The prevalence of type 2 diabetes in united States is at a higher rate. According to the statistics provided by American Diabetes Association, in 2012, 29.1 million Americans had diabetes. If the records are evaluated on percentage basis, 9.3% of the population suffered from diabetes. In 2010, the percentage was comparatively less, about 8.3%. Of the total patients (29.1 million), the number of cases that were undiagnosed was 8 million. The percentage of undiagnosed cases, in 2010, was comparatively less. Those who were aged above 65 years of age had a higher prevalence of diabetes, counting to approximately 25.9%, inclusive of the diagnosed as well as undiagnosed cases. Type 2 diabetes is still the 7th leading cause of death in USA. In 2010, the number of deaths recorded were around 69,071 and the major underlying cause of death was diabetes. Amongst the youth of united States, the majority of them suffer from or have been diagnosed with type 1 diabetes. In 2008-09 reports, the annual incidence was found to be around 18436 youths who suffered from type 1 diabetes and 5089 youths who suffered from type 2 diabetes. The statistical records have also highlighted the most common complications associated with type 2 diabetes. Majority of the people face complications of hypoglycemia, hypertension, CVD death, heart attacks, blindness and other eye related problems (American Diabetes Association, 2014).
Insulin is a anabolic peptide hormone that is made up of 51 amino acid residues. It is secreted by ? cells in the Islets of Langerhans as its precursor. The molecule of insulin is made up of two chains A and B that are interconnected by disulfide bonds. The main function of insulin is to stimulate the uptake of glucose from the systemic circulation and simultaneously initiates the suppression of hepatic gluconeogenesis. This makes insulin responsible for maintaining the glucose homeostasis and helps in preventing the metabolic disorder of diabetes mellitus. Diabetes is a disorder that is characterized by decrease in the tolerance of glucose that is caused due to reduced sensitivity of insulin. The molecular weight of insulin chain is about 5802 and its iso electric point is pH5.5. The first chain or the A chain consists of 21 amino acid residues while the second chain or the B chain is made up of 30 residues. The N terminal of A chain is connected to an anti parallel C terminal helix while the B chain has a helical segment that is central. The two chain are connected via 2 disulfide bonds. The bond is such that the N and C terminal helices of chain A are connected to the central helix of chain B. In pro insulin, the bond is formed between the N terminal of A chain and C terminal of B chain. Insulin is generally coded on the short arm of chromosome 11. Zinc containing hexamers are formed by insulin and these hexamers are insoluble and precipitate as crystals. The total secretion of ? cells is around 6% (proinsulin and zinc). The secretion of insulin results into the portal veins and this secretion is reflecting, pursatile and a summation of the secretory bursts that happens from a million of the islet cells.
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American Diabetes Association. (2014). Statistics about diabetes. Retrieved on 8th February, 2014 from