Myricetin ameliorated ischemia/reperfusion-induced brain endothelial permeability by improvement of eNOS uncoupling and activation eNOS/NO

J Pharmacol Sci. 2019 May;140(1):62-72. doi: 10.1016/j.jphs.2019.04.009. Epub 2019 May 4.

Abstract

Disruption of the blood-brain barrier (BBB) has been considered as a major pathological change in stroke. eNOS/NO play a key role in maintain BBB function. Myricetin is one of the common flavones widely exists in food and fruit, show certain protective effect on the brain function. This experiment establishes oxygeneglucose deprivation and reoxygenation (OGD/R) brain cell model. The regulated effects of Myricetin on BBB function, eNOS/NO and eNOS uncoupling were evaluated. To investigate the molecular mechanism, Akt and Nrf2 inhibitor were also used. The result showed that Myricetin could significantly decreased the enhancement of endothelial permeability and inflammation in OGD/R model, in addition regulated eNOS/NO pathway. The regulate effect in endothelial permeability and eNOS activity by Myricetin were both decreased when combined with Akt inhibitor or Nrf2 inhibitor, and was abrogated when combined with Akt and Nrf2 inhibitor simultaneously. The regulated effect on eNOS uncoupling by Myricetin were abrogated when combined with Nrf2 inhibitor, but not with Akt inhibitor. In conclusion, Myricetin showed significant protect effect on ischemia/reperfusion-induced brain endothelial permeability, and related to simultaneously regulated Akt pathway and improvement of eNOS uncoupling through Nrf2 pathway.

Keywords: Ischemia/reperfusion injury; Myricetin; eNOS uncoupling; eNOS/NO.

MeSH terms

  • Blood-Brain Barrier / metabolism*
  • Brain / cytology*
  • Brain / metabolism*
  • Brain Ischemia / drug therapy*
  • Brain Ischemia / metabolism
  • Cells, Cultured
  • Endothelial Cells / metabolism*
  • Flavonoids / pharmacology*
  • Flavonoids / therapeutic use*
  • Glucose / metabolism
  • Humans
  • NF-E2-Related Factor 2 / antagonists & inhibitors
  • Nitric Oxide / metabolism*
  • Nitric Oxide Synthase Type III / metabolism*
  • Oxidative Stress / drug effects
  • Permeability / drug effects
  • Phytotherapy*
  • Protective Agents / pharmacology*
  • Protective Agents / therapeutic use*
  • Reperfusion Injury / drug therapy*
  • Reperfusion Injury / metabolism

Substances

  • Flavonoids
  • NF-E2-Related Factor 2
  • NFE2L2 protein, human
  • Protective Agents
  • Nitric Oxide
  • myricetin
  • NOS3 protein, human
  • Nitric Oxide Synthase Type III
  • Glucose