分泌型卷曲相关蛋白/β-联蛋白信号通路对脂肪形成的影响  

Effect of secreted frizzled-related protein 5/β-catenin signalling pathway in adipogenesis

作　　者：王睿[1] 王计秋[1] 刘瑞欣[1] 陈茂培[1] 洪洁[1] 王卫庆[1] 宁光[1] 

机构地区：[1]上海交通大学医学院附属瑞金医院内分泌代谢病科,上海200025

出　　处：《内科理论与实践》2013年第1期34-38,共5页Journal of Internal Medicine Concepts & Practice

基　　金：国家自然科学基金(项目编号:81270931)

摘　　要：目的:探讨分泌型卷曲相关蛋白(sFRP5)和经典Wnt信号通路在脂肪细胞形成中的作用及机制。方法:诱导3T3-L1前体脂肪细胞分化,用过表达sFRP5的携带绿色荧光蛋白基因的重组腺病毒(Ad-sFRP5-GFP)感染3T3-L1细胞并诱导成熟,利用实时荧光定量PCR检测经典Wnt下游靶基因和脂肪分化相关基因mRNA水平的变化。3T3-L1细胞分化成熟后,进行油红染色,观察过表达sFRP5对脂滴形成的影响;提取核浆蛋白,用蛋白质印迹法检测sFRP5对β-联蛋白核转位的影响。结果:3T3-L1细胞分化成熟后期,sFRP5、CCAAT增强子结合蛋白α(C/EBPα)、过氧化物酶体增殖物活化受体γ2(PPARγ2)表达均显著增加,同时,细胞周期蛋白D1表达显著下调。而诱导分化成熟后,过表达sFRP5的3T3-L1细胞周期蛋白D1无显著改变。与空载对照组相比,过表达sFRP5的3T3-L1细胞脂滴形成无明显变化。给予3T3-L1细胞重组小鼠sFRP5直接刺激或感染Ad-sFRP5-GFP,均未明显改变β-联蛋白核转位。结论:sFRP5的表达随着脂肪细胞分化而显著增加,但不影响体外脂肪细胞分化,sFRP5在体外不直接通过拮抗Wnt/β-联信号通路的方式发挥作用。Objective To investigate the effect and mechanism of secreted frizzled-related protein 5 （sFRPS）/β- catenin signalling pathway in the course of adipogenesis. Methods 3T3-L1 preadipocytes were induced under standard differentiation process. Adenoviral vectors overexpressing sFRP5 （Ad-sFRPS-GFP） were constructed and infected into 3T3- L1 preadipocytes. Levels of Wnt targeted and adipogenesis-associated genes in the course of differentiation were measured by real-time PCR. The lipid droplets of maturely differentiated 3T3-L1 cells were observed by oil-red O staining. The β- catenin translocation to nucleus of 3T3-L1 cells was detected by Western blot. Results The expression of sFRP5 was increased during 3T3-L1 cells differentiation, along with the up-regulation of adipoeyte differentiation-associated gene expression including CCAAT/ enhancer binding protein α （C/EBPot） and peroxisome proliferator-activated receptor γ 2 （PPAR72）, as well as the down-regulation of cyclin D1. However, no dramatic change of cyclin D1 mRNA level was found in 3T3-L1 cells overexpressing sFRP5. No significant changes were found in lipid droplets in 3T3-L1 preadipocytes overexpressing sFRP5 or in the course of β-catenin translocation to nucleus of 3T3-L1 preadipocytes overexpressing sFRP5 as well as treated with recombined mouse sFRP5 protein. Conclusions SFRP5 is associated with adipogenesis but has no effect on adipocyte differentiation. There is no interaction between sFRP5 and Wntβ-eatenin signalling pathway.

关 键 词：分泌型卷曲相关蛋白 β-联蛋白 肥胖症 脂肪形成 脂肪细胞分化 

分 类 号：R589.2[医药卫生—内分泌]