副甲状腺ホルモン間欠的投与による骨膜細胞の増殖および分化に与える影響

抄録

Bone regenerative medicine is an important dental implant treatment for cases with severe ridge resorption. We have been attempting to use autogeneous periosteum as a biomaterial for bone regeneration. In the present study, we evaluated the effects of intermittent injection of human parathyroid hormone (hPTH) prior to harvesting the periosteum, on the proliferation and differentiation of osteoblasts.
Using male Wistar rats, hPTH (1-34) (100 μg/kg) in physiological saline and physiological saline were intraperitoneally injected three times a week to the experimental and control groups, respectively. Then, circular pieces of pericranium 4 mm in diameter were harvested from the top of the cranium bone. The harvested periosteum pieces were cultured for 14 days and compared between the experimental and control groups.
Compared with the control group, the experimental group had a significantly greater increase in cell numbers and alkaline phosphatase (ALP) densely positive area. In the experimental group, on 7 days and 14 days proliferating cell nuclear antigen (PCNA)-positive and runt-related transcription factor 2 (RUNX2)-positive cells were observed. In addition, real-time PCR showed significant increases in bone morphogenetic protein 2 (BMP2), type I collagen (Col-I), ALP, osteonectin (ON), osteopontin (OPN), and osteocalcin (OC).
These results indicate that increased proliferation and differentiation of osteoblasts in the periosteum harvested from rats with intermittent injection of hPTH were observed in a short period of time in a culture system. We conclude that this type of periosteum can be used clinically for bone regenerative treatment as an autogeneous biomaterial.