(2S, 1'R)/(2S, 1'S)-2-Amino-6-(1'-carboxy-ethylamino)-he xanoic acid

N^ε-(1-Carboxyethyl)-L-lysine (CEL) is an advanced glycation end product (AGE) produced by the reaction of methyl glyoxal with lysine residues in proteins. Protein bound, but not free, CEL binds to the receptor for AGEs (RAGE). CEL levels are elevated in the lens of diabetic patients with cataract. Long-term caloric restriction decreases CEL levels in rat heart mitochondria. It decreases glutamate uptake and secretion of S100B in rat hippocampal slices in a RAGE-independent manner when used at a concentration of 1 mM.

CEL and CML are two stable, nonenzymatic chemical modifications of protein lysine residues resulting from glycation and oxidation reactions.

ChEBI: N(6)-(1-carboxyethyl)-L-lysine is a L-lysine derivative formed during the reaction between methylglyoxal and protein. CEL is a homologue of N(epsilon)-(carboxymethyl)lysine (CML), an advanced glycation end-product that is formed on reaction of glyoxal or glycolaldehyde with protein and on oxidative cleavage of fructoselysine, the Amadori adduct formed on glycation of protein by glucose. It is a L-lysine derivative and a non-proteinogenic L-alpha-amino acid.

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