Electronic cigarette aerosols induce oxidative stress-dependent cell death and NF-κB mediated acute lung inflammation in mice.

Introduction:
This manuscript reports a study on the toxicity of electronic cigarette (e-cigarette) aerosols and the potential mechanism of lung toxicity. The study generated e-cigarette aerosols by varying the puff numbers, nicotine contents, and collected e-cigarette samples through an impinger system. The collected e-cigarette aerosol samples in terms of particle size, shape, hydrodynamic size, charge, and metal contents were characterized. Their cytotoxic and pro-inflammatory effects on ThP-1 monocyte-differentiated macrophages and BEaS-2B epithelial cells in vitro and acute lung inflammation using NF-κB-luc transgenic mice were tested. In addition, aldehydes, formaldehyde, and reactive oxygen species (ROS) concentration in e-cigarette samples were measured to reveal the potential mechanism of lung toxicity.

Key Points:

* E-cigarette aerosols were generated using a puffing machine and collected through an impinger system.
* The collected e-cigarette aerosol samples were characterized in terms of particle size, shape, hydrodynamic size, charge, and metal contents.
* The cytotoxic and pro-inflammatory effects of e-cigarette aerosols were tested in ThP-1 monocyte-differentiated macrophages and BEaS-2B epithelial cells in vitro.
* E-cigarette aerosols induced acute lung inflammation in NF-κB-luc transgenic mice.
* aldehydes, formaldehyde, and ROS concentration in e-cigarette samples were measured.
* The toxicity of e-cigarette samples was at least partially due to the generation of abiotic ROS and aldehydes during the aerosolization processes by the e-cigarette device.
* The study suggests that oxidative stress, pro-inflammatory pathway activation, and cell death are involved in e-cigarette-induced acute lung inflammation.

Main Message:
This study provides important insights into the toxicity of e-cigarette aerosols and the potential mechanism of lung toxicity. The findings suggest that e-cigarette aerosols can induce acute lung inflammation and cytotoxicity, at least partially due to the generation of abiotic ROS and aldehydes. These results highlight the need for further research to better understand the potential health risks associated with e-cigarette use and to inform regulatory decisions. It is crucial to ensure that the public is informed about the potential risks of e-cigarette use, and that appropriate measures are taken to protect public health.

Ma T, Wang X, Li L, Sun B, Zhu Y, Xia T. Electronic cigarette aerosols induce oxidative stress-dependent cell death and NF-κB mediated acute lung inflammation in mice. archives of toxicology. 2021;95(1):195-205. doi:10.1007/s00204-020-02920-1