Protocol to assess the impact of tobacco-induced volatile organic compounds on cardiovascular risk in a cross- sectional cohort: Cardiovascular Injury due to Tobacco Use study

Cardiovascular Health Effects and Synthetic Cooling Agents in E-cigarettes Labeled as 'clear' Marketed in Massachusetts After the Tobacco Product Flavoring Ban

Introduction

Massachusetts (MA) enacted statewide regulation on all flavored tobacco products in June 2020. Thereafter, electronic cigarettes (e-cigarettes) labeled 'clear' emerged on the market. We aimed to combine cardiovascular health effects with chemical analysis of 'clear' e-cigarettes.

Methods

We measured acute changes in blood pressure and heart rate following a 10-minute structured use of participants' own e-cigarette, comparing 'clear' e-cigarette users with other flavored e-cigarette users and non-users. Chemical characterization and quantification of relevant flavorings and cooling agents (WS-3, WS-23) of 19 'clear'-labeled disposable e-cigarette liquids was carried out by GC/MS.

Results

After the ban, participants that used 'clear' labeled e-cigarettes increased from 0% to 21%. Increase in diastolic blood pressure and heart rate was significantly greater in 'clear' e-cigarettes users (n=22) compared to both non-'clear' flavored e-cigarette users (n=114) and non-users (n=72). We saw similar results in heart rate when comparing Juul e-cigarette and 'clear' users; Juul was used as a reference as synthetic coolants WS-3 or WS-23 were not detected in these.All (19/19) 'clear' e-liquids were found to contain synthetic cooling agents WS-23 and/or WS-3, menthol (18/19), as well as other flavorings (12/19).

Discussion

The detected presence of menthol alongside other flavorings in tested 'clear' products is a direct violation of the MA flavored tobacco product regulation, warranting stricter monitoring for new products and constituents. 'clear' e-cigarette use led to greater hemodynamic effects compared to other flavored e-cigarettes and Juul, which raises questions about the effect of cooling agents on users.

Association of electronic cigarette use with circulating angiogenic cell levels in healthy young adults: Evidence for chronic systemic injury

BACKGROUND

Circulating angiogenic cells (CACs) are indicative of vascular health and repair capacity; however, their relationship with chronic e-cigarette use is unclear. This study aims to assess the association between e-cigarette use and CAC levels.

METHODS

We analyzed CAC levels in 324 healthy participants aged 21-45 years from the cross-sectional Cardiovascular Injury due to Tobacco Use study in four groups: never tobacco users (n = 65), sole e-cigarette users (n = 19), sole combustible cigarette users (n = 212), and dual users (n = 28). A total of 15 CAC subpopulations with four cell surface markers were measured using flow cytometry: CD146 (endothelial), CD34 (stem), CD45 (leukocyte), and AC133 (early progenitor/stem). Generalized linear models with gamma distribution and log-link were generated to assess association between CACs and smoking status. Benjamini-Hochberg were used to adjust p-values for multiple comparisons.

RESULTS

The cohort was 47% female, 51% Black/African American, with a mean (± SD) age of 31 ± 7 years. Sole cigarette use was significantly associated with higher levels of two endothelial marker CACs (Q ⩽ 0.05). Dual users had higher levels of four endothelial marker CACs and one early progenitor/stem marker CAC (Q ⩽ 0.05). Sole e-cigarette users had higher levels of one endothelial and one leukocyte marker CAC (Q ⩽ 0.05).

CONCLUSION

Dual use of e-cigarettes and combustible cigarettes was associated with higher levels of endothelial origin CACs, indicative of vascular injury. Sole use of e-cigarettes was associated with higher endothelial and inflammatory CACs, suggesting ongoing systemic injury. Distinct patterns of changes in CAC subpopulations suggest that CACs may be informative biomarkers of changes in vascular health due to tobacco product use.

Pod-based e-liquids impair human vascular endothelial cell function

Pod-based electronic (e-) cigarettes more efficiently deliver nicotine using a protonated formulation. The cardiovascular effects associated with these devices are poorly understood. We evaluated whether pod-based e-liquids and their individual components impair endothelial cell function. We isolated endothelial cells from people who are pod users (n = 10), tobacco never users (n = 7), and combustible cigarette users (n = 6). After a structured use, pod users had lower acetylcholine-mediated endothelial nitric oxide synthase (eNOS) activation compared with never users and was similar to levels from combustible cigarette users (overall P = 0.008, P = 0.01 pod vs never; P = 0.96 pod vs combustible cigarette). The effects of pod-based e-cigarettes and their constituents on vascular cell function were further studied in commercially available human aortic endothelial cells (HAECs) incubated with flavored JUUL e-liquids or propylene glycol (PG):vegetable glycerol (VG) at 30:70 ratio with or without 60 mg/mL nicotine salt for 90 min. A progressive increase in cell death with JUUL e-liquid exposure was observed across 0.0001-1% dilutions; PG:VG vehicle with and without nicotine salt induced cell death. A23187-stimulated nitric oxide production was decreased with all JUUL e-liquid flavors, PG:VG and nicotine salt exposures. Aerosols generated by JUUL e-liquid heating similarly decreased stimulated nitric oxide production. Only mint flavored e-liquids increased inflammation and menthol flavored e-liquids enhanced oxidative stress in HAECs. In conclusion, pod e-liquids and their individual components appear to impair endothelial cell function. These findings indicate the potential harm of pod-based devices on endothelial cell function and thus may be relevant to cardiovascular injury in pod type e-cigarette users.

