Studying on the effect and mechanism of four natural flavonoids in non-enzymatic glycation of bovine serum albumin based on spectroscopy and molecular simulation

Diabetes is a chronic disease, and long term hyperglycemia and oxidative stress in diabetes patients will lead to non-enzymatic glycosylation of proteins and eventually produce advanced glycation end products (AGEs). The non-enzymatic glycosylation of proteins and the formation and accumulation of AGEs in blood vessels and tissues are closely related to the complications of diabetes. Here, the anti-glycation mechanisms of four natural flavonoids, baicalein (BA), baicalin (BE), catechin (CT), and proanthocyanidinB2 (PB2), are studied using a bovine serum albumin (BSA) glycosylation model. The results show that fructose may induce non-enzymatic glycosylation of BSA with a significant increase in glycation stage products, increase aggregation and decrease hydrophobicity. In the presence of reactive oxygen species H 2 O 2 , it exacerbates non-enzymatic glycosylation of BSA and causes more severe damage to its function and structure. BA, BE, CT, and PB2 may inhibit non-enzymatic glycosylation of BSA, exert anti-glycosylation stage products, anti-aggregation, inhibit hydrophobicity reduction, and protect BSA structure. BA/BE/CT/PB2 forms a complex with BSA to statically quench the endogenous fluorescence of BSA. Molecular docking and molecular dynamics simulation are used to further confirm that the main binding forces between BSA and flavonoids are hydrophobic, but there are also hydrogen bonding and electrostatic interactions.