biological endpoints in some published scientific literature. In the scientific field, many new technologies are coming out and showing their presence. There are many systems of exposure to cigarette smoke in vitro which offer a more flexible approach to the challenges of exposure to tobacco smoke. This review covers some topics such as the description of available new subjection structures and reviews their work, setting up and application for Scenarios of in-vitro treatment. The benefits and disadvantages of both subjection mechanisms and the similarities between the setups and the data extracted from these structures. Measuring the smoke dose is also discussed here as an important field of research, particularly in the preclinical phase. Keywords: Cigarette smoke; Cigarette Subjection Structures; Cigarette Subjection Mechanisms; Cigarette Subjection Advantages; Cigarette Subjection Use; Cigarette Subjection Modern advancements.

A Novel Tri-Layer Cellulose-Based Membrane for the Capture and Analysis of Mainstream Smoke of Tobacco

Efficient capture of particulate matter in the smoke mainstream using low-cost filter pads is important for cost-effective analysis of mainstream smoke. The Cambridge filter pad (CFP) is the standard material for the collection of particulate matter in the mainstream. In this work, we report a low-cost alternative to CFP, which is composed of a cellulose acetate fiber (CAF) interlayer and two cotton fiber (CF) layers on both sides. The CF/CAF/CF filter exhibited high affinity toward typical tobacco additives such as glycerol and glycerol triacetate. In addition, the CF/CAF/CF filter had a favorable porous structure for the trapping of particulate matter. Due to these beneficial features, the CF/CAF/CF filter exhibited improved particulate matter trapping performance. These results suggest that the as-developed CF/CAF/CF filter could be a low-cost alternative to CFP.

Application of ToxTracker for the toxicological assessment of tobacco and nicotine delivery products

Consumer demands and innovation have led to an increasingly diverse range of nicotine delivery systems, driven by a desire to reduce risk associated with traditional combustible cigarettes. This speed of change provides a mandate for rapid new product assessment. We have used the validated technology ToxTracker®, to assess biomarkers of DNA damage, protein misfolding, oxidative and cellular stress, across the categories of cigarette (1R6F), tobacco heating product (THP 1.4) and electronic cigarette (ePen 3). In addition, we compared the commonly used test matrices for tobacco and nicotine products; whole aerosol aqueous extracts (AqE) and gas vapour phase (GVP), determining their suitability across the product categories. We demonstrated a significant reduction in oxidative stress and cytotoxicity for THP 1.4 over cigarette, further reduced for ePen 3, when assessed by both dilution and nicotine dosimetry. We also identified that while the extraction matrices AqE and GVP from combustible products were equivalent in the induced responses, this was not true of the other category examples, moreover THP 1.4 GVP demonstrates a >50 % reduction in both toxicity and cytotoxicity endpoints over AqE. This indicates that unlike cigarette, the active components or toxicants for THP and electronic cigarette are associated with the aerosol fraction of these categories.

NMR Spectroscopy Identifies Chemicals in Cigarette Smoke Condensate That Impair Skeletal Muscle Mitochondrial Function

Tobacco smoke-related diseases such as chronic obstructive pulmonary disease (COPD) are associated with high healthcare burden and mortality rates. Many COPD patients were reported to have muscle atrophy and weakness, with several studies suggesting intrinsic muscle mitochondrial impairment as a possible driver of this phenotype. Whereas much information has been learned about muscle pathology once a patient has COPD, little is known about how active tobacco smoking might impact skeletal muscle physiology or mitochondrial health. In this study, we examined the acute effects of cigarette smoke condensate (CSC) on muscle mitochondrial function and hypothesized that toxic chemicals present in CSC would impair mitochondrial respiratory function. Consistent with this hypothesis, we found that acute exposure of muscle mitochondria to CSC caused a dose-dependent decrease in skeletal muscle mitochondrial respiratory capacity. Next, we applied an analytical nuclear magnetic resonance (NMR)-based approach to identify 49 water-soluble and 12 lipid-soluble chemicals with high abundance in CSC. By using a chemical screening approach in the Seahorse XF96 analyzer, several CSC-chemicals, including nicotine, o-Cresol, phenylacetate, and decanoic acid, were found to impair ADP-stimulated respiration in murine muscle mitochondrial isolates significantly. Further to this, several chemicals, including nicotine, o-Cresol, quinoline, propylene glycol, myo-inositol, nitrosodimethylamine, niacinamide, decanoic acid, acrylonitrile, 2-naphthylamine, and arsenic acid, were found to significantly decrease the acceptor control ratio, an index of mitochondrial coupling efficiency.

