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1.
Molecules ; 27(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35744833

RESUMO

Acanthocereus tetragonus (L.) Hummelinck is used as an alternative food source in some Mexican communities. It has been shown that the young stems of A. tetragonus provide crude protein, fiber, and essential minerals for humans. In this work, we analyzed the phytochemical profile, the total phenolic content (TPC), and the antioxidant activity of cooked and crude samples of A. tetragonus to assess its functional metabolite contribution to humans. The phytochemical profile was analyzed using Ultra-High-Performance Liquid Chromatography coupled to High-Resolution Mass Spectrometry (UHPLC-PDA-HESI-Orbitrap-MS/MS). Under the proposed conditions, 35 metabolites were separated and tentatively identified. Of the separated metabolites, 16 occurred exclusively in cooked samples, 6 in crude samples, and 9 in both crude and cooked samples. Among the detected compounds, carboxylic acids, such as threonic, citric, and malic acids, phenolic acids, and glycosylated flavonoids (luteolin-O-rutinoside) were detected. The TPC and antioxidant activity were analyzed using the Folin-Ciocalteu method and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical inhibition method, respectively. The TPC and antioxidant activity were significantly reduced in the cooked samples. We found that some metabolites remained intact after the cooking process, suggesting that A. tetragonus represents a source of functional metabolites for people who consume this plant species.


Assuntos
Cactaceae , Espectrometria de Massas em Tandem , Antioxidantes/química , Cromatografia Líquida de Alta Pressão/métodos , Culinária , Flavonoides/química , Humanos , México , Fenóis/análise , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Espectrometria de Massas em Tandem/métodos
2.
J Enzyme Inhib Med Chem ; 36(1): 154-162, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33307873

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder that affects adult people whose treatment is palliative. Thus, we decided to test three dammarane triterpenes 1, 1a, 1b, and we determined that 1 and 1a inhibit ß-aggregation through thioflavine T rather than 1b. Since compound 1 was most active, we determined the interaction between α-synuclein and 1 at 50 µM (Kd) through microscale thermophoresis. Also, we observed differences in height and diameter of aggregates, and α-synuclein remains unfolded in the presence of 1. Also, aggregates treated with 1 do not provoke neurites' retraction in N2a cells previously induced by retinoic acid. Finally, we studied the potential sites of interaction between 1 with α-synuclein fibrils using molecular modelling. Docking experiments suggest that 1 preferably interact with the site 2 of α-synuclein through hydrogen bonds with residues Y39 and T44.


Assuntos
Simulação de Acoplamento Molecular , Triterpenos/farmacologia , alfa-Sinucleína/antagonistas & inibidores , Animais , Sítios de Ligação/efeitos dos fármacos , Relação Dose-Resposta a Droga , Magnoliopsida/química , Camundongos , Conformação Molecular , Agregados Proteicos/efeitos dos fármacos , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/isolamento & purificação , Células Tumorais Cultivadas , alfa-Sinucleína/isolamento & purificação , alfa-Sinucleína/metabolismo , Damaranos
3.
Molecules ; 26(12)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205516

RESUMO

Neurodegenerative disorders, including Tauopathies that involve tau protein, base their pathological mechanism on forming proteinaceous aggregates, which has a deleterious effect on cells triggering an inflammatory response. Moreover, tau inhibitors can exert their mechanism of action through noncovalent and covalent interactions. Thus, Michael's addition appears as a feasible type of interaction involving an α, ß unsaturated carbonyl moiety to avoid pathological confirmation and further cytotoxicity. Moreover, we isolated three compounds from Antarctic lichens Cladonia cariosa and Himantormia lugubris: protolichesterinic acid (1), fumarprotocetraric acid (2), and lichesterinic acid (3). The maleimide cysteine labeling assay showed that compounds 1, 2, and 3 inhibit at 50 µM, but compounds 2 and 3 are statistically significant. Based on its inhibition capacity, we decided to test compound 2 further. Thus, our results suggest that compound 2 remodel soluble oligomers and diminish ß sheet content, as demonstrated through ThT experiments. Hence, we added externally treated oligomers with compound 2 to demonstrate that they are harmless in cell culture. First, the morphology of cells in the presence of aggregates does not suffer evident changes compared to the control. Additionally, the externally added aggregates do not provoke a substantial LDH release compared to the control, indicating that treated oligomers do not provoke membrane damage in cell culture compared with aggregates alone. Thus, in the present work, we demonstrated that Michael's acceptors found in lichens could serve as a scaffold to explore different mechanisms of action to turn tau aggregates into harmless species.


