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1.
Brain Behav Immun ; 66: 244-256, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28690033

RESUMO

Toll-like receptor 4 (TLR4) and C5aR1 (CD88) have been recognized as potential therapeutic targets for the reduction of inflammation and secondary damage and improvement of outcome after ischemia and reperfusion (I/R). The inflammatory responses which induce cell apoptosis and necrosis after I/R brain injury lead to a limited process of neural repair. To further comprehend how these targets function in I/R state, we investigated the pathological changes and TLR4 and C5aR1 signaling pathways in vitro and in vivo models of I/R brain injury in this study. Meanwhile, we explored the roles of schisantherin A on I/R brain injury, and whether it exerted neuroprotective effects by regulating the TLR4 and C5aR1 signaling pathways or not. The results showed that schisantherin A significantly reduced the neuronal apoptosis induced by oxygen and glucose deprivation and reperfusion (OGD/R) injury in primary culture of rat cortical neurons. Also, schisantherin A alleviated neurological deficits, reduced infarct volume, attenuated oxidation stress, inflammation and apoptosis in ischemic parietal cortex of rats after middle cerebral artery occlusion and reperfusion (MCAO/R) injury. Moreover, the activated TLR4 and C5aR1 signaling pathways were inhibited by schisantherin A treatment. In conclusion, TLR4 and C5aR1 played a vital role during I/R brain injury in rats, and schisantherin A exhibited neuroprotective effects by TLR4 and C5aR1 signaling pathways. These findings also provided new insights that would aid in elucidating the effect of schisantherin A against cerebral I/R and support the development of schisantherin A as a potential treatment for ischemic stroke.


Assuntos
Isquemia Encefálica/metabolismo , Ciclo-Octanos/administração & dosagem , Dioxóis/administração & dosagem , Lignanas/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Receptor da Anafilatoxina C5a/metabolismo , Traumatismo por Reperfusão/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Apoptose/efeitos dos fármacos , Isquemia Encefálica/complicações , Isquemia Encefálica/prevenção & controle , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Inflamação/etiologia , Inflamação/metabolismo , Necrose/tratamento farmacológico , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo , Lobo Parietal/efeitos dos fármacos , Lobo Parietal/metabolismo , Lobo Parietal/patologia , Cultura Primária de Células , Ratos Sprague-Dawley , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/prevenção & controle , Transdução de Sinais
2.
Mol Neurobiol ; 54(3): 2126-2142, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-26924319

RESUMO

Ischemic stroke is a major disability and cause of death worldwide due to its narrow therapeutic time window. Neuroprotective agent is a promising strategy to salvage acutely ischemic brain tissue and extend the therapeutic time window for stroke treatment. In this study, we aimed to evaluate the neuroprotective effects of isoquercetin in (1) primary culture of rat hippocampal neurons exposure on oxygen and glucose deprivation and reperfusion (OGD/R) injury and (2) rats subjected to transient middle cerebral artery occlusion and reperfusion (MCAO/R) injury. The results showed that isoquercetin post-treatment reduced the infarct size, number of apoptotic cells, oxidative stress, and inflammatory response after ischemia and reperfusion injury. The underlying mechanism study indicated that the neuroprotective effects of isoquercetin were elicited via suppressing the activation of toll-like receptor 4 (TLR4), nuclear factor-kappa B (NF-κB) and caspase-1; the phosphorylation of ERK1/2, JNK1/2, and p38 mitogen-activated protein kinase (MAPK); and the secretion of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and IL-6. In addition, isoquercetin also effectively alleviated hippocampus neuron apoptosis by regulation of cyclic AMP responsive element-binding protein (CREB), Bax, Bcl-2, and caspase-3. Our report provided new considerations into the therapeutic action and the underlying mechanisms of isoquercetin to improve brain injury in individuals who have suffered from ischemic stroke. As a potent anti-inflammatory and anti-oxidative compound with neuroprotective capacities, the beneficial effects of isoquercetin when used to treat ischemic stroke and related diseases in humans warrant further studies.


