Cryptotanshinone and tanshinone IIA from<i>Salvia milthorrhiza</i>Bunge (Danshen) as a new class of potential pancreatic lipase inhibitors

Abstract

<i>Salvia miltiorrhiza</i> Bunge extract was investigated for the first time for its inhibitory activity against pancreatic lipase (PL), an important enzyme involved in the digestion of dietary fats. It showed a concentration-dependent activity with an IC₅₀ value of 3.54 ± 0.22 mg/mL. Two compounds, cryptotanshinone and tanshinone IIA (the major lipophilic constituents of <i>S. miltiorrhiza</i>), have been selected as potential ligands of PL. Cryptotanshinone showed a higher lipase inhibitory activity (IC₅₀ = 6.86 ± 0.43 µM) compared to the parent tanshinone IIA. Molecular docking studies were undertaken to establish whether a direct interaction of the principal constituents of the <i>S. miltiorrhiza</i> extract with the human pancreatic lipase could be evoked. All these findings provided new insights into the understanding of the interactions between natural constituents of <i>S. miltiorrhiza</i> extract and PL, also suggesting that cryptotanshinone could be used as lead compound for the development of efficacious PL inhibitors.