Nucleoside and N-acetyldopamine derivatives from the insect Aspongopus chinensis.

Two new nucleoside derivatives, named asponguanosines A and B (1 and 2), three new N-acetyldopamine analogues, aspongamides C-E (3-5), one new sesquiterpene, aspongnoid D (6), and three known compounds were isolated from the medicinal insect Aspongopus chinensis. Their structures including absolute configurations were assigned by using spectroscopic methods and ECD and 13C NMR calculations. Biological activities of compounds 3-7 towards human cancer cells, COX-2, ROCK1, and JAK3 were evaluated.

Quinoxaline-, dopamine-, and amino acid-derived metabolites from the edible insect Protaetia brevitarsis seulensis.

Edible insects have been reported to produce metabolites showing various pharmacological activities, recently emerging as rich sources of health functional food. In particular, the larvae of Protaetia brevitarsis seulensis (Kolbe) have been used as traditional Korean medicines for treating diverse diseases, such as breast cancer, inflammatory disease, hepatic cancer, liver cirrhosis, and hepatitis. However, only few chemical investigations were reported on the insect larvae. Therefore, the aim of this study was to discover and identify biologically active chemical components of the larvae of P. brevitarsis seulensis. As a result, a quinoxaline-derived alkaloid (1) was isolated, which was not reported previously from natural sources. In addition, other related compounds (2, 4-10, 15, 16) were also encountered for the first time from the larvae. The structures of all the isolated compounds were established mainly by analysis of HRESIMS, NMR, and electronic circular dichroism data. Compound 5 exhibited inhibition of tyrosinase with IC50 value of 44.8 µM.

Immunomodulatory N-acyl Dopamine Glycosides from the Icelandic Marine Sponge Myxilla incrustans Collected at a Hydrothermal Vent Site.

A chemical investigation of the sponge (Porifera) Myxilla incrustans collected from the unique submarine hydrothermal vent site Strytan, North of Iceland, revealed a novel family of closely related N-acyl dopamine glycosides. Three new compounds, myxillin A (1), B (2) and C (3), were isolated and structurally elucidated using several analytical techniques, such as HR-MS, 1D and 2D NMR spectroscopy. Myxillin A (1) and B (2)were shown to be structurally similar, composed of a dopamine moiety, but differ in the acyl chain length and saturation. The myxillin C (3) has a dehydrotyrosine moiety composing the same acyl chain and glycosylation as myxillin B (2). Myxillins A (1) and C (3) were tested for immunomodulating activity in an in vitro dendritic cell model. Dendritic cells matured and stimulated in the presence of myxillin A (1) secreted lower levels of IL-12p40, whilst dendritic cells matured and stimulated in the presence of myxillin C (3) secreted lower levels of IL-10 compared with dendritic cells matured and stimulated in the presence of the solvent alone. These opposing results indicate that the structural differences in the aromatic ring part of the molecules could have an impact on the immunological effects of dendritic cells. These molecules could, therefore, prove to be important in preventing inflammatory diseases on the one hand, and inducing a response to fight tumors and/or pathogens on the other hand. Further studies will be needed to confirm these potential uses.

The biosynthetic products of Chinese insect medicine, Aspongopus chinensis.

A new oxazole (1) was obtained from Chinese insect medicine Aspongopus chinensis, along with three known N-acetyldopamine derivatives (2-4). Their structures were determined on the basis of NMR and ESI-MS analyses. The possible biosynthetic pathways of the isolated compounds are discussed. Cytotoxicities of those compounds against 10 selected cancer cells were measured in vitro.

Two new N-acetyldopamine tetrapolymers from periostracum Cicadae.

Two new N-acetyldopamine tetrapolymers, cicadamide A (1) and cicadamide B (2), were isolated from periostracum Cicadae, and their structures were elucidated as 3-acetylamino-7-(3″-acetylamino-7″-(N-acetyl-2‴-aminoethyl)-1″,4″-benzodioxan-2″-yl)-2-(2'-(3″″,4″″-dihydroxyphenyl)-3'-acetylamino-1',4'-benzodioxan-7'-yl)-1,4-benzodioxane (1) and 3-acetylamino-7-(3″-acetylamino-6″-(N-acetyl-2‴-aminoethyl)-1″,4″-benzodioxan-2″-yl)-2-(2'-(3″″,4″″-dihydroxyphenyl)-3'-acetylamino-1',4'-benzodioxan-7'-yl)-1,4-benzodioxane (2), by the combined analysis of 1D NMR and 2D NMR, and mass spectrometry. Pharmacological investigation on two compounds obtained in this study showed that part of them had anti-inflammatory activities.

Separation and determination of epinephrine and dopamine in traditional Chinese medicines by micellar electrokinetic capillary chromatography with laser induced fluorescence detection.

