Comparison of pharmacokinetic profiles of Terminalia phenolics after intragastric administration of the aqueous extracts of the fruit of Terminalia chebula and a Mongolian compound medicine-Gurigumu-7.

BACKGROUND

The dried fruit of Terminalia chebula (fructus chebulae) is an important Traditional Medicine used for intestinal and hepatic detoxification. Gurigumu-7 which is made of fructus chebulae and 6 other traditional medicines is one of the most frequently used compound Mongolian and Tibet medicines for liver diseases. Terminalia phenolics are considered as the bioactive constituents of fructus chebulae and consequently of Gurigumu-7.

OBJECTIVE

To compare the pharmacokinetic profiles of Terminalia phenolics after intragastric administration of the aqueous extracts of fructus chebulae and Gurigumu-7 and to evaluate the possible influence of intestinal bacterial metabolism on these pharmacokinetic profiles.

METHODS

An ultra performance liquid chromatography with triple quadrupole mass spectrometry method was established and validated for simultaneously determining the pharmacokinetic profiles of seven Terminalia phenolics after intragastric administration of pure compounds, fructus chebulae extract, and Gurigumu-7 extract. In vitro rat fecal lysates experiments were carried out to explore the metabolic discrepancy between fructus chebulae and Gurigumu-7.

RESULTS

Seven Terminalia phenolics were detected in rat plasma after intragastric administration of the aqueous extracts of fructus chebulae and Gurigumu-7. Administration of Gurigumu-7 could promote the absorption and increase the Cmax and AUC values of these phenolic constituents compared to fructus chebulae administration. The fecal lysates studies showed that the Terminalia phenolics in Gurigumu-7 were less rapidly bio-transformed than those in fructus chebulae. This may be a contributing factor to the pharmacokinetic discrepancy between the phenolics in fructus chebulae and Gurigumu-7.

CONCLUSIONS

Administration of Gurigumu-7 could increase the absorption of Terminalia phenolics through slowing down the intestinal bacteria metabolism. These results provide, in part, an in vivo rationale for the formulation of the traditional Mongolia / Tibet medicine, Gurigumu-7.