title: Dexamethasone regulates IL-1 beta and TNF-alpha-induced interleukin-8 production in human bone marrow stromal and osteoblast-like cells.
abstract: We have investigated both constitutive- and cytokine-induced secretion of interleukin-8 (IL-8) and its regulation by dexamethasone and 17 beta-estradiol in normal human bone marrow stromal (HBMS), osteoblast-like cells (hOB), and osteosarcoma MG-63 cells. Although HBMS cells secrete low levels of IL-8 constitutively, treatment with IL-1 beta and tumor necrosis factor-alpha (TNF-alpha) induced IL-8 secretion. Their effects were synergistic but IL-8 production was not affected by 17 beta-estradiol. Human osteosarcoma MG-63 cells also secreted low levels of IL-8 constitutively; the production was induced by IL-1 beta and TNF-alpha and was also not affected by 17 beta-estradiol. The magnitude of the response to cytokine stimulation of IL-8 in MG-63 cells was much lower than that of HBMS and hOB cells, indicating differences in response in normal and osteoblastic osteosarcoma cells. Dexamethasone (10(-7) M) significantly inhibited IL-1 beta plus TNF-alpha stimulated IL-8 production in HBMS, MG-63, and hOB cells. The accumulated results demonstrate that IL-8 is secreted by HBMS, MG-63, and hOB cells, suggesting that IL-8 may play a role in the regulation of bone cell function. These data also emphasize the importance of glucocorticoids in controlling cytokine secretion in HBMS, hOB, and MG-63 cells.
authors.affiliation: Division of Bone and Mineral Diseases, Jewish Hospital of St. Louis, Washington University Medical Center, Missouri 63110.
authors.forename: L R
authors.initials: LR
authors.lastname: Chaudhary
authors.forename: L V
authors.initials: LV
authors.lastname: Avioli
mesh_terms: D001853:Bone Marrow / Q000187:drug effects / Q000378:metabolism*; D001854:Bone Marrow Cells; D001859:Bone Neoplasms / Q000378:metabolism; D002478:Cells, Cultured; D017077:Culture Media, Conditioned; D003907:Dexamethasone / Q000494:pharmacology*; D004357:Drug Synergism; D004797:Enzyme-Linked Immunosorbent Assay; D004958:Estradiol / Q000494:pharmacology*; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D016209:Interleukin-8 / Q000096:biosynthesis*; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D012516:Osteosarcoma / Q000378:metabolism; D012272:Ribs; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D017077:Culture Media, Conditioned; D007375:Interleukin-1; D016209:Interleukin-8; D014409:Tumor Necrosis Factor-alpha; D004958:Estradiol; D003907:Dexamethasone