Division of Endocrinology and Diabetology, University Hospital of Zurich, CH-8091 Zurich, Switzerland.
Biochem Biophys Res Commun. 2012 Mar 9;419(2):425-30. doi: 10.1016/j.bbrc.2012.02.040. Epub 2012 Feb 14.
Thyroid hormones increase cystatin C levels in vivo. To study whether 3,3',5-triiodo-l-thyronine (T(3)) stimulates the production of cystatin C in vitro, we used a T(3)-responsive osteoblastic cell line (PyMS) which can be kept in serum-free culture. We compared the effects of T(3) 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 1 nmol/l after 4d; dex (100 nmol/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.
甲状腺激素会增加体内胱抑素 C 水平。为了研究 3,3',5-三碘甲腺原氨酸（T3）是否能刺激胱抑素 C 的体外产生，我们使用了一种对 T3 有反应的成骨细胞系（PyMS），该细胞系可以在无血清培养中保存。我们将 T3 对胱抑素 C mRNA 表达（通过 Northern 印迹法）和蛋白释放（通过 Western 印迹法和 ELISA）的影响与地塞米松（dex）的影响进行了比较。三碘甲状腺原氨酸以剂量和时间依赖的方式增加胱抑素 C mRNA 表达和培养上清液中胱抑素 C 的积累，4d 后 1nmol/L 时增加 1.5 倍；地塞米松（100nmol/L）作用更强，4d 后胱抑素 C 积累增加 3 倍。三碘甲状腺原氨酸而非地塞米松刺激葡萄糖摄取。我们的体外发现解释了体内观察结果。三碘甲状腺原氨酸诱导的胱抑素 C 产生增加可能与细胞代谢和蛋白水解控制需求的增加有关。
