Protein glycation and oxidation inhibitory activity of Centella asiatica phenolics (CAP) in glucose-mediated bovine serum albumin glycoxidation

The study aimed to evaluate the inhibitory effects of Centella asiatica phenolics (CAP) on bovine serum albumin glycoxidation in a BSA-glucose model in vitro. The impact of the phenolic extract on the formation of total fluorescent advanced glycation end products (AGEs) and Amadori adducts were determined. Dityrosine, N-formylkynurenine, kynurenine and protein-carbonyls were quantified as markers of protein oxidation. Protein structural perturbations were determined by Congo red binding and FTIR analysis. Chemical characterization and CAP phytoconstituent profile was obtained by colorimetric and UHPLC-ESI-qTOF-MS analysis, respectively. Our data show that CAP attenuated the formation of fluorescent AGEs (38.5%), Dityrosine (44.6%), N-formylkynurenine (42.9%), Amadori products, and resisted structural alterations of BSA subjected to glycation. These effects could be due to the antioxidant and radical scavenging activities of CAP mediated by the presence of phenolics and triterpenoids. The results collectively suggest that CAP possesses antiglycative properties with potentials for nutraceutical applications.

Keywords: AGEs; Advanced glycation end products; Antioxidant activity; Centella asiatica; Phenolics; UHPLC-ESI-QTOF-MS.