title: Characterization of Electronic Cigarette Aerosol and Its Induction of Oxidative Stress Response in Oral Keratinocytes.
abstract: In this study, we have generated and characterized Electronic Cigarette (EC) aerosols using a combination of advanced technologies. In the gas phase, the particle number concentration (PNC) of EC aerosols was found to be positively correlated with puff duration whereas the PNC and size distribution may vary with different flavors and nicotine strength. In the liquid phase (water or cell culture media), the size of EC nanoparticles appeared to be significantly larger than those in the gas phase, which might be due to aggregation of nanoparticles in the liquid phase. By using in vitro high-throughput cytotoxicity assays, we have demonstrated that EC aerosols significantly decrease intracellular levels of glutathione in NHOKs in a dose-dependent fashion resulting in cytotoxicity. These findings suggest that EC aerosols cause cytotoxicity to oral epithelial cells in vitro, and the underlying molecular mechanisms may be or at least partially due to oxidative stress induced by toxic substances (e.g., nanoparticles and chemicals) present in EC aerosols.
authors.affiliation: School of Dentistry, University of California Los Angeles, Los Angeles, United States of America.
authors.forename: Eoon Hye
authors.initials: EH
authors.lastname: Ji
authors.affiliation: School of Medicine, Division of Nanomedcine, University of California Los Angeles, Los Angeles, United States of America.
authors.forename: Bingbing
authors.initials: B
authors.lastname: Sun
authors.affiliation: Department of Environmental Health Sciences, University of California Los Angeles, Los Angeles, United States of America.|Peking University, School of Physics, Beijing, China.
authors.forename: Tongke
authors.initials: T
authors.lastname: Zhao
authors.affiliation: Department of Environmental Health Sciences, University of California Los Angeles, Los Angeles, United States of America.
authors.forename: Shi
authors.initials: S
authors.lastname: Shu
authors.affiliation: California Nanosystems Institute, University of California Los Angeles, Los Angeles, United States of America.
authors.forename: Chong Hyun
authors.initials: CH
authors.lastname: Chang
authors.affiliation: School of Dentistry, University of California Los Angeles, Los Angeles, United States of America.
authors.forename: Diana
authors.initials: D
authors.lastname: Messadi
authors.affiliation: School of Medicine, Division of Nanomedcine, University of California Los Angeles, Los Angeles, United States of America.
authors.forename: Tian
authors.initials: T
authors.lastname: Xia
authors.affiliation: Department of Environmental Health Sciences, University of California Los Angeles, Los Angeles, United States of America.
authors.forename: Yifang
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: School of Dentistry, University of California Los Angeles, Los Angeles, United States of America.
authors.forename: Shen
authors.initials: S
authors.lastname: Hu
mesh_terms: D000336:Aerosols; D005978:Glutathione / Q000378:metabolism*; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism* / Q000473:pathology; D009055:Mouth / Q000378:metabolism* / Q000473:pathology; D009538:Nicotine / Q000009:adverse effects / Q000494:pharmacology; D018384:Oxidative Stress; D000072137:Vaping / Q000009:adverse effects*
chemical_list: D000336:Aerosols; D009538:Nicotine; D005978:Glutathione