A validated high-performance liquid chromatography method for detecting geniposide, ellagic acid, piperine, costunolide and dehydrocostus lactone in Liuwei Muxiang capsules.

In this study, a sensitive high-performance liquid chromatography detector was established and validated for the simultaneous determination of geniposide, ellagic acid, piperine, costunolide and dehydrocostuslactone in Liuwei Muxiang Capsules. The analysis was achieved on CHANIN 100-5-C18-H column (5µm, 250 mm×4.6 mm) with the temperature of 30oC. Gradient elution was applied using 0.1% phosphoric acid solution-methanol-acetonitrile (50:50) as mobile phase at the flow rate of 1.0 mL/min. The determination was performed at the wavelength of 225 nm (detecting geniposide), 254 nm (detecting ellagic acid), 343 nm (detecting piperine) and 225 nm (detecting costunolide and dehydrocostuslactone) along with the sample volume of 10µL. The linear ranges of geniposide, ellagic acid, piperine, costunolide and dehydrocostuslactone demonstrated good linear relationships within their respective determination ranges. The average recoveries were 100.04%, 99.86%, 99.79%, 100.17% and 100.41%, respectively. RSD% was 1.3%, 1.2%, 1.2%, 1.2%, 1.5%, respectively. The developed method was proved to be simple, accurate and sensitive, which can provide a quantitative analysis method for the content determination of geniposide, ellagic acid, piperine, costunolide and dehydrocostuslactone in Liuwei Muxiang capsules.

Identification of the metabolites of methylophiopogonanone A by ultra-high-performance liquid chromatography combined with high-resolution mass spectrometry.

RATIONALE: Methylophiopogonanone A (MOA) is a naturally occurring homoisoflavonoid from the Chinese herb Ophiopogon japonicus, which has been demonstrated to attenuate myocardial apoptosis. However, the metabolism of MOA remains unknown. The goal of the present work was to investigate the in vitro metabolism of MOA using liver microsomes and hepatocytes. METHODS: The metabolites were generated by incubating MOA with rat, monkey and human liver microsomes or hepatocytes. The resulting samples were analyzed by using a quadrupole-orbitrap high-resolution mass spectrometer. The metabolites were identified through the measurements of the exact mass, elemental composition and product ions. RESULTS: A total of 15 metabolites were detected and identified. Among these metabolites, M7 (demethylenation) was the most abundant metabolite in liver microsomes, while M6 (hydroxylation) was the predominant metabolite in hepatocytes, and glucuronidation metabolites (M9 and M10) were also the main metabolites in hepatocytes. The metabolic pathways of MOA included hydroxylation, demethylenation, glucuronidation, methylation, sulfation and glutathione conjugation. CONCLUSIONS: This study for the first time provides valuable data on the metabolites of MOA, which will be of great importance for a better understanding of its disposition and to predict human pharmacokinetics.

Development and validation of a rapid high-performance thin-layer chromatographic method for quantification of gallic acid, cinnamic acid, piperine, eugenol, and glycyrrhizin in Divya-Swasari-Vati, an ayurvedic medicine for respiratory ailments.

Divya-Swasari-Vati is a calcium containing polyherbal ayurvedic medicine prescribed for the lung-related ailments observed in the current pandemic of Severe Acute Respiratory Syndrome Coronavirus 2 infections. The formulation is a unique quintessential blend of nine herbs cited in Ayurvedic texts for chronic cough and lung infection. Analytical standardization of herbal medicines is the pressing need of the hour to ascertain the quality compliance. This persuaded us to develop a simple, rapid, and selective high-performance thin-layer chromatographic method for Divya-Swasari-Vati quality standardization. The developed method was validated for the quantification of marker components, gallic acid, cinnamic acid, piperine, eugenol and glycyrrhizin, against reference standards in five different batches of Divya-Swasari-Vati. The analytes were identified by visualization at 254 nm, and by matching their retention factor with authentic standards. The developed method was validated as per the guidelines recommended by the International Council for Harmonization for parameters like, linearity, limit of detection, limit of quantification, accuracy, and precision. Therefore, the developed novel high-performance thin-layer chromatographic process could be employed for rapid standardization of Divya-Swasari-Vati and other related herbal formulation, which would aid in quality manufacturing and product development.

