Oxidative stress induced by electronic nicotine delivery systems (ENDS): Focus on respiratory system

Electronic Nicotine Delivery Systems and Cardiovascular/Cardiometabolic Health

The use of electronic nicotine delivery systems, specifically electronic cigarettes (e-cig), has risen dramatically within the last few years; the demographic purchasing these devices is now predominantly adolescents that are not trying to quit the use of traditional combustible cigarettes, but rather are new users. The composition and appearance of these devices has changed since their first entry into the market in the late 2000s, but they remain composed of a battery and aerosol delivery system that is used to deliver breakdown products of propylene glycol/vegetable glycerin, flavorings, and potentially nicotine or other additives. Manufacturers have also adjusted the type of nicotine that is used within the liquid to make the inhalation more palatable for younger users, further affecting the number of youth who use these devices. Although the full spectrum of cardiovascular and cardiometabolic consequences of e-cig use is not fully appreciated, data is beginning to show that e-cigs can cause both short- and long-term issues on cardiac function, vascular integrity and cardiometabolic issues. This review will provide an overview of the cardiovascular, cardiometabolic, and vascular implications of the use of e-cigs, and the potential short- and long-term health effects. A robust understanding of these effects is important in order to inform policy makers on the dangers of e-cigs use.

Different Effects of Cigarette Smoke, Heated Tobacco Product and E-Cigarette Vapour on Orbital Fibroblasts in Graves' Orbitopathy; a Study by Real Time Cell Electronic Sensing

Thyroid autoimmunity in Graves’ disease (GD) is accompanied by Graves’ orbitopathy (GO) in 40% of the cases. Orbital fibroblasts (OF) play a key role in the pathogenesis and cigarette smoking is a known deteriorating factor. Alongside conventional cigarettes (CC) new alternatives became available for smokers, including heated tobacco products (HTP) and E-cigarettes (ECIG). We aimed to study the cellular effects of smoke extracts (SE) in orbital fibroblasts. Primary OF cultures from GO and NON-GO orbits were exposed to different concentrations of SE (1%, 50%) and the changes were followed using Real Time Cell Electronic Sensing (RT-CES). Untreated GO and NON-GO cells had different maximum cell index (CI) values of 3.3 and 2.79 respectively (p < 0.0001). CC, HTP and ECIG treated NON-GO fibroblasts exhibited peak CIs of 2.62, 3.32 and 3.41 while treated GO cells’ CIs were higher, 5.38, 6.25 and 6.33, respectively (p < 0.0001). The metabolic activity (MTT) decreased (p < 0.001) and hyaluronan production doubled (p < 0.02) after 50% of CC SE treatment in all cell cultures. GO fibroblasts were more sensitive to low concentration SE then NON-GO fibroblasts (p < 0.0001). The studied SEs exerted different effects. RT-CES is a sensitive technique to detect the effects of very low concentration of SE on fibroblasts.

Electronic nicotine delivery system design and aerosol toxicants: A systematic review

BACKGROUND

Electronic nicotine delivery systems (ENDS; e-cigarettes), consisting of a battery, heating element and e-liquid, have evolved significantly with wide variation in design, components, operating powers, and chemical constituents. Generated aerosols have been reported to contain potentially toxic substances. We conducted a systematic review to assess what is known about the presence of toxicants in ENDS aerosols in order to inform how system design could mitigate risk.

METHODS

Articles reporting on or evaluating design characteristics of ENDS and aerosol constituents were included and summarized.

RESULTS

The search identified 2,305 articles, of which 92 were included after full-text review. Findings were grouped into 6 major categories of potentially harmful chemicals: carbonyls, volatile organic chemicals, trace elements, reactive oxygen species and free radicals, polycyclic aromatic hydrocarbons, and tobacco-specific nitrosamines. In general, higher concentrations of aerosol toxicants are associated with increased power or voltage. Aerosol toxicants are also associated with e-liquid flavoring agents existing as primary ingredients or as products of thermal degradation.

CONCLUSIONS

Improved ENDS design can reduce toxicant levels. Additional research is needed to develop a framework for optimizing system characteristics to minimize exposure, especially with respect to heating power and e-liquids. Both manufacturers and regulatory agencies have roles in reducing toxicants and potential health risks from ENDS.

Effects of Exposure to Tobacco Cigarette, Electronic Cigarette and Heated Tobacco Product on Adipocyte Survival and Differentiation In Vitro

Cigarette smoking (CS) causes significant morbidity worldwide, attributed to the numerous toxicants generated by tobacco combustion. Electronic cigarettes (ECIG) and heated tobacco products (HTP) are considered alternative smoking/vaping products that deliver nicotine through an inhaled aerosol and emit fewer harmful constituents than CS. However, their long-term impacts on human health are not well established. Nicotine exposure has been linked to lipolysis and body weight loss, while smoking has been associated with insulin resistance and hyperinsulinemia. Enhanced function of beige (thermogenic) adipocytes has been proposed as a means to reduce obesity and metabolic disorders. In this study, we compared the effect of extract-enriched media via exposure of culture medium to CS, HTP aerosol, and ECIG aerosol on the viability and the differentiation of 3T3-L1 pre-adipocytes to beige adipocytes. Only CS extract caused a decrease in cell viability in a dose- and time-dependent manner. Furthermore, relative lipid accumulation and expression levels of the adipocyte markers Pgc-1α, Ppar-γ and Resistin were significantly decreased in cells exposed to CS extract. Our results demonstrate that CS extract, in contrast to HTP and ECIG extracts, significantly impairs differentiation of pre-adipocytes to beige adipocytes and may therefore impact significantly adipose tissue metabolic function.