title: The impact of oil spill to lung health--Insights from an RNA-seq study of human airway epithelial cells.
abstract: The Deepwater Horizon oil spill (BP oil spill) in the Gulf of Mexico was a unique disaster event, where a huge amount of oil spilled from the sea bed and a large volume of dispersants were applied to clean the spill. The operation lasted for almost 3 months and involved >50,000 workers. The potential health hazards to these workers may be significant as previous research suggested an association of persistent respiratory symptoms with exposure to oil and oil dispersants. To reveal the potential effects of oil and oil dispersants on the respiratory system at the molecular level, we evaluated the transcriptomic profile of human airway epithelial cells grown under treatment of crude oil, the dispersants Corexit 9500 and Corexit 9527, and oil-dispersant mixtures. We identified a very strong effect of Corexit 9500 treatment, with 84 genes (response genes) differentially expressed in treatment vs. control samples. We discovered an interactive effect of oil-dispersant mixtures; while no response gene was found for Corexit 9527 treatment alone, cells treated with Corexit 9527+oil mixture showed an increased number of response genes (46 response genes), suggesting a synergic effect of 9527 with oil on airway epithelial cells. Through GO (gene ontology) functional term and pathway-based analysis, we identified upregulation of gene sets involved in angiogenesis and immune responses and downregulation of gene sets involved in cell junctions and steroid synthesis as the prevailing transcriptomic signatures in the cells treated with Corexit 9500, oil, or Corexit 9500+oil mixture. Interestingly, these key molecular signatures coincide with important pathological features observed in common lung diseases, such as asthma, cystic fibrosis and chronic obstructive pulmonary disease. Our study provides mechanistic insights into the detrimental effects of oil and oil dispersants to the respiratory system and suggests significant health impacts of the recent BP oil spill to those people involved in the cleaning operation.
authors.affiliation: Dept. of Biostatistics and Bioinformatics, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA. Electronic address: yliu8@tulane.edu.
authors.forename: Yao-Zhong
authors.initials: YZ
authors.lastname: Liu
authors.affiliation: Dept. of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA; Tulane Cancer Center, Tulane University, New Orleans, LA, USA.
authors.forename: Astrid M
authors.initials: AM
authors.lastname: Roy-Engel
authors.affiliation: Tulane Cancer Center, Tulane University, New Orleans, LA, USA; Dept. of Pathology, Tulane University School of Medicine, New Orleans, LA, USA.
authors.forename: Melody C
authors.initials: MC
authors.lastname: Baddoo
authors.affiliation: Tulane Cancer Center, Tulane University, New Orleans, LA, USA; Dept. of Pathology, Tulane University School of Medicine, New Orleans, LA, USA.
authors.forename: Erik K
authors.initials: EK
authors.lastname: Flemington
authors.affiliation: Dept. of Chemistry, Xavier University of Louisiana, New Orleans, LA, USA.
authors.forename: Guangdi
authors.initials: G
authors.lastname: Wang
authors.affiliation: Dept. of Chronic Respiratory Diseases, School of Health Sciences, University of Newcastle, Callaghan, Australia. Electronic address: he.wang@newcastle.edu.au.
authors.forename: He
authors.initials: H
authors.lastname: Wang
mesh_terms: D001980:Bronchi / Q000166:cytology* / Q000187:drug effects; D002478:Cells, Cultured; D004357:Drug Synergism; D004847:Epithelial Cells / Q000187:drug effects*; D015870:Gene Expression / Q000187:drug effects*; D005786:Gene Expression Regulation / Q000187:drug effects; D063990:Gene Ontology; D006801:Humans; D008055:Lipids / Q000009:adverse effects; D059392:Petroleum Pollution / Q000009:adverse effects*; D017423:Sequence Analysis, RNA / Q000379:methods*
chemical_list: D008055:Lipids; C470995:corexit 9500; C021984:corexit 9527
keywords: Airway epithelial cells; BP oil spill; Lung health; Oil dispersants; RNA-seq