Objective: An investigation on aldose reductase enzyme (ALR) inhibitory activity of apigenin (API) isolated from Morus indica L. was evaluated by ex vivo and molecular docking studies. Materials and Methods: The inhibitory efficacy of API from M. indica was evaluated against ALR in lens tissue of mice by ex vivo and their binding mechanism through molecular docking was carried out by AutoDock. Results: The API (10-50 μg mL-1) concentration exhibited significant inhibition (p ≤ 0.05) of ALR enzyme in a dose dependent manner with IC50 value of 39.23 μg mL-1. The positive control aminoguanidine (AG) at 10 mM inhibited 42.96% of ALR. The molecular docking studies revealed that API showed better binding energy (-9.15 kJ mol-1) when compared to AG (-3.78 kJ mol-1). Molecular interaction analysis showed that API interrupts the proton donation mechanism which is necessary for the catalytic activity of ALR by forming H-bond with Trp20 (proton donor). Conclusion: The ALR inhibition potential offered by API was further confirmed through molecular docking studies. The present findings support the pharmacological application of API for the treatment of diabetes cataract.
Key words: Mulberry, Antiglycation, Retinopathy, Eye lens.