Human Milk Endocannabinoid Levels as a Function of Obesity and Diurnal Rhythm

The endocannabinoid system is involved in the regulation of a variety of physiological and cognitive processes. While the endocannabinoids 2-arachidonoylglycerol (2-AG) and anandamide (N-arachidonoylethanolamine, AEA) have been found in breast milk, their role(s) have yet to be determined. This study determined the normal concentration ranges of endocannabinoids (2-AG and AEA) in breast milk and the influences, if any, of obesity and diurnal rhythms on their levels. Milk samples were collected from 36 breastfeeding mothers at 4–8 weeks postpartum at each feed over a 24-h period, and further stratified into three groups based on body mass index (BMI). The samples were analyzed using liquid chromatography mass spectrometry. AEA was below the limit of detection and 2-AG levels averaged 59.3 ± 18.3 ng/mL (± SD) in women with normal BMI. Wide-ranging 2-AG concentrations in the overweight (65.5 ± 41.9 ng/mL) /obese (66.1 ± 40.6 ng/mL) groups suggest BMI may be a contributing factor influencing its levels. Following a diurnal pattern, there was a significantly higher 2-AG concentration observed during the day, as compared to night time samples. In conclusion, our study clearly suggests that appropriate milk collection and storage conditions are critical. Further, body weight and diurnal rhythm appear to influence levels of 2-AG. Based on these results, future studies are underway to determine what specific roles endocannabinoids may play in human milk and how elevated levels of 2-AG may modulate infant appetite and health.

BIONOTE as an Innovative Biosensor for Measuring Endocannabinoid Levels

In this study, a novel approach was developed to quantify endocannabinoids (eCBs), and was based on the liquid biosensor BIONOTE. This device is composed of a probe that can be immersed in a solution, and an electronic interface that can record a current related to the oxy-reductive reactions occurring in the sample. The two most representative members of eCBs have been analysed in vitro by BIONOTE: anandamide (N-arachidonoylethanolamine, AEA) and 2-arachidonoylglycerol (2-AG). Bovine serum albumin was used to functionalize the probe and improve the sensibility of the whole analytical system. We show that BIONOTE is able to detect both AEA and 2-AG at concentrations in the low nanomolar range, and to discriminate between these eCBs and their moieties arachidonic acid, ethanolamine and glycerol. Notably, BIONOTE distinguished these five different molecules, and it was also able to quantify AEA in human plasma. Although this is just a proof-of-concept study, we suggest BIONOTE as a cheap and user-friendly prototype sensor for high throughput quantitation of eCB content in biological matrices, with an apparent diagnostic potential for tomorrow’s medicine.

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.

A micro salting-out assisted liquid-liquid extraction combined with ultra-high performance liquid chromatography tandem mass spectrometry to determine anandamide and 2-arachidonoylglycerol in rat brain samples

A simple and reliable method was developed and validated to determine the endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG) in rat brain samples by micro salting-out assisted liquid-liquid extraction combined with ultra-high performance liquid chromatography tandem mass spectrometry (SALLLE/UHPLC-MS/MS). The SALLE parameters (brain homogenate volume, salting-out agent, salt concentration, salt solution volume, organic solvent, organic solvent volume, and centrifugation temperature) were optimized to improve sensitivity and selectivity of the method. The SALLE/UHPLC-MS/MS method presented linear ranges from 2.00 to 20.00 ng mL^-1 for AEA and from 0.300 to 10.00 μg mL^-1 for 2-AG, no significant matrix effect, and inter- and intra-assay precision and accuracy with CV and RSE values lower than 15%, respectively. This innovative method was successfully applied to determine AEA and 2-AG in brain hemispheres from a 6-OHDA animal model of Parkinson's disease (PD).

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.

Essential fatty acids deficient diet modulates N-Acylethanolamide profile in rat's tissues

No data are available on whether a diet deficient of the essential fatty acids is able to modulate tissue levels of endocannabinoids and congeners. Male rats fed for 12 weeks a diet deficient of essential fatty acids, palmitic and oleic acids (EFAD), replaced with saturated fatty acids (SAFA), showed lowered n-3 and n-6 PUFAs levels in plasma, liver and adipose tissue, with concomitant steep increase of oleic and mead acids, while in hypothalamus no changes in PUFA concentration were detected and only palmitoleic acid was found increased. We found a reduction of anandamide and palmitoylethanolamide in liver and brain, while oleoylethanolamide increased significantly in liver and adipose tissue, associated to a 50 % body weight decrease. Changes in N-acylethanolamide profile may contribute to body weight reduction distinctive of EFA deficiency.

Antifungal and anti-aflatoxigenic activity of Heliopsis longipes roots and affinin/spilanthol against Aspergillus parasiticus by downregulating the expression of alfD and aflR genes of the aflatoxins biosynthetic pathway

In the present study, ethanolic extract from Heliopsis longipes roots and affinin/spilanthol against Aspergillus parasiticus growth and aflatoxins production were studied in relation to the expression of aflD and aflR, two key genes of aflatoxins biosynthetic pathway. Phytochemical analysis of the ethanolic extract by GC-EIMS identified affinin/spilanthol (7.84 ± 0.27 mg g^-1) as the most abundant compounds in H. longipes roots. The antifungal and anti-aflatoxigenic assays showed that affinin/spilanthol at 300 µg mL^-1 produced the higher inhibition of radial growth (95%), as well as, the higher aflatoxins production inhibition (61%) in comparison to H. longipes roots (87% and 48%, respectively). qRT-PCR revealed that the expression of aflD and aflR genes showed a higher downregulation in affinin/spilanthol at 300 µg mL^-1. The expression ratio of alfD was suppressed by affinin/spilanthol in 79% and aflR in 84%, while, a lower expression ratio suppressed by H. longipes was obtained, alfD (55%) and aflR (59%). Affinin/spilanthol possesses higher antifungal and anti-aflatoxigenic activity against A. parasiticus rather than H. longipes roots, and this anti-aflaxotigenic activity occurring via downregulation of the aflD and aflR genes. Thus, H. longipes roots and affinin/spilanthol can be considered potent antifungal agents against aflatoxigenic fungus, especially, affinin/spilanthol.

Characterization of stable and reactive metabolites of piperine formed on incubation with human liver microsomes

Black pepper, though commonly employed as a spice, has many medicinal properties. It consists of volatile oils, alkaloids, pungent resins, etc., of which piperine is a major constituent. Though safe at low doses, piperine causes alteration in the activity of drug metabolising enzymes and transporters at high dose and is known to precipitate liver toxicity. It has a potential to form reactive metabolite(s) (RM) owing to the presence of structural alerts, such as methylenedioxyphenyl (MDP), α, β-unsaturated carbonyl group (Michael acceptor), and piperidine. The present study was designed to detect and characterize stable and RM(s) of piperine formed on in vitro incubation with human liver microsomes. The investigation of RMs was done with the aid of trapping agents, viz, glutathione (GSH) and N-acetylcysteine (NAC). The samples were analysed by ultra-high performance liquid chromatography coupled with high resolution mass spectrometry (UHPLC-HRMS) using Thermo Scientific Q Exactive Plus Orbitrap. Full scan MS followed by data-dependent MS² (Full MS-ddMS² ) mode was used to establish mass spectrometric fragmentation pathways of protonated piperine and its metabolites. In total, four stable metabolites and their isomers (M1a-c, M2a-b, M3a-c, and M4a-b) were detected. Their formation involved removal of carbon (3, M1a-c), hydroxylation (2, M2a-b), hydroxylation with hydrogenation (3, M3a-c), and dehydrogenation (2, M4a-b). Out of these metabolites, M1, M2, and M3 are reported earlier in the literature, but their isomers and two M4 variants are novel. In addition, six novel conjugates of RMs, including three GSH conjugates of m/z 579 and three NAC conjugates of m/z 435, were also observed.

