Aqueous extract of Sanguisorba officinalis blocks the Wnt/ß-catenin signaling pathway in colorectal cancer cells.

Sanguisorba officinalis (the Chinese name is DiYu, DY) exerts significant anti-proliferative activities against colorectal cancer (CRC) cells. Since most of CRC result from the aberrant activation of the Wnt/ß-catenin signaling pathway, inhibitors of the Wnt pathway are considered as promising anti-CRC agents. This study aimed to investigate whether DY could be a potential herbal Wnt inhibitor, and the bioactive constituents and underlying molecular mechanisms for DY's inhibiting activities would be studied as well. Accordingly, the inhibitory activities of DY and its main components against the Wnt pathway were assessed using the single-luciferase reporter assay based on HEK293 cells. Additionally, the levels of key Wnt-related genes or proteins were measured to verify the inhibitory effects on the Wnt pathway of CRC cells. Finally, the underlying mechanisms accounting for the efficacy of candidate drugs were explored by the transcriptomic study. Results show that DY and its tannins (RZ), and saponins (ZG) significantly inhibited the Wnt pathway of HEK293 cells activated by wnt3a. However, their respective constituents were not effective as expected. Additionally, DY and RZ prominently down-regulated the levels of ß-catenin and Wnt-targeted genes including Axin2, c-Myc or CyclinD1 of three CRC cells. Transcriptomic profiling study suggests that the down-regulation of the mRNA levels of Wnt-related genes such as LPAR6 may be associated with the inhibitory effects of DY and RZ on the Wnt pathway of HT29 cells. Therefore, our studies first uncovered the blocking activity of DY on the Wnt pathway, providing evidence for the rationale of developing Wnt inhibitors from DY as anti-CRC agents.

Sanguisorba officinalis L synergistically enhanced 5-fluorouracil cytotoxicity in colorectal cancer cells by promoting a reactive oxygen species-mediated, mitochondria-caspase-dependent apoptotic pathway.

Sanguisorba officinalis L. radix is a widely used herb called DiYu (DY) in China and has an extensive range of bioactivities, including anti-cancer, anti-inflammatory, and anti-oxidative activities. However, there is little evidence to support its anti-cancer effects against colorectal cancer (CRC). The first-line chemotherapeutic agent 5-fluorouracil (5-FU) is used to treat CRC, but its efficiency is hampered by acquired drug resistance. This study found that a water extract of DY exerted anti-proliferative effects against two CRC cell lines (HCT-116 and RKO), and it sensitized CRC cells to 5-FU therapy by activating a reactive oxygen species (ROS)-mediated, mitochondria-caspase-dependent apoptotic pathway. Co-treatment of DY and 5-FU significantly elevated ROS levels, up-regulated Bax/Bcl-2 ratio and triggered mitochondrial dysfunction, followed by a release of cytochrome c and up-regulation of proteins such as cleaved-caspase-9/3 and cleaved-PARP. Additionally, the induction of autophagy may be involved in mediating synergism of DY in HCT-116 cells. Gallic acid (GA), catechinic acid (CA) and ellagic acid (EA) were identified as the potential chief constituents responsible for the synergistic effects of DY. In conclusion, co-treatment of DY, specifically GA, CA and EA, with 5-FU may be a potential alternative therapeutic strategy for CRC by enhancing an intrinsic apoptotic pathway.

Analysis of arecoline in Semen Arecae decoction pieces by microchip capillary electrophoresis with contactless conductivity detection.

A new method for the determination of arecoline in Semen Arecae decoction pieces by microchip capillary electrophoresis with contactless conductivity detection (MCE-CCD) was proposed. The effects of various electrophoretic operating parameters on the analysis of arecoline were studied. Under the optimal conditions, arecoline was rapidly separated and detected in 1 min with good linearity over the concentration range of 20-1500 µM (r2=0.9991) and the detection limit of 5 µM (S/N=3). The method was used for the analysis of arecoline satisfactorily with a recovery of 96.8-104%.

An automated fluid-transport device for a microfluidic system.

