title: Estrogen deficiency induces bone loss by enhancing T-cell production of TNF-alpha.
abstract: Estrogen deficiency induces bone loss by upregulating osteoclastogenesis by mechanisms not completely defined. We found that ovariectomy-enhanced T-cell production of TNF-alpha, which, acting through the TNF-alpha receptor p55, augments macrophage colony-stimulating factor-induced (M-CSF-induced) and RANKL-induced osteoclastogenesis. Ovariectomy failed to induce bone loss, stimulate bone resorption, or increase M-CSF- and RANKL-dependent osteoclastogenesis in T-cell deficient mice, establishing T cells as essential mediators of the bone-wasting effects of estrogen deficiency in vivo. These findings demonstrate that the ability of estrogen to target T cells, suppressing their production of TNF-alpha, is a key mechanism by which estrogen prevents osteoclastic bone resorption and bone loss.
authors.affiliation: Division of Bone and Mineral Diseases, Washington University School of Medicine and Barnes-Jewish Hospital, St. Louis, Missouri 63110, USA.
authors.forename: S
authors.initials: S
authors.lastname: Cenci
authors.forename: M N
authors.initials: MN
authors.lastname: Weitzmann
authors.forename: C
authors.initials: C
authors.lastname: Roggia
authors.forename: N
authors.initials: N
authors.lastname: Namba
authors.forename: D
authors.initials: D
authors.lastname: Novack
authors.forename: J
authors.initials: J
authors.lastname: Woodring
authors.forename: R
authors.initials: R
authors.lastname: Pacifici
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism*; D001862:Bone Resorption / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism*; D002478:Cells, Cultured; D004967:Estrogens / Q000502:physiology*; D016173:Macrophage Colony-Stimulating Factor / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008819:Mice, Nude; D010010:Osteoclasts / Q000502:physiology; D010052:Ovariectomy; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018124:Receptors, Tumor Necrosis Factor / Q000235:genetics / Q000378:metabolism*; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; D013601:T-Lymphocytes / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
chemical_list: D015703:Antigens, CD; D002352:Carrier Proteins; D004967:Estrogens; D008562:Membrane Glycoproteins; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018124:Receptors, Tumor Necrosis Factor; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; C505687:Tnfrsf11a protein, mouse; C505689:Tnfsf11 protein, mouse; D014409:Tumor Necrosis Factor-alpha; D016173:Macrophage Colony-Stimulating Factor