Assuntos
Fumaratos/farmacologia , Agregados Proteicos/efeitos dos fármacos , Proteínas tau/antagonistas & inibidores , Proteínas tau/metabolismo , 4-Butirolactona/análogos & derivados , 4-Butirolactona/farmacologia , Regiões Antárticas , Ascomicetos/metabolismo , Linhagem Celular Tumoral , Humanos , Líquens/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Parmeliaceae/metabolismo , Tauopatias/tratamento farmacológico , Tauopatias/metabolismo
4.
Molecules ; 26(9)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33921982

RESUMO

Fourteen coumarin-derived compounds modified at the C3 carbon of coumarin with an α,ß-unsaturated ketone were synthesized. These compounds may be designated as chalcocoumarins (3-cinnamoyl-2H-chromen-2-ones). Both chalcones and coumarins are recognized scaffolds in medicinal chemistry, showing diverse biological and pharmacological properties among which neuroprotective activities and multiple enzyme inhibition, including mitochondrial enzyme systems, stand out. The evaluation of monoamine oxidase B (MAO-B) inhibitors has aroused considerable interest as therapeutic agents for neurodegenerative diseases such as Parkinson's. Of the fourteen chalcocumarins evaluated here against MAO-B, ChC4 showed the strongest activity in vitro, with IC50 = 0.76 ± 0.08 µM. Computational docking, molecular dynamics and MM/GBSA studies, confirm that ChC4 binds very stably to the active rMAO-B site, explaining the experimental inhibition data.


Assuntos
Chalconas/química , Cumarínicos/química , Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/farmacologia , Monoaminoxidase/química , Animais , Sítios de Ligação , Relação Dose-Resposta a Droga , Humanos , Ligantes , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Ligação Proteica , Ratos , Relação Estrutura-Atividade
5.
Molecules ; 25(13)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32630065

RESUMO

In the present work, the anthelmintic activity (AA) of ethanolic extracts obtained from Gliricidia sepium, Leucaena leucocephala, and Pithecellobium dulce was evaluated using the third-stage-larval (L3) exsheathment inhibition test (LEIT) and egg hatch test (EHT) on Haemonchus contortus. Extracts were tested at concentrations of 0.3, 0.6, 1.2, 2.5, 5.0, 10, 20, and 40 mg/mL. The larval exsheathment inhibition (LEI) results showed that G. sepium achieved the highest average inhibition of 91.2%, compared with 44.6% for P. dulce and 41.0% for L. leucocephala at a concentration of 40 mg/mL; the corresponding IC50 values were 22.4, 41.7, and 43.3 mg/mL, respectively. The rates of egg hatching inhibition (EHI) at a concentration of 5 mg/mL were 99.5% for G. sepium, 64.2% for P. dulce, and 54% for L. leucocephala; the corresponding IC50 values were 1.9 mg/mL for G. sepium, 3.9 mg/mL for P. dulce, and 4.3 mg/mL for L. leucocephala. The species extracts studied here were also analyzed by ultra-high performance liquid chromatography and Orbitrap high resolution mass spectrometry (UHPLC-Q/Orbitrap/MS/MS), resulting in the compounds' identification associated with AA. Glycosylated flavonoids and methoxyphenols were observed in all three species: fatty acids in G. sepium and P. dulce; phenylpropanoids, anthraquinone glycosides, amino acids and glycosylated phenolic acids in G. sepium; and flavonoids in L. leucocephala. Comparatively, G. sepium presented a greater diversity of compounds potentially active against the control of gastrointestinal nematodes, which was associated with the results obtained in the applied tests.


