IL-17 is a newly discovered T cell-derived cytokine whose role in osteoclast development has not been fully elucidated. Treatment of cocultures of mouse hemopoietic cells and primary osteoblasts with recombinant human IL-17 induced the formation of multinucleated cells, which satisfied major criteria of osteoclasts, including tartrate-resistant acid phosphatase activity, calcitonin receptors, a...

MicroRNA (miR)-150 has been shown to control B and T cell differentiation in the bone marrow. The regulation of B and T cells is directly or systematically associated with bone remodeling cells such as osteoclasts; however, the functional role of miR-150 in bone homeostasis has not been well studied. Here, we observed down-regulation of miR-150 during in vitro osteoclast differentiation and, fu...

Receptor activator of nuclear factor-kappaB ligand (RANKL)-induced signals play critical roles in osteoclast differentiation and function. SB203580, an inhibitor of p38 MAPK, blocked osteoclast formation induced by 1alpha,25-dihydroxyvitamin D(3) and prostaglandin E(2) in cocultures of mouse osteoblasts and bone marrow cells. Nevertheless, SB203580 showed no inhibitory effect on RANKL expressio...

Cells with monocyte/macrophage lineage expressing receptor activator of NF-κB (RANK) differentiate into osteoclasts following stimulation with the RANK ligand (RANKL). Cell adhesion signaling is also required for osteoclast differentiation from precursors. However, details of the mechanism by which cell adhesion signals induce osteoclast differentiation have not been fully elucidated. To invest...

The effects of mechanical stress release on osteoclastogenesis may be as important as those of mechanical stress application. However, the direct effects of mechanical stress on the behavior of osteoclasts has not been thoroughly investigated and there is limited information on the results of the release from mechanical stress. In this study, the effects of mechanical stress application and its...

Introduction Autosomal Recessive Osteopetrosis (ARO) is a severe bone disease characterized by increased bone density due to impairment in osteoclast bone resorptive function (osteoclast-rich forms) or differentiation (osteoclast-poor forms). The latter form carries mutations in Tnfsf11 gene, which codifies for the receptor activator of NFB ligand (RANKL), an essential cytokine expressed in str...

The aim of this study was to clarify the role of monosodium urate (MSU) crystals in receptor activator of nuclear factor kB ligand- (RANKL-) RANK-induced osteoclast formation. RAW 264.7 murine macrophage cells were incubated with MSU crystals or RANKL and differentiated into osteoclast-like cells as confirmed by staining for tartrate-resistant acid phosphatase (TRAP) and actin ring, pit formati...

To investigate 1α,25-(OH)₂D₃ regulation of matrix metalloproteinase-9 (MMP-9) protein expression during osteoclast formation and differentiation, receptor activator of nuclear factor kB ligand (RANKL) and macrophage colony-stimulating factor (M-CSF) were administered to induce the differentiation of RAW264.7 cells into osteoclasts. The cells were incubated with different concentrations of 1α,25...

BACKGROUND Excessive osteoclast activity is a major cause of metabolic bone disorders, such as osteopenia, rheumatoid arthritis, and osteoporosis. Thus, discovery of agents targeting osteoclast differentiation and bone resorption is important for development of novel treatments for bone diseases. It has been demonstrated that ethanolic extract of schizonepeta tenuifolia (EEST) has potent anti-o...

We have shown recently that by acting on the thyroid-stimulating hormone (TSH) receptor (TSHR), TSH negatively regulates osteoclast differentiation. Both heterozygotic and homozygotic TSHR null mice are osteopenic with evidence of enhanced osteoclast differentiation. Here, we report that the accompanying elevation of TNF , an osteoclastogenic cytokine, causes the increased osteoclast differenti...