Urinary volatomic profile of traditional tobacco smokers and electronic cigarettes users as a strategy to unveil potential health issues

Many harmful and potentially harmful constituents are present in tobacco products. Cigarette smoke is known to cause different forms of cancer and trigger the development of chronic diseases. In the last decade, electronic cigarettes have emerged as a healthier alternative associated to less harmful effects in comparison to traditional tobacco. However, the lack of standardization of electronic cigarettes products makes it difficult to establish and compare the real effects on health of products from different manufacturers. To better understand the impact of smoking and vaping, the volatomic composition of urine samples from traditional tobacco smokers and electronic cigarette users was established and compared with nonsmokers (control group), using headspace solid-phase microextraction combined with gas chromatography-mass spectrometry. A total of 45 urinary volatile organic metabolites belonging to different chemical families were identified in the urine of the studied groups. Benzene derivatives, terpenes, and aromatics were the chemical families that contributed the most to the urinary profile of smokers. The vapers urinary volatomic pattern was also dominated by terpenes and aromatics, in addition to alcohols. The orthogonal partial least squares-discriminant analysis of the data obtained indicated that the urinary profile of vapers is more closely related to the control group, reinforcing the hypothesis of the lowest harmfulness of electronic cigarettes. Further studies recruiting a higher number of subjects are therefore necessary to consolidate the data obtained.

Lipid profiles in users of combustible and electronic cigarettes

Electronic cigarette use has especially risen among adolescents and young adults. The aim of this study was to investigate fasting blood glucose and lipid profiles in chronic combustible cigarette and electronic cigarette users. We evaluated participants aged 21 to 45 (n = 525, mean age 31 ± 7 years, 45% women) without established cardiovascular disease or risk factors who were combustible cigarette users (n = 290), electronic cigarette users (n = 131; 65 sole users and 66 dual users), or never users (n = 104). In the first wave of enrollment (2014-2017), electronic cigarette users reported their products as first, second and third generation devices (e-cig users) and were all largely current (i.e., dual) or former (sole) combustible cigarette users, whereas in the second wave of enrollment (2019-2020), electronic cigarette users all reported pod-based device use (pod users) and included more sole users who were never smokers. In multivariable-adjusted analyses comparing to never users, both sole e-cig users and combustible cigarette users had higher glucose and triglycerides and lower high-density lipoprotein (HDL) cholesterol levels. Dual e-cig users showed higher triglycerides and very-low-density lipoprotein cholesterol, and lower HDL cholesterol compared to never users. In contrast, pod users (both sole and dual) had lipid profiles and glucose levels similar to never users. Overall, users of early generation electronic cigarettes display adverse metabolic profiles. In contrast, pod-based electronic cigarette users have similar lipid profiles to never users. Future studies are needed to understand the cumulative effects of electronic cigarette use on cardiometabolic health.

The ultra-structural, metabolomic and metagenomic characterisation of the sudanese smokeless tobacco 'Toombak'

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Toombak, a form of moist smokeless tobacco from Sudan is placed as a dip in the oral cavity most commonly used by males.

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The microbiome of Toombak predominantly consists of the phyla, Firmicutes and Actinobacteria while abundant species include Corynebacterium casei, Atopostipes suicloacalis and Oceanobacillus chironomi.

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High concentrations of iron, volatile aldehydes and tobacco specific nitrosamines were found in Toombak and can lead to toxicity.

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Toombak has a non-homogenous abrasive surface with a high sodium level in the ready to buy form that can damage the oral mucosa.

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New measures must be taken in Sudan to limit harmful compounds in Toombak.

Toombak is a smokeless tobacco produced from the Nicotiana rustica tobacco plant from Sudan. Pre-prepared and ready to buy Toombak samples were analysed using mass spectrometry (heavy metals), gas and liquid chromatography (metabolomics), 16S rRNA metagenomic sequencing (microbiome) and Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) and pH analysis.

