Oxidative Modifications in Crystallin Proteins and Lens Epithelial Cells Associated with Photosensitized Reactions Mediated by the Major Chromophore Arising from Glucose Degradation

Deleterious effect mediated by glucose degradation, as a parallel pathway to Maillard reaction, was analyzed in terms of the feasibility of inducing photo-crosslinking in isolated bovine crystalline proteins when exposed to ultraviolet A (UVA)-visible light. These experiments showed evidence supporting the generation of a glucose-derived chromophore (GDC). The ability of this chromophore to induce oxidative damage in lens protein and bovine lens epithelial cells (BLEC) was further assessed. The analysis of dityrosine and carbonyl levels in lens proteins irradiated at 5 and 20% O2 indicates the...