Mild ozonisation activates antioxidant cell response by the Keap1/Nrf2 dependent pathway

Free Radic Biol Med. 2018 Aug 20:124:114-121. doi: 10.1016/j.freeradbiomed.2018.05.093. Epub 2018 Jun 2.

Abstract

Treatment with low-dose ozone is successfully exploited as an adjuvant therapy in the treatment of several disorders. Although the list of medical applications of ozone therapy is increasing, molecular mechanisms underlying its beneficial effects are still partially known. Clinical and experimental evidence suggests that the therapeutic effects of ozone treatment may rely on its capability to mount a beneficial antioxidant response through activation of the nuclear factor erythroid-derived-like 2 (Nrf2) pathway. However, a conclusive mechanistic demonstration is still lacking. Here, we bridge this gap of knowledge by providing evidence that treatment with a low concentration of ozone in cultured cells promotes nuclear translocation of Nrf2 at the chromatin sites of active transcription and increases the expression of antioxidant response element (ARE)-driven genes. Importantly, we show that ozone-induced ARE activation can be reverted by the ectopic expression of the Nrf2 specific inhibitor Kelch-like ECH associated protein (Keap1), thus proving the role of the Nrf2 pathway in the antioxidant response induced by mild ozonisation.

Keywords: Keap1; Nrf2; Oxidative stress; Ozone; Transcription.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antioxidant Response Elements*
  • Antioxidants / metabolism*
  • Cell Nucleus / metabolism
  • Gene Expression Regulation / drug effects*
  • HeLa Cells
  • Humans
  • Kelch-Like ECH-Associated Protein 1 / genetics
  • Kelch-Like ECH-Associated Protein 1 / metabolism*
  • NF-E2-Related Factor 2 / genetics*
  • NF-E2-Related Factor 2 / metabolism
  • Oxidative Stress
  • Ozone / pharmacology*
  • Signal Transduction
  • Transcription, Genetic*

Substances

  • Antioxidants
  • KEAP1 protein, human
  • Kelch-Like ECH-Associated Protein 1
  • NF-E2-Related Factor 2
  • NFE2L2 protein, human
  • Ozone