Effects of Electronic (E)-cigarette Vapor and Cigarette Smoke in Cultured Vocal Fold Fibroblasts.

Introduction:
This text presents the findings of a study examining the effects of electronic cigarette (e-cigarette) vapor and conventional cigarette smoke on cultured human vocal fold fibroblasts, the primary cell type of the lamina propria. The study aims to improve understanding of the responses of human vocal fold fibroblasts to e-cigarettes and to establish an in vitro methodology for studying the vocal fold cellular responses to these products.

Key Points:

* The study used an inExpose inhalation exposure system to generate e-cigarette vapor extract (EVE) and cigarette smoke extract (CSE) for exposure to human vocal fold fibroblasts (hVFFs).
* The hVFFs were exposed to EVE derived from commercially available e-liquids without and with increasing concentrations of nicotine, as well as CSE.
* Cellular effects were evaluated by analyzing cytotoxicity, expression of multiple extracellular matrix (ECM) and inflammatory-related genes, and DNa damage.
* Undiluted EVE without and with nicotine reduced the viability of hVFFs to a cytotoxic level, while CSE reduced hVFFs viability to a greater extent than EVE and induced DNa damage.
* No changes in gene expression were observed following EVE or CSE exposure.
* The findings suggest that e-cigarette vapor induces cytotoxicity in hVFFs, but the cellular responses are greater following exposure to CSE, indicating that cigarette smoke may induce more harm, at least in the short term.
* The study forms the basis for an in vitro methodology for future studies of the vocal fold cellular responses to e-cigarettes.

Main Message:
The study highlights the potential negative effects of e-cigarette vapor on human vocal fold fibroblasts, demonstrating cytotoxicity and DNa damage. While the effects of e-cigarette vapor are less severe than conventional cigarette smoke, the findings suggest that e-cigarette use may still pose risks to vocal health. The study provides valuable insights into the cellular responses of vocal fold fibroblasts to e-cigarettes and establishes a foundation for further research in the field. The results emphasize the importance of continued investigation into the potential health risks associated with e-cigarette use, particularly in relation to vocal health.

Martinez JD, Easwaran M, Ramirez D, Erickson-DiRenzo E. Effects of Electronic (E)-cigarette Vapor and Cigarette Smoke in Cultured Vocal Fold Fibroblasts. The Laryngoscope. 2023;133(1):139-146. doi:10.1002/lary.30073