The inhibitory effects of sesamol and sesamolin on the glycidyl esters formation during deodorization of vegetables oils.

BACKGROUND: Glycidyl esters (GEs) have attracted worldwide attention for their potential harm to human health. The GEs in edible oils mainly form during the deodorization of the oil refining processes. We used sesamol and sesamolin to inhibit the formation of GEs in model corn oil (MCO), model palm oil (MPO) and model rice bran oil (MRO) during a deodorization process. RESULTS: The results showed that, in the three model oils, the total GE content was in the following order from highest to lowest: MRO (1437.98 µg kg-1 ) > MPO (388.64 µg kg-1 ) > MCO (314.81 µg kg-1 ). The inhibitory effect of the three antioxidants on the formation of GEs in the MCO was in the following order from strongest to weakest: tert-butylhydroquinone (TBHQ) > sesamol > sesamolin. CONCLUSION: When the mass percentage of sesamol was 0.05%, its inhibition percentage on GEs was close to the inhibition percentage of 0.02% added TBHQ. The present study provides a foundation for understanding how to inhibit the formation of GEs in oils by adding sesamol during the deodorization process.

Identification of the metabolites of piperine via hepatocyte incubation and liquid chromatography combined with diode-array detection and high-resolution mass spectrometry.

RATIONALE: Piperine, an alkaloid isolated from Piper nigrum L., has been demonstrated to have many pharmacological effects and several health benefits. The aim of this work was to study the metabolic profiles of piperine in mouse, rat, dog and human hepatocytes. METHODS: The biotransformation was carried out by incubating piperine with hepatocytes at 37°C. After incubation for 2 h, the samples were pretreated and analyzed using liquid chromatography combined with diode-array detection and high-resolution mass spectrometry (LC/DAD-HRMS). The structures of the metabolites were assigned through a comparison of their accurate masses and product ions with those of the parent compound. RESULTS: A total of 20 metabolites were detected, and the structures were proposed. Piperine was metabolized through the following pathways: (a) oxidation to form a catechol derivative, which further underwent methylation, glucuronidation, glutathione (GSH) conjugation, and hydroxylation followed by opening of the piperidine ring; (b) hydroxylation to form a carbinolamine intermediate followed by opening of the piperidine ring and the formation of alcohol and acid derivatives; and (c) hydroxylation to form stable hydroxylated metabolites. In mouse, the formation of the catechol derivative (M12) and hydroxylation (M11) were the major metabolic pathways; in rat, the formation of the catechol derivative (M12) and glucuronidation (M9) were the main pathways; and in dog and human, the formation of the catechol derivative (M12) was the predominant pathway. No human-specific metabolite was observed. CONCLUSIONS: This study provided some new information on the metabolic profiles of piperine, which should be of great importance in the study of the pharmacology and toxicity of this compound.

Switchable-hydrophilicity solvent liquid-liquid microextraction versus dispersive liquid-liquid microextraction prior to HPLC-UV for the determination and isolation of piperine from Piper nigrum L.

Switchable-hydrophilicity solvent liquid-liquid microextraction and dispersive liquid-liquid microextraction were compared for the extraction of piperine from Piper nigrum L. prior to its analysis by using high-performance liquid chromatography with UV detection. Under optimum conditions, limits of detection and quantitation were found as 0.2-0.6 and 0.7-2.0 µg/mg with the two methods, respectively. Calibration graphs showed good linearity with coefficients of determination (R2 ) higher than 0.9962 and percentage relative standard deviations lower than 6.8%. Both methods were efficiently used for the extraction of piperine from black and white pepper samples from different origins and percentage relative recoveries ranged between 90.0 and 106.0%. The results showed that switchable-hydrophilicity solvent liquid-liquid microextraction is a better alternative to dispersive liquid-liquid microextraction for the routine analysis of piperine in food samples. A novel scaled-up dispersive liquid-liquid microextraction method was also proposed for the isolation of piperine providing a yield of 102.9 ± 4.9% and purity higher than 98.0% as revealed by NMR spectroscopy.

