Nrf2 Activation by 5-lipoxygenase Metabolites in Human Umbilical Vascular Endothelial Cells

Nutrients. 2017 Sep 11;9(9):1001. doi: 10.3390/nu9091001.


5-hydroxyeicosatetraenoic acid (5-HETE) and 5-hydroxyeicosapentaenoic acid (5-HEPE) are major metabolites produced by 5-lipoxygenase (5-LOX) from arachidonic acid (AA) and eicosapentaenoic acid (EPA). Effects of hydroxides on endothelial cells are unclear, although 5-LOX is known to increase at arteriosclerotic lesions. To investigate the effects of hydroxides on human umbilical vein endothelial cells (HUVECs), the cells were treated with 50 μM each of AA, EPA, 5-HETE, and 5-HEPE. Treatment of HUVECs with 5-HETE and 5-HEPE, rather than with AA and EPA, increased the nuclear translocation of NF-E2 related factor 2 (Nrf2) and upregulated the expression of heme oxygenase-1 and cystine/glutamate transporter regulated by Nrf2. Reactive oxygen species (ROS) generation was markedly elevated in HUVECs after treatment with 5-HETE and 5-HEPE, and the pretreatment with α-tocopherol abrogated ROS levels similar to those in the vehicle control. However, ROS generation was independent of Nrf2 activation induced by 5-HETE and 5-HEPE. 5-HETE was converted to 5-oxo-eicosatetraenoic acid (5-oxo-ETE) in HUVECs, and 5-oxo-ETE increased Nrf2 activation. These results suggest that 5-HETE works as an Nrf2 activator through the metabolite 5-oxo-ETE in HUVECs. Similarly, 5-HEPE works in the same way, because 5-HEPE is metabolized to 5-oxo-eicosapentaenoic acid through the same pathway as that for 5-HETE.

Keywords: 5-hydroxyeicosapentaenoic acid; 5-hydroxyeicosatetraenoic acid; 5-lipoxygenase; 5-oxo-eicosatetraenoic acid; Nrf2; human umbilical vein endothelial cells; reactive oxygen species.

MeSH terms

  • Arachidonate 5-Lipoxygenase / metabolism*
  • Arachidonic Acid / metabolism
  • Cells, Cultured
  • Eicosapentaenoic Acid / analogs & derivatives
  • Eicosapentaenoic Acid / pharmacology
  • Heme Oxygenase-1 / metabolism
  • Human Umbilical Vein Endothelial Cells / metabolism*
  • Humans
  • Hydroxyeicosatetraenoic Acids / pharmacology
  • NF-E2-Related Factor 2 / genetics
  • NF-E2-Related Factor 2 / metabolism*
  • Reactive Oxygen Species / metabolism
  • alpha-Tocopherol / pharmacology


  • Hydroxyeicosatetraenoic Acids
  • NF-E2-Related Factor 2
  • NFE2L2 protein, human
  • Reactive Oxygen Species
  • Arachidonic Acid
  • 5-hydroxy-6,8,11,14-eicosatetraenoic acid
  • 5-hydroxy-6,8,11,14,17-eicosapentaenoic acid
  • Eicosapentaenoic Acid
  • Arachidonate 5-Lipoxygenase
  • HMOX1 protein, human
  • Heme Oxygenase-1
  • alpha-Tocopherol