Dissociation of covalent binding from the oxidative effects of acetaminophen. Studies using dimethylated acetaminophen derivatives.
Dissociation of covalent binding from the oxidative effects of acetaminophen. Studies using dimethylated acetaminophen derivatives.
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对乙酰氨基酚的氧化作用使共价结合解离。
DOI：
10.1016/0006-2952(88)90686-7
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发表时间：
1988
影响因子：
5.8
通讯作者：
Khairallah,EA
中科院分区：
文献类型：
--
作者：
Birge,RB;Bartolone,JB;Nishanian,EV;Bruno,MK;Mangold,JB;Cohen,SD;Khairallah,EA
10 mM对乙酰氨基酚（APAP）在非诱导小鼠肝细胞原代培养中的细胞毒性作用伴随着细胞内谷胱甘肽（GSH）的耗竭、蛋白质的芳基化和蛋白质巯基（PSH）基团的丧失。对APAP暴露后的共价结合和PSH损失的化学计量学研究表明，PSH的损失比与蛋白质的共价结合所造成的损失更大，这表明APAP在细胞培养中具有氧化和芳酰化作用。亚细胞分离显示APAP诱导的PSH氧化在微粒体部分最大。肝细胞暴露于10 mM 3,5-二甲基-对乙酰氨基酚（3,5- dma）或2,6-二甲基-对乙酰氨基酚（2,6- dma）允许APAP的氧化和芳基化特性解离。尽管用3,5- dma处理培养的肝细胞没有导致共价结合，但与APAP相比，细胞内GSH的消耗、PSH的氧化和细胞毒性都更快。这项研究还提供了第一个证据，证明APAP和3,5- dma的细胞毒性作用都伴随着高分子量蛋白质聚集体的形成，这些蛋白质聚集体不是二硫连接的。这些聚集体可能反映了这些药物的氧化特性，并可能是其毒性作用的中介。相比之下，2,6- dma确实与细胞蛋白结合并消耗谷胱甘肽，但不会导致PSH损失、蛋白质聚集或细胞毒性。由于PSH氧化和蛋白质聚集与细胞毒性密切相关，这些数据表明APAP和3,5- dma的氧化成分可能在诱导培养肝细胞损伤中发挥重要作用。
The cytotoxic effects of 10 mM acetaminophen (APAP) in primary cultures of non-induced mouse hepatocytes are accompanied by depletion of intracellular glutathione (GSH), arylation of protein, and loss of protein sulfhydryl (PSH) groups. Investigation of the stoichiometry of the covalent binding and PSH loss after APAP exposure demonstrated a greater loss in PSH than could be accounted for by covalent binding to proteins and suggests that APAP exhibits both oxidative and arylative actions in cell culture. Subcellular fractionation revealed that the PSH oxidation induced by APAP was greatest in the microsomal fraction. Exposure of the hepatocytes to 10 mM 3,5-dimethyl-acetaminophen (3,5-DMA) or 2,6-dimethyl-acetaminophen (2,6-DMA) permitted dissociation of the oxidative and arylative properties of APAP. Even though treatment of cultured hepatocytes with 3,5-DMA did not result in covalent binding, there was a more rapid depletion of intracellular GSH, oxidation of PSH, and cytotoxicity compared to APAP. This investigation also provides the first evidence that the cytotoxic effects of both APAP and 3,5-DMA are accompanied by the formation of protein aggregates of high molecular weight that are not disulfide linked. The aggregates probably reflect the oxidative properties of these drugs and may be a mediator of their toxic effects. By contrast, 2,6-DMA, which did bind to cellular proteins and deplete GSH, did not lead to PSH loss, protein aggregation, or cytotoxicity. Since PSH oxidation and protein aggregation correlated well with cytotoxicity, these data suggest that the oxidative component of APAP and 3,5-DMA can play a significant role in eliciting cellular damage in cultured hepatocytes.