title: PERK inhibition prevents tau-mediated neurodegeneration in a mouse model of frontotemporal dementia.
abstract: The PERK-eIF2α branch of the Unfolded Protein Response (UPR) mediates the transient shutdown of translation in response to rising levels of misfolded proteins in the endoplasmic reticulum. PERK and eIF2α activation are increasingly recognised in postmortem analyses of patients with neurodegenerative disorders, including Alzheimer's disease, the tauopathies and prion disorders. These are all characterised by the accumulation of misfolded disease-specific proteins in the brain in association with specific patterns of neuronal loss, but the role of UPR activation in their pathogenesis is unclear. In prion-diseased mice, overactivation of PERK-P/eIF2α-P signalling results in the sustained reduction in global protein synthesis, leading to synaptic failure, neuronal loss and clinical disease. Critically, restoring vital neuronal protein synthesis rates by inhibiting the PERK-eIF2α pathway, both genetically and pharmacologically, prevents prion neurodegeneration downstream of misfolded prion protein accumulation. Here we show that PERK-eIF2α-mediated translational failure is a key process leading to neuronal loss in a mouse model of frontotemporal dementia, where the misfolded protein is a form of mutant tau. rTg4510 mice, which overexpress the P301L tau mutation, show dysregulated PERK signalling and sustained repression of protein synthesis by 6 months of age, associated with onset of neurodegeneration. Treatment with the PERK inhibitor, GSK2606414, from this time point in mutant tau-expressing mice restores protein synthesis rates, protecting against further neuronal loss, reducing brain atrophy and abrogating the appearance of clinical signs. Further, we show that PERK-eIF2α activation also contributes to the pathological phosphorylation of tau in rTg4510 mice, and that levels of phospho-tau are lowered by PERK inhibitor treatment, providing a second mechanism of protection. The data support UPR-mediated translational failure as a generic pathogenic mechanism in protein-misfolding disorders, including tauopathies, that can be successfully targeted for prevention of neurodegeneration.
authors.affiliation: MRC Toxicology Unit, Hodgkin Building, University of Leicester, Lancaster Road, Leicester, LE1 9HN, UK.
authors.forename: Helois
authors.initials: H
authors.lastname: Radford
authors.affiliation: MRC Toxicology Unit, Hodgkin Building, University of Leicester, Lancaster Road, Leicester, LE1 9HN, UK.|Department of Microbiology, Immunology and Pathology, Prion Research Center, Colorado State University, Fort Collins, CO, 80523-1619, USA.
authors.forename: Julie A
authors.initials: JA
authors.lastname: Moreno
authors.affiliation: MRC Toxicology Unit, Hodgkin Building, University of Leicester, Lancaster Road, Leicester, LE1 9HN, UK.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Verity
authors.affiliation: MRC Toxicology Unit, Hodgkin Building, University of Leicester, Lancaster Road, Leicester, LE1 9HN, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Halliday
authors.affiliation: MRC Toxicology Unit, Hodgkin Building, University of Leicester, Lancaster Road, Leicester, LE1 9HN, UK. gm522@cam.ac.uk.|Department of Clinical Neurosciences, University of Cambridge, Cambridge, CB2 0AH, UK. gm522@cam.ac.uk.
authors.forename: Giovanna R
authors.initials: GR
authors.lastname: Mallucci
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000818:Animals; D001284:Atrophy; D001921:Brain / Q000187:drug effects / Q000201:enzymology / Q000473:pathology; D004195:Disease Models, Animal; D005260:Female; D057180:Frontotemporal Dementia / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D008297:Male; D008822:Mice, Transgenic; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology; D009154:Mutation; D009474:Neurons / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D018696:Neuroprotective Agents / Q000494:pharmacology*; D009929:Organ Size; D010766:Phosphorylation / Q000187:drug effects; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D019892:eIF-2 Kinase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D016875:tau Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D000225:Adenine; D007211:Indoles; D018696:Neuroprotective Agents; D047428:Protein Kinase Inhibitors; D019892:eIF-2 Kinase; D016875:tau Proteins; C576403:7-methyl-5-(1-((3-(trifluoromethyl)phenyl)acetyl)-2,3-dihydro-1H-indol-5-yl)-7H-pyrrolo(2,3-d)pyrimidin-4-amine; C054369:MAPT protein, human
keywords: Dementia; Neurodegeneration; PERK; Tau; Unfolded Protein Response