Objective: To investigate the role of the glycogen synthase kinase 3β (GSK3β) and the peroxisome proliferator-activated receptor alpha (PPARα) signaling pathway in acute liver failure and related mechanisms in a mouse model of acute liver failure induced by D-galactosamine/lipopolysaccharide (D-GalN/LPS). Methods: C57BL/6 mice were given intraperitoneal injection of D-GalN/LPS to establish a mouse model of acute liver failure. SB216763 was used to inhibit the activity of GSK3β and PPARα siRNA was used to inhibit the expression of PPARα. Western blotting was used to measure the expression of PPARα protein. The changes in liver pathology were observed to evaluate liver injury, and the serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured to assess liver function. Quantitative real-time PCR was used to measure the mRNA expression of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-12p40 (IL-12p40), and PPARα. A one-way analysis of variance was used for comparison of means between multiple groups; the least significant difference test was used for data with homogeneity of variance, and the Games-Howell method was used for data with heterogeneity of variance. Results: In the mice with liver failure induced by D-GalN/LPS, GSK3β inhibition promoted the mRNA and protein expression of PPARα (F = 13.18 and 301.36, P = 0.00 and 0.00). In the mice with acute liver failure induced by D-GalN/LPS, GSK3β inhibition alleviated liver bleeding, inflammation, and necrosis and reduced the serum levels of ALT (F = 25.16, P = 0.000) and AST (F = 12.96, P = 0.001), as well as the mRNA expression of TNF-α (F = 32.17, P = 0.00), IL-1β (F = 11.57, P = 0.005), and IL-12p40 (F = 14.17, P = 0.015) in liver tissue. The inhibition of PPARα expression reversed the liver-protecting effect of GSK3β inhibition, which manifested as aggravation in liver bleeding, inflammation, and necrosis, increases in the serum levels of ALT (F = 25.16, P = 0.001) and AST (F = 12.96, P = 0.000), and an increase in the mRNA expression of TNF-α (F = 32.17, P = 0.00), IL-1β (F = 11.57, P = 0.024), and IL-12p40 (F = 14.17, P = 0.001) in liver tissue. Conclusion: In mice with acute liver failure induced by D-GalN/LPS, the GSK3β-PPARα-inflammatory factor signaling pathway may play an important role. GSK3β inhibition has a protective effect in mice with acute liver failure possibly by activating the inhibitory inflammatory factor of PPARα.
目的： 用D-氨基半乳糖/脂多糖（D-GalN/LPS）诱导的小鼠急性肝衰竭模型，探讨糖原合成酶激酶3（GSK3）β和过氧化物酶体增殖物激活受体（PPAR）α信号通路在急性肝衰竭中的作用及其机制。 方法： 以C57BL/6小鼠为研究对象，腹腔注射D-GalN/LPS建立小鼠急性肝衰竭模型。用SB216763抑制GSK3β活性，用PPARα siRNA抑制PPARα表达。Western blot检测小鼠中PPARα蛋白表达情况。观察小鼠肝组织病理变化情况以评价肝脏损伤情况，检测血清丙氨酸氨基转移酶（ALT）、天冬氨酸氨基转移酶（AST）评价肝脏功能。实时荧光定量PCR检测肝组织中肿瘤坏死因子（TNF）α、白细胞介素（IL）-1β、IL-12p40 mRNA和PPARα基因表达水平。多组样本均数的比较采用单因素方差分析，方差齐者用LSD检验，方差不齐者用Games-Howell法。 结果： 在D-GalN/LPS诱导的肝衰竭小鼠中，抑制GSK3β活性促进了PPARα的mRNA（0.29±0.05与0.17±0.02，F = 13.18，P < 0.01）和蛋白（0.79±0.05与0.15±0.04，F = 301.36，P < 0.01）表达水平。在D-GalN/LPS诱导的急性肝衰竭小鼠中，抑制GSK3β活性减轻了小鼠肝脏出血、炎症和坏死，降低了血清肝功能指标ALT（572.0±127.8与1 627.0±412.4，F = 25.16，P < 0.01）、AST（479.2±229.2与1 359.0±534.8，F = 12.96，P < 0.01）水平，也降低了肝组织中炎症因子TNFα（F = 32.17，P < 0.01）、IL-1β（F = 11.57，P < 0.01）、IL-12p40 （F = 14.17，P < 0.01）mRNA表达水平。抑制PPARα表达逆转了GSK3β活性抑制带来的肝保护性作用，表现在肝脏出血、炎症和坏死加重，血清肝功能指标ALT（1 433.0±464.0与708.7±196.2，F = 25.16，P < 0.01）、AST（1 361.0±583.2与352.7±177.4，F = 12.96，P < 0.01）水平升高，肝组织中炎症因子TNFα（F = 32.17，P < 0.01）、IL-1β（F = 11.57，P < 0.01）、IL-12p40（F = 14.17，P < 0.01）mRNA表达水平升高。 结论： 在D-GalN/LPS诱导的小鼠急性肝衰竭中，GSK3β-PPARα-炎症因子通路是重要的分子信号通路之一，抑制GSK3β活性可能通过激活PPARα抑制炎症因子对急性肝衰竭小鼠发挥保护性作用。.
Keywords: D-Galactosamine; Glycogen synthase kinase 3β; Inflammation; Lipopolysaccharides; Liver failure; Peroxisome proliferator activated receptors α.