Qualitative and Quantitative Analysis of Glycated Proteins in Human Plasma by Glucose Isotopic Labeling with 13C6-Reducing Sugars

Abstract

Glucose is the predominant source of energy in cells. However, a chronic high glucose exposure of proteins modifies a number of biological pathways, known as glucotoxicity. Several studies have suggested that this impaired protein function is associated in part to protein glycation. However, despite the evidence of this glucotoxicity on tissues and cells, the exact mechanisms underlying the loss of protein function by glycation are not well understood. Strategies that will allow the discovery of the identity and function of the glycated plasma proteins generated by chronic hyperglycemia would be of a considerable help to further understand the underlying mechanisms implicated in protein dysfunction associated with glucotoxicity. The present chapter describes an innovative and interdisciplinary proteomics strategy to achieve a comprehensive identification and quantification of glycated proteins in plasma. This should provide new molecular insights into protein glycation mechanisms and identify new targets to improve the subsequent defective protein function.

Non‐enzymatic glycation and glycoxidation protein products in foods and diseases: An interconnected, complex scenario fully open to innovative proteomic studies

“…Very recently, the use of the Orbitrap hybrid mass analyzer enabled the application of a novel ion dissociation mode for glycation analysis (Priego‐Capote et al, ). This is the higher energy collisional dissociation (HCD) mode, which is characterized by its performance in an additional octopole collision cell attached to the C‐trap using N 2 as the collision gas.…”

“…Optimum collision energies for identification were used for each case (35% and 50% for CID and HCD, respectively). Reproduced with permission from Priego‐Capote et al (). Copyright 2011, Springer.…”

Development of Diagnostic Fragment Ion Library for Glycated Peptides of Human Serum Albumin: Targeted Quantification in Prediabetic, Diabetic, and Microalbuminuria Plasma by Parallel Reaction Monitoring, SWATH, and MSE

“…Thus, to assess the degree of glycation at a given pathophysiological condition, precise identification of glycation becomes critical. In this regard, a stable-isotope-dilution tandem mass spectrometry method was employed for simultaneous analysis of CML and CEL in hydrolysates of plasma proteins (28), and 13 C6-glucose was utilized to quantify glycated proteins in the plasma and erythrocytes (29,30). In a recent study, the glycationsensitive peptides of HSA that could serve as markers for early diagnosis of type 2 diabetes were quantified by using an MS-based 18 O-labeling technique (31).…”

Glycated proteome: From reaction to intervention

“…Mass spectrometry‐based studies have used neutral loss and electron transfer dissociation (ETD)‐based approaches for characterization of glycation modifications . Isotope labeling with 3 C 6 ‐reducing sugars has been used for the analysis of glycated proteins from human plasma . Recently, glycating activities of seven important AGE‐precursors, including glucose and their reactive carbonyl compounds, glucosone, 3‐DG, 3‐deoxygalactosone, 3,4‐dideoxyglucosone‐3‐ene, methylglyoxal, and glyoxal were determined by multiple reaction monitoring using ultra‐HPLC/MS/MS .…”