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1.
Food Res Int ; 167: 112678, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37087210

RESUMO

In this study, the capacity of eight essential oils (EOs), sage (Salvia officinalis), coriander (Coriandrum sativum), rosemary (Rosmarinus officinalis), black cumin (Nigella sativa), prickly juniper (Juniperus oxycedrus), geranium (Pelargonium graveolens), oregano (Origanum vulgare) and wormwood (Artemisia herba-alba), on the inhibition of NF-κB activation was screened at concentrations up to 0.25 µL/mL using THP-1 human macrophages bearing a NF-κB reporter. This screening selected coriander, geranium, and wormwood EOs as the most active, which later evidenced the ability to decrease over 50 % IL-6, IL-1ß, TNF-α and COX-2 mRNA expression in LPS-stimulated THP-1 macrophages. The chemical composition of selected EOs was performed by gas chromatography-mass spectrometry (GC-MS). The two major constituents (>50 % of each EO) were tested at the same concentrations presented in each EO. It was demonstrated that the major compound or the binary mixtures of the two major compounds could explain the anti-inflammatory effects reported for the crude EOs. Additionally, the selected EOs also inhibit>50 % caspase-1 activity. However, this effect could not be attributed to the major components (except for ß-citronellol/geranium oil, 40 %/65 % caspase-1 inhibition), suggesting, in addition to potential synergistic effects, the presence of minor compounds with caspase-1 inhibitory activity. These results demonstrated the potential use of the EOs obtained from Tunisian flora as valuable sources of anti-inflammatory agents providing beneficial health effects by reducing the levels of inflammatory mediators involved in the genesis of several diseases.


Assuntos
Óleos Voláteis , Origanum , Plantas Medicinais , Humanos , Óleos Voláteis/química , NF-kappa B , Macrófagos , Origanum/química , Anti-Inflamatórios/farmacologia , Caspases
2.
Chem Biodivers ; 20(5): e202300047, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36972029

RESUMO

The current study was conducted to investigate the chemical composition of Quercus canariensis flour acorns extracts as well as its biological activities in regards to the growing area using spectrophotometric and chromatographic techniques. The phenolic profile was composed of 19 compounds identified through HPLC-DAD analysis. Coumarin was the most abundant compound quantified in BniMtir, Nefza and ElGhorra and gallic (12.58-20.52 %), syringic (4.70-7.64 %) and trans-ferulic (2.28-2.94 %) acids were the abundant phenolic acids while kaempferol was the major flavonoid compounds quantified only in Quercus canariensis growing in BniMtir. On the other hand, Ain Snoussi acorn extract was characterized by its high content in luteolin-7-O-glucoside (58.46 %). The in-vitro antioxidant activities of the studied extracts were investigated and the results showed that Nefza ethanolic extract's has the highest activities. A bactericidal effect against Staphylococcus aureus was observed only by Elghorra population. On the other hand, Ain Snoussi acorn extract was efficient to inhibit growth of pathogenic bacteria, mentioned the highest activity against Escherichia coli. These results is the first study highlighted that zeen oak acorns are an excellent source of natural antioxidants and antibacterial compounds related to their lysozyme activity which could be exploited in the pharmaceutical and food sectors.


Assuntos
Quercus , Quercus/química , Farinha/análise , Tunísia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Fenóis/farmacologia , Fenóis/análise , Antioxidantes/farmacologia , Antioxidantes/análise , Antibacterianos/química
3.
Molecules ; 27(5)2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35268666

RESUMO

Myrtus communis L. essential oil (EO), mainly composed of myrtenyl acetate (30.6%), linalool (14.9%), α-pinene (11.10%) and 1,8-cineole or eucalyptol (9.9%), was microencapsulated with maltodextrin by emulsification and spray-drying, reaching a yield and efficiency of 43.7 and 48.7%, respectively. The microencapsulated myrtle EO (MMEO) was then evaluated regarding its gastroprotective activity in a model of ethanol/HCl-induced acute gastric ulcer in Wistar rats. Pretreatment with MMEO induced a remarkable inhibition of gastric lesions and acidity, correlated to high healing and protection percentages. Moreover, it exerted a potent anti-inflammatory effect on the gastric mucosa, counteracting EtOH-induced gastric lipoperoxidation and preventing the depletion of the antioxidant enzyme activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Taken together, the gastroprotective action of encapsulated MMEO may be multi-factorial, and ascribable, at least in parts, to its anti-inflammatory and antioxidant properties.


