title: Protein expression profile of rat type two alveolar epithelial cells during hyperoxic stress and recovery.
abstract: In rodent model systems, the sequential changes in lung morphology resulting from hyperoxic injury are well characterized and are similar to changes in human acute respiratory distress syndrome. In the injured lung, alveolar type two (AT2) epithelial cells play a critical role in restoring the normal alveolar structure. Thus characterizing the changes in AT2 cells will provide insights into the mechanisms underpinning the recovery from lung injury. We applied an unbiased systems-level proteomics approach to elucidate molecular mechanisms contributing to lung repair in a rat hyperoxic lung injury model. AT2 cells were isolated from rat lungs at predetermined intervals during hyperoxic injury and recovery. Protein expression profiles were determined by using iTRAQ with tandem mass spectrometry. Of the 959 distinct proteins identified, 183 significantly changed in abundance during the injury-recovery cycle. Gene ontology enrichment analysis identified cell cycle, cell differentiation, cell metabolism, ion homeostasis, programmed cell death, ubiquitination, and cell migration to be significantly enriched by these proteins. Gene set enrichment analysis of data acquired during lung repair revealed differential expression of gene sets that control multicellular organismal development, systems development, organ development, and chemical homeostasis. More detailed analysis identified activity in two regulatory pathways, JNK and miR 374. A novel short time-series expression miner algorithm identified protein clusters with coherent changes during injury and repair. We concluded that coherent changes occur in the AT2 cell proteome in response to hyperoxic stress. These findings offer guidance regarding the specific molecular mechanisms governing repair of the injured lung.
authors.affiliation: MMC 276, 420 Delaware St. SE, Minneapolis, MN 55455. bharg005@umn.edu.
authors.forename: Maneesh
authors.initials: M
authors.lastname: Bhargava
authors.forename: Sanjoy
authors.initials: S
authors.lastname: Dey
authors.forename: Trisha
authors.initials: T
authors.lastname: Becker
authors.forename: Michael
authors.initials: M
authors.lastname: Steinbach
authors.forename: Baolin
authors.initials: B
authors.lastname: Wu
authors.forename: Sang Mee
authors.initials: SM
authors.lastname: Lee
authors.forename: LeeAnn
authors.initials: L
authors.lastname: Higgins
authors.forename: Vipin
authors.initials: V
authors.lastname: Kumar
authors.forename: Peter B
authors.initials: PB
authors.lastname: Bitterman
authors.forename: David H
authors.initials: DH
authors.lastname: Ingbar
authors.forename: Christine H
authors.initials: CH
authors.lastname: Wendt
mesh_terms: D055371:Acute Lung Injury / Q000235:genetics / Q000378:metabolism*; D000465:Algorithms; D000818:Animals; D002478:Cells, Cultured; D004195:Disease Models, Animal; D018496:Hyperoxia / Q000235:genetics / Q000378:metabolism*; D008297:Male; D018384:Oxidative Stress / Q000502:physiology*; D010100:Oxygen / Q000633:toxicity; D040901:Proteomics; D011650:Pulmonary Alveoli / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020545:Respiratory Mucosa / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D059467:Transcriptome
chemical_list: D010100:Oxygen
keywords: acute respiratory distress syndrome; alveolar epithelial cell proteome; bioinformatics; hyperoxia