Development and Validation of a High-Performance Thin-Layer Chromatographic (HPTLC) Method for Simultaneous Quantification of Reserpine, Atropine, and Piperine in Sarpagandha Ghanvati, a Classical Ayurvedic Preparation

Background: Anxiety disorders are the most common of emotional disorders, affecting more than 20 million people annually. Sarpagandha Ghanvati is a classical Ayurvedic polyherbal formulation prescribed in conditions of insomnia, hysteria, and is used as an anxiolytic agent. Standardization and quality control are the two major issues that need to be addressed for herbal formulations, especially those containing multiple herbal ingredients. Objective: An HPTLC method was developed for the simultaneous quantification of reserpine, atropine, and piperine from Sarpagandha Ghanvati containing Rauwolfia serpentine (root), Hyoscyamus niger (seed), and Piper longum (root and stem). Methods: The marker compounds were effectively resolved on a silica gel G TLC plate using toluene-ethyl acetate-diethyl amine (7+2+1, v/v) as the mobile phase. The detected wavelengths for reserpine, atropine, and piperine were 269, 220, and 254 nm, respectively. The method was validated as per the International Conference on Harmonization guidelines. Results: R. serpentine roots contained 0.82% w/w of reserpine. Atropine content in the seeds of H. niger was found to be 0.004% w/w, whereas P. longum roots were found to contain 0.508% of piperine. The method was found to be accurate, which was evident from 98.93, 99.46, and 99.10% recovery of reserpine, atropine, and piperine, respectively, when the respective herbs were spiked with them. By the developed HPTLC method, 1.0 g of Sarpagandha Ghanvati was found to contain 4.94, 0.049, and 0.318 mg of reserpine, atropine, and piperine, respectively. The recoveries of these three markers from the formulation were found to be 90.32, 92.45, and 89.97%, respectively. Conclusions: The developed method can be successfully used for simultaneous estimation of these marker compounds and for the quality control of the classical Ayurvedic formulation Sarpagandha Ghanvati. Highlights: This works describes effects of extraction solvents on the quantities of marker compounds in the formulations. It also suggests a simple and reliable HPTLC method for simultaneous quantification of three different marker compounds from a poly-herbal formulation.

Harvest Strategies for Optimization of the Content of Bioactive Alkamides and Caffeic Acid Derivatives in Aerial Parts and in Roots of Echinacea purpurea

Aerial parts and roots of Echinacea purpurea were harvested consecutively in order to find the best strategy for harvest of both types of plant material for an optimal content of bioactive alkamides and caffeic acid derivatives. Four caffeic acid derivatives and 15 alkamides were identified and quantified. The aerial parts were harvested in bud, bloom, and wilting stage and the roots were harvested 1 week, 1 month, and 3 months after each harvest of aerial parts. The highest yield per area of both alkamides and caffeic acid derivatives is achieved when the aerial parts are harvested late (wilting stage). To obtain an optimal content of alkamides and caffeic acid derivatives it is not recommendable to harvest the aerial parts and the roots in the same year. If the aerial parts must be harvested, the roots should be harvested 1 week after because this will result in the most optimal concentration of bioactive compounds in both products.

Reduced levels of the endocannabinoid arachidonylethanolamide (AEA) in hair in patients with borderline personality disorder - a pilot study

Endocannabinoids are involved in depressive and anxious symptoms and might play a role in stress-associated psychiatric disorders. While alterations in the endogenous cannabinoid system have been repeatedly found in patients with posttraumatic stress disorder (PTSD), this system has been mostly neglected in borderline personality disorder (BPD). However, there is first evidence for elevated serum levels of the endocannabinoids arachidonylethanolamide (AEA) and 2-arachidonyl-sn-glycerol (2-AG) in BPD patients compared to healthy controls and PTSD patients. In this study, hair endocannabinoids were analyzed, reflecting long-term endocannabinoid concentrations. We assessed AEA concentrations as well as 2-AG and the 2-AG main isomer 1-AG (1-AG/2-AG) in hair in women with BPD (n = 15) and age- and education-matched healthy women (n = 16). We found significantly reduced log AEA in BPD patients compared to healthy women (p = .03) but no differences in log 1-AG/2-AG concentrations. In addition, there was no association between 1-AG/2-AG and hair cortisol, but we found a non-significant correlation between hair concentrations of AEA and cortisol (p = .06). Our data indicate altered long-term release of endogenous cannabinoids in women with BPD depending on type of endocannabinoid. AEA has been suggested to modulate the basal activity of the endocannabinoid system and seems to attenuate depressive and anxious symptoms. Thus, chronically reduced AEA might contribute to psychiatric symptoms in BPD.

Effects of tumour necrosis factor α upon the metabolism of the endocannabinoid anandamide in prostate cancer cells

Tumour necrosis factor α (TNFα) is involved in the pathogenesis of prostate cancer, a disease where disturbances in the endocannabinoid system are seen. In the present study we have investigated whether treatment of DU145 human prostate cancer cells affects anandamide (AEA) catabolic pathways. Additionally, we have investigated whether cyclooxygenase-2 (COX-2) can regulate the uptake of AEA into cells. Levels of AEA synthetic and catabolic enzymes were determined by qPCR. AEA uptake and hydrolysis in DU145 and RAW264.7 macrophage cells were assayed using AEA labeled in the arachidonic and ethanolamine portions of the molecule, respectively. Levels of AEA, related N-acylethanolamines (NAEs), prostaglandins (PG) and PG-ethanolamines (PG-EA) in DU145 cells and medium were quantitated by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis. TNFα treatment of DU145 cells increased mRNA levels of PTSG2 (gene of COX-2) and decreased the mRNA of the AEA synthetic enzyme N-acyl-phosphatidylethanolamine selective phospholipase D. mRNA levels of the AEA hydrolytic enzymes fatty acid amide hydrolase (FAAH) and N-acylethanolamine-hydrolyzing acid amidase were not changed. AEA uptake in both DU145 and RAW264.7 cells was inhibited by FAAH inhibition, but not by COX-2 inhibition, even in RAW264.7 cells where the expression of this enzyme had greatly been induced by lipopolysaccharide + interferon γ treatment. AEA and related NAEs were detected in DU145 cells, but PGs and PGE2-EA were only detected when the cells had been preincubated with 100 nM AEA. The data demonstrate that in DU145 cells, TNFα treatment changes the relative expression of the enzymes involved in the hydrolytic and oxygenation catabolic pathways for AEA. In RAW264.7 cells, COX-2, in contrast to FAAH, does not regulate the cellular accumulation of AEA. Further studies are necessary to determine the extent to which inflammatory mediators are involved in the abnormal endocannabinoid signalling system in prostate cancer.

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.

Characteristic fingerprinting based on macamides for discrimination of maca (Lepidium meyenii) by LC/MS/MS and multivariate statistical analysis

BACKGROUND

Macamides with a benzylalkylamide nucleus are characteristic and major bioactive compounds in the functional food maca (Lepidium meyenii Walp). The aim of this study was to explore variations in macamide content among maca from China and Peru. Twenty-seven batches of maca hypocotyls with different phenotypes, sampled from different geographical origins, were extracted and profiled by liquid chromatography with ultraviolet detection/tandem mass spectrometry (LC-UV/MS/MS).

RESULTS

Twelve macamides were identified by MS operated in multiple scanning modes. Similarity analysis showed that maca samples differed significantly in their macamide fingerprinting. Partial least squares discriminant analysis (PLS-DA) was used to differentiate samples according to their geographical origin and to identify the most relevant variables in the classification model. The prediction accuracy for raw maca was 91% and five macamides were selected and considered as chemical markers for sample classification.

CONCLUSION

When combined with a PLS-DA model, characteristic fingerprinting based on macamides could be recommended for labelling for the authentication of maca from different geographical origins. The results provided potential evidence for the relationships between environmental or other factors and distribution of macamides. © 2016 Society of Chemical Industry.

[Study on the Extraction, Geometry Structure and Spectral Characterization of Piperine Alkaloid]

Using pepper fruit of Hainan as raw material and 95% ethanol as solvent, the alkaloid in pepper is extracted with reflux method in this paper. The piperonylic acid is removed by adjusting the pH; the fat-soluble substance being removed by adding ethyl ether; the piperine alkaloid being purified with acetone by recrystallization anddetected with HPLC, as well as characterized with IR. The characterizations of piperine are discussed. Meanwhile, B3LYP/6-31G (d,p) method of DFT is applied to optimize the structure, calculate frequency and energy of pepper alkaloid, then obtain four kinds of configurations (configuration Ⅰ as Piperine, configuration Ⅱ as Iso Piperine, configuration Ⅲ as Iso Chavicine, configuration Ⅳ as Chavicine) with 64 kinds of stability conformational structure. The distribution of the thermodynamic equilibrium of stable conformations of four kinds of configurations of the molecular is calculated with Gibbs free energy at room temperature (298.15 K). And IR spectra of the experimental were compared with the IR spectra of the theoretical. The results show that the alkaloid extracted from pepper is mainly conformer 1 in configuration Ⅰ, that is, Piperine; after purifying, the content of piperine is 7% with the purity of 99%. With analysis, the methods of extraction, separation and purification of piperine in this paper achieve good results. Established models are in good agreement with the experimental results. This research is of great significance in guiding extracting process, building structural model and the characterization and application of piperine.

