INS and diabetes mellitus: Cinnamic acid and some of its derivatives have the potential to be applied in the treatment of diabetes because of their many useful properties including (1) increased glucose uptake, adiponectin secretion, insulin secretion and hepatic glycolysis; (2) improved functionality of pancreatic β cells; (3) reduced adipogenesis; (4) improved hepatic gluconeogenesis, protein glycation, insulin fibrillation and intestinal glucose absorption and (5) decreased activity of certain enzymes, including α-glucosidase, dipeptidyl peptidase-4, pancreatic α-amylase and protein tyrosine phosphatase 1B [213].