Downregulation of TRB3 protects neurons against apoptosis induced by global cerebral ischemia and reperfusion injury in rats

Neuroscience. 2017 Sep 30:360:118-127. doi: 10.1016/j.neuroscience.2017.07.062. Epub 2017 Aug 4.

Abstract

Global cerebral ischemia and reperfusion injury (GCI/R) can lead to neuronal apoptosis and contributes to permanent neurological sequelae. However, the underlying mechanism is largely unknown. Therefore, the present study aimed to assess the effects of GCI/R on the tribbles homolog 3 (TRB3) and to explore the role of TRB3 in GCI/R. The GCI/R model was developed in Sprague-Dawley male rats by four-vessel occlusion. Subsequently, the expressions of TRB3, endoplasmic reticulum stress markers, and apoptosis-associated proteins were examined by western blot at 1h, 6h, 12h, 24h, and 72h after GCI/R. TRB3 short-hairpin RNA (shRNA) lentivirus was constructed and used to investigate the role of TRB3 in GCI/R-induced neuronal apoptosis. GCI/R increased the level of TRB3, endoplasmic reticulum stress markers, and pro-apoptotic proteins. The level of protein kinase B (Akt) phosphorylation was reduced during GCI/R. Administration of TRB3 shRNA lentivirus attenuated GCI/R-induced up-regulation of TRB3, endoplasmic reticulum stress, and neuronal apoptosis. Furthermore, TRB3 shRNA lentivirus reversed the reduced level of Akt phosphorylation induced by GCI/R. These data implied that TRB3 participated in the GCI/R-induced neuronal apoptosis. Knocking down TRB3 attenuated endoplasmic reticulum stress, enhanced Akt phosphorylation, and protected neurons from apoptosis in response to GCI/R. These results demonstrated that the downregulation of TRB3 may be a promising approach for treating GCI/R.

Keywords: apoptosis; cerebral ischemia; endoplasmic reticulum stress; homolog tribbles 3; neuron.

MeSH terms

  • Animals
  • Apoptosis / physiology*
  • Brain Ischemia / metabolism*
  • Brain Ischemia / physiopathology
  • Down-Regulation / drug effects
  • Endoplasmic Reticulum Stress / physiology
  • Male
  • Neurons / metabolism
  • Neuroprotective Agents / pharmacology
  • Phosphorylation
  • Protein Serine-Threonine Kinases / antagonists & inhibitors*
  • Protein Serine-Threonine Kinases / metabolism
  • Rats, Sprague-Dawley
  • Reperfusion Injury / metabolism*

Substances

  • Neuroprotective Agents
  • Trib3 protein, rat
  • Protein Serine-Threonine Kinases