Mitochondria-targeted esculetin alleviates mitochondrial dysfunction by AMPK-mediated nitric oxide and SIRT3 regulation in endothelial cells: potential implications in atherosclerosis

Sci Rep. 2016 Apr 11:6:24108. doi: 10.1038/srep24108.

Abstract

Mitochondria-targeted compounds are emerging as a new class of drugs that can potentially alter the pathophysiology of those diseases where mitochondrial dysfunction plays a critical role. We have synthesized a novel mitochondria-targeted esculetin (Mito-Esc) with an aim to investigate its effect during oxidative stress-induced endothelial cell death and angiotensin (Ang)-II-induced atherosclerosis in ApoE(-/-) mice. Mito-Esc but not natural esculetin treatment significantly inhibited H2O2- and Ang-II-induced cell death in human aortic endothelial cells by enhancing NO production via AMPK-mediated eNOS phosphorylation. While L-NAME (NOS inhibitor) significantly abrogated Mito-Esc-mediated protective effects, Compound c (inhibitor of AMPK) significantly decreased Mito-Esc-mediated increase in NO production. Notably, Mito-Esc promoted mitochondrial biogenesis by enhancing SIRT3 expression through AMPK activation; and restored H2O2-induced inhibition of mitochondrial respiration. siSIRT3 treatment not only completely reversed Mito-Esc-mediated mitochondrial biogenetic marker expressions but also caused endothelial cell death. Furthermore, Mito-Esc administration to ApoE(-/-) mice greatly alleviated Ang-II-induced atheromatous plaque formation, monocyte infiltration and serum pro-inflammatory cytokines levels. We conclude that Mito-Esc is preferentially taken up by the mitochondria and preserves endothelial cell survival during oxidative stress by modulating NO generation via AMPK. Also, Mito-Esc-induced SIRT3 plays a pivotal role in mediating mitochondrial biogenesis and perhaps contributes to its anti-atherogenic effects.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AMP-Activated Protein Kinases / antagonists & inhibitors
  • AMP-Activated Protein Kinases / metabolism*
  • Angiotensin II / toxicity
  • Animals
  • Antioxidants / pharmacology*
  • Antioxidants / therapeutic use
  • Aorta / cytology
  • Aorta / pathology
  • Apolipoproteins E / deficiency
  • Apolipoproteins E / genetics
  • Apoptosis / drug effects
  • Atherosclerosis / drug therapy
  • Atherosclerosis / etiology
  • Atherosclerosis / metabolism
  • Cell Survival / drug effects
  • Cells, Cultured
  • Endothelial Cells / cytology
  • Endothelial Cells / drug effects
  • Endothelial Cells / metabolism
  • Humans
  • Hydrogen Peroxide / toxicity
  • Male
  • Membrane Potential, Mitochondrial / drug effects
  • Mice
  • Mice, Knockout
  • Microscopy, Confocal
  • Mitochondria / drug effects*
  • Mitochondria / metabolism*
  • NG-Nitroarginine Methyl Ester / toxicity
  • Nitric Oxide / metabolism*
  • Nitric Oxide Synthase Type III / antagonists & inhibitors
  • Nitric Oxide Synthase Type III / metabolism
  • Oxidative Stress / drug effects
  • Oxygen Consumption / drug effects
  • Phosphorylation / drug effects
  • RNA Interference
  • RNA, Small Interfering / metabolism
  • Sirtuin 3 / antagonists & inhibitors
  • Sirtuin 3 / genetics
  • Sirtuin 3 / metabolism*
  • Umbelliferones / chemistry
  • Umbelliferones / pharmacology*
  • Umbelliferones / therapeutic use

Substances

  • Antioxidants
  • Apolipoproteins E
  • RNA, Small Interfering
  • Umbelliferones
  • Angiotensin II
  • Nitric Oxide
  • Hydrogen Peroxide
  • Nitric Oxide Synthase Type III
  • AMP-Activated Protein Kinases
  • Sirtuin 3
  • esculetin
  • NG-Nitroarginine Methyl Ester