Examination of the carboxylesterase phenotype in human liver.
Examination of the carboxylesterase phenotype in human liver.
复制标题
DOI：
10.1016/j.abb.2012.04.010
复制
发表时间：
2012-06-01
影响因子：
3.9
通讯作者：
Xie, Shuqi
中科院分区：
文献类型：
--
作者：
Ross, Matthew K.;Borazjani, Abdolsamad;Wang, Ran;Crow, J. Allen;Xie, Shuqi
羧酸酯酶（CES）代谢酯。两种CES亚型在人类肝脏中表达（CES1和CES2），肝脏提取物被用于反应表型研究，以辨别个体间的代谢差异。我们验证了一个假设，即个体的CES表型可以通过询问肝脏中天然CES1和CES2活性的报告底物/探针和免疫印迹方法来表征。我们获得了25个肝脏，发现CES1是主要的水解酶。此外，尽管CES1蛋白水平相似，但我们观察到生物除虫菊酯水解率在个体间存在很大差异（17倍），CES1代谢而CES2不代谢。氯氰菊酯水解率与CES1蛋白水平无关。相比之下，由CES2代谢而非CES1代谢的普鲁卡因水解率差异要小得多（3倍）。使用基于活性的氟膦酸盐探针（fp -生物素）与活性丝氨酸水解酶共价反应，CES1蛋白是肝脏中最活跃的酶。最后，利用生物正交探针和click化学方法，估计CES1和ces2在培养的HepG2细胞中的半衰期为96小时。CES1活性差异的原因尚不清楚，但潜在因素将是重要的，因为几种羧酸酯药物和环境毒物都是由这种酶代谢的。
Carboxylesterases (CES) metabolize esters. Two CES isoforms are expressed in human liver (CES1 and CES2) and liver extracts are used in reaction phenotyping studies to discern interindividual metabolic variation. We tested the hypothesis that an individual’s CES phenotype can be characterized by reporter substrates/probes that interrogate native CES1 and CES2 activities in liver and immunoblotting methods. We obtained 25 livers and found that CES1 is the main hydrolytic enzyme. Moreover, although CES1 protein levels were similar, we observed large interindividual variation in bioresmethrin hydrolysis rates (17-fold), a pyrethroid metabolized by CES1 but not CES2. Bioresmethrin hydrolysis rates did not correlate with CES1 protein levels. In contrast, procaine hydrolysis rates, a drug metabolized by CES2 but not CES1, were much less variant (3-fold). Using activity-based fluorophosphonate probes (FP-biotin), which covalently reacts with active serine hydrolases, CES1 protein was the most active enzyme in the livers. Finally, using bioorthogonal probes and click chemistry methodology, the half-life of CES 1 and 2 in cultured HepG2 cells was estimated at 96 h. The cause of the differential CES1 activities is unknown, but the underlying factors will be important to understand because several carboxylic acid ester drugs and environmental toxicants are metabolized by this enzyme.
登录
查看更多内容
影响因子：
3.9
作者：
Godin, Stephen J.;Scollon, Edward J.;Ross, Matthew K.
通讯作者：
Ross, Matthew K.
影响因子：
5.6
作者：
Fleming, CD;Bencharit, S;Redinbo, MR
通讯作者：
Redinbo, MR
影响因子：
7.3
作者：
Hyatt, JL;Stacy, V;Potter, PM
通讯作者：
Potter, PM
影响因子：
3.9
作者：
Fisher, Craig D.;Lickteig, Andrew J.;Cherrington, Nathan J.
通讯作者：
Cherrington, Nathan J.
影响因子：
4.4
作者：
Marsh, S;Xiao, M;McLeod, HL
通讯作者：
McLeod, HL