Methylglyoxal (MG)

Methyl glyoxal (MG) is a highly reactive alpha-oxoaldehyde that plays an important role in non-enzymatic glycosylation reactions, formation of Advanced Glycation End products (AGEs) and other complications associated with hyperglycemia and related disorders. Unlike sugars, glycation by MG is predominantly arginine directed, which is particularly more damaging since arginine residues have a high-frequency occurrence in ligand and substrate recognition sites in receptor and enzyme active sites.

In organisms, methylglyoxal is formed as a side-product of several metabolic pathways. It may form from 3-amino acetone, which is an intermediate of threonine catabolism, as well as through lipid peroxidation. However, the most important source is glycolysis. Here, methylglyoxal arises from non enzymatic phosphate elimination from glyceraldehyde phosphate en dihydroxyacetone phosphate, two intermediates of glycolysis.