Cao Wei, Cao Ya-jie, Hu Zhe-yi, Yu Qi, Wang Li-qing, Tan Gui-shan, Cheng Ze-neng
School of Pharmaceutical Sciences, Central South University, Changsha 410013, China.
Zhong Nan Da Xue Xue Bao Yi Xue Ban. 2006 Dec;31(6):858-61.
To explore the inhibitive effects of 1,3,8-trihydroxy-5-methoxyxanthone (TMX) on cytochrome P450s (CYP450s) in human liver microsomes.
Probe drugs were incubated with and without adding TMX to determine the changes of enzyme activities. The concentration ratio of metabolites to probe drugs was used to present enzyme activities. Concentrations of the probe drugs and their metabolites in the incubated mixture were detected by high performance liquid chromatography.
The variations (mean, 95%CI) of the activities of CYP1A2, CYP2C9, CYP2C19, CYP2E1 and CYP3A4 were 2.95 x 10(-3) (2.03 x 10(-3), 3.88 x 10(-3)), 3.14 x 10(-2) (1.87 x 10(-2), 4.42 x 10(-2)), 2.27 x 10(-3) (-1.4 x 10(-2),1.81 x 10(-2)), 7.72 x 10(-2) (-0.83 x 10(-2), 0.2374), and -0.2548 (-2.9802, 2.4707), respectively. The activities of CYP1A2 and CYP2C9 were significantly reduced in the present of TMX.
TMX (10 micromol/L) has significant inhibitive effect on the activities of CYP1A2 and CYP2C9, but no significant inhibitive effect on the activities of CYP2C19, CYP2E1 and CYP3A4.
探讨1,3,8 - 三羟基 - 5 - 甲氧基呫吨酮（TMX）对人肝微粒体细胞色素P450酶（CYP450s）的抑制作用。
将探针药物分别在添加和不添加TMX的情况下进行孵育，以确定酶活性的变化。代谢产物与探针药物的浓度比用于表示酶活性。通过高效液相色谱法检测孵育混合物中探针药物及其代谢产物的浓度。
CYP1A2、CYP2C9、CYP2C19、CYP2E1和CYP3A4酶活性的变化（平均值，95%置信区间）分别为2.95×10⁻³（2.03×10⁻³，3.88×10⁻³）、3.14×10⁻²（1.87×10⁻²，4.42×10⁻²）、2.27×10⁻³（ - 1.4×10⁻²，1.81×10⁻²）、7.72×10⁻²（ - 0.83×10⁻²，0.2374）和 - 0.2548（ - 2.9802，2.4707）。在TMX存在的情况下，CYP1A2和CYP2C9的活性显著降低。
TMX（10微摩尔/升）对CYP1A2和CYP2C9的活性有显著抑制作用，但对CYP2C19、CYP2E1和CYP3A4的活性无显著抑制作用。
