biostudies-literatureUnknown26Shigeta TReducing sugars and reactive aldehydes, such as glyceraldehyde, non-enzymatically react with amino or guanidino groups of proteins to form advanced glycation end-products (AGEs) by the Maillard reaction that involves Schiff base formation followed by Amadori rearrangement. AGEs are found relatively in abundance in the human eye and to accumulate at a higher rate in diseases that impair vision such as cataract, diabetic retinopathy or age-related macular degeneration. We identified two novel AGEs of pyrrolopyridinium lysine dimer derived from glyceraldehyde, PPG1 and PPG2, in the Maillard reaction of <i>N</i> ^α-acetyl-l-lysine with glyceraldehyde under physiological conditions. Having fluorophores similar to that of vesperlysine A, which was isolated from the human lens, PPGs werBiochemistry and biophysics reports100963https://www.ebi.ac.uk/biostudies/studies/S-EPMC7960790biostudies-literatureGlyceraldehyde-derived advanced glycation end-products having pyrrolopyridinium-based crosslinks.PMC7960790Sasamoto KShigeta TYamamoto TfalseGlyceraldehyde-derived advanced glycation end-products having pyrrolopyridinium-based crosslinks.Reducing sugars and reactive aldehydes, such as glyceraldehyde, non-enzymatically react with amino or guanidino groups of proteins to form advanced glycation end-products (AGEs) by the Maillard reaction that involves Schiff base formation followed by Amadori rearrangement. AGEs are found relatively in abundance in the human eye and to accumulate at a higher rate in diseases that impair vision such as cataract, diabetic retinopathy or age-related macular degeneration. We identified two novel AGEs of pyrrolopyridinium lysine dimer derived from glyceraldehyde, PPG1 and PPG2, in the Maillard reaction of <i>N</i> ^α-acetyl-l-lysine with glyceraldehyde under physiological conditions. Having fluorophores similar to that of vesperlysine A, which was isolated from the human lens, PPGs wer2021-01-01T00:00:00Z2021 Jul2025-04-20T02:28:53.748Z2025-04-20T02:28:53.748ZS-EPMC79607903374843710.1016/j.bbrep.2021.100963