Objective: To investigate the effect of glucagon-like peptide-1 (GLP-1) on glycolipid metabolism in 3T3-L1 adipocytes and explore the mechanism.
Methods: 3T3-L1 adipocytes were treated with GLP-1, insulin, or both for 24 h, and Western blotting was used to analyze the expression levels of adipose triglyceride lipase (ATGL), glucose transporter type 4 (GLUT4), Akt1, Akt2 and phosphorylated Akt in the cells. Immunofluorescence was used to observe lipid content in 3T3-L1 adipocytes.
Results: Akt1 and Akt2 were not activated by insulin stimulation in 3T3-L1 adipocytes. Akt was phosphorylated by GLP-1 stimulation, which inhibited the expression of ATGL and increased the translocation of GLUT4 from the intracellular membranes to plasma membranes. These changes were more obvious under the synergistic effect of insulin in 3T3-L1 adipocytes.
Conclusion: GLP-1 decreases lipolysis by inhibiting the expression of ATGL and improves insulin resistance by increasing the translocation of GLUT4 in 3T3-L1 adipocytes.