Exploring the effect of salvianolic acid C on α-glucosidase: Inhibition kinetics, interaction mechanism and molecular modelling methods

Publication date: Available online 15 January 2019Source: Process BiochemistryAuthor(s): Hongjin Tang, Fei Ma, Dongsheng Zhao, Zhenglian XueAbstractα-Glucosidase has emerged as an important target for the therapy of type 2 diabetes mellitus. In our previous study, the natural product salvianolic acid C was found to present a potent α-glucosidase inhibitory activity, whereas the interaction mechanisms are still not clear. Herein, an integrated approach consisting of inhibition kinetics, multi-spectroscopic methods and molecular modelling was applied to investigate the interaction mechanism between salvianolic acid C and α-glucosidase. As a result, salvianolic acid C showed a potent α-glucosidase inhibitory activity with IC50 of 3.03 ± 0.27 μM in a mixed-competitive manner. The activity of α-glucosidase was significantly inactivated by salvianolic acid C with the first-order reaction. The fluorescence assay suggested that salvianolic acid C presented a strong fluorescence quenching effect in a static quenching mechanism and the hydrophobic interaction was demonstrated to be the predominant driving force. The synchronous fluorescence and FT-IR spectra indicated that salvianolic acid C could induce the rearrangement and conformational changes of the enzyme. Additionally, molecular modelling studies further validated that salvianolic acid C could bind to the active center of α-glucosidase through hydrophobic interaction and hydrogen bonds. Such findings provide some ...
Source: Process Biochemistry - Category: Biochemistry Source Type: research