Assuntos
Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Região CA1 Hipocampal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Quercetina/análogos & derivados , Animais , Isquemia Encefálica/patologia , Região CA1 Hipocampal/citologia , Região CA1 Hipocampal/metabolismo , Células Cultivadas , Inflamação/tratamento farmacológico , Isquemia/tratamento farmacológico , Masculino , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Quercetina/farmacologia , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia
3.
Fitoterapia ; 115: 57-63, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27702666

RESUMO

White Mulberry Root-bark (WMR) is an edible Chinese herbal used for the treatment of inflammation, nephritis and asthma. This study aimed to investigate the inhibitory effects of ethanol extract from WMR against human carboxylesterase 2 (hCE2), as well as to identity and character natural hCE2 inhibitors in this herbal. Our results demonstrated that the ethanol extract of WMR displayed potent inhibitory effects against hCE2, while three major bioactive constitutes in WMR were identified on the basis of LC fingerprinting combined with activity-based screening of LC fractions. Three bioactive compounds including SD, KG and SC were efficiently identified by comparison of LC retention times, UV and MS spectral data, with the help of authentic standards. The inhibition potentials and inhibition types of these natural compounds against hCE2 were further investigated in human liver microsomes. The results demonstrated that these bioactive compounds are potent non-competitive inhibitors against hCE2, with the Ki values ranging from 0.76µM to 1.09µM. All these findings suggested that three abundant natural compounds in WMR displayed potent inhibitory effects against hCE2, which could be used as lead compounds to develop more potent hCE2 inhibitors for the alleviation of hCE2-mediated severe delayed-onset diarrhea.


Assuntos
Carboxilesterase/antagonistas & inibidores , Microssomos Hepáticos/efeitos dos fármacos , Morus/química , Extratos Vegetais/química , Cromatografia Líquida , Medicamentos de Ervas Chinesas/química , Humanos , Estrutura Molecular , Casca de Planta/química , Raízes de Plantas/química , Espectrometria de Massas em Tandem
4.
Cell Biol Int ; 39(12): 1418-24, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26289388

RESUMO

Dibenzocyclooctadiene lignans, the major active components of fruit of Schisandra chinensis (Turcz.) Baill., have been found to have activities that could prevent prostate and thyroid cancer, hepatotoxicity, oxidative stress-induced cerebral injury, etc. This study was conducted to evaluate the effects of seven dibenzocyclooctadiene lignans of Schisandra chinensis and explore the possible mechanisms in the human neuroblastoma SH-SY5Y cells exposed on serum and glucose deprivation (SGD) injury. The structure-activity relationships were also analyzed. Cell viability and lactate dehydrogenase (LDH) release were determined to evaluate cell injury. Inflammation and apoptosis-related protein levels were detected to elucidate the possible mechanisms. Schisantherin A, schizandrin C, and schizandrol B were found to have stronger protective effects than schizandrin A, schizandrin B, and schisanhenol in SH-SY5Y cells against SGD injury. Moreover, the protective effects of these lignans were possibly exhibited by regulating inflammation and apoptosis-related proteins in SH-SY5Y cells after SGD injury, supporting their beneficial effects for the prevention of cell injury in the pathogenesis of the central nervous system diseases, including ischemia stroke. The number and position of hydroxyl group and methylenedioxy in these lignans may be required for their effects.


Assuntos
Meios de Cultura Livres de Soro/toxicidade , Ciclo-Octanos/farmacologia , Glucose/deficiência , Lignanas/farmacologia , Schisandra , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Ciclo-Octanos/isolamento & purificação , Humanos , Lignanas/isolamento & purificação
5.
J. physiol. biochem ; 70(3): 735-747, sept. 2014.
Artigo em Inglês | IBECS | ID: ibc-127318

