[Mechanism of rosiglitasone to improve glucose-uptake of 3T3-L1 adipocyte with insulin resistance induced by dexamethasone and insulin].

OBJECTIVE:To study the mechanism of rosiglitasone to improve glucose-uptake of 3T3-L1 adipocyte with insulin resistance induced by dexamethasone and insulin. METHODS:Insulin resistance was induced to 3T3-L1 adipocyte after chronic treatment of dexamethasone and insulin. The insulin resisted 3T3-L1 adipocyte was treated with 10(-5) mol/L of rosiglitasone for 48 h. The mRNA, protein of glucose transporter GLUT4 and CAP gene were then examined. RESULTS:(1) Rosiglitasone increased the expression of GLUT4 mRNA and protein inhibited by dexamethasone and insulin although it had not reached a normal level. (2) Rosiglitasone increased the mRNA of CAP, which remained unchanged during insulin resistance. CONCLUSION:Rosiglitasone, an insulin sensitizer, might up-regulate GLUT4 and CAP along with the peroxisome proliferators activated receptor gamma (PPAR-gamma), which not only increases the GLUT4, but also activates the CAP-depended signaling pathway; improves the translocating of GLUT4 to the cell membrane; and increases the ability of glucose-uptake of cells.