Immunochemical detection of imidazolone in uremia and rheumatoid arthritis

The advanced glycation end-product imidazolone is formed by reaction of arg inine with 3-deoxyglucosone (3-DG), a reactive intermediate of the Maillard reaction, whose formation is non-oxidative. Using an antibody specific to this 3-DG-derived AGE, we demonstrated the presence of imidazolone-modified proteins in vivo in the urine and dialysate of patients with chronic renal failure, in the synovial fluid of patients with rheumatoid arthritis, as w ell as in vitro in human serum and human serum albumin incubated with gluco se. Furthermore, we could show that in uremic patients the dimeric form of beta(2)-microglobulin is more susceptible to imidazolone modification than the monomeric one. Thus, the immunochemical detection of imidazolone may be a good marker for 3-DG-derived AGE modification in vivo and in vitro permi tting a differentiation between the oxidative and the non-oxidative pathway of AGE generation. (C) 2000 Elsevier Science B.V. All rights reserved.