TABLE 2.
Early and advanced glycation products annotated in in vitro glycation mixtures
Incubations were performed for 42 days at 22 °C under continuous shaking; analysis was performed by UPLC-QqTOF-MS operating in the positive ion mode. CMA, Nϵ-carboxymethylarginine; ArgPyr, argpyrimidine; GLAP, glyceraldehyde-derived pyridinium compound. MGD-HI, methylglyoxal-derived dihydroxyimidazolidine; GD-HI, glyoxal-derived dihydroxyimidazolidine.
| Label | Producta | Reaction partnerb | m/z[M + 2H]2+obsc | tR | Residue in the position 6 | Δm |
|---|---|---|---|---|---|---|
| min | ||||||
| 1-1 | Ac-AFGSAKASGA-NH2 | 454.2316 | 1.9 | Lysine | ||
| 1-2 | Ac-AFGSA[pyrraline]ASGA-NH2 | Ery | 574.2633 | 1.9 | 5-(Hydroxymethyl)-1H-pyrrole-2-carbaldehyde | 108.021 |
| 1-3 | Ac-AFGSA[GLAP]ASGA-NH2 | Glal-P | 589.7723 | 2.0 | 1- (5-Acetylamino-5-carboxypentyl)-3-hydroxy-5-hydroxymethylpyridinium | 109.0284 |
| 1-4 | Ac-AFGSA[CEL]ASGA-NH2 | Dap | 490.2422 | 2.8 | Nϵ-Carboxyethyllysine | 72.0211 |
| 1-5 | Ac-AFGSAK[triose]ASGA-NH2 | Dap | 490.2422 | 2.0 | N-Triosyllysine | 72.0212 |
| 1-6 | Ac-AFGSA[CML]ASGA-NH2 | Rul | 483.2344 | 2.6 | Nϵ-Carboxymethyllysine | 58.0055 |
| 1-7 | Ac-AFGSAK[hexose]ASGA-NH2 | Fru | 535.2581 | 1.8 | N-Hexosyllysine | 162.0529 |
| 1-8 | Ac-AFGSAK[pentose]ASGA-NH2 | Rib | 520.2528 | 1.9 | N-Pentosyllysine | 132.0423 |
| 1-9 | Ac-AFGSAK[tetrose]ASGA-NH2 | Fru | 505.2475 | 1.9 | N-Tetrosyllysine | 102.0317 |
| 2-1 | Ac-AFGSARASGA-NH2 | 468.2347 | 2.0 | Arginine | ||
| 2-2 | Ac-AFGSA[Glarg]ASGA-NH2 | Ery | 488.2322 | 2.0 | 1-(-4-Amino-4-carboxybutyl)2-imino-5-oxoimidazolidine | 39.9949 |
| 2-3 | Ac-AFGSA[MG-H]ASGA-NH2 | Dap | 495.2400 | 2.3 | Methylglyoxal-derived hydroimidazolone | 54.0105 |
| 2-4 | Ac-AFGSA[CMA/GD-HI]ASGA-NH2 | Rul | 497.2375 | 2.4 | Nδ-Carboxymethylarginine/Nδ- (3.4-dihydroxy-1-imidazolidin-2-yl)ornithine | 58.0055 |
| 2-5 | Ac-AFGSA[CEA/MGD-HI]ASGA-NH2 | Dap | 504.2453 | 2.6 | Nδ-Carboxyethylarginine/2-amino-5-(4,5-dihydroxy-5-methyl-4,5-dihydro-1H-imidazol-2-ylamino)pentanoic acid | 72.0211 |
| 2-6 | Ac-AFGSA[ArgPyr]ASGA-NH2 | Glal-P | 508.2478 | 3.2 | Nδ-(5-Hydroxy-4,6-dimethylpyrimidine-2-yl)-l-ornithine | 80.0262 |
a The analytes are listed in the order of their retention times. AGE-modified lysyl and arginyl residues are marked with brackets; Amadori or Heyns products on lysyl (K) residues are subscript with brackets.
b Abbreviation of the sugar used in the incubation where annotation of the analyte was performed.
c All analytes were annotated with mass accuracy ≤3ppm; XICs were calculated for m/z ± 0.02.