奶牛CCT-α基因调控肝脏细胞脂滴大小的机制研究  

Study on the Mechanism of CCT-αGene Regulating Lipid Droplet Size in Bovine Hepatocytes Cells

作　　者：吴奎显 范雨欣 李琪玉 倪晗 高古睿 杨玉 闫丽萍 郭爽[1] 杨彦宾 刘洋[1] 韩立强[1] WU Kuixian;FAN Yuxin;LI Qiyu;NI Han;GAO Gurui;YANG Yu;YAN Liping;GUO Shuang;YANG Yanbin;LIU Yang;HAN Liqiang(Henan Key Laboratory of Veterinary Biotechnology,College of Veterinary Medicine,Henan Agricultural University,Zhengzhou,Henan 450046,China)

机构地区：[1]河南农业大学动物医学院,河南省兽医生物技术重点实验室,河南郑州450046

出　　处：《中国牛业科学》2025年第1期4-9,共6页China Cattle Science

基　　金：河南省杰出青年科学基金(242300421029);河南省重点研发专项(231111111400)。

摘　　要：围产期奶牛肝脏细胞中脂滴的异常积累会导致奶牛产生脂肪肝。磷酸胆碱胞苷酸转移酶-α(CCT-α)是CDP胆碱途径中的一个重要限速酶,其对奶牛肝脏细胞中脂滴生成的调控作用还不清楚。本试验通过研究CCT-α敲除(CCT-KO)及过表达(CCT-OE)奶牛的肝脏细胞系,采用脂滴油红染色法检测细胞中脂滴的大小及数量变化,薄层色谱法分析细胞中磷脂酰胆碱(PC)的含量,通过Western blot检测对自噬蛋白的影响。结果表明,对照组正常奶牛肝脏细胞中脂滴直径为1.51μm,CCT-KO组细胞中脂滴直径增大到2.29μm,CCT-OE组脂滴直径减小为1.27μm。分析脂滴数量发现,CCT-α基因敲除使脂滴数量显著减少,而CCT-α基因过表达则使脂滴数量明显增加(P<0.05)。CCT-KO组细胞中PC含量减少,而CCT-OE组的PC含量显著增加。蛋白表达分析发现,CCT-KO组中LC3-Ⅱ/LC3-Ⅰ之比较对照下降了18.9%,p62蛋白表达量上调了19.1%;而CCT-OE组中LC3-Ⅱ/LC3-Ⅰ之比较对照上升了35.7%,p62蛋白表达量下调了31.2%。以上结果说明奶牛CCT-α基因能够通过影响肝脏细胞磷脂含量和自噬来调控脂滴大小,为阐明奶牛脂肪肝的发病机制奠定了基础。Accumulation of lipid droplets in the hepatocytes during the perinatal period leads to fatty liver in dairy cows.Phosphocholine cytidylyltransferase-alpha(CCT-α)is an important rate-limiting enzyme in CDP’s choline pathway,and its role in regulating lipid accumulation is unclear in bovine hepatocytes.In this experiment,CCT-αknockout(CCT-KO)and overexpressed(CCT-OE)hepatocyte lines of bovine were studied,and oil red staining was used to detect the size and quantity of lipid droplets(LDs)in cells.The content of phosphatidylcholine(PC)was analyzed by TLC and the expression of autophagy protein was detected by Western blot.The results showed that the diameter of LDs in bovine hepatocytes of the control group was 1.51μm,the diameter of LDs in the CCT-KO group was increased to 2.29μm,and the diameter in the CCT-OE group was decreased to 1.27μm.CCT-αgene knockout significantly reduced the number of lipid droplets,while CCT-αgene overexpression significantly increased the number of lipid droplets(P<0.05).The content of phosphatidylcholine(PC)in CCT-KO group was decreased,while that of CCT-OE group was significantly increased.Compared with control group,the ratio of LC3-Ⅱ/LC3-Ⅰprotein in CCT-KO group was decreased by 18.9%and p62 protein was up-regulated by 19.1%,while the ratio of LC3-Ⅱ/LC3-Ⅰwas increased by 35.7%,and the expression of p62 protein was down-regulated by 31.2%in CCT-OE group.These results indicate that the CCT-αgene regulates LD size by influencing the synthesis of cytophospholipids and autophagy,which lays a foundation for illustrating the mechanism of fatty liver in dairy cows.

关 键 词：奶牛 肝脏细胞 CCT-α 磷脂酰胆碱 自噬 

分 类 号：S823.1[农业科学—畜牧学]