Shi Xiaoxia, Li Dangdang, Deng Qinghua, Peng Zhicheng, Zhao Chenxu, Li Xiaobing, Wang Zhe, Li Xinwei, Liu Guowen
Key Laboratory of Zoonosis,Ministry of Education,College of Veterinary Medicine, Jilin University,5333 Xi'an Road,Changchun,130062, Jilin,China.
J Dairy Res. 2016 Nov;83(4):442-446. doi: 10.1017/S0022029916000546. Epub 2016 Oct 3.
Dairy cows with fatty liver or ketosis exhibit hyperketonemia, oxidative stress, and a low rate of very low density lipoprotein (VLDL) assembly, and there may be a potential link among these characteristics. Therefore, the objective of this study was to determine the effect of acetoacetic acid (AcAc) on the assembly of VLDL in cow hepatocytes. Cultured cow hepatocytes were treated with different concentrations of AcAc with or without N-acetylcysteine (NAC, an antioxidant). AcAc treatment decreased the mRNA expression and activities of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px), and significantly increased malondialdehyde (MDA) content, indicative of oxidative stress. Furthermore, AcAc treatment significantly down-regulated the mRNA expression of apolipoprotein B100 (ApoB100), apolipoprotein E (ApoE), and low density lipoprotein receptor (LDLR), which thus decreased VLDL assembly and increased triglyceride (TG) accumulation in these bovine hepatocytes. Importantly, NAC relieved AcAc-induced oxidative stress and increased VLDL assembly. In summary, these results suggest that AcAc-induced oxidative stress affects the assembly of VLDL, which increases TG accumulation in bovine hepatocytes.
患有脂肪肝或酮病的奶牛表现出高酮血症、氧化应激以及极低密度脂蛋白（VLDL）组装率低下，并且这些特征之间可能存在潜在联系。因此，本研究的目的是确定乙酰乙酸（AcAc）对奶牛肝细胞中VLDL组装的影响。用不同浓度的AcAc处理培养的奶牛肝细胞，同时添加或不添加N-乙酰半胱氨酸（NAC，一种抗氧化剂）。AcAc处理降低了抗氧化酶超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和谷胱甘肽过氧化物酶（GSH-Px）的mRNA表达和活性，并显著增加了丙二醛（MDA）含量，表明存在氧化应激。此外，AcAc处理显著下调了载脂蛋白B100（ApoB100）、载脂蛋白E（ApoE）和低密度脂蛋白受体（LDLR）的mRNA表达，从而减少了这些牛肝细胞中的VLDL组装并增加了甘油三酯（TG）积累。重要的是，NAC减轻了AcAc诱导的氧化应激并增加了VLDL组装。总之，这些结果表明，AcAc诱导的氧化应激影响VLDL的组装，这增加了牛肝细胞中的TG积累。
