内脂素在糖尿病大鼠肝组织的表达及其对肝糖代谢的作用

The expression of visfatin in liver of diabetic rats and it′s relationship with type 2 diabetic

目的检测糖尿病大鼠肝组织内脂素(visfatin)的表达,探讨内脂素在肝糖代谢的作用。方法雄性SD大鼠,分为5组:正常对照组(NC组)、肥胖组(DIO组)、糖尿病组(DM组)、胰岛素治疗组(INS组)、二甲双胍治疗组(MET组)。检测大鼠空腹血糖(FPG)、总胆固醇(TC)、三酰甘油(TG)、游离脂肪酸(FFA)、空腹胰岛素(Fins)水平;RT-PCR测定大鼠肝组织visfatin、葡萄糖6磷酸酶(G-6-Pase)mRNA的水平,Western blot检测visfatin、磷酸化腺苷酸活化蛋白激酶-α(p-AMPKα)和腺苷酸活化蛋白激酶-α(AMPKα)蛋白表达量。结果 DM组FBG较NC组、DIO组均显著升高(P<0.01);INS组、MET组FBG较DM组显著下降(P<0.01)。DIO组、DM组HOMA-IR均较NC组显著升高(P<0.01);DM组HOMA-IR较DIO组显著升高(P<0.01)。DIO组、DM组ISI均较NC显著降低(P<0.01),DM组ISI较DIO组显著降低(P<0.01)。DIO组TG较NC组显著升高(P<0.01);INS组、MET组TG较DM组显著降低(P<0.05),DM组、INS组、MET组TG、TC均较NC组升高(P<0.05)。DM组、MET组、INS组FFA均较NC组明显升高(P<0.05);DM组FFA较DIO组明显升高(P<0.05)。DM组visfatin mRNA表达较NC组、DIO组显著升高(P<0.05);INS组、MET组visfatin mRNA较DM组显著降低(P<0.01)。DM组、MET、INS组G-6-Pase mRNA较DIO组显著升高(P<0.05),MET组G-6-Pase mRNA较DM组显著降低(P<0.05)。DM组、INS组、MET组visfatin蛋白表达较NC组显著升高(P<0.05);DM组、MET组、INS组AMPKα蛋白表达较NC组显著降低(P<0.05),DM组AMPKα蛋白表达较DIO组显著降低(P<0.05);DIO组、DM组、INS组、MET组p-AMPKα蛋白表达较NC组显著降低(P<0.01)。结论大鼠肝组织visfatin表达可能与肝糖脂代谢有关联,visfatin可能未参与到二甲双胍激活AMPK降低血糖的机制中。

Objective To explore the effects of visfatin in glucose metabolism by testing the expression of visfatin in liver of rats in different glucose metabolic statuses.Methods SD rats were randomly divided into five groups：normal control group（NC group）,diet induce obesity group（DIO group）,diabetes mellitus group（DM group）,diabetes controlled by insulin group（INS group）and diabetes controlled by metformin group（MET group）.Tested the data of blood glucose（FPG）,triglyceride（TG）,total cholesterol（TC）,free fat acid（FFA）,fasting insulin（Fins）.The liver of rats was used to test visfatin,glucose-6-phosphatase（G-6-pase）mRNA by RT-PCR and visfatin,AMP-activated protein kinase-α（AMPKα）,phosphor-AMP-activated protein kinase-α（pAMPKα）protein by Western blot.Results FBG of group DM increased than group NC and DIO（P〈0.01）;FBG of group INS and MET decresed than group DM（P〈0.01）;HOMA-IR of group DIO and DM increased than group NC（P〈0.01）;HOMA-IR of group DM increased than group DIO（P〈0.01）.ISI of group DIO and DM decresed than group NC（P〈0.01）;ISI of group DM decreased than group DIO（P〈0.01）.TG of group DIO increased than group NC（P〈0.01）.TG of group INS and MET decreased than group DM（P〈0.05）.The level of TG and TC of group DM,INS and MET increased than group NC（P〈0.05）.The level of serum FFA of group DM,INS and MET were significantly higher than group NC（P〈0.05）;FFA of group DM increased than group DIO（P〈0.05）.The expression of visfatin mRNA of group DM increased than group NC and DIO（P〈0.05）;visfatin mRNA of group INS and MET decreased than group DM（P〈0.01）.Group DM,INS and MET had a significantly higher level of G-6-Pase mRNA of than group DIO（P〈0.05）;Group MET had a significantly lower level of G-6-Pase mRNA of than group DM（P〈0.05）.The expression of visfatin protein of group DM,INS and MET increased than group NC（P〈0.05）.The expression of AMPKαprotein of group DM,INS and MET decresed than group NC（P〈0.05）;AMPKαof group DM decresed than group DIO（P〈0.05）.The expression of p-AMPKαprotein of group DIO,DM,INS and MET decresed than group NC（P〈0.01）.Conclusion The expression of visfatin in liver of SD rats might have something to do with insulin resistance and diabetes.We could′t consider that visfatin can affect the pathway of metformin activated AMPK to decrease blood glucose.