Pharmacokinetics and tissue distribution of Ebracteolatain A, a potential anti-cancer compound, as determined by an optimized ultra-performance liquid chromatography tandem mass spectrometry method.

Ebracteolatain A is a phloroglucinol derivative from the root of Euphorbia ebracteolata Hayata, a Traditional Chinese Medicine also known as Langdu. It has been shown to have good inhibitory effects in breast cancer cells. In this study, a simple, rapid, sensitive, and specific ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated to study the pharmacokinetics (PKs) and tissue distribution of Ebracteolatain A in rats. Ebracteolatain A and Magnolol (internal standard) were extracted by the simple protein precipitation extraction technique using methanol as the precipitating solvent. Chromatographic separation was performed using the Agilent Poroshell 120 EC-C18 column with a mobile phase of acetonitrile:0.1% formic acid (70:30, v/v). The protonated analyte was quantitated in negative ionization by MS/MS via multiple reaction monitoring mode. The assay exhibited a linear dynamic range of 2-2000 ng/mL for Ebracteolatain A in biological samples. The lower limit of quantitation was 2 ng/mL. Non-compartmental PK parameters indicated that Ebracteolatain A was well absorbed into the systemic circulation. The absolute bioavailability of Ebracteolatain A was greater when administered by intraperitoneal administration than by oral administration. The tissue distribution study showed that Ebracteolatain A was distributed in the heart, liver, spleen, lung, kidney, brain, stomach, intestine, uterus, ovary, and breast after intravenous injection. The results of this study further our understanding of the in vivo anti-cancer activity of Ebracteolatain A, and shed light on pharmacological strategies that may be useful for the development of novel breast cancer therapeutics.

A UPLC-MS/MS method for simultaneous determination of five flavonoids from Stellera chamaejasme L. in rat plasma and its application to a pharmacokinetic study.

Stellera chamaejasme L. has been used as a traditional Chinese medicine for the treatment of scabies, tinea, stubborn skin ulcers, chronic tracheitis, cancer and tuberculosis. A sensitive and selective ultra-high liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the simultaneous determination of five flavonoids (stelleranol, chamaechromone, neochamaejasmin A, chamaejasmine and isochamaejasmin) of S. chamaejasme L. in rat plasma. Chromatographic separation was accomplished on an Agilent Poroshell 120 EC-C18 column (2.1 × 100 mm, 2.7 µm) with gradient elution at a flow rate of 0.4 mL/min and the total analysis time was 7 min. The analytes were detected using multiple reaction monitoring in positive ionization mode. The samples were prepared by liquid-liquid extraction with ethyl acetate. The UPLC-MS/MS method was validated for specificity, linearity, sensitivity, accuracy and precision, recovery, matrix effect and stability. The validated method exhibited good linearity (r ≥ 0.9956), and the lower limits of quantification ranged from 0.51 to 0.64 ng/mL for five flavonoids. The intra- and inter-day precision were both <10.2%, and the accuracy ranged from -11.79 to 9.21%. This method was successfully applied to a pharmacokinetic study of five flavonoids in rats after oral administration of ethyl acetate extract of S. chamaejasme L.