Mechanism of azathioprine-induced injury to hepatocytes: roles of glutathione depletion and mitochondrial injury
Mechanism of azathioprine-induced injury to hepatocytes: roles of glutathione depletion and mitochondrial injury
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DOI：
10.1016/s0168-8278(01)00196-9
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发表时间：
2001-12-01
影响因子：
25.7
通讯作者：
Farrell, GC
中科院分区：
文献类型：
--
作者：
Lee, AU;Farrell, GC
背景/目标：我们寻求证据表明，硫唑嘌呤导致细胞死亡，通过还原型谷胱甘肽（GSH）耗尽和线粒体injuries.Methods：研究进行了原代培养的大鼠肝细胞和培养的Hep G2细胞。先前的GSH耗竭（通过丁硫氨酸亚砜亚胺治疗）增强了毒性，而补充GSH或N-乙酰半胱氨酸具有保护作用。在肝细胞中，GSH在硫唑嘌呤代谢为6-巯基嘌呤的过程中被消耗。6-巯基嘌呤对肝细胞无毒性，表明硫唑嘌呤代谢的后期步骤与致病机制无关。在Hep G2细胞中，硫唑嘌呤没有改变GSH水平，也没有毒性。超微结构研究显示，肝细胞线粒体损伤后暴露于硫唑嘌呤，但没有凋亡的功能。硫唑嘌呤产生快速和深刻的三磷酸腺苷（ATP）耗竭。环孢菌素A和甘氨酸提供了对硫唑嘌呤毒性的保护，和Trolox和高剂量的别嘌呤醇也衰减injure.Conclusions：硫唑嘌呤对肝细胞的毒性机制涉及耗竭GSH导致线粒体损伤，ATP和细胞坏死死亡的深刻消耗。通过有效的抗氧化剂甘氨酸和阻断线粒体渗透性转换孔来防止细胞死亡。(C)2001年由Elsevier Science B. V.代表欧洲肝脏研究协会出版。
Background/Aims: We sought evidence that azathioprine causes cell death through reduced glutathione (GSH) depletion and mitochondrial injury.Methods: Studies were conducted in primary cultures of rat hepatocytes and cultured Hep G2 cells.Results: Azathioprine toxicity to rat hepatocytes was preceded by depletion of GSH. Prior GSH depletion (by treatment with buthionine sulfoximine) enhanced toxicity whilst supplemental GSH or N-acetyleysteine was protective. In hepatocytes, GSH is consumed during metabolism of azathioprine to 6-mercaptopurine. 6-Mercaptopurine was not toxic to hepatocytes, suggesting that the later steps in azathioprine metabolism were not related to the pathogenic mechanism. In Hep G2 cells, azathioprine did not alter levels of GSH and was not toxic. Ultrastructural studies showed hepatocyte mitochondrial lesions after exposure to azathioprine, but no features of apoptosis. Azathioprine produced rapid and profound depletion of adenosine 5'-triphosphate (ATP). Cyclosporin A and glycine afforded protection against azathioprine toxicity, and Trolox and high-dose allopurinol also attenuated injury.Conclusions: The mechanism of azathioprine toxicity to hepatocytes involves depletion of GSH leading to mitochondrial injury with profound depletion of ATP and cell death by necrosis. Cell death was prevented by potent antioxidants, glycine and blocking the mitochondrial permeability transition pore. (C) 2001 Published by Elsevier Science B.V. on behalf of the European Association for the Study of the Liver.