Screening 5-lipoxygenase inhibitors from selected traditional Chinese medicines and isolation of the active compounds from Polygoni Cuspidati Rhizoma by an on-line bioactivity evaluation system.

To identify natural products as new prototypes for 5-lipoxygenase (5-LOX), 12 traditional Chinese medicines (TCMs) were selected for screening their 5-LOX inhibition activities. The results showed that the methanol extracts of all selected TCMs (n = 12) possessed inhibitory activities against 5-LOX at 200 µg/mL, of which six extracts of the TCMs showed significant inhibitory effects with IC50 values in the range from 33.2 ± 1.4 µg/mL to 153.5 ± 1.7 µg/mL, and the extract of Polygoni Cuspidati Rhizoma (RPC) was the most active sample. An on-line ultra-performance liquid chromatography-photodiode array-MSn -5-LOX-fluorescence detector (UPLC-PDA-MSn -5-LOX-FLD) method was applied to further identify the potential 5-LOX inhibitory constituents in RPC extracts, which resulted in the identification of seven components with 5-LOX-binding activities. Finally, four compounds (polydatin, resveratrol, emodin-8-O-glucoside, and emodin) were successfully purified from RPC extracts. The 5-LOX inhibition action was assayed in vitro, and the results showed that these compounds possessed potent inhibitory effects against 5-LOX with IC50 values of 15.3 ± 2.1, 4.5 ± 1.2, 23.8 ± 0.4, and 11.8 ± 1.5 µg/mL, respectively. This was the first study to reveal the 5-LOX inhibitory constituents of RPC, and the present investigation might provide a valuable approach for the rapid discovery of natural inhibitors from TCMs.

Quality markers of animal medicinal materials: Correlative analysis of musk reveals distinct metabolic changes induced by multiple factors.

BACKGROUND: Common farming environmental elements, such as longitude, latitude, and altitude, and physiological conditions, such as age and body weight, are thought to influence medicinal animal homeostasis and material quality by altering endocrine functions for primary and secondary metabolite formation. However, the currently available methods for evaluating complex components of traditional Chinese animal medicines have insufficient sensitivity and specificity. PURPOSE: Characterizing the primary/secondary metabolomes of medicinal animals is essential for understanding their material basis, controlling product quality, and reflecting on distribution interactions. Therefore, this study aimed to screen ecological- and physiological-related metabolites in captive Moschus berezovskii throughout the collection period based on the quality marker (Q-marker) concept. STUDY DESIGN AND METHODS: Fifty-one musk deer samples from 12 different distribution farms ranging in age from 2 to 11 years were enrolled. Differentially expressed musk metabolites were assessed via chromatography-tandem mass spectrometry technologies. A metabolome that mapped connections among these factors was established using chemometric and topological calculations. RESULTS: Statistical analysis revealed that muscone, cis-9-hexadecenal, antioxidant 2264, prasterone-3-sulfate, androstan-17-one, and 1,2-benzenedicarboxylic acid showed significantly altered expression. Partial least squares (PLS) regression analysis of qualified data for these 6 secondary metabolites (active components) demonstrated that age is the most important factor underlying the varying levels of muscone, androstan-17-one and 1,2-benzenedicarboxylic acid. Furthermore, weight was the most important factor for cis-9-hexadecenal, longitude was important for antioxidant 2264, latitude was important for prasterone-3-sulfate, and altitude was important for antioxidant 2264, androstan-17-one and 1,2-benzenedicarboxylic. Metabolite analysis within the MetaboAnalyst (MetPA) suite showed that 18 candidate biomarker metabolites were screened, including allantoin, glycine, serine, creatine, alanine, taurine, lactate, 2-oxoglutarate (2-OG), fumarate, proline, xanthine, cytosine, carnitine, arginine, threonine, aspartate, and urea. Metabolic network analysis showed 4 important pathways that were involved: arginine and proline metabolism, the urea cycle, aspartate metabolism, and glycine, serine and threonine metabolism. CONCLUSION: Using this combined metabolomic and chemometric approach, this study was successful in screening Q-markers for musk quality control and provided new insights into correlations among "ecological & physiological factors→Q-markers→metabolites", which potentially provides crucial information for musk breeding and material quality control.

Comparison of two species of Notopterygium by high-performance liquid chromatography-photodiode array detection-electrospray ionization tandem mass spectrometry.

