Reduced biological effect of e-cigarette aerosol compared to cigarette smoke evaluated in vitro using normalized nicotine dose and RNA-seq-based toxicogenomics.
Ontology highlight
ABSTRACT:
SUBMITTER: Haswell LE
PROVIDER: S-EPMC5429854 | biostudies-literature | 2017 Apr
REPOSITORIES: biostudies-literature
Publications
Reduced biological effect of e-cigarette aerosol compared to cigarette smoke evaluated in vitro using normalized nicotine dose and RNA-seq-based toxicogenomics.
Haswell Linsey E LE Baxter Andrew A Banerjee Anisha A Verrastro Ivan I Mushonganono Jessica J Adamson Jason J Thorne David D Gaça Marianna M Minet Emmanuel E
Scientific reports 20170418 1
Electronic cigarettes (e-cigarettes) use has increased globally and could potentially offer a lower risk alternative to cigarette smoking. Here, we assessed the transcriptional response of a primary 3D airway model acutely exposed to e-cigarette aerosol and cigarette (3R4F) smoke. Aerosols were generated with standard intense smoking regimens with careful consideration for dose by normalizing the exposures to nicotine. Two e-cigarette aerosol dilutions were tested for equivalent and higher nicot ...[more]
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Project description:IntroductionTo examine the interaction between an added flavoring (cherry) and nicotine on the perception of electronic cigarette (e-cigarette) aerosol and how this impacts the appeal of flavored liquids for e-cigarette (e-liquids).MethodsA total of 19 subjects (13 male, 6 female) vaped six commercially available e-liquids with varying contents of nicotine (0, 6, 12 mg/mL) and cherry flavor (4.7% or 9.3% vol/vol). For each e-liquid, subjects first rated overall liking/disliking of the aerosol using the Labeled Hedonic Scale, followed by perceived intensities of sweetness, bitterness, harshness (irritation), and cherry flavor of the aerosol using the general version of Labeled Magnitude Scale.ResultsThe main findings were that (1) added nicotine increased perceived irritation and bitterness, and decreased the perceived sweetness of the e-cigarette aerosol; (2) cherry flavoring added a characteristic "cherry flavor" and an increase in the flavoring concentration from 4.7% to 9.3% tended to increase perceived intensities of sweetness, harshness, and bitterness; and (3) hedonic ratings of the e-cigarette aerosol decreased as nicotine level increased, but were not affected by flavor level.ConclusionsOur findings indicate that the appeal of the e-cigarette aerosol decreases as nicotine concentration increases. Conversely, perceived sweetness improved liking. An increase in the concentration of cherry flavoring did not appear to impact any of the measured attributes to a significant degree.ImplicationsThis work demonstrates that the perception of specific sensory attributes of e-cigarettes and their overall appeal are affected by the e-liquid constituents. Most significantly, the results suggest that nicotine decreases the sensory appeal of e-cigarettes by contributing to the perceived irritation and bitterness of the aerosol. These data have implications for the role that nicotine plays in the sensory perception and appeal of e-cigarettes aerosol and further how these sensory factors can be modulated by sweet flavoring.
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