Enhanced expressions and activations of leukotriene C4 synthesis enzymes in D-galactosamine/lipopolysaccharide-induced rat fulminant hepatic failure model.
Enhanced expressions and activations of leukotriene C4 synthesis enzymes in D-galactosamine/lipopolysaccharide-induced rat fulminant hepatic failure model.
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DOI：
10.3748/wjg.14.2748
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发表时间：
2008-05
影响因子：
4.3
通讯作者：
Kui-fen Ma;Hong-yu Yang;Zhe Chen;L. Qi;Danyan Zhu;Y. Lou
中科院分区：
文献类型：
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作者：
Kui-fen Ma;Hong-yu Yang;Zhe Chen;L. Qi;Danyan Zhu;Y. Lou
目的探讨D-氨基半乳糖/脂多糖（D-GalN/ LPS）诱导的暴发性肝衰竭（FHF）大鼠模型中白三烯C4（LTC 4）合成酶的表达和活性变化及其与半胱氨酰白三烯（cys-LT）生成的关系。方法采用D-GalN（300 mg/kg）+LPS（0.1 mg/kg）灌胃大鼠1、3、6、12 h。采用酶免疫法测定肝细胞胞浆LT含量。采用逆转录-聚合酶链反应（RT-PCR）、免疫印迹（Western blot）和免疫组织化学方法检测类花生酸和谷胱甘肽（MAPEG）代谢超家族膜相关蛋白LTC 4合成酶的表达和定位。通过使用高效液相色谱法（HPLC）测定与肝微粒体孵育后的LTA 4产物，评价LTC 4合成酶的活性。结果D-GalN/LPS可引起肝脏损伤，并在肝损伤早期出现cys-LT蓄积。LTC 4合成酶（LTC 4S）和微粒体谷胱甘肽-S-转移酶（mGST）2在大鼠肝脏中表达，而后者特异性地位于肝细胞中。D-GalN/LPS处理后，其mRNA和蛋白表达在早期即上调。同时，检测到更高的LTC 4合成酶活性，尽管LTC 4S的活性在这种情况下起主要作用。结论大鼠FHF模型中LTC 4S和mGST 2的表达和活性均上调，至少部分参与了cys-LT在肝脏的蓄积。
AIM To investigate the expression and activity of leukotriene C4 (LTC4) synthesis enzymes and their underlying relationship with cysteinyl leukotriene (cys-LT) generation in a rat fulminant hepatic failure (FHF) model induced by D-galactosamine/lipopolysaccharide (D-GalN/ LPS). METHODS Rats were treated with D-GalN (300 mg/kg) plus LPS (0.1 mg/kg) for 1, 3, 6, and 12 h. Enzyme immunoassay was used to determine the hepatic cys-LT content. Reverse transcription-polymerase chain reaction (RT-PCR), Western blot or immunohistochemical assay were employed to assess the expression or location of LTC4 synthesis enzymes, which belong to membrane associated proteins in eicosanoid and glutathione (MAPEG) metabolism superfamily. Activity of LTC4 synthesis enzymes was evaluated by determination of the products of LTA4 after incubation with liver microsomes using high performance liquid chromatography (HPLC). RESULTS Livers were injured after treatment with D-GalN/LPS, accompanied by cys-LT accumulation at the prophase of liver injury. Both LTC4 synthase (LTC4S) and microsomal glutathione-S-transferase (mGST) 2 were expressed in the rat liver, while the latter was specifically located in hepatocytes. Their mRNA and protein expressions were up-regulated at an earlier phase after treatment with D-GalN/LPS. Meantime, a higher activity of LTC4 synthesis enzymes was detected, although the activity of LTC4S played the main role in this case. CONCLUSION The expression and activity of both LTC4S and mGST2 are up regulated in a rat FHF model, which are, at least, partly responsible for cys-LT hepatic accumulation.