Assuntos
Anti-Helmínticos/farmacologia , Fabaceae/química , Fabaceae/classificação , Flavonoides/farmacologia , Haemonchus/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Extratos Vegetais/farmacologia , Animais , Cromatografia Líquida de Alta Pressão , Haemonchus/efeitos dos fármacos , Técnicas In Vitro , Larva/efeitos dos fármacos , Espectrometria de Massas em Tandem
6.
Molecules ; 24(4)2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30781375

RESUMO

Chromatographic separation combined with mass spectrometry is a powerful tool for the characterization of plant metabolites because of its high sensitivity and selectivity. In this work, the phytochemical profile of aerial and radicular parts of Coryphantha macromeris (Engelm.) Britton & Rose growing under greenhouse conditions was qualitatively investigated for the first time by means of modern ultra-high-performance liquid chromatography⁻tandem mass spectrometry (UHPLC-PDA-HESI-Orbitrap-MS/MS). The UHPLC-PDA-HESI-Orbitrap-MS/MS analysis indicated a high complexity in phenolic metabolites. In our investigation, 69 compounds were detected and 60 of them were identified. Among detected compounds, several phenolic acids, phenolic glycosides, and organic acids were found. Within this diversity, 26 metabolites were exclusively detected in the aerial part, and 19 in the roots. Twenty-four metabolites occurred in both plant parts. According to the relative abundance of peaks in the chromatogram, ferulic and piscidic acids and their derivatives may correspond to one of the main phenolic compounds of C. macromeris. Our results contribute to the phytochemical knowledge regarding C. macromeris and its potential applications in the pharmaceutical and cosmetic industries. Besides, some metabolites and their fragmentation patterns are reported here for the first time for cacti species.


Assuntos
Cactaceae/química , Flavonoides/análise , Fenóis/análise , Extratos Vegetais/análise , Cactaceae/metabolismo , Cromatografia Líquida de Alta Pressão , Metaboloma , Compostos Fitoquímicos/análise , Metabolismo Secundário , Espectrometria de Massas em Tandem
7.
Molecules ; 24(9)2019 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-31035428

RESUMO

Mulinum crassifolium Phil. (Apiaceae) is an endemic shrub from Chile commonly used as infusion in traditional medicine to treat diabetes, bronchial and intestinal disorders and stomach ailments, including ulcers. From the EtOAc extract of this plant, the new mulinane-type diterpenoids 3 and 5 were isolated along with three known diterpenoids. The gastroprotective effect of the infusion of the plant was assayed to support the traditional use and a fast HPLC analysis using high resolution techniques was performed to identify the bioactive constituents. The EtOAc extract and the edible infusion showed gastroprotective effect at 100 mg/kg in the HCl/EtOH induced gastric ulcer model in mice, reducing lesions by 33% and 74%, respectively. Finally, a metabolomic profiling based on UHPLC-ESI-MS/HRMS of the edible infusion was performed and thirty-five compounds were tentatively identified including quercetin, caffeic acid, apigenine glucoside, p-coumaric acid, chlorogenic acids, and caffeoylquinic acids, which have been associated previously with gastroprotective and antiulcer properties. This scientific evidence can support the contribution of polyphenols in the gastroprotective activity of the edible infusion of this plant, and can validate at least in part, its ethnopharmacological use.


Assuntos
Apiaceae/química , Cromatografia Líquida de Alta Pressão , Diterpenos/química , Diterpenos/farmacologia , Trato Gastrointestinal/efeitos dos fármacos , Espectrometria de Massas , Extratos Vegetais/química , Animais , Metaboloma , Metabolômica , Camundongos , Estrutura Molecular
8.
Molecules ; 24(4)2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30769848

RESUMO

Extracts of bled resin from Azorella compacta, of the Azorelloideae family from the Andes (>4000 m), were analyzed by gas chromatography-mass spectrometry. The mass spectra of the dominant compounds of the resin and its hydrogenation products were documented. The most abundant compounds were oxygenated diterpenoids, namely mulinadien-20-oic (Δ11,13 and Δ11,14) acids, azorell-13-en-20-oic acid, 13α,14ß-dihydroxymulin-11-en-20-oic acid, and azorellanol, with a group of azorellenes and mulinadienes. The mass spectra of the novel diterpenoid hydrocarbons with the azorellane and mulinane skeletons were also presented. This study documents the molecular diversity of these diterpenoid classes, and could be of great utility for future organic geochemical, environmental, archeological, pharmaceutical, and forensic chemistry studies.


