In particular, melatonin facilitates insulin secretion of islet β-cells by directly sensitizing glucagon-like peptide-1 (GLP-1)/AMP/PKA/CREB signaling, attenuating apoptosis of β-cells, diminishing oxidative stress in cells exposed to hyperglycemia and maintaining the glucose-stimulated insulin response [74–77]. Here, GCG is linked to Hyperglycemia.