Ischemic pre-conditioning alters cerebral microRNAs that are upstream to neuroprotective signaling pathways

J Neurochem. 2010 Jun;113(6):1685-91. doi: 10.1111/j.1471-4159.2010.06735.x. Epub 2010 Apr 6.

Abstract

Cerebral gene expression is known to be significantly influenced by a sublethal ischemic event (pre-conditioning; PC) that induces tolerance to future damaging ischemic events. Small non-coding RNAs known as microRNAs (miRNAs) were recently shown to control the mRNA translation. We currently profiled cerebral miRNAs in the cerebral cortex of rats subjected to PC. The miRNAome reacted quickly and by 6 h following PC, levels of 51 miRNAs were altered (26 up- and 25 down-regulated; > 1.5-fold change). Twenty of these stayed at the altered level even at 3 days after PC. At least nine miRNAs showed > 5-fold change at one or more time points between 6 h to 3 days after PC compared with sham. Bioinformatics analysis showed 2007 common targets of the miRNAs that were up-regulated and 459 common targets of the miRNAs that were down-regulated after PC. Pathways analysis showed that MAP-kinase and Mammalian target of rapamycin (mTOR) signaling are the top two Kyoto Encyclopedia of Genes and Genomes pathways targeted by the up-regulated miRNAs, and Wnt and GnRH signaling are the top two Kyoto Encyclopedia of Genes and Genomes pathways targeted by the down-regulated miRNAs after PC. We hypothesize that alterations in miRNAs and their down-stream mRNAs of signaling pathways might play a role in the induction of ischemic tolerance.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cerebral Cortex / metabolism*
  • Computational Biology
  • Gene Expression Profiling / methods
  • Gene Expression Regulation / physiology*
  • Gene Regulatory Networks / physiology*
  • Ischemic Preconditioning / methods*
  • Male
  • MicroRNAs / metabolism*
  • Oligonucleotide Array Sequence Analysis / methods
  • Rats
  • Rats, Inbred SHR
  • Signal Transduction / physiology*
  • Time Factors

Substances

  • MicroRNAs