RESUMO

Brain ischemia appears to be associated with innate immunity. Recent reports showed that C3a and C5a, as potent targets, might protect against ischemia induced cell death. In traditional Chinese medicine, the fruit of Schizandra chinesis Baill (Fructus schizandrae) has been widely used as a tonic. In the present study, we sought to evaluate the neuroprotective effects of schizandrin A, a composition of S. chinesis Baill, against oxygen and glucose deprivation followed by reperfusion (OGD/R)-induced cell death in primary culture of rat cortical neurons, and to test whether C3a and C5a affected cortical neuron recovery from ischemic injury after schizandrin A treatment. The results showed that schizandrin A significantly reduced cell apoptosis and necrosis, increased cell survival, and decreased intracellular calcium concentration ([Ca2+]i) and lactate dehydrogenase (LDH) release in primary culture of rat cortical neurons after OGD/R. Mechanism studies suggested that the modulation of extracellular-regulated kinase (ERK), c-Jun NH2-terminal kinases (JNK), and p38, as well as caspase-3 activity played an important role on the progress of neuronal apoptosis. C5aR participated in the neuroprotective effect of schizandrin A in primary culture of rat cortical neurons after OGD/R. Our findings suggested that schizandrin A might act as a candidate therapeutic target drug used for brain ischemia and related diseases


Assuntos
Animais , Ratos , Fármacos Neuroprotetores/farmacocinética , Schisandraceae , Neurônios , Traumatismo por Reperfusão/prevenção & controle , Proteínas Quinases Ativadas por Mitógeno , Apoptose , Isquemia/tratamento farmacológico , Modelos Animais de Doenças , Substâncias Protetoras/farmacocinética , Extratos Vegetais/farmacocinética
6.
J Physiol Biochem ; 70(3): 735-47, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24986222

RESUMO

Brain ischemia appears to be associated with innate immunity. Recent reports showed that C3a and C5a, as potent targets, might protect against ischemia induced cell death. In traditional Chinese medicine, the fruit of Schizandra chinesis Baill (Fructus schizandrae) has been widely used as a tonic. In the present study, we sought to evaluate the neuroprotective effects of schizandrin A, a composition of S. chinesis Baill, against oxygen and glucose deprivation followed by reperfusion (OGD/R)-induced cell death in primary culture of rat cortical neurons, and to test whether C3a and C5a affected cortical neuron recovery from ischemic injury after schizandrin A treatment. The results showed that schizandrin A significantly reduced cell apoptosis and necrosis, increased cell survival, and decreased intracellular calcium concentration ([Ca(2+)]i) and lactate dehydrogenase (LDH) release in primary culture of rat cortical neurons after OGD/R. Mechanism studies suggested that the modulation of extracellular-regulated kinase (ERK), c-Jun NH2-terminal kinases (JNK), and p38, as well as caspase-3 activity played an important role on the progress of neuronal apoptosis. C5aR participated in the neuroprotective effect of schizandrin A in primary culture of rat cortical neurons after OGD/R. Our findings suggested that schizandrin A might act as a candidate therapeutic target drug used for brain ischemia and related diseases.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Ciclo-Octanos/farmacologia , Lignanas/farmacologia , Fármacos Neuroprotetores/farmacologia , Compostos Policíclicos/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Cálcio/metabolismo , Caspase 3/metabolismo , Morte Celular/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Glucose/metabolismo , L-Lactato Desidrogenase/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Medicina Tradicional Chinesa , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Fitoterapia , Ratos , Receptor da Anafilatoxina C5a/genética , Receptor da Anafilatoxina C5a/metabolismo , Receptores Acoplados a Proteínas-G/genética , Receptores Acoplados a Proteínas-G/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Schisandra , Transdução de Sinais/efeitos dos fármacos
7.
J Neurosci Res ; 92(7): 944-54, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24687774

