Comparative study of different glycating agents on human plasma and vascular cells

Diabetic complications are associated with the glycation and formation of advanced glycation end products (AGEs) which leads to structural modifications of biomolecules further affecting cells. Carbonyl compounds such as methylglyoxal and glyceraldehyde-3-phosphate are highly reactive and form an elevated amount of AGEs as compared to glucose and fructose. The investigation of glycation modifications by different compounds may be important to assess the specific pattern of biomolecular and cellular modifications and compare their glycation potential. The present work aims to comprehensively and comparatively examine the effect of glycating agents (glucose, fructose, ribose, methylglyoxal, and glyceraldehyde) on plasma, erythrocytes, platelets, and blood DNA. Glycation of plasma, cells, and DNA was initiated by incubating them with glycating agents for 24-48 h at 37 °C. Negative control samples (without glycating agents) were maintained simultaneously. After treatment, plasma and DNA samples were dialyzed and cell lysate was prepared. Markers of glycation (fructosamine), structural modifications (free amino, β-amyloid, absorption spectra), antioxidant indices (catalase activity, glutathione) and erythrocyte hemolysis were estimated. In the presence of glycating agents, there was a significant increase in the formation of fructosamine, structural modification markers and depletion in antioxidant indices. Overall results suggest that among all glycating agents; methylglyoxal and glyceraldehyde have more potency of glycation induced structural modifications in plasma and vascular cells. This indicates the specific glycation modifications in plasma and vascular cells by various glycating agents may be investigated further for controlling diabetic pathological changes.