A validated LC-MS/MS method for the determination of specnuezhenide and salidroside in rat plasma and its application to a pharmacokinetic study

Gut microbiota-based pharmacokinetic-pharmacodynamic study and molecular mechanism of specnuezhenide in the treatment of colorectal cancer targeting carboxylesterase

Specnuezhenide (SNZ) is among the main components of Fructus Ligustri Lucidi, which has anti-inflammation, anti-oxidation, and anti-tumor effect. The low bioavailability makes it difficult to explain the mechanism of pharmacological effect of SNZ. In this study, the role of the gut microbiota in the metabolism and pharmacokinetics characteristics of SNZ as well as the pharmacological meaning were explored. SNZ can be rapidly metabolized by the gut microbiome, and two intestinal bacterial metabolites of SNZ, salidroside and tyrosol, were discovered. In addition, carboxylesterase may be the main intestinal bacterial enzyme that mediates its metabolism. At the same time, no metabolism was found in the incubation system of SNZ with liver microsomes or liver homogenate, indicating that the gut microbiota is the main part involved in the metabolism of SNZ. In addition, pharmacokinetic studies showed that salidroside and tyrosol can be detected in plasma in the presence of gut microbiota. Interestingly, tumor development was inhibited in a colorectal tumor mice model administered orally with SNZ, which indicated that SNZ exhibited potential to inhibit tumor growth, and tissue distribution studies showed that salidroside and tyrosol could be distributed in tumor tissues. At the same time, SNZ modulated the structure of gut microbiota and fungal group, which may be the mechanism governing the antitumoral activity of SNZ. Furthermore, SNZ stimulates the secretion of short-chain fatty acids by intestinal flora in vitro and in vivo. In the future, targeting gut microbes and the interaction between natural products and gut microbes could lead to the discovery and development of new drugs.

The Current Application of LC-MS/MS in Pharmacokinetics of Traditional Chinese Medicines (Recent Three Years): A Systematic Review

BACKGROUND

With significant clinical effects, traditional Chinese medicine (TCM) has been attracting increasing interest of the world's scientific community. However, TCM contains immense amounts of chemical components. It is a great challenge to objectively evaluate the correlation between the in vivo process and the therapeutic effect of TCM. The purpose of this systematic review was to summarize the recent investigation (from 2017 to 2019) on preclinical pharmacokinetics (PK) of TCM via liquid chromatography coupled with mass spectrometry (LC-MS/MS).

METHODS

We reviewed the published articles regarding the PK of TCM by LC-MS/MS. In addition, we summarized information on PK parameter of bioactive components, single herb and traditional Chinese medicine prescriptions.

RESULTS

The vast majority of literature on preclinical PK of TCM uses single oral administration, the biological matrix is mostly rat plasma, and the main PK parameters include AUC, Cmax, Tmax and T1/2, etc. Conclusion: Although LC-MS/MS can be used for high-throughput analysis, the characterization of in vivo processes of TCM still has a long way. With the advantages of high sensitivity, high specificity and simple operation, the increasingly mature LC-MS/MS technology will play an important role in the PK study of TCM.