内脏脂肪素对糖尿病小鼠肝组织AKT、FoxO1及PEPCK表达的影响

Effects of visfatin on AKT,FoxO1 and PEPCK expressions in KKAy mice liver tissue

目的观察内脏脂肪素(visfatin)对糖尿病小鼠肝脏蛋白激酶B(AKT)、叉头转录因子1(FoxO1)及磷酸烯醇式丙酮酸羧基酶(PEPCK)表达的影响,探讨visfatin在肝组织糖异生过程中的作用。方法 16只C57BL/6J小鼠随机分为正常对照组及饮食诱导高脂组,24只KKAy小鼠随机分为糖尿病模型组、visfatin组及visfatin+LY294002组,分别予PBS、PBS、PBS、visfatin(6μg/kg,0.05m L/10g)、visfatin(6μg/kg,0.05 m L/10g)+LY294002(0.35μg/g,0.05 m L/10g)干预3 d后,测定血糖、血脂及胰岛素,计算HOMA-IR,RT-PCR测定肝组织AKT、FoxO1、PEPCK的mRNA表达,免疫组化测定肝脏组织AKT、FoxO1蛋白表达。结果糖尿病模型组AKT mRNA及蛋白表达较正常对照组及高脂组均显著降低(P<0.01),FoxO1mRNA及其蛋白、PEPCK mRNA表达较正常对照组均显著增高(P<0.01);visfatin组AKT mRNA及蛋白表达较糖尿病模型组显著增高(P<0.05),FoxO1 mRNA及其蛋白、PEPCK mRNA表达较糖尿病模型组均显著降低(P<0.01);visfatin+LY294002组AKT mRNA及蛋白表达较visfatin组显著降低(P<0.01),FoxO1蛋白表达较visfatin组显著增高(P<0.05)。结论 Visfatin可能通过PI3K/AKT途径调节FoxO1的表达,参与到肝组织糖异生过程中。

Objective To observe the effects of visfatin on AKT,FoxO1 and PEPCK expressions in KKAy mice liver tissue,and further explore the role of visfatin in gluconeogenesis of liver tissue. Methods Sixteen C57 BL/6 J mice were randomly assigned to two groups： normal control group（ n = 8） and high lipid group（ n = 8）. Twenty-four KKAy mice were randomly assigned to three groups： Diabetic model group（ n = 8）,visfatin group（ n =8）,LY294002 and visfatin group（ n = 8）. All groups were taken blood sample to detecte FPG,TG,TC,LDLC,HDLC,FINS,HOMA-IR and ISI. Mouse liver tissues were collected to measure the mRNA and protein expressions of AKT,calculate the FoxO1 and PEPCK with PCR and immunohistochemical analysis,respectively. Results The expression of AKT mRNA and protein in liver tissue of Diabetes model group were significantly lower than that in normal control group and high lipid group（ P〈0. 01）. AKT mRNA and protein expressions in visfatin group were higher than those in Diabetes model group（ P〈0. 05）. AKT mRNA and protein expressions in LY294002 and visfatin group were significantly lower than those in visfatin group（ P〈0. 01）. The expression of FoxO1 mRNA and protein in liver tissue of Diabetes model group was significantly higher than that in normal control group（ P〈0. 01）. FoxO1 mRNA and protein expressions in visfatin group were lower than those in Diabetes model group（ P〈0. 01）. FoxO1 protein expression in visfatin and LY294002 group was higher than that in visfatin group（ P〈0. 05）. The expression of PEPCK mRNA and protein in liver tissue of Diabetes model group was significantly higher than that in normal control group（ P〈0. 01）. PEPCK mRNA and protein expressions in visfatin group were lower than those in Diabetes model group（ P〈0. 01）. Conclusion Visfatin regulates the expression of FoxO1 through PI3 K/AKT signal pathway,which plays an important role in gluconeogenesis.