miR-129 controls axonal regeneration via regulating insulin-like growth factor-1 in peripheral nerve injury

Cell Death Dis. 2018 Jun 18;9(7):720. doi: 10.1038/s41419-018-0760-1.

Abstract

The microenvironment of peripheral nerve regeneration consists of multiple neurotrophic factors, adhesion molecules, and extracellular matrix molecules, secreted by unique glial cells in the peripheral nerve system (PNS)-Schwann cell (SCs). Following peripheral nerve injury (PNI), local IGF-1 production is upregulated in SCs and denervated muscle during axonal sprouting and regeneration. Regulation of IGF-1/IGF-1R signaling is considered as a potentially targeted therapy of PNI. We previously identified a group of novel miRNAs in proximal nerve following rat sciatic nerve transection. The present work focused on the role of miR-129 in regulation of IGF-1 signaling after sciatic nerve injury. The temporal change profile of the miR-129 expression was negatively correlated with the IGF-1 expression in proximal nerve stump and dorsal root ganglion (DRG) following sciatic nerve transection. An increased expression of miR-129 inhibited proliferation and migration of SCs, and axonal outgrowth of DRG neurons, which was inversely promoted by silencing of the miR-129 expression. The IGF-1 was identified as one of the multiple target genes of miR-129, which exerted negative regulation of IGF-1 by translational suppression. Moreover, knockdown of IGF-1 attenuated the promoting effects of miR-129 inhibitor on proliferation and migration of SCs, and neurite outgrowth of DRG neurons. Overall, our data indicated that miR-129 own the potential to regulate the proliferation and migration of SCs by targeting IGF-1, providing further insight into the regulatory role of miRNAs in peripheral nerve regeneration. The present work not only provides new insight into miR-129 regulation of peripheral nerve regeneration by robust phenotypic modulation of neural cells, but also opens a novel therapeutic window for PNI by mediating IGF-1 production. Our results may provide further experimental basis for translation of the molecular therapy into the clinic.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Axons / physiology*
  • Cells, Cultured
  • Gene Expression Regulation
  • HEK293 Cells
  • Humans
  • Insulin-Like Growth Factor I / genetics*
  • Insulin-Like Growth Factor I / metabolism
  • Male
  • MicroRNAs / physiology*
  • Nerve Regeneration / genetics*
  • Peripheral Nerve Injuries / genetics*
  • Peripheral Nerve Injuries / pathology
  • Rats
  • Rats, Sprague-Dawley

Substances

  • MIRN129 microRNA, rat
  • MicroRNAs
  • Insulin-Like Growth Factor I