Metabolome-wide association study of flavorant vanillin exposure in bronchial epithelial cells reveals disease-related perturbations in metabolism.

Introduction:
This text summarizes a scientific study that investigates the effects of vanillin, a common flavoring agent in electronic cigarettes (e-cig), on metabolism in human bronchial epithelial cells. The study used high-resolution metabolomics and pathway enrichment analysis to understand potential contributing factors to disease by testing for effects of exogenous xenobiotic chemicals, such as vanillin, on metabolism in model systems.

Key Points:

* The study used BEaS-2B cells, a human bronchial epithelial cell line similar to airway lung epithelial cells, which are exposed to e-cig vapors.
* Vanillin concentrations used in the study were within a range expected from e-cig use and also at lower concentrations, as occur from second-hand e-cig exposure.
* Untargeted high-resolution metabolomics with pathway enrichment analysis was used to understand potential contributing factors to disease.
* The study found that vanillin perturbed specific energy, amino acid, antioxidant and sphingolipid pathways previously associated with human disease.
* analysis of a small publicly available human dataset showed associations with several of the same pathways.
* The results suggest that vanillin has potential to be mechanistically important in lung diseases and warrants in vivo toxicity testing in the context of e-cig use.

Main Message:
The study provides evidence that vanillin, a common flavoring agent in e-cig, can perturb specific energy, amino acid, antioxidant and sphingolipid pathways previously associated with human disease. The results suggest that vanillin has potential to be mechanistically important in lung diseases and warrants in vivo toxicity testing in the context of e-cig use. This information is important for regulators to consider when evaluating the safety of e-cig products, as well as for manufacturers to consider when formulating e-liquids.

Smith MR, Jarrell ZR, Orr M, Liu Kh, Go YM, Jones DP. Metabolome-wide association study of flavorant vanillin exposure in bronchial epithelial cells reveals disease-related perturbations in metabolism. Environment international. 2021;147:106323. doi:10.1016/j.envint.2020.106323