TGF-[beta] and Physiological Root Resorption of Deciduous Teeth

• Published in: International journal of molecular sciences Vol. 18; no. 1; p. 49
• Main Authors: Shimazaki, Emi, Karakida, Takeo, Yamamoto, Ryuji, Kobayashi, Saeko, Fukae, Makoto, Yamakoshi, Yasuo, Asada, Yoshinobu
• Format: Journal Article
• Language: English
• Published: 01.01.2017
• ISSN: 1422-0067
• DOI: 10.3390/ijms18010049

The present study was performed to examine how transforming growth factor [beta] (TGF-[beta]) in root-surrounding tissues on deciduous teeth regulates the differentiation induction into odontoclasts during physiological root resorption. We prepared root-surrounding tissues with (R) or without (N) physiological root resorption scraped off at three regions (R1-R3 or N1-N3) from the cervical area to the apical area of the tooth and measured both TGF-[beta] and the tartrate-resistant acid phosphatase (TRAP) activities. The TGF-[beta] activity level was increased in N1-N3, whereas the TRAP activity was increased in R2 and R3. In vitro experiments for the receptor activator of nuclear factor-[kappa]B (NF-[kappa]B) ligand (RANKL)-mediated osteoclast differentiation revealed that proteins from N1-N3 and R1-R3 enhanced the TRAP activity in RAW264 cells. A genetic study indicated that the mRNA levels of TGF-[beta]1 in N1 and N2 were significantly increased, and corresponded with levels of osteoprotegerin (OPG). In contrast, the expression level of RANKL was increased in R2 and R3. Our findings suggest that TGF-[beta] is closely related to the regulation of OPG induction and RANKL-mediated odontoclast differentiation depending on the timing of RANKL and OPG mRNA expression in the root-surrounding tissues of deciduous teeth during physiological root resorption.