Vrba Jiri, Papouskova Barbora, Pyszkova Michaela, Zatloukalova Martina, Lemr Karel, Ulrichova Jitka, Vacek Jan
Department of Medical Chemistry and Biochemistry, Faculty of Medicine and Dentistry, Palacky University, Hnevotinska 3, Olomouc 77515, Czech Republic.
Regional Centre of Advanced Technologies and Materials, Department of Analytical Chemistry, Faculty of Science, Palacky University, 17, listopadu 12, Olomouc 77146, Czech Republic.
J Pharm Biomed Anal. 2015 Jan;102:193-8. doi: 10.1016/j.jpba.2014.09.015. Epub 2014 Sep 19.
In this study, we developed a new liquid chromatography-mass spectrometry (LC-MS) method for analysis of the protoberberine alkaloid palmatine and its metabolites with separation performed on a cyanopropyl-modified stationary phase. Palmatine (10 μM) was metabolized using suspensions of human hepatocytes and human recombinant cytochrome P450 (CYP) enzymes. Our analyses using electrospray ionization-quadrupole time-of-flight mass spectrometry revealed that palmatine was relatively resistant to the metabolic activity of human hepatocytes and recombinant CYP enzymes. However, we found that the biotransformation of palmatine in human hepatocytes included O-demethylation or hydroxylation, and that the product of palmatine demethylation was conjugated by glucuronidation or sulfation. Moreover, we found that human recombinant CYP2D6 and, to a lesser extent, CYP1A2 can mediate O-demethylation of palmatine. These results provide fundamental insights into the biotransformation of palmatine in human in vitro models and, together with the LC-MS method, can be applied for further studies on the biotransformation of palmatine and other protoberberine alkaloids.
在本研究中，我们开发了一种新的液相色谱 - 质谱联用（LC-MS）方法，用于分析原小檗碱类生物碱巴马汀及其代谢产物，分离在氰丙基改性固定相上进行。使用人肝细胞和人重组细胞色素P450（CYP）酶悬浮液对巴马汀（10μM）进行代谢。我们使用电喷雾电离 - 四极杆飞行时间质谱的分析表明，巴马汀对人肝细胞和重组CYP酶的代谢活性具有相对抗性。然而，我们发现巴马汀在人肝细胞中的生物转化包括O-去甲基化或羟基化，并且巴马汀去甲基化产物通过葡萄糖醛酸化或硫酸化进行缀合。此外，我们发现人重组CYP2D6以及程度较轻的CYP1A2可以介导巴马汀的O-去甲基化。这些结果为巴马汀在人体外模型中的生物转化提供了基本见解，并且与LC-MS方法一起，可用于进一步研究巴马汀和其他原小檗碱类生物碱的生物转化。