Assuntos
Antiulcerosos , Myrtus , Óleos Voláteis , Úlcera Gástrica , Animais , Antiulcerosos/farmacologia , Etanol/efeitos adversos , Mucosa Gástrica , Óleos Voláteis/uso terapêutico , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/patologia
4.
Arch Microbiol ; 204(1): 119, 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-34989872

RESUMO

The aim of this study was to investigate antimicrobial and antioxidant activities of different fractions obtained from edible Tunisian Ziziphus Lotus leaves of Tozeur region. Different organic extracts were tested: cyclohexane, dichloromethane, ethyl acetate, n-butanol and water. Bio-guided fractionation revealed that dichloromethane fraction is the most active against S. aureus and Methicillin-resistant S. aureus strains. Moreover, this fraction showed the highest antileishmanial activity with IC50 values of 20.55 ± 0.34 µg/mL and 15.37 ± 0.17 µg/mL against L. major and L. infantum, respectively. The potentialities of antibacterial and leishmanicidal activities found in dichloromethane could be explained by the presence of major flavonoids such as catechin, rutin and luteolin 7-O-glucoside as revealed by HPLC system. The observed moderate antifungal activity, which was only given by butanolic fraction against pathogen fungi, may be attributed to the presence of chlorogenic acid. Furthermore, dichloromethane and butanolic fraction showed a good DPPH (2,2-diphenyl-1-picryl hydrazyl) scavenging activity and Ferric reducing power. These results suggest that Ziziphus lotus leaf fractions might be used as antioxidant and antimicrobialagent.


Assuntos
Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Ziziphus , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Folhas de Planta , Staphylococcus aureus
5.
Biol Aujourdhui ; 215(3-4): 133-142, 2021.
Artigo em Francês | MEDLINE | ID: mdl-35275057

RESUMO

Since ancient times, plants have been the main source of bioactive molecules, such as phenolic compounds, capable of remedying various diseases. However, polyphenols' content and efficiency vary greatly as a function of several intrinsic and extrinsic factors. To optimize the procedure for the extraction of active molecules from the medicinal plant Verbena officinalis, effects of the plant origin, selected solvent, and extraction method were assessed. V. officinalis aerial parts were collected in two different regions of Tunisia (Bizerte and Ain Draham), and their bioactive molecules were extracted by maceration, decoction, and by the Soxhlet apparatus, either with water or with ethanol. Significant variability in the extracts' contents of phenolic compounds as well as their antioxidant and antimicrobial capacities were noted depending on the different studied factors. In particular, ethanol extracts were found to generally contain higher concentrations of phenolic compounds and more potent antioxidant capacities than water extracts. However, when tested against various pathogenic bacteria, water extracts were most often at least as active as ethanol extracts to inhibit bacteria growth in vitro. Finally, differences were also observed between V. officinalis samples from Bizerte compared to Ain Draham area. All of these results emphasize the need of adapting various parameters for the optimal extraction of bioactive molecules from a medicinal plant such as V. officinalis.


Title: Évaluation de différents procédés d'extraction des composés phénoliques d'une plante médicinale : Verbena officinalis. Abstract: Depuis la nuit des temps, les plantes ont été la source principale de molécules bioactives, tels les composés phénoliques, capables de remédier à diverses maladies. Cependant, le contenu et l'activité des polyphénols dépendent d'un certain nombre de facteurs intrinsèques et extrinsèques. Dans le but d'optimiser les procédés d'obtention des principes actifs de la verveine (Verbena officinalis), les effets de la provenance de la plante, du solvant et de la méthode d'extraction ont été évalués. Ainsi, la partie aérienne de V. officinalis a été collectée dans deux régions différentes de la Tunisie (Bizerte et Ain Draham). L'extraction a été réalisée par macération, décoction et par l'appareil de Soxhlet tantôt avec de l'eau tantôt avec de l'éthanol pur. Une variabilité significative des teneurs en composés phénoliques ainsi que des capacités antioxydantes et antimicrobiennes des extraits a été observée en fonction des facteurs étudiés. De manière générale, les extraits éthanoliques sont plus riches en composés phénoliques et présentent des activités antioxydantes plus fortes que les extraits aqueux. Cependant, vis-à-vis de différentes souches pathogènes, les extraits aqueux sont souvent au moins aussi puissants que les extraits éthanoliques pour inhiber la croissance bactérienne in vitro. De plus des différences notables sont observées selon que V. officinalis provient de la région de Bizerte ou d'Ain Draham. Ces résultats montrent que la prise en compte de plusieurs paramètres est nécessaire pour optimiser l'efficacité des procédures d'extraction des molécules bioactives de V. officinalis.


