title: Triiodothyronine stimulates glucose transport in bone cells.
abstract: Thyroid hormones increase energy expenditure and bone turnover in vivo. To study whether 3,3',5-triiodo-l-thyronine (T₃) stimulates the uptake of glucose in osteoblastic cells, PyMS (a cell line derived from rat bone) cells were kept in serum-free culture medium and treated with T₃. We measured [1-¹⁴C]-2-deoxy-D: -glucose (2DG) uptake and looked for expression of the high-affinity glucose transporters GLUT1 and GLUT3 by northern and western analysis. T₃ did not influence the cell number but slightly (1.3-fold) increased the protein content of the cell cultures. 2DG uptake was low in serum-deprived cell cultures and was increased by T₃ (up to 2.5-fold at 1 nmol l⁻¹ after 4 days) in a dose- and time-dependent manner. Triiodothyronine at 1 nmol l⁻¹ increased GLUT1 and GLUT3 abundance in membranes. Therefore, increased glucose uptake induced by T₃ in osteoblasts may be mediated by the known high-affinity glucose transporters GLUT1 and GLUT3.
authors.affiliation: Department of Nutritional Physiology and Feeding, Faculty of Animal Science and Aquaculture, Agricultural University of Athens, 118 55, Athens, Greece. ezoidis@aua.gr
authors.forename: Evangelos
authors.initials: E
authors.lastname: Zoidis
authors.forename: Claudia
authors.initials: C
authors.lastname: Ghirlanda-Keller
authors.forename: Christoph
authors.initials: C
authors.lastname: Schmid
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002117:Calcitriol / Q000378:metabolism; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D016895:Culture Media, Serum-Free / Q000378:metabolism; D003847:Deoxyglucose / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D051272:Glucose Transporter Type 1 / Q000235:genetics / Q000378:metabolism*; D051274:Glucose Transporter Type 3 / Q000235:genetics / Q000378:metabolism*; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D007700:Kinetics; D010006:Osteoblasts / Q000187:drug effects / Q000378:metabolism*; D010281:Parathyroid Hormone / Q000494:pharmacology; D010446:Peptide Fragments / Q000494:pharmacology; D014176:Protein Biosynthesis / Q000187:drug effects; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011994:Recombinant Proteins / Q000378:metabolism; D014284:Triiodothyronine / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D016895:Culture Media, Serum-Free; D051272:Glucose Transporter Type 1; D051274:Glucose Transporter Type 3; D010281:Parathyroid Hormone; D010446:Peptide Fragments; D012333:RNA, Messenger; D011994:Recombinant Proteins; C495679:Slc2a1 protein, rat; C495690:Slc2a3 protein, rat; D014284:Triiodothyronine; C025076:parathyroid hormone (1-34), bovine; D007334:Insulin-Like Growth Factor I; D003847:Deoxyglucose; D002117:Calcitriol; D005947:Glucose