Transcortin belongs to the group of globulins. They serve to transport various components such as hormones fromm the site of production to the site of action. Transcortin carries glucocorticoids and progesterone through the blood.
What is transcortin?
Transcortin is a globulin. These are also called storage or transport proteins of blood plasma. Globulins are divided into four subgroups. This classification is based on protein size. These are determined by a special laboratory test in which the blood plasma is analyzed. This method is called serum protein electrophoresis. The group of α1-globulins includes thyroxine-binding globulin, prothrombin, which plays an essential role in blood clotting, and transcobalamin, which binds vitamin B12. Transcortin itself also belongs to the group of α1-globulins. The Gc-globulins, they are vitamin D binding globulins, α1-antityropsin and bilirubin transporters are also α1-globulins. The α2-globulins include hemoglobin-binding globulin, α2-macroglobulin, caeruloplasmin, plasminogen, α2-antithrombin, and α2-haptoglobin. The third group is the β-globulins. Their main function is to transport β-lipoproteins and lipids, essential components of the plasma membrane of cells in the body. The β-globulins include fibrinogen, hemopexin, and transferrin, which is important for iron transport in the blood. In the fourth group are the γ-globulins, which are also known as immunoglobulins. They are antibodies that are part of the body’s immune defenses.
Function, action, and tasks
Transcortin binds and transports glucocortocoids and progesterone. Glucocorticoids are steroid hormones that are produced in the adrenal glands. Glucocorticoids include cortisol and corticosterone. They are synthesized from cholesterol. This is absorbed mainly through food. It is then broken down again in the liver after it is no longer needed. They play an essential role in energy metabolism in humans. They promote gluconeogenesis, the formation of carbohydrates with proteins as starting material. This results in the release of amino acids, fatty acids and glucose. Glucocorticoid-containing drugs are used for the treatment of bronchial asthma and generally for the treatment of inflammation. Progesterone is also a steroid hormone and belongs to the group of progestins, which are also called corpus luteum hormones. In women, it is produced by the corpus luteum, also known as the copus luteum, during a specific phase of the menstrual cycle by the granule cells. It is increased during pregnancy and is then produced by the placenta. It is also produced in smaller quantities by the adrenal cortex. Men produce progesterone in the testes by intermediate Leydig cells. They stimulate the production of sperm in the testes. Progesterone is also produced from cholesterol. Progesterone plays an important role in the formation of the endometrium. It also prevents re-fertilization of an egg while a follicle is maturing.
Formation, occurrence, properties, and optimal values
The site of formation of transcortin is the liver. The synthesis of transcortin is controlled by the hormone estrogen. It is a 52-kDa protein that occurs at a concentration of about 37 mg/L in the blood. The amount of transcortin can give an indication of the state of health of a person. On the one hand, a decrease in this amount may indicate liver cirrhosis or hepatitis. On the other hand, an increase may indicate pregnancy. Taking birth control pills also results in an increased amount of transcortin. An increased amount of transcortin can lead to an increased amount of cortisol in the blood. However, this is not necessarily the case; it is also possible that there is an increased amount of transcortin, but the amount of free cortisol is decreased. Therefore, cortisol and transcortin must be determined independently.
Diseases and disorders
When the amount of transcortin is decreased, one possible cause is liver cirrhosis. This is a serious disease of the liver that severely limits its ability to function. This liver disease is chronic and cirrhosis is called the final stage of this disease. There is no cure for cirrhosis of the liver.It often results from the excessive consumption of alcohol, which causes damage to the liver. However, there are many other causes of liver cirrhosis, such as hepatitis. In cirrhosis of the liver, necrosis, or death, of cells in the liver occurs. The body’s immune response involves macrophages, monocytes and granulocytes. The spleen also enlarges, which is a sign of this immune reaction. The liver decreases the production of various globulins such as transcortin. In addition, it loses its function of detoxifying the body from various substances. If there is an increase in the level of transcortin, it is possible, but not necessarily the case, that the amount of cortisol is also increased. This condition is called Cushing’s syndrome and can occur as a consequence of osteoporosis, diabetes mellitus, chronic hypertension or obesity. This disease leads to the development of the typical full moon face, menstrual disorders in women, acne, an increased incidence of kidney stones, and muscle weakness. The cause of Cushing’s syndrome is increased production of cortisol by the adrenal cortex due to increased production of adrenocorticotropic hormone in the anterior pituitary gland. This hormone regulates the production and secretion of cortisol by the adrenal cortex.
