title: Glycation of aspartate aminotransferase by methylglyoxal, effect of hydroxycitric and uric acid.
abstract: Glycation is a process closely related to the aging and pathogenesis of diabetic complications. Reactive alpha-dicarbonyl compounds (e.g., methylglyoxal) are formed during middle stage of glycation reaction. Compounds that would inhibit the glycation process have been seeked for years. The objective of this study was to investigate the inhibitory effect of hydroxycitric (0.25-2.5 mM) and uric acid (0.4-1.2 mM) on middle stage of protein glycation in vitro using the model containing aspartate aminotransferase (AST) and 0.5 mM methylglyoxal. Hydroxycitric acid, at all tested concentrations, reduced AST activity decrease and formation of fluorescent AGEs during incubation of the enzyme with methylglyoxal at 37 degrees C. This compound also prevented formation of high-molecular weight protein cross-links and changes in molecular charge of AST caused by glycation. Uric acid showed no positive anti-glycation activity. The results support the hypothesis that hydroxycitric acid has beneficial effects in controlling protein glycation.
authors.affiliation: Department of Biochemical Sciences, Charles University in Prague, Faculty of Pharmacy in Hradec Kralove, Heyrovského 1203, 50005, Hradec Kralove, Czech Republic. Iva.Bousova@faf.cuni.cz
authors.forename: Iva
authors.initials: I
authors.lastname: Bousová
authors.forename: Eliska
authors.initials: E
authors.lastname: Bacílková
authors.forename: Sanja
authors.initials: S
authors.lastname: Dobrijević
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Drsata
mesh_terms: D000818:Animals; D001219:Aspartate Aminotransferases / Q000737:chemistry / Q000378:metabolism*; D015153:Blotting, Western; D002951:Citrates / Q000494:pharmacology*; D003432:Cross-Linking Reagents / Q000494:pharmacology; D005453:Fluorescence; D017127:Glycation End Products, Advanced / Q000378:metabolism; D006031:Glycosylation / Q000187:drug effects; D009952:Ornithine / Q000031:analogs & derivatives / Q000378:metabolism; D020836:Protein Structure, Quaternary; D011743:Pyrimidines / Q000378:metabolism; D011765:Pyruvaldehyde / Q000494:pharmacology*; D034421:Sus scrofa; D014527:Uric Acid / Q000494:pharmacology*
chemical_list: D002951:Citrates; D003432:Cross-Linking Reagents; D017127:Glycation End Products, Advanced; D011743:Pyrimidines; C107313:argpyrimidine; D014527:Uric Acid; D011765:Pyruvaldehyde; C007999:hydroxycitric acid; D009952:Ornithine; D001219:Aspartate Aminotransferases