Unlike type 2 diabetes, which is caused by the loss of insulin sensitivity, type 1 diabetes is caused by insulin deficiency following destruction of insulin-producing pancreatic β cells. Recent epidemiologic studies revealed that the incidence for type 1 diabetes in most regions of the world has increased by 2-5% (2).
Although most commonly presented in childhood, type 1 diabetes also accounts for 5-10% cases of adult diabetes (1). Despite the increasing rate of Type 2 diabetes in the United States, type 1 diabetes accounts for over 2/3 of new adolescent diabetes diagnoses. Type 1 diabetes mellitus, used to known as juvenile diabetes, is typically developed in children and juveniles. Diabetes can be categorized into two main types: type 1 and type 2. Unfortunately, the therapy of diabetes remains unsatisfied despite of extensive studies in the last decades. In United States alone, according to the statistical fact sheet released 2011 by American Diabetes Association, 25.8 million children and adults accounting for 8.3% of the population are affected by diabetes. As one of the major health problems in the world, diabetes affects over 346 million people worldwide.