Cerebral ischemia induces the aggregation of proteins linked to neurodegenerative diseases

Sci Rep. 2018 Feb 9;8(1):2701. doi: 10.1038/s41598-018-21063-z.

Abstract

Protein aggregation critically affects cell viability in neurodegenerative diseases, but whether this also occurs in ischemic brain injury remains elusive. Prior studies report the post-ischemic aggregation of ubiquitin, small ubiquitin-related modifier (SUMO) and ribosomes, however whether other proteins are also affected is unknown. Here we employed a proteomic approach to identify the insoluble, aggregated proteome after cerebral ischemia. Mice underwent transient middle cerebral artery occlusion or sham-surgery. After 1-hour reperfusion, prior to apparent brain injury, mice were sacrificed and detergent-insoluble proteins were obtained and identified by nanoLC-MS/MS. Naturally existing insoluble proteins were determined in sham controls and aggregated proteins after cerebral ischemia/reperfusion were identified. Selected aggregated proteins found by proteomics were biochemically verified and aggregation propensities were studied during ischemia with or without reperfusion. We found that ischemia/reperfusion induces the aggregation of RNA-binding and heat-shock proteins, ubiquitin, SUMO and other proteins involved in cell signalling. RNA-binding proteins constitute the largest group of aggregating proteins in ischemia. These include TDP43, FUS, hnRNPA1, PSF/SFPQ and p54/NONO, all of which have been linked to neurodegeneration associated with amyotrophic lateral sclerosis and frontotemporal dementia. The aggregation of neurodegeneration-related disease proteins in cerebral ischemia unveils a previously unappreciated molecular overlap between neurodegenerative diseases and ischemic stroke.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain Ischemia / metabolism*
  • Brain Ischemia / physiopathology*
  • Cerebral Infarction
  • Cerebrovascular Circulation / physiology
  • Hippocampus / metabolism
  • Infarction, Middle Cerebral Artery / metabolism
  • Infarction, Middle Cerebral Artery / physiopathology
  • Ischemic Attack, Transient
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Middle Cerebral Artery / physiopathology
  • Neurodegenerative Diseases / metabolism
  • Neurons / metabolism
  • Protein Aggregates / physiology
  • Proteomics / methods
  • Reperfusion
  • Reperfusion Injury / metabolism
  • Small Ubiquitin-Related Modifier Proteins / metabolism
  • Stroke / metabolism
  • Tandem Mass Spectrometry
  • Ubiquitin / metabolism

Substances

  • Protein Aggregates
  • Small Ubiquitin-Related Modifier Proteins
  • Ubiquitin