Pharmacokinetics, tissue distribution, and excretion of anthraquinones and their glucuronide metabolites from raw and steamed pieces of Rhei Radix et Rhizoma extract in constipation rats

Under the guidance of national policies and driven by innovations in analytical technologies, the volume of publications on the processing mechanism study of traditional Chinese medicine (TCM) has been increasing annually. This sustained surge in scientific interest has progressively unveiled the scientific connotations of the classical TCM theory of "reducing toxicity and enhancing efficacy," yet it still faces the challenge of insufficient research depth. Rhubarb (Rhei Radix et Rhizoma) is a representative herb exemplifying the TCM processing principle of "different therapeutic effects between raw and processed forms." Its wine-processing leads to an attenuated purgative effect, making it a paradigmatic case for elucidating the mechanisms of TCM processing.

Professor Ying Liu, grounded in the discipline of TCM processing study, selected rhubarb pieces as the research subject. The study aimed to establish a pharmacokinetic-based research paradigm to clarify the scientific principles underlying TCM processing. Specifically, it not only monitored absorption, distribution, and excretion profiles of prototype anthraquinones but also determined that of their predominant in vivo forms, i.e., glucuronide metabolites. Unlike prior studies that analyzed either only the prototype compounds or partial in vivo process, this work delved deeper by focusing on the major existent forms, glucuronide metabolites and prototype components, and established a novel analytical method enabling simultaneous quantification of both prototype compounds and their glucuronide metabolites. Furthermore, it comprehensively characterized the systemic dynamic changes of these components following oral administration between raw and steamed rhubarb in rats. This study thus provides a more comprehensive pharmacokinetic research paradigm for investigating the in vivo process of bioactive components, laying scientific research foundation for revealing the processing mechanism of rhubarb.

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Pharmacokinetics, tissue distribution, and excretion of anthraquinones and their glucuronide metabolites from raw and steamed pieces of Rhei Radix et Rhizoma extract in constipation rats

https://journals.lww.com/stcm/fulltext/2025/09000/pharmacokinetics,_tissue_distribution,_and.6.aspx