A robust capillary liquid chromatography/tandem mass spectrometry method for quantitation of neuromodulatory endocannabinoids

RATIONALE

Methods for quantifying anandamide (AEA) and 2-arachidonoyl glycerol (2-AG) are needed to support programs investigating molecular mechanisms of the central nervous system. Existing methods, while useful, are not well adapted to efficiently process large numbers of very small tissue samples. A unique challenge involves the disparity in endogenous levels of AEA (pmol/g tissue) and 2-AG (nmol/g tissue).

METHODS

A simplified one-step solvent extraction procedure was developed for recovering endocannabinoids from rat brain tissues, and combined with capillary liquid chromatography/tandem mass spectrometry (LC/MS/MS). Various multiple reaction monitoring (MRM)-based methods were evaluated for limit of detection (LOD) and robustness.

RESULTS

The optimized simultaneous quantitation method achieves an LOQ of 50 amol for AEA and 25 fmol for 2-AG, both with a linearity over 3 orders of magnitude, and elution times under 3 min. Accuracy, expressed as relative error (RE), is less than 12% for AEA and less than 6% for 2-AG. Precision, expressed as relative standard deviation (RSD), is less than 6% for AEA and less than 3% for 2-AG. Sample handling routines are sufficiently robust to support the automated analysis of thousands of samples from a range of tissue types.

CONCLUSIONS

The microscale method is a sensitive, economical and robust alternative to the larger scale LC/MS methods currently implemented for quantitation of AEA and 2-AG.

Development and validation of simultaneous estimation method for curcumin and piperine by RP-UFLC

Curcumin and piperine are proven for their potent medicinal benefits to treat various diseases and they are most commonly used combination in various Indian systems of medicine such as Ayurveda, Siddha and Unani. The objective of the present work is to develop a simultaneous estimation of curcumin and piperine by reverse phase Ultra-fast liquid chromatographic (RP-UFLC) method. The chromatographic separation was performed on a C8 column (250 x 4.6 mm, 5µ i.d.) stationary phase using a mobile phase of 25mM potassium dihydrogen ortho phosphate buffer (pH 3.5) and acetonitrile (30: 70 v/v) at a flow rate of lml/min at detection wave length of 280nm. The calibration curve was plotted in the concentration range of 0-2200ng/ml and found to be linear for both curcumin (r(2)=0.996) and piperine (r(2)=0.999). The method was validated for parameters such as accuracy, sensitivity, precision, linearity, specificity, ruggedness and robustness as per ICH guidelines. The developed simple, precise and specific method can be used as a quality control tool for qualitative and quantitative estimation of curcumin and piperine in various food products, herbal medicines and nutraceuticals.

Antiprotozoal activity of Achillea ptarmica (Asteraceae) and its main alkamide constituents

In the course of our ongoing screening of plants of the family Asteraceae for antiprotozoal activity, a CH₂Cl₂-extract from the flowering aerial parts of Achillea ptarmica L. (sneezewort yarrow) was found to be active in vitro against Trypanosoma brucei rhodesiense (IC₅₀ = 0.67 µg/mL) and Plasmodium falciparum (IC₅₀ = 6.6 μg/mL). Bioassay guided fractionation led to the isolation and identification of five alkamides from the most active fractions. Pellitorine and 8,9-Z-dehyropellitorine are the main components of the extract. Beside these olefinic acid amides, four alkamides with diene-diyne structures were isolated. All alkamides were tested for antiprotozoal activity in vitro. Pellitorine was the most active compound so far within this study against P. falciparum (IC₅₀ = 3.3 µg/mL), while 8,9-Z-dehydropellitorine was most active against T. b. rhodesiense (IC₅₀ = 2.0 µg/mL). The activity of pure pellitorine against Plasmodium is higher than that of the crude extract and thus explains the activity of the latter. None of the isolated alkamides, however, was as active against T. b. rhodesiense as the crude extract whose antitrypanosomal activity must therfore be due to a synergistic effect of the isolated compounds or to more active yet to be identified constituents.

HPTLC method for simultaneous determination of piperine, embeline, and carvone in the ayurvedic formulation Catpusphadhya churna

Churnas are an important group of formulations used by traditional physicians to treat various types of diseases. The principle of using a churna is based on the fact that the therapeutic value of most substances greatly increases when they are reduced to a very fine state of subdivision. Catpusphadhya churna, as per the Ayurvedic system of Indian medicine, is used for acute rheumatoid arthritis. In the present study, an attempt was made to develop an HPTLC method for the quantitative determination of piperine, embeline, and carvone in a laboratory-prepared formulation. Raw materials used in formulations were obtained from two different suppliers and were subjected to methanol extractions by using a Soxhlet apparatus. Piperine, embeline, and carvone were quantified in the extracts by using HPTLC. The detection and quantification were performed at 254 nm. The formulation contained 2.35% (w/w) of piperine, 4.86% (w/w) of embeline, and 1.48% (v/w) of carvone. Linearity studies indicated that piperine, embeline, and carvone were in the linear ranges, while the recovery studies revealed a recovery of 99.32% (w/w) of piperine, 101.82% (w/w) of embeline, and 100.09% (v/w) of carvone, thus proving the accuracy of the analysis. The developed HPTLC method resolved and quantified piperine, embeline, and carvone effectively, so it could be an important method for the QC of polyherbal formulations.

Occurrence of piperidine alkaloids in Piper species collected in different areas

A simple and convenient method was established for simultaneous quantitative determination of piperine and piperlonguminine in dried fruits of Piper longum and allied plants. The average content of piperine in P. longum (18.26 mg/g, range 12.05-33.23 mg/g) was about one half that of P. nigrum (40.09 mg/g, range 29.57-54.23 mg/g), but the content of piperlonguminine in P. longum was in the range of 0.42-1.82 mg/g, and the average content of piperlonguminne (0.91 mg/g) was about seven times higher than that in P. nigrum (0.13 mg/g). A sample of P. longum from Vietnam and a sample of P. retrofractum collected in Ishigaki, Japan, showed high contents of piperine and piperlonguminine. On the other hand, a sample of P. betle collected in Taiwan showed low content of piperine, and piperlonguminine was not detected.

Evaluation of unsaturated alkanoic acid amides as maskers of epigallocatechin gallate astringency

Some foods, beverages, and food ingredients show characteristic long-lasting aftertastes. The sweet, lingering taste of high intensity sweeteners or the astringency of tea catechins are typical examples. Epigallocatechin-3-gallate (EGCG), the most abundant catechin in green tea, causes a long-lasting astringency and bitterness. These sensations are mostly perceived as aversive and are only accepted in a few foods (e.g., tea and red wine). For the evaluation of the aftertaste of such constituents over a certain period of time, Intensity Variation Descriptive Methodology (IVDM) was used. The approach allows the measurement of different descriptors in parallel in one panel session. IVDM was evaluated concerning the inter- and intraindividual differences of panelists for bitterness and astringency of EGCG. Subsequently, the test method was used as a screening tool for the identification of potential modality-selective masking compounds. In particular, the intensity of the astringency of EGCG (750 mg kg(-1)) could be significantly lowered by 18-33% during the time course by adding the trigeminal-active compound trans-pellitorine (2E,4E-decadienoic acid N-isobutyl amide 1, 5 mg kg(-1)) without significantly affecting bitterness perception. Further, structurally related compounds were evaluated on EGCG to gain evidence for possible structure-activity relationships. A more polar derivative of 1, (2S)-2-[[(2E,4E)-deca-2,4-dienoyl]amino]propanoic acid 9, was also able to reduce the astringency of EGCG similar to trans-pellitorine but without showing the strong tingling effect.

Quantitative analysis of multiple fatty acid ethanolamides using ultra-performance liquid chromatography-tandem mass spectrometry

Fatty acid ethanolamides (FAE) represent a group of lipid signaling molecules associated with many physiological and pharmacological actions; however, low FAE tissue levels pose challenges in terms of analytical characterization. The objective was to develop a competent ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for analysis of multiple FAE in animal and human tissue samples. Analytes were extracted using lipid-phase and solid-phase extraction procedures. Chromatographic separation was achieved using a gradient elution in 8 min. FAE were quantified by MS/MS in positive electrospray ionization mode. Linearity was shown in lower and higher FAE concentration ranges, with a limit of quantification (LOQ) ≤0.2 ng/ml for FAE including alpha-linolenoylethanolamide (ALEA), arachidonoylethanolamide (AEA), docosahexaenoylethanolamide (DHEA), linoleoylethanolamide (LEA), oleoylethanolamide (OEA) and palmitoylethanolamide (PEA). Accuracy was shown to be between 92.4% and 108.8%, and precision was <10% for all FAE species. In sum, this sensitive and reproducible method can be used to simultaneously determine multiple FAE at low concentrations in order to facilitate further study of the role of FAE on physiological state.

Ectopic pregnancy is associated with high anandamide levels and aberrant expression of FAAH and CB1 in fallopian tubes

CONTEXT

Ectopic pregnancy is associated with significant morbidity and mortality, but the molecular mechanisms underlying this condition remain unclear. Although the endocannabinoids, N-arachidonoylethanolamine (anandamide), N-oleoylethanolamine, and N-palmitoylethanolamine, are thought to play a negative role in ectopic pregnancy, their precise role(s) within the fallopian tube remains unclear. Anandamide activates cannabinoid receptors (CB1 and CB2) and, together with its degrading [e.g. fatty acid amide hydrolase (FAAH)] and synthesizing enzymes (e.g. N-acyl-phosphatidylethanolamine-specific phospholipase D), forms the endocannabinoid system. High anandamide levels are associated with tubal arrest of embryos in mice and may have a similar role in women.

OBJECTIVE

The aims were to quantify the levels of the endocannabinoids and evaluate the expression of the modulating enzymes and the cannabinoid receptors in fallopian tubes of women with ectopic pregnancy compared to those of nonpregnant women.

DESIGN AND SETTING

We conducted a prospective study at the University Hospitals of the Leicester National Health Service Trust.

PARTICIPANTS AND METHODS

Fallopian tubes collected from women with ectopic pregnancy and nonpregnant women with regular menstrual cycles were used for quantification of endocannabinoids by ultra-HPLC tandem mass spectrometry, were fixed in formalin for immunohistochemistry, and had RNA extracted for RT-quantitative PCR or protein extracted for immunoblotting.

RESULTS

Anandamide, but not N-oleoylethanolamine and N-palmitoylethanolamine, levels were significantly higher in ectopic fallopian tubes. Endocannabinoid levels from isthmus to ampulla were not significantly different. Cannabinoid receptors and endocannabinoid modulating enzymes were localized in fallopian tube epithelium by immunohistochemistry and showed reduced CB1 and FAAH expression in ectopic pregnancy.

CONCLUSION

High anandamide levels and reduced expression of CB1 and FAAH may play a role in ectopic implantation.

[Effects of anandamide on IL-11 production through the TRPV1 of human periodontal ligament cells]

A functional endocannabinoid system is present in several mammalian organs and tissues. The endogenous cannabinoid anandamide (AEA) is a bioactive lipid neurotransmitter that is present in a variety of tissues and has multiple functions. Recently, this cannabinoid system was reported to play important roles in osteoblastic and osteoclastic cells. Human periodontal ligament (hPDL) cells modulate alveolar bone remodeling by producing cytokines when stimulated by many factors. The aim of this study was to investigate the AEA level in periodontal regions and the osteogenic effect of AEA on hPDL cells. The levels of AEA in the gingival crevicular fluid (GCF) of periodontitis patients were measured using liquid chromatography/mass spectrometry (LC/MS). Expressions of cannabinoid receptor mRNA were detected by RT-PCR in hPDL cells and expression of the transient receptor potential cation channel subfamily V member 1 (TRPV1) was observed by confocal laser scanning microscope (CLSM). IL-11 production from hPDL cells was measured using an ELISA, with or without AEA in the presence or absence of capsazepine, a selective TRPV1 antagonist AEA secreted into GCF was detected, but there was no correlation between the probing pocket depth (PPD) and AEA level. TRPV1 mRNA was detected in hPDL cells and the TRPV1 expression was observed by CLSM. IL-11 production from hPDL cells was significantly enhanced by AEA stimulation and this IL-11 production was suppressed by capsazepine. Our findings indicate that this endogenous cannabinoid system has a possible role in bone metabolism in periodontitis through TRPV1.

Cannabinoid 1 receptor promotes cardiac dysfunction, oxidative stress, inflammation, and fibrosis in diabetic cardiomyopathy

Endocannabinoids and cannabinoid 1 (CB(1)) receptors have been implicated in cardiac dysfunction, inflammation, and cell death associated with various forms of shock, heart failure, and atherosclerosis, in addition to their recognized role in the development of various cardiovascular risk factors in obesity/metabolic syndrome and diabetes. In this study, we explored the role of CB(1) receptors in myocardial dysfunction, inflammation, oxidative/nitrative stress, cell death, and interrelated signaling pathways, using a mouse model of type 1 diabetic cardiomyopathy. Diabetic cardiomyopathy was characterized by increased myocardial endocannabinoid anandamide levels, oxidative/nitrative stress, activation of p38/Jun NH(2)-terminal kinase (JNK) mitogen-activated protein kinases (MAPKs), enhanced inflammation (tumor necrosis factor-α, interleukin-1β, cyclooxygenase 2, intracellular adhesion molecule 1, and vascular cell adhesion molecule 1), increased expression of CB(1), advanced glycation end product (AGE) and angiotensin II type 1 receptors (receptor for advanced glycation end product [RAGE], angiotensin II receptor type 1 [AT(1)R]), p47(phox) NADPH oxidase subunit, β-myosin heavy chain isozyme switch, accumulation of AGE, fibrosis, and decreased expression of sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA2a). Pharmacological inhibition or genetic deletion of CB(1) receptors attenuated the diabetes-induced cardiac dysfunction and the above-mentioned pathological alterations. Activation of CB(1) receptors by endocannabinoids may play an important role in the pathogenesis of diabetic cardiomyopathy by facilitating MAPK activation, AT(1)R expression/signaling, AGE accumulation, oxidative/nitrative stress, inflammation, and fibrosis. Conversely, CB(1) receptor inhibition may be beneficial in the treatment of diabetic cardiovascular complications.

Chromatographic methods for metabolite profiling of virus- and phytoplasma-infected plants of Echinacea purpurea

This study was focused on the effects of virus and phytoplasma infections on the production of Echinacea purpurea (L.) Moench secondary metabolites, such as caffeic acid derivatives, alkamides, and essential oil. The identification of caffeic acid derivatives and alkamides was carried out by means of high-performance liquid chromatography-diode array detection (HPLC-DAD), HPLC-electrospray ionization-mass spectrometry (ESI-MS), and MS(2). Quantitative analysis of these compounds was carried out using HPLC-DAD. The results indicated that the presence of the two pathogens significantly decreases (P < 0.05) the content of cichoric acid, the main caffeic acid derivative. Regarding the main alkamide, dodeca-2E,4E,8Z,10E/Z-tetraenoic acid isobutylamide, a significant decrease (P < 0.05) in the content of this secondary metabolite was observed in virus-infected plants in comparison with healthy plants, while in the phytoplasma-infected sample the variation of this secondary metabolite was not appreciable. The % relative area of the E/Z isomers of this alkamide was also found to change in infected samples. The gas chromatography (GC) and GC-MS analysis of E. purpurea essential oil enabled the identification of 30 compounds. The main significant differences (P < 0.05) in the semiquantitative composition were observed for three components: limonene, cis-verbenol, and verbenone. The results indicate that the presence of virus and phytoplasma has an appreciable influence on the content of E. purpurea secondary metabolites, which is an important issue in defining the commercial quality, market value, and therapeutic efficacy of this herbal drug.

[HPLC determination of four components in Tibetan medicine Dangzuo of different Tibetan regions]

OBJECTIVE

To develop an HPLC method for determination of gallic acid, hydroxysafflor yellow A, cinnamic aldehyde and piperine in Tibetan medicine Dangzuo, and to compare the content of four active components in Dangzuo of different Tibetan regions.

