INS and type 2 diabetes mellitus: However, the use of insulin remains essential at the evolutionary stage of the disease, because insulin resistance which is a characteristic of type 2 diabetes, leads over time to the depletion of beta cells of islets of Langerhans.2 In the United Kingdom Prospective Diabetes Study (UKPDS) study,3 less than 25% of normal insulin secretion was observed 6 years after diagnosis of the disease.