title: Noninjurious mechanical ventilation activates a proinflammatory transcriptional program in the lung.
abstract: Mechanical ventilation is a life-saving intervention in patients with respiratory failure. However, human and animal studies have demonstrated that mechanical ventilation using large tidal volumes (>or=12 ml/kg) induces a potent inflammatory response and can cause acute lung injury. We hypothesized that mechanical ventilation with a "noninjurious" tidal volume of 10 ml/kg would still activate a transcriptional program that places the lung at risk for severe injury. To identify key regulators of this transcriptional response, we integrated gene expression data obtained from whole lungs of spontaneously breathing mice and mechanically ventilated mice with computational network analysis. Topological analysis of the gene product interaction network identified Jun and Fos families of proteins as potential regulatory hubs. Electrophoretic mobility gel shift assay confirmed protein binding to activator protein-1 (AP-1) consensus sequences, and supershift experiments identified JunD and FosB as components of ventilation-induced AP-1 binding. Specific recruitment of JunD to the regulatory region of the F3 gene by mechanical ventilation was confirmed by chromatin immunoprecipitation assay. In conclusion, we demonstrate a novel computational framework to systematically dissect transcriptional programs activated by mechanical ventilation in the lung, and show that noninjurious mechanical ventilation initiates a response that can prime the lung for injury from a subsequent insult.
authors.affiliation: Center for Lung Biology, Department of Medicine, University of Washington, Seattle, Washington, USA. sagharib@u.washington.edu
authors.forename: Sina A
authors.initials: SA
authors.lastname: Gharib
authors.forename: W Conrad
authors.initials: WC
authors.lastname: Liles
authors.forename: Lindy S
authors.initials: LS
authors.lastname: Klaff
authors.forename: William A
authors.initials: WA
authors.lastname: Altemeier
mesh_terms: D000818:Animals; D002460:Cell Line; D047369:Chromatin Immunoprecipitation; D016000:Cluster Analysis; D003198:Computer Simulation; D024202:Electrophoretic Mobility Shift Assay; D020869:Gene Expression Profiling; D053263:Gene Regulatory Networks; D018836:Inflammation Mediators / Q000378:metabolism; D008168:Lung / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008957:Models, Genetic; D020411:Oligonucleotide Array Sequence Analysis; D011485:Protein Binding; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics / Q000378:metabolism; D016755:Proto-Oncogene Proteins c-jun; D012121:Respiration, Artificial / Q000379:methods*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013990:Tidal Volume / Q000502:physiology; D018808:Transcription Factor AP-1 / Q000235:genetics / Q000378:metabolism; D055397:Ventilator-Induced Lung Injury / Q000235:genetics* / Q000378:metabolism / Q000503:physiopathology
chemical_list: C483819:Fosb protein, mouse; D018836:Inflammation Mediators; D011518:Proto-Oncogene Proteins; D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; D018808:Transcription Factor AP-1; C528955:junD protein, mouse