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The effects of notoginsenoside R-1 on the intestinal absorption of geniposide by the everted rat gut sac model

Authors Sa Chula; Lv Hang; Ba Yinying; Sun Jianning; Shi Renbing

Journal JOURNAL OF ETHNOPHARMACOLOGY , JUN 26 2012,1:142

DOI 10.1016/j.jep.2012.04.027 PubMed 22561891

Abstract Ethnopharmacological relevance: Geniposide is derived from Gardenia jasminoides Ellis (Rubiaceae). Its anti-inflammatory, antithrombotic effects as well as its preventive effect against ischemic stroke have been reported. Radix notoginseng (Chinese name tienchi or sanqi) is the dried root of Panax notoginseng (Burk.) F.H. Chen, an herb noted for its promotion of blood circulation, blood stasis removal and pain alleviation, and has been widely utilized for the prevention and treatment of microcirculatory disturbances in China and other Asian countries for many years. Notoginsenoside R-1 is an effective and structurally representative bioactive constituent of R. notoginseng. In our preliminary study, notoginsenoside R-1 was able significantly to improve the bioavailability of geniposide in beagle dogs, but the underlying mechanisms remain unknown.Materials and Methods: The present study aimed to investigate the intestinal kinetic absorptive characteristics of geniposide as well as the absorptive behavior influenced by the co-administration of notoginsenoside R-1 using an in vitro everted rat gut sac model.Results: The results showed good linear correlation between the geniposide absorption in sac contents and the incubation time from 0 to 120 min. The concentration dependence showed a non-linear correlation between the geniposide absorption and the concentrations 0.356-1.424 mg/mL, the absorption was saturated about 1.424 mg/mL. Notoginsenoside R-1 at 0.1 and 0.2 mg/mL concentrations was able significantly to enhance the absorption of geniposide (1.424 mg/mL) by 1.7- and 1.4-fold. Moreover, verapamil, a well-known P-glycoprotein inhibitor, was able significantly to elevate the absorption of geniposide 2.4-fold. Notoginsenoside RI influenced geniposide''s absorption in a way similar to that of a P-glycoprotein inhibitor.Conclusions: In conclusion, notoginsenoside R-1 significantly enhances the intestinal absorption of geniposide. As for the mechanism underlying the improvement of geniposide''s bioavailability, it is proposed that notoginsenoside R-1 was able to decrease the efflux transport of geniposide by P-glycoproteins. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

Species covered 栀子 Gardenia jasminoides