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1.
Org Lett ; 26(1): 274-279, 2024 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-38134219

RESUMO

Chemical investigation of the emblematic Catharanthus roseus led to the discovery of trirosaline (1), the first example of a tris-ajmalicine-type monoterpene indole alkaloid and the first natural trimeric MIA ever reported from this deeply dug plant species. Its structure was primarily elucidated based on NMR and HRESIMS analyses, and the nature of its unique intermonomeric linkages was firmly confirmed based on a combination of empirical computation and ML-J-DP4 study. Its absolute configuration was mitigated by comparison of experimental and TDDFT-simulated electronic circular dichroism (ECD) spectra. A possible biosynthetic pathway for trirosaline (1) was postulated.


Assuntos
Catharanthus , Alcaloides de Triptamina e Secologanina , Monoterpenos , Catharanthus/química , Catharanthus/metabolismo , Alcaloides Indólicos/química , Aprendizado de Máquina , Proteínas de Plantas/química
2.
Bioorg Chem ; 141: 106859, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37742494

RESUMO

A bio-assay guided fractionation strategy based on cholinesterase assay combined with 13C NMR-based dereplication was used to identify active metabolites from the bark of Mesua lepidota. Eight compounds were identified with the aid of the 13C NMR-based dereplication software, MixONat, i.e., sitosterol (1), stigmasterol (2), α-amyrin (3), friedelin (6), 3ß-friedelinol (7), betulinic acid (9), lepidotol A (10) and lepidotol B (11). Further bio-assay guided isolation of active compounds afforded one xanthone, pyranojacareubin (12) and six coumarins; lepidotol A (10), lepidotol B (11), lepidotol E (13), lepidotin A (14), and lepidotin B (15), including a new Mammea coumarin, lepidotin C (16). All the metabolites showed strong to moderate butyrylcholinesterase (BChE) inhibition. Lepidotin B (15) exhibited the most potent inhibition towards BChE with a mix-mode inhibition profile and a Ki value of 1.03 µM. Molecular docking and molecular dynamics simulations have revealed that lepidotin B (15) forms stable interactions with key residues within five critical regions of BChE. These regions encompass residues Asp70 and Tyr332, the acyl hydrophobic pocket marked by Leu286, the catalytic triad represented by Ser198 and His438, the oxyanion hole (OH) constituted by Gly116 and Gly117, and the choline binding site featuring Trp82. To gauge the binding strength of lepidotin B (15) and to pinpoint pivotal residues at the binding interface, free energy calculations were conducted using the Molecular Mechanics Generalized Born Surface Area (MM-GBSA) approach. This analysis not only predicted a favourable binding affinity for lepidotin B (15) but also facilitated the identification of significant residues crucial for the binding interaction.


Assuntos
Butirilcolinesterase , Inibidores da Colinesterase , Inibidores da Colinesterase/química , Butirilcolinesterase/metabolismo , Simulação de Acoplamento Molecular , Casca de Planta/química , Software , Acetilcolinesterase/metabolismo
3.
Phytochem Anal ; 34(4): 461-475, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37051779

RESUMO

INTRODUCTION: Propolis is a resinous natural substance collected by honeybees from buds and exudates of various trees and plants; it is widely accepted that the composition of propolis depends on the phytogeographic characteristics of the site of collection. OBJECTIVES: The aim of this study was to determine the phytochemical composition of ethanolic extracts from eight propolis batches collected in different regions of Benin (north, center, and south) and Congo, Africa. MATERIAL AND METHODS: Characterization of propolis samples was performed by using different hyphenated chromatographic methods combined with carbon-13 nuclear magnetic resonance (13 C NMR) dereplication with MixONat software. Their antioxidant or anti-advanced glycation end-product (anti-AGE) activity was then evaluated by using diphenylpicrylhydrazyl and bovine serum albumin assays, respectively. RESULTS: Chromatographic analyses combined with 13 C NMR dereplication showed that two samples from the center of Benin exhibited, in addition to a huge amount of pentacyclic triterpenes, methoxylated stilbenoids or phenanthrenoids, responsible for the antioxidant activity of the extract for the first one. Among them, combretastatins might be cytotoxic. For the second one, the prenylated flavanones known in Macaranga-type propolis were responsible for its significant anti-AGE activity. The sample from Congo was composed of many triterpene derivatives belonging to Mangifera indica species. CONCLUSION: Therefore, propolis from the center of Benin seems to be of particular interest, due to its antioxidant and anti-AGE properties. Nevertheless, as standardization of propolis is difficult in tropical zones due to its great chemodiversity, a systematic phytochemical analysis is required before promoting the use of propolis in food and health products in Africa.


Assuntos
Própole , Animais , Própole/química , Antioxidantes/química , Congo , Benin , Espectroscopia de Ressonância Magnética , Compostos Fitoquímicos
4.
Cancers (Basel) ; 14(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36551648

RESUMO

Breast cancer (BC) occurs less frequently in Asia, where there is high soy consumption. It has been hypothesized that soy isoflavones could be protective against BC recurrence and mortality. At the same time, health organizations in several countries have differing recommendations for soy consumption (soy foods or dietary supplements) in BC survivors. The objective of this review is to analyze the literature and to determine whether it is justified to advise avoiding soy in dietary supplements and/or food in women with a history of BC. We conducted a systematic literature search with the Medline/Pubmed and Web of Science databases. Only prospective cohort studies published since 2009 were retained. The endpoint of studies was BC recurrence and/or mortality, and the association with soy isoflavone intake was specifically targeted. Seven studies were included. None of these studies found statistically significant adverse effects of soy consumption on BC recurrence or mortality (specific or all-cause). Overall, only one study was not able to find beneficial effects of soy intake on BC patients. The other studies concluded that there were positive associations but in very variable ways. Two studies found a decrease in BC recurrence associated with a higher isoflavone intake only for post-menopausal women. The other four studies concluded that there were positive associations regardless of menopausal status. Four studies showed better results on women with hormonal-sensitive cancer and/or patients receiving hormonal treatment. Only one found a stronger association for patients with ER-negative BC. No adverse effects of soy isoflavones on BC mortality/recurrence were found. Soy isoflavones may exert beneficial effects. These results coincide with other recent works and suggest that soy isoflavone intake is safe for BC survivors. Thus, these data no longer seem to coincide with the French recommendations, which could then be brought to evolve. However, in order to confirm the current results, larger studies are needed.

5.
Nat Prod Res ; : 1-10, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36214555

RESUMO

Presently it is estimated that many of the approximately 4000 new natural products isolated every year following complicated, long, and expensive isolation processes are already known; because of this, developing new strategies for locating secondary metabolites of interest in complex extracts or fractions is important. Currently, chromatographic and spectroscopic techniques are being used to optimize the isolation and identification of natural products. In this investigation we have used 13C NMR dereplication analyses for the quick identification of a number of triterpenes (friedelin, lupeol, betulinic acid), sterols (euphol, ß-sitosterol) and fatty acids (palmitic acid) present in semipurified fractions obtained from the stem bark extract of Clusia flava and to assist in the isolation of the bioactive metabolites trapezifolixanthone and paralycolin A. The complete and correct assignment of the 1H and 13C NMR spectroscopic data for paralycolin A is reported for the first time and the antioxidant and antiAGEs activity of both metabolites is described.

6.
Phytochemistry ; 202: 113300, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35798090

RESUMO

Thirty-three natural products were isolated from the aerial parts of Antidesma bunius, Euphorbiaceae, a plant used in Vietnamese traditional medicine against rheumatoid arthritis. All compounds were reported the first time for this species, and nine constituents resembled undescribed natural products, noticeably three coumarinolignans with 2,2-dimethyl-1,3-dioxolane moiety, two cyclopeptides, and two furofuran-type lignans connected with a phenylpropanoid moiety. The individual structures were elucidated by combining NMR and MS data, and their configuration was established by NOESY and ECD experiments and NMR calculations. Compounds with sufficient amount were analyzed for their inhibition of advanced glycation endproducts (AGEs) formation, metabolites involved in many diseases like Alzheimer, joint diseases or diabetes. With IC50 values below 0.2 mM rutin and p-hydroxyphenethyl trans-ferulate showed to be moderately active, both still being 10-times more active than the positive control aminoguanidine.


