miR-320a-5p对高脂饮食诱导的小鼠肥胖和IR的影响研究  

Study on the effect of miR-320a-5p in high fat diet-induced obese and IR in mice

作　　者：胡淑芳[1] 杨丽[1] 蔡桃英 徐子辉 HU Shufang;YANG Li;CAI Taoying;XU Zihui(Department of Endocrinology,Hankou Hospital of Wuhan City,Wuhan,Hubei 430012,China;Department of Endocrinology,Renmin Hospital of Wuhan University,Wuhan,Hubei 430060,China)

机构地区：[1]湖北省武汉市汉口医院内分泌科,430012 [2]武汉大学人民医院内分泌科,武汉430060

出　　处：《重庆医学》2020年第16期2605-2611,2616,共8页Chongqing medicine

基　　金：国家自然科学基金青年项目(31400916);湖北省武汉市卫生和计划生育委员会科研项目(WX15D39,WZ16C22)。

摘　　要：目的探讨miR-320a-5p对高脂饮食(HFD)诱导的小鼠肥胖和胰岛素抵抗(IR)的影响。方法45只雄性C57BL/6小鼠分为对照(ND)组、HFD组和mmu-miR-320a-5p agomir(MA)组。以HFD喂养8周后,HFD组尾静脉注射20 nmol/L的miRNA激动剂的阴性对照(micrONTM miRNA agomir NC)的100μL磷酸盐缓冲液,MA组注射等量mmu-miR-320a-5p agomir,直至20周。期间监测小鼠体重变化,分析3组小鼠20周腰围、代谢水平、胰岛素耐受实验(IPTT)、口服糖耐量实验(OGTT)情况;苏木素-伊红(HE)染色检测脂肪组织形态学变化;实时荧光定量PCR(RT-qPCR)检测各组外周血和脂肪组织miR-320a-5p相对表达水平及Pparg、Ppara、Cebpa、Cebpb基因mRNA表达水平;ELISA检测外周血胰岛素样生长因子-1(Igf-1)水平;Western blot检测脂肪组织Igf-1、Phospho-Igf-1-rβ/Irβ(Tyr1131/1146)、Phospho-Irs1(Tyr1222)、Phospho-Gsk3(Ser9)、Phospho-PI3K p85/p55(Tyr458/199)、Phospho-Akt(Thr308)、phospho-FoxO1(Ser256)、Ppar-γ、Gck、G6Pase和Pepkc蛋白表达水平。结果与HFD组比较,MA组小鼠的腰围、内脏脂肪组织(eWAT)湿重、胰岛素水平和胰岛素抵抗指数(HOMA-IR)更低,体温热量输出值、呼吸熵、糖耐量、血糖清除速率和eWAT中miR-320a-5p水平更高,差异有统计学意义(P<0.05)。与HFD组比较,MA组外周血Igf-1水平,eWAT中Igf-1、Phospho-Igf-1-rβ/Irβ(Tyr1131/1146)、Phospho-Irs1(Tyr1222)、Phospho-Gsk3β(Ser9)、Phospho-PI3K p85/p55(Tyr458/199)、Phospho-Akt(Thr308)、Gck、G6Pase和Pepck蛋白及Pparg、Ppara、Cebpa和Cebpb基因mRNA水平更低,Phospho-FoxO1(Ser256)水平更高,差异有统计学意义(P<0.05)。结论上调miR-320a-5p可抑制HFD小鼠的肥胖和IR。Objective To investigate the effect of miR-320a-5p on high fat diet(HFD)-induced obese and insulin resistance(IR)in mice.Methods A total of 45 male C57BL/6 mice were divided into the control group(the ND group),the HFD group and the mmu-miR-320a-5p agomir group(the MA group).After being fed with HFD for 8 weeks,the HFD group was injected with 20 nmol/L miRNA agonist negative control(micrONTM miRNA agomir NC)in 100μL of PBS,and the MA group was injected with the same amount of mmu-miR-320a-5p agomir until 20 weeks.The body weight was monitored,and the waist circumference,metabolism,insulin tolerance test(IPTT)and oral glucose tolerance test(OGTT)were analyzed for the three groups during the experiment.The morphology of adipose tissue were detected by hematoxylin-eosin(HE)staining.MiR-320a-5p in peripheral blood,the mRNA levels of Pparg,Cebpa,Cebpb and Ppara in adipose tissue were detected by RT-qPCR.Insulin-like growth factor-1(Igf-1)level in peripheral blood was detected by ELISA assay.Western blot was used to detect the protein expression levels of Igf-1,Phospho-Igf-1-rβ/Irβ(Tyr1131/1146),Phospho-Irs1(Tyr1222),Phospho-Gsk3(Ser9),Phospho-PI3K p85/p55(Tyr458/199),Phospho-Akt(Thr308),phospho-FoxO1(Ser256),Ppar-γ,Gck,G6Pase and Pepkc in adipose tissue.Results Comparedwith the HFD group,waist circumference,epididymal white adipose tissue(eWAT)wet weight,insulin content,homeostasis model assessment-insulin resistance(HOMA-IR)in the MA group were lower;while energy expenditure,respiratory exchange rate,glucose tolerance,blood glucose clearance rate and eWAT miR-320a-5p content were higher,the difference was statistically significant(P<0.05).Besides,compared with the HFD group,Igf-1 level in peripheral blood,the protein levels of Igf-1,Phospho-Igf-1-rβ/Irβ(Tyr1131/1146),Phospho-Irs1(Tyr1222),Phospho-Gsk3β(Ser9),Phospho-PI3K p85/p55(Tyr458/199),Phospho-Akt(Thr308),Gck,G6Pase,Pepck and the mRNA levels of Pparg,Ppara,Cebpa,Cebpb in eWAT were lower in the MA group,while Phospho-FoxO1(Ser256)was higher,the difference

关 键 词：肥胖症 脂细胞 细胞增殖 胰岛素样生长因子Ⅰ 磷酸肌醇3-激酶类 蛋白质丝氨酸苏氨酸激酶 微RNAS miR-320a-5p 胰岛素抵抗 

分 类 号：R589.2[医药卫生—内分泌]