Effect of 7, 8-dihydroxyflavone on the up-regulation of Nrf2-mediated heme oxygenase-1 expression in hamster lung fibroblasts

In Vitro Cell Dev Biol Anim. 2014 Jun;50(6):549-54. doi: 10.1007/s11626-014-9735-4. Epub 2014 Mar 8.

Abstract

The cytoprotective mechanism of 7, 8-dihydroxyflavone (DHF) against oxidative stress-induced cell damage with respect to its stimulatory effect on the expression of heme oxygenase-1 (HO-1), a potent antioxidant enzyme, was investigated in the present study. Up-regulation of HO-1 expression by DHF was both dose and time dependent in lung fibroblast V79-4 cells. DHF also increased the protein expression level of the transcription factor nuclear factor erythroid-2-related factor 2 (Nrf2), and induced the translocation of Nrf2 from the cytosol into the nucleus, leading to elevated HO-1 expression. The siNrf2 RNA-transfection attenuated HO-1 expression induced by DHF treatment. In addition, DHF induced the activation of extracellular signal-regulated kinase (ERK), while U0126 (a specific pharmacological inhibitor of ERK kinase) abrogated DHF-activated Nrf2 and HO-1 expression. This suggests that DHF increased the levels of Nrf2 and HO-1 via ERK-dependent pathways. Furthermore, DHF significantly prevented the reduction of cell viability in response to oxidative stress; however, U0126 attenuated the protective effect of DHF. Taken together, these results demonstrate that DHF protected cells from oxidative stress via the activation of an ERK/Nrf2/HO-1 signaling pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus
  • Animals
  • Butadienes / pharmacology
  • Cell Line
  • Cell Nucleus / metabolism
  • Cell Survival
  • Cricetinae
  • Extracellular Signal-Regulated MAP Kinases / antagonists & inhibitors
  • Extracellular Signal-Regulated MAP Kinases / metabolism*
  • Fibroblasts / cytology
  • Fibroblasts / metabolism
  • Flavones / pharmacology*
  • Heme Oxygenase-1 / biosynthesis
  • Heme Oxygenase-1 / genetics
  • Heme Oxygenase-1 / metabolism*
  • Lung / cytology
  • NF-E2-Related Factor 2 / biosynthesis
  • NF-E2-Related Factor 2 / genetics
  • NF-E2-Related Factor 2 / metabolism*
  • Nitriles / pharmacology
  • Oxidative Stress / drug effects*
  • Phosphorylation
  • Protein Transport
  • RNA Interference
  • RNA, Messenger / biosynthesis
  • RNA, Small Interfering
  • Signal Transduction
  • Up-Regulation

Substances

  • 6,7-dihydroxyflavone
  • Butadienes
  • Flavones
  • NF-E2-Related Factor 2
  • Nitriles
  • RNA, Messenger
  • RNA, Small Interfering
  • U 0126
  • Heme Oxygenase-1
  • Extracellular Signal-Regulated MAP Kinases