Amino Acids

, Volume 46, Issue 2, pp 311–319

Detection of diabetic nephropathy from advanced glycation endproducts (AGEs) differs in plasma and urine, and is dependent on the method of preparation

Authors

    • Section of Diabetes, Endocrinology, and MetabolismDartmouth-Hitchcock Medical Center
    • Department of Medicine/EndocrinologyGeisel School of Medicine at Dartmouth
  • Scott K. Howell
    • Department of Medicine/EndocrinologyGeisel School of Medicine at Dartmouth
  • Greg Russell
    • Department of Biostatistical SciencesWake Forest University
  • Michael E. Miller
    • Department of Biostatistical SciencesWake Forest University
  • Stephen S. Rich
    • Center for Public Health GenomicsUniversity of Virginia
  • Michael Mauer
    • Department of Pediatrics and MedicineUniversity of Minnesota
Original Article

DOI: 10.1007/s00726-013-1533-x

Cite this article as:
Beisswenger, P.J., Howell, S.K., Russell, G. et al. Amino Acids (2014) 46: 311. doi:10.1007/s00726-013-1533-x

Abstract

Increased advanced glycation endproducts (AGEs) and oxidation products (OPs) have been proposed as pathogenic for diabetic nephropathy (DN). We investigated the relationship between AGEs and OPs measured in different plasma and urine preparations, and progression of DN in 103 young, normoalbuminuric, normotensive participants with type 1 diabetes in the Natural History of Diabetic Nephropathy Study. The primary endpoint was electron microscopy-measured change in glomerular basement membrane (GBM) width from baseline to 5 years; change in mesangial fractional volume was a secondary endpoint. Fast progressors (FP) were defined as the upper quartile (n = 24) of rate of GBM thickening; slow progressors (SP) were the remainder (n = 79). Four AGEs [3-deoxyglucosone and methylglyoxal hydroimidazolones (DG3H1, MGH1) and carboxymethyl and ethyl lysine (CML, CEL)], and two oxidation products methionine sulfoxide and aminoadipic acid were measured by liquid chromatography, triple quadrupole mass spectrometry. Measurements were done on 10 K plasma filtrates and plasma proteolytic digests (PPD) at year 5, and at four time points over 5 years for urinary 10 K filtrates. Urinary filtrate CEL levels were significantly higher in FP, but not after adjustment for HbA1c, sex, and duration of diabetes. MGHI, CEL, and CML plasma filtrate levels were significantly higher in FP relative to SP (p < 0.05). In PPD, only MGHI showed borderline significantly higher levels in FP relative to SP (p = 0.067), while no other product showed correlation. AGE and OP measurements were not correlated with mesangial expansion. In plasma filtrates, HbA1c at year 5 accounted for 4.7 % of the variation in GBM width. The proportion of variation in GBM width was increased to 11.6 % when MGHI, CEL, and CML were added to the model (6.9 % increase).

Keywords

Diabetic nephropathy Diabetic complications Advanced glycation endproducts Oxidation end-products Glycation Oxidation Biomarkers Mass spectrometry

Copyright information

© Springer-Verlag Wien 2013