Assuntos
Produtos Biológicos , Euphorbiaceae , Euphorbiaceae/química , Produtos Finais de Glicação Avançada , Componentes Aéreos da Planta , Vietnã
7.
Phytochem Anal ; 32(6): 1102-1109, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33938065

RESUMO

INTRODUCTION: Xanthones are metabolites with a variety of biological properties. The Clusiaceae family, which until recently included the genus Calophyllum, is recognised for its production of monohydroxylated and polyhydroxylated xanthones. Presently, C. brasiliense is the only Calophyllum spp. known to occur in the Yucatan peninsula. OBJECTIVE: To use a combination of traditional phytochemical methods and carbon-13 nuclear magnetic resonance (13 C-NMR) dereplication analysis to identify xanthones in the stem bark of C. brasiliense. MATERIAL AND METHODS: Initial fractionation and purification of the stem bark extract of C. brasiliense produced macluraxanthone (1). Additional xanthones, together with chromanones and terpenoids, were identified using 13 C-NMR dereplication analysis in different semipurified fractions obtained from the low and medium polarity fractions of the stem bark extract of C. brasiliense. RESULTS: Initial identification of macluraxanthone (1) was confirmed by 13 C-NMR dereplication analysis; additionally, 13 C-NMR dereplication analysis allowed the identification of a number of monohydroxylated and polyhydroxylated xanthones, together with chromanones and terpenoids. CONCLUSION: This study confirms C. brasiliense as a rich source of xanthones and the 13 C-NMR dereplication analysis as a suitable method to quickly identify the presence of different families of secondary metabolites in semipurified fractions.


Assuntos
Calophyllum , Xantonas , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Casca de Planta , Extratos Vegetais
8.
Planta Med ; 87(12-13): 1061-1068, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33957699

RESUMO

The growing use of herbal medicines worldwide requires ensuring their quality, safety, and efficiency to consumers and patients. Quality controls of vegetal extracts are usually undertaken according to pharmacopeial monographs. Analyses may range from simple chemical experiments to more sophisticated but more accurate methods. Nowadays, metabolomic analyses allow a fast characterization of complex mixtures. In the field, besides mass spectrometry (MS), nuclear magnetic resonance spectroscopy (NMR) has gained importance in the direct identification of natural products in complex herbal extracts. For a decade, automated dereplication processes based on 13C-NMR have been emerging to efficiently identify known major compounds in mixtures. Though less sensitive than MS, 13C-NMR has the advantage of being appropriate to discriminate stereoisomers. Since NMR spectrometers nowadays provide useful datasets in a reasonable time frame, we have recently made available MixONat, a software that processes 13C as well as distortionless enhancement by polarization transfer (DEPT)-135 and -90 data, allowing carbon multiplicity (i.e., CH3, CH2, CH, and C) filtering as a critical step. MixONat requires experimental or predicted chemical shifts (δ C) databases and displays interactive results that can be refined based on the user's phytochemical knowledge. The present article provides step-by-step instructions to use MixONat starting from database creation with freely available and/or marketed δ C datasets. Then, for training purposes, the reader is led through a 30 - 60 min procedure consisting of the 13C-NMR based dereplication of a peppermint essential oil.


Assuntos
Produtos Biológicos , Produtos Biológicos/análise , Isótopos de Carbono , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Humanos , Software
9.
Biomolecules ; 10(9)2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887413

RESUMO

Modulation of major histocompatibility complex (MHC) expression using drugs has been proposed to control immunity. Phytochemical investigations on Garcinia species have allowed the isolation of bioactive compounds such as polycyclic polyprenylated acylphloroglucinols (PPAPs). PPAPs such as guttiferone J (1), display anti-inflammatory and immunoregulatory activities while garcinol (4) is a histone acetyltransferases (HAT) p300 inhibitor. This study reports on the isolation, identification and biological characterization of two other PPAPs, i.e., xanthochymol (2) and guttiferone F (3) from Garcinia bancana, sharing structural analogy with guttiferone J (1) and garcinol (4). We show that PPAPs 1-4 efficiently downregulated the expression of several MHC molecules (HLA-class I, -class II, MICA/B and HLA-E) at the surface of human primary endothelial cells upon inflammation. Mechanistically, PPAPs 1-4 reduce MHC proteins by decreasing the expression and phosphorylation of the transcription factor STAT1 involved in MHC upregulation mediated by IFN-γ. Loss of STAT1 activity results from inhibition of HAT CBP/p300 activity reflected by a hypoacetylation state. The binding interactions to p300 were confirmed through molecular docking. Loss of STAT1 impairs the expression of CIITA and GATA2 but also TAP1 and Tapasin required for peptide loading and transport of MHC. Overall, we identified new PPAPs issued from Garcinia bancana with potential immunoregulatory properties.


Assuntos
Garcinia/química , Floroglucinol/análogos & derivados , Floroglucinol/farmacologia , Compostos Policíclicos/farmacologia , Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/metabolismo , Acilação , Benzofenonas/química , Benzofenonas/isolamento & purificação , Benzofenonas/farmacologia , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Fator de Transcrição GATA2/metabolismo , Humanos , Interferon gama/metabolismo , Complexo Principal de Histocompatibilidade/efeitos dos fármacos , Complexo Principal de Histocompatibilidade/genética , Proteínas de Membrana Transportadoras/metabolismo , Simulação de Acoplamento Molecular , Proteínas Nucleares/metabolismo , Floroglucinol/química , Floroglucinol/isolamento & purificação , Compostos Policíclicos/química , Compostos Policíclicos/isolamento & purificação , Prenilação , Cultura Primária de Células , Fator de Transcrição STAT1/metabolismo , Terpenos/química , Terpenos/farmacologia , Transativadores/metabolismo , Fatores de Transcrição de p300-CBP/antagonistas & inibidores , Fatores de Transcrição de p300-CBP/química
10.
Anal Chem ; 92(13): 8793-8801, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32479074

RESUMO

Whether chemists or biologists, researchers dealing with metabolomics require tools to decipher complex mixtures. As a part of metabolomics and initially dedicated to identifying bioactive natural products, dereplication aims at reducing the usual time-consuming process of known compounds isolation. Mass spectrometry and nuclear magnetic resonance are the most commonly reported analytical tools during dereplication analysis. Though it has low sensitivity, 13C NMR has many advantages for such a study. Notably, it is nonspecific allowing simultaneous high-resolution analysis of any organic compounds including stereoisomers. Since NMR spectrometers nowadays provide useful data sets in a reasonable time frame, we have embarked upon writing software dedicated to 13C NMR dereplication. The present study describes the development of a freely distributed algorithm, namely MixONat and its ability to help researchers decipher complex mixtures. Based on Python 3.5, MixONat analyses a {1H}-13C NMR spectrum optionally combined with DEPT-135 and 90 data-to distinguish carbon types (i.e., CH3, CH2, CH, and C)-as well as a MW filtering. The software requires predicted or experimental carbon chemical shifts (δc) databases and displays results that can be refined based on user interactions. As a proof of concept, this 13C NMR dereplication strategy was evaluated on mixtures of increasing complexity and exhibiting pharmaceutical (poppy alkaloids), nutritional (rosemary extracts) or cosmetics (mangosteen peel extract) applications. Associated results were compared with other methods commonly used for dereplication. MixONat gave coherent results that rapidly oriented the user toward the correct structural types of secondary metabolites, allowing the user to distinguish between structurally close natural products, including stereoisomers.


