The Effects Of Resistin On Activity And Gene Expression Of Glucokinase And Phosphoenolpyruvate Carboxykinase In Cultured Rat Liver Cells

Objective: To investigate the effect of resistin on enzymatical activityand gene expression of glucoskinase(GK) and phosphoenolpyruvatecarboxykinase(PEPCK) in cultured rat liver cells. It was also designed toexplore the role of resistin on heptic glucose metabolism and themechanism that how resistin affected liver Insulin Resistance(IR). Methods: Rat liver cells were incubated with resistin of different doses(10nM/L,50nM/L 100nM/L).Controlled liver cells were incubated withoutresistin.Glucose-6-phosphate dehydrogenase couple chromatometry andlactate dehydrogenase couple chromatometry were used to determineactivity of GK and PEPCK;RT-PCR was used to determine GK and PEPCKgene expression (corrected by β-actin). Results: Comparing with the control group,treatment with resistin of10nM/L and 50nM/L for 24h had no significant effect on activity of GK,butactivity of PEPCK increased significantly.At the dose of 100nM/L, activityof GK decreased significantly,and activity of PEPCK increased moresignificantly;RT-PCR result showed: Comparing with the controlgroup,treatment with resistin of 10nM/L and 50nM/L for 24h had nosignificant effect on gene expression of GK and PEPCK. At the dose of100nM/L,the glucokinase mRNA expression reduced significantly,but thePEPCK mRNA expression was promoted significantly. Conclusion: Lower doses(10nM/L and 50nM/L) of resistin has littleeffect on activity of GK,but increase activity of PEPCK significantly.Arelatively high dose(100nM/L) of resistin inhibite activity of GK andpromote activity of PEPCK more significantly.The resistin can inhabiteglycolysis, promote glyconeogenesis and increase blood glucose with sucheffect.The changes of activity of two enzymes are depended on the changesof doses of resistin. This effect is at least partly brought by the inhibition ofGK gene expression and the promotion of PEPCK gene expression.