Kurokawa Takaya, Fukami Tatsuki, Yoshida Tomohiro, Nakajima Miki
Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kakuma-machi, Kanazawa, Japan.
Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kakuma-machi, Kanazawa, Japan
Drug Metab Dispos. 2016 Mar;44(3):409-16. doi: 10.1124/dmd.115.068221. Epub 2015 Dec 30.
Prasugrel, a thienopyridine anti-platelet agent, is pharmacologically activated by hydrolysis and hydroxylation. It is efficiently hydrolyzed in the intestine after oral administration, and the enzyme responsible for the hydrolysis in humans was demonstrated to be carboxylesterase (CES)2. Prasugrel hydrolase activity is detected in dog intestines, where CES enzymes are absent; therefore, this prompted us to investigate the involvement of an enzyme(s) other than CES. Human arylacetamide deacetylase (AADAC) is highly expressed in the small intestine, catalyzing the hydrolysis of several clinical drugs containing small acyl moieties. In the present study, we investigated whether AADAC catalyzes prasugrel hydrolysis. Recombinant human AADAC was shown to catalyze prasugrel hydrolysis with a CLint value of 50.0 ± 1.2 ml/min/mg protein with a similar Km value to human intestinal and liver microsomes, whereas the CLint values of human CES1 and CES2 were 4.6 ± 0.1 and 6.6 ± 0.3 ml/min/mg protein, respectively. Inhibition studies using various chemical inhibitors and the relative activity factor approach suggested that the contribution of AADAC to prasugrel hydrolysis in human intestine is comparable to that of CES2. In dog intestine, the expression of AADAC, but not CES1 and CES2, was confirmed by measuring the marker hydrolase activities of each human esterase. The similar Km values and inhibition profiles between recombinant dog AADAC and small intestinal microsomes suggest that AADAC is a major enzyme responsible for prasugrel hydrolysis in dog intestine. Collectively, we found that AADAC largely contributes to prasugrel hydrolysis in both human and dog intestine.
普拉格雷是一种噻吩并吡啶类抗血小板药物，通过水解和羟基化进行药理活化。口服给药后，它在肠道中有效水解，并且已证明负责人类水解的酶是羧酸酯酶（CES）2。在不存在CES酶的犬肠道中检测到普拉格雷水解酶活性；因此，这促使我们研究除CES之外的其他酶的作用。人芳基乙酰胺脱乙酰酶（AADAC）在小肠中高度表达，催化几种含有小酰基部分的临床药物的水解。在本研究中，我们研究了AADAC是否催化普拉格雷水解。重组人AADAC被证明可催化普拉格雷水解，其内在清除率（CLint）值为50.0±1.2 ml/min/mg蛋白，与人类肠道和肝脏微粒体的Km值相似，而人CES1和CES2的CLint值分别为4.6±0.1和6.6±0.3 ml/min/mg蛋白。使用各种化学抑制剂的抑制研究和相对活性因子方法表明，AADAC对人肠道中普拉格雷水解的贡献与CES2相当。在犬肠道中，通过测量每个人类酯酶的标记水解酶活性，证实了AADAC的表达，而CES1和CES2未表达。重组犬AADAC和小肠微粒体之间相似的Km值和抑制谱表明，AADAC是犬肠道中负责普拉格雷水解的主要酶。总体而言，我们发现AADAC在人和犬肠道中对普拉格雷水解都有很大贡献。
