Project description:Cigarette smoke is a risk factor for inflammatory diseases, such as atherosclerosis. Tobacco smoke interacts with inflammatory cytokines to produce endothelial dysfunction and induces pro-inflammatory and pro-atherosclerotic effects in vascular tissue. Smooth muscle cells (SMCs) are present in the media of human arteries, and are considered protective against atherosclerotic plaque destabilization. Contractile SMCs are the most prominent cell type in the healthy vessel wall. SMCs are not terminally differentiated, and retain the ability to undergo a phenotypic switch from a contractile to a dedifferentiated synthetic state to express inflammatory markers and a phagocytic activity in response to environmental cues. The aim of our study was to evaluate the effects in human SMCs of lipophilic component from cigarette smoke condensate (CSC) and of hydrophilic components of Electronic-cigarette, Tobacco heating products, or cigarette smoke.
Project description:Purpose: Globally, many jurisdictions are legalizing or decriminalizing cannabis, creating a potential public health issue that would benefit from experimental evidence to inform policy, government regulations, and user practices. Tobacco smoke exposure science has created a body of knowledge that demonstrates the conclusive negative impacts on respiratory health; similar knowledge remains to be established for cannabis. To address this unmet need, we performed in vitro functional and transcriptomic experiments with a human airway epithelial cell line (Calu-3) exposed to cannabis smoke, with tobacco smoke as a positive control. Results: We demonstrate that cannabis smoke induced functional and transcriptional responses that overlapped with tobacco smoke. Ontology and pathway analysis revealed that cannabis smoke induced DNA replication and oxidative stress responses. Functionally, cannabis smoke impaired epithelial cell barrier function, antiviral responses, and increased inflammatory mediator production. Our study reveals striking similarities between cannabis and tobacco smoke exposure on impairing barrier function, suppressing antiviral pathways, potentiating of pro-inflammatory mediators, and inducing oncogenic and oxidative stress gene expression signatures. LABA/GC intervention in airway epithelial cells exposed to cannabis smoke reduces levels of pro-inflammatory (CXCL8) and antiviral (CXCL10) mediators, while transcriptomic signatures of neutrophil mediated immunity and oxidative stress remain elevated. Conclusions: Collectively our data suggest that cannabis smoke exposure is not innocuous and may possess many of the deleterious properties of tobacco smoke, warranting additional studies to support public policy, government regulations, and user practices.
Project description:This study reports a comparative assessment of the biological impact of a heated tobacco aerosol from the tobacco heating system (THS) 2.2 and smoke from a combustible 3R4F cigarette. Human organotypic bronchial epithelial cultures were exposed to an aerosol from THS2.2 (a candidate modified-risk tobacco product) or 3R4F smoke at similar nicotine concentrations. A systems toxicology approach was applied to enable a comprehensive exposure impact assessment. Culture histology, cytotoxicity, secreted pro-inflammatory mediators, ciliary beating, and genome-wide mRNA/miRNA profiles were assessed at various time points post-exposure. Series of experimental repetitions were conducted to increase the robustness of the assessment. At similar nicotine concentrations, THS2.2 aerosol elicited lower cytotoxicity compared with 3R4F smoke. No morphological change was observed following exposure to THS2.2 aerosol, even at nicotine concentration three times that of 3R4F smoke. Lower levels of secreted mediators and fewer miRNA alterations were observed following exposure to THS2.2 aerosol than following 3R4F smoke. Based on the computational analysis of the gene expression changes, 3R4F (0.13 mg nicotine/L) elicited the highest biological impact (100%) in the context of Cell Fate, Cell Proliferation, Cell Stress, and Inflammatory Network Models at 4 h post-exposure. Whereas, the corresponding impact of THS2.2 (0.14 mg nicotine/L) was 7.6%.
