A comparative assessment of e-cigarette aerosols and cigarette smoke on in vitro endothelial cell migration

Abstract

Cigarette smoking is a risk factor for several diseases. There has been a steep increase in the use of e-cigarettes that may offer a safer alternative to cigarette smoking. In vitro models of smoking-related diseases may provide valuable insights into disease mechanisms associated with tobacco use and could be used to assess e-cigarettes. We previously reported the application of a 'scratch wound' assay, measuring endothelial cell migration rate following artificial wounding, in the presence or absence of cigarette smoke extracts. This study reports the comparative effects of two commercial e-cigarette products (Vype ePen and Vype eStick) and a scientific reference cigarette (3R4F) on endothelial migration in vitro. Puff-matched extracts were generated using the Health Canada Intense (HCI) regime for cigarettes and a modified HCI for e-cigarettes. Exposure to 3R4F extract (20h) induced concentration-dependent inhibition of endothelial cell migration, with complete inhibition at concentrations >20%. E-cigarette extracts did not inhibit migration, even at double the 3R4F extract nicotine concentration, allowing cells to migrate into the wounded area. Our data demonstrate that e-cigarettes do not induce the inhibition of endothelial cell migration in vitro when compared to 3R4F. The scratch wound assay enables the comparative assessment between tobacco and nicotine products in vitro.

The in vitro assessment of a novel vaping technology

“…The scratch wound assay, as previously described [ 10 ] was utilised to detect and measure endothelial migration rates in vitro following exposure to AqE from test products. In brief, a scratch wound was made on confluent human umbilical vein endothelial cell (HUVEC) monolayers in 96-well ImageLock plates (Essen Instruments, Ann Arbor, MI, USA) using a WoundMaker apparatus (Essen Instruments).…”

“…In the interim, data from analytical chemistry of aerosol emissions, as well as preclinical and clinical assessment of the effects of exposure to these aerosols, will greatly enhance our understanding of the potential for these products to be less risky to the consumer. In vitro data suggest that e-cig aerosol exposure has reduced toxicological effects on lung [ [5] , [6] , [7] , [8] ] and cardiovascular cells [ 9 , 10 ], as well as inducing little to no activity in traditional genetic toxicology assessments [ 11 , 12 ].…”

“…This was complemented with contemporary high content screening (HCS) approaches to assess targeted endpoints related to cell health and early indicators of biological effects such as cellular and oxidative stress, as previously described [ 21 ]. Endothelial wound repair was also assessed following treatment with e-cig aerosol, as this endpoint has previously been found to be inhibited by combustible cigarette smoke [ 10 ]. In addition, the cytotoxicity of the whole aerosol itself was assessed by direct exposure of human lung cells at the air-liquid interface using our in vitro exposure systems [ 22 ].…”

Immunological and pathological effects of electronic cigarettes

“…CS suppressed HUVEC migration dose‐dependently but ECVE did not exert this effect . The abundance of oxidants and free radicals in CS can lead to oxidative damage, apoptosis and necrosis in endothelium, and this paper, in contrast, proposed that E‐cigarette use may reduce the risk of CVD by reducing exposure to oxidant species in users . Myocardial cells are another example of cells in which oxidative stress is induced by CS.…”

Efectos sobre la salud de los cigarrillos electrónicos. Una revisión de la literatura

“…Se han realizado estudios en poblaciones, cultivos celulares y animales. Los estudios en células tumorales no diferenciadas documentaron la relación entre la disfunción y daño endotelial producido por el CC, sin embargo, se encontró que los CE no produjeron ningún tipo de inhibición de migración endotelial con el doble de concentración de nicotina (41,42).…”