Abstract
Cigarette smoking is the leading cause of preventable deaths worldwide. Electronic Nicotine Delivery Systems (ENDS) may reduce health risks associated with chronic exposure to smoke and their potential benefits have been the matter of intense scientific debate. Here we replicated three key published studies from the Tobacco Industry on cytotoxic and inflammatory effects of cigarette smoke and ENDS aerosol in an independent multicentric study. We aimed to establish the reliability of results and the robustness of conclusions by replicating the authors’ experimental protocols and further validating them with different techniques. We exposed human bronchial epithelial cell (NCI-H292) to cigarette smoke and to aerosol from ENDS. All the exposure were conducted at air-liquid interface to assess cytotoxicity effects of smoke and aerosol. Moreover, we aimed to assess different inflammatory mediators release (IL-6, IL-8 and MMP-1) from cells exposed to whole smoke and to smoke without particulate matter (vapor phase). We were able to replicate the results obtained in the original studies on cytotoxicity confirming that almost 80% of the cytotoxic effect of smoke is due to the vapor phase of smoke. Moreover, our results substantiated the reduced cytotoxic effects of ENDS aerosol in respect to cigarette smoke. However, our data are significantly different from the original ones in terms of inflammatory and remodeling activity triggered by smoke. Taken all together, the data obtained independently in different laboratories clearly demonstrate the reduced toxicity of ENDS products compared to cigarettes and thus providing a valuable tool to the harm reduction strategies in smokers.
Competing Interest Statement
In relation to his work in the area of tobacco control and respiratory diseases, Riccardo Polosa has received lecture fees and research funding from Pfizer, Inc., GlaxoSmithKline plc, CV Therapeutics, NeuroSearch A/S, Sandoz, MSD, Boehringer Ingelheim, Novartis, Duska Therapeutics, and Forest Laboratories. He has also served as a consultant for Pfizer, Inc., Global Health Alliance for treatment of tobacco dependence, CV Therapeutics, NeuroSearch A/S, Boehringer Ingelheim, Duska Therapeutics, Forest Laboratories, ECITA (Electronic Cigarette Industry Trade Association, in the UK), and Health Diplomat (consulting company that delivers solutions to global health problems with special emphasis on harm minimization). Lecture fees from a number of European EC industry and trade associations - including Federation Interprofessionnelle de la VAPE in France and Federazione Italiana Esercenti Svapo Elettronico in Italy- were directly donated to vaper advocacy non-profit organizations. He is currently Head of the European Technical Committee for standardization on - Requirements and test methods for emissions of electronic cigarettes-(CEN/TC 437; WG4). He is also founder of the Center of Excellence for the acceleration of Harm Reduction at the University of Catania (CoEHAR), which has received a grant from the Foundation for a Smoke Free World to support 8 independent investigator-initiated research projects on tobacco harm reduction, and scientific advisor for LIAF, Lega Italiana Anti Fumo (Italian acronym for Italian Anti-Smoking League). Giovanni Li Volti is currently elected Director of the Center of Excellence for the acceleration of HArm Reduction. Konstantinos Poulas has received service grants and research funding from a number of Vaping Companies. He is the Head of the Institute of Research and Innovations, which has received a grant from the Foundation for a Smoke Free World. All the other authors declare no conflicts of interest.
Footnotes
mascaru{at}unict.it; rosalia.emma{at}unict.it; distalfio{at}gmail.com; livolti{at}unict.it; sonja.rust{at}eclatrbc.it; pha2823{at}upnet.gr; kpoulas{at}upatras.gr; fahadz{at}squ.edu.om; toubim{at}squ.edu.om; giordano{at}temple.edu; silvia.boffo{at}temple.edu; drvolarevic{at}yahoo.com; vladislav.volarevic{at}medf.kg.ac.rs; aleksandar{at}medf.kg.ac.rs; pietro.zuccarello{at}unict.it; marfer{at}unict.it; polosa{at}unict.it