Project description:Our previous studies have shown that tobacco smoke exposure exacerbated the lung response to crystalline silica exposure in rats. The objective of the present study, a follow-up to our previous study, was to determine the effect of tobacco smoke exposure cessation on the lung response to crystalline silica exposure in the rats. Rats were exposed to air, crystalline silica (1 week followed by a 1 year progression/recovery period with no exposure), tobacco smoke (6 months of exposure followed by 6 months of recovery with no exposure), or crystalline silica (1 week) plus tobacco smoke (6 months of exposure followed by 6 months of recovery with no exposure). Lung toxicity was determined at the end of the 1-year progression/recovery period in all 4 groups of the rats. Silica exposure resulted in significant lung toxicity which was further exacerbated by tobacco smoke exposure in the rats. Cessation of cigarette smoke exposure did not result in reversal of the silica-induced lung toxicity despite exacerbation of the toxicity by tobacco smoke.
Project description:Along the trachea-bronchial tree, including the small airway region, cigarette smoke exposure induces inflammation, which can exacerbate the development of chronic obstructive pulmonary disease (COPD). The small airway region is known as the primary location of airway blockage in COPD and asthma. Therefore, evaluating exposure impact on the small airway is relevant for risk assessment. Using an in vitro human small airway culture model and a Systems Toxicology approach, this present study reports an assessment of the biological impact of an aerosol from a candidate modified-risk tobacco product, tobacco heating system (THS) 2.2, as compared with 3R4F smoke, at similar nicotine concentratng other functional measures (e.g., cytotoxicity, ciliary beating function, secretion of pro-inflammatory mediators) and histological assessment. The NPA methodology provides not only a qualitative measure of the exposure impact, but also a quantification of the exposure effect: the highest biological impact was observed in cultures 4 h post-exposure to 3R4F smoke at 0.15 mg nicotine/L (100% impact). In contrast, THS2.2 aerosol at similar nicotine concentration, only elicited 15% relative biological impact at 4 h post-exposure in the context of various biological processes modeled in the networks: Cell Fate, Cell Proliferation, Cell Stress, and Inflammatory Process Networks. Consistently, ciliary beating function and culture morphology were not remarkably altered in samples exposed to THS2.2 aerosol, even at nicotine concentration three times that of 3R4F smoke.
Project description:Along the trachea-bronchial tree, including the small airway region, cigarette smoke exposure induces inflammation, which can exacerbate the development of chronic obstructive pulmonary disease (COPD). The small airway region is known as the primary location of airway blockage in COPD and asthma. Therefore, evaluating exposure impact on the small airway is relevant for risk assessment. Using an in vitro human small airway culture model and a Systems Toxicology approach, this present study reports an assessment of the biological impact of an aerosol from a candidate modified-risk tobacco product, tobacco heating system (THS) 2.2, as compared with 3R4F smoke, at similar nicotine concentrating other functional measures (e.g., cytotoxicity, ciliary beating function, secretion of pro-inflammatory mediators) and histological assessment. The NPA methodology provides not only a qualitative measure of the exposure impact, but also a quantification of the exposure effect: the highest biological impact was observed in cultures 4 h post-exposure to 3R4F smoke at 0.15 mg nicotine/L (100% impact). In contrast, THS2.2 aerosol at similar nicotine concentration, only elicited 15% relative biological impact at 4 h post-exposure in the context of various biological processes modeled in the networks: Cell Fate, Cell Proliferation, Cell Stress, and Inflammatory Process Networks. Consistently, ciliary beating function and culture morphology were not remarkably altered in samples exposed to THS2.2 aerosol, even at nicotine concentration three times that of 3R4F smoke.
Project description:Previous studies have shown that smoking induces oxidative stress and inflammation, known factors that coincide with the development and progression of lung toxicity in response to crystalline silica exposure. Nevertheless, the precise role of tobacco smoke exposure on the lung response to tobacco smoke exposure and the underlying mechanisms remain largely elusive. Therefore, the objective of the present study was to determine the effect of smoking, if any, on silica-induced pulmonary toxicity and the underlying molecular mechanisms. Pulmonary toxicity and lung gene expression profiles were determined in rats exposed to air, crystalline silica, tobacco smoke, or crystalline silica plus tobacco smoke. Silica exposure resulted in significant pulmonary toxicity which was further exacerbated by tobacco smoke exposure in the rats. Significant differences in the gene expression profiles were detected in the lungs of the rats exposed to tobacco smoke, silica or a combination of both compared with the air exposed control rats.
