(A–D) Inhibitory effect of PI3K inhibitor on PI3K-Akt signaling pathway in INS-1 and HepG2 cells. (A) Effect of PI3K inhibitor on p-PI3K and p-Akt levels in INS-1 cells. (C) Effect of PI3K inhibitor on p-PI3K, p-Akt, and GLUT4 levels in HepG2 cells. Cells were treated with or without 20 μM PI3K inhibitor LY294002 for 24 h. (B, D) Quantification of bands relative to GAPDH intensities using Image J software. Values are expressed as means ± SD from three independent experiments. ***P < 0.01. #P < 0.05, ##P < 0.01, ###P < 0.001 as compared to the model.