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1.
Molecules ; 24(16)2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31408988

RESUMO

As a folk medicine of the Jingpo minority in Yunnan province, the venom of Vespa magnifica has been commonly used for the treatment of rheumatoid arthritis. Quality standardization of the wasp venom is a necessary step for its pharmaceutical research and development. To control the quality of the wasp venom, a method based on high-performance liquid chromatography (HPLC) was developed for chemical fingerprint analysis. In the chromatographic fingerprinting, chemometrics procedures, including similarity analysis (SA), hierarchical clustering analysis (HCA), and principal component analysis (PCA), were applied to classify 134 batches (S1-S134) of wasp venom from different origins. The HPLC fingerprint method displayed good precision (Relative standard deviation, RSD < 0.27%), stability (in 16 h, RSD < 0.34%), and repeatability (RSD < 1.00%). Simultaneously, four compounds (VMS1, VMS2, VMS3, and VMS4) in the wasp venom were purified and identified. VMS1 was 5-hydroxytryptamine, and the other compounds were three peptides that were sequenced as follows: Gly-Arg-Pro-Hyp-Gly-Phe-Ser-Pro-Phe-Arg-Ile-Asp-NH2 (VMS2), Ile-Asn-Leu-Lys-Ala-Ile-Ala-Ala-Leu-Ala-Lys-Lys-Leu-Leu-NH2 (VMS3), and Phe-Leu-Pro-Ile-Ile-Gly-Lys-Leu-Leu-Ser-Gly-Leu-Leu-NH2 (VMS4). The quantifications for these components were 110.2 mg/g, 26.9 mg/g, 216.3 mg/g, and 58.0 mg/g, respectively. The results of this work indicated that the combination of the chemical fingerprint and quantitative analysis offers a reasonable way to evaluate the quality of wasp venom.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Peptídeos/isolamento & purificação , Serotonina/isolamento & purificação , Venenos de Vespas/química , Sequência de Aminoácidos , Animais , Anti-Inflamatórios/química , Artrite Reumatoide/tratamento farmacológico , Cromatografia Líquida de Alta Pressão/normas , Humanos , Medicina Tradicional Chinesa , Medicina Tradicional/métodos , Mapeamento de Peptídeos/métodos , Peptídeos/química , Análise de Componente Principal , Controle de Qualidade , Serotonina/química , Vespas
2.
Biomed Chromatogr ; 33(11): e4650, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31313343

RESUMO

Solid-phase extraction technologies are widely used for sample pretreatment in bioanalysis. Monolithic silica disk-packed spin columns modified with phenylboronate moieties have been developed for the selective extraction of cis-diol compounds such as catecholamines. However, in our preliminary studies, serotonin was found to also be extracted in this treatment, along with catecholamines. In this study, the interaction between serotonin-related compounds (serotonin, tryptophan, 5-hydroxy-tryptophan and 5-hydroxyindoleacetic acid) and phenylboronate moieties was investigated. We found that only serotonin was extracted with phenylboronate-modified monolithic silica, whereas tryptophan, 5-hydroxy-tryptophan and 5-hydroxyindoleacetic acid were not. Hydrophobic interactions rather than ionic interactions were the primary factor for the adsorption of serotonin to phenylboronate. Finally, the selective pretreatment procedure for catecholamines was improved: thus, the method could be applied for the pretreatment of bio-samples.


Assuntos
Ácidos Borônicos/química , Ácido Hidroxi-Indolacético , Serotonina , Extração em Fase Sólida , Triptofano , Adsorção , Catecolaminas , Cromatografia Líquida de Alta Pressão , Interações Hidrofóbicas e Hidrofílicas , Ácido Hidroxi-Indolacético/análise , Ácido Hidroxi-Indolacético/química , Ácido Hidroxi-Indolacético/isolamento & purificação , Serotonina/análise , Serotonina/química , Serotonina/isolamento & purificação , Dióxido de Silício , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Triptofano/análise , Triptofano/química , Triptofano/isolamento & purificação
3.
Otolaryngol Head Neck Surg ; 161(3): 468-471, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31035861

