RRC ID 3868
著者 Tsubaki M, Kato C, Manno M, Ogaki M, Satou T, Itoh T, Kusunoki T, Tanimori Y, Fujiwara K, Matsuoka H, Nishida S.
タイトル Macrophage inflammatory protein-1alpha (MIP-1alpha) enhances a receptor activator of nuclear factor kappaB ligand (RANKL) expression in mouse bone marrow stromal cells and osteoblasts through MAPK and PI3K/Akt pathways.
ジャーナル Mol Cell Biochem
Abstract Osteolytic lesions are rapidly progressive during the terminal stages of myeloma, and the bone pain or bone fracture that occurs at these lesions decreases the patients' quality of life to a notable degree. In relation to the etiology of this bone destruction, it has been reported recently that MIP-1alpha, produced in large amounts in myeloma patients, acts indirectly on osteoclastic precursor cells, and activates osteoclasts by way of bone-marrow stromal cells or osteoblasts, although the details of this process remain obscure. In the present study, our group investigated the mechanism by which RANKL expression is induced by MIP-1alpha and the effects of MIP-1alpha on the activation of osteoclasts. RANKL mRNA and RANKL protein expressions increased in both ST2 cells and MC3T3-E1 cells in a MIP-1alpha concentration-dependent manner. RANKL mRNA expression began to increase at 1 h after the addition of MIP-1alpha; the increase became remarkable at 2 h, and continuous expression was observed subsequently. Both ST2 and MC3T3-E1 cells showed similar levels of increased RANKL protein expression at 1, 2, and 3 days after the addition of MIP-1alpha. After the addition of MIP-1alpha, the amount of phosphorylated ERK1/2 and Akt protein expressions showed an increase, as compared to the corresponding amount in the control group. On the other hand, the amount of phosphorylated p38MAPK protein expression showed a decrease from the amount in the control group after the addition of MIP-1alpha. U0126 (a MEK1/2 inhibitor) or LY294002 (a PI3K inhibitor) was added to ST2 and MC3T3-E1 cells, and was found to inhibit RANKL mRNA and RANKL protein expression in these cells. When SB203580, a p38MAPK inhibitor, was added, RANKL mRNA and RANKL protein expression were increased in these cells. MIP-1alpha was found to promote osteoclastic differentiation of C7 cells, an osteoclastic precursor cell line, in a MIP-1alpha concentration-dependent manner. MIP-1alpha promoted differentiation into osteoclasts more extensively in C7 cells incubated together with ST2 and MC3T3-E1 cells than in C7 cells incubated alone. These results suggested that MIP-1alpha directly acts on the osteoclastic precursor cells and induces osteoclastic differentiation. This substance also indirectly induces osteoclastic differentiation through the promotion of RANKL expression in bone-marrow stromal cells and osteoblasts. The findings of this investigation suggested that activation of the MEK/ERK and the PI3K/Akt pathways and inhibition of p38MAPK pathway were involved in RANKL expression induced by MIP-1alpha in bone-marrow stromal cells and osteoblasts. This finding may be useful in the development of an osteoclastic inhibitor that targets intracellular signaling factors.
巻・号 304(1-2)
ページ 53-60
公開日 2007-10-1
DOI 10.1007/s11010-007-9485-7
PMID 17549607
MeSH Animals Bone Marrow Cells / drug effects* Bone Marrow Cells / metabolism Butadienes / pharmacology Cell Differentiation / drug effects Cells, Cultured Chemokine CCL3 / pharmacology* Chromones / pharmacology Enzyme Inhibitors / pharmacology Extracellular Signal-Regulated MAP Kinases / metabolism* Imidazoles / pharmacology Mice Morpholines / pharmacology Nitriles / pharmacology Oncogene Protein v-akt / metabolism* Osteoblasts / drug effects* Osteoblasts / metabolism Osteoclasts / cytology Osteoclasts / drug effects Phosphatidylinositol 3-Kinases / metabolism* Phosphorylation / drug effects Pyridines / pharmacology RANK Ligand / genetics* RANK Ligand / metabolism Signal Transduction / drug effects Stromal Cells / drug effects Stromal Cells / metabolism
IF 2.795
引用数 52
WOS 分野 CELL BIOLOGY
リソース情報
ヒト・動物細胞 ST2(RCB0224) MC3T3-E1(RCB1126)