In vitro isolation of small-molecule-binding aptamers with intrinsic dye-displacement functionality.

Aptamer-based sensors offer a powerful tool for molecular detection, but the practical implementation of these biosensors is hindered by costly and laborious sequence engineering and chemical modification procedures. We report a simple strategy for directly isolating signal-reporting aptamers in vitro through systematic evolution of ligands by exponential enrichment (SELEX) that transduce binding events into a detectable change of absorbance via target-induced displacement of a small-molecule dye. We first demonstrate that diethylthiatricarbocyanine (Cy7) can stack into DNA three-way junctions (TWJs) in a sequence-independent fashion, greatly altering the dye's absorbance spectrum. We then design a TWJ-containing structured library and isolate an aptamer against 3,4-methylenedioxypyrovalerone (MDPV), a synthetic cathinone that is an emerging drug of abuse. This aptamer intrinsically binds Cy7 within its TWJ domain, but MDPV efficiently displaces the dye, resulting in a change in absorbance within seconds. This assay is label-free, and detects nanomolar concentrations of MDPV. It also recognizes other synthetic cathinones, offering the potential to detect newly-emerging designer drugs, but does not detect structurally-similar non-cathinone compounds or common cutting agents. Moreover, we demonstrate that the Cy7-displacement colorimetric assay is more sensitive than a conventional strand-displacement fluorescence assay. We believe our strategy offers an effective generalized approach for the development of sensitive dye-displacement colorimetric assays for other small-molecule targets.

Selective in vivo molecular and cellular biocompatibility of black peppercorns by piperine-protein intrinsic atomic interaction with elicited oxidative stress and apoptosis in zebrafish eleuthero embryos.

Day to day consumption of black pepper raise concern about the detailed information about their medicinal, pharmaceutical values and knowledge about the biocompatibility with respect to ecosystem. This study investigates the in vivo selective molecular biocompatibility of its seed cover (SC) and seed core (SP) powder extract using embryonic zebrafish model. Gas chromatography mass spectrometry (GCMS) analysis of the extract prepared by grinding showed presence of different components with "piperine" as principle component. Biocompatibility analysis showed dose and time dependent selective effect of SC and SP with LC50 of 30.4 µg/ml and 35.6 µg/ml, respectively on survivability, hatching and heartbeat rate in embryonic zebrafish. Mechanistic investigation elucidated it as effect of accumulation and internalization of black pepper leading to their influence on structure and function of cellular proteins hatching enzyme (he1a), superoxide dismutase (sod1) and tumor protein (tp53) responsible for delayed hatching, oxidative stress induction and apoptosis. The study provided insight to selective biocompatibility of black pepper expedient to produce higher quality spices with respect to pharmaceutical, clinical and environmental aspects.

Label-Free, Visual Detection of Small Molecules Using Highly Target-Responsive Multimodule Split Aptamer Constructs.

Colorimetric aptamer-based sensors offer a simple means of on-site or point-of-care analyte detection. However, these sensors are largely incapable of achieving naked-eye detection, because of the poor performance of the target-recognition and signal-reporting elements employed. To address this problem, we report a generalizable strategy for engineering novel multimodule split DNA constructs termed "CBSAzymes" that utilize a cooperative binding split aptamer (CBSA) as a highly target-responsive bioreceptor and a new, highly active split DNAzyme as an efficient signal reporter. CBSAzymes consist of two fragments that remain separate in the absence of target, but effectively assemble in the presence of the target to form a complex that catalyzes the oxidation of 2,2'-azino-bis(3-ethylbenzthiazoline)-6-sulfonic acid, developing a dark green color within 5 min. Such assay enables rapid, sensitive, and visual detection of small molecules, which has not been achieved with any previously reported split-aptamer-DNAzyme conjugates. In an initial demonstration, we generate a cocaine-binding CBSAzyme that enables naked-eye detection of cocaine at concentrations as low as 10 µM. Notably, CBSAzyme engineering is straightforward and generalizable. We demonstrate this by developing a methylenedioxypyrovalerone (MDPV)-binding CBSAzyme for visual detection of MDPV and 10 other synthetic cathinones at low micromolar concentrations, even in biological samples. Given that CBSAzyme-based assays are simple, label-free, rapid, robust, and instrument-free, we believe that such assays should be readily applicable for on-site visual detection of various important small molecules such as illicit drugs, medical biomarkers, and toxins in various sample matrices.