RESUMO

Mulberroside A is a natural polyhydroxylated stilbene compound present at relatively high abundance in the roots and twigs of Morus alba L. It is known for its nephroprotective, hypoglycemic, and antidiabetic effects. Because its metabolite, oxyresveratrol, possessed purported anti-inflammatory and neuroprotective effects, we proposed that mulberroside A may elicit neuroprotective effects that can be used in the treatment of brain ischemic injury. Therefore, we decided to investigate the pharmacological properties of mulberroside A in primary culture of rat cortical neurons after oxygen-glucose deprivation followed by reperfusion (OGD/R), evaluating its ability to counteract the hypoxia-ischemia impairment. The results showed that mulberroside A elicited neuroprotective effects comparable to nimodipine. The mechanistic studies showed that mulberroside A decreased the expressions of tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, and IL-6 and inhibited the activation of NALP3, caspase-1, and nuclear factor-κB and the phosphorylation of extracellular signal-regulated protein kinases, the c-Jun N-terminal kinase, and p38, exhibiting anti-inflammatory antiapoptotic effects. Our results also further demonstrate that the proinflammatory cytokines of IL-1ß, IL-6, and TNF-α are promising targets for treatment of cerebral ischemic injury. Although further investigation is required for its development, all of these findings led us to speculate that mulberroside A is a candidate for the treatment of ischemic stroke, which would act as a multifactorial neuroprotectant.


Assuntos
Córtex Cerebral/citologia , Dissacarídeos/farmacologia , Glucose/deficiência , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estilbenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas de Transporte , Caspase 1/metabolismo , Hipóxia Celular , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Embrião de Mamíferos , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ratos , Ratos Sprague-Dawley , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais/efeitos dos fármacos
8.
Neurochem Int ; 63(8): 741-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24099731

RESUMO

In the present study, oxygen-glucose deprivation followed by reperfusion (OGD/R), an in vitro model of ischemia, was used to evaluate the neuroprotective effect of isoquercetin in primary culture of rat cortical neuronal cells. It was found that isoquercetin administered prior to the insult could prevent OGD/R-induced intracellular calcium concentrations ([Ca(2+)]i) increase, lactate dehydrogenase (LDH) release and cell viability decrease. For the first time, isoquercetin is described as a neuroprotective agent that potentially explains the alleviation and prevention from OGD/R-induced injury in neurons. Mechanistic studies showed that the neuroprotective effect of isoquercetin was carried out by anti-inflammatory signaling pathway of inhibiting protein expression of toll-like receptor 4 (TLR4) and nuclear factor-kappa B (NF-κB), and mRNA expression of TNF-α and IL-6, accompanied by the anti-apoptotic signaling pathway of deactivation of extracellular-regulated kinase (ERK), Jun kinase (JNK) and p38, and inhibition of activity of caspase-3. Therefore, these studies highlighted the confirmation of isoquercetin, a flavonoid compound, as an anti-inflammation and anti-apoptosis factor which might be used as a therapeutic strategy for the ischemia/reperfusion (I/R) brain injury and related diseases.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Glucose/metabolismo , Neurônios/efeitos dos fármacos , Oxigênio/metabolismo , Quercetina/farmacologia , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Animais , Sequência de Bases , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Primers do DNA , NF-kappa B/metabolismo , Neurônios/metabolismo , Quercetina/química , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Molecules ; 16(4): 3345-50, 2011 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-21512442

RESUMO

Three diterpenoid alkaloids, including an unreported compound, were isolated from the roots of Aconitum kusnezoffii Reichb. On the basis of spectral analysis, these three compounds were determined to be 1,15-dimethoxy-3-hydroxy-14-benzoyl-16-ketoneoline, benzoylaconine and aconitine.


Assuntos
Aconitum/química , Alcaloides/análise , Diterpenos/análise , Raízes de Plantas/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho
10.
Talanta ; 81(4-5): 1870-6, 2010 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20441989

