Clove bud extract inhibits glycation of bovine serum albumin: Insights from in vitro and molecular dynamics simulation analysis

Abstract

Background: Glycation is a non-enzymatic reaction between amino groups within proteins and reducing sugars, leading to advanced glycation end products (AGEs). AGEs can induce protein cross-linking and accumulate in various tissues. Their buildup contributes to complications associated with chronic disease. Although antiglycation agents like aminoguanidine are well documented, there is a significant need for more effective AGE inhibitors to address various pathogeneses and complications. Syzygium aromaticum, commonly known as clove, has several medicinal properties, including antimicrobial and antioxidant effects that contribute to reduced oxidative stress. However, its impact on glycation and related biochemical parameters has not been thoroughly investigated. 

Objectives: This study aims to evaluate the impact of clove bud extract on BSA glycation and elucidate its mechanism of action through molecular simulations.

Methods: The antiglycation effects of clove bud extract were evaluated by quantifying glycation-induced changes in BSA structure and aggregation following glucose-mediated glycation and subsequent treatment with varying extract concentrations. UV spectroscopy and fluorescence-based assays (Congo red and Thioflavin T) were used to assess these changes. At the same time, molecular docking and dynamics simulations explored the underlying molecular interactions between clove bud components and BSA.

Results: The results demonstrated that clove bud extract at a 600 µg/ml concentration significantly decreased the browning intensity by 54.38%. When combined with glycated BSA, the extract reduced the aggregation index and mitigated glycation-induced alterations in BSA's secondary structure, indicating its potential to inhibit glycation and prevent AGE formation. Increasing the dosage of clove bud extract resulted in a decrease in Thioflavin T-specific fluorescence in the samples. Molecular docking studies revealed several compounds within the clove extract interact with glycation-prone residues on BSA, specifically lysine and arginine. Molecular simulation studies further confirmed that all tested compounds form stable complexes with BSA when simulated under aqueous conditions, which mirror physiological environments. 

Novelty of the Study: This study presents novel findings on the inhibitory effects of clove bud extract on the glycation process of bovine serum albumin (BSA), demonstrating its potential as a natural inhibitor of glycation.

Conclusion: These findings underscore the potential of clove bud as a natural inhibitor of glycation and glycation-induced protein aggregation.

Keywords: Clove; glycation; Oxidative stress, aggregation; BSA; molecular docking; molecular dynamics simulation, Pathogenesis.