effect-anti-c-fms-antibody-on-osteoclast-formation-proliferation

Effect of Anti-c-fms Antibody on Osteoclast Formation and Proliferation of Osteoclast Precursor In Vitro

Bone remodeling is a complex process and it involves periods of deposition and resorption. Bone resorption is a process by which bone is broken down by ...

Tohoku University Graduate School of Dentistry

Glucagon-like peptide-1 (GLP-1) receptor agonists are an effective treatment approach for type 2 diabetes. Recently, anti-inflammatory effects of GLP-1 receptor agonists have also been reported. Lipopolysaccharide (LPS) induces inflammation and osteoclast formation. In this study, we investigated the effect of exendin-4, a widely used GLP-1 receptor agonist, in LPS-induced osteoclast formation and bone resorption. LPS with or without exendin-4 was administered on mouse calvariae by daily subcutaneous injection. The number of osteoclasts, the ratio of bone resorption pits, and the level of C-terminal cross-linked telopeptide of type I collagen (CTX) were significantly lower in LPS- and exendin-4-coadministered mice than in mice administered with LPS alone. RANKL and TNF- mRNA expression levels were lower in the exendin-4- and LPS-coadministered group than in the LPS-administered group. Our  results showed no direct effects of exendin-4 on RANKL-induced osteoclast formation, TNF--induced osteoclast formation, or LPS-induced RANKL expression in stromal cells. Conversely, TNF- mRNA expression was inhibited in the exendin-4- and LPS-cotreated macrophages compared with cells treated with LPS alone. These results indicate that the GLP-1 receptor agonist exendin-4 may inhibit LPS-induced osteoclast formation and bone resorption by inhibiting LPS-induced TNF- production in macrophages.

The Glucagon-Like Peptide-1 Receptor Agonist Exendin-4 Inhibits Lipopolysaccharide-Induced Osteoclast Formation and Bone Resorption via Inhibition of TNF- Expression in Macrophages.

C-X-C motif chemokine 12 (CXCL12) belongs to the family of CXC chemokines. Lipopolysaccharide (LPS) induces inflammation-induced osteoclastogenesis and bone resorption, and in recent years, stimulatory effects of CXCL12 on bone resorption have also been reported. In the present study, we investigated the effects of CXCL12 on LPS-induced osteoclastogenesis and bone resorption. LPS was administered with or without CXCL12 onto mouse calvariae by daily subcutaneous injection. Numbers of osteoclasts and bone resorption were significantly elevated in mice co-administered LPS and CXCL12 compared with mice administered LPS alone. Moreover, receptor activator of NF-kB ligand (RANKL) and tumor necrosis factor-α (TNF-α) mRNA levels were higher in mice co-administered LPS and CXCL12 compared with mice administered LPS alone. These in vitro results confirmed a direct stimulatory effect of CXCL12 on RANKL- and TNF-α-induced osteoclastogenesis. Furthermore, TNF-α and RANKL mRNA levels were elevated in macrophages and osteoblasts, respectively, co-treated in vitro with CXCL12 and LPS, in comparison with cells treated with LPS alone. Our results suggest that CXCL12 enhances LPS-induced osteoclastogenesis and bone resorption in vivo through a combination of increasing LPS-induced TNF-α production by macrophages, increasing RANKL production by osteoblasts, and direct enhancement of osteoclastogenesis.

C-X-C Motif Chemokine 12 Enhances Lipopolysaccharide-Induced Osteoclastogenesis and Bone Resorption In Vivo.

Dipeptidyl peptidase 4 (DPP-4) inhibition is a new therapeutic strategy for type 2 diabetic patients. DPP-4 has been reported to enhance inflammation. However, the effect of DPP-4 inhibition on inflammation remains unknown. Lipopolysaccharide (LPS) is a strong inducer of inflammation and osteoclast formation. In this study, we investigated in vivo effects of DPP-4 inhibition on LPS-induced osteoclast formation and bone resorption, as well as in vitro effects of DPP-4 inhibition on RANKL-induced osteoclastogenesis and TNF-α-induced osteoclastogenesis.

Akiko Kishikawa

Division of Orthodontics and Dentofacial Orthopedics,
Department of Translational Medicine,
Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine

Tohoku University Graduate School of Dentistry

Effect of Anti-c-fms Antibody on Osteoclast Formation and Proliferation of Osteoclast Precursor In Vitro

Akiko Kishikawa

Division of Orthodontics and Dentofacial Orthopedics,Department of Translational Medicine,Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine

Tohoku University Graduate School of Dentistry

Effect of Anti-c-fms Antibody on Osteoclast Formation and Proliferation of Osteoclast Precursor In Vitro

Division of Orthodontics and Dentofacial Orthopedics,
Department of Translational Medicine,
Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine