Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
bioRxiv ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38798440

RESUMO

Understanding the distribution of hundreds of thousands of plant metabolites across the plant kingdom presents a challenge. To address this, we curated publicly available LC-MS/MS data from 19,075 plant extracts and developed the plantMASST reference database encompassing 246 botanical families, 1,469 genera, and 2,793 species. This taxonomically focused database facilitates the exploration of plant-derived molecules using tandem mass spectrometry (MS/MS) spectra. This tool will aid in drug discovery, biosynthesis, (chemo)taxonomy, and the evolutionary ecology of herbivore interactions.

2.
Phytochem Anal ; 34(7): 869-883, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37403427

RESUMO

INTRODUCTION: This study describes the molecular profile and the potential antiviral activity of extracts from Phyllanthus brasiliensis, a plant widely found in the Brazilian Amazon. The research aims to shed light on the potential use of this species as a natural antiviral agent. METHODS: The extracts were analysed using liquid chromatography-mass spectrometry (LC-MS) system, a potent analytical technique to discover drug candidates. In the meantime, in vitro antiviral assays were performed against Mayaro, Oropouche, Chikungunya, and Zika viruses. In addition, the antiviral activity of annotated compounds was predicted by in silico methods. RESULTS: Overall, 44 compounds were annotated in this study. The results revealed that P. brasiliensis has a high content of fatty acids, flavones, flavan-3-ols, and lignans. Furthermore, in vitro assays revealed potent antiviral activity against different arboviruses, especially lignan-rich extracts against Zika virus (ZIKV), as follows: methanolic extract from bark (MEB) [effective concentration for 50% of the cells (EC50 ) = 0.80 µg/mL, selectivity index (SI) = 377.59], methanolic extract from the leaf (MEL) (EC50 = 0.84 µg/mL, SI = 297.62), and hydroalcoholic extract from the leaf (HEL) (EC50 = 1.36 µg/mL, SI = 735.29). These results were supported by interesting in silico prediction, where tuberculatin (a lignan) showed a high antiviral activity score. CONCLUSIONS: Phyllanthus brasiliensis extracts contain metabolites that could be a new kick-off point for the discovery of candidates for antiviral drug development, with lignans becoming a promising trend for further virology research.


Assuntos
Lignanas , Phyllanthus , Infecção por Zika virus , Zika virus , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Phyllanthus/química , Antivirais/farmacologia , Lignanas/farmacologia , Lignanas/química
3.
Metabolites ; 12(11)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36355166

RESUMO

Deguelia nitidula (Benth.) A.M.G.Azevedo & R.A.Camargo (Fabaceae) is an herbaceous plant distributed in the Brazilian Amazon, and it is called "raiz do sol" (sun roots). On Marajó Island, quilombola communities use its prepared roots to treat skin diseases commonly caused by fungi, viruses, and bacteria. Thus, in this study, the extract, and its fractions from D. nitidula roots were used to perform in vitro cytotoxic and antibacterial assays against Staphylococcus aureus strains. Thereafter, liquid chromatography-mass spectrometry (LC-MS) was used for the metabolite annotation process. The ethanolic extract of D. nitidula roots show significant bactericidal activity against S. aureus with IC50 82 µg.mL-1 and a selectivity index (SI) of 21.35. Furthermore, the SREFr2 and SREFr3 fractions show a potent bactericidal activity, i.e., MIC of 46.8 µg.mL-1 for both, and MBC of 375 and 93.7 µg.mL-1, respectively. As showcased, SREFr3 shows safe and effective antibacterial activity mainly in respect to the excellent selectivity index (SI = 82.06). On the other hand, SREFr2 shows low selectivity (SI = 6.8), which characterizes it as not safe for therapeutic use. Otherwise, due to a limited amount of reference MS2 spectra in public libraries, up to now, it was not possible to perform a complete metabolite annotation. Despite that, our antibacterial results for SREFr3 and correlated substructures of amino acid derivatives show that the roots of D. nitidula are a natural source of specialized metabolites, which can be isolated in the future, and then used as a support for further bio-guided research, as well as natural drug development.