RESUMO

A dual retention combined with reversed-phase liquid chromatography (RP-LC) and hydrophilic interaction chromatography (HILIC) has been observed on beta-cyclodextrin (beta-CD) bonded stationary phase. A typical U-shaped retention curve was achieved owing to dual retention mechanism. Based on this observation, a beta-CD column can be operated under reversed-phase liquid chromatography (RP-LC) and hydrophilic interaction chromatography (HILIC) modes. Two-dimensional liquid chromatography (2D-LC) analysis can be realized on just a beta-CD column by switching these two different separation modes. In this study, off-line 2D-LC analysis for a natural product was carried out to prove the orthogonal separation between RP-LC and HILIC modes on a Click beta-CD column. Herba Hedyotis Diffusae, the whole grass of Hedyotis Diffusae wild was extracted with water, pretreated with macroporous resin and then first separated at RP-LC mode on the Click beta-CD column to obtain successive fractions, which were then reanalyzed at HILIC mode on the same Click beta-CD column. The result proved that both separation modes on the Click beta-CD column have good retention and peak shape, and these two separation modes have good orthogonality. 2D-LC analysis revealed abundant information in the natural product. Especially numerous minor components were enriched and separated. The mobile phase used in RP-LC and HILIC modes can be same and the switch between these two separation modes is easily realized by changing the ratio of the acetonitrile and water. Hence the mobile phase in this 2D-LC system is completely compatible. This advantage makes this combination is an appropriate 2D-LC method for the solutes having retention at both separation modes.


Assuntos
Cromatografia de Fase Reversa/métodos , Cromatografia/métodos , beta-Ciclodextrinas/química , Técnicas de Química Analítica , Cromatografia Líquida/métodos , Poaceae , Água/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos
11.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 22(2): 109-12, 2010 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-20170617

RESUMO

OBJECTIVE: To observe effects of effective components compatibility of aqueous extracts of Salviae Miltiorrhizae and Rhizoma Chuanxiong on myocardial ischemia/reperfusion (I/R) injury in rat. METHODS: Sprague-Dawley (SD) rats were randomly divided into sham group, model group, Guanxinning injection group and effective components of aqueous extracts from Salviae Miltiorrhizae and Rhizoma Chuanxiong salvianolic low dose group and high dose group, with 10 rats in each group. The myocardial I/R injury model was reproduced by ligation of the left anterior descending artery, and the experimental drugs were injected intravenously via femoral vein at 10 minutes after ligation. 2.88 g/kg Guanxinning injection was given in Guanxinning group, and 2.43 g/kg or 4.86 g/kg effective components of aqueous extracts of Salviae Miltiorrhizae and Rhizoma Chuanxiong salvianolic was given in low dose group and high dose group, respectively, and equal volume of normal saline was given in sham group and model group. The anesthetic rats were sacrificed 40 minutes after ischemia and 120 minutes of reperfusion. Blood samples were collected before rats were sacrificed. The contents of serum troponin T (cTnT) and MB isoenzyme of creatine kinase (CK-MB) were determined, 6-keto-prostaglandin F(1 alpha) (6-keto-PGF(1 alpha)), thromboxane B(2) (TXB(2)) and platelet aggregation rate in blood plasma were assessed, and the degree of myocardial infarction in rats was determined. RESULTS: The myocardial infarction size in combined Salviae Miltiorrhizae and Rhizoma Chuanxiong low dose group and high dose group [(23.0+/-3.8)%, (20.8+/-4.7)%] were lower significantly than that in model group [(29.1+/-3.2)%, P<0.05 and P<0.01], the contents of serum cTnT [(0.78+/-0.29) mg/L, (0.76+/-0.29) mg/L] and CK-MB [(891.5+/-252.5) U/L, (759.5+/-191.3) U/L] were lower significantly than those in model group [(1.04+/-0.14) mg/L, (1 268.2+/-256.5) U/L, all P<0.05]. The level of 6-keto-PGF(1 alpha) was higher significantly in high dose of the combination group than that in model group [(206.7+/-35.6) ng/L vs. (138.6+/-28.9) ng/L, P<0.05], and platelet aggregation rate was inhibited significantly [(49.4+/-9.3)% vs. (77.1+/-16.7)%, P<0.05]. CONCLUSION: Effective components compatibility of aqueous extracts from Salviae Miltiorrhizae and Rhizoma Chuanxiong may reduce significantly the size of myocardial infarct and blood content of myocardial enzyme CK-MB and cTnT, and increase the ratio of 6-keto-PGF(1 alpha)/TXB(2), thus reducing myocardial I/R injury.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Salvia miltiorrhiza/química , Animais , Modelos Animais de Doenças , Feminino , Masculino , Traumatismo por Reperfusão Miocárdica/sangue , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Rizoma/química
12.
J Pharm Biomed Anal ; 50(1): 2-8, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19428213