Chromium, cobalt, and copper were high in the pre-prepared form of Toombak while iron, tobacco specific nitrosamines (TSNAs), formaldehyde and acetaldehyde were high in both types. Firmicutes and Actinobacteria dominated Toombak. Samples of ready to buy Toombak showed inter-variational differences depending on place of purchase. We found Virgibacillus were increased in the pre-prepared form while Corynebacterium casei, Atopococus tabaci, Atopostipes suicloacalis, Oceanobacillus chironomi and Staphylococcus gallinarum were the most abundant species in the ready to buy forms. PICRUSt analysis highlighted increased activity of metal transport systems in the ready to buy samples as well as an antibiotic transport system. SEM-EDX highlighted large non-homogenous, irregular particles with increased sodium, while pH of samples was in the alkaline range.

The final composition of Toombak is affected by its method of preparation and the end product has the potential to impart many negative consequences on the health of its users. TSNA levels observed in Toombak were some of the highest in the world while the micro-environment of Toombak supports a distinct microbiota profile.

Contemporary Medical Management of Peripheral Artery Disease

Peripheral artery disease (PAD) is a manifestation of systemic atherosclerosis. Modifiable risk factors including cigarette smoking, dyslipidemia, diabetes, poor diet quality, obesity, and physical inactivity, along with underlying genetic factors contribute to lower extremity atherosclerosis. Patients with PAD often have coexistent coronary or cerebrovascular disease, and increased likelihood of major adverse cardiovascular events, including myocardial infarction, stroke and cardiovascular death. Patients with PAD often have reduced walking capacity and are at risk of acute and chronic critical limb ischemia leading to major adverse limb events, such as peripheral revascularization or amputation. The presence of polyvascular disease identifies the highest risk patient group for major adverse cardiovascular events, and patients with prior critical limb ischemia, prior lower extremity revascularization, or amputation have a heightened risk of major adverse limb events. Medical therapies have demonstrated efficacy in reducing the risk of major adverse cardiovascular events and major adverse limb events, and improving function in patients with PAD by modulating key disease determining pathways including inflammation, vascular dysfunction, and metabolic disturbances. Treatment with guideline-recommended therapies, including smoking cessation, lipid lowering drugs, optimal glucose control, and antithrombotic medications lowers the incidence of major adverse cardiovascular events and major adverse limb events. Exercise training and cilostazol improve walking capacity. The heterogeneity of risk profile in patients with PAD supports a personalized approach, with consideration of treatment intensification in those at high risk of adverse events. This review highlights the medical therapies currently available to improve outcomes in patients with PAD.

Relationships among cigarette smoking, urinary biomarkers, and urothelial carcinoma risk: a case-control study

Cigarette smoke is a known risk factor for urothelial carcinoma (UC). However, there is limited information about the distributions and effects of volatile organic compounds (VOCs) on smoking-related UC risk. With this hospital-based case-control study, we explored the associations between urinary levels of cotinine and VOC metabolites (acrylamide, 1,3-butadiene, and benzene) and the risk of UC. Urological examinations and pathological verifications were used to confirm the diagnoses of UC. All study participants provided smoking-related information via questionnaires and face-to-face interviews; they also provided urine samples for the measurement of VOC metabolites, cotinine, and 8-hydroxydeoxyguanosine (8-OHdG), which was used as an indicator of oxidative stress. We applied multiple logistic regression analysis to estimate the risk of UC, and we found that levels of urinary cotinine and 8-OHdG were higher in the UC group than in the control group. Furthermore, urinary levels of VOC metabolites, including N-acetyl-S-(2-carbamoylethyl)-L-cysteine (AAMA), N-acetyl-S-(2-carbamoyl-2-hydroxyethyl)-L-cysteine, N-acetyl-S-(4-hydroxy-2-buten-1-yl)-L-cysteine-3, trans,trans-muconic acid (t,t-MA), and S-phenylmercapturic acid (SPMA), increased with increasing levels of urinary cotinine. After adjusting for potential risk factors, dose-response relationships were observed between UC risk and urinary levels of AAMA, t,t-MA, SPMA, and 8-OHdG. Participants with high urinary levels of cotinine, AAMA, t,t-MA, SPMA, and 8-OHdG had risks of UC that were 3.5- to 6-fold higher than those of participants with lower levels. Future, large-scale investigations of the risks of UC should be explored, and repeated measurement of VOC metabolites should be assessed.

Characterization of Volatile Organic Compound Metabolites in Cigarette Smokers, Electronic Nicotine Device Users, Dual Users, and Nonusers of Tobacco

INTRODUCTION

Limited research exists about the possible cardiovascular effects of electronic nicotine delivery systems (ENDS). We therefore sought to compare exposure to known or potentially cardiotoxic volatile organic compounds (VOCs) in ENDS users, smokers, and dual users.

