title: Triiodothyronine (T3) does not induce Rankl expression in rat Ros 17/2.8 cells.
abstract: Osteoclastogenesis may be regulated via activation of the RANK/RANKL (receptor activator of nuclear factor-kappa B/receptor activator of nuclear factor-kappa B ligand) system, which is mediated by osteoblasts. However, the bone loss mechanism induced by T3 (triiodothyronine) is still controversial. In this study, osteoblastic lineage rat cells (ROS 17/2.8) were treated with T3 (10(-8) M, 10(-9) M, and 10(-10) M), and RANKL mRNA (messenger RNA) expression was measured by semiquantitative RT-PCR. Our results show that T3 concentrations used did not significantly enhance RANKL expression compared to controls without hormone treatment. This data suggests that other mechanisms, unrelated to the RANK/RANKL system, might be to activate osteoclast differentiation in these cells.
authors.affiliation: Department of Medical Clinical of Botucatu School of Medicine, Sao Paulo State University, Botucatu, SP, Brazil. saraivapat@yahoo.com.br
authors.forename: Patrícia P
authors.initials: PP
authors.lastname: Saraiva
authors.forename: Silvania S
authors.initials: SS
authors.lastname: Teixeira
authors.forename: Carlos Roberto
authors.initials: CR
authors.lastname: Padovani
authors.forename: Célia Regina
authors.initials: CR
authors.lastname: Nogueira
mesh_terms: D000818:Animals; D001862:Bone Resorption / Q000188:drug therapy* / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D004587:Electrophoresis, Agar Gel; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects*; D010010:Osteoclasts / Q000378:metabolism; D053245:RANK Ligand / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D011988:Receptors, Thyroid Hormone / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014284:Triiodothyronine / Q000494:pharmacology*
chemical_list: D053245:RANK Ligand; D012333:RNA, Messenger; D011988:Receptors, Thyroid Hormone; D014284:Triiodothyronine