title: Effect of oestradiol on cytokine production in immortalized human marrow stromal cell lines.
abstract: Oestrogen deficiency enhances bone osteoclastogenesis and bone resorption. Evidence of cooperation between stromal cells and osteoclast precursors in mice suggests that oestradiol acts by regulating cytokine release from stromal cells. Bone marrow stroma contains multipotent progenitors that give rise to many mesenchymal lineages, including osteoblasts that may regulate osteoclast differentiation. We immortalized and characterized six human bone marrow stromal cell lines (presence of Stro1, secretion of alkaline phosphatase, osteocalcin, formation of lipid droplets, and presence of alpha and beta oestrogen receptors). The response of cytokines to oestradiol was then evaluated in vitro, as were the phorbol myristate acetate (PMA)-stimulated cytokine levels. Cells had the characteristics of undifferentiated stromal cells (Stro1+, RANK-L+), and expressed alpha-oestrogen receptors. The osteoblast phenotype (amounts of alkaline phosphatase and osteocalcin) was weak and there was a poor capacity to differentiate into adipocytes. These cell lines did not respond to oestradiol by producing interleukin 6 (IL-6), IL-1 or tumour necrosis factor alpha (TNF-alpha) either constitutively or after stimulation with PMA. Moreover, RANK-L and osteoprotegerin expressions were not regulated by oestradiol in vitro. Thus, modulation of these cytokines by stromal cells do not appear to be the mechanism by which oestradiol regulates bone resorption in humans.
authors.affiliation: INSERM U349, Centre Viggo Petersen and Laboratoire de Biologie Endocrinienne, Lariboisière Hospital, Paris, France.
authors.forename: A C
authors.initials: AC
authors.lastname: Ramalho
authors.forename: A
authors.initials: A
authors.lastname: Jullienne
authors.forename: P
authors.initials: P
authors.lastname: Couttet
authors.forename: A M
authors.initials: AM
authors.lastname: Graulet
authors.forename: C
authors.initials: C
authors.lastname: Morieux
authors.forename: M C
authors.initials: MC
authors.lastname: de Vernejoul
authors.forename: M E
authors.initials: ME
authors.lastname: Cohen-Solal
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000187:drug effects* / Q000276:immunology*; D002352:Carrier Proteins / Q000235:genetics; D002460:Cell Line; D016207:Cytokines / Q000096:biosynthesis*; D004958:Estradiol / Q000494:pharmacology*; D047628:Estrogen Receptor alpha; D015870:Gene Expression / Q000187:drug effects; D006023:Glycoproteins / Q000235:genetics; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis; D015850:Interleukin-6 / Q000096:biosynthesis; D008562:Membrane Glycoproteins / Q000235:genetics; D051379:Mice; D053244:Osteoprotegerin; D053245:RANK Ligand; D012313:RNA / Q000235:genetics / Q000378:metabolism; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics; D011960:Receptors, Estrogen / Q000235:genetics; D018124:Receptors, Tumor Necrosis Factor; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D002352:Carrier Proteins; D016207:Cytokines; D047628:Estrogen Receptor alpha; D006023:Glycoproteins; D007375:Interleukin-1; D015850:Interleukin-6; D008562:Membrane Glycoproteins; D053244:Osteoprotegerin; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear; D011960:Receptors, Estrogen; D018124:Receptors, Tumor Necrosis Factor; C505686:TNFRSF11A protein, human; C506030:TNFRSF11B protein, human; C505688:TNFSF11 protein, human; C505687:Tnfrsf11a protein, mouse; C506031:Tnfrsf11b protein, mouse; C505689:Tnfsf11 protein, mouse; D014409:Tumor Necrosis Factor-alpha; D004958:Estradiol; D012313:RNA; D013755:Tetradecanoylphorbol Acetate