RESUMO

The intricate sensorimotor neural circuits that control swallowing are heavily reliant on serotonin (5-hydroxytryptamine [5-HT]); however, the impact of 5-HT deficiency on swallow function remains largely unexplored. We investigated this using mice deficient in tryptophan-hydroxylase-2 (TPH2), the enzyme catalyzing the rate-limiting step in 5-HT synthesis. Videofluoroscopy was utilized to characterize the swallowing function of TPH2 knockout (TPH2-/-) mice as compared with littermate controls (TPH2+/+). Results showed that 5-HT deficiency altered all 3 stages of swallowing. As compared with controls, TPH2-/- mice had significantly slower lick and swallow rates and faster esophageal transit times. Future studies with this model are necessary to determine if 5-HT replacement may rescue abnormal swallowing function. If so, supplemental 5-HT therapy may have vast applications for a large population of patients with a variety of neurologic disorders resulting in life-diminishing dysphagia, particularly amyotrophic lateral sclerosis and Parkinson's disease, for which 5-HT deficiency is implicated in the disease pathogenesis.


Assuntos
Transtornos de Deglutição/etiologia , Serotonina/deficiência , Animais , Química Encefálica , Feminino , Masculino , Camundongos , Serotonina/isolamento & purificação
4.
ACS Appl Mater Interfaces ; 11(14): 13557-13563, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30873830

RESUMO

Electrochemical sensors have long suffered from issues such as nonspecific adsorption, poor anti-interference ability, and internal and external disturbances. To address these challenges, we developed a facile electrochemical method, which integrated a ratiometric strategy with self-cleaning electrodes. In the novel sensing system, the self-cleaning electrode was realized via forming a hydrophobic layer on carbonized ZIF-67@ZIF-8 (cZIF) by polydimethylsiloxane (PDMS) precursor vaporization. As for ratiometry, it is worth to mention that the measurements were conducted by adding an interior reference (methylene blue) directly into electrolyte solution, which is more facile and flexible to operate compared with conventional ones. Sensing performance of the self-cleaning electrode as well as the newly established ratiometric strategy was explored fully, and it turned out that PDMS@cZIF nanocomposites provided decent electrocatalytic ability, superhydrophobic property, and stability. Furthermore, the ratiometric strategy significantly elevated the robustness and reproducibility of electrochemical sensing. Simultaneous detection of Adr, 5-HT, and Trp was performed under the optimum experimental conditions with wide linear ranges and low detection limits. Finally, the original ratiometric electrochemical sensor was successfully applied for monitoring the three target molecules in biological samples.


Assuntos
Técnicas Biossensoriais , Epinefrina/isolamento & purificação , Serotonina/isolamento & purificação , Triptofano/isolamento & purificação , Técnicas Eletroquímicas , Epinefrina/química , Humanos , Limite de Detecção , Azul de Metileno/química , Nanocompostos/química , Serotonina/química , Triptofano/química
5.
Bioorg Med Chem Lett ; 27(23): 5245-5251, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29102229

RESUMO

Seeds of Carthamus tinctorius L. (Compositae) have been used in Korean traditional medicines for the treatment of cardiovascular and bone diseases. In this study, we investigated the anti-inflammatory effects of known serotonin derivatives (1-9) isolated from the ethyl acetate (EtOAc) soluble fraction from the seeds of C. tinctorius. Compound 2, identified as moschamine, most potently inhibited lipopolysaccharide (LPS)-induced production of prostaglandin E2 (PGE2) and nitric oxide (NO) in RAW 264.7 macrophages. Moschamine concentration-dependently inhibited LPS-induced PGE2 and NO production in RAW 264.7 macrophages. Consistent with these findings, moschamine suppressed the protein and mRNA levels of cyclooxygenase-2 (COX-2), microsomal prostaglandin E2 synthase (mPGES)-1, and inducible NO synthase (iNOS), interleukin (IL)-6, and IL-1ß. In addition, pretreatment of moschamine significantly inhibited LPS-stimulated the transcriptional activity of activator protein-1 (AP-1) and the phosphorylation of signal transducer and activator of transcription (STAT)1/3 in RAW 264.7 macrophages. Moreover, moschamine inhibited LPS-induced the phosphorylation of p38 mitogen-activated protein kinase (p38) and extracellular signal-regulated kinase (ERK), but it had no effect on c-Jun N-terminal kinase (JNK). These results suggest that the mechanism of anti-inflammatory activity of moschamine is associated with the downregulation of COX-2, mPGES-1, iNOS, IL-6, and IL-1ß expression through the suppression of AP-1 and STAT1/3 activation in LPS-induced RAW 264.7 macrophages.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Carthamus tinctorius/química , Mediadores da Inflamação/antagonistas & inibidores , Lipopolissacarídeos/antagonistas & inibidores , Macrófagos/efeitos dos fármacos , Serotonina/análogos & derivados , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Relação Dose-Resposta a Droga , Mediadores da Inflamação/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , Estrutura Molecular , Células RAW 264.7 , Fator de Transcrição STAT1/antagonistas & inibidores , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Serotonina/química , Serotonina/isolamento & purificação , Serotonina/farmacologia , Relação Estrutura-Atividade , Fator de Transcrição AP-1/antagonistas & inibidores , Fator de Transcrição AP-1/metabolismo
6.
Am J Chin Med ; 44(2): 197-226, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27080938