Notopterygium incisum Ting ex H.T. Chang (N. incisum) and Notopterygium forbesii Boiss (N. forbesii) are two medicinal species of Qianghuo (a well-known traditional herbal medicine in China) that are widely used in clinical prescriptions for the treatment of colds and rheumatism. To compare the chemical constituents of these two plant materials, the phenolic constituents and coumarins of these two species were comprehensively and systematically analyzed by high-performance liquid chromatography-photodiode array detection-electrospray ionization tandem mass spectrometry (HPLC/DAD/ESI-MS(n)) for the first time. A total of 25 compounds (nine phenolic compounds and 16 coumarins) were detected in the methanol extracts. These compounds were separated on a C18 column and identified or tentatively characterized on the basis of their UV spectra and MS fragmentation behavior. In contrast to previous reports, we found that these two plant species possess very different coumarin patterns. O-Demethylfuropinnarin (18), phenethylferulate (19), notopterol (20), and isoimperatorin (22) were the predominant constituents of N. incisum, whereas nodakenin (6), 6-O-trans-feruloylnodakenin (12), p-hydroxypenethylanisate (16) and isoimperatorin (22) were the major constituents of N. forbesii. O-Demethylfuropinnarin (18), phenethylferulate (19) and notopterol (20) were only detected in N. incisum and can be regarded as useful taxonomic markers for differentiating these two plant species. Considering the marked differences in the main chemical constituents of N. incisum and N. forbesii, the biological activities of these two species should be further investigated and compared to ensure consistency and efficacy in the pharmaceutical applications of these materials.

Differentiation of four pairs of furocoumarin isomers by electrospray ionization tandem mass spectrometry.

A mass spectrometric method based on the combined use of electrospray ionization, collision-induced dissociation (CID) and ion-trap time-of-flight (IT-ToF) tandem mass spectrometry was used to identify four pairs of furocoumarin isomers. Our results show some characteristic mass spectrometric differences in isomeric furocoumarins. In the MS(2) spectra, the relative abundance ratios of m/z 131 [M + H - 2CO](+) to m/z 143 [M + H - CO(2)](+) and m/z 115 [M + H - CO-CO(2)](+) of psoralen are less than one, but both ratios are greater than one in the case of isopsoralen. The relative abundance of m/z 159 [M + H - CO(2)](+) is much higher than that of m/z 175 [M + H - CO](+) in the case of bergaptol, but this trend is reversed in xanthotoxol. Moreover, three diagnostic ions of m/z 189 [M + H - CO](+), m/z 185 [M + H - CH4O](+) and m/z 161 [M + H - 2CO](+) are observed in the MS(2) spectrum of xanthotoxin but not in that of bergapten. Further, two diagnostic ions of m/z 226 [M - H - CH(3) - CO](-) and m/z 210 [M - H - CH(3) - CO(2)](-) are observed in the MS(2) spectrum of isoimperatorin but not in that of imperatorin. The relative abundance of product ions associated with some diagnostic ions can be used to characterize furocoumarin isomers.

[Determination of gold in geological sample by inductively coupled plasma mass spectrometry after carbon nanofibers separation and preconcentration].

A novel method for the determination of Au by inductively coupled plasma mass spectrometry (ICP-MS) is described. Au can be separated and preconcentrated with a micro-column packed with carbon nanofibers as an adsorption material. The adsorption and elution behaviors of Au3+ on carbon nanofibers were systematically investigated under dynamic conditions. The experimental results showed that the studied ions can be adsorbed quantitatively at pH 2.0, and the analytes adsorbed on the column can be eluted with H2NCSNH2-HCl solution at pH 1.0. Under the optimum conditions, the detection limits for Au is 0.15 ng x mL(-1), and the relative standard deviation (RSD) is 8.5% (n = 6). The proposed method has been applied to the determination of trace Au in geological standard material with satisfactory results.

[Studies on chemical constituents of aerial parts of Ammopiptanthus mongolicus].

OBJECTIVE: To investigate the chemical constituents of the aerial parts of Ammopiptanthus mongolicus. METHOD: The chemical constituents were isolated by various column chromatographic methods. The structures were identified by spectral data. RESULT: Ten compounds were isolated and identified as m-hydroxybenzoic acid (1), 1-(4-hydroxyphenyl) ethanone (2), beta-sitosterol (3), (-)-syringaresinol (4), (+)-lariciresinol (5), blumenol A (6), blumenol B (7), beta-daucosterol (8), coniferin (9), syringin (10). CONCLUSION: The ten compounds were obtained from the genus Ammopiptanthus for the first time.

