Exposure to aerosols from electronic nicotine delivery systems (ENDS), or e-cigarettes, has toxic effects on cells important in lung function, according to an NIEHS-funded study.
The researchers exposed human and mouse lung epithelial cells to ENDS aerosol with and without nicotine. Both aerosols resulted in death of both types of exposed cells. Nicotine exposure alone did not cause cell death, but the presence of nicotine in the aerosol significantly increased cell death in human and mouse cells.
To examine effects on mouse immune cells, the researchers exposed a type of cell called a macrophage to ENDS aerosol. Macrophages clear pathogens and dead cells from the body and are important for maintaining healthy lungs. Compared with controls, ENDS-exposed macrophages had increased levels of inflammatory cell death. Rates of death were similar from aerosols with and without nicotine. When exposed to a lower, nonlethal dose of ENDS aerosol, macrophages showed reduced ability to clear away pathogens or dead cells. These reductions were more pronounced when nicotine was present in the ENDS aerosol.
Taken together, these results suggest that ENDS aerosol has toxic effects on cells important in lung function, and that this toxicity is enhanced by the presence of nicotine. These findings highlight the potential danger of ENDS use and should be considered by relevant regulatory bodies, the researchers said.
Citation: Serpa GL, Renton ND, Lee N, Crane MJ, Jamieson AM. 2020. Electronic nicotine delivery system aerosol-induced cell death and dysfunction in macrophages and lung epithelial cells. Am J Respir Cell Mol Biol 63(3):306-316.