Enantioselective determination of cathinones in urine by high pressure in-line SPE-CE.

This work presents a strategy based on the in-line coupling of SPE and CE for the chiral determination of cathinones (R,S-mephedrone, R,S-4-methylephedrine, and R,S- methylenedioxypyrovalerone) in urine samples, using a sample pretreatment based on liquid-liquid extraction. The chiral separation of the compounds is achieved by adding a mixture of 8 mM 2-hydroxypropil ß-CD and 5 mM ß-CD to the BGE, which consists of 70 mM of monosodium phosphate aqueous solution at pH 2.5. Oasis HLB was the selected sorbent for the in-line SPE device, and to reduce analysis time and LODs, several parameters affecting the in-line SPE system were evaluated, such as pressure and time of sample injection and dimensions of the SPE device. The highest preconcentration factors were achieved by using 3 bar of injection pressure for 20 min with an in-line SPE device of 2 mm length and 150 µm of i.d. The developed method was applied to determine the presence of the compounds in spiked urine samples. The LODs obtained were between 3 and 8 ng/mL, and these levels were below the usual concentrations at which these drugs are present in urine from cathinone abusers. Thus, the optimized method has the potential to be applied for toxicological and forensic purposes.

Synthesis of the chiral selector heptakis(6-O-methyl)-ß-cyclodextrin by phase-transfer catalysis and hydrazine-mediated transfer-hydrogenation.

The exhaustive primary-side alkylation of cyclodextrins has never been achieved directly. The undesired and simultaneous derivatization of the secondary hydroxyl moieties generates intricate isomeric mixtures that are challenging to purify, analyse and characterize. The aim of this study was to develop a chromatography-free and up-scalable strategy towards the preparation of per-6-O-methylated cyclodextrin and to test the compound as potential chiral selector. The target molecule was prepared according to a five-step synthesis by using methyltriphenylphosphonium bromide as catalyst under heterogeneous conditions. The removal of benzyl moieties, used as temporary secondary-side protecting groups, was attained by applying hydrazine-carbonate in the presence of Pd/C. All the intermediates were obtained in high yields, thoroughly characterized and their purity was assessed by ad-hoc developed HPLC methods. The per-6-O-methylated ß-cyclodextrin showed promising chiral recognition ability as background electrolyte additive in cyclodextrin-modified capillary electrophoresis using the recreational drug methylene-dioxypyrovalerone as model compound. Additionally, a model for the inclusion geometry between the single isomer host and the selected drug was developed based on the extensive 2D NMR analysis. The versatility of the proposed synthetic strategy opens the way to the industrial production of homogeneously primary-alkylated cyclodextrins and to their wide application in chiral separation of various drugs.

Simultaneous determination of six components in commercial Roukou Wuwei pills using ultra-high-performance liquid chromatography with diode-array detector.

An efficient ultra-performance liquid chromatography with diode-array detector method was established for simultaneous determination of six active components in Roukou Wuwei pills, namely gallic acid, piperine, costundide, dehydrocostus lactone, isoalantolactone and alantolactone. Chromatographic separation of six components was successfully achieved on an Waters BEH C18 column (50 × 2.1 mm, 1.7 µm) with a mobile phase composed of acetonitrile and water using a gradient elution. Gallic acid and piperine were detected at 270 nm and 343 nm, respectively; while costundide, dehydrocostus lactone, isoalantolactone and alantolactone were simultaneously measured at 225 nm. All six calibration curves showed good linearity (R2 ≥ 0.9994) between the peak area of each component and corresponding concentration. Relative standard deviations for inter- and intra-day precisions were <0.45 and 0.77%, respectively. The mean recovery rates ranged from 96.72 to 102.2% with relative standard deviations <2.07%. The developed method was validated in terms of linearity, precision and accuracy and then successfully applied for the quality control of commercial Roukou Wuwei samples.