Assuntos
Plantas Medicinais , Verbena , Antioxidantes/farmacologia , Humanos , Fenóis/farmacologia , Extratos Vegetais/farmacologia
6.
Prep Biochem Biotechnol ; 50(9): 943-953, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32543278

RESUMO

Artemisia herba-alba (Aha) is an aromatic and medicinal plant rich in health-promoting flavonoids compounds that play an important role as antioxidant. For better utilization of this resource, the ultrasound-assisted extraction (UAE) of flavonoids and antiradical activities of obtained extracts from Aha using response surface methodology was assessed. A four-factor five-level central composite rotatable design was employed to discuss these extracting parameters: ethanol concentration (X1), temperature (X2), extraction time (X3) and solvent to sample ratio (X4). The optimum extraction conditions for simultaneous maximization of total flavonoids (TF) and scavenging activity were solvent concentration of 50%, temperature of 55 °C, extraction time of 50 min and solvent to sample ratio of 90 mL/g. Under these conditions, the experimental yield of TF and DPPH-radical scavenging activity IC50% were respectively 102.49 mg CE/g DM and 7 µg/mL. Additionally, good and moderate linear correlation was observed between antiradical activity and TF content (R2 = 0.709) which indicated that these compounds are responsible for antioxidant activity of Aha. When compared to the most conventional extraction, antioxidant activity and amounts of major flavonoids are enhanced when using UAE with reduced extraction time.


Assuntos
Artemisia/química , Flavonoides/isolamento & purificação , Sequestradores de Radicais Livres/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Compostos de Bifenilo/química , Fracionamento Químico , Flavonoides/química , Flavonoides/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Picratos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sonicação
7.
Biomolecules ; 10(2)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-32023949

RESUMO

The use of chemical herbicides could not only potentially induce negative impacts on the environment, animals, and human health, but also increase the weed resistance to herbicides. In this context, the use of plant extracts could be an interesting and natural alternative to chemical products. It is important to understand the mode of action of their bioactive compounds. This is why we have studied the herbicidal effect of Cynara cardunculus crude extract in terms of inhibition of weeds' seedling growth and its impact on physiological parameters of treated plantlets, like conductivity, dry weight, and fluorescence, and biochemical parameters linked to oxidative stress. We have observed that C. cardunculus crude extract induces oxidative stress in the treated plants and consequently disturbs the physiological and biochemical functions of the plant cells. We have investigated the herbicidal activity of three bioactive compounds, naringenin, myricitrin, and quercetin, from the C. cardunculus crude extract. In both pre- and post-emergence trials, naringenin and myricitrin were significantly more phytotoxic than quercetin. We suggest that their differential initial interaction with the plant's plasma membrane could be one of the main signals for electrolyte leakage and production of high levels of phenoxyl radicals.


Assuntos
Cynara/química , Flavanonas/química , Herbicidas/química , Estresse Oxidativo , Extratos Vegetais/química , Quercetina/química , Trifosfato de Adenosina/química , Agricultura , Membrana Celular/metabolismo , Condutividade Elétrica , Eletrólitos , Flavonoides/química , Peróxido de Hidrogênio/química , Peroxidação de Lipídeos , Malondialdeído/química , Fenóis , Fotossíntese , Plantas Daninhas
8.
Int J Food Sci Nutr ; 71(3): 307-314, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31394953

RESUMO

Argan oil is thought to be the most expensive edible oil worldwide. It is difficult to produce and the argan tree only grows in a limited geographical area, notably Morocco and Algeria. Because it is produced by mechanical means, argan oil contains "minor" components that might be endowed with healthful effects. We investigated in vivo the anti-inflammatory activities of argan oil and its unsaponifiable fraction, using diclofenac as the control, in a carrageenan-induced rat model of inflammation. Rats were given different amounts of argan oil or its unsaponifiable fraction, by gavage. We report that argan oil and its "minor" components effectively lessen the inflammatory actions of carrageenan. Far from being "pharmacological" the actions of argan oil are comparable with those of diclofenac in the short, i.e. 4 h term. Sustained consumption of argan oil might, therefore, contribute to lessen the burden of degenerative diseases associated with higher inflammatory status.


