In vitro effects of waterpipe smoke condensate on endothelial cell function: a potential risk factor for vascular disease

Central and Peripheral Hemodynamics in Young Adults Who Use Water Pipes and the Acute Effects of Water-Pipe Use

BACKGROUND

Tobacco use via water pipe (commonly referred to as water-pipe smoking [WPS]) is popular among young adults globally and exposes those who smoke to toxicants.

RESEARCH QUESTION

Is WPS associated with impaired measures of arterial function and does WPS acutely impair these measures in young adults?

STUDY DESIGN AND METHODS

We assessed heart rate (HR), brachial and aortic BP, HR-adjusted augmentation index (AI), and carotid-femoral pulse wave velocity (CFPWV) in 62 individuals who use water pipes and 34 individuals who have never used a water pipe recruited from the community (mean age, 22.5 ± 3.0 years; 48% female). Measurements were obtained before and after an outdoor session of WPS among participants who use water pipes and among the control group of participants who have never used a water pipe. Measurements were compared after vs before exposure and between those who use and those who do not use water pipes, adjusting for possible confounders using linear regression.

RESULTS

Participants who use water pipes and control participants had similar demographic characteristics. BP and HR increased acutely after WPS (brachial systolic BP by 4.13 mm Hg [95% CI, 1.91-6.36 mm Hg]; aortic systolic BP by 2.31 mm Hg [95% CI, 0.28-4.33 mm Hg]; brachial diastolic BP by 3.69 mm Hg [95% CI, 1.62-5.77 mm Hg]; aortic diastolic BP by 3.03 mm Hg [95% CI, 0.74-5.33 mm Hg]; and HR by 7.75 beats/min [95% CI, 5.46-10.04 beats/min]), but not in the control group. AI was significantly higher in participants who use water pipes compared with those who do not (9.02% vs 3.06%; P = .03), including after adjusting for BMI and family history of cardiovascular disease (β = 6.12; 95% CI, 0.55-11.69; P = .03) and when assessing habitual tobacco use via water-pipe extent (water pipes used/day × water-pipe use duration) in water-pipe-years (β = 2.51/water-pipe-year; 95% CI, 0.10-4.92/water-pipe-year; P = .04). However, CFPWV was similar in those who use water pipes and those who do not, and AI and CFPWV did not change acutely after WPS.

INTERPRETATION

In apparently healthy young individuals from the community, habitual WPS was associated with increased AI, a predictor of cardiovascular risk, and one WPS session acutely increased HR and brachial and aortic BP.

Exercise Training Attenuates Cardiac Vulnerability and Promotes Cardiac Resistance to Isoproterenol-Induced Injury Following Hookah Smoke Inhalation in Male Rats: Role of Klotho and Sirtuins

Hookah smoking is on the rise around the world. Present study investigated the heart resistance to harmful stress following long-term waterpipe tobacco smoking (WTS) and moderate-intensity exercise training intervention in male Wistar rats. Animals were randomly divided into a non-ischemic heart control group and four ischemic heart groups including ISO (isoproterenol-treated), Ex + ISO (subjected to exercise plus ISO), S + ISO (exposed to hookah smoke plus ISO), and Ex + S + ISO (subjected to exercise along with hookah smoke plus ISO). After eight weeks of training and WTS, heart ischemia induced by isoproterenol injections. Then, cardiac functional indices and some biochemical and histopathological parameters were assessed. WTS + ISO reduced systolic pressure, ± dP/dt max, and contractility indices (P < 0.001 vs. ISO group) and increased end diastolic pressure and Tau index (P < 0.001 vs. ISO) of the left ventricle. Also, WTS + ISO was associated with an increase in Bax protein level and Bax/Bcl-2 ratio (P < 0.05 and P < 001, respectively, vs. ISO group) as apoptotic markers of heart tissue. Hookah smoke significantly decreased SIRT1 (P < 0.05 and P < 0.001, respectively, vs. ISO) and klotho (P < 0.01 and P < 0.001, respectively, vs. ISO) in serum and heart, and SIRT3 and pS9-GSK-3β (P < 001 and P < 0.05, respectively, vs. ISO) in heart tissue. Combination of exercise with WTS prevented the hookah smoke-induced alterations in apoptotic markers, cardiac functional indices, and SIRT1, SIRT3, klotho, and pS9-GSK-3β proteins. The findings demonstrated that hookah smoke inhalation intensifies ventricular dysfunction and decreases heart resistance to harmful stresses. Moderate-intensity exercise training attenuated these complications partly through recovering the klotho and sirtuins levels and apoptosis-survival balancing.

Effect of Water-Pipe Smoking on the Normal Development of Zebrafish

Background: Among all types of tobacco consumption, Water-Pipe Smoking (WPS) is the most widely used in the Middle East and second-most in several other countries. The effect of WPS on normal development is not yet fully understood, thus the aim of this study is to explore the acute toxicity effects of WPS extract on zebrafish larvae. Methods: In this study, we compared the effects of WPS smoke condensates at concentrations varying from 50 to 200 µg/mL on developmental, cardiac, and behavioural (neurotoxicity) functions. Gene expression patterns of cardiac biomarkers were also evaluated by RT-qPCR. Results: Exposing zebrafish embryos to 50, 100, 150 and 200 µg/mL WPS for three days did not affect the normal morphology of Zebrafish embryos, as the tail flicking, behavioural and locomotion assays did not show any change. However, WPS deregulated cardiac markers including atrial natriuretic peptide (ANP/NPPA) and brain natriuretic peptide (BNP/NPPB). Furthermore, it induced apoptosis in a dose-dependent manner. Conclusion: Our data demonstrate that WPS can significantly affect specific cardiac parameters during the normal development of zebrafish. Further investigations are necessary to elucidate the pathogenic outcome of WPS on different aspects of human life, including pregnancy.

The association of waterpipe smoking with arterial stiffness and wave reflection in a community-based sample

PURPOSE

The evidence linking waterpipe smoking to cardiovascular disease is limited. We evaluated the association of waterpipe smoking (WPS) with arterial stiffness and wave reflection measured by augmentation pressure (AP), augmentation index (AIx), and carotid-femoral pulse wave velocity (CFPWV), which are validated predictors of cardiovascular disease.

