Role of Ascorbic Acid and Pyridoxal-5-Phosphate in the Prevention of Glucose-Induced Damage of Protein and DNA

Objective: This study aims to assess the interaction of ascorbic acid (AA) and pyridoxal-5-phosphate (PLP) with serum protein for binding affinity. These vitamins are investigated for the glucose-induced glycation products for 28 days at 37 °C. Methods: The interaction of AA-BSA and PLP-BSA complexes was analysed spectroflurometrically. The glycation process was checked by spectroscopically measuring fructosamine content, carbonyl content, and total fluorescent advanced glycated end products (AGEs). The aggregation of amyloid β-structure was measured with Congo red and Thioflavin-T dye assays in glycation-induced BSA. The damage prevention of DNA strands was analyzed using electrophoresis. Results: Both, ascorbic acid and pyridoxal-5-phosphate showed the quenching of fluorescence of AA-BSA and PLP-BSA complexes. Pyridoxal-5-phosphate showed more binding affinity than ascorbic acid and found a K b value of 5.63 × 104 M −1 . Pyridoxal-5-phosphate showed suppression of generated Amadori products (45%), carbonyl content (33.54%), and total fluorescent AGEs (36.32%) in the glycation system. However, ascorbic acid caused a reduction in the total fluorescent AGEs by 24.55%. The glycation-induced aggregation in the presence of AA and PLP was prevented by 23.91% and 31.26%. Both vitamins could prevent the DNA breaks, which were caused due to glycoxidation. Conclusion: These findings suggest that pyridoxal-5-phosphate showed more binding affinity, anti-glycation, and anti-aggregation properties than ascorbic acid.