Urinary pyrraline as a biochemical marker of non-oxidative Maillard reactions in vivo

Life Sci. 1997;60(4-5):279-87. doi: 10.1016/s0024-3205(96)00628-5.


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.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Biomarkers / urine
  • Chromatography, High Pressure Liquid
  • Creatinine / urine
  • Diabetes Mellitus, Type 1 / etiology
  • Diabetes Mellitus, Type 1 / urine*
  • Female
  • Humans
  • Hydrolysis
  • Maillard Reaction*
  • Male
  • Mass Spectrometry
  • Norleucine / analogs & derivatives*
  • Norleucine / metabolism
  • Norleucine / urine
  • Pyrroles / metabolism
  • Pyrroles / urine*
  • Reference Standards
  • Spectrophotometry, Ultraviolet


  • Biomarkers
  • Pyrroles
  • 2-formyl-5-(hydroxymethyl)pyrrole-1-norleucine
  • Norleucine
  • Creatinine