Effects of condensates from volcanic fumaroles and cigarette smoke extracts on airway epithelial cells.

The impact of volcanic airborne products on airway epithelium homeostasis is largely unknown. This study assessed theeffects of volcanic Fumarole Condensates (FC) alone or combined with Cigarette Smoke Extracts (CSE) on airway epithelialcells (16HBE and A549). Chemical composition of FC was analyzed by gas chromatography and HPLC. Cells were exposedto FC and IL-33 and IL-8 were assessed. The effects of FC and CSE on cell injury were evaluated assessing cell metabolism/cell viability, mitochondrial stress, cell apoptosis/cell necrosis, and cell proliferation. FC contained: water vapor (70-97%),CO 2 (3-30%), acid gases (H 2 S, SO 2 , HCl, HF) around 1%. FC increased the intracellular IL-33 but differently modulatedIL-33 and IL-8 gene expression and IL-8 release in the tested cell lines. FC without/with CSE: (a) increased cell metabo-lism/cell viability in 16HBE, while decreased it in A549; (b) increased mitochondrial stress in both cell types. FC with CSEincreased cell necrosis in A549 in comparison to CSE alone. CSE reduced cell proliferation in 16HB,E while increased itin A549 and FC counteracted these effects in both cell types. Overall, FC induce a pro-inflammatory profile associated to ametabolic reprogramming without a relevant toxicity also in presence of CSE in airway epithelial cells.