4.
Molecules ; 25(24)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33352821

RESUMO

The main challenge of plant chemical diversity exploration is how to develop tools to study exhaustively plant tissues. Their sustainable sourcing is a limitation as bioguided strategies and dereplication need quite large amounts of plant material. We examine if alternative solutions could overcome these difficulties by obtaining a secure, sustainable, and scalable source of tissues able to biosynthesize an array of metabolites. As this approach would be as independent of the botanical origin as possible, we chose eight plant species from different families. We applied a four steps culture establishment procedure, monitoring targeted compounds through mass spectrometry-based analytical methods. We also characterized the capacities of leaf explants in culture to produce diverse secondary metabolites. In vitro cultures were successfully established for six species with leaf explants still producing a diversity of compounds after the culture establishment procedure. Furthermore, explants from leaves of axenic plantlets were also analyzed. The detection of marker compounds was confirmed after six days in culture for all tested species. Our results show that the first stage of this approach aiming at easing exploration of plant chemodiversity was completed, and leaf tissues could offer an interesting alternative providing a constant source of natural compounds.


Assuntos
Produtos Biológicos/metabolismo , Folhas de Planta/metabolismo , Plantas/metabolismo , Produtos Biológicos/química , Espectrometria de Massas , Folhas de Planta/química , Plantas/química
5.
PLoS One ; 15(1): e0225514, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929529

RESUMO

Based on ethnopharmacological studies, a lot of plants, as well as its compounds, have been investigated for the potential use as wound healing agents. In Brazil, Curatella americana is traditionally used by local people to treat wounds, ulcers and inflammations. However, to the best of our knowledge, its traditional use in the treatment of wounds has not been validated by a scientific study. Here, some compounds, many of them flavonoids, were identified in the hydroethanolic extract from the leaves of C. americana (HECA) by LC-HRMS and LC-MS/MS. Besides that, solutions containing different concentrations of HECA and a gel produced with this extract were evaluated for its antimicrobial, coagulant and wound healing activities on an excision mouse wound model as well as its acute dermal safety. A total of thirteen compounds were identified in HECA, mainly quercetin, kaempferol and glucoside derivatives of both, besides catechin and epicatechin known as wound healing agents. The group treated with 1% of HECA exhibited highest wound healing activity and best rate of wound contraction confirmed by histopathology results. The present study provides scientific evidence of, this extract (HECA) possess remarkable wound healing activity, thereby, supporting the traditional use.


Assuntos
Dilleniaceae/química , Extratos Vegetais/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Brasil , Catequina/isolamento & purificação , Cromatografia Líquida , Flavonoides/química , Flavonoides/farmacologia , Glucosídeos/química , Glucosídeos/isolamento & purificação , Humanos , Quempferóis/química , Quempferóis/isolamento & purificação , Camundongos , Extratos Vegetais/química , Folhas de Planta/química , Quercetina/química , Quercetina/isolamento & purificação , Espectrometria de Massas em Tandem
6.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-115239

RESUMO

OBJECTIVE: To identify suitable diagnostic tools and evaluate the efficacy of sentinel lymph node (SLN) biopsy for inguinal lymph node metastasis in vulvar cancer. METHODS: Data from 41 patients with vulvar cancer were evaluated retrospectively, including magnetic resonance imaging (MRI) measurements, SLN biopsy status, groin lymph node metastasis, and prognosis. RESULTS: SLN biopsy was conducted in 12 patients who had stage I to III disease. Groin lymphadenectomy was omitted in five of the nine patients with negative SLNs. All SLN-negative patients who did not undergo groin lymphadenectomy showed no evidence of disease after treatment. On MRI, the long and short diameters of the inguinal node were significantly longer in metastasis-positive cases, compared with negative cases, in 25 patients whose nodes were evaluated pathologically (long diameter, 12.8 mm vs. 8.8 mm, p=0.025; short diameter, 9.2 mm vs. 6.7 mm, p=0.041). The threshold of >10.0 mm for the long axis gave a sensitivity, specificity, positive predictive value, and negative predictive value of 87.5%, 70.6%, 58.3%, and 92.3%, respectively, using a binary classification test. Decision tree analysis revealed a sensitivity, specificity, and accuracy of 87.5%, 70.6%, and 76.0%, respectively, with the threshold of >10.0 mm for the long axis on MRI. The criteria of >10.0 mm for the long axis on MRI predicted an advanced stage and poorer prognosis using a validation set of 15 cases (p=0.028). CONCLUSION: Minimally invasive surgery after preoperative evaluation on MRI and SLN biopsy is a feasible strategy for patients with vulvar cancer.


