Serrano Jose, Kolanczyk Richard C, Blackwell Brett R, Sheedy Barbara R, Tapper Mark A
Office of Research and Development, Center for Computational Toxicology and Exposure, Great Lakes Toxicology and Ecology Division, United States Environmental Protection Agency, Duluth, MN, USA.
Xenobiotica. 2021 May;51(5):536-548. doi: 10.1080/00498254.2020.1840658. Epub 2021 Mar 15.
Thiacloprid (THI) is a widely used neonicotinoid insecticide where concerns have been raised regarding low absorption by crops, substantial distribution in surrounding areas, and potential adverse effects to terrestrial and aquatic organisms.Prior to this study, there was very limited information addressing the (precision-cut liver slices) metabolism of THI by fish species and the metabolic pathways regulating its potential for adverse effects.The and biotransformation pathway of THI is defined by the formation of three primary metabolites (TM1, TM2 and TM3) via separate paths differentiated by reductive decyanation, reductive dechlorination with hydration and dealkylation processes, respectively.Kinetic rates were calculated for the rat microsomal decyanation of THI into TM1 ( = 299.2 µM and = 5.3 pmol/min/mg), and for the dealkylation of THI into TM3 ( = 368.9 µM and = 3.95 pmol/min/mg).Formation confirmation and identity inference of THI metabolites in absence of standards were achieved by LC-UV and High Resolution-MS strategies.The and metabolic products of THI are conserved both across species (rat and Rainbow trout) and levels of biological organization (microsomes and liver slices), as previously reported for the neonicotinoid insecticides Imidacloprid and Acetamiprid.
噻虫啉(THI)是一种广泛使用的新烟碱类杀虫剂,人们对其在作物中的低吸收率、在周边地区的大量分布以及对陆地和水生生物的潜在不利影响表示担忧。在本研究之前,关于鱼类对THI的(精密切割肝切片)代谢以及调节其潜在不利影响的代谢途径的信息非常有限。THI的生物转化途径是通过分别经由还原脱氰、加水还原脱氯和脱烷基化过程形成三种主要代谢物(TM1、TM2和TM3)来定义的。计算了大鼠微粒体将THI脱氰生成TM1的动力学速率(Km = 299.2 μM,Vmax = 5.3 pmol/min/mg),以及将THI脱烷基生成TM3的动力学速率(Km = 368.9 μM,Vmax = 3.95 pmol/min/mg)。在没有标准品的情况下,通过LC-UV和高分辨率质谱策略实现了THI代谢物的形成确认和身份推断。正如先前对新烟碱类杀虫剂吡虫啉和啶虫脒的报道,THI的代谢产物在物种(大鼠和虹鳟鱼)和生物组织水平(微粒体和肝切片)上都是保守的。