Structural elucidation of two new megastigmane glycosides from the leaves of Aquilaria sinensis / 中国天然药物

The present study was designed to determine the chemical constituents and identify new components of the leaves of Aquilaria sinensis (Lour.) Gilg. The compounds were isolated and purified by repeated silica gel, Sephadex LH-20, and ODS column chromatography and their structures were elucidated by NMR and HR-ESI-MS spectrometry. Eight megastigmane glycosides and two cucurbitacins were isolated and identified as (9S) megastigma-4,7-diene-2,3,9-triol 9-O-β-D-glucopyranoside (1), (9S) megastigma-4(13),7-diene-3,6,9-triol 9-O-β-D-glucopyranoside (2), macarangloside D (3), corchoionoside C (4), staphylionoside H (5), (+) 3-oxo-α-ionol-β-D-glucopyranoside (6), (-) 3-oxo-α-ionol-β-D-glucopyranoside (7), citroside B (8), 2-O-β-D-glucopyranosyl cucurbitacin I (9), bryoamaride (10). Compounds 1 and 2 were newly identified megstigmane glucosides and reported from this genus for the first time.

Study on in vivo pharmacokinetics of cucurbitacin injection in rats / 中国中药杂志

To establish a method for the determination of cucurbitacin in plasma samples, in order to study the in vivo pharmacokinetic characteristics of cucurbitacin in rats. Rats were intravenously injected with cucurbitacin. With diphenhydramine as the internal standard (IS), the plasma concentrations of cucurbitacin in rat plasma at different time points were determined by liquid chromatography tandem mass spectrometry (LC-MS/MS). With electrospray ionization source, the positive ion detection in the multiple reaction monitoring mode was conducted to determine the ion-pairs for target compound and IS were m/z 503.2/113.1 and m/z 256.0/167.2, respectively. Agilent ZOBAX SB-C18 column (2.1 mm x 50 mm, 1.8 microm) was adopted and eluted with methanol and 0.1% formic acid (55:45), and the flow rate was 0.2 mL x min(-1). DAS 2.0 software was applied to fit the blood concentration and calculate corresponding pharmacokinetic parameters. The rats were intravenously injected with cucurbitacin at the concentration of 3.0 mg x kg(-1). The target blood quality concentration show good linear relations within the range of 10.5-3 150 microg x L(-1) (R2 = 0.996), the lower limit of the standard curve was 10.5 microg x L(-1), and the signal to noise ratio S/N = 12. Intra- and inter-day precisions RSD was less than 6.9% and 14%, respectively; The accuracy RE ranged between 0.20% and 3.7%; The extraction recoveries ranged between 92.7% and 97.1%. Regarding the pharmacokinetic parameters of tail intravenous injection of cucurbitacin, AUC (0-t) was (811.615 +/- 111.578) microg x h x L(-1), (t1/2) was (1.285 +/- 1.390) h, CL was (3.627 +/- 0.487) L x h x kg(-1), and V(d) was (6.721 +/- 7.429) L x kg(-1). In this study, researchers established a simple, accurate, sensitive and highly specific method for determining the blood concentration of cucurbitacin, and reported the in vivo pharmacokinetic characteristics of cucurbitacin in rats for the first time.

Comparison of preparing two polylactide nanoparticles loaded lipophilic anti-cancer herb drug by nanoprecipitation method / 中国中药杂志

This paper introduced an experimental study of polylacticacid (PLA) nanoparticles of lipophilic anti-cancer herb drug using a precipitation method. Cucurbitacins (Cu) and Curcuminoids (Cur) were selected to be model drugs. They had similar solubility but their incorporation effects were significantly different: the average drug entrapment ratio, the average drug loading and the average drug recovery were 38.53%, 2.21% and 27.02% respectively; while those of Cur-PLA-NP were 94.36%, 14.35% and 91.23% respectively. To analyse the reason, drug incorporation process was investigated. By measuring solvent evaporation rate, ratio of drug PLA precipitates, drug distribution in system and entrapping ratio at different time of preparation, we found the difference of precipitation velocity of drug was the main reason. We also concluded that not all lipophilic drug can be well entrapped into PLA nanoparticle by nanoprecipitation method. The drug incorporation depended on the interations among drug, PLA and organic solvents, in addition to the solubility of the drug.