Common cosmetic compounds can reduce air pollution-induced oxidative stress and pro-inflammatory response in the skin

Introduction: Constantly increasing air pollution (AP) poses a concern negatively affecting our health including the skin. A typical manifestation of the skin damage induced by AP is its premature aging, irritation, skin barrier impairment, pigmentation disorders and development or exacerbation of various skin diseases. For these reasons, it is crucial to protect the skin from the negative effects of AP. In this study we evaluated the ability of some compounds commonly used in dermatological or cosmetic preparations with various biological activities to reduce AP-induced skin damage. Methods: We established a new experimental model using porcine skin explants exposed to cigarette smoke (CS) where we determined the level of reactive oxygen species (ROS) in the stratum corneum, skin barrier lipids peroxidation and gene expression of the pro-inflammatory cytokine IL-6 in the epidermis. We then tested several polysaccharides and their derivatives such as sodium hyaluronate (SH) of different molecular weights (MW, 1,6 MDa, 300 kDa, 15 kDa, 5 kDa), yeast glucomannan, schizophyllan and carboxymethyl β-glucan, a vitamin C derivative sodium ascorbyl phosphate, niacinamide and D-panthenol for their ability to prevent CS-induced skin damage. For the evaluation and comparison of their mechanism of action, film-forming effect was determined by TEWL and gloss measurements and the antioxidant properties were assessed by DPPH assay. Results: In the skin samples exposed to CS we observed significant negative changes such as the presence of large amount of ROS in the stratum corneum, a high level of skin barrier lipids peroxidation and upregulated IL6 gene expression. Pretreatment of the skin samples with all the tested substances significantly prevented CS-induced skin damage. The most effective was high MW SH probably due to its best film-forming effect and sodium ascorbyl phosphate with the best antioxidant properties. Conclusion: AP leads to a significant skin damage which can be effectively prevented by using some conventional cosmetic and dermatological ingredients with various mechanisms of action.

Acid-Catalyzed Isomerization of Carbonyls-2,4- dinitrophenylhydrazone in Mainstream Smoke of Heat-Not-Burn Tobacco Product for HPLC Analysis

Carbonyls (such as acrolein, acetaldehyde, and formaldehyde) are the critical type of carcinogens and toxicants contained within the heat-not-burn (HNB) tobacco products. Using HNB products can have negative effects on human health; therefore, it is important to measure carbonyl contents within the HNB mainstream smoke. Typically, the 2,4-dinitrophenylhydrazine (DNPH) approach involves forming the 2,4-dinitrophenylhydrazone derivatives, which is the most extensively adopted approach to qualitatively and quantitatively analyze carbonyl compounds. However, the approach can result in analytical error because 2,4-dinitrophenylhydrazones contains the E-stereoisomer as well as the Z-stereoisomer. Only an E-isomers exists in the purified carbonyls-2,4-dinitrophenylhydrazone, but when acid is added, the E-isomer and Z-isomer can be observed. For propionaldehyde-, acetaldehyde-, crotonaldehyde-, acrolein-, and 2-butanone-2,4-dinitrophenylhydrazones, their equilibrium Z/E isomer ratios are 0.143, 0.309, 0.093, 0.028, and 0.154. In the case of adding trace water into hydrazone derivatives dissolved within the acetonitrile solution, the derivative contents decrease, whereas the free DNPH content increases. Therefore, catalytic acid should be added in the low content. To determine carbonyls-2,4-dinitrophenylhydrazones through HPLC, the optimal approach is adding phosphoric acid into the samples and the standard reference solution to form the 0.02–1.0% acid solution.

