title: Lung transcriptional profiling: insights into the mechanisms of ozone-induced pulmonary injury in Wistar Kyoto rats.
abstract: Acute ozone-induced pulmonary injury and inflammation are well characterized in rats; however, mechanistic understanding of the pathways involved is limited. We hypothesized that acute exposure of healthy rats to ozone will cause transcriptional alterations, and comprehensive analysis of these changes will allow us to better understand the mechanism of pulmonary injury and inflammation. Male Wistar Kyoto rats (10-12 week) were exposed to air, or ozone (0.25, 0.5 or 1.0 ppm) for 4 h and pulmonary injury and inflammation were assessed at 0-h or 20-h (n = 8/group). Lung gene expression profiling was assessed at 0-h (air and 1.0 ppm ozone, n = 3-4/group). At 20-h bronchoalveolar lavage, fluid protein and neutrophils increased at 1 ppm ozone. Numerous genes involved in acute inflammatory response were up-regulated along with changes in genes involved in cell adhesion and migration, steroid metabolism, apoptosis, cell cycle control and cell growth. A number of NRF2 target genes were also induced after ozone exposure. Based on expression changes, Rela, SP1 and TP3-mediated signaling were identified to be mediating downstream changes. Remarkable changes in the processes of endocytosis provide the insight that ozone-induced lung injury and inflammation are likely initiated by changes in cell membrane components and receptors likely from oxidatively modified lung lining lipids and proteins. In conclusion, ozone-induced injury and inflammation are preceded by changes in gene targets for cell adhesion/migration, apoptosis, cell cycle control and growth regulated by Rela, SP1 and TP53, likely mediated by the process of endocytosis and altered steroid receptor signaling.
authors.affiliation: a Research Cores Unit and.
authors.forename: William O
authors.initials: WO
authors.lastname: Ward
authors.affiliation: b Environmental Public Health Division , National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency , Research Triangle Park , NC , USA.
authors.forename: Allen D
authors.initials: AD
authors.lastname: Ledbetter
authors.affiliation: b Environmental Public Health Division , National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency , Research Triangle Park , NC , USA.
authors.forename: Mette C
authors.initials: MC
authors.lastname: Schladweiler
authors.affiliation: b Environmental Public Health Division , National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency , Research Triangle Park , NC , USA.
authors.forename: Urmila P
authors.initials: UP
authors.lastname: Kodavanti
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation / Q000187:drug effects; D019570:Inhalation Exposure; D008168:Lung / Q000378:metabolism*; D055370:Lung Injury / Q000139:chemically induced* / Q000378:metabolism; D008297:Male; D010126:Ozone / Q000008:administration & dosage / Q000633:toxicity*; D012313:RNA / Q000235:genetics / Q000378:metabolism; D051381:Rats; D011921:Rats, Inbred WKY; D014158:Transcription, Genetic / Q000502:physiology*; D059467:Transcriptome
chemical_list: D000393:Air Pollutants; D012313:RNA; D010126:Ozone
keywords: Air pollution; Wistar Koto rats; lung injury; ozone; transcriptional profiling