Mezera V, Kucera O, Moravcova A, Peterova E, Rousar T, Rychtrmoc D, Sobotka O, Cervinkova Z
Department of Physiology, Faculty of Medicine in Hradec Kralove, Charles University in Prague, Hradec Kralove, Czech Republic.
Department of Medical Biochemistry, Faculty of Medicine in Hradec Kralove, Charles University in Prague, Hradec Kralove, Czech Republic.
J Physiol Pharmacol. 2015 Dec;66(6):863-73.
The nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor, important for combating electrophilic and oxidative stress in the liver and other organs. This encompasses detoxification of hepatotoxic drugs, including acetaminophen (APAP). Recently, an association between apolipoprotein E (ApoE) genotype and Nrf2 expression was described. We compared the toxicity of APAP on primary culture hepatocytes isolated from transgenic mice carrying two different human ApoE alleles and wild-type controls. The cells were exposed to APAP in concentrations from 0.5 to 4 mM for up to 24 hours. APAP led to a dose-dependent hepatotoxicity from 1 mM after 16 h exposure in all mice tested. The toxicity was higher in hepatocytes isolated from both transgenic strains than in wild-type controls and most pronounced in ApoE3 mice. Concurrently, there was a decline in mitochondrial membrane potential, especially in ApoE3 hepatocytes. The formation of reactive oxygen species was increased after 24 hours with 2.5 mM APAP in hepatocytes of all strains tested, with the highest increase being in the ApoE3 genotype. The activity of caspases 3 and 7 did not differ among groups and was minimal after 24 hour incubation with 4 mM APAP. We observed higher lipid accumulation in hepatocytes isolated from both transgenic strains than in wild-type controls. The expression of Nrf2-dependent genes was higher in ApoE3 than in ApoE4 hepatocytes and some of these genes were induced by APAP treatment. In conclusion, transgenic mice with ApoE4 and ApoE3 alleles displayed higher susceptibility to acute APAP toxicity in vitro than wild-type mice. Of the two transgenic genotypes tested, ApoE3 allele carriers were more prone to injury.
核因子红细胞2相关因子2（Nrf2）是一种转录因子，对抵抗肝脏和其他器官中的亲电及氧化应激至关重要。这包括对肝毒性药物（如对乙酰氨基酚（APAP））的解毒作用。最近，有人描述了载脂蛋白E（ApoE）基因型与Nrf2表达之间的关联。我们比较了APAP对从携带两种不同人类ApoE等位基因的转基因小鼠和野生型对照分离的原代培养肝细胞的毒性。将细胞暴露于浓度为0.5至4 mM的APAP中长达24小时。在所有测试小鼠中，暴露16小时后，从1 mM起，APAP导致剂量依赖性肝毒性。两种转基因品系分离的肝细胞中的毒性均高于野生型对照，在ApoE3小鼠中最为明显。同时，线粒体膜电位下降，尤其是在ApoE3肝细胞中。在所有测试品系的肝细胞中，用2.5 mM APAP处理24小时后，活性氧的形成增加，ApoE3基因型的增加最为显著。各实验组中半胱天冬酶3和7的活性无差异，用4 mM APAP孵育24小时后活性最低。我们观察到，两种转基因品系分离的肝细胞中的脂质积累均高于野生型对照。ApoE3肝细胞中Nrf2依赖性基因的表达高于ApoE4肝细胞，其中一些基因可被APAP处理诱导。总之，携带ApoE4和ApoE3等位基因的转基因小鼠在体外对急性APAP毒性的易感性高于野生型小鼠。在测试的两种转基因基因型中，ApoE3等位基因携带者更容易受到损伤。
