Elevated serum levels of 3-deoxyglucosone, a potent protein-cross-linking intermediate of the Maillard reaction, in uremic patients.

3-Deoxyglucosone (3-DG) has been identified as an intermediate of the Maillard reaction in vitro. We measured serum 3-DG levels using gas chromatography/mass spectrometry and found a marked elevation in serum 3-DG levels in uremic patients compared with healthy subjects. The uremic patients with diabetes showed significantly higher serum concentrations of 3-DG than those without diabetes. 3-DG was demonstrated to be a potent protein-cross-linking agent in the reaction with lysozyme, leading to browning, fluorescence formation and polymerization of the protein by formation of advanced glycation end products (AGE). The increase in serum 3-DG levels in the uremic patients suggests that 3-DG may be responsible for the development of uremic complications by promoting the formation of AGE.