1853-PUB: Extrapancreatic Effects of GIP on Bone

Abstract

Glucose-dependent insulinotropic polypeptide (GIP) exhibits extrapancreatic effects through the receptor for GIP (GIPR). In this study, we used Ni-Ti Closed Coil Spring (Ni-Ti) in GIPR-deficient mice (GIPRKO) and wild-type mice (WT) to investigate the effect of GIP on force-induced bone remodeling due to orthodontic tooth movement. It was investigated. Ni-Ti was attached between the maxillary bone and the maxillary left first molar (M1) of GIPRKO and WT, and mechanical load was applied by pulling the M1 in the mesial direction. Remaining amount and bone quality were measured. A histological examination of the maxilla was also performed. As a result, compared to WT, GIPRKO showed a significant increase in tooth movement distance and a significant decrease in residual alveolar bone mass. TRAP staining showed an increase in osteoclasts in GIPRKO compared to WT on the tooth moving side. We also found that GIPRKO reduced osteoblasts in the steady state and suppressed osteoblasts after tooth movement. These results suggest that GIPRK impairs bone remodeling through increased bone resorption due to mechanical load, and that GIP plays an important role in bone remodeling. Disclosure T.Yamauchi: None. S.Goto: None. K.Naruse: None. N.Nakamura: None. M.Miyabe: None. M.Ito: None. R.Hoshino: None. S.Kanada: None. T.Sekiya: None. T.Matsubara: None. K.Miyazawa: None.