Assuntos
Produtos Biológicos/química , Espectroscopia de Ressonância Magnética/métodos , Software , Algoritmos , Alcaloides/química , Isótopos de Carbono/química , Bases de Dados de Compostos Químicos , Garcinia mangostana/química , Garcinia mangostana/metabolismo , Papaver/química , Papaver/metabolismo , Extratos Vegetais/química , Rosmarinus/química , Rosmarinus/metabolismo
11.
Nat Prod Res ; 33(15): 2182-2191, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30375240

RESUMO

Alkaloids and phenolic compounds are among the most biologically active natural products from the Jacobaea/Senecio genera (Asteraceae). To isolate original natural products directly from Jacobaea gigantea crude polar extracts, centrifugal partition chromatography (CPC) was used. Previously, we reported the phytochemical study of J. gigantea (syn. Senecio giganteus) n-butanol extract using various classical chromatographical techniques combined with CPC. Herein major constituents from the J. gigantea crude ethyl acetate extract and further compounds from the n-butanol extract were purified in only one step using this technique. A new pyrrolidine alkaloid, named senecipyrrolidine was isolated along with thirteen known compounds - chiro-inositol, three phenolic acids, six flavonoids, two quinones and emiline, another pyrrolidine alkaloid - from crude n-butanol or ethyl acetate extracts. Pyrrolidine alkaloids were isolated for the first time in the Jacobaea/Senecio genera and were probably biogenetically related to the two isolated quinones derivatives jacaranone and 3a-hydroxy-3,3a,7,7a-tetrahydrobenzofuran-2,6-dione, isolated in this species.


Assuntos
Alcaloides/isolamento & purificação , Extratos Vegetais/química , Pirrolidinas/isolamento & purificação , Senécio/química , Alcaloides/química , Pirrolidinas/química , Análise Espectral/métodos
12.
Mar Drugs ; 18(1)2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31906052

RESUMO

Mycosporine-like amino acids (MAAs) are water-soluble metabolites, reported to exhibit strong UV-absorbing properties. They have been found in a wide range of marine organisms, especially those that are exposed to extreme levels of sunlight, to protect them against solar radiation. In the present study, the absolute configuration of 14 mycosporine-like-amino acids was determined by combining the results of electronic circular dichroism (ECD) experiments and that of advanced Marfey's method using LC-MS. The crystal structure of a shinorine hydrate was determined from single crystal X-ray diffraction data and its absolute configuration was established from anomalous-dispersion effects. Furthermore, the anti-aging and wound-healing properties of these metabolites were evaluated in three different assays namely the inhibition of collagenase, inhibition of advanced glycation end products (AGEs) and wound healing assay (scratch assay).


Assuntos
Aminoácidos/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Aminoácidos/química , Dicroísmo Circular , Colagenases/efeitos dos fármacos , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Humanos , Técnicas In Vitro , Difração de Raios X
13.
Fitoterapia ; 131: 59-64, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30321650

RESUMO

Usually isolated from Garcinia (Clusiaceae) or Hypericum (Hypericaceae) species, some Polycyclic Polyprenylated AcylPhloroglucinols (PPAPs) have been recently reported as potential research tools for immunotherapy. Aiming at exploring the chemodiversity of PPAPs amongst Garcinia genus, a dereplication process suitable for such natural compounds has been developed. Although less sensitive than mass spectrometry, NMR spectroscopy is perfectly reproducible and allows stereoisomers distinction, justifying the development of 13C-NMR strategies. Dereplication requires the use of databases (DBs). To define if predicted DBs were accurate enough as dereplication tools, experimental and predicted δC of natural products usually isolated from Clusiaceae were compared. The ACD/Labs commercial software allowed to predict 73% of δC in a 1.25 ppm range around the experimental values. Consequently, with these parameters, the major PPAPs from a Garcinia bancana extract were successfully identified using a predicted DB.


Assuntos
Garcinia/química , Floroglucinol/isolamento & purificação , Extratos Vegetais/química , Bases de Dados de Compostos Químicos , Espectroscopia de Ressonância Magnética , Compostos Fitoquímicos/isolamento & purificação
14.
Fitoterapia ; 131: 182-188, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30339926

RESUMO

Secondary metabolites from lichens are known for exhibiting various biological effects such as anti-inflammatory, antioxidant and antibacterial activities. Despite this wide range of reported biological effects, their impact on the formation of advanced glycation end products (AGEs) remains vastly unexplored. The latter are known contributors to lifestyle and age-related diseases such as Alzheimer and Parkinson. Moreover, the development of atherosclerosis and arterial stiffness is causally linked to the formation of AGEs. With this in mind, the present work evaluated the inhibitory effects of secondary lichen metabolites on the formation of pentosidine-like AGEs' by using an in vitro, Maillard reaction based, fluorescence assay. Overall, thirty-seven natural and five synthetically modified compounds were tested, eighteen of which exhibiting IC50 values in the range of 0.05 to 0.70 mM. This corresponds to 2 to 32 fold of the inhibitory activity of aminoguanidine. Targeting one major inhibiting mechanism of AGEs formation, all compounds were additionally evaluated on their radical scavenging capacities in an DPPH assay. Furthermore, as both AGEs' formation and hypertension are major risk factors for atherosclerosis, compounds that were available in sufficient amounts were also tested for their vasodilative effects. Overall, and though some of the active compounds were previously reported cytotoxic, present results highlight the interesting potential of secondary lichen metabolites as anti-AGEs and vasodilative agents.


Assuntos
Produtos Biológicos/farmacologia , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Líquens/química , Vasodilatadores/farmacologia , Animais , Produtos Biológicos/isolamento & purificação , Masculino , Estrutura Molecular , Ratos Endogâmicos WKY , Metabolismo Secundário , Vasodilatadores/isolamento & purificação
15.
J Nat Prod ; 81(8): 1850-1859, 2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-30024167

RESUMO

Phytochemical investigation of the root extracts of Hypericum perforatum led to the isolation of two biphenyl derivatives named hyperbiphenyls A and B (1 and 2) and four known xanthones (3-6). These structures were elucidated by spectroscopic and spectrometric methods including UV, NMR, and HRMS. The absolute configuration of the biphenyl derivatives was defined by two different approaches: biomimetic total synthesis of racemic hyperbiphenyl A followed by 1H and 19F NMR Mosher's esters analysis and stereoselective total synthesis of hyperbiphenyl B, permitting assignment of the S absolute configuration for both compounds. The bioactivity of compounds 1-6 toward a set of biomolecules, including major histocompatibility complex (MHC) molecules expressed on vascular endothelial cells, was measured. The results showed that the major xanthone, i.e., 5- O-methyl-2-deprenylrheediaxanthone B (3), is a potent inhibitor of MHC that efficiently reduces HLA-E, MHC-II, and MICA biomolecules on cell surfaces.


Assuntos
Benzofuranos/química , Benzofuranos/farmacologia , Benzopiranos/química , Benzopiranos/farmacologia , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacologia , Hypericum/química , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Raízes de Plantas/química , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Fatores Imunológicos/síntese química , Espectroscopia de Ressonância Magnética , Ressonância Magnética Nuclear Biomolecular , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta , Estereoisomerismo
16.
Nat Prod Res ; 31(19): 2286-2293, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28475369

RESUMO

Chemical investigation of the leaves of Bupleurum lancifolium led to the isolation and identification of two triterpenoid saponins previously undescribed named 3-O-[α-L-rhamnopyranosyl (1 â†’ 4)-ß-D-glucopyranosyl] echinocystic acid 28-O-ß-D-glucopyranosyl ester (1) and 3-O-[α-L-rhamnopyranosyl (1 â†’ 4)-ß-D-glucopyranosyl] oleanolic acid 28-O-ß-D-glucopyranosyl ester (2) along with the two known compounds isorhamnetin 3-rutinoside (3) and rutin (4). Their structures were elucidated by different spectroscopic methods, including HRESIMS analysis as well as 1D and 2D NMR experiments.


Assuntos
Apiaceae/química , Bupleurum/química , Folhas de Planta/química , Saponinas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Ácido Oleanólico/análogos & derivados , Saponinas/química , Análise Espectral , Triterpenos/química , Triterpenos/isolamento & purificação
17.
PLoS One ; 11(12): e0167361, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27907087

