Abundance of Four Sulfur Mustard-DNA Adducts ex Vivo and in Vivo Revealed by Simultaneous Quantification in Stable Isotope Dilution-Ultrahigh Performance Liquid Chromatography-Tandem Mass Spectrometry

作者：Yue Lijun; Wei Yuxia; Chen Jia; Shi Huiqin; Liu Qin; Zhang Yajiao; He Jun; Guo Lei^*; Zhang Tingfen; Xie Jianwei; Peng Shuangqing

来源：Chemical Research in Toxicology, 2014, 27(4): 490-500.

DOI：10.1021/tx4003403

Sulfur mustard (SM) is a highly reactive alkylating vesicant and causes blisters upon contact with skin, eyes, and respiratory organs. It covalently links with DNAs by forming four mono- or cross-link adducts. In this article, the reference standards of SM-DNA adducts and deuterated analogues were first synthesized with simplified procedures containing only one or two steps and using less toxic chemical 2-(2-chloroethylthio)ethanol or nontoxic chemical thiodiglycol as starting materials. A sensitive and high-throughput simultaneous quantification method of N7-[2-[(2-hydroxyethyl)thio]-ethyl]guanine (N-7-HETEG), O-6-[2-[(2-hydroxyethyl)thio]-ethyl]guanine (O-6-HETEG), N7-[2-[(2-hydroxyethyl)thio]-ethyl]adenine N-3-[2-(N-3-HETEA), and bis[2-(guanin-7-yl)ethyl]sulfide (Bis-G) in the Sprague Dawley rat derma samples was developed by stable isotope dilution ultrahigh performance liquid chromatography tandem mass spectrometry (ID-UPLC-MS/MS) with the aim of revealing the real metabolic behaviors of four adducts. The method was validated, the limit of detection (S/N ratio greater than 10) was 0.01, 0.002, 0.04, and 0.11 fmol on column for N-7-HETEG, O-6-HETEG, Bis-G, and N-3-HETEA, respectively, and the lower limit of quantification (S/N ratio greater than 20) was 0.04, 0.01, 0.12, and 0.33 frnol on column for N7-HETEG, O-6-HETEG, Bis-G, and N-3-HETEA, respectively. The accuracy of this method was determined to be 76% to 129% (n = 3), and both the interday (n = 6) and intraday (n = 7) precisions were less than 10%. The method was further applied for the quantifications of four adducts in the derma of adult male Sprague Dawley rats exposed to SM ex vivo and in vivo, and all adducts had time and dose effect relationships. To the best of our knowledge, this is the first time that the real presented status of four DNA adducts was simultaneously revealed by the MS-based method, in which Bis-G showed much higher abundance than the result previously reported and N-3-HETEA showed much less. It should be noted that since the interstrand cross-linked adduct is believed to stall DNA replication and finally induce a double-strand break, the higher abundance of Bis-G is a great indication of a more serious DNA lesion by SM alkylation.

• 出版日期2014-4
• 单位中国人民解放军军事医学科学院