Detection and determination of glyceraldehyde-derived pyridinium-type advanced glycation end product in streptozotocin-induced diabetic rats.

GLAP, glyceraldehyde-derived pyridinium-type advanced glycation end product (AGE), formed by glyceraldehyde-related glycation, was identified in the plasma protein and the tail tendon collagen of streptozotocin (STZ)-induced diabetic rats. It was detected in the plasma protein and the collagen in diabetic rats by LC-MS and LC-MS/MS analysis, but was not detected in normal rats. In addition, GLAP was formed from glyceraldehyde-3-phosphate (GA3P) with lysine as well as glyceraldehyde (GLA) with lysine in vitro. Accordingly, it is suggested that an increase in the GLAP level reflects an increase in the GLA level and the GA3P level. GLAP might be a biomarker for reduced activity of the glyceraldehyde-related enzymes in the metabolic diseases such as diabetic complications.