Figures
- FIGURE 1
Changes in circulating metabolites induced by daily, chronic inhalation of aerosols generated from multiple e-devices and e-liquids, and for varying exposure durations. Mice were placed in the inExpose system (Scireq) for 1 h daily. Box Mod, vape pen and pod-based e-devices (JUUL) were activated and negative pressure applied to generate fresh e-cigarette aerosols every 20 s, with puff duration of 4 s across all devices. Plasma isolated on the day of harvest underwent comprehensive nontargeted, liquid chromatography–mass spectrometry-based metabolomics to assay thousands of circulating bioactive molecules. a) Venn diagram of significant metabolites (p<0.05) identified in the plasma of mice that inhaled aerosols generated from box Mod e-cigarette devices. No-nicotine aerosols (vehicle) compared to air controls, nicotine-containing aerosols (EV) versus air controls and vehicle versus EV after 12 weeks of daily 1-h exposures. b) Venn diagram of significant metabolites (p<0.05) identified in comparisons among vehicle versus air, EV versus air and vehicle versus EV after 4 weeks of daily box Mod aerosol exposures. c) Venn diagram of unique and shared metabolites across different time exposures (4 versus 12 weeks) for vehicle versus EV. d) Metabolites detected in JUUL mango versus air, JUUL mint versus air and JUUL mango versus JUUL mint after 4 weeks of exposure. The red circle indicates the sole metabolite shared between JUUL mango and JUUL mint exposures: putative β-hydrocortisone (HC). e) Venn diagram of unique and shared metabolites in the setting of lipopolysaccharide (LPS) challenge across air, JUUL mango and JUUL mint exposures. f) Identification of different metabolites across all device types and exposure durations with no overlapping metabolites across e-cigarette exposures. Inhalation of JUUL aerosols caused the smallest metabolite signatures, relative to box Mod and vape pen aerosols. The reduced metabolite signatures may be due to Mod and JUUL devices applying different temperatures and wattages to e-liquids. g) Sex effects on metabolite changes induced by 4 weeks of e-cigarette aerosol exposure, with males and females only having one shared metabolite induced by e-cigarette exposure. Plots were developed using the VennDiagram package in R.