RESUMO

Carthamus tinctorius L. is a multifunctional cash crop. Its flowers and seeds are extensively used in traditional herbal medicine in China, Korea, Japan, and other Asian countries, for treating various ailments such as gynecological, cardiovascular, and cerebrovascular diseases as well as blood stasis and osteoporosis. More than 100 compounds have been isolated and identified from C. tinctorius. Flavonoids and alkaloids, especially the quinochalcone c-glycoside hydroxysafflor yellow A, N-(p-Coumaroyl)serotonin, and N-feruloylserotonin, are responsible for most of the pharmacological activities of C. tinctorius. In this paper, comprehensive and up-to-date information on the phytochemistry and pharmacology of C. tinctorius is presented. This information will be helpful for further explorations of the therapeutic potential of C. tinctorius and may provide future research opportunities.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antineoplásicos Fitogênicos , Conservadores da Densidade Óssea , Fármacos Cardiovasculares , Carthamus tinctorius/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Alcaloides/química , Alcaloides/uso terapêutico , Anti-Infecciosos , Anticoagulantes , Antioxidantes , Chalcona/análogos & derivados , Chalcona/química , Chalcona/isolamento & purificação , Chalcona/farmacologia , Chalcona/uso terapêutico , Flavonoides/química , Flavonoides/uso terapêutico , Flores/química , Humanos , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Quinonas/química , Quinonas/isolamento & purificação , Quinonas/farmacologia , Quinonas/uso terapêutico , Sementes/química , Serotonina/análogos & derivados , Serotonina/química , Serotonina/isolamento & purificação , Serotonina/farmacologia , Serotonina/uso terapêutico
7.
Electrophoresis ; 37(7-8): 1027-30, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26791443

RESUMO

A CE-ESI-MRM-based assay was developed for targeted analysis of serotonin released by human embryonic stem cells-derived serotonergic neurons in a chemically defined environment. A discontinuous electrolyte system was optimized for pH-mediated online stacking of serotonin. Combining with a liquid-liquid extraction procedure, LOD of serotonin in the Krebs'-Ringer's solution by CE-ESI-MS/MS on a 3D ion trap MS was0.15 ng/mL. The quantitative results confirmed the serotonergic identity of the in vitro developed neurons and the capacity of these neurons to release serotonin in response to stimulus.


Assuntos
Eletroforese Capilar/métodos , Células-Tronco Embrionárias Humanas/metabolismo , Serotonina/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Linhagem Celular , Humanos , Concentração de Íons de Hidrogênio , Extração Líquido-Líquido , Serotonina/química , Serotonina/isolamento & purificação , Serotonina/metabolismo , Fatores de Tempo
8.
Free Radic Res ; 50(5): 495-502, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26820827

RESUMO

We previously reported the involvement of serotonin (5-HT) metabolism in cigarette smoke-induced oxidative stress in rat lung in vivo. Here, we report cigarette smoke as a source of serotonin (5-HT) to the airways and aim at investigating the effects of 5-HT on oxidative stress and inflammation in human bronchial epithelial cells (BEAS-2B). A 5-HT analog was identified to be present in aqueous phase cigarette smoke using the LC-MS/MS approach, which was later confirmed by a 5-HT enzyme-linked immune assay (EIA). Furthermore, exposure to 5-HT caused a time-dependent elevation of intracellular ROS level, which was blocked in the presence of apocynin (a NOX inhibitor). In support, the immunoblot analysis indicated that there was an increase in the expression of NOX2 time-dependently. 5-HT-induced elevation of IL-8 at both mRNA and protein levels was observed, which was inhibited by TEMPOL (a free radical scavenger), and inhibitors for p38 MAPK (SB203580) and ERK (U0126), in line with the time-dependent phosphorylation of p38 MAPK and ERK. In conclusion, our findings suggest that 5-HT presented in bronchial epithelium of smokers may be involved in cigarette smoke-induced oxidative stress and inflammation via activation of p38 MAPK and ERK pathway after the formation of free radicals.