METHOD

The separation was carried out on a Waters XTerra RP-C18 column ( 4.6 mm x 250 mm, 5 microm). The mobile phases were methanol and water, all contained 0.1% glacial acetic acid, for gradient elution. The gradient program was as follows: 0-22.5 min, methanol was changed from 5% to 50%; 22.5-40 min, changed to 80% 80:20. The flow rate was 1.0 mL x min(-1). The detection wavelength was 270 nm. The reference wavelength was 500 nm.

RESULT

The linear ranges of gallic acid, hydroxysafflor yellow A, cinnamic aldehyde and piperine were 0.040-0.640 microg (r = 0.999 8), 0.090-1.440 microg (r = 0.999 9), 0.031-0.500 microg (r = 0.999 9 ) and 0.092-41.477 microg (r = 0.998 9), respectively. The average recoveries (n = 6) were 97.42% (RSD 1.9%), 97.55% (RSD 2.9%), 98.69% (RSD 0.96%) and 96.72% (RSD 4.0%), respectively. The content ranges of gallic acid, hydroxysafflor yellow A, cinnamic aldehyde and piperine in Dangzuo samples of different Tibetan regions were 0.11341.69 mg x g(-1), 0.889-1.51 mg x g(-1), 0.000-40.606 mg x g(-1) and 1.96-2.73 mg x g(-1), respectively.

CONCLUSION

The method is a simple and effective for quality control of Tibetan medicine Dangzuo.

Purification of alkylamides from Echinacea angustifolia (DC.) Hell. Roots by high-speed countercurrent chromatography

High-speed countercurrent chromatography (HSCCC) was used for the separation of alkylamides from the roots of Echinacea angustifolia (DC.) Hell. For this purpose, the alkylamides were extracted with hexane and subjected to semipreparative HSCCC using a two-phase solvent system consisting of n-hexane, ethyl acetate, methanol, and water (4:1:2:1). The lower aqueous phase was used as the mobile phase at a flow rate of 3 mL/min and a rotary speed of 1000 rpm. This procedure led to the isolation of four pure alkylamides, that is, dodeca-2E,4E,8Z,10E/Z-tetraenoic acid isobutylamide (38.9 mg, 97% purity), dodeca-2E,4E,8Z-trienoic acid isobutylamide (4.4 mg, 92% purity), dodeca-2E,4E-dienoic acid isobutylamide (3.2 mg, 99% purity), and dodeca-2E,4E-dienoic acid 2-methylbutylamide (0.3 mg, 92% purity). The identity and purity of the isolated alkylamides were confirmed by LC-ESI-MS and (1)H NMR and (13)C NMR data. To the best of the authors' knowledge, this is the first report of dodeca-2E,4E-dienoic acid 2-methylbutylamide in E. angustifolia roots.

Anandamide and AM251, via water, modulate food intake at central and peripheral level in fish

The endocannabinoid system is a major regulator of food intake in many animal species. Studies conducted so far have mostly focused on mammals, and, therefore, in this study, the role of the endocannabinoid system in food intake in the sea bream Sparus aurata was investigated. The effect of different doses of the endocannabinoid anandamide (AEA), administered via water, was evaluated after different exposure times (30, 60 and 120 min) at both physiological and molecular levels. The results obtained indicate that fish exposed to AEA via water present approximately 1000-fold higher levels of AEA in both the brain and liver, which correlated with a significant increase in food intake and with the elevation of cannabinoid receptor 1 (CB(1)) and neuropeptide Y (NPY) mRNA levels in the brain. A peripheral effect of AEA was also observed, since a time-dependent increase in hepatic CB(1) mRNA and protein levels was detected. These effects were attenuated by the administration, again via water, of a selective cannabinoid CB(1) receptor antagonist (AM251). These findings indicate that the endocannabinoid AEA, at doses that stimulate food intake in fish, concomitantly stimulates the expression of the orexigenic peptide NPY as well that of its own receptor, thereby potentially enhancing its effect on food consumption. In agreement with a role of AEA in food intake in S. aurata, we found increased brain levels of both this and the other endocannabinoid, 2-arachidonoylglycerol (2-AG), following food deprivation.

Transdermal behaviour of the N-alkylamide spilanthol (affinin) from Spilanthes acmella (Compositae) extracts

AIM OF THE STUDY

N-Alkylamides are a large group of bioactive molecules found in several plants from the genera Echinacea, Xanthoxylum and Spilanthes. Extracts and formulations derived from these plants are not only orally used, but also applied on the skin as well. However, there is currently no specific information available about the intrinsic local pharmacokinetics of N-alkylamides after topical application on human skin, questioning the role of this mode of administration. The present study investigates the transdermal behaviour of spilanthol, a prominent N-alkylamide.

MATERIALS AND METHODS

Two pharmaceutically accepted dose solutions (ethanol and propylene glycol based aqueous donor vehicles), combined with three different receptor fluids (PBS, PBS+0.5% HPbetaCD, EtOH/H(2)O (30:70, v/v)), were applied on split-thickness human skin in a Franz diffusion cell (FDC) system. Fundamental permeation characteristics of spilanthol in a solvent-independent way (100% aqueous dose solution) were also obtained using an extrapolation approach with different organic solvent/H(2)O ratios.

RESULTS AND CONCLUSIONS

We demonstrated for the first time that spilanthol permeates the skin. The following aqueous-extrapolated primary transdermal parameters were obtained (mean+/-SEM): K(p,aq)=3.31 (+/-0.29)x10(-3)cm/h, D(m,aq)=1.86 (+/-0.09)x10(-4)cm(2)/h and K(m,aq)=7.28 (+/-1.59)x10(-1). Partitioning (K(m)) was strongly dependent on the donor solution composition, while diffusion (D(m)) was mainly influenced by the receptor fluid composition.

Stability-indicating reversed-phase liquid chromatographic methods for the determination of aconitine and piperine in a polyherbal formulation

Simple and rapid stability-indicating HPLC methods were developed for the individual analysis of aconitine (ACN) and piperine (PIN) in Mahamrutynjaya rasa, an herbal dosage form containing Aconitum ferox, Piper nigrum, and Piper longum in combination. Separation of the ACN from its major and minor degradation products was successfully achieved on a reversed-phase C18 column (250 x 4.6 mm id, 5 microm particle size), with isocratic elution using a mixture of acetonitrile-KH2PO4 buffer (10 mM, pH 8 +/- 0.1; 50 + 50, v/v) at flow rate of 0.7 mL/min with UV detection at 227 nm. PIN separation was performed on a reversed-phase C18 column (250 x 4.6 mm id, 5 microm particle size), with isocratic elution in acetonitrile-KH2PO4 buffer (10 mM, pH 7 +/- 0.1; 35 + 65, v/v) at a flow rate of 1 mL/min with UV detection at 343 nm. The methods were validated with respect to linearity, precision, accuracy, specificity, system suitability, and robustness. The responses were linear in the drug concentration range of 10-100 microg/mL for both ACN and PIN. The percent recoveries of both the markers from a mixture of degradation products were in the range between 98-101%. The utility of the procedures was verified by their application to marketed formulations that were subjected to accelerated degradation studies. The methods could distinctly separate the drug and degradation products. The products formed in the marketed tablets were similar to those formed in the laboratory during stress studies.

Localisation and function of the endocannabinoid system in the human ovary

BACKGROUND

Although anandamide (AEA) had been measured in human follicular fluid and is suggested to play a role in ovarian follicle and oocyte maturity, its exact source and role in the human ovary remains unclear.