Simultaneous determination of N-ethylpentylone, dopamine, 5-hydroxytryptamine and their metabolites in rat brain microdialysis by liquid chromatography tandem mass spectrometry.

N-Ethylpentylone (NEP) is a popular synthetic cathinone abused worldwide. To obtain more information about its pharmacokinetics and pharmacodynamics, a rapid, simple and sensitive liquid chromatography-tandem mass spectrometry method was developed for the determination of NEP, two important neurotransmitters, dopamine and serotonin, and their metabolites, including 3,4-dihydroxyphenylacetic acid, 3-methoxytyramine and 5-hydroxyindole-3-acetic acid, in rat brain microdialysate. The analytes were separated on a Phnomenex Polar C18 column, with a mobile phase of 0.1% formic acid in water (A) and 0.1% formic acid in acetonitrile (B) under gradient elution to shorten the total chromatographic run time. A triple quadruple mass spectrometer coupled with an electrospray ionization source in both positive and negative ion mode was used to detect the analytes. This method showed excellent accuracy (87.4-113.5%) and precision (relative standard deviation <15%) at three quality control levels. The limits of detection were 0.2 ng/mL for NEP and 0.2-50 nm for the others and good linearity was obtained. This study pioneered a method to integrate exogenous drugs and endogenous neurotransmitters as the drugs act on the same determination system, which means that this innovation can provide support for further study of the addictive effects of NEP or other synthetic cathinones on extracellular levels of dopamine and 5-hydroxytryptamine.

Validation of Cell-Based Assay for Quantification of Sesamol Uptake and Its Application for Measuring Target Exposure.

The intracellular drug concentration is needed for determined target exposure at the site of action regarding its pharmacological action and adverse effects. Sesamol is an antiproliferative molecule from Sesamum indicum with promising health benefits. We present a method for measuring the intracellular sesamol content using reverse-phase HPLC with a UV diode array in melanoma cells. Sesamol was completely resolved by isocratic elution (4.152 ± 0.008 min) with methanol/water (70%, v/v) through a 30 °C, 5-µm C-18 column and detection at 297 nm. The present assay offers high sensitivity, fast elution, and an accurate and linear nominal concentration range of 10-1000 ng/mL (R2 = 0.9972). The % accuracy of the sesamol quality control sample was -3.36% to 1.50% (bias) with a 0.84% to 5.28% relative standard deviation (RSD), representing high repeatability and high reproducibility. The % recovery was 94.80% to 99.29%, which determined that there was no loss of sesamol content during the sample preparation. The validated method was applied to monitor intracellular sesamol concentration after treatment from 5 min to 24 h. The remaining intracellular sesamol content was correlated with its antiproliferative effect (R2 = 0.9483). In conclusion, this assay demonstrated low manipulation, quick elution, and high sensitivity, precision, accuracy, and recovery, and it was successfully applied to the quantification of sesamol in target cells.

[Quantitative Analysis of Piperine and the Derivatives in Long Pepper Extract by HPLC Using Relative Molar Sensitivity].