Assuntos
Apiaceae/química , Diterpenos/química , Altitude , Apiaceae/crescimento & desenvolvimento , Apiaceae/metabolismo , Biomarcadores/química , Diterpenos/isolamento & purificação , Diterpenos/metabolismo
9.
J Enzyme Inhib Med Chem ; 33(1): 936-944, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29734888

RESUMO

UHPLC/ESI/MS identification of organic compounds is the first step in the majority of screening techniques for the characterization of biologically active metabolites in natural sources. This paper describes a method for the fast identification and characterisation of secondary metabolites in Leptocarpha rivularis DC. (Palo negro) extracts by HPLC/UV (DAD)-Mass Spectrometry (HPLC/MS). The plant is used for the treatment of several diseases since pre-hispanic Mapuche times. Thirty-seven compounds were detected in the aqueous edible extract for the first time including 4 sesquiterpenes, 10 flavonoids, 9 oxylipins, 2 organic acids, and 11 phenolic acids. In addition, phenolic content antioxidant and cholinesterase inhibitory activities were measured for the first time using the edible infusion. The total polyphenol content of the infusion was 230.76 ± 2.5 mmol GAE/kg dry weight, while the antioxidant activity was 176.51 ± 28.84; 195.28 ± 4.83; and 223.92 ± 2.95 mmol TE/kg dry weight, for the DPPH, ABTS, and FRAP assays, respectively. The cholinesterase inhibitory activity was 7.38 ± 0.03 and 5.74 ± 0.06 mmol GALAE/kg, for the inhibition of acetylcholinesterase AChE and BChE, respectively, showing that this plant is a candidate for the isolation of compounds that can be useful for the treatment of neurodegenerative diseases. Furthermore, this plant could serve also as a raw material for the production of dietary supplements, due to its content of polyphenolic compounds.


Assuntos
Antioxidantes/farmacologia , Asteraceae/química , Produtos Biológicos/farmacologia , Compostos de Bifenilo/antagonistas & inibidores , Inibidores da Colinesterase/farmacologia , Picratos/antagonistas & inibidores , Acetilcolinesterase/metabolismo , Antioxidantes/química , Antioxidantes/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Inibidores da Colinesterase/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Hidroxibenzoatos/química , Hidroxibenzoatos/isolamento & purificação , Hidroxibenzoatos/farmacologia , Estrutura Molecular , Oxilipinas/química , Oxilipinas/isolamento & purificação , Oxilipinas/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade
10.
Molecules ; 23(9)2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-30223578

RESUMO

Forty-three metabolites including several methoxylated flavonoids, tremetones, and ent-clerodane diterpenes were accurately identified for the first time in the ethanolic extract of P. quadrangularis by means of hyphenated UHPLC-quadrupole Orbitrap mass spectrometry, and seven isolated compounds were tested regarding gastroprotective activity using the HCl/EtOH-induced lesion model in mice. A new tremetone (compound 6) is reported based on spectroscopic evidence. The isolated clerodanes and tremetones showed gastroprotective activity in a mouse model, evidenced by compound 7 (p-coumaroyloxytremetone), which showed the highest gastroprotective activity (76%), which was higher than the control drug lansoprazole (72%). Our findings revealed that several constituents of this plant have gastroprotective activity, and particularly, p-coumaroyloxytremetone could be considered as a lead molecule to explore new gastroprotective agents. This plant is a rich source of biologically active tremetones and terpenoids which can support the ethnobotanical use of the plant.


