Hypertonic Saline Primes Activation of the p53-p21 Signaling Axis in Human Small Airway Epithelial Cells That Prevents Inflammation Induced by Pro-inflammatory Cytokines

J Proteome Res. 2016 Oct 7;15(10):3813-3826. doi: 10.1021/acs.jproteome.6b00602. Epub 2016 Aug 29.

Abstract

Uncontrolled inflammatory responses underlie the etiology of acute lung injury and acute distress respiratory syndrome, the most common late complications in trauma, the leading cause of death under the age of 59. Treatment with HTS decreases lung injury in clinical trials, rat models of trauma and hemorrhagic shock and inflammation in lung cell lines, although the mechanisms underlying these responses are still incompletely understood. Transcriptomics (RNaseq), proteomics, and U-13C-glucose tracing metabolomics experiments were performed to investigate the mechanisms of cellular responses to HTS treatment in primary small airway epithelial cells in the presence or absence of inflammatory injury mediated by a cocktail of cytokines (10 ng/mL of IFNγ, IL-1β, and TNFα). Modestly hyperosmolar HTS has an anti-inflammatory effect, triggers the p53-p21 signaling axis, and deregulates mitochondrial metabolism while inducing minimal apoptosis in response to a second hit by cytokines. Decreased transcription of pro-inflammatory cytokines suggested a role for the tumor suppressor protein p53 in mediating the beneficial effects of the HTS treatment. The anti-inflammatory mechanisms induced by HTS involves p53 gene regulation, promotes cell cycle arrest, and prevents ROS formation and mitochondria depolarization. Pharmaceutical targeting of the p53-p21 axis may mimic or reinforce the beneficial effects mediated by HTS when sustained hypertonicity cannot be maintained.

Keywords: RNaseq; metabolomics; mitochondria; osmotic stress; proteomics.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Bronchioles / pathology
  • Cell Cycle Checkpoints / drug effects
  • Cells, Cultured
  • Cyclin-Dependent Kinase Inhibitor p21 / metabolism*
  • Cytokines / physiology
  • Epithelial Cells / drug effects*
  • Epithelial Cells / metabolism
  • Humans
  • Inflammation / prevention & control*
  • Mitochondria / drug effects
  • Mitochondria / metabolism
  • Reactive Oxygen Species / metabolism
  • Saline Solution, Hypertonic / pharmacology*
  • Signal Transduction / drug effects*
  • Tumor Suppressor Protein p53 / metabolism*

Substances

  • Cyclin-Dependent Kinase Inhibitor p21
  • Cytokines
  • Reactive Oxygen Species
  • Saline Solution, Hypertonic
  • TP53 protein, human
  • Tumor Suppressor Protein p53