大黄素激活AMPK／SREBP-1通路减少脂肪酸诱导的HepG2细胞脂肪变性  

Emodin reduces FFAs-induced fatty degeneration in HepG2 cells via the AMPK/SREBP-1 pathway

作　　者：徐轶玲 王国栋[1] 刘波[1] 余波[1] 黄齐飞[1] 苏秀媛 刘慧霞[1] 

机构地区：[1]中南大学湘雅医院老年病科,长沙410008

出　　处：《中国医师杂志》2017年第4期506-509,513,共5页Journal of Chinese Physician

基　　金：国家自然科学基金（81500692）

摘　　要：目的研究大黄素对游离脂肪酸（FFAs）诱导的人源肝癌细胞HepG2细胞脂质蓄积的脂质调节和氧化应激作用及其可能的相关机制。方法以噻唑蓝（MTT）法测定大黄素对HepG2细胞存活率的影响；采用1mmol／IJFFAs（油酸：棕榈酸=2：1）诱导HepG2细胞脂肪变性，将HepG2细胞分为5组：正常对照组、模型组、大黄素低剂量组、大黄素中剂量组、大黄素高剂量组。采用油红O染色及甘油三酯含量测定评价大黄素对肝细胞脂肪变性程度的影响。流式细胞术检测各组细胞脂质蓄积引起的活性氧（ROS）的变化；WesternNot检测各组细胞单磷酸腺苷活化蛋白激酶（AMPK）、磷酸化AMPK（p-AMPK）、固醇调节元件蛋白1（SREBP-1）的表达变化。结果1mmol／LFFAs处理后的HepG2细胞24h后出现大量脂滴，TG含量明显增加（P〈0．05）。与模型组相比，大黄素组的脂滴减少，甘油三酯蓄积下降（P〈0．05），并呈剂量依赖性；还可以降低脂肪酸氧化后的ROS水平（P〈0．01）。另外，大黄素处理后增加AMPK与p-AMPK的表达水平（P〈0．01），下调SREBP-1的表达水平（P〈0．01）。结论大黄素可抑制FFAs诱导的HepG2细胞脂肪蓄积，减轻氧化应激损伤，其作用可能与激活AMPK／SREBP-1通路有关。Objective To investigate the effects of emodin on the triglyceride metabolism and oxi- dative stress in steatosis in HepG2 cells and possible underlying mechanisms. Methods The appropriate concentration of emodin on HepG2 cells were detected by methyl thiazolyl tetrazolium （MTT） assay. HepG2 cells were induced to fat overaccumulation by 1 mmol/L free fatty acids （FFA） （oleate： palmitate = 2：1 ）. The model group exposed to 10 μmol/L, 20 μmol/L, 40 μmol/L emodin. The intracellular lipid accumula- tion was documented by Oil Red O staining and the content of triglyceride and total cholesterol was ob- served. Reactive oxygen species （ROS） was determined by flow cytometry. Western blotting was performed to analyze the protein levels of adenosine monophosphate-activated protein kinase （AMPK） , phosphorylated AMPK, and sterol regulatory element-binding protein 1 （ SREBP-1 ）. Results Emodin reduced lipid accu- mulation and triglycerides （TG） content （P 〈0. 05）. At the same time, it significantly reduced ROS pro- duction （ P 〈 O. 05）. Moreover, the levels of AMPK and p-AMPK protein were significantly upregulated, and SREBP-I protein was significantly downregulated with the treatment of emodin （ P 〈 0. 01 ）. Conclu- sions This study has demonstrated that emodin can reduce fatty degeneration induced by FFAs in hepato- cytes, and this effect may be partially mediated by the AMPK/SREBP-1 pathway.

关 键 词：大黄素/药理学 肝肿瘤 脂肪酸类/副作用 胆固醇调节元件结合蛋白质1 蛋白激酶类 脂类 氧化性应激 

分 类 号：R285[医药卫生—中药学]