title: [Bone and Stem Cells. Molecular mechanisms of the differentiation and activation of osteoclasts derived from hematopoietic cells].
abstract: Mononuclear myeloid lineage cells, which are attracted to bone surfaces by chemokines and other factors, differentiate into multinucleated bone resorbing osteoclasts by cell fusion. Receptor activator of nuclear factor-κB ligand (RANKL) , which is expressed in mesenchymal cells, including osteocytes and hypertrophic chondrocytes, is essential for osteoclast differentiation and function. Osteoclasts have the capacity to resorb bone and impaired osteoclast differentiation and/or function leads to osteopetrosis, a rare disease in which mineralized bone cannot be removed. In contrast, excessive osteoclastogenesis causes diseases such as osteoporosis. Recent findings suggest that osteoclasts can also function as positive and negative regulators of osteoblastic bone formation. Thus, understanding of the molecular mechanisms that regulate osteoclastogenesis is important to develop therapeutic approaches to prevent bone diseases. This paper reviews recent findings of the molecular mechanisms regulating osteoclast differentiation and function.
authors.affiliation: Department of Cell Signaling, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Japan./Japan Science and Technology Agency, ERATO, Takayanagi Osteonetwork Project, Japan.
authors.forename: Mikihito
authors.initials: M
authors.lastname: Hayashi
authors.forename: Tomoki
authors.initials: T
authors.lastname: Nakashima
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000166:cytology / Q000378:metabolism*; D002454:Cell Differentiation / Q000502:physiology*; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D006801:Humans; D010010:Osteoclasts / Q000166:cytology / Q000378:metabolism*; D053245:RANK Ligand / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology*
chemical_list: D053245:RANK Ligand