title: Estrogen specifically stimulates expression and production of osteoprotegerin from rheumatoid synovial fibroblasts.
abstract: We studied the effects of estrogen on human fibroblast-like synovial cells in rheumatoid arthritis (RA-FLS) focusing on receptor activator of NF-kappaB ligand (RANKL) and its decoy receptor osteoprotegerin (OPG), the osteoclast formation and function regulators that have a substantial role in bone erosion of RA. Estrogen influences osteoporosis and the onset of RA clinically. The cellular responses of RA-FLS to estrogen are initiated via two high-affinity estrogen receptors (ERs). Culture of RA-FLS in the presence of 10(-6) M 17beta-estradiol (E2) increased expression of estrogen receptor (ER)-alpha, but not ER-beta. OPG mRNA expression was significantly increased, whereas RANKL mRNA was unaffected. E2 treatment also significantly increased the amount of OPG released in the culture supernatant. The increase of OPG and ER-alpha was specifically antagonized by the pure estrogen antagonist ICI 182780. Tamoxifen, a selective ER moderator, did not increase OPG. The results indicate that estrogen stimulates secretion of OPG from RA-FLS by acting on ER-alpha, which likely prevents bone erosion in RA.
authors.affiliation: Department of Orthopaedic Surgery, Kobe University, Graduate School of Medicine, Kobe 650-0017, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Mitani
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Miura
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Saura
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kitagawa
authors.forename: Taihei
authors.initials: T
authors.lastname: Fukuyama
authors.forename: Akira
authors.initials: A
authors.lastname: Hashiramoto
authors.forename: Shunichi
authors.initials: S
authors.lastname: Shiozawa
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kurosaka
authors.forename: Shinichi
authors.initials: S
authors.lastname: Yoshiya
mesh_terms: D001172:Arthritis, Rheumatoid / Q000378:metabolism*; D002352:Carrier Proteins / Q000096:biosynthesis; D002478:Cells, Cultured; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology*; D020847:Estrogen Receptor Modulators / Q000494:pharmacology; D047628:Estrogen Receptor alpha / Q000096:biosynthesis; D047629:Estrogen Receptor beta / Q000096:biosynthesis; D004967:Estrogens / Q000494:pharmacology*; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism; D000077267:Fulvestrant; D006023:Glycoproteins / Q000096:biosynthesis*; D006801:Humans; D008562:Membrane Glycoproteins / Q000096:biosynthesis; D053244:Osteoprotegerin; D053245:RANK Ligand; D012333:RNA, Messenger / Q000096:biosynthesis; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear / Q000096:biosynthesis*; D018124:Receptors, Tumor Necrosis Factor / Q000096:biosynthesis*; D013583:Synovial Membrane / Q000378:metabolism*; D013629:Tamoxifen / Q000494:pharmacology; D015854:Up-Regulation
chemical_list: D002352:Carrier Proteins; D020847:Estrogen Receptor Modulators; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D004967:Estrogens; D006023:Glycoproteins; D008562:Membrane Glycoproteins; D053244:Osteoprotegerin; D053245:RANK Ligand; D012333:RNA, Messenger; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; C505686:TNFRSF11A protein, human; C506030:TNFRSF11B protein, human; C505688:TNFSF11 protein, human; D013629:Tamoxifen; D000077267:Fulvestrant; D004958:Estradiol