Oral treatment targeting the unfolded protein response prevents neurodegeneration and clinical disease in prion-infected mice

Sci Transl Med. 2013 Oct 9;5(206):206ra138. doi: 10.1126/scitranslmed.3006767.

Abstract

During prion disease, an increase in misfolded prion protein (PrP) generated by prion replication leads to sustained overactivation of the branch of the unfolded protein response (UPR) that controls the initiation of protein synthesis. This results in persistent repression of translation, resulting in the loss of critical proteins that leads to synaptic failure and neuronal death. We have previously reported that localized genetic manipulation of this pathway rescues shutdown of translation and prevents neurodegeneration in a mouse model of prion disease, suggesting that pharmacological inhibition of this pathway might be of therapeutic benefit. We show that oral treatment with a specific inhibitor of the kinase PERK (protein kinase RNA-like endoplasmic reticulum kinase), a key mediator of this UPR pathway, prevented UPR-mediated translational repression and abrogated development of clinical prion disease in mice, with neuroprotection observed throughout the mouse brain. This was the case for animals treated both at the preclinical stage and also later in disease when behavioral signs had emerged. Critically, the compound acts downstream and independently of the primary pathogenic process of prion replication and is effective despite continuing accumulation of misfolded PrP. These data suggest that PERK, and other members of this pathway, may be new therapeutic targets for developing drugs against prion disease or other neurodegenerative diseases where the UPR has been implicated.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenine / administration & dosage
  • Adenine / analogs & derivatives*
  • Adenine / blood
  • Adenine / pharmacology
  • Adenine / therapeutic use
  • Administration, Oral
  • Animals
  • Blood-Brain Barrier / drug effects
  • Blood-Brain Barrier / pathology
  • Brain / drug effects
  • Brain / enzymology
  • Eukaryotic Initiation Factor-2 / metabolism
  • Indoles / administration & dosage*
  • Indoles / blood
  • Indoles / pharmacology*
  • Indoles / therapeutic use
  • Mice
  • Nerve Degeneration / drug therapy*
  • Nerve Degeneration / enzymology
  • Nerve Degeneration / pathology
  • Nerve Degeneration / prevention & control*
  • Neuroprotective Agents / pharmacology
  • Neuroprotective Agents / therapeutic use
  • Phosphorylation / drug effects
  • Prion Diseases / drug therapy*
  • Prion Diseases / enzymology
  • Prion Diseases / pathology
  • Prion Diseases / prevention & control*
  • Prions
  • Protein Biosynthesis / drug effects
  • Synapses / drug effects
  • Synapses / metabolism
  • Unfolded Protein Response / drug effects*
  • eIF-2 Kinase / antagonists & inhibitors
  • eIF-2 Kinase / metabolism

Substances

  • 7-methyl-5-(1-((3-(trifluoromethyl)phenyl)acetyl)-2,3-dihydro-1H-indol-5-yl)-7H-pyrrolo(2,3-d)pyrimidin-4-amine
  • Eukaryotic Initiation Factor-2
  • Indoles
  • Neuroprotective Agents
  • Prions
  • PERK kinase
  • eIF-2 Kinase
  • Adenine