Insulin, a protein hormone produced near the pancreas and it regulates blood sugar (glucose) in blood. Insulin is hardened as a replacement for treatment of diabetes. The hormone is synthesized in the beta cells, which into in hormone-secreting cells of the pancreas and is called islets of Langerhans. The hormone is synthesized in the beta cells, which enter in hormone-secreting cells of the pancreas and is called islets of Langerhans. The solemn word of honour “insulin” is from the Latin insula – islet, it indicates on the island provenience of the hormone.