吉林大学学报(医学版) ›› 2016, Vol. 42 ›› Issue (05): 905-909.doi: 10.13481/j.1671-587x.20160513

• 基础研究 • 上一篇    下一篇

miR-221对糖尿病肾病小鼠胰岛β细胞功能的保护作用及其机制

李俊, 代留玲, 李晔, 茶春丽   

  1. 昆明医科大学第一附属医院肾内科, 云南 昆明 650032
  • 收稿日期:2015-09-17 出版日期:2016-09-28 发布日期:2016-09-29
  • 通讯作者: 李俊,主任医师,硕士研究生导师(Tel:0871-65324888-2528,E-mail:dllijun1968@163.com) E-mail:dllijun1968@163.com
  • 作者简介:李俊(1968-),女,白族,云南省大理市人,主任医师,医学硕士,主要从事肾纤维化临床与基础方面的研究。
  • 基金资助:

    云南省科技厅应用基础研究计划项目资助课题(2012FB029);云南省教育厅资助项目资助课题(2014J040)

Protective effect of miR-221 on β cells in mice with diabetic nephropathy and its mechanism

LIJun, DAILiuling, LI Ye, CHA Chunli   

  1. Department of Internal Medicine, First Affiliated Hospital, Kunming Medical University, Kunming 650032, China
  • Received:2015-09-17 Online:2016-09-28 Published:2016-09-29

摘要:

目的:研究miR-221对糖尿病肾病(DN)小鼠胰岛β细胞功能的影响,阐明miR-221在DN中的保护作用机制。方法:8周龄野生型雄性C57BL/6J小鼠20只随机分成对照组和DN组,每组10只,对照组小鼠给予正常饮食,DN组小鼠给予高脂饮食,并注射100 mg·kg-1链脲佐菌素(STZ)诱导部分胰岛素缺陷,对照组小鼠注射同体积柠檬酸缓冲液。之后DN组继续给予高脂饮食,对照组给予正常饮食,饲养10周后收集小鼠血液和尿液,检测血糖、血肌酐、血尿素氮浓度和24 h尿白蛋白排泄率等生理参数。在DN组小鼠中分离得到胰岛细胞。利用Real-time PCR检测胰岛细胞中SOCS3 mRNA表达水平,采用MTT法检测胰岛细胞增殖情况,ELISA法检测胰岛细胞中胰岛素含量和胰岛素的释放水平,荧光素酶报告基因法检测SOCS3活性荧光酶素报告基因活性。结果:成功构建DN小鼠模型。DN组小鼠的血糖、血肌酐、血尿素氮浓度和24h尿白蛋白排泄率均高于对照组(P<0.05)。过表达miR-221后,DN组小鼠胰岛细胞中SOCS3 mRNA表达水平低于正常胰岛细胞(P<0.05),过表达miR-221后胰岛细胞的增殖能力低于正常胰岛细胞(P<0.05),荧光素酶报告基因法确定SOCS3为miR-221下游靶基因。过表达miR-221后,胰岛细胞中胰岛素质量分数和胰岛素释放水平均高于正常胰岛细胞(P<0.05)。结论:miR-221通过下调SOCS3水平促进胰岛细胞合成和分泌胰岛素的功能,改善DN小鼠中胰岛细胞的功能障碍。

关键词: 糖尿病肾病, miR-221, 细胞因子信号抑制因子 3, 胰岛&beta, 细胞

Abstract:

Objective: To study the influence of miR-221 in the β cells of mice with diabetic nephropathy (DN), and to clarify the protective effect of miR-221 on DN. Methods: Twenty wild type C57BL/6J mice aged 8 weeks were divided into control group and DN group(n=10).The DN mice models were constructed with 14 weeks of high fat diet,and 100mg·kg-1 streptozotocin (STZ) was used to induce the partial insulin deficiency. 10 weeks later the blood glucose, serum creatinine, blood urea nitrogen content and 24h-urinary albumin excretion rate were detected. The β cells of islet were isolated from the DN mice. The expression level of SOCS3 mRNA in β cells of islet was valued by Real-time PCR. The proliferation of pancreatic β cells of islet was examined by MTT assay. The contents of insulin and insulin release levels in pancreatic β cells of islet were detected by ELISA assay. Luciferase reporter gene assay was used to detect the luciferase reporter gene activity of SOCS3. Results: The DN mouse models were constructed successfully. The blood glucose, serum creatinine, blood urea nitrogen and 24h-urinary albumin excretion rate of the mice in DNA group were higher than those in control group(P<0.05). After overexpression of miR-221, the expression level of SOCS3 mRNA in pancreatic β cells of islet and the proliferation ability of β cells of islet of the mice in DN group were lower than those of normal islet cells (P<0.05). Then luciferase reporter gene method found SOCS3 as one of the target genes of miR-221. After overexpression of miR-221, the insulin release level and insulin content in pancreatic β cells of islet were higher than those of normal islet cells(P<0.05). Conclusion: miR-221 can promopt the synthesis and secretion of β cells of islet and inhibit the dysfunction of β cells of islet in the DN mice by down-regulating the SOCS3 level.

Key words: diabetic nephropathy, miR-221, suppressor of cytokine signaling 3, &beta, cells of islet

中图分类号: 

  • R587.1