Inhibitory Activity and Docking Studies of Cathepsin V for Isoflavanoids from Dalbergia miscolobium Benth

Plant extracts from Dalbergia genus have demonstrated a wide range of biological activities including analgesic, antidiabetic, anti-inflammatory and antimicrobial. In this work, the chemical study of the extracts from the leaves and branches of Dalbergia miscolobium led to the identification of five isoflavonoids: prunetin, di- O -methyldaidzein, 8- O -methylretusin, duartin and sativan by means of nuclear magnetic resonance data. The inhibition activity of these isoflavonoids were screened against cathepsin V at concentration of 100 µM. Duartin and sativan showed remarkable activity against cathepsin V displaying inhibition values of 89% and 88%, respectively. In addition, docking simulations to predict the binding mode in this protein were performed and the results showed that the duartin is nicely bound to the cathepsin V and stabilized by two hydrogen bonds. The isoflavans duartin and sativan showed an important inhibition percentage of cathepsin V, which can be considered as targets into cathepsin V inhibitors investigation and further chemical study of Dalbergia species may afford novels isoflavonoids cathepsin inhibitors.