RESUMO

Endothelial cells (ECs) are key players in inflammation and immune responses involved in numerous pathologies. Although attempts were experimentally undertaken to prevent and control EC activation, drug leads and probes still remain necessary. Natural products (NPs) from Clusiaceous and Calophyllaceous plants were previously reported as potential candidates to prevent endothelial dysfunction. The present study aimed to identify more precisely the molecular scaffolds that could limit EC activation. Here, 13 polyphenols belonging to 5 different chemical types of secondary metabolites (i.e., mammea coumarins, a biflavonoid, a pyranochromanone acid, a polyprenylated polycyclic acylphloroglucinol (PPAP) and two xanthones) were tested on resting and cytokine-activated EC cultures. Quantitative and qualitative changes in the expression of both adhesion molecules (VCAM-1, ICAM-1, E-selectin) and major histocompatibility complex (MHC) molecules have been used to measure their pharmaceutical potential. As a result, we identified 3 mammea coumarins that efficiently reduce (up to >90% at 10 µM) both basal and cytokine-regulated levels of MHC class I, class II, MICA and HLA-E on EC surface. They also prevented VCAM-1 induction upon inflammation. From a structural point of view, our results associate the loss of the free prenyl group substituting mammea coumarins with a reduced cellular cytotoxicity but also an abrogation of their anti-inflammatory potential and a reduction of their immunosuppressive effects. A PPAP, guttiferone J, also triggers a strong immunomodulation but restricted to HLA-E and MHC class II molecules. In conclusion, mammea coumarins with a free prenyl group and the PPAP guttiferone J emerge as NPs able to drastically decrease both VCAM-1 and a set of MHC molecules and to potentially reduce the immunogenicity of the endothelium.


Assuntos
Produtos Biológicos/farmacologia , Células Endoteliais/efeitos dos fármacos , Inflamação/tratamento farmacológico , Polifenóis/farmacologia , Apresentação de Antígeno/efeitos dos fármacos , Produtos Biológicos/química , Clusiaceae/química , Cumarínicos/farmacologia , Citocinas/biossíntese , Selectina E/biossíntese , Células Endoteliais/patologia , Antígenos de Histocompatibilidade Classe II/biossíntese , Humanos , Inflamação/genética , Inflamação/patologia , Molécula 1 de Adesão Intercelular/biossíntese , Interferon gama/biossíntese , Polifenóis/química , Prenilação/efeitos dos fármacos , Fator de Necrose Tumoral alfa/biossíntese , Molécula 1 de Adesão de Célula Vascular/biossíntese
18.
Pharmacognosy Res ; 8(4): 276-280, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27695268

RESUMO

BACKGROUND: Formation and accumulation of advanced glycation end-products (AGE) is recognized as a major pathogenic process in diabetic complications, atherosclerosis and cardiovascular diseases. In addition, reactive oxygen species and free radicals have also been reported to participate in AGE formation and in cell damage. Natural products with antioxidant and antiAGE activity have great therapeutic potential in the treatment of diabetes, hypertension and related complications. Objective: to test ethanolic extracts and aqueous-traditional preparations of plants used to treat diabetes, hypertension and obesity in Yucatecan traditional medicine for their anti-AGE and free radical scavenging activities. MATERIALS AND METHODS: ethanolic extracts of leaves, stems and roots of nine medicinal plants, together with their traditional preparations, were prepared and tested for their anti-AGE and antioxidant activities using the inhibition of advanced glycation end products and DPPH radical scavenging assays, respectively. RESULTS: the root extract of C. fistula (IC50= 0.1 mg/mL) and the leaf extract of P. auritum (IC50= 0.35 mg/mL) presented significant activity against vesperlysine and pentosidine-like AGE. Although none of the aqueous traditional preparations showed significant activity in the anti-AGE assay, both the traditional preparations and the ethanolic extracts of E. tinifolia, M. zapota, O. campechianum and P. auritum showed significant activity in the DPPH reduction assay. CONCLUSIONS: the results suggest that the metabolites responsible for the detected radical-scavenging activity are different to those involved in inhibiting AGE formation; however, the extracts with antioxidant activity may contain other metabolites which are able to prevent AGE formation through a different mechanism. SUMMARY: Ethanolic extracts from nine plants used to treat diabetes, hypertension and obesity in Yucatecan traditional medicine were tested for their anti-AGE and free radical scavenging activities.Significant activity against vesperlysine and pentosidine-like AGE was detected in the root extract of Cassia fistula and the leaf extract of Piper auritum.Traditional preparations and the ethanolic extracts of Ehretia tinifolia, Manilkara zapota, Ocimum campechianum and Piper auritum showed significant activity in the DPPH reduction assay.Results suggest that the metabolites responsible for the detected radical-scavenging activity are different to those involved in inhibiting AGE formation. Abbreviations Used: AGE: Advanced glycation end-product; DPPH: 2,2-Diphenyl-1-picrylhydrazyl; DM: Diabetes mellitus; ROS: Reactive oxygen species; BSA: Bovine serum albumin; EtOH: Ethanol; EtOAc: Ethyl acetate; ANOVA: Analysis of variance; BA: Brosimum alicastrum; BS: Bunchosia swartziana; CF: Cassia fistula; CN: Cocos nucifera; ET: Ehretia tinifolia; MZ: Manilkara zapota; OC: Ocimum campechianum; PA: Piper auritum; RM: Rhizophora mangle; L: Leaves; S: Stems; R: Roots; T: traditional preparation; I: Inflorescences; W: Water.

