Send to

Choose Destination
Am J Physiol Lung Cell Mol Physiol. 2019 Nov 6. doi: 10.1152/ajplung.00123.2019. [Epub ahead of print]

Flavored E-liquids Increase Cytoplasmic Ca2+ Levels in Airway Epithelia.

Author information

Cell Biology & Physiology, University of North Carolina at Chapel Hill, United States.
University of North Carolina at Chapel Hill.
Marsico Lung Institute, UNC, United States.
Chemistry, University of North Carolina at Chapel Hill.
Signal Transduction Laboratory, NIEHS, United States.


E-cigarettes are non-combustible, electronic nicotine delivery devices that aerosolize an e-liquid, i.e. nicotine in a propylene glycol/vegetable glycerin (PG/VG) vehicle that also contains flavors. Whilst the effects of nicotine are relatively well-understood, more information is needed regarding the potential biological effects of the other e-liquid constituents. This is a serious concern, because e-liquids are available in over 7,000 distinct flavors. We have previously demonstrated that many e-liquids affect cell growth/viability through an unknown mechanism. Since Ca2+ is a ubiquitous second messenger that regulates cell growth, we therefore characterized the effects of e-liquids on cellular Ca2+ homeostasis. To better understand the extent of this effect, we screened e-liquids for their ability to alter cytosolic Ca2+ levels and found that 42/100 flavored e-liquids elicited a cellular Ca2+ response. Banana Pudding-flavored e-liquid (Banana Pudding), a representative e-liquid from this group, caused phospholipase C activation, ER Ca2+ release, store-operated Ca2+ entry (SOCE) and protein kinase Cα (PKCα) phosphorylation. However, longer Banana Pudding exposures depleted ER Ca2+ stores and inhibited SOCE, suggesting that Banana Pudding may alter Ca2+ homeostasis by both short- and long-term mechanisms. Since dysregulation of Ca2+ signaling can cause chronic inflammation, ER stress and abnormal cell growth, flavored e-cigarette products that can elicit cell Ca2+ responses should be further screened for potential toxicity.


E-cigarette; Orai1; STIM1; Tobacco; nicotine


Supplemental Content

Full text links

Icon for Atypon
Loading ...
Support Center