RRC ID 41431
Author Quinn JM, Itoh K, Udagawa N, Hausler K, Yasuda H, Shima N, Mizuno A, Higashio K, Takahashi N, Suda T, Martin TJ, Gillespie MT.
Title Transforming growth factor beta affects osteoclast differentiation via direct and indirect actions.
Journal J. Bone Miner. Res.
Abstract Transforming growth factor beta (TGF-beta) is abundant in bone and has complex effects on osteolysis, with both positive and negative effects on osteoclast differentiation, suggesting that it acts via more than one mechanism. Osteoclastogenesis is determined primarily by osteoblast (OB) expression of the tumor necrosis factor (TNF)-related molecule receptor activator of NF-kappaB ligand (RANKL) and its decoy receptor osteoprotegerin (OPG), which are increased and decreased, respectively, by osteolytic factors. A RANKL-independent osteoclastogenic mechanism mediated by TNF-alpha has also been shown. Therefore, we investigated TGF-beta effects on osteoclast formation in culture systems in which osteoclastogenic stimulus is dependent on OBs and culture systems where it was provided by exogenously added RANKL or TNF-alpha. Both OPG and TGF-beta inhibited osteoclast formation in hemopoietic cell/OB cocultures, but the kinetics of their action differed. TGF-beta also inhibited osteoclastogenesis in cocultures of cells derived from OPG null (opg-/-) mice. TGF-beta strongly decreased RANKL messenger RNA (mRNA) expression in cultured osteoblasts, and addition of exogenous RANKL to TGFbeta-inhibited cocultures of opg-/- cells partially restored osteoclastogenesis. Combined, these data indicate that the inhibitory actions of TGF-beta were mediated mainly by decreased OB production of RANKL. In contrast, in the absence of OBs, TGF-beta greatly increased osteoclast formation in recombinant RANKL- or TNF-alpha-stimulated cultures of hemopoietic cells or RAW 264.7 macrophage-like cells to levels several-fold greater than attainable by maximal stimulation by RANKL or TNF-alpha. These data suggest that TGF-beta may increase osteoclast formation via action on osteoclast precursors. Therefore, although RANKL (or TNF-alpha) is essential for osteoclast formation, factors such as TGF-beta may powerfully modify these osteoclastogenic stimuli. Such actions may be critical to the control of physiological and pathophysiological osteolysis.
Volume 16(10)
Pages 1787-94
Published 2001-10
DOI 10.1359/jbmr.2001.16.10.1787
PMID 11585342
MeSH Animals Carrier Proteins / genetics Carrier Proteins / metabolism* Carrier Proteins / pharmacology Cell Differentiation / drug effects Cells, Cultured Coculture Techniques Glycoproteins / genetics Glycoproteins / metabolism* Glycoproteins / pharmacology Membrane Glycoproteins / genetics Membrane Glycoproteins / metabolism* Membrane Glycoproteins / pharmacology Mice Mice, Inbred C57BL Mice, Knockout Osteoclasts / cytology Osteoclasts / drug effects Osteoclasts / metabolism* Osteoprotegerin RANK Ligand Receptor Activator of Nuclear Factor-kappa B Receptors, Cytoplasmic and Nuclear / genetics Receptors, Cytoplasmic and Nuclear / metabolism* Receptors, Tumor Necrosis Factor Spleen / cytology Transforming Growth Factor beta / metabolism* Transforming Growth Factor beta / pharmacology Tumor Necrosis Factor-alpha / metabolism* Tumor Necrosis Factor-alpha / pharmacology
IF 6.314
Times Cited 150
Human and Animal Cells