title: Hyperosmolarity invokes distinct anti-inflammatory mechanisms in pulmonary epithelial cells: evidence from signaling and transcription layers.
abstract: Hypertonic saline (HTS) has been used intravenously to reduce organ dysfunction following injury and as an inhaled therapy for cystic fibrosis lung disease. The role and mechanism of HTS inhibition was explored in the TNFα and IL-1β stimulation of pulmonary epithelial cells. Hyperosmolar (HOsm) media (400 mOsm) inhibited the production of select cytokines stimulated by TNFα and IL-1β at the level of mRNA translation, synthesis and release. In TNFα stimulated A549 cells, HOsm media inhibited I-κBα phosphorylation, NF-κB translocation into the nucleus and NF-κB nuclear binding. In IL-1β stimulated cells HOsm inhibited I-κBα phosphorylation without affecting NF-κB translocation or nuclear binding. Incubation in HOsm conditions inhibited both TNFα and IL-1β stimulated nuclear localization of interferon response factor 1 (IRF-1). Additional transcription factors such as AP-1, Erk-1/2, JNK and STAT-1 were unaffected by HOsm. HTS and sorbitol supplemented media produced comparable outcomes in all experiments, indicating that the effects of HTS were mediated by osmolarity, not by sodium. While not affecting MAPK modules discernibly in A549 cells, both HOsm conditions inhibit IRF-1 against TNFα or IL-1β, but inhibit p65 NF-kB translocation only against TNFα but not IL-1β. Thus, anti-inflammatory mechanisms of HTS/HOsm appear to disrupt cytokine signals at distinct intracellular steps.
authors.affiliation: Department of Surgery/Trauma Research Center, University of Colorado Denver, Aurora, Colorado, United States of America.
authors.forename: Franklin L
authors.initials: FL
authors.lastname: Wright
authors.affiliation: Department of Surgery/Trauma Research Center, University of Colorado Denver, Aurora, Colorado, United States of America.
authors.forename: Fabia
authors.initials: F
authors.lastname: Gamboni
authors.affiliation: Department of Surgery, Denver Health Medical Center, Denver, Colorado, United States of America.
authors.forename: Ernest E
authors.initials: EE
authors.lastname: Moore
authors.affiliation: Department of Surgery/Trauma Research Center, University of Colorado Denver, Aurora, Colorado, United States of America.
authors.forename: Trevor L
authors.initials: TL
authors.lastname: Nydam
authors.affiliation: Department of Surgery/Trauma Research Center, University of Colorado Denver, Aurora, Colorado, United States of America.
authors.forename: Sanchayita
authors.initials: S
authors.lastname: Mitra
authors.affiliation: Department of Pediatrics, University of Colorado Denver, Aurora, Colorado, United States of America.
authors.forename: Christopher C
authors.initials: CC
authors.lastname: Silliman
authors.affiliation: Department of Surgery/Trauma Research Center, University of Colorado Denver, Aurora, Colorado, United States of America.
authors.forename: Anirban
authors.initials: A
authors.lastname: Banerjee
mesh_terms: D002460:Cell Line; D004847:Epithelial Cells / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D053583:Interleukin-1beta / Q000378:metabolism*; D008168:Lung / Q000378:metabolism* / Q000503:physiopathology; D016328:NF-kappa B / Q000235:genetics; D010766:Phosphorylation; D012462:Saline Solution, Hypertonic / Q000008:administration & dosage; D015398:Signal Transduction / Q000235:genetics; D051996:Transcription Factor RelA; D014158:Transcription, Genetic; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*
chemical_list: D053583:Interleukin-1beta; D016328:NF-kappa B; D012462:Saline Solution, Hypertonic; D051996:Transcription Factor RelA; D014409:Tumor Necrosis Factor-alpha