An automated fluid-transport device for a chip-based capillary electrophoresis system has been developed. The device mainly consists of six peristaltic micropumps, two vacuum micropumps, microvalves, multi-way joints, titanium tubes, and a macro-to-micro connector. Various solutions used for the cleaning and activation of chip channels, and electrophoresis separation, are allowed to automatically transport to chip reservoirs by the electric control module. The performance of the whole system was characterized by the analysis of fluorescein sodium using chip electrophoresis with LED-induced fluorescence detection. The peak-height variation (RSD) was 3.8% in six cycles of analyses. Additionally, compared with conventional manual operation, the developed device can spare 60% time for chip pretreatment. This microdevice offers high-efficiency pretreatment for microchips, thereby resulting in a remarkable improvement of analytical capacity for batch samples.

A facile light-emitting-diode induced fluorescence detector coupled to an integrated microfluidic device for microchip electrophoresis.

In this paper, a compact and inexpensive light emitting diode induced fluorescence (LED-IF) detector with simplified optical configuration was developed and assembled in an integrated microfluidic device for microscale electrophoresis. The facile detector mainly consisted of an LED, a focusing pinhole, an emission filter and a photodiode, and was encapsulated in the upper layer of an aluminum alloy device with two layers. At the bottom layer, integrated circuit (IC) was assembled to manipulate the voltage for sample injection and separation, LED emission and signal amplifying. A high-power LED with fan-shaped heat sink was used as excitation source. The excitation light was focused by a 1.1mm diameter pinhole fabricated in a thin piece of silver foil, and the obtained sensitivity was about 3 times as high as that using electrode plate. Other important parameters including LED driven current, fluorescence collection angle and detection distance have also been investigated. Under optimal conditions, considerable high-response of 0.09 fmol and 0.18 fmol mass detection limits at 0.37 nL injection volume for sodium fluorescein (SF) and FITC was achieved, respectively. This device has been successfully employed to separate penicillamine (PA) enantiomers. Due to such significant features as low-cost, integration, miniaturization, and ease of commercialization, the presented microfluidic device may hold great promise for clinical diagnostics and bioanalytical applications.

[Determination of matrine in matrine injection by microfluidic chip with contactless conductivity detection].

OBJECTIVE: To establish a new method for the determination of matrine in matrine injection by microfluidic chip with contactless conductivity detection. METHODS: The electrophoretic parameters, such as the variety and concentration of buffer solution and additive, separation voltage and injection time, etc. were researched. RESULTS: In the optimal conditions, using 2 mmol/L HAc + 2 mmol/L NaAc (pH 4. 5) as buffer solution, with 0.20 mmol/L SDS as addition at the separation voltage of 2.00 kV and 10s injection, matrine was separated and detected within 2 min. The linear dependence of the concentration of matrine ranged from 10 to 300 microg/mL (r2 = 0.9992), with the detection limit of 1.0 microg/mL (S/N = 3), the RSD of 1.9% and the recoveries from 98.7% to 101%. CONCLUSION: The method is simple, rapid and well reproducible, and it can be used in the quality control of the product.

[Advances on enzymes and enzyme inhibitors research based on microfluidic devices].

With the continuous development in microfluidic fabrication technology, microfluidic analysis has evolved from a concept to one of research frontiers in last twenty years. The research of enzymes and enzyme inhibitors based on microfluidic devices has also made great progress. Microfluidic technology improved greatly the analytical performance of the research of enzymes and enzyme inhibitors by reducing the consumption of reagents, decreasing the analysis time, and developing automation. This review focuses on the development and classification of enzymes and enzyme inhibitors research based on microfluidic devices.

Electromagnetic induction detector for capillary electrophoresis and its application in pharmaceutical analysis.

