Downregulation of MicroRNA-34c-5p facilitated neuroinflammation in drug-resistant epilepsy

Brain Res. 2020 Dec 15:1749:147130. doi: 10.1016/j.brainres.2020.147130. Epub 2020 Sep 17.

Abstract

Drug-resistant epilepsy patients has aberrant inflammatory mediator levels. However, the mechanism of which is remains unillustrated. Here the molecular mechanism underlying the neuroinflammatory process in patients with drug-resistant epilepsy were investigated. Bioinformatics analysis revealed that miR-34c-5p was significantly downregulated in patients with drug-resistant epilepsy, compared to control population. Then, luciferase reporter assays indicated that HMGB1, inflammation-related mediators, was the target gene of miR-34c-5p. The kainic acid-induced epileptic rats were established and divided into drug-sensitive epilepsy and drug-resistant epilepsy according to their seizure behavior and EEG after antiepileptic drug administration. Downregulation of miR-34c-5p, elevated expression of HMGB1 and IL-1β had been found in rats with drug-resistant epilepsy, compared to drug-sensitive epilepsy rats. Aggravated hippocampal neuron loss was demonstrated in rats with drug-resistant epilepsy. The results from epileptic rats were subsequently validated from children with drug-resistant epilepsy. Analysis manifested that miR-34c-5p was obviously decreased, while HMGB1 was increased on serum of children with drug-resistant epilepsy. Our study highlights that decreased miR-34c-5p in drug-resistant epilepsy exacerbates neuroinflammation, which aggravates hippocampal neuron loss in epileptogenesis. Thus, miR-34c-5p could be considered as a potential noninvasive biomarker and shed novel light on the development of an effective therapeutic strategy for children with drug-resistant epilepsy in the future.

Keywords: Drug-resistant epilepsy; HMGB1; Neuron loss; Pediatric; miR-34c-5p.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Animals
  • Child
  • Child, Preschool
  • Down-Regulation*
  • Drug Resistant Epilepsy / genetics
  • Drug Resistant Epilepsy / metabolism*
  • Epilepsy, Temporal Lobe / genetics
  • Epilepsy, Temporal Lobe / metabolism*
  • Female
  • HMGB1 Protein / genetics
  • HMGB1 Protein / metabolism*
  • Hippocampus / metabolism
  • Humans
  • Inflammation / genetics
  • Inflammation / metabolism*
  • Interleukin-1beta / genetics
  • Interleukin-1beta / metabolism*
  • Male
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Neurons / metabolism
  • Rats
  • Rats, Sprague-Dawley

Substances

  • HMGB1 Protein
  • Interleukin-1beta
  • MIRN34 microRNA, human
  • MicroRNAs