Assuntos
Anti-Inflamatórios/farmacologia , Óleos de Plantas/farmacologia , Animais , Anti-Inflamatórios/química , Edema/induzido quimicamente , Edema/prevenção & controle , Feminino , Camundongos , Óleos de Plantas/química
9.
Phytochem Anal ; 31(1): 37-45, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31313408

RESUMO

INTRODUCTION: The consumption of health-promoting products such as oil seeds may improve human health and prevent certain diseases. Carvi seeds have the potential to produce oil with nutritional and functional properties rich in active compounds. OBJECTIVE: To extract bioactive lipids from Carum carvi seeds using green methodologies. MATERIAL AND METHODS: Supercritical-carbon dioxide (Sc-CO2 ) and ethanol as co-solvent and bio-based solvent 2-methyltetrahydrofuran (MeTHF) were used to extract the oil from Carum carvi. The yield, the chemical composition, as well as antioxidant and anti-inflammatory activities of green extracted oils were investigated and compared to those obtained with conventional methods (hexane and Folch system). RESULTS: MeTHF extraction gave higher oil yield than that obtained by hexane. Fatty acids composition of the two obtained green extracted oils was similar to conventional extracted ones where petroselinic (39-43%), linoleic (29-31%) and oleic (19-21%) acids were the major compounds. Furthermore, MeTHF and Sc-CO2 green extracted oils were enriched of bioactive compounds including sterols (5.4 and 7.3 mg/g oil) and total polyphenols (9.3 and 7.6 mg GAE/g oil) which were correlated to enhanced antiradical capacity. Moreover, the green extracted oils exhibited high anti-inflammatory capacity inhibiting nitric oxide (NO) release in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages with IC50 values of 28 and 24 µg/mL. CONCLUSION: Green solvents are a good alternative to petroleum solvents to recover oil from carvi seeds with high amount of nutritionally important fatty acids, along with significant antioxidant and anti-inflammatory potential.


Assuntos
Carum , Cromatografia com Fluido Supercrítico , Anti-Inflamatórios , Antioxidantes , Dióxido de Carbono , Humanos , Óleos , Óleos de Plantas , Sementes , Solventes
10.
Nat Prod Res ; 34(24): 3545-3547, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30835550

RESUMO

The aim of the present study was to evaluate the phenolic contents in capsule and root methanolic extracts of Euphorbia retusa followed by identification of phenolic on capsule extracts through high-performance liquid chromatography (HPLC- DAD) for the first time. Likewise, the antioxidant activity of both extracts was investigated by using Cupric reducing antioxidant capacity (CUPRAC). The result implies that E. retusa capsules have the highest phenolic and flavonoid contents with 105.33 ± 7.75 µg GAE.mg-1 extract 19.95 ± 0.96 µg QEs.mg-1 extract; respectively and the highest activity in CUPRAC assay with epigallocatechin 3-O-Gallate was the major flavonoid. Thus, our findings indicate that E. restusa capsules may be valorized in industrial fields.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Euphorbia/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Cápsulas , Catequina/análogos & derivados , Catequina/análise , Cromatografia Líquida de Alta Pressão , Avaliação Pré-Clínica de Medicamentos , Flavonoides/análise , Fenóis/análise , Fenóis/química , Extratos Vegetais/química
11.
J Virol ; 93(10)2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30842319