Assuntos
Antiulcerosos/administração & dosagem , Asteraceae/química , Benzofuranos/administração & dosagem , Diterpenos Clerodânicos/administração & dosagem , Úlcera Gástrica/tratamento farmacológico , Animais , Antiulcerosos/química , Antiulcerosos/farmacologia , Benzofuranos/química , Benzofuranos/farmacologia , Modelos Animais de Doenças , Diterpenos Clerodânicos/química , Diterpenos Clerodânicos/farmacologia , Etanol/efeitos adversos , Ácido Clorídrico/efeitos adversos , Lansoprazol/administração & dosagem , Lansoprazol/uso terapêutico , Camundongos , Estrutura Molecular , Extratos Vegetais/química , Úlcera Gástrica/induzido quimicamente
11.
J Enzyme Inhib Med Chem ; 32(1): 945-953, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28701064

RESUMO

Alzheimer's disease is a common tauopathy where fibril formation and aggregates are the hallmark of the disease. Efforts targeting amyloid-ß plaques have succeeded to remove plaques but failed in clinical trials to improve cognition; thus, the current therapeutic strategy is at preventing tau aggregation. Here, we demonstrated that four phenolic diterpenoids and rosmarinic acid inhibit fibrillization. Since, rosmarinic acid was the most active compound, we observe morphological changes in atomic force microscopy images after treatment. Hence, rosmarinic acid leads to a decrease in amide regions I and III, indicating that rosmarinic acid prevents ß-sheet assembly. Molecular docking study inside the steric zipper model of the hexapeptide 306VQIVYK311 involved in fibrillization and ß sheet formation, suggests that rosmarinic acid binds to the steric zipper with similar chemical interactions with respect to those observed for orange G, a known pharmacofore for amyloid.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Cinamatos/farmacologia , Depsídeos/farmacologia , Proteínas tau/antagonistas & inibidores , Doença de Alzheimer/metabolismo , Cinamatos/química , Cinamatos/isolamento & purificação , Depsídeos/química , Depsídeos/isolamento & purificação , Relação Dose-Resposta a Droga , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Agregados Proteicos/efeitos dos fármacos , Conformação Proteica em Folha beta , Rosmarinus/química , Relação Estrutura-Atividade , Vibração , Proteínas tau/metabolismo , Ácido Rosmarínico
12.
Molecules ; 22(11)2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29084151

RESUMO

Lichens are symbiotic associations of fungi with microalgae and/or cyanobacteria. Lichens belonging to the Parmeliaceae family comprise 2700 species of lichens, including the Parmotrema genus which is composed of 300 species. The metabolites of this genus include depsides, depsidones, phenolics, polysaccharides, lipids, diphenylethers and dibenzofurans, which are responsible for the biological activities reported including antidiabetic, antihelmintic, anticancer, antioxidant, antibacterial, anti-inflammatory, antimitotic, antitumoral, antifungal, and antioxidant enzyme inhibitory. Due to scarce knowledge of metabolomic profiles of Parmotrema species (P. andinum and P. robustum), a full metabolome study based on ultra-high performance liquid chromatography- diode array detector-electrospray ionization-quadrupole-orbitrap-mass-spectrometry (UHPLC-DAD-ESI-Q-orbitrap MS) was performed for a comprehensive characterization of their substances. From the methanolic extracts of these species, a total of 54 metabolites were identified for the first time using this hyphenated technique, including thirty compounds in P. andinum, and thirty-seven in P. robustum. Moreover, two compounds were not identified as known compounds, and could be new structures, according to our data. This report shows that this technique is effective and accurate for rapid chemical identification of lichen substances and the compounds identified could serve as chemotaxonomic markers to differentiate these ruffle lichens.


Assuntos
Metabolômica/métodos , Metanol/química , Parmeliaceae/química , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
13.
Molecules ; 23(1)2017 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-29280946