Assuntos
Antioxidantes/administração & dosagem , Radicais Livres/metabolismo , Inflamação/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Serotonina/metabolismo , Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Animais , Butadienos/administração & dosagem , Óxidos N-Cíclicos/administração & dosagem , Radicais Livres/toxicidade , Humanos , Imidazóis/administração & dosagem , Inflamação/induzido quimicamente , Inflamação/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nitrilos/administração & dosagem , Piridinas/administração & dosagem , Ratos , Espécies Reativas de Oxigênio/metabolismo , Serotonina/isolamento & purificação , Fumar/efeitos adversos , Marcadores de Spin , Espectrometria de Massas em Tandem , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
9.
Zh Evol Biokhim Fiziol ; 51(2): 127-32, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26027387

RESUMO

The presence and localization of the serotoninergic and FMRFamidergic structures in the nervous system of the trematode Opisthioglyphe ranae, the marsh frog intestinal parasite, was studied using immunocytochemistry. The serotonin-immunoreactive nerve cells and fibers were revealed in the head ganglia, circular commissure, longitudinal nerve cords and their connective commissures, as well as around the oral and ventral suckers, oesophagus and genital pore. FMRF-specific immunoreactivity was observed in the head ganglia, longitudinal nerve cords and terminal parts of the reproductive system. The results obtained are discussed in light of the available data on the presence and functional significance of the above-mentioned neurotransmitters in trematodes.


Assuntos
FMRFamida/metabolismo , Sistema Nervoso/metabolismo , Serotonina/metabolismo , Trematódeos/fisiologia , Animais , FMRFamida/isolamento & purificação , Imuno-Histoquímica , Sistema Nervoso/citologia , Fenômenos Fisiológicos do Sistema Nervoso , Neurotransmissores/metabolismo , Neurotransmissores/fisiologia , Ranidae/parasitologia , Serotonina/isolamento & purificação , Trematódeos/metabolismo
10.
J Chromatogr Sci ; 53(8): 1341-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25744248

RESUMO

High-speed counter-current chromatography (HSCCC) was successfully applied for the preparative separation and purification of N-feruloyl serotonin (NF) and N-(p-coumaroyl) serotonin (NP) from safflower seed meal. After the measurement of partition coefficient of the two target compounds in the two-phase solvent systems, the HSCCC was performed well with a two-phase solvent system composed of CHCl3-methanol-0.1 M HCl at a volume ratio of 1 : 1 : 1, v/v. The upper phase was used as stationary phase and the lower phase was used as mobile phase. Under the optimized condition, 7.5 mg NF and 6.9 mg NP were separated from 40 mg crude sample with the purity of 98.8 and 97.3%, respectively. The structures of the isolated compounds were identified by (1)H NMR and (13)C NMR.


Assuntos
Carthamus tinctorius/química , Distribuição Contracorrente/métodos , Sementes/química , Serotonina/análogos & derivados , Ressonância Magnética Nuclear Biomolecular , Serotonina/análise , Serotonina/química , Serotonina/isolamento & purificação
11.
Biosens Bioelectron ; 52: 411-6, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24125701

RESUMO

A 5,10,15,20-tetrakis(4-pyridyl)-21H,23H-porphyrin (TPyP)-modified self-assembled functional layer was prepared on a fluorine-doped tin oxide (FTO) substrate. We employed a bifunctional molecule, 3-iodopropionate (3IP), to covalently bind TPyP to the FTO substrate. The 3IP-monolayered FTO and the TPyP-3IP-bilayered FTO electrodes were characterized by cyclic voltammetry, electrochemical impedance spectroscopy, and Fourier transform-infrared spectroscopy. Compared to conventional electropolymerized poly(ethylenedioxythiophene):poly(sodium 4-styrenesulfonate) (PEDOT:PSS) film on bare FTO, the PEDOT:PSS film on the TPyP-3IP-bilayered FTO showed better sensitivity and selectivity in monitoring serotonin in the presence of high concentrations of interfering agents such as ascorbic acid, urea, D-(+)-glucose, epinephrine, and L-3,4-dihydroxyphenylalanine. Both PEDOT:PSS films on the bare FTO and the TPyP-3IP-bilayered FTO showed electrocatalytic effects in serotonin detection, and only the TPyP-3IP-based PEDOT:PSS film acted as a pH resistant buffer layer in the selective detection of serotonin.


