A research group led by Miyazaki University and Kurume University (in addition to Saitama University, Agricultural Research Organization, Osaka University, Kurume National College of Technology) is the final stage of the blood decomposition process, and the in vivo reaction that causes neonatal jaundice The mechanism was clarified by making full use of the three-dimensional structure analysis method of proteins.It is said that it will give a great clue to the development of a therapeutic drug for jaundice for which there is no effective drug so far.The research results were published in the British scientific journal "Nature Communications".
Heme, which is known as the main component that carries oxygen in the blood, is sequentially converted from biliverdin to a pigment called bilirubin in the process of its decomposition and excreted from the body.Bilirubin is a yellow pigment and is also the causative agent of neonatal jaundice.It was known that a protein called biliverdin reductase converts biliverdin to biliverdin, but the specific mechanism has been a mystery for more than 50 years.
This time, the reaction mechanism of biliverdin reductase was elucidated at the molecular and atomic levels by a method called X-ray crystal structure analysis.It was found that biliverdin reductase takes up two biliverdins at the same time, one of which converts the other to produce bilirubin.The in vivo reaction of such a mechanism is unprecedented, and we succeeded in demonstrating it as the first discovery in the world.
Currently, mild jaundice is treated with light irradiation, but for severe neonatal jaundice, there is no effective therapeutic agent, so it is necessary to completely replace the blood.If a drug that inhibits the reaction of biliverdin reductase can be developed, it will be possible to control the amount of bilirubin synthesis, which may be an epoch-making therapeutic drug for jaundice.This achievement is expected to lead to the development of a therapeutic drug for severe neonatal jaundice (bilirubin encephalopathy) caused by overproduction of bilirubin.