METHODS AND FINDINGS

Immunohistochemical examination of normal human ovaries indicated that the endocannabinoid system was present and widely expressed in the ovarian medulla and cortex with more intense cannabinoid receptor 2 (CB2) than CB1 immunoreactivity in the granulosa cells of primordial, primary, secondary, tertiary follicles, corpus luteum and corpus albicans. The enzymes, fatty acid amide hydrolase (FAAH) and N-acyclphosphatidylethanolamine-phospholipase D (NAPE-PLD), were only found in growing secondary and tertiary follicles and corpora lutea and albicantes. The follicular fluid (FF) AEA concentrations of 260 FF samples, taken from 37 infertile women undergoing controlled ovarian hyperstimulation for in vitro fertilisation and intracytoplasmic sperm injection with embryo transfer, were correlated with ovarian follicle size (P = 0.03). Significantly higher FF AEA concentrations were also observed in mature follicles (1.43+/-0.04 nM; mean+/-SEM) compared to immature follicles (1.26+/-0.06 nM), P = 0.0142 and from follicles containing morphologically assessed mature oocytes (1.56+/-0.11 nM) compared to that containing immature oocytes (0.99+/-0.09 nM), P = 0.0011. ROC analysis indicated that a FF AEA level of 1.09 nM could discriminate between mature and immature oocytes with 72.2% sensitivity and 77.14% specificity, whilst plasma AEA levels and FF AEA levels on oocyte retrieval day were not significantly different (P = 0.23).

CONCLUSIONS

These data suggest that AEA is produced in the ovary, is under hormonal control and plays a role in folliculogenesis, preovulatory follicle maturation, oocyte maturity and ovulation.

A solid-phase method for the extraction and measurement of anandamide from multiple human biomatrices

N-Arachidonoylethanolamine (AEA, anandamide) was the first endocannabinoid to be identified and has since become associated with the mediation of several physiological functions and disease states. AEA has been isolated from numerous tissues and biofluids, in the low nanomolar range, using lipid extraction techniques with organic solvents. These techniques require the drying down of relatively large volumes of solvents, making them unsuitable for high-throughput analysis. Here we describe a solid-phase extraction (SPE) method for the investigation of AEA concentrations in human plasma, serum, milk, urine, amniotic fluid, peritoneal fluid, saliva, follicular fluid, and fluid from an ovarian cyst. AEA was detected in serum and plasma from blood isolated from 20 adult women (means+/-standard deviations: 0.68+/-0.29 and 0.64+/-0.28 nM, respectively), from pregnant women at term (1.37+/-0.42 nM), and from umbilical vein (1.26+/-0.33 nM) and umbilical artery (1.14+/-0.35nM), in milk (0.12+/-0.05 nM) and from amniotic (0.03+/-0.02 nM), peritoneal (0.93+/-0.27 nM), follicular (1.17+/-0.51 nM), and ovarian cyst (0.32+/-0.01 nM) fluids. AEA was undetectable in saliva and urine. The 60% AEA extraction efficiency achieved with SPE from plasma was superior to the 19% efficiency achieved using the existing organic solvent extraction method. Limits of quantification and detection for AEA were also improved dramatically using SPE (8 and 4 fmol/ml) compared with organic extraction (25 and 18.75 fmol/ml plasma). These improvements allow the use of smaller plasma samples with SPE. Intra- and interday variability were comparable, and the mean AEA concentration of pooled plasma samples (1.18 nM, n=15) was identical with the two techniques. Similarly, when 56 plasma samples from laboring and nonlaboring women were analyzed using both techniques, no extraction method-dependent differences were observed. Consequently, we provide evidence for a robust SPE technique for the extraction of AEA from biomatrices to replace the existing liquid extraction methods, with the SPE technique being superior in terms of speed, extraction efficiency, and sample size required.

Physicochemical and microbiological qualities of steamed and irradiated ground black pepper (Piper nigrum L.)

The effects of steam and irradiation treatments on the physicochemical properties (moisture content, pH, extractable yield, reducing sugar, soluble pigment, antioxidant activity, piperine, Hunter's color, and sensory attributes) and microbiological quality (total aerobic bacteria, coliforms, and yeasts and molds) of ground black pepper stored at refrigerated and room temperatures for 6 months were compared and evaluated. Irradiation resulted in a higher microbial reduction in pepper, with minimal effects on the proximate composition, functional components, color, and sensory attributes of the spice. Steamed peppers appeared darker, and a considerable decrease in the piperine content was observed after treatment and storage. This study illustrates that irradiation is a better decontamination method than steam treatment in eliminating microorganisms without apparently affecting the quality of the powdered spice. Storage at 4 degrees C enhanced the microbial quality and minimized the loss of piperine content in ground black peppers.

Analysis by HPLC and LC/MS of pungent piperamides in commercial black, white, green, and red whole and ground peppercorns

Pepper plants accumulate pungent bioactive alkaloids called piperamides. To facilitate studies in this area, high-performance liquid chromatography (HPLC) and liquid chromatography/mass spectrometry methods were developed and used to measure the following piperamides in 10 commercial whole (peppercorns) and in 10 ground, black, white, green, and red peppers: piperanine, piperdardine, piperine, piperlonguminine, and piperettine. Structural identification of individual compounds in extracts was performed by associating the HPLC peak of each compound with the corresponding mass spectrum. The piperanine content of the peppers (in mg/g piperine equivalents) ranged from 0.3 for the ground white pepper to 1.4 in black peppercorns. The corresponding range for piperdardine was from 0.0 for seven samples to 1.8 in black peppercorns; for four isomeric piperines, from 0.7 for red to 129 in green peppercorns; for piperlonguminine, from 0.0 in red peppercorns to 1.0 in black peppercorns; and for piperyline, from 0.9 in ground black pepper to 5.9 for red peppercorn. Four well-separated stereoisomeric forms of piperettine with the same molecular weight were present in 19 peppers. The sums of the piperamides ranged from 6.6 for red to 153 for green peppercorns. In contrast to large differences in absolute concentrations among the peppers, the ratios of piperines to total piperamide were quite narrow, ranging from 0.76 for black to 0.90 for white peppercorns, with an average value of 0.84 +/- 0.04 ( n = 19). Thus, on average, the total piperamide content of the peppers consists of 84% piperines and 16% other piperamides. These results demonstrate the utility of the described extraction and analytical methods used to determine the wide-ranging individual and total piperamide contents of widely consumed peppers.

Simultaneous determination of cinnamaldehyde, eugenol and piperine by HPTLC densitometric method

An HPTLC densitometric method for the simultaneous determination of cinnamaldehyde and eugenol as well as trace amounts of piperine in pepper-contaminated cinnamon was developed. The applicability of the method was tested with cinnamon bark powder adulterated with pepper powder, cinnamon oil, clove powder, clove oil and a commercial preparation containing cinnamaldehyde and eugenol. The method was validated for specificity, precision, accuracy and robustness. The method was found to be precise for different concentrations of cinnamaldehyde, eugenol and piperine. The accuracy of the method was checked by conducting a recovery study at three different levels. The linearity was found to be in the ranges 52.54-735.56, 533.2-8531.2 and 50-300 ng/spot, respectively, with correlation coefficients of 0.9985 +/- 0.04, 0.9982 +/- 0.06 and 0.9937 +/- 0.11 for cinnamaldehyde, eugenol and piperine.

Kinetics of light-induced cis-trans isomerization of four piperines and their levels in ground black peppers as determined by HPLC and LC/MS

The pungent compounds piperine and isomers thereof, secondary metabolites present in black and white pepper fruit, undergo light-induced isomerizations. To facilitate studies in this area, an HPLC method has been developed for analysis and isolation of the following four possible piperine-derived photoinduced isomers: piperine, isopiperine, chavicine, and isochavicine. The limits of detection (LOD) estimated from calibration plots were approximately 15-30 ng for each isomer. Reproducibilities of the analyses were excellent, and recoveries of spiked samples were as follows (average +/- SD; n = 3): chavicine, 98.4 +/- 2.1%; isopiperine, 96.2 +/- 3.2%; piperine, 104 +/- 3.8%; isochavicine, 98.9 +/- 3.0%. To determine the kinetics of these isomerizations, fluorescent light, sunlight, and UV radiation at 254 nm was used to induce cis-trans geometric isomerization as a function of light intensities and time of exposure determined with the aid of high-performance liquid chromatography (HPLC) and liquid chromatography with diode array UV detection-mass spectrometry (LC-DAD/MS). HPLC was also used to determine the distribution of the isomers in four commercial ground black pepper products used as spices in culinary practice. Isomerization increased with light intensities and time of exposure and leveled off at the so-called photostationary phases. The piperine levels of the four products were quite similar, ranging (in wt %) from 10.17 to 11.68. The amounts of the other three isomers ranged from 0.01 to 0.07 of the total for chavicine; from 0.15 to 0.23 for isopiperine; and from 0.37 to 0.42 for isochavicine. The results establish the utility of the HPLC method for simultaneous analysis of the four isomers both in pure form and in black pepper extracts. The dietary significance of the results is discussed.