MATERIALS AND METHODS

Community-based, cross-sectional study including 205 exclusive waterpipe smokers and 199 matched never-smokers aged 35 years or older (mean age 51.7 ± 8.9 years, 36% females). Smoking and its extent were assessed using a validated questionnaire and urine cotinine levels. CFPWV, AP, AIx (AP/aortic pulse pressure) and heart rate adjusted AIx (AIx@75) were determined using tonometry and compared between smokers and non-smokers, and the association of WPS with tonometry measures was assessed using linear regression adjusting for possible confounders.

RESULTS

Waterpipe smokers and non-smokers had similar mean age and sex distribution. Compared to non-smokers, waterpipe smokers had significantly higher adjusted AP (10.5 ± 3.9 vs. 9.4 ± 3.9 mmHg respectively; p = 0.01), AIx (28.1 ± 8.4 vs. 25.7 ± 8.5% respectively; p = 0.01) and AIx@75 (24.2 ± 8.7 vs. 21.8 ± 8.9% respectively; p = 0.01). AIx was significantly associated with WPS extent, measured by a number of waterpipe smoked/day (β = 1.04/waterpipe, 95%CI:[0.50-1.58]), duration of waterpipe smoking (β = 0.77/10-years, 95%CI:[0.16-1.38]), their products in waterpipe-years (β = 0.30/10-waterpipe-year, 95%CI:[0.12-0.47]) and plasma cotinine (β = 0.56/100 ng/ml, 95%CI:[0.14-0.98]), adjusting for possible confounders, and so were AP and AIx@75. CFPWV however, was not associated with waterpipe smoking.

CONCLUSION

In a community-based sample, exclusive WPS and its extent were associated with a dose-dependent increase in AIx and AP, accounting for other risk factors, suggesting that waterpipe smokers are at increased risk of cardiovascular disease.

Waterpipe smoke condensate influences epithelial to mesenchymal transition and interferes with the cytotoxic immune response in non-small cell lung cancer cell lines

Waterpipe tobacco smoking (WPS) continues to spread globally and presents serious health hazards. The aim of the present study was to investigate the effects of treatment with WPS condensate (WPSC) on lung cell proliferation and plasticity as well as tumor cell recognition and killing by natural killer (NK) cells using cytotoxicity assays. The results indicated that exposure of normal and cancer lung cell lines to WPSC resulted in a decrease in their in vitro growth in a dose-dependent manner and it induced tumor senescence. In addition, WPSC selectively caused DNA damage as revealed by an increase in γH2AX and 53BP1 in tumor lung cells. To gain further insight into the molecular mechanisms altered by WPSC, we conducted a global comprehensive transcriptome analysis of WPSC-treated tumor cells. Data analysis identified an expression profile of genes that best distinguished treated and non-treated cells involving several pathways. Of these pathways, we focused on those involved in epithelial to mesenchymal transition (EMT) and stemness. Results showed that WPSC induced an increase in SNAI2 expression associated with EMT, ACTA2 and SERPINE2 were involved in invasion and CD44 was associated with stemness. Furthermore, WPSC exposure increased the expression of inflammatory response genes including CASP1, IL1B, IL6 and CCL2. While immune synapse formation between NK and WPSC-treated lung cancer target cells was not affected, the capacity of NK cells to kill these target cells was reduced. The data reported in the present study are, to the best of our knowledge, the first in vitro demonstration of WPSC effects on lung cellular parameters providing evidence of its potential involvement in tumor physiology and development.

Longitudinal pathways of exclusive and polytobacco hookah use among youth, young adults and adults in the USA: findings from the PATH Study Waves 1-3 (2013-2016)

OBJECTIVE

The goal of this study is to examine cross-sectional rates of use and longitudinal pathways of hookah use among US youth (ages 12-17), young adults (ages 18-24), and adults 25+ (ages 25 and older).

DESIGN

Data were drawn from the first three waves (2013-2016) of the Population Assessment of Tobacco and Health Study, a nationally representative, longitudinal cohort study of US adults and youth. Respondents with data at all three waves (youth, n=11 046; young adults, n=6478; adults 25+, n=17 188) were included in longitudinal analyses.

RESULTS

Young adults had higher ever, past 12-month (P12M) and past 30-day cross-sectional prevalence of hookah use at each wave than youth or adults 25+. The majority of Wave 1 (W1) hookah users were P12M users of other tobacco products (youth: 73.9%, young adults: 80.5%, adults 25+: 83.2%). Most youth and adult W1 P12M hookah users discontinued use in Wave 2 or Wave 3 (youth: 58.0%, young adults: 47.5%, adults 25+: 63.4%). Most W1 P12M hookah polytobacco users used cigarettes (youth: 49.4%, young adults: 59.4%, adults 25+: 63.2%) and had lower rates of quitting all tobacco than exclusive hookah users or hookah polytobacco users who did not use cigarettes.

CONCLUSIONS

Hookah use is more common among young adults than among youth or adults 25+. Discontinuing hookah use is the most common pathway among exclusive or polytobacco hookah users. Understanding longitudinal transitions in hookah use is important in understanding behavioural outcomes at the population level.

Immune modulation by chronic exposure to waterpipe smoke and immediate-early gene regulation in murine lungs

OBJECTIVE

We investigated the effects of chronic waterpipe (WP) smoke on pulmonary function and immune response in a murine model using a research-grade WP and the effects of acute exposure on the regulation of immediate-early genes (IEGs).

METHODS

WP smoke was generated using three WP smoke puffing regimens based on the Beirut regimen. WP smoke samples generated under these puffing regimens were quantified for nicotine concentration. Mice were chronically exposed for 6 months followed by assessment of pulmonary function and airway inflammation. Transcriptomic analysis using RNAseq was conducted after acute exposure to characterise the IEG response. These biomarkers were then compared with those generated after exposure to dry smoke (without water added to the WP bowl).

RESULTS

We determined that nicotine composition in WP smoke ranged from 0.4 to 2.5 mg per puffing session. The lung immune response was sensitive to the incremental severity of chronic exposure, with modest decreases in airway inflammatory cells and chemokine levels compared with air-exposed controls. Pulmonary function was unmodified by chronic WP exposure. Acute WP exposure was found to activate the immune response and identified known and novel IEG as potential biomarkers of WP exposure.