Project description:Maternal smoking has a severe negative effect on all stages of pregnancy that in consequence impairs fetal growth and development. Tobacco smoke-related defects are well established at the clinical level; however, little is known about molecular mechanisms underlying these pathological conditions. We thus employed a genomic approach to determine transcriptome alterations induced by maternal smoking in pregnancy. We assayed gene expression profiles in peripheral blood (M) leukocytes and placentas (PL) of pregnant smokers and those without significant exposure, and in cord blood (D) leukocytes of their babies. Comparative analyses defined significant deregulation of 193 genes in M cells, 329 genes in placentas, and 49 genes in D cells of smokers. These genes were mainly involved in xenobiotic metabolism, oxidative stress, inflammation, immunity, hematopoiesis, trophoblast differentiation, and vascularization. Functional annotation of the deregulated genes outlined processes and pathways affected by tobacco smoke. In smoker newborns, we identified several deregulated pathways associated with autoimmune diseases. The study demonstrates a limited ability of placenta to modulate toxic effects of maternal tobacco use at the gene expression level.
Project description:Passive smoke intake by pregnant women may have detrimental effects such as spontaneous abortion, lower birth weight, stillbirth, and reduced infant lung function. To extend our knowledge on molecular effects of tobacco smoke exposure in pregnancy, we analyzed transcriptome alterations in passive smokers (PS) and compared them to those in active smokers (AS). Using Illumina Expression Beadchip with 24,526 transcript probes, gene expression patterns were assayed in placentas from PS (N=25) exposed to environmental tobacco smoke (ETS) throughout pregnancy and non-exposed (NS) counterparts (N=35), and in cord blood cells from their newborns. The ETS exposure was evaluated by questionnaire disclosure and cotinine measurement in maternal and cord bloods. A total of 196 genes were significantly deregulated in placentas of PS compared to NS. These genes were primary associated with extracellular matrix, apoptosis, blood clotting, response to stress, embryonic morphogenesis, and lipid metabolism. Cord blood of newborns of PS displayed differential expression of 116 genes encoding mainly neuronal factors, regulators of immunologic response, and protooncogenes. Gene ontology analyses highlighted some important biological processes that might be associated with placental insufficiency and fetal growth restriction in PS, such as fatty acid catabolism, coagulation, regulation of growth, and response to steroid hormone stimulus. The study demonstrates that even low dose exposure to ETS during pregnancy leads to the significant deregulation of transcriptional regulation in placental and fetal cells. The data suggest the effect of ETS on the fetus is primary indirect, mediated via deregulation of placental functions. Comparison of PS and AS indicated that ETS exposure and active smoking in pregnancy partly employ the same molecular mechanisms. A total of 60 women who gave birth to a baby in the Faculty Hospital Motol (Czech Republic) were enrolled into the study approved by the local Institutional Review Board. The participants signed written informed consent and self-reported information on tobacco smoke exposure (type of exposure, number of cigarettes per day, exposure period) and life style during pregnancy (alcohol drinking, diet, area of residency etc.). Further, the women completed the questionnaire on pregnancy/delivery course (complications, diseases, medication, and delivery mode) and newborn characteristics (physical parameters, Apgar score) with the assistance of gynecologist. Only women without any health complications during pregnancy and their newborns without manifestation of pathological abnormalities were included in the study. Based on self-reported tobacco smoke exposure, the women were divided into two groups, non-smokers (NS, N=35) and passive smokers (PS, N=25). Former and active smokers were excluded from the study. Exposure to tobacco smoke was further evaluated by measurement of plasma cotinine levels in maternal peripheral blood and newborn cord blood using radioimmunoassay.