Distinctive anabolic roles of 1,25-dihydroxyvitamin D3 and parathyroid hormone in teeth and mandible versus long bones

作者：Liu, Hong; Guo, Jian; Wang, Lin; Chen, Ning; Karaplis, Andrew; Goltzman, David; Miao, Dengshun^*

来源：Journal of Endocrinology, 2009, 203(2): 203-213.

DOI：10.1677/JOE-09-0247

• D-DEPENDENT RICKETS
• VITAMIN-D-RECEPTOR
• AGED OVARIECTOMIZED RATS
• MINERAL ION HOMEOSTASIS
• 25-HYDROXYVITAMIN-D 1-ALPHA-HYDROXYLASE
• HYP MICE
• SKELETAL
• CALCIUM
• GENE
• INACTIVATION

To assess the roles of 1,25-dihydroxyvitamin D (1,25(OH)(2)D) and parathyroid hormone (PTH) in hard tissue formation in oro-facial tissues, we examined the effect of either 1,25(OH)(2)D or PTH deficiency on dentin and dental alveolar bone formation and mineralization in the mandibles, and osteoblastic bone formation in long bones of 1 alpha-hydroxylase knockout (1 alpha(OH)ase(-/-)) mice. Compared with wild-type mice, the mineral density was decreased in the teeth and mandibles, and unmineralized dentin (predentin and biglycan immunopositive dentin) and unmineralized bone matrix in the dental alveolar bone were increased in 1 alpha(OH)ase(-/-) mice. The dental volume, reparative dentin volume, and dentin sialoprotein immunopositive areas were reduced in 1 alpha(OH)ase(-/-) mice. The cortical thickness, dental alveolar bone volume, and osteoblast number were all decreased significantly in the mandibles; in contrast, the osteoblast number and Surface were increased in the trabecular bone of the tibiae in 1 alpha(OH)ase(-/-) mice consistent with their secondary hyperparathyroidism. The expression of PTH receptor and IGF1 was reduced slightly in mandibles, but enhanced significantly in the long bones in the 1 alpha(OH)ase(-/-) mice. To control for the role of secondary hyperparathyroidism, we also examined teeth and mandibles in 6-week-old PTH-/- mice. In these animals, dental and bone volumes in mandibles were not altered when compared with their wild-type littermates. These results Suggest that 1,25(OH)(2)D-3 plays an anabolic role ill both dentin and dental alveolar bone as it does ill long bones, whereas PTH acts predominantly in long bones rather than mandibular bone. Journal of Endocrinology (2009) 203, 203-213

• 出版日期2009-11
• 单位南京医科大学