College of Pharmaceutical Sciences, Zhejiang University, Zhejiang 310058, China; Department of Chemistry, Zhejiang University, Zhejiang 310027, China.
Department of Chemistry, Zhejiang University, Zhejiang 310027, China.
J Hazard Mater. 2020 Mar 5;385:121564. doi: 10.1016/j.jhazmat.2019.121564. Epub 2019 Nov 7.
Perfluorooctane sulfonyl fluoride (PFOSF) is the precursor of many fluorochemicals that are ubiquitous in the environment. However, its distribution and toxicology are rarely studied. In this work, the oxidability of PFOSF was found. PFOSF can accelerate oxidation of glutathione (GSH) to its oxidized form GSSG, and itself is reduced to a sulfinic acid. The yielded sulfinic acid was prepared and identified with high resolution mass spectrometry and NMR. Similar redox reactions were observed for PFOSF's short chain alternatives. The reduction potentials of perfluoroalkane sulfonyl fluorides (PFASFs) were determined to be -2.13 V vs. SCE with cyclic voltammetry, further demonstrating their oxidability. The peptide mixtures of GSH plus another cysteine-containing peptide were also oxidized by PFASFs to GSSG and an asymmetric disulfide GS-S-PEP. A single short-sequence PEP-SH could be oxidized to the symmetric disulfide PEP-S-S-PEP as the final product. In vitro experiments were carried out by adding PFASFs into rat liver S9 fractions. The turnover ratio of PFASFs were calculated to be about 4-10% by quantification of sulfinic acid with LC-MS/MS. Our work illustrates one of the potential metabolic pathways of PFASFs and demonstrates the oxidation of PEP-SHs by PFASFs, thus providing a preliminary exploration in the toxicology of these fluorochemicals.
全氟辛烷磺酰氟（PFOSF）是许多在环境中普遍存在的氟化学品的前体。然而，其分布和毒理学很少被研究。在这项工作中，发现了 PFOSF 的氧化性。PFOSF 可以加速谷胱甘肽（GSH）氧化为其氧化形式 GSSG，自身还原为亚磺酸。生成的亚磺酸用高分辨率质谱和 NMR 进行了制备和鉴定。PFOSF 的短链替代品也观察到了类似的氧化还原反应。通过循环伏安法测定全氟烷磺酰氟（PFASFs）的还原电位为-2.13 V 与 SCE 相比，进一步证明了它们的氧化性。GSH 与另一个含半胱氨酸的肽的混合肽也被 PFASFs 氧化为 GSSG 和不对称二硫键 GS-S-PEP。单一短序列 PEP-SH 可以被氧化为最终产物对称二硫键 PEP-S-S-PEP。通过向大鼠肝 S9 级分中添加 PFASFs 进行了体外实验。通过 LC-MS/MS 定量亚磺酸计算出 PFASFs 的周转率约为 4-10%。我们的工作说明了 PFASFs 的一种潜在代谢途径，并证明了 PFASFs 对 PEP-SHs 的氧化作用，从而为这些氟化学品的毒理学提供了初步探索。
