Osteoprotegerin ligand modulates murine osteoclast survival in vitro and in vivo.

Osteoprotegerin ligand (OPGL) targets osteoclast precursors and osteoclasts to enhance differentiation and activation, however, little is known about OPGL effects on osteoclast survival. In vitro, the combination of OPGL + colony-stimulating factor-1 (CSF-1) is required for optimal osteoclast survival. Ultrastructurally, apoptotic changes were observed in detached cells and culture lysates exhibited elevated caspase 3 activity, particularly in cultures lacking CSF-1. DEVD-FMK (caspase 3 inhibitor) partially protected cells when combined with OPGL, but not when used alone or in combination with CSF-1. CSF-1 maintained NF-kappaB activation and increased the expression of bcl-2 and bcl-X(L) mRNA, but had no effect on JNK activation. In contrast, OPGL enhanced both NF-kappaB and JNK kinase activation and increased the expression of c-src, but not bcl-2 and bcl-X(L) mRNA. These data suggest that aspects of both OPGL's and CSF-1's signaling/survival pathways are required for optimal osteoclast survival. In mice, a single dose of OPG, the OPGL decoy receptor, led to a >90% loss of osteoclasts because of apoptosis within 48 hours of exposure without impacting osteoclast precursor cells. Therefore, OPGL is essential, but not sufficient, for osteoclast survival and endogenous CSF-1 levels are insufficient to maintain osteoclast viability in the absence of OPGL.

[1]  S. Nishikawa,et al.  The murine mutation osteopetrosis is in the coding region of the macrophage colony stimulating factor gene , 1990, Nature.

[2]  Ruedi Aebersold,et al.  Molecular characterization of mitochondrial apoptosis-inducing factor , 1999, Nature.

[3]  C. Rauch,et al.  Tumoricidal activity of tumor necrosis factor–related apoptosis–inducing ligand in vivo , 1999, Nature Medicine.

[4]  Chambers Tj The cellular basis of bone resorption. , 1980 .

[5]  E. Jimi,et al.  Macrophage colony-stimulating factor and interleukin-1 alpha maintain the survival of osteoclast-like cells. , 1995, Endocrinology.

[6]  E. Jimi,et al.  Osteoclast differentiation factor acts as a multifunctional regulator in murine osteoclast differentiation and function. , 1999, Journal of immunology.

[7]  Ulrich Siebenlist,et al.  Requirement for NF-κB in osteoclast and B-cell development , 1997 .

[8]  R. Steinman,et al.  TRANCE (Tumor Necrosis Factor [TNF]-related Activation-induced Cytokine), a New TNF Family Member Predominantly Expressed in T cells, Is a Dendritic Cell–specific Survival Factor , 1997, The Journal of experimental medicine.

[9]  John C. Lee,et al.  Osteoprotegerin Is a Receptor for the Cytotoxic Ligand TRAIL* , 1998, The Journal of Biological Chemistry.

[10]  D. Lacey,et al.  Osteoclast markers accumulate on cells developing from human peripheral blood mononuclear precursors , 1999, Journal of cellular biochemistry.

[11]  R. Dubose,et al.  A homologue of the TNF receptor and its ligand enhance T-cell growth and dendritic-cell function , 1997, Nature.

[12]  S. Patterson,et al.  Selective Activation of Caspases During Apoptotic Induction in HL-60 Cells , 1997, The Journal of Biological Chemistry.

[13]  S. Mochizuki,et al.  Identity of osteoclastogenesis inhibitory factor (OCIF) and osteoprotegerin (OPG): a mechanism by which OPG/OCIF inhibits osteoclastogenesis in vitro. , 1998, Endocrinology.

[14]  T. Suda,et al.  Caspases (interleukin-1beta-converting enzyme family proteases) are involved in the regulation of the survival of osteoclasts. , 1998, Bone.

[15]  R. Gascoyne,et al.  Immunohistochemical analysis of in vivo patterns of expression of CPP32 (Caspase-3), a cell death protease. , 1997, Cancer research.

[16]  T. Komori,et al.  Potential role of cbfa1, an essential transcriptional factor for osteoblast differentiation, in osteoclastogenesis: regulation of mRNA expression of osteoclast differentiation factor (ODF). , 1998, Biochemical and biophysical research communications.

[17]  V. Cryns,et al.  Proteases to die for. , 1998, Genes & development.

[18]  D. Lacey,et al.  The Ligand for Osteoprotegerin (OPGL) Directly Activates Mature Osteoclasts , 1999, The Journal of cell biology.

[19]  K Yano,et al.  Osteoclast differentiation factor is a ligand for osteoprotegerin/osteoclastogenesis-inhibitory factor and is identical to TRANCE/RANKL. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[20]  David L. Brautigan,et al.  Raf-1 activates MAP kinase-kinase , 1992, Nature.

[21]  D. Lacey,et al.  Osteoprotegerin Ligand Is a Cytokine that Regulates Osteoclast Differentiation and Activation , 1998, Cell.

[22]  S. Clark,et al.  Macrophage colony-stimulating factor stimulates survival and chemotactic behavior in isolated osteoclasts , 1993, The Journal of experimental medicine.

[23]  E. White,et al.  Life, death, and the pursuit of apoptosis. , 1996, Genes & development.

[24]  E. Jimi,et al.  Activation of NF-κB Is Involved in the Survival of Osteoclasts Promoted by Interleukin-1* , 1998, The Journal of Biological Chemistry.

[25]  S. Morony,et al.  Tumor necrosis factor receptor family member RANK mediates osteoclast differentiation and activation induced by osteoprotegerin ligand. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[26]  C. Ohlsson,et al.  Osteoprotegerin mRNA is expressed in primary human osteoblast-like cells: down-regulation by glucocorticoids. , 1998, The Journal of endocrinology.

[27]  D. Lacey,et al.  Osteoprotegerin and osteoprotegerin ligand effects on osteoclast formation from human peripheral blood mononuclear cell precursors , 1999, Journal of cellular biochemistry.

[28]  G Shimamoto,et al.  Osteoprotegerin: A Novel Secreted Protein Involved in the Regulation of Bone Density , 1997, Cell.

[29]  Brian R. Wong,et al.  TRANCE Is a Novel Ligand of the Tumor Necrosis Factor Receptor Family That Activates c-Jun N-terminal Kinase in T Cells* , 1997, The Journal of Biological Chemistry.