Coexisted components of Salvia miltiorrhiza enhance intestinal absorption of cryptotanshinone via inhibition of the intestinal P-gp

Cryptotanshinone, derived from the roots of Salvia miltiorrhiza Bge and Salvia przewalskii Maxim, is the major active component and possesses significant antibacterial, antidermatophytic, antioxidant, antiinflammatory and anticancer activities. The objective of this study was to investigate the intestinal absorptive characteristics of cryptotanshinone as well as the absorptive behavior influenced by coadministration of the diterpenoid tanshinones and danxingfang using an in vitro everted rat gut sac model. The results showed a good linear correlation between cryptotanshinone of absorption and the incubation time from 10 to 70 min. The concentration dependence showed that a non-linear correlation existed between the cryptotanshinone absorption and the concentration at 100 mu g/ml. Coexisting diterpenoid tanshinones and danxingfang could significantly enhance the absorption of cryptotanshinone. Coexisting diterpenoid tanshinones and danxingfang, which influenced cryptotanshinone's absorption, manifested as similar to that of the P-glycoprotein inhibitor. The underlying mechanism of the improvement of oral bioavailability was proposed that coexisting diterpenoid tanshinones and danxingfang could decrease the efflux transport of cryptotanshinone by P-glycoprotein. (C) 2012 Elsevier GmbH. All rights reserved.