RESUMO

Polymethoxylated flavones (PMFs), as potential cancer chemopreventive agents, are widely distributed in Citrus genus. In this study, a selected ion monitoring-tandem mass (SIM-MS/MS) method for the rapid identification of PMFs in Fructus aurantii (F. aurantii) with ultra-performance liquid chromatography (UPLC) coupled to quadrupole, hybrid orthogonal acceleration time-of-flight tandem mass spectrometer (Q-TOFMS/MS) was proposed. The MS data for candidates, containing accurate mass and isotopic patterns for both precursors and their fragment ions, were acquired selectively. Based on the MS data, the mass spectrometric fingerprint (MSFP) for candidates, consisting of chemical formula and dissociation pattern, was determined. Comparing the MSFPs of the observed compounds with the diagnostic MSFP of the species, 44 PMFs were tentatively identified. The method was validated by tangeretin and sinensetin, two representative compounds of PMFs, and was considered to be suitable for the rapid screening of PMFs in crude and partially purified samples.


Assuntos
Cromatografia Líquida/métodos , Flavonas/análise , Plantas/química , Espectrometria de Massas em Tandem/métodos
13.
J Asian Nat Prod Res ; 11(6): 569-75, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20183292

RESUMO

Investigation of the EtOH extract of the rhizomes of Curcuma longa led to the isolation of two new sesquiterpenes, 2-methoxy-5-hydroxybisabola-3,10-diene-9-one (1) and 2,8-epoxy-5-hydroxybisabola-3,10-diene-9-one (2), one new monoterpene, 2-(2,5-dihydroxy-4-methylcyclohex-3-enyl)propanoic acid (3), together with five known sesquiterpenes (4-8). Among the known compounds, bisacurone A (5) and 4-methylene-5-hydroxybisabola-2,10-diene-9-one (6) were isolated from C. longa and genus Curcuma for the first time, respectively. Their structures were established on the basis of various spectroscopic analyses including HR-ESI-MS, 1D and 2D NMR, IR spectra, and by comparison of their spectral data with those of related compounds.


Assuntos
Curcuma/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Monoterpenos/isolamento & purificação , Sesquiterpenos/isolamento & purificação , Cicloexanóis/química , Cicloexanóis/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Estrutura Molecular , Monoterpenos/química , Ressonância Magnética Nuclear Biomolecular , Rizoma/química , Sesquiterpenos/química
14.
J Chromatogr A ; 1216(11): 2033-44, 2009 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-18656880

RESUMO

Separation techniques with high efficiency and sensitive detection have been widely used for quality control of traditional Chinese medicines (TCMs). High-performance liquid chromatography, gas chromatography, and capillary electrophoresis are commonly used to separate various components in TCMs. Ultraviolet detection, fluorescence detection, evaporative light-scattering detection, mass spectrometry and nuclear magnetic resonance can be applied to separation techniques for qualitative and quantitative analysis of TCMs. The development of quality control for TCMs based on quantitative and qualitative analysis from 2000 to 2007 are reviewed; the fingerprint technique is also discussed due to its broad application in the quality control of TCMs. Prospects for further research based on our primary results are also discussed.


