Vaporized E-Cigarette Liquids Induce Ion Transport Dysfunction in Airway Epithelia

Cigarette smoking is associated with chronic obstructive pulmonary disease and chronic bronchitis. Acquired ion transport abnormalities, including CFTR dysfunction, caused by cigarette smoking have been proposed as potential mechanisms for mucus obstruction in chronic bronchitis. Although popular and perceived to be safe, it remains unclear if e-cigarette use harms the airways via mechanisms altering ion transport. Here, we sought to determine if e-cigarette vapor, like cigarette smoke, had the potential to induce acquired CFTR dysfunction, and to what degree. Electrophysiologic methods demonstrated reduced chloride transport caused by vaporized e-cigarette liquid or vegetable glycerin at various exposures (30 min: 57.2% and 14.4% respectively, vs. control, p<0.0001), but not by unvaporized liquid (60 min: 17.6% vs. untreated), indicating that thermal degradation of these products is required to induce the observed defects. We also observed reduced ATP-dependent responses (-10.8±3.0 vs. -18.8±5.1 µA/cm2 c...