| First Author | Lee JE | Year | 2007 |
| Journal | Exp Hematol | Volume | 35 |
| Issue | 7 | Pages | 1100-8 |
| PubMed ID | 17588479 | Mgi Jnum | J:123060 |
| Mgi Id | MGI:3717017 | Doi | 10.1016/j.exphem.2007.04.006 |
| Citation | Lee JE, et al. (2007) Stimulation of osteoclastogenesis by enhanced levels of MIP-1alpha in BALB/c mice in vitro. Exp Hematol 35(7):1100-8 |
| abstractText | OBJECTIVES: We compared osteoclast (OC) formation in bone marrow-derived macrophages (BMM) from C57BL/6 (B/6) and BALB/c (B/c) mice. After stimulation of receptor activator of nuclear factor-kappaB ligand (RANKL), enhanced OC formation and higher level of macrophage inflammatory protein-1alpha (MIP-1alpha) were observed in the BMM from B/c mice. In this study, we determined whether MIP-1alpha is responsible for stimulated OC formation in the BMM. MATERIALS AND METHODS: OC formation was evaluated in BMM. Expression of MIP-1alpha during OC formation was analyzed at the mRNA and protein levels. Apoptosis of mature OCs was evaluated by observing the degradation of DNA. Activation of nuclear factor-kappaB (NF-kappaB) was measured by electrophoretic mobility shift assay. RESULTS: After stimulation by RANKL expression of MIP-1alpha at the mRNA and protein levels was much higher in BMM from B/c mice than in BMM from B/6 mice. Transcripts of the MIP-1alpha receptors, CCR1 and CCR5, were present at similar levels in unstimulated BMM of the two strains. Blockade of MIP-1alpha inhibited OC formation, and exogenously added MIP-1alpha stimulated it in RANKL-stimulated BMM. MIP-1alpha affected not only the early precursors but also mature OCs. It prevented apoptosis of mature OCs by activating NF-kappaB, and the effect of RANKL on survival was dependent on its ability to induce MIP-1alpha. CONCLUSIONS: MIP-1alpha, induced by RANKL during OC differentiation, increases OC formation by acting on OC progenitor cells, and prolongs survival of mature OC via signaling through NF-kappaB. The enhanced OC formation in BMM from B/c mice could be due to, at least in part, to their higher levels of MIP-1alpha. |