RESUMO

Recent emergence of direct-acting antivirals (DAAs) targeting hepatitis C virus (HCV) proteins has considerably enhanced the success of antiviral therapy. However, the appearance of DAA-resistant-associated variants is a cause of treatment failure, and the high cost of DAAs renders the therapy not accessible in countries with inadequate medical infrastructures. Therefore, the search for new inhibitors with a lower cost of production should be pursued. In this context, the crude extract of Juncus maritimus Lam. was shown to exhibit high antiviral activity against HCV in cell culture. Bio-guided fractionation allowed the isolation and identification of the active compound, dehydrojuncusol. A time-of-addition assay showed that dehydrojuncusol significantly inhibited HCV infection when added after virus inoculation of HCV genotype 2a (50% effective concentration [EC50] = 1.35 µM). This antiviral activity was confirmed with an HCV subgenomic replicon, and no effect on HCV pseudoparticle entry was observed. Antiviral activity of dehydrojuncusol was also demonstrated in primary human hepatocytes. No in vitro toxicity was observed at active concentrations. Dehydrojuncusol is also efficient on HCV genotype 3a and can be used in combination with sofosbuvir. Interestingly, dehydrojuncusol was able to inhibit RNA replication of two frequent daclatasvir-resistant mutants (L31M or Y93H in NS5A). Finally, mutants resistant to dehydrojuncusol were obtained and showed that the HCV NS5A protein is the target of the molecule. In conclusion, dehydrojuncusol, a natural compound extracted from J. maritimus, inhibits infection of different HCV genotypes by targeting the NS5A protein and is active against resistant HCV variants frequently found in patients with treatment failure.IMPORTANCE Tens of millions of people are infected with hepatitis C virus (HCV) worldwide. Recently marketed direct-acting antivirals (DAAs) targeting HCV proteins have enhanced the efficacy of treatment. However, due to its high cost, this new therapy is not accessible to the vast majority of infected patients. Furthermore, treatment failures have also been reported due to the appearance of viral resistance. Here, we report on the identification of a new HCV inhibitor, dehydrojuncusol, that targets HCV NS5A and is able to inhibit RNA replication of replicons harboring resistance mutations to anti-NS5A DAAs used in current therapy. Dehydrojuncusol is a natural compound isolated from Juncus maritimus, a halophilic plant species that is very common in coastlines worldwide. This molecule might serve as a lead for the development of a new therapy that is more accessible to hepatitis C patients in the future.


Assuntos
Hepacivirus/efeitos dos fármacos , Fenantrenos/farmacologia , Replicação Viral/efeitos dos fármacos , Antivirais/farmacologia , Linhagem Celular , Farmacorresistência Viral/genética , Genótipo , Células HEK293 , Hepacivirus/genética , Hepatite C/genética , Hepatite C/virologia , Hepatite C Crônica/virologia , Hepatócitos/virologia , Humanos , Fenantrenos/metabolismo , Fenetilaminas/farmacologia , Extratos Vegetais/farmacologia , Inibidores de Proteases/farmacologia , Replicon/efeitos dos fármacos , Rizoma
12.
Molecules ; 23(9)2018 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-30158452

RESUMO

This work focuses on the variability of Retama raetam (Forssk.) Webb bioactive compounds as a function of the plant cycle. The main results showed that it exhibited the highest percentage of polyunsaturated fatty acids, along with superior levels of vitamin C and total phenolic compounds (66.49%, 645.6 mg·100 g-¹ FW and 23.9 mg GAE·g-¹, respectively) at the vegetative stage. Instead, at the flowering and mature fruiting stages, R. raetam (Forssk.) Webb exhibited notable contents of proline (25.4 µmol·g-¹ DW) and carotenoids (27.2 µg·g-¹ FW), respectively. The gathered data concerning the antioxidant activity highlighted the effectiveness of the vegetative stage in comparison to the other periods. Actually, IC50 and EC50 values of the hydromethanolic extract obtained from the plant shoots at the vegetative stage were of 23, 380, 410, 1160 and 960 µg·mL-1 (DPPH• and ABTS•+ radicals scavenging activity, reducing power, chelating power and ß-carotene bleaching activity, respectively). Furthermore, the four studied stages showed appreciable antibacterial capacities against human pathogens with a higher efficiency of the vegetative stage extract. Finally, the LC-DAD-ESI/MSn analysis revealed the predominance of isoflavonoids as main class of phenolic compounds and demonstrates that individual phenolic biosynthesis was clearly different as a function of plant growth. These findings highlight that reaching the optimum efficiency of R. raetam (Forssk.) Webb is closely linked to the physiological stage.