A novel method was developed for quantification of five major piperine derivatives (piperanine, piperine, chavicine, isopiperine, and isochavicine) in a hot water extract of long pepper fruit (LPE) using the relative molar sensitivity (RMS) based on the combination of HPLC/UV and 1H- quantitative NMR (1H-qNMR). The RMSs of piperanine, chavicine, isopiperine, and isochavicine to piperine of which the absolute purity was determined by 1H-qNMR were calculated to be 0.3693, 1.138, 0.9164, and 1.277, respectively. The total amount of piperine derivatives in LPE was quantified by both 1H-qNMR and HPLC/UV based on the RMS using piperine as a single-reference material (RMS method). The relative difference in quantitation values of 1H-qNMR and calibration curve method from the RMS method was 2.01% or less. The relative difference of the total cis-trans piperine isomers content between before and after photoirradiation in piperine solution was quantified to be 2.84% by the RMS method. In addition, the interlaboratory difference of the RMS method was confirmed in the range of 0.600 to 4.00 µg/g when analysis was performed on piperine derivatives in LPE containing tablets, while the total amount of piperine derivatives in the tablets was quantified at 606 µg/g. Our proposed method is a reliable tool for determining the contents of piperine and the derivatives in LPE and processed foods containing LPE.

Glycyrrhiza glabra HPLC fractions: identification of Aldehydo Isoophiopogonone and Liquirtigenin having activity against multidrug resistant bacteria.

BACKGROUND: Medicinal plants have been founded as traditional herbal medicine worldwide. Most of the plant's therapeutic properties are due to the presence of secondary metabolites such as alkaloids, glycosides, tannins and volatile oil. METHODS: The present investigation analyzed the High-Pressure Liquid Chromatography (HPLC) fractions of Glycyrrhiza glabra (Aqueous, Chloroform, Ethanol and Hexane) against multidrug resistant human bacterial pathogens (Escherichia coli, Acinetobacter baumannii, Staphylococcus aureus and Pseudomonas aeruginosa). All the fractions showed antibacterial activity, were subjected to LC MS/MS analysis for identification of bioactive compounds. RESULTS: Among total HPLC fractions of G. glabra (n = 20), three HPLC fractions showed potential activity against multidrug resistant (MDR) bacterial isolates. Fraction 1 (F1) of aqueous extracts, showed activity against A. baumannii (15 ± 0.5 mm). F4 from hexane extract of G. glabra showed activity against S. aureus (10 ± 0.2 mm). However, F2 from ethanol extract exhibited activity against S. aureus (10 ± 0.3 mm). These active fractions were further processed by LC MS/MS analysis for the identification of compounds. Ellagic acid was identified in the F1 of aqueous extract while 6-aldehydo-isoophiopogonone was present in F4 of hexane extract. Similarly, Liquirtigenin was identified in F2 of ethanol. CONCLUSIONS: Glycyrrhiza glabra extracts HPLC fractions showed anti-MDR activity. Three bioactive compounds were identified in the study. 6-aldehydo-isoophiopogonone and Liquirtigenin were for the first time reported in G. glabra. Further characterization of the identified compounds will be helpful for possible therapeutic uses against infectious diseases caused by multidrug resistant bacteria.

Characterization of piperine metabolites in rats by ultra-high-performance liquid chromatography with electrospray ionization quadruple time-of-flight tandem mass spectrometry.

RATIONALE: Piperine is a major constituent of Piper nigrum L. and is a naturally bioactive alkaloid. Structural changes in piperine have been shown to result in different biological effects. The present study aims to investigate piperine metabolites in rat plasma, bile, urine, and feces after oral administration. METHODS: The metabolic pathway of piperine in vivo was investigated using ultra-high-performance liquid chromatography (UHLPC) combined with electrospray ionization quadruple time-of-flight tandem mass spectrometry (QTOF-MS). Piperine metabolites were found and identified by fragmentation patterns and accurate mass measurements. RESULTS: The 12 metabolites detected and identified were divided into three groups: methylenedioxycyclic ring-opening metabolites (M01-M08), methylenedioxycyclic ring-oxidizing metabolites (M09-M11), and piperidine ring-cleavage metabolites (M12). Seven piperine metabolites, including M02, M03, M04, M05, M09, M10 and M11, were reported for the first time in the literature. CONCLUSIONS: Results showed that the principal metabolism pathways of piperine in rat were reduction and demethylation after ring-opening, and that UHPLC/QTOF-MS can serve as an important analytical platform to gather the piperine metabolism profile. Copyright © 2017 John Wiley & Sons, Ltd.