A Literature Review and Framework Proposal for Halitosis Assessment in Cigarette Smokers and Alternative Nicotine-Delivery Products Users

Halitosis is a health condition which counts cigarette smoking (CS) among its major risk factors. Cigarette smoke can cause an imbalance in the oral bacterial community, leading to several oral diseases and conditions, including intraoral halitosis. Although the best approach to decrease smoking-related health risks is quitting smoking, this is not feasible for many smokers. Switching to potentially reduced-risk products, like electronic vapor products (EVP) or heated tobacco products (HTP), may help improve the conditions associated with CS. To date, there have been few systematic studies on the effects of CS on halitosis and none have assessed the effects of EVP and HTP use. Self-assessment studies have shown large limitations owing to the lack of reliability in the participants' judgment. This has compelled the scientific community to develop a strategy for meaningful assessment of these new products in comparison with cigarettes. Here, we compiled a review of the existing literature on CS and halitosis and propose a 3-layer approach that combines the use of the most advanced breath analysis techniques and multi-omics analysis to define the interactions between oral bacterial species and their role in halitosis both in vitro and in vivo. Such an approach will allow us to compare the effects of different nicotine-delivery products on oral bacteria and quantify their impact on halitosis. Defining the impact of alternative nicotine-delivery products on intraoral halitosis and its associated bacteria will help the scientific community advance a step further toward understanding the safety of these products and their potentiall risks for consumers.

The combined chemical and mechanical modifications of cigarette: a novel methodology to reduce harmful effects

Without hindering the taste, making a cigarette less harmful by reducing the percentage of toxic and carcinogenic compounds in the smoke of the cigarette is a challenging task for the current generation of researchers. In the current work, by implementing mechanical, chemical and combined modification techniques, the above stated is tried to mitigate. In addition to the above, the optimum suction pressure, burning time and the number of puffing are also determined. Mechanical modification technique considers filter to cigarette ratio and filter design as the controlling parameters. The mathematical calculation reveals that puffing should stop when the cigarette length reaches 0.15 times of its original length. Furthermore, it is also identified that the concentrations of suspended solids and droplets in the smoke decrease significantly (separation efficiency = 56.81%) if the cigarette to filter ratio is maintained at 2.32. In case of chemical modification, by using various types of adsorbents such as charcoal and Zeolite 13X, the harmful effects are further reduced. These processes depict significant reduction in harmful effect (separation efficiency up to 62.1%) by showing the decrement in the suspended solids and droplets in the smoke due to the adsorption on the active sites of adsorbents. In case of combined modification, the achieved separation efficiency is 66.51%. For the experimentation, an experimental setup fitted with artificial lungs was used.

Genetic and epigenetic regulation of the NRF2-KEAP1 pathway in human lung cancer

Electrophilic and oxidative stress is caused when homeostatic mechanisms are disrupted. A major defense mechanism involves the activation of the nuclear factor erythroid 2-related factor 2 (NRF2) transcription factor encoded by the NFE2L2 gene, which can accelerate the detoxification of electrophilic carcinogens and prevent cancer and on the other hand in certain exposure contexts may exacerbate the carcinogenic process. NRF2-target genes activated under these conditions can be used as biomarkers of stress signalling, while activation of NRF2 can also reveal the epigenetic mechanisms that modulate NFE2L2 expression. Epigenetic mechanisms that regulate NFE2L2 and the gene for its adaptor protein KEAP1 include DNA methylation, histone modifications and microRNA. Understanding the activation of the NRF2-KEAP1 signalling pathway in human lung cancer, its epigenetic regulation and its role in oncogenesis is the subject of this review.

