Cvilink Viktor, Szotáková Barbora, Vokrál Ivan, Bártíková Hana, Lamka Jirí, Skálová Lenka
Department of Biochemical Sciences, Faculty of Pharmacy, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
Rapid Commun Mass Spectrom. 2009 Sep;23(17):2679-84. doi: 10.1002/rcm.4170.
With further use of chemical agents in the control of parasitic infections, an increased number of drug resistance occurrences to antiparasitic drugs has been reported. Induction of enzymes responsible for detoxification of given drugs can contribute to drug resistance development in a parasitic organism. The identification of formed metabolites allows the characterization of the enzymes participating in biotransformation and possibly in drug resistance development. The objective of our work was to find and identify phase I and phase II metabolites of the anthelminthic drugs albendazole, flubendazole and mebendazole formed in ex vivo incubations by the parasitic helminth Dicrocoelium dendriticum, a parasite of ruminants and other grazing animals, using liquid chromatography/mass spectrometric (LC/MS) techniques. In the ex vivo study, approximately 50 living D. dendriticum adults were incubated in 5 mL RPMI-1640 medium in the presence of 10.0 micromol L(-1) benzimidazole drug (5% CO(2), 38 degrees C) for 24 h. The bodies of the parasite were then removed from the medium. After homogenization of parasites, both parasite homogenates and medium from the incubation were separately extracted using solid-phase extraction. The extracts were analyzed using LC/MS with electrospray ionization. The results showed that D. dendriticum enzymatic systems are capable of phase I oxidation and reduction as well as phase II conjugation reactions. Detected phase I metabolites comprised albendazole sulfoxide, reduced flubendazole and reduced mebendazole. As for phase II metabolites, methyl derivatives of both reduced flubendazole and reduced mebendazole were observed.
随着化学药剂在寄生虫感染控制中的进一步应用，据报道对抗寄生虫药物产生耐药性的情况越来越多。诱导负责特定药物解毒的酶可能会导致寄生虫产生耐药性。鉴定形成的代谢产物有助于表征参与生物转化以及可能参与耐药性发展的酶。我们研究的目的是利用液相色谱/质谱（LC/MS）技术，寻找并鉴定反刍动物和其他食草动物的寄生虫——枝双腔吸虫（Dicrocoelium dendriticum）在体外孵育过程中形成的驱虫药阿苯达唑、氟苯达唑和甲苯达唑的I相和II相代谢产物。在体外研究中，将约50条活的成年枝双腔吸虫置于含有10.0微摩尔/升苯并咪唑类药物的5毫升RPMI-1640培养基中（5%二氧化碳，38摄氏度）孵育24小时。然后将寄生虫的虫体从培养基中取出。寄生虫匀浆后，分别使用固相萃取法对寄生虫匀浆和孵育培养基进行萃取。萃取物采用电喷雾电离LC/MS进行分析。结果表明，枝双腔吸虫的酶系统能够进行I相氧化和还原以及II相结合反应。检测到的I相代谢产物包括阿苯达唑亚砜、还原型氟苯达唑和还原型甲苯达唑。至于II相代谢产物，观察到了还原型氟苯达唑和还原型甲苯达唑的甲基衍生物。
