A matrix-assisted laser desorption/ionization mass spectrometry study of thenon-enzymatic glycation products of human globins in diabetes

The molecular species present in globins from healthy and diabetic subjects with and without chronic complications have been analyzed by matrix-assisted laser desorption/ionization mass spectrometry. The technique demonstrated the presence of glycated and glyco-oxidated species of both α- and β-globins. Their abundances show a good linear relationship with respect to HbA1c values and with the mean daily plasma glucose levels over the 6 weeks preceding the investigation. Interestingly, slightly different behaviour is observed in the data from patients with and without chronic complications; the plots of HbA1c vs. the abundance of glycated and glyco-oxidated species show different slopes and different intercepts with the y-axis. To investigate this aspect the mean abundances of glyco-oxidated species from healthy subjects and from diabetic patients with and without complications were calculated. Higher values were found for the two last sets of samples, but no significant difference was found between them. These data could indicate different individual proclivities to oxidation and/or different oxidation kinetics related to behavioural and environmental factors.