Impact of aerosols on liver xenobiotic metabolism: A comparison of two methods of exposure

Assessment of aerosols effects on liver CYP function generally involves aqueous fractions (AF). Although easy and efficient, this method has not been optimized recently or comparatively assessed against other aerosol exposure methods. Here, we comparatively evaluated the effects of the AFs of cigarette smoke (CS) and Tobacco Heating System (THS) aerosols on CYP activity in liver spheroids. We then used these data to develop a physiological aerosol exposure system combining a multi-organs-on-a-chip, 3D lung tissues, liver spheroids, and a direct aerosol exposure system. Liver spheroids incubated with CS AF showed a dose-dependent increase in CYP1A1/1B1, CYP1A2, and CYP2B6 activity and a dose-dependent decrease in CYP2C9, CYP2D6, and CYP3A4 activity relative to untreated tissues. In our physiological exposure system, repeated CS exposure of the bronchial tissues also caused CYP1A1/1B1 and CYP1A2 induction in the bronchial tissues and liver spheroids; but the spheroids showed an increase in CYP3A4 activity and no effect on CYP2C9 or CYP2D6 activity relative to air-exposed tissues, which resembles the results reported in smokers. THS aerosol did not affect CYP activity in bronchial or liver tissues, even at 4 times higher concentrations than CS. In conclusion, our system allows us to physiologically test the effects of CS or other aerosols on lung and liver tissues cultured in the same chip circuit, thus delivering more in vivo like data.

Effects of cigarette smoking on the growth of Streptococcus mutans biofilms: An in vitro study

The increased incidence of dental caries by cigarette smoking (CS) has been widely reported in epidemiological studies, but the relationship between CS and cariogenic biofilm growth has been rarely studied. This study aims to investigate the effects of CS exposure on the growth and virulence of Streptococcus mutans biofilms (S. mutans). Briefly, S. mutans biofilms were formed on saliva-coated hydroxyapatite disks, which were exposed to CS 1, 3, and 6 times per day, respectively. In addition, S. mutans biofilms without CS exposure were considered as the control group. Acidogenicity, dry weight, colony-forming units (CFUs), water-soluble/insoluble extracellular polysaccharides (EPSs), and intracellular polysaccharides (IPSs) were analyzed and confocal laser scanning microscopy (CLSM) images of 74-h-old S. mutans biofilms were obtained. The lowest accumulation of biofilms and EPSs were detected in the 6 times/day CS exposure group compared with those of the control group and other CS exposure groups in 74-h-old S. mutans biofilms. CLSM also revealed the lowest bacterial count (live and dead cells) and EPSs biovolume in the six times/day CS exposure group in 74-h-old S. mutans biofilms. CS exposure inhibited the growth of S. mutans biofilm in vitro study, the anti-cariogenic biofilm formation was enhanced with a dose (frequency)-dependent at which frequency has more influence in the present findings.

Transcriptional Response of Mycobacterium tuberculosis to Cigarette Smoke Condensate

Smoking is known to be an added risk factor for tuberculosis (TB), with nearly a quarter of the TB cases attributed to cigarette smokers in the 22 countries with the highest TB burden. Many studies have indicated a link between risk of active TB and cigarette smoke. Smoking is also known to significantly decrease TB cure and treatment completion rate and increase mortality rates. Cigarette smoke contains thousands of volatile compounds including carcinogens, toxins, reactive solids, and oxidants in both particulate and gaseous phase. Yet, to date, limited studies have analyzed the impact of cigarette smoke components on Mycobacterium tuberculosis (Mtb), the causative agent of TB. Here we report the impact of cigarette smoke condensate (CSC) on survival, mutation frequency, and gene expression of Mtb in vitro. We show that exposure of virulent Mtb to cigarette smoke increases the mutation frequency of the pathogen and strongly induces the expression of the regulon controlled by SigH—a global transcriptional regulator of oxidative stress. SigH has previously been shown to be required for Mtb to respond to oxidative stress, survival, and granuloma formation in vivo. A high-SigH expression phenotype is known to be associated with greater virulence of Mtb. In patients with pulmonary TB who smoke, these changes may therefore play an important, yet unexplored, role in the treatment efficacy by potentially enhancing the virulence of tubercle bacilli.

