Fig. 6

Role of adiponectin signaling in pancreatic β-cell. Adiponectin-induced activation of its receptors, AdipoR1 or AdipoR2, increases insulin secretion by increasing the transcription of insulin gene (INS) through the upregulation of transcription factors pancreatic and duodenal homeobox (Pdx)1 and MafA as well as increasing exocytosis of insulin granules. Adiponectin decreases the rate of hyperglycemia and lipogenesis through the activation of AMPK. Adiponectin-induced activation of AMPK also increases fatty acid oxidation through the inhibition of acetyl-CoA carboxylase (ACC). Adiponectin-induced activation of both MEK-ERK1/2 and PI3-AKT signaling pathways increase β-cell viability and decrease β-cell apoptosis through the inhibition of IL-1β, IFN-γ, palmitate and hyperglycemia