Assuntos
Flúor/química , Serotonina/isolamento & purificação , Compostos de Estanho/química , Técnicas Biossensoriais , Concentração de Íons de Hidrogênio , Poliestirenos/química , Porfirinas/química
12.
Rapid Commun Mass Spectrom ; 27(21): 2439-52, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24097401

RESUMO

RATIONALE: Absolute quantification of neurotransmitters (NTs) from biological systems is imperative to track how changes in concentration of active neurochemicals may affect biological behavior. A sensitive method for the absolute quantification of multiple NTs in a single method is highly needed. METHODS: A stable-isotope dilution ultrahigh-performance liquid chromatography/mass spectrometry/selected reaction monitoring (UHPLC/MS/SRM) assay has been developed for a sensitive and quantitative assessment of NTs in planaria. We used this method for the simultaneous quantification of 16 NTs. All analytes showed a linear relationship between concentrations (0.78-50 ng/mL), regression coefficients higher than 0.97, accuracy (91-109%) and low coefficients of variation (CVs). The inter-day CVs for the lowest quality controls (1.56 ng/mL) were in the range between 2-11%. RESULTS: The levels of most of the NTs were similar in both sexual and asexual planarians except for glutamic acid, which was about two-fold higher in asexual compared to sexual planarians. We identified high levels of serotonin and failed to detect tryptamine suggesting that the pathway essential for the conversion of tryptophan into tryptamine is absent in planarians. Interestingly, we also found high levels of dopamine and L-DOPA in regenerating planarians suggesting their possible role in regeneration. CONCLUSIONS: For the first time, we developed novel methodology based on UHPLC/MS/SRM and quantified 16 NTs with high sensitivity and specificity from sexual and asexual strains of planarian Schmidtea mediterranea. This method will also have great application in quantifying various NTs with great precision in different model systems.


Assuntos
Neurotransmissores/análise , Planárias/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Cromatografia Líquida de Alta Pressão/métodos , Ácido Glutâmico/análise , Ácido Glutâmico/isolamento & purificação , Limite de Detecção , Neurotransmissores/isolamento & purificação , Planárias/fisiologia , Reprodução , Reprodução Assexuada , Serotonina/análise , Serotonina/isolamento & purificação , Triptaminas/análise , Triptaminas/isolamento & purificação
13.
Plant Biotechnol J ; 11(9): 1103-11, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23980801

RESUMO

Tryptophan decarboxylase (TDC) converts tryptophan (Trp) into tryptamine, consequently increasing the metabolic flow of tryptophan derivatives into the production of secondary metabolites such as indole alkaloids. We inserted an expression cassette containing OsTDC, a putative tryptophan decarboxylase gene from rice, into an expression plasmid vector containing OASA1D, the feedback-resistant anthranilate synthase alpha-subunit mutant (OASA1D). Overexpression of OASA1D has been reported to significantly increase Trp levels in rice. The co-expression of OsTDC and OASA1D in rice calli led to almost complete depletion of the Trp pool and a consequent increase in the tryptamine pool. This indicates that TDC inactivity is a contributory factor for the accumulation of Trp in rice transgenics overexpressing OASA1D. Metabolic profiling of the calli expressing OsTDC and OASA1D revealed the accumulation of serotonin and serotonin-derived indole compounds (potentially pharmacoactive ß-carbolines) that have not been reported from rice. Rice calli overexpressing OASA1D:OASA1D is a novel system for the production of significant amounts of pharmacologically useful indole alkaloids in rice.


