细胞外组蛋白在急性肝衰竭小鼠中的变化

Changes of extracellular histones in mice with acute liver failure and its therapeutic potential WEN

目的研究急性肝衰竭小鼠细胞外组蛋白的水平变化及干预价值。方法选野生型C57BL／6小鼠，经腹腔注射致死剂量的D-氨基半乳糖和脂多糖诱导急性肝衰竭，动态测定血浆中细胞外组蛋白的水平以及肝功能、细胞凋亡等指标；分别给予特异性抗组蛋白H3和H4中和抗体进行干预，并检测小鼠生存率和肝损伤指标以及肿瘤坏死因子TNF-α水平等。结果D-氨基半乳糖和脂多糖联用导致小鼠急性肝衰竭，表现为血浆ALT水平明显升高，大量肝细胞凋亡和坏死，所有小鼠于9—12h内死亡；染毒后小鼠细胞外组蛋白水平呈时间依赖方式明显增高，和对照组相比差异具有统计学意义（P〈0．01）。染毒小鼠分别经特异性抗组蛋白中和抗体H3和H4干预后，病死率明显下降（P：0．037，P=0．025），其机制可能与抑制TNF-α水平有关。结论细胞外组蛋白是肝衰竭发病过程中的重要炎性介质，以细胞外组蛋白为靶点进行干预可能是今后重型肝炎治疗的新策略，值得深入探讨。

Objective To investigate the changes of extracellular histones during the course of acute liver failure in mice as well as its therapeutic potential. Methods WT mice （C57BL/6） were randomly （random number） allocated to inducing acute liver failure by lethal doses of GalN/LPS injected i. p. Hepatic function, apoptosis of hepatocytes and histological indexes were measured at different intervals following GalN/LPS challenge. The levels of extracellular histones were determined by using ELISA and Western blot methods. Meanwhile, GalN/LPS-treated mice were administered with anti-histone H3 and antihistone H4 neutralized antibodies, respectively. Results Administration of GalN/LPS to mice caused acute liver failure, characterized by significant elevation of plasma ALT levels and massive hepatocyte apoptosis or necrosis. All mice died within 9-12 hours. The levels of nucleosomes and extracellular histones H3 and H4 were increased considerably in a time - dependent manner. The survival rates in GaIN/LPS-treated mice were improved remarkably following administration of anti-histone H3 and H4 neutralized antibodies （P = 0. 037, P = 0. 025）, likely due to the significant inhibition of TNF-production. Conclusions Extracellular histones are an important mediator implicated in the pathogenesis of acute liver failure. Anti - histones show promising potential in the treatment of acute liver failure, which deserves further investigation in the future.