Urinary pyrraline as a biochemical marker of non-oxidative Maillard reactions in vivo.
The presence of pyrraline, a non-oxidative glucose-derived Maillard reaction product in plasma proteins has been established previously. In this study we have investigated the presence of pyrraline in human urine to determine whether pyrraline-containing proteins are metabolized or selectively retained. Pyrraline was detected by means of HPLC, and its presence was confirmed by UV and electrospray-mass spectrometry. The quantification of pyrraline in urine from healthy individuals showed 1.21 +/- 0.4 micrograms/mg creatinine. In urine from diabetic patients, pyrraline levels varied considerably, although the mean level was higher than in healthy subjects (1.37 +/- 0.6 micrograms/mg creatinine). These data further support the presence of a catabolic pathway for advanced non-oxidative Maillard reaction products in vivo and suggest their role in the pathogenesis of diabetes.
Portero-Otín
M
M
Department of Basic Medical Sciences, University of Lleida, Spain.
Pamplona
R
R
Bellmunt
M J
MJ
Bergua
M
M
Nagaraj
R H
RH
Prat
J
J
D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000652:urine; D002851:Chromatography, High Pressure Liquid; D003404:Creatinine / Q000652:urine; D003922:Diabetes Mellitus, Type 1 / Q000209:etiology / Q000652:urine*; D005260:Female; D006801:Humans; D006868:Hydrolysis; D015416:Maillard Reaction; D008297:Male; D013058:Mass Spectrometry; D009646:Norleucine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000652:urine; D011758:Pyrroles / Q000378:metabolism / Q000652:urine*; D012015:Reference Standards; D013056:Spectrophotometry, Ultraviolet
D015415:Biomarkers; D011758:Pyrroles; C059571:2-formyl-5-(hydroxymethyl)pyrrole-1-norleucine; D009646:Norleucine; D003404:Creatinine