19.
Am J Hypertens ; 29(7): 873-81, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26864583

RESUMO

BACKGROUND: Hypertension is characterized by a maintained high blood pressure leading to cardiac complications such as left ventricular hypertrophy and fibrosis and an increased risk of heart failure and myocardial infarction. This study investigated the cardiac effects of oral administration of Moringa oleifera (MOI) seed powder in spontaneous hypertensive rats (SHR). METHODS: SHR received food containing MOI seed powder (750mg/d, 8 weeks) or normal food. In vivo measurement of hemodynamic parameters by telemetry and cardiac structure and function analysis by echocardiography were performed. Histological studies were performed to determine fibrosis and protein expression. RESULTS: MOI treatment did not modify blood pressure in SHR but reduced nocturnal heart rate and improved cardiac diastolic function (reduction of isovolumetric relaxation time and deceleration time of the E wave, increase of ejection volume and cardiac output compared to nontreated SHR). Left ventricular anterior wall thickness, interseptal thickness on diastole, and relative wall thickness were reduced after MOI treatment. Furthermore, we found a significant reduction of fibrosis in the left ventricle of MOI-treated SHR. This antihypertrophic and antifibrotic effect of MOI was associated with increased expression of peroxisome proliferator-activated receptor (PPAR)-α and δ, reduced cardiac triglyceride level, and enhanced plasmatic prostacyclins. CONCLUSIONS: Our data show a beneficial effect of MOI on the cardiac structure and function in SHR associated with an upregulation of PPAR-α and δ signaling. This study thus provides scientific rational support for the empirical use of MOI in the traditional Malagasy medicine against cardiac diseases associated with blood pressure overload.


Assuntos
Cardiopatias/prevenção & controle , Hipertensão/complicações , Moringa oleifera , Fitoterapia , Preparações de Plantas/uso terapêutico , Animais , Pressão Sanguínea , Ecocardiografia , Cardiopatias/etiologia , Frequência Cardíaca , Metabolismo dos Lipídeos , Masculino , Miocárdio/metabolismo , PPAR alfa/metabolismo , PPAR delta/metabolismo , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Sementes
20.
Molecules ; 20(10): 17735-46, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26404214

RESUMO

Through dereplication analysis, seven known Mammea coumarins were identified in a fraction obtained from Mammea neurophylla dichloromethane bark extract selected for its ability to prevent advanced glycation end-product (AGE) formation. Among them, a careful examination of the NMR dataset of pedilanthocoumarin B led to a structural revision. Inspection of LC-DAD-MS(n) chromatograms allowed us to predict the presence of four new compounds, which were further isolated. Using spectroscopic methods (¹H-, (13)C- and 2D-NMR, HRMS, UV), these compounds were identified as new benzoyl substituted 4-phenylcoumarins (iso-pedilanthocoumarin B and neurophyllol C) and 4-(1-acetoxypropyl)coumarins cyclo F (ochrocarpins H and I).


Assuntos
Cumarínicos/química , Mammea/química , Casca de Planta/química , Extratos Vegetais/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
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