ASK1 Regulates Bleomycin-induced Pulmonary Fibrosis

Samuel S. Valenca, Brittany E. Dong, Elizabeth M. Gordon, Ramon C. Sun, Christopher M. Waters

Research output: Contribution to journalArticlepeer-review

12 Scopus citations


Pulmonary fibrosis (PF) is an abnormal remodeling of cellular composition and extracellular matrix that results in histological and functional alterations in the lungs. Apoptosis signalregulating kinase-1 (ASK1) is a member of the mitogenactivated protein (MAP) kinase family that is activated by oxidative stress and promotes inflammation and apoptosis. Here we show that bleomycin-induced PF is reduced in Ask1 knockout mice (Ask12/2) compared with wild-type (WT) mice, with improved survival and histological and functional parameters restored to basal levels. In WT mice, bleomycin caused activation of ASK1, p38, and extracellular signalregulated kinase 1/2 (ERK1/2) in lung tissue, as well as changes in redox indicators (thioredoxin and heme-oxygenase-1), collagen content, and epithelial-mesenchymal transition markers (EMTs). These changes were largely restored toward untreated WT control levels in bleomycin-treated Ask12/2 mice. We further investigated whether treatment of WT mice with an ASK1 inhibitor, selonsertib (GS-4997), during the fibrotic phase would attenuate the development of PF. We found that pharmacological inhibition of ASK1 reduced activation of ASK1, p38, and ERK1/2 and promoted the restoration of redox and EMT indicators, as well as improvements in histological parameters. Our results suggest that ASK1 plays a central role in the development of bleomycininduced PF in mice via p38 and ERK1/2 signaling. Together, these data indicate a possible therapeutic target for PF that involves an ASK1/p38/ERK1/2 axis.

Original languageEnglish
Pages (from-to)484-496
Number of pages13
JournalAmerican Journal of Respiratory Cell and Molecular Biology
Issue number5
StatePublished - May 2022

Bibliographical note

Publisher Copyright:
© 2022 American Thoracic Society. All rights reserved.


  • apoptosis signalregulating kinase-1
  • bleomycin
  • pulmonary fibrosis
  • selonsertib

ASJC Scopus subject areas

  • Molecular Biology
  • Pulmonary and Respiratory Medicine
  • Clinical Biochemistry
  • Cell Biology


Dive into the research topics of 'ASK1 Regulates Bleomycin-induced Pulmonary Fibrosis'. Together they form a unique fingerprint.

Cite this