CONCLUSION

Chronic exposure to WP smoke leads to immune suppression without significant changes to pulmonary function. Transcriptomic analysis of the lung after acute exposure to WP smoke showed activation of the immune response and revealed IEGs that are common to WP and dry smoke, as well as pools of IEGs unique to each exposure, identifying potential biomarkers specific to WP exposure.

The effects of hookah/waterpipe smoking on general health and the cardiovascular system

Hookah or waterpipe smoking or use is an emerging trend in the US population, especially among the youth. The misperception of hookah being less harmful than cigarettes and the availability of different but "appealing" flavors are considered among the main reasons for this trend. Hookah users however are exposed to many of the same toxic compounds/by-products as cigarette users, but at dramatically higher levels, which might lead to more severe negative health effects. In fact, hookah users are at risks of infections, cancers, lung disease, and other medical conditions. Moreover, because of the overlapping toxicant/chemical profile to conventional cigarettes, hookah smoke effects on the cardiovascular system are thought to be comparable to those of conventional cigarettes. A major source of tobacco addiction is nicotine, whose levels in hookah are extremely variable as they depend on the type of tobacco used. Taken together, in this review of literature, we will provide insights on the negative health effects of hookah in general, with a focus on what is known regarding its impact on the cardiovascular system.

Substantial Toxic Effect of Water-Pipe Smoking on the Early Stage of Embryonic Development

Background

Water-pipe smoking (WPS) is the most widespread tobacco use in the Middle-East, and is rapidly spreading globally. Smoke from WP contains most of the compounds present in cigarette smoke, although in different proportions. WPS is associated with the risk of several human diseases; however, its impact on the early stage of normal development has not been investigated yet. Thus, in this investigation, we assess the effect of WPS on the embryo at the early stage of development.

Methods

Chicken embryos at 3 days of incubations were used in this study. Meanwhile, we explored the outcome of WPS on angiogenesis using the chorioallantoic membrane (CAM) of the chicken embryos. Finally, quantitative real-time polymerase chain reaction was used to study the regulation of some key control genes of cell proliferation, apoptosis, and migration.

Results

Our data reveal that WPS inhibits angiogenesis of the CAM and in embryos in comparison with their matched controls; in addition, WPS-exposed embryos show slight reduction in their sizes. We also noted that around 80% of WPS-exposed embryos die before 10 days of incubation. More significantly, WPS induces upregulations of BCL-2, Caspase-8, ATF-3, INHIB-A, and Cadherin 6 genes, which are important key regulators of cell apoptosis, proliferation, and migration.

Conclusion

Our data reveal, for the first time, that WPS has very toxic effects during the early stage of embryogenesis. Thus, we believe that further studies are required to elucidate the pathogenic effect of WPS on human health especially on the embryo at the early stage of its development.

Implications

This investigation addresses an important gap on the outcome of WPS during the early stage of embryogenesis. Data of this study point out that WPS can have a very toxic effect on the embryo at this stage. Additionally, results from this report display for the first time that WPS can damage normal angiogenesis of the embryo thus provoking a significant number of embryonic death. Moreover, this study reveals that this effect can occur via the deregulation of several genes related to cell apoptosis, proliferation, and migration.

Effect of Prenatal Waterpipe Tobacco Smoke Exposure on Cardiac Biomarkers in Adult Offspring Rats

Introduction:

The prevalence of waterpipe tobacco smoke (WTS) consumption is increased among pregnant woman. Prenatal cigarette smoke exposure increased the risk of developing cardiovascular diseases in offspring. The current study examined the effect of prenatal WTS exposure on inflammatory profile, oxidative stress, and cardiac biomarkers in adult offspring rats.

Methods:

Female rats received WTS (2 hours per day) or fresh air 1 day prior to mating and throughout the pregnancy period. The body and heart masses were measured in male offspring rats. The level of oxidative stress biomarkers, nitrate, inflammatory mediators (interleukin 6 [IL-6], tumor necrosis factor alpha [TNF-α]), and gene expression of protein kinase C epsilon, angiotensin 2 receptor one, and transforming growth factor beta1 were measured in cardiac tissue homogenates of 13-week-old male offspring rats.

Results:

Prenatal WTS exposure reduced body weight and increased heart to body weight ratio ( P < .05). Prenatal WTS exposure did not affect oxidative stress biomarkers (superoxide dismutase, glutathione peroxidase, and thiobarbituric acid reactive substances) but significantly increased catalase activity and nitrate level ( P < .05) in cardiac tissue of adult male offspring rats. In addition, prenatal exposure to WTS did not affect cardiac level of TNF-α and IL-6 as well as the gene expression of different cardiac modulators in adult male offspring rats ( P > .05).

Conclusion:

Prenatal WTS exposure has detrimental consequences on adult offspring rats by increasing the ratio of heart to body mass, increasing the catalase activity and nitrate level in cardiac tissue of adult male offspring rats.

The Association of Water-Pipe Smoking and Coronary Artery Calcium in a Community-Based Sample

BACKGROUND

Water-pipe smoking is increasing in popularity, driven partly by a perception of reduced harm compared with cigarette smoking. This study evaluates the association of water-pipe smoking with coronary artery calcium (CAC), a marker of coronary heart disease (CHD) risk, in a community-based sample.

METHODS

A total of 175 exclusive water-pipe smokers and 170 nonsmokers, ≥ 35 years of age, were recruited from the community in Lebanon and Qatar. Water-pipe smoking was assessed using a validated questionnaire. CAC score was assessed using multidetector CT scan. The association of water-pipe smoking with the presence and extent of CAC was evaluated using regression analyses adjusted for CHD risk factors.

RESULTS

CAC was present in 41% of water-pipe smokers vs 28% of nonsmokers (P = .01), with an average CAC score ± SD of 90.6 ± 400.3 Agatston units (AUs) in water-pipe smokers and 52.4 ± 218.6 AUs in nonsmokers. In adjusted analyses, water-pipe smokers had significantly higher adjusted odds of having CAC (OR = 2.20; 95% CI, 1.20-4.01; P = .01) and being in the high CHD risk category defined by CAC > 300 AUs (OR = 3.41; 95% CI, 1.08-10.77; P = .04) or CAC > 75% of age, sex, and race-predicted (OR = 3.11; 95% CI, 1.55-6.24; P = .001) than nonsmokers. CAC extent was significantly associated with water-pipe smoking extent measured by smoking duration (β = 0.17/year; 95% CI, 0.05-0.29; P = .004) or the product of smoking duration and the number of water pipes smoked daily (β = 0.04/water-pipe-year; 95% CI, 0.003-0.07; P = .03).

