Vaccines and Immunology

Insulin and Insulin Therapy

Insulin is a peptide hormone produced by beta cells of the pancreatic islets determined in humans by the INS gene. It is considered to be the main anabolic hormone of the body. It regulates the metabolism of carbohydrates, fats and protein by promoting the absorption of glucose from the blood into liver, fat and skeletal muscle cells. In these tissues the absorbed glucose is converted into either glycogen via glycogenesis or fats (triglycerides) via lipogenesis, or in the case of the liver, into both. Glucose production and secretion by the liver is strongly inhibited by high concentrations of insulin in the blood. Circulating insulin also affects the synthesis of proteins in a wide variety of tissues. It is therefore an anabolic hormone, promoting the conversion of small molecules in the blood into large molecules inside the cells. When there is insulin resistance, the cells do not respond and do not expand, which causes the blood sugar to be too high.

The insulin that the body would typically produce is replaced by insulin therapy. Diabetes type 1 patients are required to consume insulin daily. When other medications and treatments for type 2 diabetes are unable to regulate blood sugar levels, insulin must be taken.