Assuntos
Fabaceae/crescimento & desenvolvimento , Extratos Vegetais/análise , Antibacterianos/análise , Antioxidantes/análise , Fabaceae/química , Metaboloma , Brotos de Planta/química
13.
Food Chem ; 257: 206-210, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29622199

RESUMO

In this investigation, we aimed to study, for the first time, the phenolic composition of Pistacia lentiscus seed oils from different growing areas. Extraction of the phenolic fraction from oils was done by methanol/water. Phenolic profiles were determined using chromatographic analysis by High Performance Liquid Chromatography (HPLC-DAD/MSD) and its quantification was done using an internal standard which is unidentified in the studied oil (syringic acid). Forty phenolic compounds were quantified and only eighteen of them were identified. The eight studied oils showed different phenolic profiles. The total phenols amount varied from 538.03 mg/kg oil in Jbel Masour oils to 4260.57 mg/kg oil in oils from Kef Erraai. The highest amount of secoiridoids was reached by Bouchoucha oil containing 366.71 mg/kg oil of Oleuropein aglycon. Oils from Kef Erraai locality contained the highest concentrations in flavonols (377.44 mg/kg oil) and in phenolic acids (2762.67 mg/kg oil).


Assuntos
Cromatografia Líquida de Alta Pressão , Fenóis/análise , Pistacia/metabolismo , Óleos de Plantas/química , Flavonóis/análise , Iridoides/análise , Pistacia/química , Análise de Componente Principal , Sementes/química , Sementes/metabolismo
14.
Int J Biol Macromol ; 114: 830-835, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29626601

RESUMO

Mounting evidence indicates soluble Aß42 oligomers as the most toxic species causing neuronal death which leads to the onset and progression of Alzheimer disease (AD). Recently, it has been found that neurotoxic Aß42 oligomers grow from monomeric species or arise following secondary nucleation by preformed mature fibrils. Thus, the use of natural compounds such as polyphenols to hinder the growth or to remodel Aß42 fibrils is one of the most promising strategies for AD treatment. In our previous study, we showed that 1, 2, 4-trihydroxynaphthalene-2-O-ß-d-glucopyranoside (THNG) inhibits Aß42 aggregation during the early steps of the aggregation process, inhibits its conformational change to a ß-sheet-rich structure, decreases its polymerization, inhibits its fibrillogenisis and reduces oxidative stress and aggregate cytotoxicity. Here, we used different spectroscopic and cell culture methods to check the effect of THNG on fibrils disaggregation. We showed that THNG binds to mature Aß42 fibrils, rearrange their secondary structure, and remodels them into non-amyloid, less toxic, species by inhibiting their interaction with the plasma membrane. Our findings reveal that THNG is a good agent to remodel amyloid fibrils and could be used as a starting molecular scaffold to design new anti-AD drugs.


Assuntos
Peptídeos beta-Amiloides/química , Amiloide/efeitos dos fármacos , Lawsonia (Planta)/química , Fragmentos de Peptídeos/química , Amiloide/toxicidade , Peptídeos beta-Amiloides/toxicidade , Linhagem Celular Tumoral , Dicroísmo Circular , Avaliação Pré-Clínica de Medicamentos , Transferência Ressonante de Energia de Fluorescência , Gangliosídeo G(M1)/análise , Humanos , Microdomínios da Membrana , Microscopia Eletrônica , Estrutura Molecular , Neuroblastoma/patologia , Fragmentos de Peptídeos/toxicidade , Folhas de Planta/química
15.
Biofactors ; 44(3): 272-280, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29582494

RESUMO

Presently, misfolding and aggregation of amyloid-ß42 (Aß42 ) are considered early events in Alzheimer's disease (AD) pathogenesis. The use of natural products to inhibit the aggregation process and to protect cells from cytotoxicity of early aggregate grown at the onset of the aggregation path is one of the promising strategies against AD. Recently, we have purified a new powerful antioxidant and inhibitor of Aß42 aggregation from the leaves of Lawsonia inermis. The new compound was identified as a new Lawsoniaside; 1,2,4-trihydroxynaphthalene-2-O-ß-D-glucopyranoside (THNG). Herein, we show that THNG interferes with Aß42 aggregation, inhibits its conformational change to a ß-sheet-rich structure, decreases its polymerization into large fibrillar species, reduces oxidative stress, and aggregate cytotoxicity. These results indicate that THNG has great potential as a neuroprotective and therapeutic agent against AD. © 2018 BioFactors, 44(3):272-280, 2018.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Glucosídeos/farmacologia , Lawsonia (Planta)/química , Naftalenos/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/antagonistas & inibidores , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/farmacologia , Benzotiazóis , Cálcio/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dicroísmo Circular , Glucosídeos/química , Glucosídeos/isolamento & purificação , Humanos , Naftalenos/química , Naftalenos/isolamento & purificação , Neurônios/citologia , Neurônios/metabolismo , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Extratos Vegetais/química , Agregados Proteicos/efeitos dos fármacos , Conformação Proteica em Folha beta , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Fluorescência , Tiazóis/química
16.
Braz. J. Pharm. Sci. (Online) ; 54(2): e17576, 2018. tab
Artigo em Inglês | LILACS | ID: biblio-951936

