title: Neutral buoyancy and sleep-deprived serum factors alter expression of cytokines regulating osteogenesis.
abstract: We examined expression of genes associated with cytokine production, and genes implicated in regulating bone metabolism, in bone stromal and osteoblast cells incubated under standard ground conditions and under conditions of neutral buoyancy, and in the presence/absence of serum from normal or sleep-deprived mice. We observed a clear interaction between these two conditions (exposure to neutral buoyancy and serum stimulation) in promoting enhanced osteoclastogenesis. Both conditions independently altered expression of a number of cytokines implicated in the regulation of bone metabolism. However, using stromal cells from IL-1 and TNFx cytokine(r) KO mice, we concluded that the increased bone loss under microgravity conditions was not primarily cytokine mediated.
authors.affiliation: Transplant Research Division, Toronto General Hospital, Toronto, Ont., Canada. reg.gorczynski@utoronto.ca
authors.forename: Reginald M
authors.initials: RM
authors.lastname: Gorczynski
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Gorczynski
authors.forename: Laura Y
authors.initials: LY
authors.lastname: Gorczynski
authors.forename: Jiang
authors.initials: J
authors.lastname: Hu
authors.forename: Jin
authors.initials: J
authors.lastname: Lu
authors.forename: Justin
authors.initials: J
authors.lastname: Manuel
authors.forename: Lydia
authors.initials: L
authors.lastname: Lee
mesh_terms: D016475:3T3 Cells; D000818:Animals; D018488:Bone Demineralization, Pathologic / Q000235:genetics / Q000503:physiopathology*; D001842:Bone and Bones / Q000378:metabolism*; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000235:genetics; D002478:Cells, Cultured; D016207:Cytokines / Q000032:analysis / Q000096:biosynthesis / Q000235:genetics; D015870:Gene Expression; D006023:Glycoproteins / Q000096:biosynthesis* / Q000235:genetics; D007375:Interleukin-1 / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010006:Osteoblasts / Q000378:metabolism; D053244:Osteoprotegerin; D016133:Polymerase Chain Reaction; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear / Q000096:biosynthesis* / Q000235:genetics; D018124:Receptors, Tumor Necrosis Factor / Q000096:biosynthesis / Q000235:genetics; D012892:Sleep Deprivation / Q000503:physiopathology*; D017154:Stromal Cells / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000235:genetics; D018474:Weightlessness Simulation
chemical_list: D002352:Carrier Proteins; D016207:Cytokines; D006023:Glycoproteins; D007375:Interleukin-1; D008562:Membrane Glycoproteins; D053244:Osteoprotegerin; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; C505687:Tnfrsf11a protein, mouse; C506031:Tnfrsf11b protein, mouse; C505689:Tnfsf11 protein, mouse; D014409:Tumor Necrosis Factor-alpha