Cvilink Viktor, Skálová Lenka, Szotáková Barbora, Lamka Jirí, Kostiainen Risto, Ketola Raimo A
Department of Biochemical Sciences, Faculty of Pharmacy, Charles University, Heyrovského 1203, 500 05, Hradec Králové, Czech Republic.
Anal Bioanal Chem. 2008 May;391(1):337-43. doi: 10.1007/s00216-008-1863-9. Epub 2008 Mar 17.
Resistance of helminth parasites to common anthelminthics is a problem of increasing importance. The full mechanism of resistance development is still not thoroughly elucidated. There is also limited information about helminth enzymes involved in metabolism of anthelminthics. Identification of the metabolites formed by parasitic helminths can serve to specify which enzymes take part in biotransformation of anthelminthics and may participate in resistance development. The aim of our work was to identify the metabolic pathways of the anthelminthic drugs albendazole (ABZ) and flubendazole (FLU) in Haemonchus contortus, a world-wide distributed helminth parasite of ruminants. ABZ and FLU are benzimidazole anthelminthics commonly used in parasitoses treatment. In our ex vivo study one hundred living adults of H. contortus, obtained from the abomasum of an experimentally infected lamb, were incubated in 5 mL RPMI-1640 medium with 10 micromol L(-1) benzimidazole drug (10% CO(2), 38 degrees C) for 24 h. The parasite bodies were then removed from the medium. After homogenization of the parasites, both parasite homogenates and medium from the incubation were separately extracted using solid-phase extraction. The extracts were analyzed by liquid chromatography-mass spectrometry (LC-MS) with electrospray ionization (ESI) in positive-ion mode. The acquired data showed that H. contortus can metabolize ABZ via sulfoxidation and FLU via reduction of a carbonyl group. Albendazole sulfoxide (ABZSO) and reduced flubendazole (FLUR) were the only phase I metabolites detected. Concerning phase II of biotransformation, the formation of glucose conjugates of ABZ, FLU, and FLUR was observed. All metabolites mentioned were found in both parasite homogenates and medium from the incubation.
蠕虫寄生虫对常见驱虫药产生抗药性是一个日益重要的问题。抗药性产生的完整机制仍未得到充分阐明。关于参与驱虫药代谢的蠕虫酶的信息也有限。鉴定寄生蠕虫形成的代谢产物有助于明确哪些酶参与驱虫药的生物转化，并可能参与抗药性的产生。我们研究的目的是确定驱虫药阿苯达唑（ABZ）和氟苯达唑（FLU）在捻转血矛线虫（一种广泛分布于反刍动物的蠕虫寄生虫）中的代谢途径。ABZ和FLU是常用于治疗寄生虫病的苯并咪唑类驱虫药。在我们的体外研究中，从实验感染羔羊的皱胃中获取的100条活的成年捻转血矛线虫，在含有10 μmol L⁻¹苯并咪唑药物的5 mL RPMI - 1640培养基中（10% CO₂，38℃）孵育24小时。然后将虫体从培养基中取出。虫体匀浆后，寄生虫匀浆和孵育培养基分别采用固相萃取法进行提取。提取物采用液相色谱 - 质谱联用（LC - MS），电喷雾电离（ESI）正离子模式进行分析。获得的数据表明，捻转血矛线虫可通过硫氧化代谢ABZ，通过羰基还原代谢FLU。阿苯达唑亚砜（ABZSO）和还原型氟苯达唑（FLUR）是检测到的仅有的I相代谢产物。关于生物转化的II相，观察到了ABZ、FLU和FLUR的葡萄糖缀合物的形成。上述所有代谢产物在寄生虫匀浆和孵育培养基中均有发现。
