Fig. 1

Metabolic signaling of insulin is anabolic. Insulin signaling through the insulin receptor engages several pathways and results in an anabolic state of metabolism. The canonical pathway via phosphokinases PI3K and AKT/PKB promotes glucose uptake and glycogen and lipid syntheses, whereas lipolysis is inhibited in adipocytes, as well as hepatic gluconeogenesis. In addition, AKT kinases activate mTORC1 which supports de novo lipogenesis and protein synthesis. The insulin signaling pathway via SHC and the MAP kinases MEK and ERK promotes cell proliferation and protein synthesis. Another insulin signaling pathway involves NOX4 and the inhibition of PTEN, an inhibitor of the PI3K-AKT pathway