酒精性肝病中蛋白酶体活性抑制与内质网应激相关性的体外实验  

In vitro study of the correlation between inhibited ubiquitin proteasome activity and endoplasmic reticulum stress in alcoholic liver disease

作　　者：关慧[1] 刘慧敏[1] 贾晓青[1] 罗争[1] 阎明[1] 

机构地区：[1]山东大学齐鲁医院消化内科,济南250012

出　　处：《山东大学学报（医学版）》2011年第8期52-56,共5页Journal of Shandong University:Health Sciences

摘　　要：目的探讨酒精性肝病中蛋白酶体活性的抑制与内质网应激间的相关性。方法乙醇处理HepG2细胞建立酒精性肝损伤体外模型。设立对照组、乙醇处理组、蛋白酶体活化剂桦木酸处理组及桦木酸加乙醇共同处理组,测定各组内质网应激标志物葡萄糖调节蛋白78(g lucose regu lation protein78,GRP78)基因表达水平的变化,同时测定蛋白酶体活性和细胞内甘油三酯含量。结果乙醇处理组蛋白酶体活性降低,GRP78表达增高,细胞内甘油三酯含量增多;而桦木酸组结果相反;蛋白酶体活性变化与GRP78表达水平呈负相关,GRP78表达水平与甘油三酯含量呈正相关。结论乙醇处理可通过抑制蛋白酶体活性诱发内质网应激;桦木酸可提高蛋白酶体活性而降低内质网应激严重程度;蛋白酶体活性变化与内质网应激严重程度呈负相关性,后者可加剧酒精性肝损伤。Objective To study the potential correlation between inhibited proteasome activity and occurrence and development of endoplasmic reticulum stress （ERS） in alcoholic liver disease （ALD）. Methods HepG2 cells were lxeated with ethanol to establish an in vitro model of ALD, and then treated with betulinic acid or with both ethanol and betulinic acid. MRNA expression of glucose regulation protein 78 （ GRP78）, an ERS marker, was detected. Also, proteasome activity and intracellular triglyceride（TG） content in different groups were detected. Results Ethanol inhibited activity of proteasome, with increases of GRP78 mRNA expression and intracellular TG content. Betulinic acid promoted proteasome activity with reductions of GRP78 mRNA level and TG content. Correlation analysis revealed a negative relativity between proteasome activity and expression of GRP78 mRNA, while the GRF78 mRNA level and intracellular TG content had positive relativity. Conclusion Ethanol can inhibit proteasome activity, thus inducing ERS, while betulinic acid can promote proteasome activity, thus reducing ERS. Proteasome activity and ERS have some negative relativity, and the latter aggravates the pathogenesis of ALD.

关 键 词：肝病 酒精性 内质网应激 泛素蛋白酶体 

分 类 号：R575.5[医药卫生—消化系统]