Wang Min, Gorrell Mark D, Abbott Catherine A, Jaggi Rene, Marguet Didier, Dickinson Ronald G
Department of Medicine, University of Queensland, Royal Brisbane Hospital, Brisbane, Australia.
J Gastroenterol Hepatol. 2002 Jan;17(1):66-71. doi: 10.1046/j.1440-1746.2002.02662.x.
Zomepirac (ZP), a non-steroidal anti-inflammatory drug (NSAID), has been reported to cause immune-mediated liver injury. In vivo, ZP is metabolized to a chemically reactive acyl glucuronide conjugate (ZAG) which can undergo covalent adduct formation with proteins. Such acyl glucuronide-derived drug-protein adducts may be important in the development of immune and toxic responses caused by NSAID. We have shown using immunoabsorptions that the 110 kDa CD26 (dipeptidyl peptidase IV) is one of the hepatic target proteins for covalent modification by ZAG. In the present study, a CD26-deficient mouse strain was used to examine protein targets for covalent modification by ZP/metabolites in the liver.
The CD26-deficient phenotype was confirmed by immunohistochemistry, flow cytometry analysis, RT-PCR, enzyme assay and immunoblotting. Moreover, by using monoclonal antibody immunoblots, CD26 was not detected in the livers of ZP-treated CD26-deficient mice. Immunoblots using a polyclonal antiserum to ZP on liver from ZP-treated mice showed three major sizes of protein bands, in the 70, 110 and 140 kDa regions. Most, but not all, of the anti-ZP immunoreactivity in the 110 kDa region was absent from ZP-treated CD26-deficient mice.
These data definitively showed that CD26 was a component of ZP-modified proteins in vivo. In addition, the data suggested that at least one other protein of approximately 110 kDa was modified by covalent adduct formation with ZAG.
唑美辛（ZP）是一种非甾体抗炎药（NSAID），据报道可引起免疫介导的肝损伤。在体内，ZP代谢为具有化学反应性的酰基葡萄糖醛酸共轭物（ZAG），后者可与蛋白质形成共价加合物。这种源自酰基葡萄糖醛酸的药物 - 蛋白质加合物可能在NSAID引起的免疫和毒性反应的发生中起重要作用。我们通过免疫吸附法表明，110 kDa的CD26（二肽基肽酶IV）是ZAG共价修饰的肝脏靶蛋白之一。在本研究中，使用CD26缺陷小鼠品系来检查肝脏中被ZP/代谢物共价修饰的蛋白质靶标。
通过免疫组织化学、流式细胞术分析、RT-PCR、酶测定和免疫印迹法确认了CD26缺陷表型。此外，通过使用单克隆抗体免疫印迹法，在经ZP处理的CD26缺陷小鼠的肝脏中未检测到CD26。用针对ZP的多克隆抗血清对经ZP处理的小鼠肝脏进行免疫印迹，显示在70、110和140 kDa区域有三种主要大小的蛋白条带。在经ZP处理的CD26缺陷小鼠中，110 kDa区域的大部分（但不是全部）抗ZP免疫反应性缺失。
这些数据明确表明CD26是体内ZP修饰蛋白的一个组成部分。此外，数据表明至少还有一种约110 kDa的其他蛋白质通过与ZAG形成共价加合物而被修饰。
