Antagomirs Targeting MicroRNA-134 Increase Limk1 Levels After Experimental Seizures in Vitro and in Vivo

Cell Physiol Biochem. 2017;43(2):636-643. doi: 10.1159/000480647. Epub 2017 Sep 22.

Abstract

Background: MiR-134 is enriched in dendrites of hippocampal neurons and plays crucial roles in the progress of epilepsy. The present study aims to investigate the effects of antagomirs targeting miroRNA-134 (Ant-134) on limk1 expression and the binding of miR-134 and limk1 in experimental seizure.

Methods: Status epilepticus (SE) rat model was established by lithium chloride-pilocarpine injection and was treated with Ant-134 by intracerebroventricular injection. Low Mg2+-exposed primary neurons were used as an in vitro model of SE. The expression of miR-134 was determined using real-time PCR. Protein expressions of limk1 and cofilin were determined by Western blotting. Luciferase reporter assay was used to examine the binding between miR-134 and limk1 3'-untranslated region.

Results: The expression of miR-134 was markedly enhanced in hippocampus of the SE rats and low Mg2+-exposed neurons. Ant-134 increased the expression of limk1 and reduced the expression of cofilin in the SE hippocampus and Low Mg2+-exposed neurons. In addition, luciferase reporter assay confirmed that miR-134 bound limk1 3'-UTR. MiR-134 overexpression inhibited limk1 mRNA and protein expressions in neurons.

Conclusion: Blockage of miR-134 upregulates limk1 expression and downregulated cofilin expression in hippocampus of the SE rats. This mechanism may contribute to the neuroprotective effects of Ant-134.

Keywords: Cofilin; Epilepsy; Hippocampus; Limk1; MiR-134.

MeSH terms

  • Animals
  • Antagomirs / therapeutic use*
  • Cells, Cultured
  • Genetic Therapy
  • Hippocampus / metabolism
  • Hippocampus / pathology
  • Lim Kinases / genetics*
  • Male
  • MicroRNAs / genetics*
  • Neurons / metabolism
  • Neurons / pathology
  • Rats, Sprague-Dawley
  • Seizures / genetics
  • Seizures / pathology
  • Seizures / therapy*
  • Status Epilepticus / genetics
  • Status Epilepticus / pathology
  • Status Epilepticus / therapy*
  • Up-Regulation*

Substances

  • Antagomirs
  • MIRN134 microRNA, rat
  • MicroRNAs
  • Lim Kinases
  • Limk1 protein, rat