RESUMO

ABSTRACT The present study investigates the effect of cinnamon (Cinnamomum zeylanicumon) powder supplementation on glucose levels, lipid profiles, and oxidative stress parameters in alloxan-induced diabetic rats. Diabetes was induced in adult male Wistar rats via a single subcutaneous alloxan injection (15 mg/kg). Cinnamon powder was mixed with the standard feed of the rats in an amount of 5% for 28 consecutive days. Serum concentrations of total cholesterol (TC) and triglycerides (TG) were assayed at the end of the experimental period in all investigated groups. Anti-oxidative enzymes such as glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD) were sought in the serum and pancreas. Alloxan caused the fasting blood sugar level to increase. The administration of cinnamon blocked the increase of blood glucose. There was also a significant difference in the TG and TC levels between control and treated diabetic rats. In diabetic rats, cinnamon treatment restored the activities of SOD, CAT and GPx. These findings suggested that cinnamon has an anti-hyperglycemic effect, improves lipid profiles, and protect against damage induced by oxidative stress in the diabetic state.


Assuntos
Animais , Masculino , Ratos , Extratos Vegetais/análise , Cinnamomum zeylanicum/efeitos adversos , Diabetes Mellitus Experimental , Antioxidantes
17.
Biomed Pharmacother ; 95: 1404-1411, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28946188

RESUMO

Limoniastrum guyonianum is used in several regions of North Africa as a folk medicine. The objective of this study was to determine the in vitro antioxidant activities of L. guyonianum roots and their cytoprotective action on H2O2-challenged rat small intestine epithelial cells (IEC-6 cells). To assess the cytoprotective effect of L. guyonianum extract (LGE), IEC-6 cells were pre-incubated with different LGE concentrations. Then, IEC-6 cultures were exposed to 40µM H2O2 during 4h. Modulation of endogenous antioxidant system including SOD, CAT, MDA, GSH and the expression of possibly involved MAPKs was evaluated. Main results reported that L. guyonianum was rich in polyphenols and exhibited an important antioxidant activity as revealed by different tests (DPPH Assay, IC50=1.6µg/mL; ABTS+ test, IC50=27µg/mL; Fe-reducing power, EC50=44µg/mL). HPLC analysis showed that quercetin, catechin, and isorhamnetin-3-O-rutinoside were major phenolics. The exposure of IEC-6 cells to 40µM H2O2 during 4h resulted in oxidative stress manifested by (i) over 70% cell mortality, (ii) over-activity of CAT (246%), (iii) decrease in GSH level (10.4nmol/mg), (iv) excess in MDA content (18.4nmol/mg), and (v) a trigger of JNK phosphorylation. Pretreatment with LGE, especially at 0.25µg/mL, restored cell viability to 100%, and normal cell morphology in H2O2-chalenged cells. In addition, this extract maintained a high CAT activity, enhanced SOD capacity (120%) and increased GSH level (45.5nmol/mg). Furthermore, reducing cell death seems to be due to dephosphorylated JNK MAPK exerted by L. guyonianum bioactive compounds. In all, L. guyonianum components provided a cross-talk between regulatory pathways, implying their role as cytoprotector against oxidative stress.