Modifying effects of menthol against benzo(a)pyrene-induced forestomach carcinogenesis in female Swiss mice

Benzo(a)pyrene (BaP) is a polycyclic aromatic hydrocarbon widespread in the environment and closely associated to tobacco use, which is an important risk factor for highly incident stomach cancer. Menthol, a monoterpene extracted from Mentha genus species, has multiple biological properties, including anti-inflammatory and gastroprotective properties, but its effects on carcinogenesis are still to be fully understood. Thus, we evaluated the modifying effects of Ment against BaP-induced forestomach carcinogenesis. Female Swiss mice received BaP by intragastrical (i.g.) administration (50 mg/kg of body weight [b wt], 2×/week), from weeks 1-5 weeks. Concomitantly, mice received Menthol at 25 (Ment25) or 50 (Ment50) mg/kg b wt (i.g, 3×/week). Animals were euthanized at weeks 5 (n = 5 mice/group) or 30 (n = 10 mice/group). At week 5, both Ment doses reduced peripheral leukocyte blood genotoxicity 4 h after the last BaP administration, but only Ment50 attenuated this biomarker 8 h after the last BaP administration. In accordance to these findings, both Ment interventions attenuated BaP-induced increase in the percentage of H2A.X-positive forestomach epithelial cells. Moreover, Ment50 reduced cell proliferation and apoptosis (i.e., Ki-67 and caspase-3, respectively) in forestomach epithelium but exerted no significant effects on NFκB, and Nrf2 protein levels. At week 30, Ment50 reduced by ~55% the incidence of BaP-induced forestomach diffuse hyperplasia and multiplicity of forestomach tumors (squamous cell papillomas and carcinomas). Our findings indicate that Ment50, administered during initiation phase, attenuates forestomach carcinogenesis by reducing early genotoxicity, cell proliferation, and apoptosis induced by BaP.

Comparative study of the effects of cigarette smoke versus next generation tobacco and nicotine product extracts on endothelial function

Tobacco smoking and hemodynamic forces are key stimuli for the development of endothelial dysfunction. As an alternative to smoking, next generation tobacco and nicotine products (NGP) are now widely used. However, little is known about their potential pro-inflammatory and atherogenic effects on the endothelium. In this study, we analyzed key parameters of endothelial function after exposure to aqueous smoke extracts (AqE) of a heated tobacco product (HTP), an electronic cigarette (e-cig), a conventional cigarette (3R4F) and pure nicotine. All experiments were performed under atheroprotective high laminar or atherogenic low flow with primary human endothelial cells. Treatment with 3R4F, but not alternative smoking products, reduced endothelial cell viability and wound healing capability via the PI3K/AKT/eNOS(NOS3) pathway. Laminar flow delayed detrimental effects on cell viability by 3R4F treatment. 3R4F stimulation led to activation of NRF2 antioxidant defense system at nicotine concentrations ≥0.56 μg/ml and increased expression of its target genes HMOX1 and NQO1. Treatment with HTP revealed an induction of HMOX1 and NQO1 at dosages with ≥1.68 μg/ml nicotine, whereas e-cig and nicotine exposure had no impact. Analyses of pro-inflammatory genes revealed an increased ICAM1 expression under 3R4F treatment. 3R4F reduced VCAM1 expression in a dose-dependent manner; HTP treatment had similar but milder effects; e-cig and nicotine treatment had no impact. SELE expression was induced by 3R4F under static conditions. High laminar flow prevented this upregulation. Stimulation with laminar flow led to downregulation of CCL2 (MCP-1). From this downregulated level, only 3R4F increased CCL2 expression at higher concentrations. Finally, under static conditions, all components increased adhesion of monocytes to endothelial cells. Interestingly, only stimulation with 3R4F revealed increased monocyte adhesion under atherosclerosis-prone low flow. In conclusion, all product categories activated anti-oxidative or pro-inflammatory patterns. NGP responses were typically lower than in 3R4F exposed cells. Also, 3R4F stimulation led to an impaired endothelial wound healing and induced a pro-inflammatory phenotype compared to NGP treatment.