Determination of a natural DNMT1 inhibitor, peperomin E, in rat plasma by UFLC-MS/MS and method application in a pharmacokinetic study.

Peperomin E (PepE), a naturally occurring secolignan isolated from Peperomia dindygulensis, has drawn much attention recently owing to its anticancer and DNA methyltransferase 1 (DNMT1) inhibitory activity. Here, a simple and sensitive ultra-fast liquid chromatography-tandem mass spectrometry method was developed and validated for the determination of PepE in rat plasma for the first time. Samples were prepared by simple protein precipitation. Separation was performed on an XBridge™ C18 column using a mobile phase of acetonitrile and 0.1% (v/v) aqueous formic acid. PepE and the internal standard arctigenin were detected in a positive-ion mode using multiple reaction monitoring of the transitions at m/z 413.2 → 261.0 and 373.2 → 137.2, respectively. The calibration curve for PepE was linear over the range of concentrations of 1.46-6000 ng/mL, with a lower limit of quantitation of 1.46 ng/mL. Both intra- and interday precisions were within 11.05%, and the accuracy ranged from -11.5 to 5.51%. The extraction recovery and matrix effect were within acceptable limits. Stability tests showed that PepE remained stable throughout the analytical procedure. The validated method was then used to analyze the pharmacokinetics of PepE administered to rats orally (12.5 and 25 mg/kg) or intravenously (6.25 and 12.5 mg/kg).

Identification of anti-cancer chemical compounds using Xenopus embryos.

Cancer tissues have biological characteristics similar to those observed in embryos during development. Many types of cancer cells acquire pro-invasive ability through epithelial-mesenchymal transition (EMT). Similar processes (gastrulation and migration of cranial neural crest cells [CNCC]) are observed in the early stages of embryonic development in Xenopus during which cells that originate from epithelial sheets through EMT migrate to their final destinations. The present study examined Xenopus embryonic tissues to identify anti-cancer compounds that prevent cancer invasion. From the initial test of known anti-cancer drugs, AMD3100 (an inhibitor of CXCR4) and paclitaxel (a cytoskeletal drug targeting microtubules) effectively prevented migration during gastrulation or CNCC development. Blind-screening of 100 synthesized chemical compounds was performed, and nine candidates that inhibited migration of these embryonic tissues without embryonic lethality were selected. Of these, C-157 (an analog of podophyllotoxin) and D-572 (which is an indole alkaroid) prevented cancer cell invasion through disruption of interphase microtubules. In addition, these compounds affected progression of mitotic phase and induced apoptosis of SAS oral cancer cells. SAS tumors were reduced in size after intratumoral injection of C-157, and peritoneal dissemination of melanoma cells and intracranial invasion of glioma cells were inhibited by C-157 and D-572. When the other analogues of these chemicals were compared, those with subtle effect on embryos were not tumor suppressive. These results suggest that a novel chemical-screening approach based on Xenopus embryos is an effective method for isolating anti-cancer drugs and, in particular, targeting cancer cell invasion and proliferation.

Determination of 3,4-methylenedioxypyrovalerone (MDPV) in oral and nasal fluids by ion mobility spectrometry.

A fast and sensitive methodology has been developed for the evaluation of the 3,4-methylenedioxypyrovalerone (MDPV) consumed. Based on ion mobility spectrometry (IMS), MDPV was directly determined in nasal fluids with a limit of detection (LOD) in the order of 22 ng mL(-1), which corresponds to an absolute amount of 33 ng of MDPV per swab. MDPV was also determined after liquid-liquid microextraction (LLME) in oral fluids to avoid matrix effects, obtaining a LOD value of 4.4 ng mL(-1) in oral fluid samples. The IMS spectrum for MDPV exhibited a peak with K0 = 1.210 ± 0.005 cm(2)V(-1) s(-1) at a drift time of 14.62 ms, the total analysis time being 4.5 min per oral fluid and 1.5 min per nasal fluid sample. Samples must be analyzed within 24 h following collection and dissolution in 2-propanol, based on the complementary stability studies.