title: Transcriptome sequencing reveals e-cigarette vapor and mainstream-smoke from tobacco cigarettes activate different gene expression profiles in human bronchial epithelial cells.
abstract: Electronic cigarettes (e-cigarettes) generate an aerosol vapor (e-vapor) thought to represent a less risky alternative to main stream smoke (MSS) of conventional tobacco cigarettes. RNA-seq analysis was used to examine the transcriptomes of differentiated human bronchial epithelial (HBE) cells exposed to air, MSS from 1R5F tobacco reference cigarettes, and e-vapor with and without added nicotine in an in vitro air-liquid interface model for cellular exposure. Our results indicate that while e-vapor does not elicit many of the cell toxicity responses observed in MSS-exposed HBE cells, e-vapor exposure is not benign, but elicits discrete transcriptomic signatures with and without added nicotine. Among the cellular pathways with the most significantly enriched gene expression following e-vapor exposure are the phospholipid and fatty acid triacylglycerol metabolism pathways. Our data suggest that alterations in cellular glycerophopholipid biosynthesis are an important consequences of e-vapor exposure. Moreover, the presence of nicotine in e-vapor elicits a cellular response distinct from e-vapor alone including alterations of cytochrome P450 function, retinoid metabolism, and nicotine catabolism. These studies establish a baseline for future analysis of e-vapor and e-vapor additives that will better inform the FDA and other governmental bodies in discussions of the risks and future regulation of these products.
authors.affiliation: Research Center for Air Pollution and Health and Institute of Crop Science, Zhejiang University, Hangzhou 310058, China.
authors.forename: Yifei
authors.initials: Y
authors.lastname: Shen
authors.affiliation: Department of Biology, University of Virginia, Charlottesville, VA 22903, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Wolkowicz
authors.affiliation: Department of Biology, University of Virginia, Charlottesville, VA 22903, USA.
authors.forename: Tatyana
authors.initials: T
authors.lastname: Kotova
authors.affiliation: Research Center for Air Pollution and Health and Institute of Crop Science, Zhejiang University, Hangzhou 310058, China.
authors.forename: Lonjiang
authors.initials: L
authors.lastname: Fan
authors.affiliation: Department of Biology, University of Virginia, Charlottesville, VA 22903, USA.|Department of Public Health Sciences, University of Virginia, Charlottesville, VA 22903, USA.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Timko
mesh_terms: D000336:Aerosols / Q000009:adverse effects / Q000032:analysis; D001980:Bronchi / Q000166:cytology* / Q000187:drug effects; D066300:Electronic Nicotine Delivery Systems / Q000009:adverse effects*; D004847:Epithelial Cells / Q000187:drug effects*; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods*; D005786:Gene Expression Regulation / Q000187:drug effects; D053263:Gene Regulatory Networks / Q000187:drug effects; D006801:Humans; D017423:Sequence Analysis, RNA / Q000379:methods*; D012906:Smoke / Q000009:adverse effects*; D062789:Tobacco Products
chemical_list: D000336:Aerosols; D012906:Smoke