Mibefradil通过下调FoxO1表达改善HepG2细胞的胰岛素抵抗  

Mibefradil improves insulin-resistance HepG2 cells by down-regulating FoxO1 expression

作　　者：马欢 严军[2] 张克斌[3] 徐梓辉[4] MA Huan YAN Jun ZHANG Kebin XU Zihui(Department of Endocrinology 3Laboratory Cente 4Department of Integrated Chinese and Western Medicine, Xinqiao Hospital, Third Military Medical University, Chongqing, 400037 2State Key Laboratory of Trauma, Burns and Combined Injury, Department 1, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, 400042, China)

机构地区：[1]第三军医大学新桥医院内分泌科,重庆400037 [2]第三军医大学大坪医院野战外科研究所第一研究室,创伤,烧伤与复合伤国家重点实验室,重庆400042 [3]第三军医大学新桥医院中心实验室,重庆400037 [4]第三军医大学新桥医院中西医结合科,重庆400037

出　　处：《第三军医大学学报》2017年第20期1973-1979,共7页Journal of Third Military Medical University

基　　金：国家自然科学基金面上项目(81570781)~~

摘　　要：目的探索Mibefradil在体外对胰岛素抵抗HepG2细胞的作用。方法将HepG2细胞分为对照组、棕榈酸盐(Palmitate,PA)诱导的HepG2细胞胰岛素抵抗模型组、药物溶剂(DMSO)组、低剂量(0.025μmol/L)Mibefradil组、高剂量(0.05μmol/L)Mibefradil组,通过检测各组糖原合成及葡萄糖消耗,观察Mibefradil对胰岛素抵抗HepG2细胞的改善作用。用qRT-PCR、Western blot检测各组Fox O1,糖异生、糖原分解限速酶,即:磷酸烯醇式丙酮酸羧基激酶(PEPCK)、葡萄糖-6-磷酸激酶(G6Pase)的mRNA、蛋白相对表达量,明确转录因子Fox O1及其靶基因的表达水平。结果相比于对照组,HepG2细胞胰岛素抵抗模型组的糖原合成量[(3.28±0.74)μg/μL vs(9.14±0.33)μg/μL,P<0.01]及葡萄糖消耗量[(1.31±0.49)nmol/μg vs(5.87±2.26)nmol/μg,P<0.01]明显下降;经Mibefradil干预后,胰岛素抵抗HepG2细胞的糖原合成及葡萄糖消耗得到明显改善,且高剂量组的糖原合成[(7.09±0.60)μg/μL vs(5.73±0.16)μg/μL,P<0.01)]及葡萄糖消耗[(6.45±0.02)nmol/μg vs(5.61±0.29)nmol/μg,P<0.01]显著高于低剂量组,表明Mibefradil可改善HepG2细胞的胰岛素抵抗。qRT-PCR及Western blot检测结果表明,胰岛素抵抗HepG2细胞的Fox O1、PEPCK、G6Pase的表达量均显著增加(P<0.01);经Mibefradil干预后,其表达量呈剂量依赖性下降(P<0.05)。结论Mibefradil对胰岛素抵抗HepG2细胞具有改善作用,此作用可能与下调Fox O1的表达有关。To explore the ameliorative effect of Mibefradil on the insulin resistance model of HepG2 cells in vitro. Methods HepG2 cells were randomly divided into 5 groups, that is, control group, insulin resistance model group （induced by 0.25 mmol/L palmitate）, DMSO model group, low-dosage Mibefradil treatment group （0.025 μmol/L）, and high-dosage Mibefradil treatment group （0.05 μmol/L）. And all groups were disposed with corresponding drugs according to the above mentioned for 24 h. Glycogen synthesis and glucose consumption of HepG2 cells of each group were detected to observe treatment effects of Mibefradil. Quantitative real-time PCR （qRT-PCR） and Western blotting were used to detect the expression levels of FoxO1 and limited enzymes of gluconeogenesis and glycogenolysis, that is, phosphoenolpyruvate carboxykinase （PEPCK） and glucose-6-phosphatase （G6Pase）, which are the target genes of FoxO1. Results Compared with control group, the model group had significantly decreased glycogen synthesis （3.28±0.74 vs 9.14±0.33 μg/μL, P〈0.01） and glucose consumption （1.31±0.49 vs 5.87±2.26 nmol/μg, P〈0.01）. Mibefradil treatment obviously improved glycogen synthesis and glucose consumption in the HepG2 cells of insulin resistance model, with the highdosage Mibefradil group more significant than the low-dosage one （7.09±0.60 vs 5.73±0.16 μg/μL, P〈0.01; 6.45±0.02 vs 5.61±0.29 nmol/μg, P〈0.01）. qRT-PCR and Western blotting indicated that the expression levels of FoxO1, PEPCK and G6Pase were remarkably increased in the HepG2 cells of insulin resistance model, however Mibefradil treatment would decrease the levels in a dose-dependent manner （P〈0.05）. Conclusion Mibefradil relieves the insulin resistance of HepG2 cells via decreasing the expression of FoxO1 .

关 键 词：MIBEFRADIL 胰岛素抵抗 HEPG2细胞 FOXO1 

分 类 号：R458.5[医药卫生—治疗学] R735.7[医药卫生—临床医学]