(-)-Epicatechin ameliorates cigarette smoke-induced lung inflammation via inhibiting ROS/NLRP3 inflammasome pathway in rats with COPD

Chronic obstructive pulmonary disease (COPD) with increased morbidity and mortality is a worldwide healthcare challenge closely associated with cigarette smoking (CS). Currently, there is no effective therapeutic strategy to control inflammation in COPD patients. The present study tested the protective effects of (-)-Epicatechin (EC), a type of flavonoid, on CS-induced COPD and the underlying mechanism. Also, EC repressed the production of reactive oxygen species (ROS) and improved human bronchial epithelial cell viability after cigarette smoke extract (CSE) treatment. Further studies demonstrated that EC promotes ubiquitin-mediated Keap1 degradation by upregulating tripartite motif-containing protein 25 (TRIM25) expression and enhances the nuclear localization of Nrf2 protein. Also, EC dramatically inhibits the activation of NLRP3 inflammasome and reduces the CSE-induced pyroptosis, as indicated by decreasing lactate dehydrogenase release and the number of caspase-1-positive cells. Importantly, Nrf2 knockdown reversed the protective effect of EC on human bronchial epithelial cells, at least partially. Consistent with the results in vitro, EC inhibits the activation of NLRP3 inflammasome and relieves the CS-induced lung inflammation, as evident from decreased interleukin (IL)-1β and IL-18 secretion in a COPD rat model. In conclusion, this study revealed the protective effect of EC on experimental COPD rats and elucidated the mechanism of EC promoting Nrf2 activity, which might provide a novel therapeutic strategy for COPD.

Smoking induces sex-specific changes in the small airway proteome

Introduction

Cigarette smoke triggers many cellular and signaling responses in the lung and the resulting inflammation plays a central role in smoke-related lung diseases, such as COPD. We explored the effects of smoking on the small airway proteome in samples obtained by collection of exhaled particles with the aim to identify specific proteins dysregulated by smoking.

Methods

Exhaled particles were obtained from 38 current smokers, 47 former smokers and 22 healthy controls with the PExA method. 120 ng of sample was collected from individual subjects and analyzed with the SOMAscan proteomics platform. General linear model-based statistics were performed.

Results

Two hundred and three proteins were detected in at least half of 107 total samples. Active smoking exerted a significant impact on the protein composition of respiratory tract lining fluid (RTLF), with 81 proteins altered in current smokers compared to never smokers (p < 0.05, q < 0.124). Among the proteins most clearly discriminating between current and never smokers were sRAGE, FSTL3, SPOCK2 and protein S, all of them being less abundant in current smokers. Analysis stratified for sex unveiled sex differences with more pronounced proteomic alterations due to active smoking in females than males. Proteins whose abundance was altered by active smoking in women were to a larger extent related to the complement system. The small airway protein profile of former smokers appeared to be more similar to that observed in never smokers.

Conclusions

The study shows that smoking has a strong impact on protein expression in the small airways, and that smoking affects men and women differently, suggesting PExA sampling combined with high sensitivity protein analysis offers a promising platform for early detection of COPD and identification of novel COPD drug targets.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-021-01825-6.

Anti-pollution effects of two antioxidants and a chelator-Ex vivo electron spin resonance and in vivo cigarette smoke model assessments in human skin

BACKGROUND

Skin damage arising from pollutants in gaseous and particulate matter forms is mainly mediated by oxidative stress. The pollutants directly or indirectly generate free radicals on and in the skin, leading, for example, to MMP up-regulation and damage of collagen fibers. Antioxidants and chelators are used in anti-pollution cosmetics to reduce the harmful effects of free radical generation.

MATERIALS AND METHODS

We investigated the efficacy of two antioxidants and one chelator in an anti-pollution cigarette smoke model. Free radical generation was measured directly after UV and cigarette smoke exposure ex vivo on pig skin (slaughterhouse waste), by use of Electron Spin Resonance (ESR). Effects of cigarette smoke were compared to those of Urban Dust (NIST-standard). ESR was also used to measure the copper chelation activity of the test products. Following cigarette smoke application in vivo, two markers of lipid peroxidation malondialdehyde (MDA), and squalene monohydroperoxide (SQOOH), were measured from swab solutions taken from the smoke-exposed skin sites.

