Mulberrofuran G Protects Ischemic Injury-induced Cell Death via Inhibition of NOX4-mediated ROS Generation and ER Stress

Phytother Res. 2017 Feb;31(2):321-329. doi: 10.1002/ptr.5754. Epub 2016 Dec 2.

Abstract

The aim of this study was to investigate the neuroprotective effect of mulberrofuran G (MG) in in vitro and in vivo models of cerebral ischemia. MG was isolated from the root bark of Morus bombycis. MG inhibited nicotinamide adenine dinucleotide phosphate oxidase (NOX) enzyme activity and oxygen-glucose deprivation/reoxygenation (OGD/R)-induced NOX4 protein expression in SH-SY5Y cells. MG inhibited the expression of activated caspase-3 and caspase-9 and cleaved poly adenine dinucleotide phosphate-ribose polymerase in OGD/R-induced SH-SY5Y cells. In addition, MG protected OGD/R-induced neuronal cell death and inhibited OGD/R-induced reactive oxygen species generation in SH-SY5Y cells. In in vivo model, MG-treated groups (0.2, 1, and 5 mg/kg) reduced the infarct volume in middle cerebral artery occlusion/reperfusion-induced ischemic rats. The MG-treated groups also reduced NOX4 protein expression in middle cerebral artery occlusion/reperfusion-induced ischemic rats. Furthermore, protein expression of 78-kDa glucose-regulated protein/binding immunoglobulin protein, phosphorylated IRE1α, X-box-binding protein 1, and cytosine enhancer binding protein homologous protein, mediators of endoplasmic reticulum stress, were inhibited in MG-treated groups. Taken together, MG showed protective effect in in vitro and in vivo models of cerebral ischemia through inhibition of NOX4-mediated reactive oxygen species generation and endoplasmic reticulum stress. This finding will give an insight that inhibition of NOX enzyme activity and NOX4 protein expression could be a new potential therapeutic strategy for cerebral ischemia. Copyright © 2016 John Wiley & Sons, Ltd.

Keywords: NADPH oxidase; endoplasmic reticulum stress; middle cerebral artery occlusion/reperfusion; mulberrofuran G; neuroprotection; oxygen-glucose deprivation/reoxygenation.

MeSH terms

  • Animals
  • Benzofurans / chemistry*
  • Benzofurans / therapeutic use
  • Brain Ischemia / drug therapy*
  • Cell Death
  • Endoplasmic Reticulum Stress / drug effects*
  • Male
  • NADPH Oxidase 4
  • NADPH Oxidases / metabolism*
  • Neuroprotective Agents / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Reactive Oxygen Species
  • Signal Transduction
  • Terpenes / chemistry*
  • Terpenes / therapeutic use

Substances

  • Benzofurans
  • Neuroprotective Agents
  • Reactive Oxygen Species
  • Terpenes
  • mulberrofuran G
  • NADPH Oxidase 4
  • NADPH Oxidases
  • NOX4 protein, human