Assuntos
Alcaloides Indólicos/metabolismo , Engenharia Metabólica , Oryza/metabolismo , Proteínas de Plantas/genética , Triptofano/metabolismo , Antranilato Sintase/genética , Antranilato Sintase/metabolismo , Descarboxilases de Aminoácido-L-Aromático/genética , Descarboxilases de Aminoácido-L-Aromático/metabolismo , Regulação Enzimológica da Expressão Gênica/genética , Regulação da Expressão Gênica de Plantas/genética , Alcaloides Indólicos/química , Alcaloides Indólicos/isolamento & purificação , Redes e Vias Metabólicas , Metaboloma , Oryza/genética , Fenótipo , Filogenia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Plântula/genética , Plântula/metabolismo , Serotonina/química , Serotonina/isolamento & purificação , Serotonina/metabolismo , Triptaminas/metabolismo
14.
Electrophoresis ; 34(9-10): 1375-82, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23423834

RESUMO

To extend the application of molecularly imprinted polymers, the dual-templates molecularly imprinted monolithic columns were developed in a capillary format. Two templates serotonin and histamine were simultaneously imprinted using two different functional monomers such as methacrylic acid (MAA) and methylenesuccinic acid (MSA) in a mixture of ethylene glycol dimethacrylate (EDMA) as a cross-linker and AIBN as polymerization initiator dissolved in DMF as porogen. The resulting molecular imprinted polymers (MIPs) were characterized based on their performance in the CEC separation of two imprinted templates. The optimization parameters such as pH, ACN composition, and concentration of the eluent were varied to achieve best resolution and efficiency for CEC separation of templates with each MIP column. It was found that the MIP monolith column fabricated using MSA offered better resolution and separation efficiency compared to column fabricated with MAA. This work utilized the dual-templates imprinting approach successfully and broadens the scope of multi-templates imprinting capabilities in capillary format in CEC application.


Assuntos
Eletrocromatografia Capilar/métodos , Histamina/isolamento & purificação , Impressão Molecular/métodos , Serotonina/isolamento & purificação , Reagentes para Ligações Cruzadas/química , Metacrilatos/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Succinatos/química
15.
Biosens Bioelectron ; 42: 434-8, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23228495

RESUMO

A biosensor based on an array of vertically aligned carbon nanofibers (CNFs) grown by plasma enhanced chemical vapor deposition is found to be effective for the simultaneous detection of dopamine (DA) and serotonin (5-HT) in the presence of excess ascorbic acid (AA). The CNF electrode outperforms the conventional glassy carbon electrode (GCE) for both selectivity and sensitivity. Using differential pulse voltammetry (DPV), three distinct peaks are seen for the CNF electrode at 0.13 V, 0.45 V, and 0.70 V for the ternary mixture of AA, DA, and 5-HT. In contrast, the analytes are indistinguishable in a mixture using a GCE. For the CNF electrode, the detection limits are 50 nM for DA and 250 nM for 5-HT.


Assuntos
Técnicas Biossensoriais/métodos , Dopamina/isolamento & purificação , Serotonina/isolamento & purificação , Ácido Ascórbico/química , Carbono/química , Dopamina/química , Concentração de Íons de Hidrogênio , Nanofibras/química , Nanotubos de Carbono , Serotonina/química , Ácido Úrico/química
16.
J Chromatogr A ; 1251: 54-62, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-22771067

RESUMO

The speed of a separation defines the best time resolution possible in online measurements using chromatography. The desired time resolution multiplied by the flow rate of the stream of analyte being sampled defines the maximum volume of sample per injection. The best concentration sensitivity in chromatography is obtained by injecting the largest volume of sample that is consistent with achieving a satisfactory separation, and thus measurement accuracy. Taking these facts together, it is easy to understand that separation speed and concentration sensitivity are linked in this type of measurement. To address the problem of how to achieve the best sensitivity and shortest measurement time simultaneously, we have combined recent approaches to the optimization of the separation itself with an analysis of method sensitivity. This analysis leads to the column diameter becoming an important parameter in the optimization process. We use these ideas in one particular problem presented by online microdialysis sampling/liquid chromatography/electrochemical detection for measuring concentrations of serotonin in the dialysate. In this case the problem becomes the optimization of conditions to yield maximum signal for a given sample volume under the highest speed conditions with a certain required number of theoretical plates. It turns out that the observed concentration sensitivity at an electrochemical detector can be regulated by temperature, particle size, injection volume/column diameter, and void time. The theory was successfully used for optimization of neurotransmitter serotonin measurement by capillary HPLC when sampling from a microdialysis flow stream. The final conditions are: 150 µm i.d., 3.1cm long columns with 1.7 µm particle diameter working at a flow rate of 12 µL/min, an injection volume of 500 nL, and a temperature of 343 K. The retention time for serotonin is 22.7s, the analysis time is about 36 s (which allows for determination of 3-methoxytyramine), and the sampling time is about 0.8 min with a perfusion flow rate of 0.6 µL/min.


Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Microdiálise/métodos , Serotonina/análise , Animais , Química Encefálica , Cateteres de Demora , Masculino , Ratos , Ratos Sprague-Dawley , Sensibilidade e Especificidade , Serotonina/isolamento & purificação
17.
Anal Chim Acta ; 721: 147-53, 2012 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-22405313

RESUMO

We present a comparison of two sensitive methods, HPLC with fluorescence detector (HPLC/FLD) and UPLC with electrospray tandem mass spectrometry (UPLC/MS/MS), for the determination of indoleamine neurotransmitters (NTs) and their metabolites in sea lamprey plasma samples. Liquid-liquid extraction (LLE) and solid-phase extraction (SPE) were also tested for recovery and matrix effect. The recoveries of SPE determined by HPLC/FLD and UPLC/MS/MS ranged from 75 to 123% and 78 to 105%, respectively, while the recoveries of LLE ranged from 45 to 73% and 48 to 75%, respectively. SPE combined with HPLC/FLD and UPLC/MS/MS to determine the target analytes in plasma samples were validated of the sensitivity, reproducibility, accuracy and precision. Both methods exhibited excellent linearity in the range of 0.2-50 ng mL(-1) for all analytes. The limits of detection (LOD) varied from 0.04 ng mL(-1) to 0.13 ng mL(-1) for HPLC/FLD method and 0.003 ng mL(-1) to 0.02 ng mL(-1) for UPLC/MS/MS method. The inter-day accuracy ranged from 82.5 to 127.0% for HPLC/FLD and 93.0 to 113.0% for UPLC/MS/MS. The inter-day precision ranged from 9.9 to 32.3% for HPLC/FLD and 5.4 to 13.2% for UPLC/MS/MS. These results demonstrated that the values obtained by both methods were within the satisfactory range and the UPLC/MS/MS method provided more accurate and precise measurements than HPLC/FLD method. The comparison is of great importance to determine the available detectors, considering the complexity and expensiveness versus quality parameters. These two methods were applied to the analysis of four important indoleamine neurotransmitter analytes (5-hydroxytryptamine, 5-hydroxyindole-3-acetic acid, tryptamine and melatonin) in sea lamprey plasma samples.


Assuntos
Cromatografia Líquida de Alta Pressão , Neurotransmissores/sangue , Petromyzon/metabolismo , Espectrometria de Massas em Tandem , Aminas/sangue , Aminas/isolamento & purificação , Animais , Indóis/sangue , Indóis/isolamento & purificação , Extração Líquido-Líquido , Melatonina/sangue , Melatonina/isolamento & purificação , Neurotransmissores/isolamento & purificação , Neurotransmissores/metabolismo , Serotonina/sangue , Serotonina/isolamento & purificação , Extração em Fase Sólida , Espectrometria de Fluorescência , Triptaminas/sangue , Triptaminas/isolamento & purificação
18.
Phytother Res ; 26(5): 722-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22021176

RESUMO

As part of the search for naturally derived α-glucosidase inhibitors, the chemical components isolated from safflower seed (Carthamus tinctorius L.) were evaluated. The compounds active as α-glucosidase inhibitors were serotonin derivatives (e.g. N-p-coumaroyl serotonin (1) and N-feruloyl serotonin (2)). These compounds showed a potent inhibitory activity, the 50% inhibitory concentration (IC(50) ) values were calculated as 47.2 µm (1) and 99.8 µm (2) while that of the reference drugs acarbose and 1-deoxynojirimycin were evaluated as 907.5 µm and 278.0 µm, respectively. Regarding the structure of the serotonin derivative, the existence of the hydroxyl group at 5-position in the serotonin moiety and the linkage of cinnamic acid and serotonin are essential for α-glucosidase inhibitory activities. These results are helpful for the proper use of safflower seed as traditional medicine for the treatment of diabetes, moreover, it could serve to develop medicinal preparations as supplements and functional foods for diabetes. In particular, the serotonin compounds could be used as a lead compound for a new potential α-glucosidase inhibitor derived from the plant.


