INS and type 2 diabetes mellitus: Generally, current therapeutic strategies for type 2 diabetes mainly involve insulin and four main classes of oral antidiabetic agents that stimulate pancreatic insulin secretion (sulphonylureas and rapid-acting secretagogues), reduce hepatic glucose production (biguanides), delay digestion and absorption of intestinal carbohydrate (a-glucosidase inhibitors) or improve insulin action (TZDs)[15].