Alterations in miRNA levels in the dentate gyrus in epileptic rats

PLoS One. 2013 Oct 11;8(10):e76051. doi: 10.1371/journal.pone.0076051. eCollection 2013.

Abstract

The aim of this study was to characterize changes in miRNA expression in the epileptic dentate gyrus. Status epilepticus evoked by amygdala stimulation was used to induce epilepsy in rats. The dentate gyri were isolated at 7 d, 14 d, 30 d and 90 d after stimulation (n=5). Sham-operated time-matched controls were prepared for each time point (n=5). The miRNA expression was evaluated using Exiqon microarrays. Additionally, mRNA from the same animals was profiled using Affymetrix microarrays. We detected miRNA expression signatures that differentiate between control and epileptic animals. Significant changes in miRNA expression between stimulated and sham operated animals were observed at 7 and 30 d following stimulation. Moreover, we found that there are ensembles of miRNAs that change expression levels over time. Analysis of the mRNA expression from the same animals revealed that the expression of several mRNAs that are potential targets for miRNA with altered expression level is regulated in the expected direction. The functional characterization of miRNAs and their potential mRNA targets indicate that miRNA can participate in several molecular events that occur in epileptic tissue, including immune response and neuronal plasticity. This is the first report on changes in the expression of miRNA and the potential functional impact of these changes in the dentate gyrus of epileptic animals. Complex changes in the expression of miRNAs suggest an important role for miRNA in the molecular mechanisms of epilepsy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amygdala / physiopathology
  • Animals
  • Dentate Gyrus / metabolism*
  • Dentate Gyrus / physiopathology
  • Electric Stimulation
  • Immunity, Innate / genetics
  • Male
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • Neuronal Plasticity / genetics
  • Oligonucleotide Array Sequence Analysis
  • RNA, Messenger / genetics*
  • RNA, Messenger / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Status Epilepticus / metabolism*
  • Status Epilepticus / physiopathology
  • Transcriptome*

Substances

  • MicroRNAs
  • RNA, Messenger

Grants and funding

This work was supported by National Research Centre grant 2011/01/M/NZ3/02139 and Ministry of Science and Education grant DNP/N119/ESF-EuroEPINOMICS/2012. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.