Assuntos
Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/normas , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Eletroforese Capilar , Espectrometria de Massas , Medicina Tradicional Chinesa , Ressonância Magnética Nuclear Biomolecular , Controle de Qualidade
15.
J Pharm Biomed Anal ; 49(2): 207-13, 2009 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-19091508

RESUMO

Off-line two-dimensional reversed-phase liquid chromatography (2D-RPLC) coupled to electrospray ionization-ion trap mass spectrometry (ESI-ITMS) was operated in positive mode (PI) to characterize polymethoxylated flavonoids (PMFs) in botanical sample. The fragments of [M+H-nx15](+) produced by loss of one or more methyl group from the protonated molecules, as well as [M+H-14](+), [M+H-29](+), [M+H-33](+), [M+H-43](+), [M+H-46](+) and [M+H-61](+) fragments formed the multiple MS (MS(n)) "fingerprint" of PMFs. 42 target compounds were tentatively identified from the extract of Fructus aurantii (F. aurantii) based on this "fingerprint". Experimental outcomes indicated that the application of 2D separation method can reduce the matrix suppression of analytes caused by the coelution with interferential components and the column overloading of interferential components. 42 versus 23 target compounds were detected through 2D versus 1D method, which confirm the superiority of 2D coupled to MS in elimination of matrix effects.


Assuntos
Medicamentos de Ervas Chinesas/química , Flavonas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Flavonas/química , Flavonas/isolamento & purificação , Estrutura Molecular , Peso Molecular , Extratos Vegetais/química , Padrões de Referência , Espectrofotometria Ultravioleta
16.
J Chromatogr A ; 1216(11): 2136-41, 2009 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-18440542

RESUMO

Fingerprint analysis is considered one of the most powerful approaches to quality control in traditional Chinese medicines (TCMs). In this study, a binary chromatographic fingerprint analysis was developed using hydrophilic interaction chromatography (HILIC) and reversed-phase liquid chromatography (RPLC) to gain more chemical information about polar compounds and weakly polar compounds. This method was used to construct a chromatographic fingerprint of Ligusticum chuanxiong. The two chromatographic methods demonstrated good precision, reproducibility, and stability, with relative standard deviations of <2% for retention time and 7% for peak area for both HILIC and RPLC separations. Data from the analysis of 14 samples by HILIC and RPLC were processed with similarity analysis, with correlation coefficients and congruence coefficients. This binary fingerprint analysis, using two chromatographic modes, is a powerful tool for characterizing the quality of samples, and can be used for the comprehensive quality control of TCMs.


Assuntos
Cromatografia Líquida/métodos , Medicamentos de Ervas Chinesas/química , Estabilidade de Medicamentos , Interações Hidrofóbicas e Hidrofílicas , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
J Asian Nat Prod Res ; 10(7-8): 729-33, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18696324

RESUMO

Two new isoflavone diglycosides, formononetin 8-C-[beta-D-apiofuranosyl-(1 --> 6)]-beta-D-glucopyranoside (1) and formononetin 8-C-[beta-D-xylopyranosyl-(1 --> 6)]-beta-D-glucopyranoside (2), were isolated from the roots of Pueraria lobata, together with four known compounds, 4'-methoxypuerarin (3), daidzin (4), genistin (5), and daidzein (6). The structures of these compounds were elucidated by the spectroscopic methods.


Assuntos
Glicosídeos/química , Isoflavonas/química , Pueraria/química , Estrutura Molecular , Raízes de Plantas/química
18.
Huan Jing Ke Xue ; 29(2): 525-8, 2008 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-18613531

RESUMO

The article studied the thermal desorption behavior of PCDD/Fs on the fly ash under anoxic conditions. From the analysis of the PCDD/Fs concentrations in the gas phrase and solid residual, the several kinds of potential chemical reaction and physical changes of dioxin that occur at the different temperature are concluded. At the same time, desorption ratios of 17 toxic dioxin congers and the better desorption conditions are studied. At 200 degrees C and 300 degrees C, the average desorption ratio of PCDD/Fs are 96.2% and 95.5% respectively. At 400 degrees C, the average desorption ratio of PCDD/Fs is 99.7%. The experiment results show that the PCDD/Fs is dechlorinated at 300 degrees C. At 400 degrees C, a lot of precursor reactions happen in the fly ash, which enhance the content of PCDD/Fs.


