MicroRNA-107 prevents amyloid-β-induced neurotoxicity and memory impairment in mice

Int J Mol Med. 2018 Mar;41(3):1665-1672. doi: 10.3892/ijmm.2017.3339. Epub 2017 Dec 22.

Abstract

The pathogenesis of Alzheimer's disease (AD) has still not been fully elucidated, however it is thought that the build up of amyloid plaque at least partially causes the symptoms of AD. MicroRNAs (miRNAs) are endogenous non‑coding small RNA molecules that regulate the expression and degradation of proteins. The present study induced symptoms of AD in mice via intraventricular injection of amyloid‑β 1‑42 (Aβ1‑42), which decreased levels of miR‑107. However, miR‑107 levels increased following administration of miR‑107 mimic, a double‑stranded RNA molecule designed to imitate the native miRNA. Intraventricular injection of Aβ1‑42 aggregates led to spatial memory impairments, inhibited hippocampal long‑term potentiation (LTP) and resulted in the loss of pyramidal cells in the CA1 region of the hippocampus. The miR‑107 mimic reversed the impairments of spatial memory and LTP and the loss of pyramidal neurons caused by Aβ neurotoxicity. Furthermore, the miR‑107 mimic reversed the Aβ‑induced increase in Aβ1‑42 and phosphorylated Tau levels. Critically, Aβ1‑42 injection decreased levels of brain‑derived neurotrophic factor and reduced the phosphorylation of tyrosine receptor kinase B and protein kinase B; these changes were reversed following treatment with the miR‑107 mimic. Collectively, these results demonstrated that miR‑107 may be a potential target for the treatment of AD.

MeSH terms

  • Amyloid beta-Peptides / toxicity*
  • Animals
  • Brain-Derived Neurotrophic Factor / metabolism
  • Cell Death / drug effects
  • Hippocampus / metabolism
  • Hippocampus / pathology
  • Hippocampus / physiopathology
  • Long-Term Potentiation / drug effects
  • Male
  • Memory Disorders / complications
  • Memory Disorders / genetics*
  • Memory Disorders / physiopathology
  • Memory Disorders / prevention & control*
  • Mice, Inbred C57BL
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Neurotoxicity Syndromes / complications
  • Neurotoxicity Syndromes / genetics*
  • Neurotoxicity Syndromes / physiopathology
  • Neurotoxicity Syndromes / prevention & control*
  • Phosphorylation / drug effects
  • Proto-Oncogene Proteins c-akt / metabolism
  • Receptor, trkB / metabolism
  • Signal Transduction / drug effects
  • Spatial Memory / drug effects
  • Synaptic Transmission / drug effects
  • tau Proteins / metabolism

Substances

  • Amyloid beta-Peptides
  • Brain-Derived Neurotrophic Factor
  • MIRN107 microRNA, mouse
  • MicroRNAs
  • tau Proteins
  • Receptor, trkB
  • Proto-Oncogene Proteins c-akt