RESUMO

Lichens are symbiotic associations of fungi with microalgae and/or cyanobacteria, which are considered among the slowest growing organisms, with strong tolerance to adverse environmental conditions. There are about 400 genera and 1600 species of lichens and those belonging to the Usnea genus comprise about 360 of these species. Usnea lichens have been used since ancient times as dyes, cosmetics, preservatives, deodorants and folk medicines. The phytochemistry of the Usnea genus includes more than 60 compounds which belong to the following classes: depsides, depsidones, depsones, lactones, quinones, phenolics, polysaccharides, fatty acids and dibenzofurans. Due to scarce knowledge of metabolomic profiles of Usnea species (U. barbata, U. antarctica, U. rubicunda and U. subfloridana), a study based on UHPLC-ESI-OT-MS-MS was performed for a comprehensive characterization of their secondary metabolites. From the methanolic extracts of these species a total of 73 metabolites were identified for the first time using this hyphenated technique, including 34 compounds in U. barbata, 21 in U. antarctica, 38 in U. rubicunda and 37 in U. subfloridana. Besides, a total of 13 metabolites were not identified and reported so far, and could be new according to our data analysis. This study showed that this hyphenated technique is rapid, effective and accurate for phytochemical identification of lichen metabolites and the data collected could be useful for chemotaxonomic studies.


Assuntos
Líquens/química , Metabolômica/métodos , Extratos Vegetais/análise , Espectrometria de Massas em Tandem/métodos , Usnea/química , Usnea/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Fungos , Metanol/química , Compostos Fitoquímicos/metabolismo , Extratos Vegetais/química
14.
Bioorg Med Chem Lett ; 26(14): 3220-3222, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27262597

RESUMO

Mulinane diterpenoids isolated from Azorella species have displayed gastroprotective effects in animal models. In this study we have transformed the main constituent, mulin-11,13-dien-20 oic acid from this plant using the filamentous fungus Mucor plumbeus and a ß-cyclodextrin inclusion complex and we have obtained two main products with good yields (33% and 15% for compound 4 and 5, respectively) for further preparation of semisynthetic derivatives to evaluate their gastroprotective effects. In addition, one of the compounds isolated from Azorella cuatrecasasii was new (9-epi-13α-hydroxymulinene 1). Six new derivatives 4a-4c and 5a-5c were then prepared by simple chemical transformations. The structures of all compounds were elucidated by spectroscopic means based on 1D and 2D-NMR techniques. Some 8 diterpenes were evaluated for their gastroprotective effects in the ethanol/HCl-induced ulcer model in mice at 20mg/kg. The highest gastroprotective activity was shown by 7α,16-dihydroxymulin-11,13-dien-20-oic acid 5, which was higher than the reference drug lansoprazole, while 16-hydroxymulin-11,13-dien-20-oic acid 4 was as active as lansoprazole.


Assuntos
Antiulcerosos/farmacologia , Apiaceae/química , Diterpenos/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Úlcera Gástrica/tratamento farmacológico , beta-Ciclodextrinas/farmacologia , Álcoois , Animais , Antiulcerosos/química , Antiulcerosos/isolamento & purificação , Modelos Animais de Doenças , Diterpenos/química , Diterpenos/isolamento & purificação , Relação Dose-Resposta a Droga , Mucosa Gástrica/patologia , Ácido Clorídrico , Camundongos , Conformação Molecular , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/patologia , Relação Estrutura-Atividade , beta-Ciclodextrinas/química
15.
Bioorg Med Chem Lett ; 26(23): 5732-5735, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27810240

RESUMO

Natural or synthetic coumarins showed gastroprotective and antiulcer activity in animal models. In this study, we have synthetized twenty coumarins using classic methods to evaluate their gastroprotective effects on the ethanol/HCl-induced gastric lesion model in mice at 20mg/kg. Among the coumarins synthetized, compounds 6 and 10 showed the greatest gastroprotective activity being as active as lansoprazole at 20mg/kg and reducing gastric lesions by 75 and 76%, respectively. Then, in a second experiment, compounds 6 and 10 were re-evaluated in order to understand the possible mode of gastroprotective activity. Regarding coumarin 6, the protective effect was reduced by pre-treatment of the mice with N-ethylmaleimide and l-NAME suggesting that sulfhydryl compounds and endogenous nitric oxide are involved in its gastroprotective activity. While for coumarin 10 the effect was reduced by pre-treatment with indomethacin suggesting that prostaglandins are positively involved in its gastroprotective activity.


