EF1A1/HSC70 Cooperatively Suppress Brain Endothelial Cell Apoptosis via Regulating JNK Activity

CNS Neurosci Ther. 2016 Oct;22(10):836-44. doi: 10.1111/cns.12581. Epub 2016 Jun 20.

Abstract

Aims: In our previous study, eEF1A1 was identified to be a new target for protecting brain ischemia injury, but the mechanism remains largely unknown. In this study, we screened the downstream cellular protein molecules interacted with eEF1A1 and found mechanism of eEF1A1 in brain ischemia protection.

Methods and results: Through co-immunoprecipitation and mass spectrometry for searching the interaction of proteins with eEF1A1 in bEnd3 cells, HSC70 was identified to be a binding protein of eEF1A1, which was further validated by Western blot and immunofluorescence. eEF1A1 or HSC70 knockdown, respectively, increased OGD-induced apoptosis of brain vascular endothelial cells, which was detected by Annexin V-FITC/PI staining. HSC70 or eEF1A1 knockdown enhances phosphorylated JNK, phosphorylation of c-JUN (Ser63, Ser73), cleaved caspase-9, and cleaved caspase-3 expression, which could be rescued by JNK inhibitor.

Conclusion: In summary, our data suggest that the presence of chaperone forms of interaction between eEF1A1 and HSC70 in brain vascular endothelial cells, eEF1A1 and HSC70 can play a protective role in the process of ischemic stroke by inhibiting the JNK signaling pathway activation.

Keywords: Apoptosis; Cerebral ischemia; Eukaryotic elongation factor 1A1 (eEF1A1); Heat shock cognate protein 70 (HSC70).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Animals
  • Annexin A5 / metabolism
  • Apoptosis / drug effects
  • Brain / cytology
  • Cells, Cultured
  • Endothelial Cells / drug effects
  • Endothelial Cells / metabolism*
  • Enzyme Inhibitors / pharmacology
  • Flow Cytometry
  • HSC70 Heat-Shock Proteins / genetics
  • HSC70 Heat-Shock Proteins / metabolism*
  • Immunoprecipitation
  • MAP Kinase Kinase 4 / metabolism*
  • MAP Kinase Signaling System / drug effects
  • MAP Kinase Signaling System / physiology
  • Mass Spectrometry
  • Mice
  • Microscopy, Confocal
  • Peptide Elongation Factor 1 / genetics
  • Peptide Elongation Factor 1 / metabolism*
  • RNA, Small Interfering / pharmacology
  • Time Factors

Substances

  • Annexin A5
  • Enzyme Inhibitors
  • HSC70 Heat-Shock Proteins
  • Hspa8 protein, mouse
  • Peptide Elongation Factor 1
  • RNA, Small Interfering
  • eEF1A-1 protein, mouse
  • MAP Kinase Kinase 4