MicroRNA-124-loaded nanoparticles increase survival and neuronal differentiation of neural stem cells in vitro but do not contribute to stroke outcome in vivo

PLoS One. 2018 Mar 1;13(3):e0193609. doi: 10.1371/journal.pone.0193609. eCollection 2018.

Abstract

There is a high quest for novel therapeutic strategies to enhance recovery after stroke. MicroRNA-124 (miR-124) has been described as neuroprotective and anti-inflammatory molecule. Moreover, miR-124 is a well described enhancer of adult neurogenesis that could offer potentially beneficial effects. Herein, we used miR-124-loaded nanoparticles (miR-124 NPs) to evaluate their therapeutic potential in an in vitro and in vivo model of stroke. For that, neuroprotective and neurogenic responses were assessed in an in vitro model of stroke. Here, we found that miR-124 NPs decreased cell death and improved neuronal differentiation of subventricular zone (SVZ) neural stem cell cultures after oxygen and glucose deprivation. In contrast, intravenous injection of miR-124 NPs immediately after permanent focal ischemia induced by photothrombosis (PT) did not provide a better neurological outcome. In addition, treatment did not affect the number of 5-bromo-2'-deoxyuridine (BrdU)- and doublecortin/BrdU- positive cells in the SVZ at the study endpoint of 14 days after PT. Likewise, the ischemic insult did not affect the numbers of neuronal progenitors in the SVZ. However, in PT mice miR-124 NPs were able to specifically augment interleukin-6 levels at day 2 post-stroke. Furthermore, we also showed that NPs reached the brain parenchyma and were internalized by brain resident cells. Although, promising in vitro data could not be verified in vivo as miR-124 NPs treatment did not improve functional outcome nor presented beneficial actions on neurogenesis or post-stroke inflammation, we showed that our NP formulation can be a safe alternative for drug delivery into the brain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Intravenous
  • Animals
  • Apoptosis / drug effects
  • Brain Ischemia / etiology
  • Brain Ischemia / genetics
  • Brain Ischemia / immunology*
  • Cell Differentiation / drug effects
  • Cell Proliferation
  • Cells, Cultured
  • Disease Models, Animal
  • Interleukin-6 / blood
  • Interleukin-6 / metabolism*
  • Male
  • Mice
  • MicroRNAs / administration & dosage*
  • MicroRNAs / genetics
  • MicroRNAs / pharmacology
  • Nanoparticles / administration & dosage
  • Nanoparticles / chemistry
  • Neural Stem Cells / cytology*
  • Neural Stem Cells / drug effects
  • Stroke / etiology
  • Stroke / genetics
  • Stroke / immunology*
  • Treatment Outcome

Substances

  • Interleukin-6
  • MIRN124 microRNA, human
  • MicroRNAs
  • interleukin-6, mouse

Grants and funding

This work was supported by FEDER funds through the POCI - COMPETE 2020 - Operational Programme Competitiveness and Internationalisation in Axis I - Strengthening research, technological development and innovation (Project POCI-01-0145-FEDER-007491; Project 3386 - “StrokeTherapy”) and National Funds by FCT - Foundation for Science and Technology (grant SFRH/BD/90365/2012 and Project UID/Multi /00709/2013) to LB, the Swedish Brain Fund, the Crafoord Foundation to KR, the Swedish Research Council, Sveriges Stroke Riksförbundet to KR, the Hans-Christian and Alice Wachtmeister Foundation and the Stiftelsen Sven-Olof Jansons livsverk to KR.