Metabolic changes in diabetes.

Diabetes is not a single disease but a group of diseases characterised by hyperglycaemia. The most important regulator of glucose uptake from the blood is the hormone insulin, which is produced by islet beta cells and acts on insulin receptors to promote nutrient uptake and processing. A decrease in either insulin secretion or sensitivity can cause diabetes. Exposure to prolonged hyperglycaemia causes reversible and then irreversible changes to tissue metabolism and structure. These changes may be responsible for the potentially devastating complications of diabetes.