摘要目的：研究严重内质网应激介导糖原合成酶激酶3β（ GSK3β）活性在小鼠急性肝衰竭肝损伤病理机制中的作用。方法以C57BL／6小鼠为研究对象，腹腔注射D-氨基半乳糖（ D-GalN）和脂多糖（ LPS）诱导小鼠急性肝衰竭模型。动物实验分组：阴性对照组（ n＝10）、急性肝衰竭模型组（n＝18）、4-丁酸苯酯（4-PBA，内质网应激抑制剂）干预组（n＝18）和SB216763（GSK3β特异性抑制剂）干预组（n＝16）。检测血清丙氨酸转氨酶（ALT）、天冬氨酸转氨酶（AST）评价肝脏功能，观察肝脏组织病理变化评价肝脏损伤情况，免疫印迹方法检测肝脏组织中蛋白表达水平， GSK3β活性检测试剂盒检测肝脏组织中GSK3β活性改变，四甲基偶氮唑盐（ MTT）法检测细胞生存率。结果体内实验表明，在D-GalN／LPS诱导的急性肝衰竭过程中，内质网应激标志蛋白葡萄糖调节蛋白78（ GRP78）和特异性凋亡分子CCAAT／增强子结合蛋白同源蛋白（CHOP）的表达逐渐升高，提示严重内质网应激被激活，同时GSK3β活性也逐渐升高。4-PBA抑制内质网应激可显著改善肝脏功能[ALT：（365.4±58.6）比（1094.5±201.5）U／L；AST：（555.1±60.8）比（1444.3±533.7）U／L，均P＜0.05]和病理损伤，此外，4-PBA还抑制急性肝衰竭小鼠肝脏中GSK3β的活性（2.6±0.3比4.6±1.3，P＜0.05）。进一步研究表明，抑制GSK3β活性能够下调CHOP和GRP78的表达而改善急性肝衰竭肝损伤。衣霉素诱导肝细胞凋亡的体外实验表明，抑制GSK3β活性能够促进细胞生存。结论在D-GalN／LPS诱导的急性肝衰竭过程中，严重内质网应激通过上调GSK3β活性而促进急性肝衰竭的发生和发展。

abstractsObjective To study the role of endoplasmic reticulum ( ER) stress-mediated glycogen synthase kinase 3β( GSK3β) activity in the pathological process of liver injury in acute liver failure ( ALF) mice.Methods ALF model was established by intraperitoneal injection of D-galactosamine/lipopolysaccharide (D-GalN/LPS) in C57BL/6 mice.The mice were divided into control group (n=10), ALF model group ( n=18 ) , 4-phenylbutyrate ( 4-PBA, an ER stress inhibitor ) group ( n=18 ) and SB216763 (a specific inhibitor of GSK3β) group (n=16).The serum alanine transaminase (ALT) and aspartate transaminase ( AST) levels were measured to reflect the liver function , liver injury was assessed by observing pathological changes of liver tissue , the levels of proteins in liver tissue were analyzed by Western blotting, the activity of GSK3βin liver tissue was detected using GSK3βactivity assay kit, and the survival rate of hepatocyte was measured by methyl thiazolyl tetrazolium ( MTT ) assay.Results In in vivo&nbsp;experiment , the expression levels of ER stress markers , glucose-regulated protein 78 ( GRP78 ) and CCAAT/enhancer-binding protein homologous protein ( CHOP) , were upregulated during the progression of D-GalN/LPS-induced ALF , indicating activation of severe ER stress and increased activity of GSK 3β.Compared with the model group, inhibition of ER stress by 4-PBA improved liver function[ALT:(365.4 ± 58.6) U/L vs (1 094.5 ±201.5) U/L, P<0.05;AST:(555.1 ±60.8) U/L vs (1 444.3 ±533.7) U/L, P<0.05)and pathological injury, also decreased the activity of GSK3β(2.6 ±0.3 vs 4.6 ±1.3, P<0.05).Inhibition of GSK3βactivity was shown to alleviate liver injury in ALF by reducing the expression levels of GRP78 and CHOP.The in vitro experiment of tunicamycin-induced hepatocyte apoptosis showed that inhibition of GSK3βactivity increased the cell survival rate.Conclusion In ALF induced by D-GalN/LPS, severe ER stress may accelerate the development and progress of ALF by upregulating the activity of GSK3β.