CONCLUSIONS

Exclusive water-pipe smoking was associated with the presence and extent of CAC, with twice the risk of having CAC and three times the risk of being in the high CHD risk category while accounting for other risk factors.

Comparison of a preferred versus non-preferred waterpipe tobacco flavour: subjective experience, smoking behaviour and toxicant exposure

INTRODUCTION

One possible reason for the rapid proliferation of waterpipe (WP) smoking is the pervasive use of flavoured WP tobacco. To begin to understand the impact of WP tobacco flavours, the current study examined the impact of a preferred WP tobacco flavour compared with a non-preferred tobacco flavoured control on user's smoking behaviour, toxicant exposure and subjective smoking experience.

METHOD

Thirty-six current WP smokers completed two, 45-minute ad libitum smoking sessions (preferred flavour vs non-preferred tobacco flavour control) in a randomised cross-over design. Participants completed survey questionnaires assessing subjective smoking experience, exhaled carbon monoxide (eCO) testing, and provided blood samples for monitoring plasma nicotine. WP smoking topography was measured continuously throughout the smoking session.

RESULTS

While participants reported an enhanced subjective smoking experience including greater interest in continued use, greater pleasure derived from smoking, increased liking and enjoyment, and willingness to continue use after smoking their preferred WP tobacco flavour (p values <0.05), no significant differences were observed in nicotine and carbon monoxide boost between flavour preparations. Greater average puff volume (p=0.018) was observed during the non-preferred flavour session. While not significant, measures of flow rate, interpuff interval (IPI), and total number of puffs were trending towards significance (p values <0.10), with decreased IPI and greater total number of puffs during the preferred flavour session.

DISCUSSION

The current study is the first to examine flavours in WP smoking by measuring preferred versus control preparations to understand the impact on subjective experience, smoking behaviour and toxicant exposure. The pattern of results suggests that even this relatively minor manipulation resulted in significant changes in subjective experience. These results indicate a possible need for regulations restricting flavours in WP tobacco as with combustible cigarettes.

Oxidative Stress: A Unifying Mechanism for Cell Damage Induced by Noise, (Water-Pipe) Smoking, and Emotional Stress-Therapeutic Strategies Targeting Redox Imbalance

SIGNIFICANCE

Modern technologies have eased our lives but these conveniences can impact our lifestyles in destructive ways. Noise pollution, mental stresses, and smoking (as a stress-relieving solution) are some environmental hazards that affect our well-being and healthcare budgets. Scrutinizing their pathophysiology could lead to solutions to reduce their harmful effects. Recent Advances: Oxidative stress plays an important role in initiating local and systemic inflammation after noise pollution, mental stress, and smoking. Lipid peroxidation and release of lysolipid by-products, disturbance in activation and function of nuclear factor erythroid 2-related factor 2 (Nrf2), induction of stress hormones and their secondary effects on intracellular kinases, and dysregulation of intracellular Ca²⁺ can all potentially trigger other vicious cycles. Recent clinical data suggest that boosting the antioxidant system through nonpharmacological measures, for example, lifestyle changes that include exercise have benefits that cannot easily be achieved with pharmacological interventions alone.

CRITICAL ISSUES

Indiscriminate manipulation of the cellular redox network could lead to a new series of ailments. An ideal approach requires meticulous scrutiny of redox balance mechanisms for individual pathologies so as to create new treatment strategies that target key pathways while minimizing side effects.

FUTURE DIRECTIONS

Extrapolating our understanding of redox balance to other debilitating conditions such as diabetes and the metabolic syndrome could potentially lead to devising a unifying therapeutic strategy. Antioxid. Redox Signal. 28, 741-759.

Electronic Cigarette Smoke Impairs Normal Mesenchymal Stem Cell Differentiation

Electronic cigarettes (e-cigarettes) are promoted as low-risk alternatives to combustible cigarettes. However, the effects of chronic inhalation of potential toxicants emitted by ecigarettes remain largely unexamined. It is conceivable that smoking-induced chronic diseases result in cellular injury, in the absence of effective repair by stem cells. This study evaluates the effect of cigarette and e-cigarette aerosol extracts on the survival and differentiation of bone marrow-derived mesenchymal stem cells (MSCs). MSC growth and osteogenic differentiation were examined after exposure to smoke extracts. Data revealed detrimental effects of both cigarette and e-cigarette extracts on MSC morphology and growth. Levels and activity of alkaline phosphatase, an osteogenic marker, decreased and induction of osteoblastic differentiation was impaired. Both smoke extracts prevented osteogenic differentiation from progressing, evident by decreased expression of terminal osteogenic markers and mineralization. Elevated levels of reactive oxygen species (ROS) were detected in cells exposed to smoke extracts. Moreover, decreased differentiation potential was concomitant with severe down-regulation of Connexin 43 expression, leading to the loss of gap junction-mediated communication, which together with elevated ROS levels, could explain decreased proliferation and loss of differentiation potential. Hence, e-cigarettes present similar risk as combustible cigarettes with respect to tissue repair impairment.

Hookah tobacco smoking in a large urban sample of adult cigarette smokers: Links with alcohol and poly-tobacco use

Hookah tobacco smoking (HTS) has been increasing, particularly among young adults and has similar health effects compared to cigarette smoking. The link between HTS and poly-tobacco use is well documented, but fewer show an association between HTS and alcohol use. It is essential to identify factors that increase the risk for or addictiveness and consequences of HTS, given its growing prevalence. This study examined whether the association between HTS and poly-tobacco use differed as a function of age and alcohol consumption within in a sample of 1223 adult cigarette smokers. Approximately 20% of participants reported HTS. Compared to non-users, hookah users were more likely to be male, highly educated, and to report drug and alcohol use, binge drinking, and poly-tobacco use but were less likely to be heavy smokers (≥10 cigarettes per day). Regression analyses predicting number of tobacco products used (excluding cigarettes and HTS) indicated a three-way interaction of HTS, frequency of alcohol use, and age such that the association between HTS and number of tobacco products used was strongest for younger respondents who consumed alcohol more frequently. As observed in previous studies, alcohol is an important risk factor in the relationship between HTS and poly-tobacco use, particularly among younger cigarette smokers. The links between alcohol, HTS, and poly-tobacco use should be considered when developing HTS education and prevention materials directed toward younger cigarette smokers. Findings provide information relevant to FDA's interest in the addiction potential of HTS and its link to poly-tobacco use.