A micellar electrokinetic capillary chromatography method with laser-induced fluorescence detection was developed for the analysis of epinephrine and dopamine after derivatization with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole. The optimum derivatization conditions were: 30 mM sodium borate (pH adjusted to 8.0 with 1.0 M HCl), reaction time 30 min at 60 degrees C. Baseline separation was achieved within 14 min with a running buffer composed of 10 mM sodium borate + 25 mM sodium dodecyl sulfate (pH adjusted to 9.5 with 0.1 M NaOH) and an applied voltage of 15 kV. Good linearity relationships (correlation coefficients: 0.9991 for epinephrine and 0.9985 for dopamine) between peak areas and concentrations of the analytes were obtained. The detection limits and quantification limits for epinephrine and dopamine were 0.0038 mg/L and 0.013 mg/L, and 0.065 mg/L and 0.020 mg/L, respectively. The method was applied to the analysis of the two compounds in two Chinese medicines with recoveries in the range of 92.6-108.7%.

Antioxidant and anti-inflammatory activities of N-acetyldopamine dimers from Periostracum Cicadae.

A known N-acetyldopamine dimer, (2R,3S)-2-(3',4'-dihydroxyphenyl)-3-acetylamino-7-(N-acetyl-2''-aminoethyl)-1,4-benzodioxane (1) and a new N-acetyldopamine dimer, (2R,3S)-2-(3',4'-dihydroxyphenyl)-3-acetylamino-7-(N-acetyl-2''-aminoethylene)-1,4-benzodioxane (2) were isolated from the methanolic extracts of Periostracum Cicadae. Compounds 1 and 2 inhibited the Cu2+ -mediated, 2,2'-azobis(2-amidinopropane) hydrochloride (AAPH)-mediated, and 3-morpholinosydnonimine (SIN)-1-mediated LDL oxidation in the thiobarbituric acid-reactive substances (TBARS) assay. The antioxidant activities of 1 and 2 were tested with respect to other parameters, such as lag time of conjugated diene formation, relative electrophoretic mobility (REM), and apoB-100 fragmentation on copper-mediated LDL-oxidation. Compounds 1 and 2 also showed 1,1-diphenyl-2-picrylhydrasyl (DPPH) radical scavenging activity. Compound 2 was more efficient than compound 1 at inhibiting the reactive oxygen species (ROS) generation, nitric oxide (NO) production, and nuclear factor-kappaB (NF-kappaB) activity as well as the expression of pro-inflammatory molecules such as inducible nitric oxide synthase (iNOS), interleukin (IL)-6, tumor necrosis factor (TNF)-alpha, and cyclooxygenase (COX)-2 in LPS-induced RAW264.7 cells.

Constituents from the stems of Aristolochia manshuriensis.

In a continuing search for bioactive compounds from Aristolochia species, 28 compounds, including three new constituents, demethylaristofolin E (1), aristomanoside (2), and dehydrooxoperezinone (3), were isolated from an extract of the stems of Aristolochia manshuriensis. The structures of these compounds were established by extensive 1D and 2D NMR spectral studies. Among these compounds, dehydrooxoperezinone (3) was found to inhibit the replication of HIV, with an EC(50) value of 17.5 microg/mL and a therapeutic index of 1.43.

High-performance liquid chromatography of monoamines on phenyl-bound sorbents using organic free mobile phases.

Tryptophan and its metabolites, 5-hydroxytryptophan, 5-hydroxytryptamine, 5-hydroxyindolacetic acid, as well as dopamine, homovanilic acid and 2,3-dihydroxyphenylacetic acid, were separated on phenyl bound silica gel using isocratic elution with phosphate buffer. The method was successfully transferred to several other phenyl HPLC columns from different manufacturers simply by adjusting the pH of the buffer. The method has been validated by the determination of the level of monoamines in rat hypothalamus.

Localization of enzymes and alkaloidal metabolites in Papaver latex.

In continuing studies on the metabolic activity of Papaver somniferum, latex has been examined for its enzyme and alkaloidal metabolite content. After an initial centrifugation of latex at 1000g, the pellet which contained a heterogeneous population of dense organelles was further resolved on sucrose gradients. Of the enzymes monitored, acid phosphatase and L-3,4-dihydroxyphenylalanine decarboxylase were found to be in the latex 1000g supernatant, whereas catecholase (polyphenolase) was localized in two distinct organelles within the 1000g sediment. The lighter organelles, sedimenting at 30% sucrose, contained a soluble enzyme which was readily released on organelle plasmolysis, whereas the catecholase found within the heavier organelles, sedimenting at 55-60% sucrose, was membrane bound and showed significant activity only in the presence of Triton X-100. These latter organelles also contained the alkaloids, including morphine and thebaine, and were observed to readily accumulate [14CH3]morphine. The alkaloid precursor, dopamine, was localized in the same dense vesicle fraction as the alkaloids. The rate of uptake of [7-14C]dopamine into these fractions at room temperature, however, was markedly lower than that of morphine. Electron microscopic examination of the organelles of various densities revealed that they possessed different morphology. The results are consistent with the concept that both the 1000g and supernatant fractions of the latex are required for alkaloid biosynthesis and that a subpopulation of dense organelles found in the 1000g sediment have at least a function as a storage compartment for both alkaloids and their catecholamine precursor.

