Integrated pharmacokinetic properties and tissue distribution of multiple active constituents in Qing-Yi Recipe: A comparison between granules and decoction

Qing-Yi Recipe, a classic traditional Chinese medicine (TCM), is widely used for treating acute diseases of the abdomen, especially pancreatitis, the efficacy of which has been demonstrated in more than thirty clinical trials. However, the in-vivo pharmacodynamic material basis for this formula remains unclear. A sensitive and accurate method for quantifying twenty-two potential bioactive constituents of Qing-Yi Recipe in biological samples was developed using liquid chromatography-tandem mass spectrometry (LC-MS/MS), and this method was fully validated. Then, the integrated pharmacokinetic properties of Qing-Yi Recipe and its major metabolites in rats were investigated using the post-listed granules at both dosages. Subsequently, tissue distributions of those constituents in nine organs (especially the pancreas) were determined, and the overall parameters between the two formulations were compared. Though the chemical profiles of the formulas varied across formulations, the overall exposure level was very similar, and baicalin, wogonoside, geniposide, rhein, costunolide, and paeoniflorin were the top six bioactive compounds in the circulation. All twenty-two natural products reached their first peak within 2 h, and several of them exhibited bimodal or multimodal patterns under the complicated transformation of metabolic enzymes, and the parameters of these products markedly changed compared with those of monomers. Diverse metabolites of emodin and baicalin/baicalein were detected in circulation and tissues, augmenting the in vivo forms of these compounds. Finally, the enrichment of tetrahydropalmatine and corydaline in the pancreas were observed and most compounds remained in the gastrointestinal system, providing a foundation basis for their potential regulatory effects on the gut microbiota as well as the intestinal functions. Herein, the pharmacokinetic properties and tissue distribution of multiple potential active constituents in Qing-Yi Recipe were investigated at two dosages, providing a pharmacodynamic material basis of Qing-Yi Recipe for the first time. This investigation is expected to provide a new perspective and reference for future studies on the physiological disposition and potential pharmacodynamic basis of traditional Chinese medicine to treat acute abdomen diseases.