Uromodulin (UMOD)
Uromodulin, also known as Tamm-Horsfall urinary glycoprotein (THP), is a protein primarily produced in the kidneys, specifically in the thick ascending limb of the loop of Henle. It is the most abundant protein found in normal urine, with healthy individuals excreting about 50 milligrams daily. While the precise functions of uromodulin remain unclear, it is believed to play a significant role in preventing urinary tract infections, particularly those caused by E. coli bacteria. Additionally, uromodulin may influence the formation of kidney stones and is thought to be connected to blood pressure regulation. The gene responsible for uromodulin production is located on the sixteenth chromosome, and mutations in this gene can lead to several hereditary kidney diseases. The protein was first identified in 1952 by biochemists Igor Tamm and Franc Horsfall Jr., who noted its effects on viruses and immune responses. Ongoing research aims to clarify the functional roles of uromodulin and its potential implications in kidney health and related conditions.
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Uromodulin
Uromodulin is a protein produced in the kidneys. It is also known as Tamm-Horsfall urinary glycoprotein (THP). More uromodulin in is in normal urine than any other protein. The role of uromodulin is not clearly understood, but it is thought to control bacteria that causes urinary tract infections. Uromodulin may play a role in the development of kidney stones and high blood pressure. It is also associated with several rare hereditary kidney diseases.
Uromodulin was identified in 1952 by Igor Tamm and Franc Horsfall Jr. Tamm was an Estonia-born biochemist, cytologist, and virologist while Horsfall was an American-born clinician and virologist. The men were working at the Rockefeller Institute for Medical Research when they discovered the protein bearing their name.
Virologists are physicians who focus on diagnosing, managing, preventing, and researching viruses. Tamm and Horsfall first noticed uromodulin because of the effect it had on viruses, specifically how it affected the viruses responsible for influenza and mumps.
In 1985, researcher A.V. Muchmore and J.M. Decker identified a protein that affected the production of T-cells. T-cells are part of the immune system that attacks foreign substances in the body. Muchmore and Decker named this protein uromodulin because it was found in urine, and they thought it modulated or regulated the immune system’s response to infections. A few years later, other researchers determined that uromodulin and Tamm-Horsfall urinary glycoprotein are the same. Glycoproteins are proteins with carbohydrate chains attached to side chains of amino acids.
Overview
Uromodulin is made by the cells of the thick ascending limb of the loop of Henle, which is a U-shaped structure connecting the millions of nephrons that filter fluids in the kidneys. Embryos begin producing uromodulin between eight to sixteen weeks after conception. It is present in the amniotic fluid that surrounds and protects the growing embryo. Healthy people make about 50 milligrams of uromodulin per day.
Researchers are still working to understand what uromodulin does. It is believed to help prevent infections in the urinary tract, particularly those caused by E. coli bacteria. This common type of water-and food-borne bacteria causes severe kidney damage in some cases. Uromodulin may also play a role in the formation of kidney stones, which are made up of calcium deposits. Uromodulin may play a role in limiting the collections of calcium that turn into stones.
The gene that regulates a person’s production of uromodulin is located on the sixteenth chromosome or what is known as the UMOD gene. Defects in this gene can result in the development of several hereditary conditions known as uromodulin-related diseases. They include familial juvenile hyperuricemic nephropathy and medullary cystic disease (II-type).
Some researchers think that variations in the UMOD gene may also have to do with the development of high blood pressure. The kidneys play a role in blood pressure by regulating the balance of water, salts, and other minerals. Since the production of uromodulin is controlled by the UMOD gene, researchers are investigating whether they can test levels of uromodulin to identify kidney problems that lead to high blood pressure and other health problems.
Bibliography
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