Principal Investigator: Zachary T. Bitzer
Funding Mechanism: National Institutes of Health - Grant
ID number: 1K99HL147346-01A1
Award Date: 3/26/2020
Institution: Pennsylvania State University
E-cigarette aerosol contains highly reactive free radicals that can cause oxidative damage, which can contribute to the progression of cancers and other diseases. The goal of this study is to identify these free radicals and use their unique structures to develop an e-cigarette-specific biomarker of exposure. Study aims are: (1) to determine the structures of the free radicals produced by propylene glycol and glycerin in e-cigarettes; and (2) to determine the primary targets of radical adduct formation in the tissue of e-cigarette-exposed mice and identify metabolites formed from radical adducts in the serum. To address Aim 1, researchers will use free radical spin trapping, electron paramagnetic resonance spectroscopy techniques, and mass spectroscopy to identify and analyze the unique structural features of free radicals in e-cigarette aerosol produced from a popular temperature-controlled e-cigarette device. To address Aim 2, 120 mice will be exposed to e-cigarette aerosols and either pre- or post-exposed to 5,5-dimethyl-1-pyrroline noxide (DMPO) spin traps via nose-only exposures. Using an anti-DMPO antibody, the areas of free radical exposure will be observed in the pre-DMPO exposures and targets of radical damage will be observed in the post-DMPO exposures. Radical adducts formed in the post-DMPO exposures will be identified via mass spectroscopy and metabolites of these adducts will be identified in the serum to find viable e-cigarette-specific biomarkers of exposure. Findings may inform future regulatory activities related to e-cigarettes.