title: Cyclosporine A and FK506 induce osteoclast apoptosis in mouse bone marrow cell cultures.
abstract: Studies were carried out to characterize the effects of cyclosporines and FK506 on the formation and survival of osteoclasts deriving from mouse bone marrow cultures. Cyclosporin A (CsA), cyclosporin B (CsB), cyclosporin H (CsH), and FK506 all inhibited receptor activator of NFkappaB ligand (RANKL)-stimulated tartrate-resistant acid phosphatase (TRAP) activity and generation of TRAP+ multinucleated cells in the cultures. CsA and CsG were approximately equipotent, CsH was approximately one order of magnitude less potent than the other cyclosporines, and FK506 was approximately two orders of magnitude more potent than CsA and CsG. All of the inhibitors demonstrated greater potency and efficacy on decreasing the number of TRAP+ multinucleated cells than on decreasing total TRAP activity. Further evidence that late stages were more sensitive to inhibition was obtained in experiments in which CsA was present for different segments of the RANKL-stimulated culture period. CsA was as efficacious when added for the final 2 days of a 4-day culture as when added for the entire culture period, whereas it was less effective if added for only the first 2 days of the culture. When CsA or FK506 were added for 1 day to cultures in which osteoclasts had already formed, the numbers of TRAP+ osteoclasts decreased. Treatment with CsA or FK506 produced nuclear fragmentation and disruption of the multinucleated osteoclasts and an increase in caspase-3 activity. The apoptosis inhibitor z-VAD partially prevented the inhibitory effects of CsA and FK506 on the survival of TRAP+ multinucleated cells in the cultures and also preserved the normal osteoclast morphology. The data indicate that an important component of the inhibitory effects of CsA and FK506 on marrow-derived osteoclasts is the induction of apoptosis.
authors.affiliation: Department of Molecular Pharmacology and Biological Chemistry, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
authors.forename: K
authors.initials: K
authors.lastname: Igarashi
authors.forename: H
authors.initials: H
authors.lastname: Hirotani
authors.forename: J-T
authors.initials: JT
authors.lastname: Woo
authors.forename: P H
authors.initials: PH
authors.lastname: Stern
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis; D001854:Bone Marrow Cells / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D002352:Carrier Proteins / Q000378:metabolism; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D016572:Cyclosporine / Q000494:pharmacology*; D003524:Cyclosporins / Q000494:pharmacology; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D007527:Isoenzymes / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D010010:Osteoclasts / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D016559:Tacrolimus / Q000494:pharmacology*; D000071681:Tartrate-Resistant Acid Phosphatase
chemical_list: D002352:Carrier Proteins; D003524:Cyclosporins; D007166:Immunosuppressive Agents; D007527:Isoenzymes; D008562:Membrane Glycoproteins; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; C505687:Tnfrsf11a protein, mouse; C505689:Tnfsf11 protein, mouse; D016572:Cyclosporine; D000135:Acid Phosphatase; C000605511:Acp5 protein, mouse; D000071681:Tartrate-Resistant Acid Phosphatase; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases; C050025:cyclosporin H; D016559:Tacrolimus