aerosolized nicotine from e-cigarettes alters gene expression, increases lung protein permeability, and impairs viral clearance in murine influenza infection.

Introduction:
This text provides an analysis of the impact of e-cigarette aerosols on respiratory infections, focusing on the effects of nicotine. The study examines the effects of nicotine on host defense mechanisms, viral clearance, and immune activation during influenza infection in mice. The analysis is based on a study conducted by Maishan et al. (2023) published in Frontiers in Immunology.

Key Points:

* The study used a re-fillable tank-style e-cigarette device to isolate the effects of nicotine from other chemical constituents.
* Mice were exposed to e-cigarette aerosols generated from an e-liquid containing VG/PG only or VG/PG with 36 mg/ml nicotine for nine days.
* Exposure to e-cigarette aerosols containing nicotine resulted in increased pro-inflammatory cytokine production in the airspaces prior to infection.
* aerosolized nicotine exposure also caused downregulation of pathways associated with ciliary functions, ion transport, and water balance during influenza infection.
* Nicotine exposure impaired viral clearance and increased lung protein permeability during influenza infection.
* The study found that nicotine exposure caused a marked shift in pulmonary gene expression following influenza infection, characterized by increased pro-inflammatory gene expression and downregulation of genes linked to ciliary function and fluid clearance.
* The study suggests that nicotine has harmful effects during influenza infection in mice and provides a rationale for using viral infection susceptibility as a benchmark in guiding industry regulations and product standards for e-cigarettes.

Main Message:
The study highlights the potential harm of nicotine exposure during respiratory infections. The findings suggest that nicotine impairs host defense mechanisms, viral clearance, and immune activation during influenza infection in mice. The study provides evidence that nicotine exposure can exacerbate lung injury and increase the risk of severe respiratory infections. Therefore, the study emphasizes the need for further research on the impact of e-cigarette aerosols on respiratory infections and the importance of regulating nicotine content in e-cigarette products.

Maishan M, Sarma a, Chun LF, et al. aerosolized nicotine from e-cigarettes alters gene expression, increases lung protein permeability, and impairs viral clearance in murine influenza infection. Frontiers in immunology. 2023;14:1076772. doi:10.3389/fimmu.2023.1076772