Triiodothyronine stimulates cystatin C production in bone cells

• Published in: Biochemical and biophysical research communications 2012-03, Vol.419 (2), p.425-430
• Main Authors: Schmid, Christoph, Ghirlanda-Keller, Claudia, Zwimpfer, Cornelia, Zoidis, Evangelos
• Format: Article
• Language: English
• Subjects: Alkaline Phosphatase - biosynthesis; Animals; Cells, Cultured; Cystatin C; Cystatin C - biosynthesis; Deoxyglucose - analogs & derivatives; Deoxyglucose - metabolism; Dexamethasone; Dexamethasone - pharmacology; Glucose Transporter Type 3 - biosynthesis; Osteoblast; Osteoblasts - drug effects; Osteoblasts - metabolism; Rats; RNA, Messenger - biosynthesis; Triiodothyronine; Triiodothyronine - pharmacology
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2012.02.040

► Thyroid hormone dependency of cystatin C serum concentration in vivo. ► Triiodothyronine increases cystatin C mRNA expression in osteoblasts in vitro. ► Triiodothyronine increases cystatin C protein accumulation in culture media. Thyroid hormones increase cystatin C levels in vivo. To study whether 3,3′,5-triiodo-l-thyronine (T3) stimulates the production of cystatin C in vitro, we used a T3-responsive osteoblastic cell line (PyMS) which can be kept in serum-free culture. We compared the effects of T3 on cystatin C mRNA expression (by Northern) and on protein release (by Western and ELISA) with those of dexamethasone (dex). Triiodothyronine increased cystatin C mRNA expression and cystatin C accumulation in culture media in a dose- and time-dependent manner, 1.5-fold at 1nmol/l after 4d; dex (100nmol/l) was more potent and increased cystatin C accumulation 3-fold after 4d. Triiodothyronine but not dex stimulated glucose uptake. Our in vitro findings explain in vivo observations. Triiodothyronine-induced increase in the production of cystatin C may be related to an increased cell metabolism and proteolysis control demand.