TGF- beta 3 induces ectopic mineralization in fetal mouse dental pulp during tooth germ development

• Published in: Development, growth & differentiation Vol. 47; no. 3; pp. 141 - 152
• Main Authors: Huojia, Muhetaer, Muraoka, Noriko, Yoshizaki, Keigo, Fukumoto, Satoshi, Nakashima, Misako, Akamine, Akifumi, Nonaka, Kazuaki, Ohishi, Masamichi
• Format: Journal Article
• Language: English
• Published: 01.04.2005
• ISSN: 0012-1592; 1440-169X
• DOI: 10.1111/j.1440-169x.2005.00790.x

Several members of the transforming growth factor (TGF)- beta superfamily are expressed in developing teeth from the initiation stage through adulthood. Of those, TGF- beta 1 regulates odontoblast differentiation and dentin extracellular matrix synthesis. However, the molecular mechanism of TGF- beta 3 in dental pulp cells is not clearly understood. In the present study, beads soaked with human recombinant TGF- beta 3 induced ectopic mineralization in dental pulp from fetal mouse tooth germ samples, which increased in a dose-dependent manner. Further, TGF- beta 3 promoted mRNA expression, and increased protein levels of osteocalcin (OCN) and type I collagen (COL I) in dental pulp cells. We also observed that the expression of dentin sialophosphoprotein and dentin matrix protein 1 was induced by TGF- beta 3 in primary cultured dental pulp cells, however, not in calvaria osteoblasts, whereas OCN, osteopontin and osteonectin expression was increased after treatment with TGF- beta 3 in both dental pulp cells and calvaria osteoblasts. Dentin sialoprotein was also partially detected in the vicinity of TGF- beta 3 soaked beads in vivo. These results indicate for the first time that TGF- beta 3 induces ectopic mineralization through upregulation of OCN and COL I expression in dental pulp cells, and may regulate the differentiation of dental pulp stem cells to odontoblasts.