Oxidation state specific analysis of arsenic species in tissues of wild-type and arsenic(+3 oxidation state)methyltransferase-knockout mice

作     者：Jenna M.Currier Christelle Douillet Zuzana Drobná Miroslav Styblo 

作者机构：Curriculum in Toxicology University of North Carolina at Chapel Hill Department of Nutrition Gillings School of Global Public Health University of North Carolina at Chapel Hill 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2016年第28卷第11期

页      面：104-112页

核心收录：

学科分类：083002[工学-环境工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 07[理学] 08[工学] 09[农学] 0903[农学-农业资源与环境] 0713[理学-生态学] 

基　　金：supported by NIH grant No. 2 R01 ES010845 to M.S the UNC Nutrition Obesity Research Center grant no. DK056350, NIH grant No. P30ES010126 to the UNC Center for Environmental Health and Susceptibility supported by a pre-doctoral traineeship (National Research Service Award T32 ES007126) from the National Institute of Environmental Health Sciences, NIH 

主　　题：Arsenic speciation analysis Hydride generation cryotrapping atomic absorption spectrometry Arsenic(+ 3 oxidation state) methyltransferase As3mt knockout mice 

摘      要：Arsenic methyltransferase（As3mt） catalyzes the conversion of inorganic arsenic（i As） to its methylated metabolites, including toxic methylarsonite（MAs~Ⅲ） and dimethylarsinite（DMAs~Ⅲ）. Knockout（KO） of As3 mt was shown to reduce the capacity to methylate i As in mice. However, no data are available on the oxidation states of As species in tissues of these mice. Here, we compare the oxidation states of As species in tissues of male C57BL/6 As3mt-KO and wild-type（WT） mice exposed to arsenite（iA s~Ⅲ） in drinking water. WT mice were exposed to50 mg/L As and As3mt-KO mice that cannot tolerate 50 mg/L As were exposed to 0, 15, 20, 25 or30 mg/L As. iA s~Ⅲaccounted for 53% to 74% of total As in liver, pancreas, adipose, lung, heart, and kidney of As3mt-KO mice; tri- and pentavalent methylated arsenicals did not exceed 10% of total As. Tissues of WT mice retained iA s and methylated arsenicals： iA s~Ⅲ, MAs~Ⅲand DMAs~Ⅲ represented 55%‐68% of the total As in the liver, pancreas, and brain. High levels of methylated species, particularly MAs~Ⅲ, were found in the intestine of WT, but not As3mt-KO mice,suggesting that intestinal bacteria are not a major source of methylated As. Blood of WT mice contained significantly higher levels of As than blood of As3mt-KO mice. This study is the first to determine oxidation states of As species in tissues of As3mt-KO mice. Results will help to design studies using WT and As3mt-KO mice to examine the role of iA s methylation in adverse effects of iA s exposure.