Activation of NRF2 Signaling in HEK293 Cells by a First-in-Class Direct KEAP1-NRF2 Inhibitor

J Biochem Mol Toxicol. 2015 Jun;29(6):261-6. doi: 10.1002/jbt.21693. Epub 2015 Feb 12.


Under basal conditions, the antioxidant transcription factor nuclear factor (erythroid-derived 2)-like 2 (NRF2) is bound to the Kelch-like ECH-associated protein 1 (KEAP1) protein and targeted for proteasomal degradation in the cytoplasm. In response to cellular injury or chemical treatment, NRF2 dissociates from KEAP1 and activates the transcription of protective genes and defends against injury. LH601A is a first-in-class direct inhibitor of the KEAP1-NRF2 protein-protein interaction. The purpose of this study was to determine whether LH601A activates NRF2 signaling in human kidney cells. Human embryonic kidney 293 (HEK293) cells were treated with LH601A or the indirect NRF2 activator, sulforaphane (SFN) for 6 or 16 h. SFN and LH601A upregulated NRF2 target genes heme oxygenase-1 (HO-1) (two- to sevenfold), thioredoxin 1 (TRX1) (twofold) and NAD(P)H quinone oxidoreductase 1 (NQO1) mRNAs (twofold). Both compounds also elevated HO-1 and TRX1 protein expression. Since NRF2 activation can protect tissues from injury, LH601A, a direct inhibitor of the KEAP1-NRF2 interaction may be used to defend against kidney injury and/or diseases.

Keywords: HO-1; KEAP1; Kidney; NRF2; Nephrotoxicity.

Publication types

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

MeSH terms

  • Active Transport, Cell Nucleus / drug effects
  • Cell Nucleus / drug effects
  • Cell Nucleus / metabolism
  • Cell Survival / drug effects
  • Dose-Response Relationship, Drug
  • Gene Expression / drug effects
  • HEK293 Cells
  • Humans
  • Intracellular Signaling Peptides and Proteins / antagonists & inhibitors*
  • Isoquinolines / pharmacology*
  • Isothiocyanates / pharmacology
  • Kelch-Like ECH-Associated Protein 1
  • NF-E2-Related Factor 2 / genetics
  • NF-E2-Related Factor 2 / metabolism*
  • Phthalimides / pharmacology*
  • Signal Transduction / drug effects*
  • Sulfoxides


  • Intracellular Signaling Peptides and Proteins
  • Isoquinolines
  • Isothiocyanates
  • KEAP1 protein, human
  • Kelch-Like ECH-Associated Protein 1
  • LH601A
  • NF-E2-Related Factor 2
  • NFE2L2 protein, human
  • Phthalimides
  • Sulfoxides
  • sulforaphane