[Slurry sampling for direct determination of trace cadmium in amber by graphite furnace atomic absorption spectrometry].

A method for the direct determination of trace cadmium in amber by graphite furnace atomic absorption spectrometry (GFAAS) with slurry sampling was described. Palladium nitrate was used as a matrix modifier to eliminate the interference. Slurry stability and the influences of the matrix modifier, ashing/atomization temperature and coexistent ions on analytical signals were investigated in detail. Under the optimized experimental conditions, the detection limit of this method was 9.4 ng x g(-1) with a precision of 6.1%.

Honokiol inhibits arterial thrombosis through endothelial cell protection and stimulation of prostacyclin.

AIM: To study the effect of honokiol on arterial thrombosis and endothelial cells. METHODS: Rabbit platelet aggregation was performed with Borns turbid method. Thrombosis was produced by the endothelial injury stimulated with electric current. Rat aortic endothelial cells (RAEC) were cultured and cell viability was assessed using the MTT assay. Nitric oxide (NO) concentrations in serum-free media of RAEC were determined using the kinetic cadmium-reduction method. The stable metabolite prostacyclin was measured in serum-free media of RAEC by radioimmunoassay. RESULTS: Honokiol (37.6-376 micromol/L) decreased rabbit platelet aggregation in vitro in a concentration-dependent manner, while intravenously injection of honokiol (0.12-12 microg/kg) significantly inhibited rabbit platelet aggregation induced by collagen ex vivo. In the electrical current-stimulated carotid thrombosis model in rats, honokiol (5-50 microg/kg, iv) prolonged the thrombus occlusion time in a does-dependent manner. In vitro honokiol (0.376-37.6 micromol/L) effectively protected cultured RAEC against oxidized low density lipoprotein (ox-LDL) injury, and significantly increased 6-keto-PGF1alpha (the stable metabolite of prostacyclin) in serum-free media of RAEC. Honokiol also increased NO level in RAEC serum-free medium at a lower concentration range (0.0376-0.376 micromol/L), but honokiol 3.76 micromol/L decreased NO level. CONCLUSION: Honokiol is a potent arterial thrombosis inhibitor. Endothelial cell protection and the stimulation of prostacyclin release may be its main anti-thrombosis mechanism. Stimulation of NO release in endothelial cells may play a role, but it is not a key factor.

[Determination of Fe, Al and Ni in ZrO2 by electrothermal vaporization ICP-AES].

A novel method for the analysis of ZrO2 powder via in-situ separation of the matrix from the analytes is described, based on the use of a polytetrafluorethylene (PTFE) emulsion as a chemical modifier. The main affecting factors, including the flow rate of carrier gas and auxiliary carrier gas, ashing temperature and time, matrix concentration, signal record time, and vaporization temperature and time, were investigated systematically. Under the optimum operating conditions, the detection limits (DL) of analytes vary from 4.2 ng x mL(-1) (Al) to 11 ng x mL(-1)(Fe). The relative standard deviations (RSDs) are 3.1%-4.9%.

[Pharmacokinetics of honokiol in rats].

OBJECTIVE: To investigate the pharmacokinetics of honokiol in rats. METHODS: Honokiol injection was delivered by vein injection to SD-rats. The blood samples were gathered at a series of time lags. Honokiol in rat plasma was determined with an RP-HPLC method and the data were analyzed with program 3P87. RESULTS: After i.v. injection of honokiol, concentration-time curves were fitted to a 3-compartment model: with halftime of 2.8 min, 11.9 min, and 56.8 min. CONCLUSION: Honokiol was quickly distributed in rats after i.v. and the concentration decreased rapidly. Our studies provided important referrence to the research on the pharmacodynamics and the pharmaceutics of Honokiol.

[Direct determination of trace elements in human serum by electrothermal vaporization ICP-AES].