Inhibitory effect of ethanol extract of Piper longum L. on rabbit platelet aggregation through antagonizing thromboxane A2 receptor

Piper longum L. has been used as a crude drug for the treatment of disorders of poor peripheral blood circulation in Asia. However, the detailed mechanism of its action has not been clarified as yet. In the present study, we examined the effects of several extracts of Piper longum L. on rabbit platelet function. Thromboxane A(2) receptor agonist U46619 caused rabbit platelet aggregation, which was potently inhibited by the ethanol or butanol extract of Piper longum L. The ethanol extract inhibited U46619-induced platelet aggregation in a concentration-dependent manner, but only weakly inhibited that induced by thrombin. The maximum response to U46619 was reduced by 100% ethanol extract concentration dependently, suggesting that the inhibitory mode of U46619-induced platelet aggregation by the ethanol extract was non-competitive. The extract also inhibited U46619-induced phosphoinositide hydrolysis with a similar concentration dependency to the platelet aggregation. Furthermore, the extract inhibited binding of [(3)H]SQ29548 to thromboxane A(2) receptor in intact platelets in a concentration-dependent manner. These results suggest that Piper longum L. contains a constituent(s) that inhibits platelet aggregation as a non-competitive thromboxane A(2) receptor antagonist.

Quantitative method for the profiling of the endocannabinoid metabolome by LC-atmospheric pressure chemical ionization-MS

The endocannabinoid system's biological significance continues to grow as novel endocannabinoid metabolites are discovered. Accordingly, a myopic view of the system that focuses solely on one or two endocannabinoids, such as anandamide or 2-arachidonoyl glycerol, is insufficient to describe the biological responses to perturbations of the system. Rather, the endocannabinoid metabolome as a whole must be analyzed. The work described here is based on liquid chromatography coupled with atmospheric pressure chemical ionization mass spectrometry. This method has been validated to quantify, in a single chromatographic run, the levels of 15 known or suspected metabolites of the endocannabinoid system in the rat brain and is applicable to other biological matrixes. We have obtained an endocannabinoid profile specifically for the frontal cortex of the rat brain and have determined anandamide level differences following the administration of the fatty acid amide hydrolase inhibitor AM374.

Short-term exposure to alcohol in rats affects brain levels of anandamide, other N-acylethanolamines and 2-arachidonoyl-glycerol

Chronic alcohol exposure leads to significant changes in the levels of endocannabinoids and their receptors in the brains of humans and laboratory animals, as well as in cultured neuronal cells. However, little is known about the effects of short-term periods of alcohol exposure. In the present study, we examined the changes in endocannabinoid levels (anandamide and 2-arachidonoylglycerol), as well as four additional N-acylethanolamines, in four brain regions of rats exposed to alcohol through the liquid diet for a period of 24h. The levels of N-acylethanolamines were diminished 24h after the onset of alcohol exposure. This was particularly evident for anandamide in the hypothalamus, amygdala and caudate-putamen, for N-palmitoylethanolamine in the caudate-putamen, for N-oleoylethanolamine in the hypothalamus, caudate-putamen and prefrontal cortex, and for N-stearoylethanolamine in the amygdala. The only exception was N-linoleoylethanolamine for which the levels increased in the amygdala after the exposure to alcohol. The levels of the other major endocannabinoid, 2-arachidonoylglycerol, were also reduced with marked effects in the prefrontal cortex. These results support the notion that short-term alcohol exposure reduces endocannabinoid levels in the brain accompanied by a reduction in several related N-acylethanolamines.

Opposing control of cannabinoid receptor stimulation on amyloid-beta-induced reactive gliosis: in vitro and in vivo evidence

Beside cytotoxic mechanisms impacting on neurons, amyloid beta (A beta)-induced astroglial activation is operative in Alzheimer's disease brain, suggesting that persistent inflammatory response may have a role in the illness and that positive results may be achieved by curbing the astroglial reaction. Because the role of the endocannabinoid system could represent a promising field of research, the present study conducted in vitro and in vivo experiments to assess this system. C6 rat astroglioma cells were challenged with 1 microg/ml A beta 1-42 in the presence or absence of selective agonists and antagonists of cannabinoid (CB)1 and CB2 receptors. Furthermore, rats were inoculated into the frontal cortex with 30 ng of A beta 1-42 and were i.p. administered with 5 mg/kg of the same substances. Immunohistochemical and biochemical findings revealed that selective agonism at CB1 and antagonism at CB2 receptors was able to blunt A beta-induced reactive astrogliosis with subsequent overexpression of glial fibrillary acidic protein and S100B protein. Moreover, A beta provoked down-regulation of CB1 receptors together with a reduction of anandamide concentration, whereas CB2 receptors were up-regulated and 2-arachidonoyl glycerol concentration was increased. Finally, to our knowledge, the current study is the first showing that interactions at cannabinoid receptors result in a dual regulation of A beta-induced reactive astrogliosis. The data support the assumption that compounds able to selectively block CB2 receptors may have therapeutic potential in controlling A beta-related pathology, due to their beneficial effects devoid of psychotropic consequences.

Endocannabinoid enhancement protects against kainic acid-induced seizures and associated brain damage

Endocannabinoids are released in response to pathogenic insults, and inhibitors of endocannabinoid inactivation enhance such on-demand responses that promote cellular protection. Here, AM374 (palmitylsulfonyl fluoride), an irreversible inhibitor of fatty acid amide hydrolase (FAAH), was injected i.p. into rats to test for endocannabinoid enhancement. AM374 caused a prolonged elevation of anandamide levels in several brain regions, including the hippocampus, and resulted in rapid activation of the extracellular signal regulated-kinase/mitogen-activated protein kinase pathway that has been linked to survival. To evaluate the neuroprotective nature of the FAAH inhibitor, we tested AM374 in a seizure model involving rats insulted with kainic acid (KA). AM374 was injected immediately after KA administration, and seizure scores were significantly reduced throughout a 4-h observation period. The KA-induced seizures were associated with calpain-mediated cytoskeletal breakdown, reductions in synaptic markers, and loss of CA1 hippocampal neurons. FAAH inhibition protected against the excitotoxic damage and neuronal loss assessed 48 h postinsult. AM374 also preserved pre- and postsynaptic markers to levels comparable with those found in noninsulted animals, and the synaptic marker preservation strongly correlated with reduced seizure scores. With regard to behavioral deficits in the excitotoxic rats, AM374 produced nearly complete functional protection, significantly improving balance and coordination across different behavioral paradigms. These data indicate that AM374 crosses the blood-brain barrier, enhances endocannabinoid responses in key neuronal circuitries, and protects the brain against excitotoxic damage.

Cannabinoid-2 receptor mediates protection against hepatic ischemia/reperfusion injury

Hepatic ischemia-reperfusion (I/R) injury continues to be a fatal complication that can follow liver surgery or transplantation. We have investigated the involvement of the endocannabinoid system in hepatic I/R injury using an in vivo mouse model. Here we report that I/R triggers several-fold increases in the hepatic levels of the endocannabinoids anandamide and 2-arachidonoylglycerol, which originate from hepatocytes, Kupffer, and endothelial cells. The I/R-induced increased tissue endocannabinoid levels positively correlate with the degree of hepatic damage and serum TNF-alpha, MIP-1alpha, and MIP-2 levels. Furthermore, a brief exposure of hepatocytes to various oxidants (H2O2 and peroxynitrite) or inflammatory stimuli (endotoxin and TNF-alpha) also increases endocannabinoid levels. Activation of CB2 cannabinoid receptors by JWH133 protects against I/R damage by decreasing inflammatory cell infiltration, tissue and serum TNF-alpha, MIP-1alpha and MIP-2 levels, tissue lipid peroxidation, and expression of adhesion molecule ICAM-1 in vivo. JWH133 also attenuates the TNF-alpha-induced ICAM-1 and VCAM-1 expression in human liver sinusoidal endothelial cells (HLSECs) and the adhesion of human neutrophils to HLSECs in vitro. Consistent with the protective role of CB2 receptor activation, CB2-/- mice develop increased I/R-induced tissue damage and proinflammatory phenotype. These findings suggest that oxidative/nitrosative stress and inflammatory stimuli may trigger endocannabinoid production, and indicate that targeting CB2 cannabinoid receptors may represent a novel protective strategy against I/R injury. We also demonstrate that CB2-/- mice have a normal hemodynamic profile.

