MicroRNA-328a regulates water maze performance in PTZ-kindled rats

Brain Res Bull. 2016 Jul:125:205-10. doi: 10.1016/j.brainresbull.2016.07.008. Epub 2016 Jul 19.

Abstract

The down-regulation of microRNA-328a (miR-328a) in pentylenetetrazole (PTZ)-kindled rats with memory impairment was demonstrated in our previous study, while any contribution of miR-328a to cognitive dysfunction of PTZ-kindled rats remains unknown. In this study we have investigated the effect and the underlying mechanism of miR-328a on the cognitive function in PTZ-kindled rats. 48 SD male rats were divided into 4 groups as follows: a PTZ kindled group, a miR-328a antagomir group, an antagomir-control group, and a sham group (n=12 for each). All rats except those from the sham group were treated with PTZ 14 times at intervals of 48h to establish the temporal lobe epilepsy (TLE) models, and miR-328a antagomir was given to the antagomir group as a treatment by lateral-ventricle injection the day after the first injection of PTZ. Morris water maze (MWM) test was performed to assay their learning and memory abilities. The down-regulation of miR-328a in the PTZ group was confirmed using RT-qPCR and the expression of miR-328a was diminished after antagomir treatment (P<0.05). In the probe test of water maze, the time and distance of the PTZ group were both shorter than those of the sham group (P<0.05), and those of the antagomir-control group were both longer than those of the antagomir group (P<0.05). In addition, we found that with the down-regulation of miR-328a, the levels of Beta-site APP-cleaving enzyme (BACE), which is a bioinformatics-predicted target of miR-328a, were up-regulated. These findings suggest that miR-328a may play a role in memory dysfunction in PTZ-kindled rats by regulating the BACE levels and this links the PTZ model with Alzheimer's disease.

Keywords: Alzheimer's disease; BACE; Cognitive function; Epilepsy; microRNA-328a.

MeSH terms

  • Amyloid Precursor Protein Secretases / metabolism
  • Animals
  • Antagomirs / pharmacology
  • Aspartic Acid Endopeptidases / metabolism
  • Disease Models, Animal
  • Down-Regulation / drug effects*
  • Epilepsy, Temporal Lobe / chemically induced*
  • GTP-Binding Proteins / metabolism
  • GTPase-Activating Proteins / metabolism
  • Kindling, Neurologic / drug effects*
  • Kindling, Neurologic / physiology
  • Male
  • Maze Learning / drug effects*
  • Maze Learning / physiology
  • MicroRNAs / chemistry
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Neoplasm Proteins / metabolism
  • Pentylenetetrazole / toxicity*
  • Rats
  • Rats, Sprague-Dawley

Substances

  • Antagomirs
  • Bcl9l protein, rat
  • GTPase-Activating Proteins
  • MicroRNAs
  • Neoplasm Proteins
  • Syngap1 protein, rat
  • Amyloid Precursor Protein Secretases
  • Aspartic Acid Endopeptidases
  • Bace1 protein, rat
  • GTP-Binding Proteins
  • Pentylenetetrazole