Insulinë

Insulinë is a term occasionally used to refer to insulin, the peptide hormone produced by pancreatic beta cells in the islets of Langerhans. Insulin regulates blood glucose by promoting cellular glucose uptake and inhibiting hepatic glucose production, while also influencing fat and protein metabolism.

Its secretion rises after meals in response to increased blood glucose and nutrient signals. Insulin acts mainly through binding to the insulin receptor, triggering signaling pathways that move GLUT4 transporters to the cell surface, enabling glucose entry into muscle and adipose tissues.

Clinically, insulin therapy is essential for many people with diabetes. It is used in most cases of type 1 diabetes and in some individuals with type 2 diabetes to achieve glycemic control. Preparations vary in duration and onset: rapid-acting analogs, short-acting regular insulin, intermediate-acting, and long- or ultra-long-acting analogs. Administration is usually subcutaneous, though inhaled insulin products have been approved in some regions. All insulin products are produced by recombinant DNA technology.

Pharmacologic history: insulin was first isolated in 1921 and rapidly purified for medical use. Mechanistically, insulin signaling promotes glucose uptake, glycogen synthesis, and lipid storage, while suppressing glucose production. It also influences protein synthesis and overall energy balance.

Safety and storage considerations include the risk of hypoglycemia and possible weight gain. Unopened vials are typically refrigerated; many products tolerate room temperature after opening for a limited time. Repeated injections at the same site can cause lipodystrophy, underscoring the need for rotation of injection sites.