A method for direct determination of trace elements in human serum by electrothermal vaporization inductively coupled plasma atomic emission spectrometry (ETV-ICP-AES) with slurry sampling was developed. A polytetrafluoroethylene (PTFE) emulsion was used as a fluorinating agent to promote the vaporization of the analytes from graphite furnace, resulting in a remarkable improvement of analytical performances for the recommended method. The main factors affecting emission signals of the interested elements were investigated. The detection limits of 1.4 ng x mL(-1) for Cu and 2.9 ng x mL(-1) for Fe were achieved, and the precisions expressed as relative standard deviation (RSD) were less than 6.0% after optimization of the operating conditions.

[Direct determination of trace arsenic in coal by slurry-sampling graphite-furnace atomic absorption spectrometry].

A method for direct determination of trace arsenic in coal by slurry-sampling Graphite-Furnace Atomic Absorption Spectrometry (GFAAS) was developed, using Pd as a matrix modifier. The effects of slurry stability, particle size of sample, matrix modifiers, ashing temperature, atomization temperature, and common coexisting components on the signal intensity of arsenic were investigated. Under optimized operating conditions, the detection limits and relative standard deviation of this method were 0.054 microg x g(-1) and 8.9%, respectively.

Blockade of paeoniflorin on sodium current in mouse hippocampal CA1 neurons.

AIM: To study the blockade of paeoniflorin (Pae) on I(Na) in the acutely isolated hippocampus neurons of mice. METHODS: The whole-cell patch clamp technique was used. RESULTS: Pae inhibited I(Na) in frequency-dependent and concentration-dependent manners, with an IC50 of 271 micromol/L. Pae 0.3 mmol/L shifted the activation potential of the maximal I(Na) from -40 mV to -30 mV, shifted the steady-state activation and inactivation curves toward more positive and negative potentials by 10.8 mV, and 18.2 mV, respectively, and postponed the recovery of I(Na) inactivation state from (4.2+/-0.7) ms to (9.8+/-1.2) ms. CONCLUSION: Pae inhibited I(Na) in mouse hippocampus neurons.

[Direct analysis of trace elements in tobacco using electrothermal vaporization ICP-AES].

A method for direct analysis of trace elements (Cu, Fe, Al, Cr and Mn) in tobacco by slurry sampling electrothermal vaporization (ETV) ICP-AES using polytetrafluoroethylene (PTFE) emulsion as a chemical modifier was described. The main factors affecting the analytical signals were studied. The detection limits of this method for the determination of the interesting elements were in the range of 3.8 ng.mL-1 (Cu) to 13 ng.mL-1 (Fe), and the relative standard deviations (RSD) varied from 2.5% (Cu) to 5.7% (Cr) with the recoveries of 91.0%-112%.

[Determination of cichoric acid in Echinacea purpuea].

OBJECTIVE: To analyze the natural change rule of active components of E. purpuea by measuring content of cichoric acid. METHOD: Reverse HPLC method was used. RESULT: The maximum cichoric acid content of the roots occured in seedling age of May, and that of the flowers occured in blooming stage of mid July, but cichoric acid in stems was generally low anyway. The maximum content of cichoric acid in the plant above ground occured in the blooming stage of mid July. CONCLUSION: The measuring method of content of cichoric acid is successful and reliable. The optimum stage of harvest in Echinacea purpuea should be guided by natural change rule of cichoric acid content.

[Variation of endogeneous ET, CGRP and NO in myocardial ischemia in rats and the regulatory effect of xinshuping].

OBJECTIVE: To observe the variation of ET and CGRP contents in ischemic heart, and NO level in serum of myocardial damaged rats, and their regulation when with the protection of Xinshuping, a traditional Chinese medicine compound. METHOD: The models of myocardial ischemia were prepared by subcutaneous injection of isoproterenol or by ligation of coronary artery. RESULT: ET content in myocardium was significantly increased (P < 0.01), and CGRP content as well as NO level in serum was not changed obviously in the model induced by isoproterenal. However, NO level in serum of rats treated with Xinshuping (ig bid x 2.5 d) was markedly raised (P < 0.01), neither ET not CGRP contents were affected by it. LDH and CK levels in serum of rats were evidently lowered by Xinshuping treatment. S-T segment's elevation of ECG was significantly inhibited and myocardial infarction size was reduced markedly by Xinshuping treatment in rats subjected to coronary artery ligature. CONCLUSION: ET, CGRP or NO is involved in myocardial infarction caused by isoproterenol. The ischemic damage or dysfunction in different models is obviously protected by Xinshuping. The promotion of NO release from vascular endothelium is probably related with this protective effect.