Assuntos
Carthamus tinctorius/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Inibidores Enzimáticos/isolamento & purificação , Inibidores de Glicosídeo Hidrolases , Sementes/química , Serotonina/análogos & derivados , 1-Desoxinojirimicina/farmacologia , Acarbose/farmacologia , Cinamatos/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Concentração Inibidora 50 , Plantas Medicinais/química , Serotonina/química , Serotonina/isolamento & purificação , Serotonina/farmacologia , alfa-Glucosidases/metabolismo
19.
Pharmacol Rep ; 63(3): 790-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21857090

RESUMO

N-feruloylserotonin (N-f-5HT) isomers, isolated from seeds of Leuzea carthamoides (Wild) DC, inhibited dose-dependent oxidative burst in human whole blood and isolated neutrophils in vitro, which were measured by luminol- and/or isoluminol-enhanced chemiluminescence in the following rank order of stimuli: PMA > OpZ > calcium ionophore A23187. In isolated neutrophils that were stimulated with PMA, N-f-5HT isomers were effective against extracellular and intracellular reactive oxygen species. Liberation of ATP, analysis of apoptosis, and recombinant caspase-3 activity revealed that N-f-5HT isomers, used in concentrations up to 100 µM, did not alter the viability and integrity of isolated neutrophils. Western blot analysis documented that in concentrations of 10 and 100 µM, N-f-5HT isomers significantly decreased PMA-induced phosphorylation of PKC α/ß II. The results suggest that N-f-5HT isomers are an effective, naturally occurring substance with a potent pharmacological effect on the oxidative burst of human neutrophils. It should be further investigated for its pharmacological activity against oxidative stress in ischemia-reperfusion, inflammation and other pathological conditions.


Assuntos
Neutrófilos/efeitos dos fármacos , Proteína Quinase C/metabolismo , Explosão Respiratória/efeitos dos fármacos , Serotonina/análogos & derivados , Adulto , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Isomerismo , Leuzea/química , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Sementes , Serotonina/química , Serotonina/isolamento & purificação , Serotonina/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Adulto Jovem
20.
Anal Chim Acta ; 699(2): 242-8, 2011 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-21704780

RESUMO

Capillary electrophoresis (CE) has been investigated for the analysis of some neurotransmitters, dopamine (DA), 3-methoxytyramine (3-MT) and serotonin (5-hydroxytryptamine, 5-HT) at nanomolar concentrations in urine. Field-amplified sample injection (FASI) has been used to improve the sensitivity through the online pre-concentration samples. The cationic analytes were stacked at the capillary inlet between a zone of low conductivity - sample and pre-injection plug - and a zone of high conductivity - running buffer. Several FASI parameters have been optimized (ionic strength of the running buffer, concentration of the sample protonation agent, composition of the sample solvent and nature of the pre-injection plug). Best results were obtained using H(3)PO(4)-LiOH (pH 4, ionic strength of 80 mmol L(-1)) as running buffer, 100 µmol L(-1) of H(3)PO(4) in methanol-water 90/10 (v/v) as sample solvent and 100 µmol L(-1) of H(3)PO(4) in water for the pre-injection plug. In these conditions, the linearity was verified in the 50-300 nmol L(-1) concentration range for DA, 3-MT and 5-HT with a determination coefficient (r(2)) higher than 0.99. The limits of quantification (10 nmol L(-1) for DA and 3-MT, 5.9 nmol L(-1) for 5-HT) were 500 times lower than those obtained with hydrodynamic injection. However, if this method is applied to the analysis of neurotransmitters in urine, the presence of salts in the matrix greatly reduces the sensitivity of the FASI/CE-UV method.Therefore, a solid phase extraction (SPE) on a dedicated imprinted polymer (MIP) was developed to extract specific neurotransmitters, catecholamines, metanephrines and indolamines, from urine. Matrix salts were thus discarded after sample extraction on AFFINIMIP™ Catecholamine & Metanephrine (100mg) cartridge. Therefore, lower limits of quantification were determined in artificial urine (46 nmol L(-1) for DA, 11 nmol L(-1) for 3-MT and 6 nmol L(-1) for 5-HT).The application of this protocol MIP-SPE/FASI-CE-UV analysis of neurotransmitters in human urine gave rise to electropherograms with a very good base line and signal to noise ratios above 15.


Assuntos
Eletroforese Capilar/métodos , Neurotransmissores/urina , Polímeros/química , Extração em Fase Sólida/métodos , Dopamina/análogos & derivados , Dopamina/isolamento & purificação , Dopamina/urina , Eletroforese Capilar/instrumentação , Impressão Molecular , Neurotransmissores/isolamento & purificação , Sais/química , Serotonina/isolamento & purificação , Serotonina/urina
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