Researchers discover fundamental roles of glucosamine in bra
Now open: Certificate Course in Management of Covid-19 by Govt. Of Gujarat and PlexusMDKnow more...Now open: Certificate Course in Management of Covid-19 by Govt. Of Gujarat and PlexusMDKnow more...
Using novel imaging methods for studying brain metabolism, researchers have identified the reservoir for a necessary sugar in the brain. Glycogen serves as a storage depot for the sugar glucose. Researchers discovered that glucose was not the only sugar contained in glycogen in the brain. Brain glycogen also contained another sugar called glucosamine.

Glycosylation defects are a hallmark of many nervous system diseases. However, the molecular and metabolic basis for this pathology is not fully understood.

In this study, researchers found that N-linked protein glycosylation in the brain is metabolically channeled to glucosamine metabolism through glycogenolysis. They discovered that glucosamine is an abundant constituent of brain glycogen, which functions as a glucosamine reservoir for multiple glycoconjugates. They demonstrated the enzymatic incorporation of glucosamine into glycogen by glycogen synthase, and the release by glycogen phosphorylase by biochemical and structural methodologies, in primary astrocytes, and in vivo by isotopic tracing and mass spectrometry.

Using two mouse models of glycogen storage diseases, investigators showed that disruption of brain glycogen metabolism causes global decreases in free pools of UDP-N-acetylglucosamine and N-linked protein glycosylation.

These findings revealed fundamental biological roles of brain glycogen in protein glycosylation with direct relevance to multiple human diseases of the central nervous system.

Cell Metabolism
Source: https://doi.org/10.1016/j.cmet.2021.05.003
Like
Comment
Share