RESULTS

EDTA generated no effect and the non-chelator antioxidant Tocopherol only small antioxidant effects after exposed to cigarette smoke ex vivo as well as in vivo. Only the hydrophilic phenylethanoid H1 showed significant effects. A clear reduction of free radicals ex vivo and further a significant reduction of in vivo lipid peroxide formation was measured.

CONCLUSION

The cigarette smoke model is an ideal method for in vivo assessment of anti-pollution efficacy of topical products with close relation to the real situation of subjects exposed to urban pollution. Further research is required to better understand the role of chelators in anti-pollution cosmetics.

Cigarette smoke exposure and alveolar macrophages: mechanisms for lung disease

Cigarette smoking is the leading cause of preventable death worldwide. It causes chronic lung disease and predisposes individuals to acute lung injury and pulmonary infection. Alveolar macrophages are sentinel cells strategically positioned in the interface between the airway lumen and the alveolar spaces. These are the most abundant immune cells and are the first line of defence against inhaled particulates and pathogens. Recently, there has been a better understanding about the ontogeny, phenotype and function of alveolar macrophages and their role, not only in phagocytosis, but also in initiating and resolving immune response. Many of the functions of the alveolar macrophage have been shown to be dysregulated following exposure to cigarette smoke. While the mechanisms for these changes remain poorly understood, they are important in the understanding of cigarette smoking-induced lung disease. We review the mechanisms by which smoking influences alveolar macrophage: (1) recruitment, (2) phenotype, (3) immune function (bacterial killing, phagocytosis, proteinase/anti-proteinase release and reactive oxygen species production) and (4) homeostasis (surfactant/lipid processing, iron homeostasis and efferocytosis). Further understanding of the mechanisms of cigarette smoking on alveolar macrophages and other lung monocyte/macrophage populations may allow novel ways of restoring cellular function in those patients who have stopped smoking in order to reduce the risk of subsequent infection or further lung injury.

The Discrepancy between Clove and Non-Clove Cigarette Smoke-Promoted Candida albicans Biofilm Formation with Precoating RNA-aptamer

This study explores the influence of precoating aptamer (Ca-apt1) on C. albicans viability while the fungus was growing in the presence of exposing condensed cigarette smoke (CSC), prepared from clove (CCSC) and non-clove (NCSC) cigarettes, for 48 h. Using qPCR, we found that mRNA expression of adhesion-associated genes ( ALS3 and HWP1) was impaired by precoating C. albicans yeast cells with the aptamer. Conversely, the gene transcription was upregulated when aptamer-uncoated yeast was pre-treated with either CSC. In addition, by analysing the result of MTT ([3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide] assay, we found that the presence of added CCSC or NCSC in growth medium for 48 h was significantly enhanced C. albicans biofilm development. However, the presence of precoated aptamer was significantly impaired biofilm development accelerated by the NCSC. The inhibitory effect of the Ca-apt1 was not dependent on the precoated aptamer (1ng/μL and 10 ng/μL). Interestingly, we noted that the enhancer effect of treated CCSC was no longer effective when the yeast had been precoated with 10 ng/μL aptamer tested. Additionally, light microscopy analysis revealed that precoating aptamer alleviates morphological changes of C. albicans (from yeast to hypha formation) that are enhanced by adding CCSC or NCSC in the growth medium.

In conclusion, these results suggest that administration on Ca-ap1 exhibits a significant protective effect on CSC-induced biofilm formation by C. albicans.

210Pb and 210Po concentration levels in tobacco products and resulting radiation dose for Egyptian smokers

