title: Optimal compressive force induces bone formation via increasing bone sialoprotein and prostaglandin E(2) production appropriately.
abstract: 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.
authors.affiliation: Department of Orthodontics, Nihon University School of Dentistry, 1-8-13, Kanda Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
authors.forename: Narihiro
authors.initials: N
authors.lastname: Mitsui
authors.forename: Naoto
authors.initials: N
authors.lastname: Suzuki
authors.forename: Masao
authors.initials: M
authors.lastname: Maeno
authors.forename: Kotoe
authors.initials: K
authors.lastname: Mayahara
authors.forename: Momoko
authors.initials: M
authors.lastname: Yanagisawa
authors.forename: Kichibee
authors.initials: K
authors.lastname: Otsuka
authors.forename: Noriyoshi
authors.initials: N
authors.lastname: Shimizu
mesh_terms: 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
chemical_list: D008565:Membrane Proteins; D012795:Sialoglycoproteins; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D015232:Dinoprostone; D002118:Calcium