Kinouchi Hiroki, Matsuyama Keigo, Kitagawa Hiroshi, Kamimori Hiroshi
Pharmaceutical Research Division, Shionogi & Co., Toyonaka, Osaka 561-0825, Japan; Department of Biochemistry, Kobe Pharmaceutical University, Higashinada-ku, Kobe 658-8558, Japan.
Pharmaceutical Research Division, Shionogi & Co., Toyonaka, Osaka 561-0825, Japan.
Anal Biochem. 2016 Jan 1;492:43-8. doi: 10.1016/j.ab.2015.09.004. Epub 2015 Sep 15.
We developed a surface plasmon resonance (SPR) assay to estimate the competitive inhibition by pharmaceuticals for thyroxine (T4) binding to thyroid hormone transport proteins, transthyretin (TTR) and thyroxine binding globulin (TBG). In this SPR assay, the competitive inhibition of pharmaceuticals for introducing T4 into immobilized TTR or TBG on the sensor chip can be estimated using a running buffer containing pharmaceuticals. The SPR assay showed reproducible immobilization of TTR and TBG, and the kinetic binding parameters of T4 to TTR or TBG were estimated. The equilibrium dissociation constants of TTR or TBG measured by SPR did not clearly differ from data reported for other binding assays. To estimate the competitive inhibition of tetraiodothyroacetic acid, diclofenac, genistein, ibuprofen, carbamazepine, and furosemide, reported to be competitive or noncompetitive pharmaceuticals for T4 binding to TTR or TBG, their 50% inhibition concentrations (IC50) (or 80% inhibition concentration, IC80) were calculated from the change of T4 responses in sensorgrams obtained with various concentrations of the pharmaceuticals. Our SPR method should be a useful tool for predicting the potential of thyroid toxicity of pharmaceuticals by evaluating the competitive inhibition of T4 binding to thyroid hormone binding proteins, TTR and TBG.
我们开发了一种表面等离子体共振（SPR）分析方法，以评估药物对甲状腺素（T4）与甲状腺激素转运蛋白甲状腺素结合球蛋白（TTR）和甲状腺素结合球蛋白（TBG）结合的竞争性抑制作用。在这种SPR分析中，可以使用含有药物的运行缓冲液来评估药物对将T4引入传感器芯片上固定化的TTR或TBG的竞争性抑制作用。SPR分析显示TTR和TBG的固定具有可重复性，并估计了T4与TTR或TBG的动力学结合参数。通过SPR测量的TTR或TBG的平衡解离常数与其他结合分析报道的数据没有明显差异。为了评估四碘甲状腺乙酸、双氯芬酸、染料木黄酮、布洛芬、卡马西平和呋塞米对T4与TTR或TBG结合的竞争性抑制作用（据报道这些药物对T4与TTR或TBG的结合具有竞争性或非竞争性），根据在不同浓度药物下获得的传感图中T4响应的变化计算了它们的50%抑制浓度（IC50）（或80%抑制浓度，IC80）。我们的SPR方法应该是一种有用的工具，通过评估药物对T4与甲状腺激素结合蛋白TTR和TBG结合的竞争性抑制作用来预测药物甲状腺毒性的可能性。