The preparation of the polylacticacid nanoparticles of cucurbitacin and their drug loading / 中国中药杂志

This paper introduced an experimental study of the preparation of polylacticacid (PLA) nanoparticles of cucurbitacin (CuC) using a precipitation method. The residual acetone, ratio of CuC PLA precipitates, and the relationships between the ratios of two precipitates and drug incorporation rates were measured. It appeared that the nanoparticles with 60% of PLA incorporated with 5.5% of CuC were formed when acetone was injected into the aqueous phase. As the acetone gradually evaporated, drug incorporation/encapsulation continued, with most of CuC (about 70%) formed new crystalline cores and suspended in the form of microcrystals in the medium, resulting a suspension containing both nanoparticles and microcrystals. We also concluded that this system may not necessarily be suitable for all lipophilic drugs to be prepared to PLA nanoparticles with good incorporation rate. The drug incorporation depended on the interactions among drug, PLA, and organic solvents, in addition to the solubility of the drug.

The study of cucurbitacin BE polylactic acid nanoparticles delivering cucurbitacin BE to metastasized cervical lymph nodes in mice with oral cancer / 华西口腔医学杂志

<p><b>OBJECTIVE</b>The aim of this study was to investigate the delivery of Cucurbitacin BE to cervical lymph nodes by peri-cancer submucosal injection of the average diameter 85 nm Cucurbitacin BE polylactic acid nanoparticles (CuBE-PLA-NP).</p><p><b>METHODS</b>Cervical lymph node metastasis model of mice oral cancer was established and CuBE-PLA-NP and CuBE were injected in peri-cancer submucosal of the mice respectively, the concentration in blood, heart, liver, spleen, lung, kidney and cervical lymph node were measured by high performance liquid chromatography at fifteen time points, Targeted cervical lymph nodes were evaluated by targeting index, selectivity index, targeting efficiency, relative targeting efficiency and ratio of maximum concentration.</p><p><b>RESULTS</b>(1) The CuBE concentration in the cervical lymph nodes after CuBE-PLA-NP injection was far higher than that after CuBE injection at every time point, the CuBE duration in the cervical lymph nodes in CuBE-PLA-NP group was far longer than that in CuBE group; (2) The five targeted values of the cervical lymph nodes in CuBE-PLA-NP group was far higher than that in CuBE group; (3) The CuBE concentration in blood, heart, liver, spleen, lung and kidney in CuBE-PLA-NP group was far lower than that in CuBE group.</p><p><b>CONCLUSION</b>The CuBE-PLA-NP can specifically deliver CuBE to the cervical lymph nodes by peri-cancer submucosal injection, increase CuBE concentration and duration in metastasized cervical lymph nodes, and decrease drug concentration of other organs.</p>

Clinical application of anticancer nanoparticles targeting metastasis foci of cervical lymph nodes in patients with oral carcinoma / 华西口腔医学杂志

<p><b>OBJECTIVE</b>The aim of this study was to investigate the target delivery of Cucurbitacin BE (CuBE) to cervical lymph nodes by peri-oral-cancer submucosal injection of the average diameter 85 nm Cucurbitacin BE poly-lactic acid nanoparticles (CuBE-PLA-NP) and evaluate its clinical therapy efficacy.</p><p><b>METHODS</b>CuBE and CuBE-PLA-NP were respectively injected into peri-oral-cancer submucosa at 2, 12, 24, 48, 72, 96, 120, 144, 168 and 192 hours before operation in 26 patients with oral cancer. The concentrations of CuBE in cervical lymph nodes and blood were measured by high performance liquid chromatography (HPLC) at every time point. Cancer cell degeneration and necrosis in metastasis foci of cervical lymph nodes were observed using light microscope and electron microscope.</p><p><b>RESULTS</b>(1) The CuBE concentrations in cervical lymph nodes after CuBE-PLA-NP injection were far higher than those after CuBE injection at every time point, the duration of CuBE existing in the cervical lymph nodes in CuBE-PLA-NP group was far longer than those in CuBE group, the area under the CuBE concentrations-time curve of the cervical lymph nodes in CuBE-PLA-NP group was 43.67 times as many as that in CuBE group; (2) The CuBE ratio of maximum concentrations in the cervical lymph nodes in CuBE-PLA-NP group was 106.46 times as high as that in CuBE group; (3) The CuBE concentrations in the blood in CuBE-PLA-NP group was far lower than that in CuBE group; (4) Cancer cell necrosis and degeneration in the metastasis foci of cervical lymph nodes were found in CuBE-PLA-NP group, necrosis and degeneration were not found in CuBE group.</p><p><b>CONCLUSION</b>The peri-oral-cancer submucosa injection of the average diameter of 85 nm CuBE-PLA-NP can specifically delivery CuBE to the cervical lymph nodes, enhance treatment efficiency, and reduce general toxicity.</p>