MicroRNA-495 Inhibits New Bone Regeneration via Targeting High Mobility Group AT-Hook 2 (HMGA2)

Med Sci Monit. 2017 Sep 30:23:4689-4698. doi: 10.12659/msm.904404.

Abstract

BACKGROUND MicroRNAs play critical roles in post-translational gene expression. In this study, we explored the role of miR-495 in new bone regeneration. MATERIAL AND METHODS Murine calvarial osteoblasts were isolated and cultured. Microarray was performed to identify differential miRNAs in medicarpin-induced osteoblasts differentiation. Luciferase reporter assay was performed to identify the target gene of miRNA. Murine osteoblast cells were transfected with miC, miR-495, or anti-miR-495. CCK-8 and flow cytometry were performed to detect osteoblasts proliferation and apoptosis. Western blot was used to analyze apoptosis-related proteins. qRT-PCR analysis was performed to detect gene expression. ALP activity and mineralized nodule formation test were used to evaluate bone formation. Dill-hole injury model was constructed and micro CT was utilized to measuring bone healing. RESULTS Microarray analysis identified miR-495 as our miRNA of interest and luciferase reporter assay identified HMGA2 as its target gene. Over-expression of miR-495 significantly inhibited ALP activity and mineralized nodule formation as well as the expression of RUNX-2, BMP-2, and Osterix. Also, miR-495 over-expression inhibited osteoblasts proliferation and promoted apoptosis obviously. In this in vivo study, the downregulation of miR-495 promoted murine femur healing. CONCLUSIONS MiR-495 inhibits new bone regeneration via targeting high mobility group AT-Hook 2 (HMGA2). We propose that targeting miR-495 may be a promising therapeutic approach for bone regeneration.

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Apoptosis / genetics
  • Bone Regeneration / drug effects
  • Bone Regeneration / genetics*
  • Cell Differentiation / drug effects
  • Cell Differentiation / genetics
  • Cell Proliferation / drug effects
  • Femur / diagnostic imaging
  • Femur / drug effects
  • Femur / pathology
  • HMGA2 Protein / metabolism*
  • Mice
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Osteoblasts / cytology
  • Osteoblasts / drug effects
  • Osteoblasts / metabolism
  • Osteogenesis / drug effects
  • Osteogenesis / genetics
  • Pterocarpans / pharmacology
  • X-Ray Microtomography

Substances

  • HMGA2 Protein
  • MIRN495 microRNA, mouse
  • MicroRNAs
  • Pterocarpans
  • medicarpin