Effects of nonenzymatic glycation and fatty acids on functional properties of human albumin

Human serum albumin nonenzymatically condenses with glucose to form stable Amadori adducts that are increased with the hyperglycemia of diabetes. The present study evaluated the influence of fatty acids, which are major endogenous ligands, on albumin glycation and of glycation on albumin conformation and exogenous ligand binding. Physiologic concentrations of palmitate, oleate, and linoleate reduced the ability of albumin to form glucose adducts, whereas glycation decreased intrinsic fluorescence, lowered the affinity for dansylsarcosine, and diminished the fatty acid-induced increase in limiting fluorescence of protein-bound warfarin that was observed with nonglycated albumin. The findings indicate that fatty acids impede the ability of albumin to undergo Amadori glucose modification and induce conformational changes affecting exogenous ligand binding, and that nonenzymatic glycation of albumin induces alterations in structural and functional properties that may have import in lipid transport and atherogenesis.