Assuntos
Células Epiteliais/enzimologia , Células Epiteliais/patologia , Glutationa/metabolismo , Peróxido de Hidrogênio/toxicidade , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plumbaginaceae/química , Animais , Antioxidantes/farmacologia , Linhagem Celular , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Malondialdeído/metabolismo , Fenóis/análise , Fosforilação/efeitos dos fármacos , Raízes de Plantas/química , Ratos
18.
J Food Drug Anal ; 25(2): 350-359, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28911677

RESUMO

The antioxidant and antibacterial activities of phenolic compounds from cultivated and wild Tunisian Ruta chalepensis L. leaves, stems, and flowers were assessed. The leaves and the flowers exhibited high but similar total polyphenol, flavonoid, and tannin content. Moreover, two organs showed strong, although not significantly different, total antioxidant activity, 2,2-diphenyl-1-picrylhydrazyl scavenging ability, and reducing power. Investigation of the phenolic composition showed that vanillic acid and coumarin were the major compounds in the two organs, with higher percentages in the cultivated organs than in the spontaneous organs. Furthermore, R. chalepensis extracts showed marked antibacterial properties against human pathogen strains, and the activity was organ- and origin-dependent. Spontaneous stems had the strongest activity against Pseudomonas aeruginosa. From these results, it was concluded that domestication of Ruta did not significantly affect its chemical composition and consequently the possibility of using R. chalpensis organs as a potential source of natural antioxidants and as an antimicrobial agent in the food industry.


Assuntos
Ruta , Anti-Infecciosos , Antioxidantes , Compostos de Bifenilo , Picratos , Extratos Vegetais
19.
J Food Drug Anal ; 25(2): 391-402, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28911682

RESUMO

In this study, the effects of salinity on growth, fatty acid, essential oil, and phenolic composition of cumin (Cuminum cyminum L.) seeds as well as the antioxidant activities of their extracts were investigated. Plants were treated with different concentrations of NaCl treatment: 0, 50, 75, and 125 mmoL. Plant growth was significantly reduced with the severity of saline treatment. This also caused important reductions in the seed yield and yield components. Besides, NaCl treatments affected fatty acid composition. Petroselinic and linoleic acids proportions diminished consistently with the increase in NaCl concentration, whereas palmitic acid proportion increased. Furthermore, NaCl enhanced essential oil production in C. cyminum seeds and induced marked changes on the essential oil quality. Essential oil chemotype was modified from γ-terpinene/1-phenyl-1,2 ethanediol in control to γ-terpinene/ß-pinene in salt stressed plants. Total polyphenol content was higher in treated seeds, and salinity improved the amount of individual phenolic compounds. Moreover, antioxidant activities of the extracts were determined by four different test systems, namely 2,2-diphenyl-1-picrylhydrazyl, ß-carotene/linoleic acid chelating, and reducing power assays. The highest antioxidant activities were reveled in severe stressed plants. In this case, cumin seeds produced under saline conditions may function as a potential source of essential oil and antioxidant compounds, which could support the utilization of this plant in a large field of applications such as food industry.


Assuntos
Cuminum , Tolerância ao Sal , Antioxidantes , Ácidos Graxos , Cromatografia Gasosa-Espectrometria de Massas , Monoterpenos , Óleos Voláteis , Extratos Vegetais , Sementes
20.
Food Res Int ; 99(Pt 1): 702-712, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28784534

RESUMO

In this work, LC-ESI-TOF-MS and GC-EI-MS were used to assess the potential of Artemisia herba alba as a source of health-promoting constituents. Besides, the antioxidant, the antimicrobial and the cytotoxic potentials were evaluated. A total of 86 metabolites, including C-glycosylated and methylated flavones, quinic acid derivatives, coumarins, sesquiterpenes lactones, terpenoids, fatty acids, carbohydrates, organic acids and alkaloids were identified, sixty five of them were reported for the first time in A. herba alba. The main compounds were di-O-caffeoylquinic acids, artemisinic acid, menthol, α-ketoglutaric acid, scopolin, isoschaftoside and sucrose. Furthermore, results showed that A. herba alba possess high total antioxidant activity (Total antioxidant activity=423mg gallic acid equivalent/g dry weight), strong potential anticancer capacity against MCF-7 breast cancer and HeLa human cervical cell lines (IC50 of 15 and 70µg/ml, respectively), and moderate antibacterial activity against S. aureus, B. thurigiensis and A. hydrophila. These results support the use of this plant as alternative bioactive ingredient for functional foods, dietary supplements or nutraceuticals.


Assuntos
Artemisia/química , Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Extratos Vegetais/química , Folhas de Planta/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Anticarcinógenos/análise , Antioxidantes/análise , Cumarínicos/análise , Flavonas/análise , Ácido Quínico/análise , Terpenos/análise
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