Assuntos
Poluentes Atmosféricos/química , Carbono/química , Dioxinas/química , Incineração , Material Particulado/química , Adsorção , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/prevenção & controle , Carbono/análise , Cinza de Carvão , Dioxinas/análise , Temperatura Alta , Material Particulado/análise
19.
Rapid Commun Mass Spectrom ; 22(12): 1941-54, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18491284

RESUMO

The mass spectral fragmentation behavior of ten iridoid glucosides (IGs) has been studied using electrospray ionization (ESI), collision-induced dissociation (CID), and quadrupole time-of-flight tandem mass spectrometry (Q-TOF MS/MS). In the negative ESI mass spectra, the deprotonated [M-H](-) ion was observed for all of the ten IGs except gardoside methyl ester, while the formate adduct [M+HCOO](-) ion appeared to be favored by the presence of a methyl ester or a lactone group in the C-4 position when formic acid was added to the mobile phase. The CID MS/MS spectra of the [M-H](-) ions have been used for structural elucidation. Ring cleavages of the aglycone moiety have been observed in the MS/MS spectra, corresponding to (1,4)F(-), (2,6)F(-), (2,7)F(-), and (2,7)F(0) (-) ions, based on accurate mass measurements and the elemental compositions of the product ions. These characteristic ions gave valuable information on the basic structural skeletons. Furthermore, on the basis of the relative abundances of the fragment ions (1,4)F(-) and (2,7)F(-), different sub-classes, such as cyclopentane-type and 7,8-cyclopentene-type IGs, can be differentiated. Ring cleavage of the sugar moieties was also observed, yielding useful information for their characterization. In addition, the neutral losses, such as H(2)O, CO(2), CH(3)OH, CH(3)COOH, and glucosidic units, have proved useful for confirming the presence of functional substituents in the structures of the IGs. Based on the fragmentation patterns of these standard IGs, twelve IGs have been characterized in an extract of Hedyotis diffusa Willd. by means of ultra-performance liquid chromatography/Q-TOF MS/MS, of which six have been unambiguously identified and the other six have been tentatively identified.


Assuntos
Glucosídeos/análise , Iridoides/química , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Glucosídeos/química , Hedyotis/química , Estrutura Molecular
20.
Rapid Commun Mass Spectrom ; 22(8): 1275-87, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18383217

RESUMO

C-Glycosyl quinochalcones are unique components in Carthamus tinctorius L. The reported C-glycosyl quinochalcones have the same quinochalcone skeleton with a hydroxyl group at the 5'-position and a glucose linked to this position with a carbon-carbon bond. In this study, the standard hydroxysafflor yellow A and water-extracted fraction of Carthamus tinctorius L. were analyzed by ultraperformance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UPLC/Q-TOFMS) in both positive and negative ion modes. The fragmentation pathways of C-glycosyl quinochalcones were interpreted and validated by accurate mass measurement. Their fragmentation showed a special cleavage at the C-C bond except for the typical internal cleavage at the sugar moiety of other C-glycosyl flavonoids. In positive ion mode, cleavage of the 5'-glucose produced an [M+H-162](+) ion by a neutral loss, while cleavage of the 5'-glucose in negative ion mode led to an [M-H-163](-.) ion by radical cleavage. The cleavage from the carbonyl group produced fragment ions containing an A or a B ring. The fragment ions containing an A ring were common product ions of seven compounds in both ion modes, and fragment ions containing the B ring were used to judge the different substituent groups at the 3'-position. The fragmentation patterns of seven structurally related C-glycosyl quinochalcones were analyzed systematically and the formation of the fragment ions in two modes is explained in detail in this report. UPLC/Q-TOFMS is an effective tool for characterizing a complex sample, which gives higher resolution separation and generates accurate mass measurement of the product ions.


Assuntos
Carthamus tinctorius/química , Chalcona/análogos & derivados , Glicosídeos/química , Plantas Medicinais/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Chalcona/química , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/química , Glucosídeos/química , Pigmentos Biológicos/química , Extratos Vegetais , Quinonas/química , Reprodutibilidade dos Testes
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