Pharmacokinetics of Sijunzi decoction in rat plasma after oral administration using ultra-high-performance liquid chromatography electrospray ionization quadrupole-time of flight mass spectrometry.

Sijunzi decoction (SJZD) is one of the most well-known traditional Chinese herbal formulations. This study elucidates the pharmacokinetics of SJZD in rat plasma after the administration of a single oral dose of 3 mL/kg using ultra-high-performance liquid chromatography electrospray ionization quadrupole-time of flight mass spectrometry (UHPLC-ESI-Q-TOF/MS) with bergapten as an internal standard. The separation was performed on an Agilent Zorbax Eclipse Plus C18 column (2.1 × 50 mm, 1.8 µm) by elution with acetonitrile and water (containing 0.1% formic acid) at a flow rate of 0.3 mL/min. Electrospray ionization in positive and negative ion modes was used to quantify six compounds, with monitored ion m/z values of 249.1397 [M + H]+ and 529.3857 [M + H]+ for atractylenolide III (ATL-III) and pachymic acid (PA), respectively, and m/z of 1107.6638 [M - H]- , 991.5746 [M - H + HCOO]- , 821.3714 [M - H]- , 469.3315 [M - H]- for ginsenoside Rb1, Re, glycyrrhizic acid (GL), and glycyrrhetinic acid (GA), respectively. The calibration curves for ginsenoside Rb1 , Re, ATL-III, PA, GL and GA were 0.0015-0.75, 0.001-0.5, 0.0004-0.2, 0.003-0.9, 0.0015-0.3 and 0.001-1.5 µg/mL, respectively. The intra- and inter-day precisions (RSD) were <14.3%. The rapid, sensitive and specific UHPLC-ESI-Q-TOF/MS method developed and validated in this study was successfully applied to the simultaneous determination of the six components of SJZD using rat plasma for pharmacokinetic studies after oral administration.

CHMP4C Disruption Sensitizes the Human Lung Cancer Cells to Irradiation.

Human lung cancer is highly invasive and the most malignant among human tumors. Adenocarcinoma as a specific type of non-small cell lung cancer occurs with high frequency and is also highly resistant to radiation therapy. Thus, how to avoid radiation resistance and improve radiotherapy effectiveness is a crucial question. In the present study, human lung cancer A549 and H1299 cells were irradiated using γ-rays from a Co60 irradiator. Protein expression was detected by Western blotting. Cell cycle and apoptosis were measured by flow cytometry. Surviving fraction was determined by colony formation assay. γH2AX and 53BP1 foci formation were examined by fluorescence microscopy. In the results, we show that CHMP4C, a subunit of Endosomal sorting complex-III (ESCRT-III), is involved in radiation-induced cellular response. Radiation-induced Aurora B expression enhances CHMP4C phosphorylation in non-small cell lung cancer (NSCLC) cells, maintaining cell cycle check-point and cellular viability as well as resisting apoptosis. CHMP4C depletion enhances cellular sensitivity to radiation, delays S-phase of cell cycle and reduces ionizing radiation (IR)-induced γH2AX foci formation. We found that Aurora B targets CHMP4C and inhibition of Aurora B exhibits similar effects with silencing of CHMP4C in radioresistance. We also confirm that CHMP4C phosphorylation is elevated after IR both in p53-positive and-negative cells, indicating that the close correlation between CHMP4C and Aurora B signaling pathway in mediating radiation resistance is not p53 dependent. Together, our work establishes a new function of CHMP4C in radiation resistance, which will offer a potential strategy for non-small cell lung cancer by disrupting CHMP4C.

Radiosensitizing effect of schinifoline from Zanthoxylum schinifolium Sieb et Zucc on human non-small cell lung cancer A549 cells: a preliminary in vitro investigation.

Schinifoline (SF), a 4-quinolinone derivative, was found in Zanthoxylum schinifolium for the first time. 4-Quinolinone moieties are thought to have cytotoxic activity and are often used as a tubulin polymerization inhibitors, heterogeneous enzyme inhibitors and antiplatelet agents. However, very little information respect to radiosensitization has focused on SF. This work aimed to investigate the radiosensitizing effect of SF on A549 cells. The cell viability results indicated cytotoxicity of SF on A549 cells, with IC50 values of 33.7 ± 2.4, 21.9 ± 1.9 and 16.8 ± 2.2 µg/mL, respectively, after 6, 12, 24 h treatment with different concentrations, and the 10% or 20% IC50 concentration during 12 h was applied in later experiments. The results of cell proliferative inhibition and clonogenic assay showed that SF enhanced the radiosensitivity of A549 cells when applied before 60Co γ-irradiation and this effect was mainly time and concentration dependent. The flow cytometric data indicated that SF treatment before the irradiation increased the G2/M phase, thus improving the radiosensitivity of A549, leading to cell apoptosis. This paper is the first study that describes the in vitro radiosensitising, cell cycle and apoptotic-inducing effects of schinifoline.