Erythropoietin modulates autophagy signaling in the developing rat brain in an in vivo model of oxygen-toxicity

Int J Mol Sci. 2012 Oct 10;13(10):12939-51. doi: 10.3390/ijms131012939.

Abstract

Autophagy is a self-degradative process that involves turnover and recycling of cytoplasmic components in healthy and diseased tissue. Autophagy has been shown to be protective at the early stages of programmed cell death but it can also promote apoptosis under certain conditions. Earlier we demonstrated that oxygen contributes to the pathogenesis of neonatal brain damage, which can be ameliorated by intervention with recombinant human erythropoietin (rhEpo). Extrinsic- and intrinsic apoptotic pathways are involved in oxygen induced neurotoxicity but the role of autophagy in this model is unclear. We analyzed the expression of autophagy activity markers in the immature rodent brain after exposure to elevated oxygen concentrations. We observed a hyperoxia-exposure dependent regulation of autophagy-related gene (Atg) proteins Atg3, 5, 12, Beclin-1, microtubule-associated protein 1 light chain 3 (LC3), LC3A-II, and LC3B-II which are all key autophagy activity proteins. Interestingly, a single injection with rhEpo at the onset of hyperoxia counteracted these oxygen-mediated effects. Our results indicate that rhEpo generates its protective effect by modifying the key autophagy activity proteins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis Regulatory Proteins / genetics
  • Apoptosis Regulatory Proteins / metabolism
  • Autophagy / drug effects*
  • Autophagy-Related Protein 5
  • Autophagy-Related Proteins
  • Beclin-1
  • Brain / drug effects
  • Brain / metabolism*
  • Epoetin Alfa
  • Erythropoietin / pharmacology*
  • Humans
  • Hypoxia*
  • Microtubule-Associated Proteins / metabolism
  • Models, Animal
  • Peptide Synthases / genetics
  • Peptide Synthases / metabolism
  • Proteins / genetics
  • Proteins / metabolism
  • Rats
  • Rats, Wistar
  • Recombinant Proteins / pharmacology
  • Signal Transduction / drug effects

Substances

  • Apoptosis Regulatory Proteins
  • Atg5 protein, rat
  • Autophagy-Related Protein 5
  • Autophagy-Related Proteins
  • Beclin-1
  • Becn1 protein, rat
  • LC3 protein, rat
  • Microtubule-Associated Proteins
  • Proteins
  • Recombinant Proteins
  • Erythropoietin
  • Epoetin Alfa
  • Atg3 protein, rat
  • Peptide Synthases