Water-pipe smoke condensate increases the internalization of Mycobacterium Bovis of type II alveolar epithelial cells (A549)

BACKGROUND

Tuberculosis (TB) is a major global health problem, and there is an association between tobacco smoke and TB. Water pipe smoking has become an increasing problem not only in Middle Eastern countries but also globally because users consider it as safer than cigarettes. The presence of high levels of toxic substances in water-pipe smoke may be a predisposing factor that enhances the incidence of pulmonary disorders. For example, uncontrolled macropinocytosis in alveolar epithelial cells following exposure to water-pipe smoke may predispose subjects to pulmonary infection. Here, we studied the effects of water-pipe condense (WPC) on the internalization of Mycobacterium Bovis BCG by macropinocytosis in the alveolar epithelial cell line A549.

METHODS

A549 cells were exposed to WPC (4 mg/ml) for 24, 48, 72 and 96 h. Cell viability was studied using the methyl thiazolyldipenyl-tetrazolium bromide (MTT) reduction assay and proliferation by bromodeoxyUridine (BrdU) incorporation. Cells were exposed to FITC-Dextran (1 mg/ml) (as a control) and FITC-BCG (MOI = 10) for 20 min at 37 °C before cells were collected and the uptake of BCG-FITC determined by flow cytometry. Similar experiments were performed at 4 °C as a control. The Rho-associated protein kinase (ROCK) inhibitor Y-27632 (1 μM) was used to assess the mechanism by which WPC enhanced BCG uptake.

RESULTS

WPC (4 mg/ml) increased the uptake of BCG-FITC after 72 (1.3 ± 0.1 fold, p < 0.05) and 96 (1.4 ± 0.05 fold, p < 0.05) hours. No effect on BCG-FITC uptake was observed at 24 or 48 h. WPC also significantly increased the uptake of FITC-Dextran (2.9 ± 0.3 fold, p < 0.05) after 24 h. WPC significantly decreased cell viability after 24 (84 ± 2%, p < 0.05), 48 (78±, 3%, p < 0.05), 72 (64 ± 2%, p < 0.05) and 96 h (45 ± 2%, p < 0.05). Y-27632 completely attenuated the increased uptake of BCG by WPC. Cell proliferation showed a decreasing trend in a time-dependent manner with WPC exposure.

CONCLUSION

WPC exposure increased epithelial cell endocytosis activity and death as well as enhancing their capacity for macropinocytosis. Our in vitro data indicates possible harmful effects of WPC on the ability of lung epithelial cells to phagocytose mycobacterium.

Health Effects of Waterpipe Tobacco Use: Getting the Public Health Message Just Right

Many public health messages benchmark the harms of waterpipe tobacco against those of cigarettes, usually using numerical magnitudes of risk. This approach, although well intentioned, could be perceived as alarmist, damaging scientific credibility, and giving an unintended impression that one tobacco product is less harmful than the other. This commentary makes clear the harm waterpipe tobacco smoking poses to public health by describing its mechanism of use, consumption uptake, toxicologic profile, and documented health outcomes, as well as challenge existing thinking that toxicologic assessments are the most appropriate way to frame waterpipe tobacco health promotion messages. How can we describe the health effects of waterpipe tobacco without undermining its toxicity nor falling into the temptation of alarmist messaging? Several recommendations are provided.

Increasing popularity of waterpipe tobacco smoking and electronic cigarette use: Implications for oral healthcare

Cigarette smoking increases the risk of developing several systemic conditions including cancer, cardiovascular and pulmonary diseases. Cigarette smoking is also detrimental to oral health as it increases the incidence and severity of oral cancer, periodontal diseases and peri-implantitis, as well as impacting negatively on the dental patients' response to therapy. Therefore, consideration of smoking behavior and recommendation of smoking cessation are important parts of dental treatment planning. However, cigarettes are no longer the most popular form of tobacco use among adolescents in the United States and globally. In recent years, tobacco smoking using a waterpipe ("hookah," "shisha") and use of electronic cigarettes (ECIGs) has increased significantly. Thus, dental clinicians likely will treat more patients who are waterpipe and/or ECIG users. Yet, the literature on the health effects of waterpipe and ECIGs use is sparse. Both waterpipe and ECIGs deliver the dependence-producing drug nicotine. Waterpipe tobacco smoking has been associated with periodontitis, dry socket, premalignant lesions, and oral and esophageal cancer. The health effects of long-term ECIG use are unknown. The purpose of this review is to inform healthcare professionals about waterpipes and ECIGs, highlight emerging evidence on the biological effects of these increasingly popular tobacco products, and introduce perspectives for dental patient management and future research.

CD200Fc attenuates inflammatory responses and maintains barrier function by suppressing NF-κB pathway in cigarette smoke extract induced endothelial cells

BACKGROUND

Recent evidence suggests that CD200 fusion protein (CD200Fc), a CD200R1 agonist may attenuate inflammatory responses in autoimmune diseases and neuro-degeneration. While, little is known about the function of CD200Fc in cigarette smoke extract (CSE)-induced mouse Cardiac Microvascular Endothelial Cells (mCMECs). The present study was designed to elucidate the effects of CD200Fc on CSE-induced vascular endothelial barrier (VEB) dysfunction and inflammatory responses, which is a highly clinically relevant model of smoking related cardiovascular diseases.

METHODS

mCMECs were pre-treated with 1, 10 and 100μg/ml CD200Fc for 24h respectively, and then treated with 250μg/ml CSE for different times (24h or 120min). The transepithelial electrical resistance (TEER) and transport of fluorescent markers were used to measure VEB function in CSE-induced mCMECs. Western blot and immunofluorescent staining analysis were used to detect the expression of tight junction proteins, such as Zona Occludens-1 (ZO-1) and Claudin-1 in CSE-induced mCMECs. We measured the expression of pro-inflammatory cytokines in CSE-induced mCMECs by using ELISA and RT-PCR. In addition, the NF-κB activity in CSE-induced mCMECs were investigated by using nuclear/cytosol fractionation and western blot analysis.

