Determination of toosendanin in rat plasma by ultra‐performance liquid chromatography–electrospray ionization–mass spectrometry and its application in a pharmacokinetic study

Abstract

Toosendanin (TSN) is a major triterpenoid existing in Melia toosendan, which has been used as a digestive tract parasiticide and insecticide but with serious hepatotoxicity. An ultra-performance liquid chromatography-electrospray ionization-mass spectrometry method was developed for determination of TSN in rat plasma. Plasma samples were separated on Acquity UPLC(TM) BEH C(18) column with acetonitrile and water as flow phase by gradient elution and determined by quadrupole mass spectrometer in negative selective ion monitoring mode. Usolic acid was used as internal standard. The calibration curves were linear over 0.02-3.0 µg/mL for TSN with a lower limit of quantification (LLOQ) of 20 ng/mL in rat plasma. The extraction recoveries of TSN were within 74.3-80.7% with an accuracy of 94.5-108.9%. The intra- and inter-day precision values of the assay at three quality control levels were 8.8-13.8% and <13.9% at LLOQ level, respectively. The method was successfully applied to a pharmacokinetic study of TSN in rats after a single intravenous and oral administration of 2 and 60 mg/kg. The shorter T(max) , higher V(d) and Cl of TSN after oral administration indicated that TSN could be absorbed, distributed and eliminated quickly in rats in vivo. The absolute bioavailability of TSN after oral administration was 9.9%.

Metabolite Analysis of Toosendanin by an Ultra-High Performance Liquid Chromatography-Quadrupole-Time of Flight Mass Spectrometry Technique

“…And good accuracies of 99.8, 102.2, and 99.2% were also achieved at all three concentrations been examined. The remaining amount of toosendanin at different reaction times was quantified, and the results indicated that toosendanin could be rapidly metabolized within 30 min, and hardly detected at 120 min (Figure S2), which was consistent with the pharmacokinetic results in rat [10].…”

“…Previously, two LC-MS analytical methods were reported to quantify toosendanin in medicinal herbs [12] and in rat plasma [10], respectively. However, due to its limitation of using single stage MS ion, [M+Na] + or [M−H] − , for quantification, the sensitivity and dynamic linear range were unsatisfactory.…”

“…Also, if present, the corresponding molecular targets need to be clarified and identified. Previous pharmacokinetic research on toosendanin in rats demonstrated that toosendanin could be quickly absorbed after oral administration and the absolute bioavailability was lower than 10% [10], which implies that the hepatotoxicity might be induced by its metabolites. However, there are no reports of in vitro or in vivo studies trying to identify its metabolites.…”

Determination of toosendanin and trans‐anethole in Fructus Meliae Toosendan and Fructus Foeniculi by HPLC–MS/MS and GC–MS/MS in rat plasma and their potential herb–herb interactions

“…However, it has been frequently reported to induce severe liver injury during clinical practice and empirical research in recent years (Yang et al, 2019; Yuen et al, 2010; J. Zheng et al, 2015), and liver cell necrosis was proven to be the main liver toxicity mechanism of CLZ (J. Zheng et al, 2015; Jie Zheng, Yu, Chen, Lu, & Fan, 2018). Toosendanin (TSN) has been identified as the main active component in CLZ and is also the main toxic compound that induces liver injury (Eng Shi & Choon Nam, 2010; X. Wang, Wang, & Wang, 2013; Figure 1).…”

Optimization of extraction and analytical protocol for mass spectrometry‐based metabolomics analysis of hepatotoxicity

“…As a traditional Chinese medicine, TSN has unique bioactivities and great therapeutic value, as in the inhibition of hepatitis C virus infection and suppression of the proliferation of various human cancer cell lines (Wang, Wang, & Wang, 2013). However, owing to a furan ring in its chemical structure, TSN can cause significant hepatotoxicity (Lu et al, 2016;Stepan et al, 2011).…”