胆固醇过负荷对脂肪细胞分泌内脂素的影响及其机制  

Effects of cholesterol overload on visfatin secretion from adipocytes and the mechanism

作　　者：陈名杰[1] 吴智鸿[1] 陈雅琴[1] 龚海荣[1] 李向平[1] 

机构地区：[1]中南大学湘雅二医院心血管内科,长沙410011

出　　处：《中华内分泌代谢杂志》2012年第2期153-156,共4页Chinese Journal of Endocrinology and Metabolism

基　　金：国家自然科学基金（30900624）;教育部博士点新教师基金项目（200805331005）

摘　　要：3T3-L1细胞促分化成熟后,分别以酯酰辅酶A胆固醇酯酰转移酶（ACAT）抑制剂（2μg/ml）和不同浓度（0、25、50、75和100 μg/ml）的氧化型低密度脂蛋白（ox-LDL）干预48 h,ACAT抑制剂（2μg/ml）和ox-LDL（ 50 μg/ml）干预0、6、18、36和48 h,ACAT抑制剂（2μg/ml）、ox-LDL（ 50 μg/ml）和不同浓度（0、100、200和400 μmol/L）的牛磺酸熊去氧胆酸（TUDCA）干预48 h.用ELISA法检测细胞上清内脂素的水平,Western印迹法检测脂肪细胞总蛋白GRP78和CHOP表达.ACAT抑制剂和不同浓度的ox-LDL干预脂肪细胞48 h后,随着ox-LDL浓度的增加,脂肪细胞内胆固醇浓度、GRP78和CHOP蛋白表达及内脂素水平显著升高,实验组与空白对照组比较,差异均具有统计学意义（均P＜0.05）；ACAT抑制剂和ox-LDL干预后,随干预时间的延长,脂肪细胞GRP78、CHOP蛋白表达及内脂素水平均显著升高,实验组与空白对照组比较,差异均有统计学意义（均P＜0.05）；ACAT抑制剂、ox-LDL和不同浓度TUDCA干预48 h后,脂肪细胞GRP78及CHOP蛋白表达水平及内脂素水平逐渐降低,实验组（200和400 μmol/L）与空白对照组比较,差异均有统计学意义（均P＜0.05）.脂肪细胞胆固醇负荷增加可促进脂肪细胞分泌内脂素,其机制可能与脂肪细胞的内质网应激增强有关.3T3-L1 adipocytes were cultured and differentiated into mature adipocytes in vitro. The adipocytes were intervened by ACAT inhibitor（ 2 μg/ml） and ox-LDL with various concentrations （0,25,50,75,and 100 μg/ml）for 48 h,ACAT inhibitor（ 2 μg/ml） and ox-LDL（ 50 μg/ml） at the 0,6,18,36,and 48 h,or ACAT inhibitor（ 2 μg/ml）,ox-LDL（ 50 μg/ml）,and TUDCA with various concentrations（0,100,200,and 400 μ mol/L）for 48 h,respectively.The levels of visfatin in supernatant were examined by ELISA and the expressions of protein GRP78 and CHOP in adipocytes were detected by Western blot.After the adipocytes were treated with ACAT inhibitor and ox-LDL at different concentrations for 48 h,the cholesterol concentration and the expressions of GRP78 and CHOP protein in adipocytes and the visfatin levels in the supernatant fluid were increased with the increase of the ox-LDL concentration.The differences had statistical significance in the experimental groups compared with blank control group（ all P〈0.05 ）.After the intervention with ACAT inhibitor and ox-LDL for different durations,the expressions of GRP78 and CHOP protein in adipocytes and the visfatin levels in the supernatant fluid were up-regulated in a timedependent manner.The differences between experimental groups and blank control had statistical significance（ all P〈0.05 ）.After the intervention with ACAT inhibitor,ox-LDL,and different concentrations of TUDCA for 48 hours,the expressions of GRP78 and CHOP protein in adipocytes and visfatin levels in the supernatant fluid were down-regulated in a dose-dependent manner and as compared with blank control group the difference were statistically significant（ all P〈 0.05 ）.The increase of cholesterol load in adipocyte may promote the visfatin secretion,denoting that the mechanism might be due to the enhancement of endoplasmic reticulum stress in aidpocytes.

关 键 词：胆固醇 内脂素 内质网应激 脂肪细胞 

分 类 号：R329[医药卫生—人体解剖和组织胚胎学]