title: Calcium/calmodulin-dependent kinase activity is required for efficient induction of osteoclast differentiation and bone resorption by receptor activator of nuclear factor kappa B ligand (RANKL).
abstract: Calcium/calmodulin-dependent protein kinase (CaMK) is a major down stream mediator of Ca(2+) signaling in a wide range of cellular functions, including ion channel and cell cycle regulation and neurotransmitter synthesis and release. Here we have investigated the role of the CaMK signaling pathway in osteoclast differentiation and bone resorption. We observed that the CaMKI, CaMKII gamma isoforms were present in both bone-marrow derived macrophages and RAW264.7 murine macrophage cell line, and that expression persisted during osteoclast differentiation in the presence of receptor activator of nuclear factor kappa B (NF-kappaB) ligand (RANKL). RANKL-induced differentiation was accompanied by increased cyclic AMP response element transcriptional activity, and ERK phosphorylation, which are both downstream targets of CaMK. Two selective inhibitors of CaMKs, KN-93 and KN-62, inhibited osteoclastogenesis in a time and concentration-dependent manner. This was accompanied by suppression of cathepsin K expression and osteoclastic bone resorption, which are markers for differentiated osteoclast function. KN-93 and KN-62 both inhibited RANKL-induced ERK phosphorylation and CREB transcriptional activity. These findings imply a role for CaMK in osteoclast differentiation and bone resorption.
authors.affiliation: Molecular Orthopedic Laboratory, School of Surgery and Pathology, University of Western Australia, Nedlands, WA, Australia.
authors.forename: Estabelle S M
authors.initials: ES
authors.lastname: Ang
authors.forename: Ping
authors.initials: P
authors.lastname: Zhang
authors.forename: James H
authors.initials: JH
authors.lastname: Steer
authors.forename: Jamie W-Y
authors.initials: JW
authors.lastname: Tan
authors.forename: Kirk
authors.initials: K
authors.lastname: Yip
authors.forename: Ming H
authors.initials: MH
authors.lastname: Zheng
authors.forename: David A
authors.initials: DA
authors.lastname: Joyce
authors.forename: Jiake
authors.initials: J
authors.lastname: Xu
mesh_terms: D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D001596:Benzylamines / Q000494:pharmacology; D001862:Bone Resorption / Q000201:enzymology / Q000235:genetics / Q000378:metabolism* / Q000517:prevention & control; D020013:Calcium Signaling / Q000187:drug effects; D054729:Calcium-Calmodulin-Dependent Protein Kinase Type 1; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D056657:Cathepsin K; D002403:Cathepsins / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D008264:Macrophages / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D010010:Osteoclasts / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D053245:RANK Ligand / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013449:Sulfonamides / Q000494:pharmacology; D013997:Time Factors; D014158:Transcription, Genetic; D014162:Transfection; D000096926:Benzenesulfonamides
chemical_list: D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D001596:Benzylamines; D054729:Calcium-Calmodulin-Dependent Protein Kinase Type 1; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D056657:Cathepsin K; D002403:Cathepsins; D017362:Cyclic AMP Response Element-Binding Protein; D048049:Extracellular Signal-Regulated MAP Kinases; D047428:Protein Kinase Inhibitors; D053245:RANK Ligand; D012333:RNA, Messenger; D013449:Sulfonamides; C492004:Creb1 protein, mouse; C505689:Tnfsf11 protein, mouse; C072105:KN 93; D000096926:Benzenesulfonamides; C063302:KN 62; C517598:Camk1 protein, mouse; C517599:Camk1 protein, rat; C517681:Pnck protein, mouse; C517682:Pnck protein, rat; C534132:Ctsk protein, mouse; C534133:Ctsk protein, rat