Changes in endocannabinoid and palmitoylethanolamide levels in eye tissues of patients with diabetic retinopathy and age-related macular degeneration

Cannabinoid receptors and the endocannabinoids (anandamide (N-arachidonoylethanolamine--AEA) and 2-arachidonoylglycerol (2-AG)), as well as the AEA congener, palmitoylethanolamide (PEA), are involved in ocular physiology. We measured endocannabinoid and PEA levels by isotope-dilution liquid chromatography-mass spectrometric analysis in post-mortem eye tissues of patients with diabetic retinopathy (DR) or age-related macular degeneration (AMD). In eyes with DR, significantly enhanced levels of AEA were found in the retina ( approximately 1.8-fold), ciliary body ( approximately 1.5-fold) and, to a lesser extent, cornea ( approximately 1.3-fold). Surprisingly, 2-AG levels were significantly higher ( approximately 3-fold) only in the iris, whereas PEA levels only slightly increased ( approximately 1.3-fold) in the ciliary body. In eyes with AMD, significantly enhanced levels of AEA were found in the choroid ( approximately 1.3-fold), ciliary body ( approximately 1.4-fold) and cornea ( approximately 1.4-fold), whereas in the retina only a trend towards an increase ( approximately 1.5-fold) was observed. The tissue- and disease-selective nature of the changes observed suggests that the compounds analyzed here may play different roles in the control of eye function under different pathological conditions.

Quantitative profiling of endocannabinoids and related compounds in rat brain using liquid chromatography-tandem electrospray ionization mass spectrometry

A sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method is described for the simultaneous identification and quantification of eight endocannabinoid (EC) or related "entourage" compounds in rat brain tissue. Analytes were extracted and purified from rat brain tissue using an ethyl acetate/hexane solvent extraction, followed by a solid phase extraction (SPE) protocol. Chromatographic separation was achieved using a gradient elution, with a mobile phase of acetonitrile, formic acid, and ammonium acetate, at pH 3.6. A Thermo Hypersil C8 HyPurity Advance column (100x2.1 mm i.d., 3 microm) was used with a flow rate of 0.3 ml/min). Anandamide (AEA), 2-arachidonyl glycerol (2-AG), 2-arachidonylglyceryl ether (noladin ether), O-arachidonyl ethanolamide (virodhamine), 2-linoleoyl glycerol (2-LG), arachidonyl glycine, oleoyl ethanolamide (OEA), and palmitoyl ethanolamide (PEA) were quantified by positive ion tandem electrospray ionization mass spectrometry. Internal standards were deuterated AEA, deuterated 2-AG, and heptadecanoyl ethanolamide (HEA). Linearity was proven over the range of 25 fmol to 250 pmol, with a limit of detection of 25 fmol on column for all analytes except 2-AG, noladin ether, and 2-LG (250 fmol). This corresponded to a limit of quantification in biological tissue of 10 pmol/g for all analytes except 2-AG (100 pmol/g). Intra- and interday precision in biological tissue was routinely approximately 20% or lower, and accuracy was between 65% and 155%. This method was used to quantitatively profile regional differences in nine discrete rat brain regions for AEA, 2-AG, 2-LG, OEA, PEA, noladin ether, virodhamine, and arachidonyl glycine.

Pharmacological Characterization of Endocannabinoid Transport and Fatty Acid Amide Hydrolase Inhibitors

: 1. The mechanism of anandamide uptake and disposal has been an issue of considerable debate in the cannabinoid field. Several compounds have been reported to inhibit anandamide uptake or fatty acid amide hydrolase (FAAH; the primary catabolic enzyme of anandamide) activity with varying degrees of potency and selectivity. We recently reported the first evidence of a binding site involved in the uptake of endocannabinoids that is independent from FAAH. There are no direct comparisons of purported selective inhibitory compounds in common assay conditions measuring anandamide uptake, FAAH activity and binding activity. 2. A subset of compounds reported in the literature were tested in our laboratory under common assay conditions to measure their ability to (a) inhibit [(14)C]-anandamide uptake in cells containing (RBL-2H3) or cells lacking (HeLa) FAAH, (b) inhibit purified FAAH hydrolytic activity, and (c) inhibit binding to a putative binding site involved in endocannabinoid transport in both RBL and HeLa cell membranes. 3. Under these conditions, nearly all compounds tested inhibited (a) uptake of [(14)C]-anandamide, (b) enzyme activity in purified FAAH preparations, and (c) radioligand binding of [(3)H]-LY2183240 in RBL and HeLa plasma membrane preparations. General rank order potency was preserved within the three assays. However, concentration response curves were right-shifted for functional [(14)C]-anandamide uptake in HeLa (FAAH(-/-)) cells. 4. A more direct comparison of multiple inhibitors could be made in these three assay systems performed in the same laboratory, revealing more information about the selectivity of these compounds and the relationship between the putative endocannabinoid transport protein and FAAH. At least two separate proteins appear to be involved in uptake and degradation of anandamide. The most potent inhibitory compounds were right-shifted when transport was measured in HeLa (FAAH(-/-)) cells suggesting a requirement for a direct interaction with the FAAH protein to maintain high affinity binding of anandamide or inhibitors to the putative anandamide transport protein.

Studies on High-energy Collision-induced Dissociation of Endogenous Cannabinoids: 2-Arachidonoylglycerol and N-Arachidonoylethanolamide in FAB-Mass Spectrometry

Analysis of 2-arachidonoylglycerol (2-AG) and N-arachidonoylethanolamide (anandamide) via alkali or alkaline earth metal-adduct high-energy collision-induced dissociation (CID) in fast-atom bombardment (FAB) ionization-mass spectrometry (MS) is described. The CID-MS/MS of the [2-AG+Li](+) or [2-AG+Na](+) ion undergoes charge-remote fragmentation (CRF), which is useful for the determination of the double-bond positions in the hydrocarbon chain, while the CID-MS/MS of the [2-AG-H+Cat](+) (Cat = Mg(2+), Ca(2+), Ba(2+)) ion provides an abundant fragment ion of the cationized arachidonic acid species, which is derived from cleaving the ester bond via a McLafferty-type rearrangement in addition to structurally informative CRF ions in small amounts. On the other hand, the CID-MS/MS spectra of anandamide cationized with both alkali metal (Li(+) or Na(+)) and alkaline earth metal (Mg(2+), Ca(2+), or Ba(2+)) show CRF patterns: the spectra obtained in lithium or sodium adduct are more clearly visible than those in magnesium, calcium, or barium adduct. The McLafferty rearrangement is not observed with metal-adduct anandamide. The characteristics in each mass spectrum are useful for the detection of these endogenous ligands. m-Nitrobenzyl alcohol (m-NBA) is the most suitable matrix. A lithium-adduct [2-AG+Li](+) or [anandamide+Li](+) ion is observed to be the most abundant in each mass spectrum, since the affinity of lithium for m-NBA is lower than that for other matrices examined.

Bioavailability of Echinacea constituents: Caco-2 monolayers and pharmacokinetics of the alkylamides and caffeic acid conjugates

Many studies have been done over the years to assess the effectiveness of Echinacea as an immunomodulator. We have assessed the potential bioavailability of alkylamides and caffeic acid conjugates using Caco-2 monolayers and compared it to their actual bioavailability in a Phase I clinical trial. The caffeic acid conjugates permeated poorly through the Caco-2 monolayers. Alkylamides were found to diffuse rapidly through Caco-2 monolayers. Differences in diffusion rates for each alkylamide correlated to structural variations, with saturation and N-terminal methylation contributing to decreases in diffusion rates. Alkylamide diffusion is not affected by the presence of other constituents and the results for a synthetic alkylamide were in line with those for alkylamides found in an ethanolic Echinacea preparation. We examined plasma from healthy volunteers for 12 hours after ingestion of Echinacea tablets manufactured from an ethanolic liquid extract. Caffeic acid conjugates could not be identified in any plasma sample at any time after tablet ingestion. Alkylamides were detected in plasma 20 minutes after tablet ingestion and for each alkylamide, pharmacokinetic profiles were devised. The data are consistent with the dosing regimen of one tablet three times daily and supports their  usage as the primary markers for quality Echinacea preparations.