Assuntos
Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Virilha , Excisão de Linfonodo , Metástase Linfática/patologia , Imageamento por Ressonância Magnética , Prognóstico , Estudos Retrospectivos , Sensibilidade e Especificidade , Linfonodo Sentinela/patologia , Biópsia de Linfonodo Sentinela/métodos , Neoplasias Vulvares/patologia
7.
Psychol. neurosci. (Impr.) ; 6(2): 145-150, jul.-dez. 2013. tab
Artigo em Inglês | LILACS | ID: lil-699231

RESUMO

The neural retina is a highly complex tissue composed of excitatory and inhibitory neurons and glial cells. Glutamate, the main excitatory neurotransmitter, mediates information transfer from photoreceptors, bipolar cells, and ganglion cells, whereas interneurons, mainly amacrine and horizontal cells, use γ-aminobutyric acid (GABA), the main inhibitory neurotransmitter. In this review we place an emphasis on glutamate and GABA transporters as highly regulated molecules that play fundamental roles in neurotransmitter clearance, neurotransmitter release, and oxidative stress. We pharmacologically characterized glutamate transporters in chicken retina cells and identified two glutamate transporters: one Na+-dependent transporter and one Na+-independent transporter. The Na+-dependent uptake system presented characteristics related to the high-affinity xAG- system (EAAT1), and the Na+-independent uptake system presented characteristics related to the xCG- system, which highly contributes to glutamate transport in the retina. Glutamate shares the xCG- system with another amino acid, L-cysteine, suggesting the possible involvement of glutathione. Both transporter proteins are present mainly in Müller glial cells. GABA transporters (GATs) mediate high-affinity GABA uptake from the extracellular space and terminate the synaptic action of GABA in the central nervous system. GABA transporters can be modulated by molecules that act on specific sites to promote transporter phosphorylation and dephosphorylation. In addition to a role in the clearance of GABA, GATs may also release GABA through a reverse transport mechanism. In the chicken retina, a GAT-1 blocker, but not GAT2/3 blocker, was shown to inhibit GABA uptake, suggesting that GABA release from retina cells is mainly mediated by a GAT-1-like transporter.


Assuntos
Ácido gama-Aminobutírico , Ácido Glutâmico , Retina
8.
Psychol. neurosci. (Impr.) ; 6(2): 145-150, 2013. tab
Artigo em Inglês | Index Psicologia - Periódicos | ID: psi-61343

RESUMO

The neural retina is a highly complex tissue composed of excitatory and inhibitory neurons and glial cells. Glutamate, the main excitatory neurotransmitter, mediates information transfer from photoreceptors, bipolar cells, and ganglion cells, whereas interneurons, mainly amacrine and horizontal cells, use γ-aminobutyric acid (GABA), the main inhibitory neurotransmitter. In this review we place an emphasis on glutamate and GABA transporters as highly regulated molecules that play fundamental roles in neurotransmitter clearance, neurotransmitter release, and oxidative stress. We pharmacologically characterized glutamate transporters in chicken retina cells and identified two glutamate transporters: one Na+-dependent transporter and one Na+-independent transporter. The Na+-dependent uptake system presented characteristics related to the high-affinity xAG- system (EAAT1), and the Na+-independent uptake system presented characteristics related to the xCG- system, which highly contributes to glutamate transport in the retina. Glutamate shares the xCG- system with another amino acid, L-cysteine, suggesting the possible involvement of glutathione. Both transporter proteins are present mainly in Müller glial cells. GABA transporters (GATs) mediate high-affinity GABA uptake from the extracellular space and terminate the synaptic action of GABA in the central nervous system. GABA transporters can be modulated by molecules that act on specific sites to promote transporter phosphorylation and dephosphorylation. In addition to a role in the clearance of GABA, GATs may also release GABA through a reverse transport mechanism. In the chicken retina, a GAT-1 blocker, but not GAT2/3 blocker, was shown to inhibit GABA uptake, suggesting that GABA release from retina cells is mainly mediated by a GAT-1-like transporter.(AU)


Assuntos
Ácido gama-Aminobutírico , Ácido Glutâmico , Retina
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...