Involvement of p38MAP kinase in bone morphogenetic protein-4-induced osteoprotegerin in mouse bone-marrow-derived stromal cells.
Osteoprotegerin (OPG)/osteoclastogenesis inhibitory factor is a recently identified cytokine that belongs to the tumour necrosis factor receptor superfamily and regulates bone mass by inhibiting osteoclastic bone resorption. This study found that bone morphogenetic protein (BMP)-4 markedly increased the level of soluble OPG in the mouse bone-marrow-derived stromal cell line, ST2. In contrast, BMP-4 showed no effect on OPG ligand production in ST2 cells under similar conditions. Using an in vitro immunocomplex kinase assay, BMP-4 was found to activate p38 mitogen-activated protein (MAP) kinase. Pre-treatment of ST2 cells with SB203580 (a specific inhibitor of p38MAP kinase) inhibited BMP-4-induced increase in OPG, although PD98059 (a specific inhibitor of classic MAP kinase cascade) showed no effect on OPG production. These results clearly suggest that activation of the p38MAP kinase pathway is necessary for BMP-4-induced OPG induction in ST2 cells.
Tazoe
Michiko
M
Department of Pharmacology, School of Dentistry, Aichi-Gakuin University, Nagoya 464-8650, Japan.
Mogi
Makio
M
Goto
Shigemi
S
Togari
Akifumi
A
D000818:Animals; D001854:Bone Marrow Cells / Q000187:drug effects* / Q000378:metabolism; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D006023:Glycoproteins / Q000096:biosynthesis*; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000502:physiology*; D053244:Osteoprotegerin; D018160:Receptors, Cytoplasmic and Nuclear / Q000096:biosynthesis*; D018124:Receptors, Tumor Necrosis Factor; D011994:Recombinant Proteins / Q000494:pharmacology; D015398:Signal Transduction / Q000502:physiology; D017154:Stromal Cells / Q000187:drug effects* / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases
C525810:Bmp4 protein, mouse; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; D006023:Glycoproteins; D053244:Osteoprotegerin; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; D011994:Recombinant Proteins; C506031:Tnfrsf11b protein, mouse; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases