Oxidative Stress in Diabetes Mellitus: Is There a Role for Hypoglycemic Drugs and/or Antioxidants?

The most recent statistics indicate that the global prevalence of diabetes mellitus, estimated as 366 million in 2011, will increase to 522 million by 2030 (Whiting et al., 2011). Diabetes mellitus is a metabolic disorder of multiple etiology characterized by chronic hyperglycemia with disturbances of carbohydrate, fat and protein metabolism resulting from defects in insulin secretion and/or insulin action (ADA, 2011). There are basically two types of diabetes mellitus: type 1 and type 2 diabetes mellitus. Type 1 diabetes mellitus, an autoimmune disease, is characterized by the loss of pancreatic ┚-cells resulting in absolute insulin deficiency. It accounts for about 5-10 % of all newly diagnosed diabetes mellitus (ADA, 2011). On the other hand, type 2 diabetes mellitus is characterized by insulin resistance and ┚ cell dysfunction. It remains the most common form of diabetes mellitus and constitutes about 90-95 % of all diabetes cases (ADA, 2011). In spite of the availability of different classes of oral hypoglycemic drugs, the incidence of microvascular complications (nephropathy, retinopathy and neuropathy) and macrovascular complications atherosclerosis, coronary artery disease, peripheral arterial disease and stroke continues to rise unabated in diabetic patients, even with treatment (Roglic and Unwin, 2010).