为探究香叶木素对对乙酰氨基酚（APAP）诱导的急性肝脏损的保护作用及机制，体外实验人非肿瘤性肝细胞LO2设置空白组及不同浓度香叶木素（Dios）预处理组处理6 h后，给予APAP（10 mM）孵育24 h。体内实验40只C57BL/6 J小鼠随机分为正常组、APAP组、Dios 30 mg/kg和Dios 60 mg/kg剂量组。每组10只，Dios组小鼠给予不同剂量的Dios灌胃1次，连续7 d。实验末期，除正常组其余各组给予APAP 300 mg/kg建立急性肝损伤模型，测定小鼠血清ALT、AST；肝GSH、MDA水平；HE染色；Western blot法检测Nrf2的表达；PCR检测mNqo1，mG6pdx，mSOD2的表达。结果表明在LO2细胞中，与APAP组相比，Dios预处理组可以恢复细胞活力和GSH含量。高剂量组可以明显降低小鼠血清ALT、AST水平，下调肝组织MDA表达并提高GSH含量，进而诱导Nrf2转位入核，其下游相关基因Nqo1、G6pdx、SOD2也显著上升。高剂量组可保护APAP引起的急性肝损伤，并且该保护作用与激活抗氧化应激Nrf2/ARE 信号通路有关。

In order to examine the protective effect of diosmetin against acetaminophen-induced hepatotoxicity in vitro and vivo, Human non-tumor hepatic cells LO2 were pretreated with either vehicle or Dios (15, 30 μM), for 6h, followed by incubation with or without APAP (10 mM) for 24 h. In an in vivo assay, male C57BL/6J mice were randomly divided into control group, APAP group, low dose Dios group (30 mg/kg) and high dose Dios group (60 mg/kg). Each group included 10 mice. The mice were treated with different doses of diosmetin once daily for consecutive 7 days. At the end of the experiment, acetaminophen (300 mg/kg) was given intragastrically to induce liver injury in all groups except for the control group. Twenty-four hours later, the levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) were detected. The contents of glutathione (GSH) and malondiadehyde (MDA) in liver tissue homogenates were measured through commercial kits. HE staining was performed to observe pathologic changes of the liver. The protein expression of Nrf2 was detected by Western blotting and the mRNA expressions of Nqo1, G6pdx, SOD2 was tested by quantitative real-time PCR. The results showed that in LO2 cells, APAP exposure decreased the cell viability and glutathione (GSH) content, which were both greatly restored by Dios pretreatment. Compared with the model group, the serum activities of ALT and AST as well as MDA content remarkably decreased by the administration of diosmetin (60 mg/kg), while GSH contents were elevated in liver tissues; Nrf2 protein expression in the nucleus as well as mRNA expressions of Nqo1, G6pdx, SOD2 increased. High-dose diosmetin can inhibit acetaminophen-induced hepatotoxicity, and the mechanism may be associated with the activation of Nrf2 /ARE signaling pathway.

国家自然科学基金项目（81100281）