miR-141与2型糖尿病大鼠血糖水平的关系及其作用机制研究

Relationship between miR-141 and blood glucose levels in rats with type 2 diabetes and its mechanism

目的探讨miR-141与T2DM大鼠血糖水平关系及其对蛋白激酶B(Akt)/AMP依赖的蛋白激酶α(AMPKα)通路和炎症因子释放的影响.方法将SD大鼠随机分为对照组(Con)、糖尿病组(DM)、糖尿病+miR-141抑制剂组[miR-141(-)]及糖尿病+miR-141模拟物组[miR-141(+)].RT-PCR检测IRS2、miR-141、核因子κB p65(NF-κBp65)表达,Western blot检测Akt/AMPKα蛋白表达.结果与DM组比较,miR-141(-)组各时间点血糖水平、FPG、TNF-α、IL-1β及高级氧化蛋白产物(AOPPs)降低,miR-141(+)组上述指标升高(P<0.05或P<0.01).与DM组比较,miR-141(-)组胰岛细胞凋亡降低,miR-141(+)组升高(P<0.05或P<0.01).与DM组比较,miR-141(-)组miR-141、NF-κBp65 mRNA、NF-κBp65蛋白表达降低(P<0.05),IRS2 mRNA、p-Akt、p-AMPKα、IRS2升高(P<0.05或P<0.01),miR-141(+)组NF-κBp65蛋白表达升高(P<0.01).结论miR-141高表达导致T2DM大鼠血糖水平升高、IRS2降低,其作用机制可能与Akt/AMPKα通路蛋白磷酸化被抑制进而导致的炎症反应有关.

Objective To investigate the relationship between miR-141 and blood glucose levels in rats with type 2 diabetes and its effects on Akt/AMPKα pathway and inflammatory factor release.Methods SD rats were randomly divided into control group(Con),diabetes group(DM),miR-141 inhibitor+diabetes group [miR-141(-)]and miR-141 mimic+diabetes group[miR-141(+)].The expression of IRS2,miR-141 and NF-KBp65 were detected by RT-PCR,and the expression of Akt/AMPKα protein was detected by western blot.Results PG level,FPG,TNF-α,IL-1β and AOPPs were significantly lower in miR-141(-)group than in DM group(P<0.05 or P<0.01),while significantly higher in miR-141(+)group than in DM group(P<0.05 or P<0.01).Islet cell apoptosis was lower in miR-141(-)group than in DM group,while higher in miR-141(+)group than in DM group(F<0.05 or P<0.01).The miR-141,NF-kBp65 and NF-KBp65 mRNA were lower in miR-141(-)group than in DM group(F<0.05).IRS2 mRNA,p-Akt,p-AMPKα.IRS2 were higher in miR-141(-)group than in DM group(P<0.05 or P<0.01).NF-kBp65 protein experssion were rose in miR-141(+)group(P<0.01).Conclusion High expression of miR-141 leads to elevated blood glucose and decreased IRS2 level in type 2 diabetic rats,which may be related to phosphorylation of Akt/AMPKα pathway and the relevant inflammatory responses.