A new electromagnetic induction detector for capillary electrophoresis and its application are described. The detector is consisted of an inductor, a resistor, a high-frequency signal generator and a high-frequency millivoltmeter. The conditions affecting the response of the detector, including dimension of the magnetic ring, position of the capillary, number of coil turns, frequency, excitation voltage and value of the resistor were examined and optimized. The feasibility of the proposed detector was evaluated by detection of inorganic ions and separation of amino aids. Its quantification applicability was investigated by determination of aspirin and paracetamol in pharmaceutical preparation (Akafen powder). The primary factors affecting separation efficiency, which include variety of buffer, buffer concentration, injection time and injection height and separation voltage, were researched. Experimental results demonstrated that this new detector showed a well-defined correlation between sample concentrations and responses (r=0.997-0.999), with detection limits of 30 µmol L(-1) for aspirin and 10 µmol L(-1) for paracetamol, as well as good reproducibility and stability. Compared with currently available detection techniques, this new detector has several advantages, such as simple construction, no complicated elements, ease of assembly and operation, and potential for universal applications. It can be an alternative to the traditional methods in the quality control of the pharmaceutical preparations.

[Synthesis of 5-aryl-4-cyano-1H-1, 2, 3-triazoles and biological evaluation of their inhibitory action on tyrosine kinase].

5-Aryl-4-cyano-1H-1, 2, 3-triazoles bearing a variety of substituting groups on 5-phenyl were synthesized. Their structures were established by MS, IR and 1H NMR spectra. The crystal structures of compounds 3f and 3m were determined by X-ray diffraction analysis. The active H of the triazole was on 1-N from the crystal structures. The compounds, designed as HER2 tyrosine kinase inhibitors, were screened for bioactivity of growth-inhibition of breast cancer MDA-MB-453 cells. The lowest IC50 value of inhibiting HER2 tyrosine kinase phosphorylation in breast cancer cells is 6.6 micromol x L(-1). The inhibiting-growth of breast cancer cells was enhanced from electron-drawing groups joining 5-phenyl on the triazole.

Dual fluorescence/contactless conductivity detection for microfluidic chip.

A new dual detection system for microchip is reported. Both fluorescence detector (FD) and contactless conductivity detector (CCD) were combined together and integrated on a microfluidic chip. They shared a common detection position and responded simultaneously. A blue light-emitting diode was used as excitation source and a small planar photodiode was used to collect the emitted fluorescence in fluorescence detection, which made the device more compact and portable. The coupling of the fluorescence and contactless conductivity modes at the same position of a single separation channel enhanced the detection characterization of sample and offered simultaneous detection information of both fluorescent and charged specimen. The detection conditions of the system were optimized. K(+), Na(+), fluorescein sodium, fluorescein isothiocyanate (FITC) and FITC-labeled amino acids were used to evaluate the performance of the dual detection system. The limits of detection (LOD) of FD for fluorescein Na(+), FITC, FITC-labeled arginine (Arg), glycine (Gly) and phenylalanine (Phe) were 0.02micromolL(-1), 0.05micromolL(-1), 0.16micromolL(-1), 0.15micromolL(-1), 0.12micromolL(-1) respectively, and the limits of detection (LOD) of CCD achieved 0.58micromolL(-1) and 0.39micromolL(-1) for K(+) and Na(+) respectively.

Running buffers for determination of chromium(VI)/(III), cobalt(II) and zinc(II) in complex matrices by capillary electrophoresis with contactless conductivity detection.

Complex matrices and rather high acidity in environmental samples are often the impelling challenges for the used running buffers of capillary electrophoresis. Twelve binary acid-base buffers were evaluated for separation of Cr(VI)/Cr(III), Co(2+) and Zn(2+) in a sample containing various salts by capillary electrophoresis with contactless conductivity detector. The malic acid (MA) systems including MA-His (histidine), MA-Arg (arginine) and MA-Tris (tris(hydroxymethyl)aminomethane) were selected as the candidates with powerful separation efficiency and good response sensitivity. In the MA-Tris buffer, optimization were further carried out in terms of the pH value and the concentration of MA, and the optimal conditions were obtained as 6mM MA-Tris and 2mM 18-crown-6 at pH 3.5. Furthermore, a real application was demonstrated by analyzing the plating rinse water (pH 0.8), in which the Ca(2+), Na(+), Cr(VI)/Cr(III), Co(2+) and Zn(2+) were all detected by adjusting at pH 3.5 with 5% (v/v) diluent ammonia. Both the cations, e.g., K(+), Ca(2+), Na(+), Mg(2+), and the common high concentration anions in the sample, e.g., Cl(-), SO(4)(2-) and NO(3)(-) did not cause any disturbance to the concerned analytes.