title: Bacterial lipopolysaccharide induces osteoclast formation in RAW 264.7 macrophage cells.
abstract: Lipopolysaccharide (LPS) is a potent bone resorbing factor. The effect of LPS on osteoclast formation was examined by using murine RAW 264.7 macrophage cells. LPS-induced the formation of multinucleated giant cells (MGC) in RAW 264.7 cells 3 days after the exposure. MGCs were positive for tartrate-resistant acid phosphatase (TRAP) activity. Further, MGC formed resorption pits on calcium-phosphate thin film that is a substrate for osteoclasts. Therefore, LPS was suggested to induce osteoclast formation in RAW 264.7 cells. LPS-induced osteoclast formation was abolished by anti-tumor necrosis factor (TNF)-alpha antibody, but not antibodies to macrophage-colony stimulating factor (M-CSF) and receptor activator of nuclear factor (NF)-kappaB ligand (RANKL). TNF-alpha might play a critical role in LPS-induced osteoclast formation in RAW 264.7 cells. Inhibitors of NF-kappaB and stress activated protein kinase (SAPK/JNK) prevented the LPS-induced osteoclast formation. The detailed mechanism of LPS-induced osteoclast formation is discussed.
authors.affiliation: Department of Microbiology and Immunology, Aichi Medical University School of Medicine, Nagakute, Aichi 480-1195, Japan.
authors.forename: Shamima
authors.initials: S
authors.lastname: Islam
authors.forename: Ferdaus
authors.initials: F
authors.lastname: Hassan
authors.forename: Gantsetseg
authors.initials: G
authors.lastname: Tumurkhuu
authors.forename: Jargalsaikhan
authors.initials: J
authors.lastname: Dagvadorj
authors.forename: Naoki
authors.initials: N
authors.lastname: Koide
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Naiki
authors.forename: Isamu
authors.initials: I
authors.lastname: Mori
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Yoshida
authors.forename: Takashi
authors.initials: T
authors.lastname: Yokochi
mesh_terms: D000818:Animals; D001862:Bone Resorption / Q000378:metabolism* / Q000473:pathology; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D002460:Cell Line; D004926:Escherichia coli / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000008:administration & dosage / Q000378:metabolism*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D010010:Osteoclasts / Q000187:drug effects* / Q000473:pathology*
chemical_list: D008070:Lipopolysaccharides