Optimal compressive force induces bone formation via increasing bone sialoprotein and prostaglandin E(2) production appropriately.
Although orthodontic tooth movement can promote bone formation, the molecular mechanism that underlies this phenomenon is not fully understood. The purposes of this study were to determine how mechanical stress affects the osteogenic response of human osteoblastic cells (Saos-2), and also examine the optimal compression for osteogenesis in vitro. Saos-2 cells cultured with or without continuously compressive force (0.5 approximately 3.0 g/cm(2)). The expression of bone sialoprotein (BSP), osteopontin, and cyclooxygenase-2 (COX-2) were measured using real-time PCR, Western blot analysis and immunoassay. The calcium content in the mineralized nodules was determined using Calcium C-Test kit. Only one loading with 1.0 g/cm(2) of compressive force significantly increased the expression of BSP mRNA and protein, COX-2 mRNA expression and PGE(2) synthesis. Indomethacin, an inhibitor of PGE(2) synthesis, inhibited the compression-induced above phenomenon. Moreover, the conditioned medium from 1.0 g/cm(2) of compressive force apparently stimulated calcium content in mineralized nodules. This study demonstrates that an optimal compressive force stimulates in vitro mineralization by BSP synthesis through the autocrin action of PGE(2) production.
Mitsui
Narihiro
N
Department of Orthodontics, Nihon University School of Dentistry, 1-8-13, Kanda Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
Suzuki
Naoto
N
Maeno
Masao
M
Mayahara
Kotoe
K
Yanagisawa
Momoko
M
Otsuka
Kichibee
K
Shimizu
Noriyoshi
N
D016723:Bone Remodeling / Q000502:physiology*; D001862:Bone Resorption / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D051546:Cyclooxygenase 2; D015232:Dinoprostone / Q000096:biosynthesis*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D008565:Membrane Proteins; D010006:Osteoblasts / Q000378:metabolism*; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012795:Sialoglycoproteins / Q000096:biosynthesis*; D013314:Stress, Mechanical
D008565:Membrane Proteins; D012795:Sialoglycoproteins; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D015232:Dinoprostone; D002118:Calcium