Assuntos
Antiulcerosos/química , Antiulcerosos/uso terapêutico , Cumarínicos/química , Cumarínicos/uso terapêutico , Prostaglandinas/metabolismo , Úlcera Gástrica/tratamento farmacológico , Canais de Cátion TRPV/metabolismo , Animais , Antiulcerosos/farmacologia , Cumarínicos/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Úlcera Gástrica/metabolismo , Compostos de Sulfidrila/metabolismo
16.
Int J Mol Sci ; 17(8)2016 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-27548142

RESUMO

Liquid chromatography coupled with mass spectrometry is an outstanding methodology for fast analysis of phenolic compounds in biological samples. Twenty two compounds were quickly and accurately identified in the methanolic extract of the Antarctic lichen Ramalina terebrata for the first time using ultra high pressure liquid chromatography coupled with photodiode array detector and high resolution mass spectrometry (UHPLC-PDA-Q/Orbitrap/MS/MS). In addition, the extract and the four compounds isolated from this species were tested for the inhibitory activity of tau protein aggregation, which is a protein involved in Alzheimer's disease (AD). All compounds showed null activity with the exception of parietin, which it was able to inhibit aggregation process of tau in a concentration range between 3 µg/mL (10 µM) to 28 µg/mL (100 µM). In addition, we show how parietin interact with tau (306)VQIVYK(311) hexapeptide inside of the microtubule binding domain (4R) with the help of molecular docking experiments. Finally, the constituents present in the methanolic extract could possibly contribute to the established anti-aggregation activity for this extract and this in-depth analysis of the chemical composition of R. terebrata could guide further research into its medicinal properties and potential uses.


Assuntos
Líquens/química , Extratos Vegetais/química , Espectrometria de Massas em Tandem/métodos , Proteínas tau/antagonistas & inibidores , Emodina/análogos & derivados , Emodina/química , Estrutura Molecular
17.
Molecules ; 21(3): 245, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26907248

RESUMO

Mass spectrometry has become a method of choice to characterize bioactive compounds in biological samples because of its sensitivity and selectivity. Hybrid ultra-HPLC hyphenated with Orbitrap mass analyzer is an innovative state of the art technology that allows fast and accurate metabolomic analyses. In this work the metabolites of a Chilean mistletoe endemic to the VIII region of Chile were investigated for the first time using UHPLC mass analysis (UHPLC-PDA-HESI-Orbitrap MS(n)). The anthocyanins, together with the non-pigmented phenolics were fingerprinted and correlated with the antioxidant capacities measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and total content of phenolics, flavonoids and anthocyanins measured by spectroscopic methods. Six anthocyanins were identified, and among them, the 3-O-glycosides of delphinidin and cyanidin were the major ones. In addition, several phenolic acids (including feruloylquinic acid, feruloyl glucose, chlorogenic acid) and several flavonols (luteolin, quercetin, apigenin, isorhamnetin and glycoside derivatives) were also identified. The mistletoe leaves showed the highest antioxidant activity as measured by the DPPH radical bleaching, ferric reducing antioxidant power and superoxide anion scavenging activity tests (13.38 ± 0.47 µg/mL, 125.32 ± 5.96 µmolTE/g DW and 84.06 ± 4.59 at 100 µg/mL, respectively).


Assuntos
Antocianinas/química , Antioxidantes/química , Flavonoides/química , Flavonóis/química , Hidroxibenzoatos/química , Erva-de-Passarinho/química , Antocianinas/isolamento & purificação , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Chile , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/isolamento & purificação , Flavonóis/isolamento & purificação , Hidroxibenzoatos/isolamento & purificação , Picratos/antagonistas & inibidores , Extratos Vegetais/química , Folhas de Planta/química , Espectrometria de Massas em Tandem/métodos
18.
Molecules ; 21(1): 92, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26784158

