Age-dependent impaired neurogenic differentiation capacity of dental stem cell is associated with Wnt/β-catenin signaling

Cell Mol Neurobiol. 2013 Nov;33(8):1023-31. doi: 10.1007/s10571-013-9965-0. Epub 2013 Sep 17.

Abstract

Two kinds of dental stem cells (DSCs), dental pulp stem cells (DPSCs) and stem cells from human-exfoliated deciduous teeth (SHED), have been identified as novel populations of mesenchymal stem cells that can be induced to differentiate into osteoblasts, chondrocytes, adipocytes, and neuron-like cells in vitro. As we know, both of them originate from the neural crest, but have distinct characteristics and functions in vitro and in vivo. The regeneration potential of DSCs declines with advanced age; however, the mechanism of the impaired potential in DSCs has not been fully explored. In this study, we investigated whether declined neurogenic differentiation capacity is associated with an altered expression of Wnt signaling-related proteins in vitro. We compared stem cells isolated from human dental pulp in two age groups: the exfoliated deciduous teeth (5-12 years), and the third permanent teeth (45-50 years). We found that the expression levels of neuron markers, such as βIII-tubulin, microtubule-associated protein 2(MAP2), tyrosine hydroxylase (TH), and Nestin were lower in the DPSCs group compared with that in the SHED group; however, in supplementation with human recombinant Wnt1 in the medium, the DPSCs were prone to neural differentiation and expressed higher levels of neurogenic markers. In summary, our study demonstrated that Wnt/β-catenin signaling may play a vital role in the age-dependent neural differentiation of DSCs. Therefore, DSCs may provide an ideal source of stem cells that can further extend their therapeutic application in nerve injury and neurodegenerative diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aging / metabolism*
  • Cell Differentiation*
  • Cell Nucleus / metabolism
  • Cell Shape
  • Child
  • Child, Preschool
  • Dental Pulp / cytology
  • Female
  • Humans
  • Immunophenotyping
  • Male
  • Middle Aged
  • Neurogenesis*
  • Neurons / cytology*
  • Stem Cells / cytology*
  • Stem Cells / metabolism*
  • Tooth Exfoliation / pathology
  • Tooth, Deciduous / cytology
  • Wnt Signaling Pathway*
  • Wnt1 Protein / metabolism

Substances

  • WNT1 protein, human
  • Wnt1 Protein