RESULTS

In vitro treatment with CSE increased the transport of fluorescent markers and decreased TEER levels in mCMECs, respectively, which were attenuated by CD200Fc (10 and 100μg/ml) pretreatment. The CSE-induced up-regulation of pro-inflammatory cytokines such as Cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), platelet endothelial cell adhesion molecule-1 (PECAM-1), vascular cell adhesion molecule-1 (ICAM-1), Prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-8 in mCMECs was also abrogated by CD200Fc (10 and 100μg/ml) pretreatment. CD200Fc also inhibited CSE-induced nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation in mCMECs, such as inhibition of its DNA binding activity, phosphorylated expression, and translocation to nucleus.

CONCLUSION

Thus, CD200Fc exert anti-inflammatory effect and protect VEB function in CSE-induced mCMECs. The vasoprotective effects of CD200Fc may be specifically beneficial in pathophysiological conditions associated with smoking related cardiovascular diseases.

Waterpipe smoking and risk of coronary artery disease

PURPOSE OF REVIEW

Smoking tobacco using a water pipe is becoming more prevalent globally, particularly amongst younger populations. In addition to its growing popularity, more evidence is emerging regarding associated harm, and several misconceptions exist concerning the likely adverse health effects of waterpipe smoking (WPS). It is timely, therefore, to examine the body of evidence linking WPS to coronary artery disease (CAD). Here, we review the direct evidence linking WPS to CAD and examine additional, indirect evidence of associated harm. We discuss the clinical and public health implications of the current evidence and provide suggestions for further research.

RECENT FINDINGS

A multicentre case-control study in Lebanon has recently demonstrated an association between WPS and CAD. There are few prior studies making this direct link. However, a large body of evidence has emerged showing close similarities between WPS and cigarette smoking with regard to the toxicity of smoke and acute inflammatory and haemodynamic effects following exposure to it.

SUMMARY

There are consistent similarities between WPS and cigarette smoking in regard to association with CAD, the nature of the smoke produced, and the acute haemodynamic effects and inflammatory responses that follow exposure. These findings justify both public health and clinical interventions to reduce WPS. Further studies are warranted to confirm a causal association between WPS and CAD.

Nicotine exposure induces bronchial epithelial cell apoptosis and senescence via ROS mediated autophagy-impairment

Waterpipe smoking and e-cigarette vaping, the non-combustible sources of inhaled nicotine exposure are increasingly becoming popular and marketed as safer alternative to cigarette smoking. Hence, this study was designed to investigate the impact of inhaled nicotine exposure on disease causing COPD-emphysema mechanisms. For in vitro studies, human bronchial epithelial cells (Beas2b) were treated with waterpipe smoke extract (WPSE, 5%), nicotine (5mM), and/or cysteamine (250μM, an autophagy inducer and anti-oxidant drug), for 6hrs. We observed significantly (p<0.05) increased ubiquitinated protein-accumulation in the insoluble protein fractions of Beas2b cells treated with WPSE or nicotine that could be rescued by cysteamine treatment, suggesting aggresome-formation and autophagy-impairment. Moreover, our data also demonstrate that both WPSE and nicotine exposure significantly (p<0.05) elevates Ub-LC3β co-localization to aggresome-bodies while inducing Ub-p62 co-expression/accumulation, verifying autophagy-impairment. We also found that WPSE and nicotine exposure impacts Beas2b cell viability by significantly (p<0.05) inducing cellular apoptosis/senescence via ROS-activation, as it could be controlled by cysteamine, which is known to have an anti-oxidant property. For murine studies, C57BL/6 mice were administered with inhaled nicotine (intranasal, 500μg/mouse/day for 5 days), as an experimental model of non-combustible nicotine exposure. The inhaled nicotine exposure mediated oxidative-stress induces autophagy-impairment in the murine lungs as seen by significant (p<0.05, n=4) increase in the expression levels of nitrotyrosine protein-adduct (oxidative-stress marker, soluble-fraction) and Ub/p62/VCP (impaired-autophagy marker, insoluble-fraction). Overall, our data shows that nicotine, a common component of WPS, e-cigarette vapor and cigarette smoke, induces bronchial epithelial cell apoptosis and senescence via ROS mediated autophagy-impairment as a potential mechanism for COPD-emphysema pathogenesis.

A Systematic Review of Effects of Waterpipe Smoking on Cardiovascular and Respiratory Health Outcomes

BACKGROUND

Waterpipe smoking (WPS) is a social custom common in many Middle Eastern, North African, and Asian countries and has become increasingly popular in the US, especially among youth; however, WPS smoking may be increasing in the US adult population as well. There is a common belief among waterpipe (WP) smokers that WPS is less harmful than smoking cigarettes. Thus, this review aims to systematically explore the literature on the effects of WP tobacco smoking with a particular focus on cardiovascular and respiratory health outcomes as well as on oxidative stress, immunity, and cell cycle interference health outcomes.

METHODOLOGY

We conducted a systematic review, guided by the criteria of The Preferred Reporting Items for Systematic Reviews and Meta-Analyses, using the following online databases MEDLINE, CINAHL, ScienceDirect, PMC, and Cochrane Library. Results were summarized qualitatively.

RESULTS

Forty studies met the inclusion criteria established for this review. Based on the existing evidence, several cardiovascular and respiratory physiologic health indicators and conditions have been shown to be negatively affected by WPS. In addition to the effects of nicotine and chemical toxicant exposures, WPS was significantly associated with an increase in heart rate, blood pressure, and lower pulmonary function test results, as well as a number of health conditions such as lung cancer, alterations in oxidative stress, immunity, and cell cycle interference.

CONCLUSION

The current literature provides evidence that WPS is associated with a number of negative health indicators and outcomes. There is need for more research related to WPS and its effects on health so that appropriate campaigns and prevention interventions can be implemented to control the epidemic increase of WPS in the US.