RESUMO

A small Chilean variety of pears growing in the town of Toconao, an oasis located at the northeastern edge of the Salar de Atacama, northern Chile, was studied by means of modern PDA and high resolution mass spectral data (UHPLC-PDA-HESI-orbitrap-MS/MS). In addition, the antioxidant features of the fruits were compared with the varieties Packhman's Triumph and Abate Fetel and correlated with the presence of phenolic compounds. The non-pigmented phenolics were fingerprinted and related to the antioxidant capacities measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and total content of phenolics and flavonoids measured by spectroscopic methods. The machine allowed a fast separation of 15 min employing a flow rate of 1 mL per minute and could accurately identify 25 compounds, including several isorhamnetin derivatives and phenolic acids, present in the peel and pulps of this Chilean variety for the first time. The compounds were monitored using a wavelength range of 210-800 nm. The native small Chilean pear showed the highest antioxidant activity measured as the bleaching of the DPPH radical, the ferric reducing antioxidant power and superoxide anion scavenging activity (8.61 ± 0.65 µg/mL, 712.63 ± 12.12 micromols trolox equivalents (µmol/TE)/100 g FW, and 82.89% ± 2.52% at 100 µg/mL, respectively).


Assuntos
Antioxidantes/isolamento & purificação , Flavonoides/isolamento & purificação , Frutas/química , Fenóis/isolamento & purificação , Pyrus/química , Quercetina/análogos & derivados , Antioxidantes/química , Antioxidantes/metabolismo , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química , Chile , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Clima Desértico , Flavonoides/biossíntese , Flavonoides/química , Fenóis/química , Fenóis/metabolismo , Picratos/antagonistas & inibidores , Picratos/química , Extratos Vegetais/química , Pyrus/metabolismo , Quercetina/biossíntese , Quercetina/química , Quercetina/isolamento & purificação , Superóxidos/antagonistas & inibidores , Superóxidos/química , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos
19.
Bioorg Med Chem Lett ; 25(14): 2813-7, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26009162

RESUMO

Seventeen compounds (2-18) synthetized from the diterpenoid ent-beyer-15-en-18-ol (1) isolated from aerial part of Baccharis tola were tested for their gastroprotective activity on the model of HCl/EtOH-induced gastric lesions in mice. Furthermore cytotoxicity test toward fibroblasts and AGS cells were performed. The results showed that compound 1 (ED50=50 mg/kg), 2, 6 and 13 were the most active regarding gastroprotective activity. Compounds 8-10 and 17-18 showed the lowest cytotoxicity toward fibroblasts and AGS cells. Regarding to mode of gastroprotective action, the effect elicited by 6 (50 mg/kg) was reversed by Indomethacin but not by N-ethylmaleimide, N(G)-nitro-L-arginine methyl ester or ruthenium red, which suggests that prostaglandins are involved in the mode of gastroprotective action of 6.


Assuntos
Abietanos/química , Antiulcerosos/química , Suco Gástrico/metabolismo , Prostaglandinas/farmacologia , Compostos de Sulfidrila/farmacologia , Abietanos/isolamento & purificação , Abietanos/farmacologia , Animais , Antiulcerosos/isolamento & purificação , Antiulcerosos/farmacologia , Baccharis/química , Baccharis/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Humanos , Indometacina/farmacologia , Camundongos , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico
20.
J Nat Prod ; 78(4): 919-23, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25732560

RESUMO

Four new nitroasterric acid derivatives, pseudogymnoascins A-C (1-3) and 3-nitroasterric acid (4), along with the two known compounds questin and pyriculamide, were obtained from the cultures of a Pseudogymnoascus sp. fungus isolated from an Antarctic marine sponge belonging to the genus Hymeniacidon. The structures of the new compounds were determined by extensive NMR and MS analyses. These compounds are the first nitro derivatives of the known fungal metabolite asterric acid. Several asterric acid derivatives isolated from other fungal strains have shown antibacterial and antifungal activities. However, the new compounds described in this work were inactive against a panel of bacteria and fungi (MIC > 64 µg/mL).


Assuntos
Ascomicetos/química , Nitrocompostos/isolamento & purificação , Éteres Fenílicos/isolamento & purificação , Poríferos/microbiologia , Animais , Regiões Antárticas , Antibacterianos/química , Antifúngicos/isolamento & purificação , Testes de Sensibilidade Microbiana , Estrutura Molecular , Nitrocompostos/química , Nitrocompostos/farmacologia , Ressonância Magnética Nuclear Biomolecular , Éteres Fenílicos/química , Éteres Fenílicos/farmacologia
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