Assay of advanced glycation endproducts (AGEs): surveying AGEs by chromatographic assay with derivatization by 6-aminoquinolyl-N-hydroxysuccinimidyl-carbamate and application to Nepsilon-carboxymethyl-lysine- and Nepsilon-(1-carboxyethyl)lysine-modified albumin.

摘要: Glycation of proteins leads to the formation early glycation adducts (fructosamine derivatives) and advanced endproducts (AGEs). Formation AGEs has been linked development cataract, diabetic complications, uraemia, Alzheimer's disease other disorders. are a group compounds diverse molecular structure biological function. To characterize AGE-modified used in studies structural functional effects glycation, an assay was developed that surveys content proteins. The procedure involved enzymic hydrolysis protein substrate, derivatization hydrolysate with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) HPLC resulting fluorimetric detection. Structural isomers methylglyoxal-derived hydroimidazolone, glyoxal-derived 3-deoxyglucosone-derived hydroimidazolone N(delta)-(4-carboxy-4,6-dimethyl-5,6-dihydroxy-1,4,5,6-tetrahydropyrimidin-2-yl)-ornithine (THP) were determined for first time. intrinsic fluorescence (argpyrimidine, pentosidine) assayed without derivatization. Limits detection 2-17 pmol levels recovery 50-99%, depending on analyte. AQC resolved epimeric hydroimidazolones THP. Hydroimidazolones, THP argpyrimidine short-to-intermediate stability under physiological conditions, half-lives 1-2 weeks. Their measurement provides further insight into process. applied characterization human serum albumin minimally highly modified by N(epsilon)-carboxymethyl-lysine N(epsilon)-(1-carboxyethyl)-lysine.