Secondhand hookah smoke: an occupational hazard for hookah bar employees

BACKGROUND

Despite the increasing popularity of hookah bars, there is a lack of research assessing the health effects of hookah smoke among employees. This study investigated indoor air quality in hookah bars and the health effects of secondhand hookah smoke on hookah bar workers.

METHODS

Air samples were collected during the work shift of 10 workers in hookah bars in New York City (NYC). Air measurements of fine particulate matter (PM_2.5), fine black carbon (BC_2.5), carbon monoxide (CO), and nicotine were collected during each work shift. Blood pressure and heart rate, markers of active smoking and secondhand smoke exposure (exhaled CO and saliva cotinine levels), and selected inflammatory cytokines in blood (ineterleukin (IL)-1b, IL-6, IL-8, interferon γ (IFN-γ), tumour necrosis factor (TNF-α)) were assessed in workers immediately prior to and immediately after their work shift.

RESULTS

The PM_2.5 (gravimetric) and BC_2.5 concentrations in indoor air varied greatly among the work shifts with mean levels of 363.8 µg/m³ and 2.2 µg/m³, respectively. The mean CO level was 12.9 ppm with a peak value of 22.5 ppm CO observed in one hookah bar. While heart rate was elevated by 6 bpm after occupational exposure, this change was not statistically significant. Levels of inflammatory cytokines in blood were all increased at postshift compared to preshift testing with IFN-Υ increasing from 0.85 (0.13) to 1.6 (0.25) (mean (standard error of the mean; SEM)) pg/mL (p<0.01). Exhaled CO levels were significantly elevated after the work shift with 2 of 10 workers having values >90 ppm exhaled CO.

CONCLUSIONS

These results demonstrate that hookah bars have elevated concentrations of indoor air pollutants that appear to cause adverse health effects in employees. These data indicate the need for further research and a marked need for better air quality monitoring and policies in such establishments to improve the indoor air quality for workers and patrons.

A Study of the Use, Knowledge, and Beliefs About Cigarettes and Alternative Tobacco Products Among Students at One U.S. Medical School

PURPOSE

In the United States, the prevalence of the use of alternative tobacco products (ATPs) (e.g., hookahs, e-cigarettes, cigars/cigarillos) has increased sharply. As future health care providers, medical students will play a critical role in health promotion and disease prevention. This study investigated medical students' use, knowledge, and beliefs about cigarettes and ATPs.

METHOD

In 2014, the authors surveyed all students enrolled at one medical school in New York City. The survey included questions about personal use of tobacco products, perceptions about the harms of ATPs and their role in disease causation, education about ATPs, and cessation training and practices related to ATPs and cigarettes. The authors compared results across medical school classes.

RESULTS

Of 720 students, 431 (59.9%) completed the survey. Of those, 64 (14.7%) were current users of tobacco or smoking products, including cigarettes (17; 3.9%), ATPs (21; 4.8%), or marijuana (39; 8.9%). Many believed that ATPs contributed less than cigarettes to various diseases. Respondents received less cessation training regarding ATPs than cigarettes (P < .0001). They felt less confident providing ATP cessation counseling than cigarette cessation counseling (P < .0001) and were less likely to report counseling patients on ATP cessation than cigarette cessation (46 [10.7%] versus 280 [64.8%], P < .0001).

CONCLUSIONS

A concerning percentage of surveyed medical students use tobacco products, including ATPs, and lack the knowledge, education, and cessation counseling skills to provide accurate information about them to patients. ATP education should be added to medical school curricula to address this gap.

Correlates of hookah use and predictors of hookah trial in U.S. young adults

INTRODUCTION

Hookah, or waterpipe, tobacco smoking has increased among young adults (YAs) in the U.S., but few prospective studies have examined predictors of hookah use. The current study examined correlates of hookah use and predictors of hookah initiation at a 6-month follow-up in a nationally representative, prospective sample of U.S. YAs.

METHODS

Data were drawn from a subset of participants aged 18-24 years at study entry from two waves of the Legacy Young Adult Cohort Study. Wave 5 was completed in July 2013 by 1,555 participants and 74% (n=1,150) completed follow-up 6 months later in January 2014. Weighted bivariate and multivariable analyses were conducted in June 2014 to estimate the prevalence and correlates of ever and past 30-day hookah use and to examine associations between baseline covariates and hookah initiation 6 months later.

RESULTS

At baseline (Wave 5), almost 25% of the sample had ever used hookah and 4% reported past 30-day use. Alcohol, marijuana, and cigarette use were more prevalent among ever and past 30-day hookah users than among never users. Eight percent of never users at baseline reported trying hookah at the 6-month follow-up. Significant predictors of hookah trial in a multivariable model included college enrollment; alcohol, marijuana, and cigarette use; and perceptions that hookah is less harmful than cigarettes.

CONCLUSIONS

Results highlight rapid transitions in hookah use and several risk factors for initiation. Future studies should examine how these factors could be used as intervention targets to reduce tobacco use in this vulnerable age group.

Toxicant content, physical properties and biological activity of waterpipe tobacco smoke and its tobacco-free alternatives

OBJECTIVES

Waterpipe smoking using sweetened, flavoured tobacco products has become a widespread global phenomenon. In this paper, we review chemical, physical and biological properties of waterpipe smoke.

DATA SOURCES

Peer-reviewed publications indexed in major databases between 1991 and 2014. Search keywords included a combination of: waterpipe, narghile, hookah, shisha along with names of chemical compounds and classes of compounds, in addition to terms commonly used in cellular biology and aerosol sizing.

STUDY SELECTION

The search was limited to articles published in English which reported novel data on waterpipe tobacco smoke (WTS) toxicant content, biological activity or particle size and which met various criteria for analytical rigour including: method specificity and selectivity, precision, accuracy and recovery, linearity, range, and stability.

DATA EXTRACTION

Multiple researchers reviewed the reports and collectively agreed on which data were pertinent for inclusion.

DATA SYNTHESIS

Waterpipe smoke contains significant concentrations of toxicants thought to cause dependence, heart disease, lung disease and cancer in cigarette smokers, and includes 27 known or suspected carcinogens. Waterpipe smoke is a respirable aerosol that induces cellular responses associated with pulmonary and arterial diseases. Except nicotine, smoke generated using tobacco-free preparations marketed for 'health conscious' users contains the same or greater doses of toxicants, with the same cellular effects as conventional products. Toxicant yield data from the analytical laboratory are consistent with studies of exposure biomarkers in waterpipe users.

