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Methods: To assess target organ effects in the lung, we conducted serial bronchoscopy over 4 weeks in 30 never-smokers, randomized either to no intervention or to the use of nicotine- and
flavor-free electronic cigarettes (e-cigs) containing propylene glycol (PG) and vegetable glycerin (VG). Compliance to the e-cig intervention was assessed by urinary PG. Inflammatory cell counts and cytokines were determined in bronchoalveolar lavage (BAL) fluids. Genome-wide expression for microRNA and mRNA changes were determined from bronchial epithelial cells.
Findings: There were no significant differences in changes of inflammatory cell counts or cytokines between baseline and follow-up, comparing the control and e-cig groups. However, an increase in urinary PG, a marker of inhalation-e-cig intake, was significantly correlated with increased cell counts (cell concentrations, macrophages, and lymphocyte) and cytokines (IL-8, IL-13, and TNF-α). There were no significant changes in mRNA or microRNA gene expression.
Interpretation: Although the study is small, it is the first experimental demonstration of an impact of e-cig use on inflammation in the human lung among never-smokers.
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Effects of Electronic Cigarette Use on the Lung: A Clinical Trial by Min-Ae Song, Sarah A. Reisinger, Jo L. Freudenheim, Theodore M. Brasky, Ewy Mathé, Joseph P. McElroy, Quentin A. Nickerson, Daniel Y. Weng, Mark D. Wewers, Peter G. Shields :: SSRN
Nice to see More Research in this area.