METHODS

A total of 371 individuals from the Cardiovascular Injury due to Tobacco Use study, a cross-sectional study of healthy participants aged 21-45 years, were categorized as nonusers of tobacco (n = 87), sole ENDS users (n = 17), cigarette smokers (n = 237), and dual users (n = 30) based on 30-day self-reported tobacco product use patterns. Participants provided urine samples for VOC and nicotine metabolite measurement. We assessed associations between tobacco product use and VOC metabolite measures using multivariable-adjusted linear regression models.

RESULTS

Mean (SD) age of the population was 32 (±6.8) years, 55% men. Mean urinary cotinine level in nonusers of tobacco was 2.6 ng/mg creatinine, whereas cotinine levels were similar across all tobacco product use categories (851.6-910.9 ng/mg creatinine). In multivariable-adjusted models, sole ENDS users had higher levels of metabolites of acrolein, acrylamide, acrylonitrile, and xylene compared with nonusers of tobacco, but lower levels of most VOC metabolites compared with cigarette smokers or dual users. In direct comparison of cigarettes smokers and dual users, we found lower levels of metabolites of styrene and xylene in dual users.

CONCLUSION

Although sole ENDS use may be associated with lower VOC exposure compared to cigarette smoking, further study is required to determine the potential health effects of the higher levels of certain reactive aldehydes, including acrolein, in ENDS users compared with nonusers of tobacco.

IMPLICATIONS

ENDS use in conjunction with other tobacco products may not significantly reduce exposure to VOC, but sole use does generally reduce some VOC exposure and warrants more in-depth studies.

Alterations in Vascular Function Associated With the Use of Combustible and Electronic Cigarettes

Background Electronic cigarettes (e-cigarettes) have been proposed as a potential harm reduction tool for combustible cigarette smokers. The majority of adult e-cigarette users continue to smoke combustible cigarettes and are considered dual users. The vascular impact of e-cigarettes remains incompletely defined. Methods and Results We examined the association of e-cigarette use with measures of vascular function and tonometry, preclinical measures of cardiovascular injury. As part of the CITU (Cardiovascular Injury due to Tobacco Use) study, we performed noninvasive vascular function testing in individuals without known cardiovascular disease or cardiovascular disease risk factors who were nonsmokers (n=94), users of combustible cigarettes (n=285), users of e-cigarettes (n=36), or dual users (n=52). In unadjusted analyses, measures of arterial stiffness including carotid-femoral pulse wave velocity, augmentation index, carotid-radial pulse wave velocity, and central blood pressures differed across the use groups. In multivariable models adjusted for age, sex, race, and study site, combustible cigarette smokers had higher augmentation index compared with nonusers (129.8±1.5 versus 118.8±2.7, P=0.003). The augmentation index was similar between combustible cigarette smokers compared with sole e-cigarette users (129.8±1.5 versus 126.2±5.9, P=1.0) and dual users (129.8±1.5 versus 134.9±4.0, P=1.0). Endothelial cells from combustible cigarette smokers and sole e-cigarette users produced less nitric oxide in response to A23187 stimulation compared with nonsmokers, suggestive of impaired endothelial nitric oxide synthase signaling. Conclusions Our findings suggest that e-cigarette use is not associated with a more favorable vascular profile. Future longitudinal studies are needed to evaluate the long-term risks of sustained e-cigarette use.

Atorvastatin enhances endothelial adherens junctions through promoting VE-PTP gene transcription and reducing VE-cadherin-Y731 phosphorylation

Vascular endothelial protein tyrosine phosphatase (VE-PTP) is essential for endothelial cells (ECs) adherens junction and vascular homeostasis; however, the regulatory mechanism of VE-PTP transcription is unknown, and a drug able to promote VE-PTP expression in ECs has not yet been reported in the literature. In this study, we used human ECs as a model to explore small molecule compounds able to promote VE-PTP expression, and found that atorvastatin, a HMG-CoA reductase inhibitor widely used in the clinic to treat hypercholesterolemia-related cardiovascular diseases, strongly promoted VE-PTP transcription in ECs through activating the VE-PTP promoter and upregulating the expression of the transcription factor, specificity protein 1 (SP1). Additionally, atorvastatin markedly reduced VE-cadherin-Y731 phosphorylation induced by cigarette smoke extract and significantly enhanced stability of endothelial adherens junctions. Together, our findings reveal that atorvastatin up-regulates VE-PTP expression, increases VE-cadherin protein levels, and decreases VE-cadherin-Y731 phosphorylation to strengthen EC adherens junctions and maintain vascular cell monolayer integrity, offering a new mechanism of atorvastatin against CSE-induced disruption of vascular integrity and relevant cardio-cerebrovascular disease.