title: Different inhibitory actions of immunomodulating agents and immunosuppressive agents on bone resorption of mouse calvaria.
abstract: In this study, we have investigated the in vitro effects of the immunomodulators lobenzarit and traxanox and a newly synthesized immunosuppressant, mizoribine, as well as cyclosporin A, on bone resorption using neonatal mouse calvariae labelled with 45Ca. As stimulators of bone resorption, bovine parathyroid hormone (PTH), lipopolysaccharide (LPS), interleukin 1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) were used. Lobenzarit, traxanox, mizoribine and cyclosporin A inhibited or tended to inhibit bone resorption stimulated by PTH, LPS, IL-1 beta or TNF-alpha in a dose-dependent manner. Basal bone resorption was inhibited by immunosuppressant cyclosporin A or mizoribine, while immunomodulators lobenzarit and traxanox failed to inhibit basal bone resorption. Removal of lobenzarit from the culture medium resulted in the recovery of bone resorptive activity. These results suggest that the inhibitory effect of immunomodulators on bone resorption is reversible and nonselective. Also, it raises the possibility that immunomodulators and immunosuppressants may affect bone resorption by different mechanisms.
authors.affiliation: Third Department of Internal Medicine, St Marianna University School of Medicine, Kawasaki, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Sasagawa
authors.forename: S
authors.initials: S
authors.lastname: Fujibayashi
authors.forename: K
authors.initials: K
authors.lastname: Okano
authors.forename: C
authors.initials: C
authors.lastname: Nawa
authors.forename: S
authors.initials: S
authors.lastname: Suzuki
authors.forename: S
authors.initials: S
authors.lastname: Kou
authors.forename: Y
authors.initials: Y
authors.lastname: Yamada
authors.forename: K
authors.initials: K
authors.lastname: Someya
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D001862:Bone Resorption / Q000139:chemically induced / Q000517:prevention & control*; D002867:Chromones / Q000494:pharmacology; D003524:Cyclosporins / Q000494:pharmacology; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D066298:In Vitro Techniques; D007375:Interleukin-1 / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D051379:Mice; D008813:Mice, Inbred ICR; D010281:Parathyroid Hormone / Q000494:pharmacology; D012263:Ribonucleosides / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D062367:ortho-Aminobenzoates / Q000494:pharmacology
chemical_list: D000276:Adjuvants, Immunologic; D002867:Chromones; D003524:Cyclosporins; D007166:Immunosuppressive Agents; D007375:Interleukin-1; D008070:Lipopolysaccharides; D010281:Parathyroid Hormone; D012263:Ribonucleosides; D014409:Tumor Necrosis Factor-alpha; D062367:ortho-Aminobenzoates; C010052:mizoribine; C015735:lobenzarit; C020178:traxanox