[Simultaneous extraction and fluorimetric determination of noradrenaline, dopamine, serotonin and 5-hydroxyindoleacetic acid in separate small brain segments]. / Odnovremennaia ékstraktsiia i fliuorimetricheskoe opredelenie noradrenalina, dofamina, serotonina i 5-oksiindoluksusnoi kisloty v otdel'nykh nebol'shikh uchastkakh mozga.

Highly-sensitive and reproducible method is developed for simultaneous assay of noradrenaline, dopamine, serotonin and 5-hydroxyindolylacetic acid in small samples of brain tissue. The procedure comprised extraction of the substances with acidified butanol, reextraction of the compounds with phosphate buffer in presence of isooctane, separation of the amines form precursors and metabolites using ion exchange resin Amberlite CG-50 and of 5-hydroxyindolylacetic acid--on Sephadex G-10.

Alkaloids of Carnegiea gigantea. Arizonine, a new tetrahydroisoquinoline alkaloid.

The alkaloid composition of the giant cactus, Carnegiea gigantea Br. & R., was studied. Chromatographic separation led to the isolation of four tetrahydroisoquinoline alkaloids: carnegine, salsolidine, gigantine and arizonine. The structure of the new natural product, arizonine, was establihsed by spectroscopic data and total synthesis via two independent routes. Salsolidine is reported for the first time in the cacti. Also new to this species are 3-methoxytyramine and 3,4-dimethoxypenethylamine, which were identified in the alkaloid extract by gas chromatography-mass spectrometry. Dopamine was isolated from fresh plant material.

A sensitive radioenzymatic assay for dopamine, norepinephrine, and epinephrine in plasma and tissue.

A double-isotope, radioenzymatic assay for measuring dopamine, norepinephrine, and epinephrine in one sample is described. The assay procedure includes incubation, solvent extraction, and thin-layer chromatography. Dopamine, norepinephrine, and epinephrine were incubated with catechol-O-methyl transferase (COMT) and [3H]S-acenosyl methionine ([3H]SAM) and were converted to the O-methylated tritiated derivatives: [3H]methoxytyramine, [3H]normetanephrine, and [3H]metanephrine, respectively. After several extraction steps the O-methylated products were purified by means of two-dimensional, thin-layer chromatography using silica gel. The thin-layer chromatographic system resulted complete separation of the three O-methylated compounds with an overlap of only 1-2%. The assay was linear from 0 to 5 ng for each catecholamine and had a sensitivity of 10-30 pg. The addition of large amounts of plasma reduced the activity of COMT, but increasing the magnesium concentration in the incubation mixture and the addition of EGTA to plasma samples improved the recoveries. Each sample was corrected for losses incurred during extraction and chromatography by using [14C]methoxytyramine, [14C]normetanephrine, and [14Ci1metanephrine that were added at the end of incubation. Several catechol compounds known to be O-methylated by COMT were examined for crossreactivity. Of the substances tested, only dihydroxyphenylalanine (DOPA) exhibited cross-reactivity. However, the apparent 30% cross-reactivity of DOPA with dopamine was due to the presence of decarboxylase activity in the COMT preparation. As little as 50 mul of trunk plasma from decapitated rats was sufficient for the determination of the three catecholamines.

Identificación de dopamina en la hoja de cordobán por medio de la cromatografía en papel / Identification in the leaf of cordovan via paper chromatography

Los resultados obtenidos en esta investigación demuestran que la parte morada de la hoja cordobán posee una sustancia que faramcológica y cromatológicamente corresponde con la dopamina. Los Rf de dicha sustancia coinciden (en varios solventes) con los de la dopamina utilizada como patrón. Otros investigadores han reportado la presencia de aminas simpaticomiméticas en distintas plantas. Así, Buelow y Gisvild fueron los primeros en encontrar dopamina en la especie Hermidium alipes (S. Watson) de la familia Nictagináceas. Luego Durand y col. la encontraron en las especies Piper amalogo L. (Fam. Piperácea) y Stachytarpheta jamaicensis Vahl. (Fam. Verbenáceas). También se ha demostrado la presencia de noradrenalina en el plátano, la plataína, la papa y en la especie Portulaca olerácea L. (Fam. Portulacáceas)(AU)