The activity concentrations of ²¹⁰Pb and ²¹⁰Po in the most popular cigarettes and moassel tobacco brands consumed in Egypt were determined by the spontaneous deposition method using alpha spectrometry. It turned out that the activity concentration of ²¹⁰Po was higher than that of ²¹⁰Pb in all tobacco brands. Higher activity concentrations for both ²¹⁰Pb and ²¹⁰Po were found in cigarette than in moassel tobacco. The average activity concentrations of ²¹⁰Pb and ²¹⁰Po in cigarette tobacco were 11.79 ± 1.67 and 15.00 ± 1.83 mBq cig^-1, respectively, whereas in moassel tobacco the values were 7.08 ± 1.91 and 9.12 ± 1.12 mBq g^-1, respectively. The daily activities inhaled in the lung of a smoker and the inhalation effective doses due to cigarette and shisha smoking were calculated. The results revealed that the total ²¹⁰Pb and ²¹⁰Po daily activities inhaled and the total annual inhalation effective doses due to shisha smoking were two times greater than the corresponding values due to cigarette smoking. Also, the results indicated that the annual effective doses from inhalation of ²¹⁰Pb and ²¹⁰Po due to smoking 20 cigarettes per day are 14 and 16 times greater than the annual ingestion doses from the diet, respectively. In contrast, the annual effective doses from inhalation of ²¹⁰Pb and ²¹⁰Po due to shisha smoking (27 g moassel tobacco per day) are 26 and 33 times greater than the annual ingestion doses from the diet, respectively.

Early Chemistry of Nicotine Degradation in Heat-Not-Burn Smoking Devices and Conventional Cigarettes: Implications for Users and Second- and Third-Hand Smokers

Nicotine exposure results in health risks not only for smokers but also for second- and third-hand smokers. Unraveling nicotine's degradation mechanism and the harmful chemicals that are produced under different conditions is vital to assess exposure risks. We performed a theoretical study to describe the early chemistry of nicotine degradation by investigating two important reactions that nicotine can undergo: hydrogen abstraction by hydroxyl radicals and unimolecular dissociation. The former contributes to the control of the degradation mechanism below 800 K due to a non-Arrhenius kinetics, which implies an enhancement of reactivity as temperature decreases. The latter becomes important at higher temperatures due to its larger activation energy. This change in the degradation mechanism is expected to affect the composition of vapors inhaled by smokers and room occupants. Conventional cigarettes, which operate at temperatures higher than 1000 K, are more prone to yield harmful pyridinyl radicals via nicotine dissociation, while nicotine in electronic cigarettes and vaporizers, with operating temperatures below 600 K, will be more likely degraded by hydroxyl radicals, resulting in a vapor with a different composition. Although low-temperature nicotine delivery devices have been claimed to be less harmful due to their nonburning operating conditions, the non-Arrhenius kinetics that we observed for the degradation mechanism below 873 K suggests that nicotine degradation may be more rapidly initiated as temperature is reduced, indicating that these devices may be more harmful than it is commonly assumed.

Erythropoetin can partially restore cigarette smoke induced effects on Adipose derived Stem Cells

INTRODUCTION

Adipose derived Stem Cells (ASCs) have been proven to play a key role in tissue regeneration. However, exposure to large amounts of cigarette smoke can drastically diminish their function. Erythropoetin (EPO), can modulate cellular response to injury. Therefore, we investigated the ability of EPO to restore the regenerative function and differentiation capacity of ASCs.

MATERIAL AND METHODS

Human ASCs were isolated from abdominoplasty samples using standard isolation procedures. Cell identity was established by means of Fluorescence Activated Cell Scanning. Subsequently, isolated ASCs were cultivated with cigarette smoke extract both with and without EPO. Parameters investigated included cellular metabolic activity, adipogenic and osteogenic differentiation capacity, and in vitro wound closure capacity. For further enhancing wound closure, EPO was combined with Granulocyte Macrophage Colony Stimulating Factor (GM-CSF) or Stromal Derived Factor-1 alpha (SDF-1 a).

RESULTS

Cigarette smoke reduces adipogenic differentiation, the osteogenic differentiation capacity as well as the in vitro wound healing ability of human derived ASCs. EPO did not change metabolic activity of ASCs significantly. The addition of EPO could partially restore their function. The combination of EPO with GM-CSF or SDF-1 did not result in a synergistic effect regarding wound healing ability.

CONCLUSION

Exposure to cigarette smoke significantly reduced the regenerative potential of ASCs. Treatment of ASCs exposed to cigarette smoke with EPO has the potential to partially restore their function.