RESUMEN
Objective To investigate the effect of Cyclocarya paliurus(Batal.)lljinskaja polysaccharides on insulin resistance in type 2 diabetic rats by regulating glucose transporter 4(GLUT4)translocation in islet and liver.Methods High-fat diet combined with low-dose streptozotocin(35 mg·kg-1)to induce type 2 diabetes model,all the rats were randomly divided into model control group,Cyclocarya paliurus polysaccharides groups(5,10 g·kg-1)and metformin group(0.25 g·kg-1),and treated for eight weeks(n=9 in each group).Fasting glucose and lipid were determined.Histopathology of rat islet and liver were observed by hematoxylin and eosin staining.Protein expressions of phosphorylated phosphoinositide-3-kinase(p-PI3K),phosphorylated serine-threonine kinase 1(p-Akt1),and GLUT4 in islet were measured by immunohistochemistry staining.GLUT4 translocation in the islet and liver was detected by immunofluorescence.Results Compared with the model control group,the Cyclocarya paliurus polysaccharides group and metformin group had declined fasting glucose levels and increased high-density lipoprotein(P＜0.05).The structure of the islets and liver was relatively complete.The content of p-PI3K,p-Akt1 and GLUT4 in the islet increased(P＜0.05).GLUT4 translocation in the liver and islet enhanced(P＜0.05).Conclusions Cyclocarya paliurus polysaccharides alleviate glucose and lipid metabolism disorders.The mechanism may lay in it activating protein expressions of p-PI3K,p-Akt1,and GLUT4 in islet cells.GLUT4 translocation to the islet and liver cell membrane are increased to regulate peripheral islet resistance.