CONCLUSIONS

A sufficient evidence base exists to support public health interventions that highlight the fact that WTS presents a serious inhalation hazard.

Comparison of puff topography, toxicant exposure, and subjective effects in low- and high-frequency waterpipe users: a double-blind, placebo-control study

INTRODUCTION

Clinical laboratory work among intermittent and daily waterpipe tobacco smokers has revealed significant risks for tobacco dependence and disease associated with waterpipe tobacco smoking (WTS). No studies have compared these groups directly. This study examined whether WTS frequency was associated with differential puff topography, toxicant exposure, and subjective response using a placebo-control design.

METHODS

Eighty participants reporting WTS of 2-5 episodes (LOW; n = 63) or ≥20 episodes (HIGH; n = 17) per month for ≥6 months completed 2 double-blind, counterbalanced 2-hr sessions that were preceded by ≥12hr of tobacco abstinence. Sessions differed by product smoked ad libitum for 45+ min: preferred brand/flavor of waterpipe tobacco (active) or a flavor-matched tobacco-free waterpipe product (placebo). Outcomes included puff topography, plasma nicotine, carboxyhemoglobin (COHb), and subjective response.

RESULTS

HIGH users had more puffs, shorter inter-puff-intervals, and a higher total puff volume for placebo relative to active, as well as relative to LOW users during placebo. Plasma nicotine concentrations increased when smoking active (but not placebo) with no significant differences between groups at 25min post-product administration. COHb increased significantly during all conditions; the largest increase was for HIGH users when smoking placebo. There was some evidence of higher baseline scores for nicotine/tobacco nicotine abstinence symptomology.

CONCLUSIONS

Higher frequency waterpipe users may be more sensitive to the effects of waterpipe smoke nicotine content. Among HIGH users, higher baseline nicotine/tobacco abstinence symptoms may indicate greater nicotine dependence. These data support continued surveillance of WTS and development of dependence measures specific to this product.

The growing epidemic of water pipe smoking: health effects and future needs

Water pipe smoking (WPS), an old method of tobacco smoking, is re-gaining widespread popularity all over the world and among various populations. Smoking machine studies have shown that the water pipe (WP) mainstream smoke (MSS) contains a wide array of chemical substances, many of which are highly toxic and carcinogenic for humans. The concentrations of some substances exceed those present in MSS of cigarettes. Despite being of low grade, current evidence indicates that WPS is associated with different adverse health effects, not only on the respiratory system but also on the cardiovascular, hematological, and reproductive systems, including pregnancy outcomes. In addition, association between WPS and malignancies, such as lung, oral and nasopharyngeal cancer, has been suggested in different studies and systematic reviews. Despite its long standing history, WPS research still harbors a lot of deficiencies. The magnitude of toxicants and carcinogen exposures, effects on human health, as well as the addiction and dependence potentials associated with WPS need to be studied in well-designed prospective trials. Unfortunately, many of the tobacco control and clean indoor policies have exempted water pipes. World wide awareness among the public, smokers, and policymakers about the potential health effects of WPS is urgently required. Furthermore, stringent policies and laws that control and ban WPS in public places, similar to those applied on cigarettes smoking need to be implemented.

Nicotine and carcinogen exposure after water pipe smoking in hookah bars

BACKGROUND

Water pipe tobacco smoking is spreading globally and is increasingly becoming popular in the United States, particularly among young people. Although many perceive water pipe smoking to be relatively safe, clinical experimental studies indicate significant exposures to tobacco smoke carcinogens following water pipe use. We investigated biomarkers of nicotine intake and carcinogen exposure from water pipe smoking in the naturalistic setting of hookah bars.

METHODS

Fifty-five experienced water pipe users were studied before and after smoking water pipe in their customary way in a hookah bar. Urine samples were analyzed for nicotine, cotinine, the tobacco-specific nitrosamine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), and mercapturic acid metabolites of volatile organic compounds (VOC).

RESULTS

We found an average 73-fold increase in nicotine, 4-fold increase in cotinine, 2-fold increase in NNAL, and 14% to 91% increase in VOC mercapturic acid metabolites immediately following water pipe smoking. We saw moderate to high correlations between changes in tobacco-specific biomarkers (nicotine, cotinine, and NNAL) and several mercapturic acid metabolites of VOCs.

CONCLUSION

Water pipe smoking in a hookah bar is associated with significant nicotine intake and carcinogen exposure.

IMPACT

Given the significant intake of nicotine and carcinogens, chronic water pipe use could place users at increased risk of cancer and other chronic diseases. Cancer Epidemiol Biomarkers Prev; 23(6); 1055-66. ©2014 AACR.

Comparison of tobacco-containing and tobacco-free waterpipe products: effects on human alveolar cells

INTRODUCTION

In recent years, a class of products marketed as "tobacco-free" alternatives for the "health conscious user" has become widely available for waterpipe (hookah, narghile, or shisha) smoking. Their adoption may be in part driven by regulations banning tobacco smoking in public places and by an increasing awareness of the hazards of waterpipe tobacco smoking. Although these products are presented in advertising as a "healthier" choice, very little is known about their health effects.

METHODS

In this study, we compared the effects of smoke generated with tobacco-free and conventional tobacco-derived products on human alveolar cells. Smoke was generated with a smoking machine that precisely mimicked the puffing behavior of 15 experienced waterpipe smokers when they used conventional waterpipe tobacco products of their choice and flavor-matched tobacco-free products. Human alveolar epithelial cells (A549) were treated with particulate matter sampled from the smoke, and the effects on cell cycle, proliferation, and doubling time were measured during the subsequent 72hr.

RESULTS

We found that smoke from both types of waterpipe products markedly reduced cell proliferation, caused cell cycle arrest at G0/G1, and increased cell doubling time. There were no significant differences across product in any measure.

CONCLUSION

Tobacco-free and tobacco-based waterpipe products exert substantial and similar deleterious effects on human lung cells. This study adds to the nascent evidence base indicating that except for exposure to nicotine and its derivatives, use of tobacco-free waterpipe products does not present a reduced health risk relative to the use of conventional tobacco-based products.