In Vitro Insulin Resistance Model: A Recent Update

Figure 3

The insulin signaling pathway in hepatocytes (HepG2 cell lines). Insulin binds to the insulin receptor (IR) and activates the downstream molecules, including IRS1/2, PI3-kinase (PI3K), and Akt. The activated Akt will inhibit GSK-3β and allow glycogen synthase (GS) to be in an active state to facilitate glycogen synthesis. It also suppresses the transcriptional activity of FOXO1, which will downregulate PEPCK and reduce hepatic glucose production. Insulin enhances de novo lipogenesis via sterol regulatory element binding protein 1c (SREBP-1c) to produce triacylglycerol (TAG).