Z-Guggulsterone attenuates astrocytes-mediated neuroinflammation after ischemia by inhibiting toll-like receptor 4 pathway

J Neurochem. 2018 Dec;147(6):803-815. doi: 10.1111/jnc.14583. Epub 2018 Nov 12.

Abstract

Inflammatory damage plays a pivotal role in ischemic stroke pathogenesis and may represent one of the therapeutic targets. Z-Guggulsterone (Z-GS), an active component derived from myrrh, has been used to treat various diseases. The traditional uses suggest that myrrh is a good candidate for anti-inflammatory damage. This study was to investigate the anti-inflammatory and neuroprotective effects of Z-GS following cerebral ischemic injury, as well as the exact mechanisms behind them. Rat middle cerebral artery occlusion (MCAO) model and in vitro astrocytes oxygen-glucose deprivation (OGD) model were adopted to simulate ischemic stroke. Z-GS (30 or 60 mg/kg) was administered intraperitoneally immediately after reperfusion, while astrocytes were maintained in 30 or 60 μM Z-GS before OGD treatment. The results indicated that Z-GS significantly alleviated neurological deficits, infarct volume and histopathological damage in vivo, and increased the astrocytes viability in vitro. Moreover, the treatment of Z-GS inhibited the astrocytes activation and down-regulated the mRNA levels of pro-inflammatory cytokines. Furthermore, the activated TLR4-NF-κB signaling pathways induced by MCAO or OGD were significantly suppressed by Z-GS treatment, which was achieved via inhibiting the phosphorylation of JNK. Our results demonstrated that Z-GS exerted neuroprotective and anti-inflammatory properties through preventing activation of TLR4-mediated pathway in the activated astrocytes after ischemia injury. Therefore, Z-GS could be considered as a promising candidate for the treatment of ischemic stroke.

Keywords: TLR4; Z-Guggulsterone; astrocytes; ischemic stroke; neuroinflammation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Astrocytes / drug effects*
  • Brain Ischemia / complications
  • Brain Ischemia / drug therapy
  • Brain Ischemia / pathology*
  • Cytokines / biosynthesis
  • Down-Regulation
  • Glucose / deficiency
  • Hypoxia / pathology
  • Infarction, Middle Cerebral Artery / drug therapy
  • Infarction, Middle Cerebral Artery / pathology
  • Inflammation / drug therapy
  • Inflammation / etiology
  • Inflammation / pathology*
  • Male
  • Neuroprotective Agents / pharmacology
  • Neuroprotective Agents / therapeutic use*
  • Pregnenediones / pharmacology
  • Pregnenediones / therapeutic use*
  • Rats
  • Rats, Sprague-Dawley
  • Signal Transduction / drug effects
  • Toll-Like Receptor 4 / antagonists & inhibitors*
  • Treatment Outcome

Substances

  • Cytokines
  • Neuroprotective Agents
  • Pregnenediones
  • Tlr4 protein, rat
  • Toll-Like Receptor 4
  • pregna-4,17-diene-3,16-dione
  • Glucose