Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Bioorg Chem ; 120: 105576, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34979447

RESUMO

OBJECTIVE: Caffeine has been studied as a potentiating agent in chemotherapy against some types of cancer, but there are few reports on its effects on melanoma. This study aimed to investigate caffeine's ability to enhance the effects of dacarbazine in vitro. MATERIALS AND METHODS: Murine melanoma B16F10 cells were treated 24 h with 1-40 µM caffeine. We evaluated cytotoxicity, DNA damage, apoptosis, and oxidative lesion induced by dacarbazine associated with caffeine. The metabolization of these drugs, as well as immunocytochemical labeling, were also evaluated. CONCLUSIONS: The pre-treatment with caffeine showed to be more effective. Caffeine potentiated dacarbazine-induced cytotoxic effects by increasing dacarbazine biotransformation, apoptosis, DNA damage, and malondialdehyde levels; also, caffeine reduced Ki67 and ERK1/2 nuclear labeling and increased p53 labeling in B16F10 cells. In our experiment, caffeine promoted modifications associated with dacarbazine metabolism by viable cells potentiating this antineoplastic drug. These promising results should be further evaluated in experimental models in vivo.


Assuntos
Antineoplásicos , Melanoma , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Cafeína/farmacologia , Linhagem Celular Tumoral , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , Melanoma/tratamento farmacológico , Camundongos
2.
Phytother Res ; 35(2): 888-897, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32924205

RESUMO

Breast cancer is the second most common malignancy among women. Ilex paraguariensis A. St. Hil, known as yerba mate, is widely consumed in southern Brazil as a hot infusion drink known as chimarrão. This herb has a complex chemical composition and is rich in antioxidants, which may interfere in the course of chronic inflammatory diseases as breast cancer. This study investigated the impact of chimarrão consumption on the clinicopathological profile of women with breast cancer attended at Francisco Beltrão Cancer Hospital, Paraná, Brazil. Blood antioxidants and caffeine profiles were assessed. Decreases in reduced glutathione and metallothionein levels, and increase in catalase activity were observed among breast cancer patients that were chimarrão consumers. The levels of circulating caffeine in breast cancer patients with luminal A tumors were higher than those in patients with luminal B and HER-2 subtypes. Furthermore, overweight patients presented higher caffeine levels than the eutrophic ones. It was found positive associations between chimarrão intake and high body mass index, and chimarrão intake and menopause at diagnosis. Altogether, these findings suggest that chimarrão consumption affects the blood antioxidants of breast cancer patients, and that the caffeine present in this mixture may favor the development of tumor of good prognosis. HIGHLIGHTS: Chimarrão consumption may affect the course of chronic inflammatory diseases, as breast cancer. Chimarrão intake changed blood antioxidants in breast cancer patients who were current consumers when compared to the non-consumers ones. High levels of caffeine were detected in patients bearing luminal A tumors, suggesting a protective role.


Assuntos
Antioxidantes/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Cafeína/uso terapêutico , Folhas de Planta/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
3.
Planta ; 251(4): 83, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32189086

RESUMO

MAIN CONCLUSION: Plant growth-promoting bacteria association improved the enzymatic and non-enzymatic antioxidant pathways in Neotropical trees under drought, which led to lower oxidative damage and enhanced drought tolerance in these trees. Water deficit is associated with oxidative stress in plant cells and may, thus, negatively affect the establishment of tree seedlings in reforestation areas. The association with plant growth-promoting bacteria (PGPB) is known to enhance the antioxidant response of crops, but this strategy has not been tested in seedlings of Neotropical trees. We evaluated the effects of inoculation with two PGPB (Azospirillum brasilense and Bacillus sp.) on the antioxidant metabolism of Cecropia pachystachya and Cariniana estrellensis seedlings submitted to drought. We measured the activity of antioxidant enzymes and the content of non-enzymatic antioxidants in leaves, and biometrical parameters of the seedlings. In both tree species, drought decreased the activity of antioxidant enzymes and the content of non-enzymatic antioxidant compounds. For C. pachystachya, the enzymatic and non-enzymatic pathways were mostly influenced by A. brasilense inoculation, which enhanced ascorbate peroxidase (APX) and superoxide dismutase activities and positively affected the level of non-enzymatic antioxidant compounds. In C. estrellensis, A. brasilense inoculation enhanced APX activity. However, A. brasilense and Bacillus sp. inoculation had more influence on the non-enzymatic pathway, as both bacteria induced a greater accumulation of secondary compounds (such as chlorogenic acid, gallic acid, rutin and synapic acid) compared to that in non-inoculated plants under drought. For both species, PGPB improved biometrical parameters related to drought tolerance, as specific leaf area and leaf-area ratio. Our results demonstrate that PGPB induced antioxidant mechanisms in drought-stressed Neotropical trees, increasing drought tolerance. Thus, PGPB inoculation provides a biotechnological alternative to improve the success of reforestation programmes.


Assuntos
Antioxidantes/metabolismo , Desenvolvimento Vegetal , Estresse Fisiológico , Árvores/metabolismo , Ascorbato Peroxidases/metabolismo , Azospirillum brasilense/metabolismo , Cecropia/metabolismo , Cecropia/microbiologia , Secas , Lecythidaceae/metabolismo , Lecythidaceae/microbiologia , Estresse Oxidativo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Plântula/metabolismo , Plântula/microbiologia , Árvores/microbiologia
4.
Mediators Inflamm ; 2015: 392918, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26074677

RESUMO

Leishmania amazonensis (L. amazonensis) infection can cause severe local and diffuse injuries in humans, a condition clinically known as American cutaneous leishmaniasis (ACL). Currently, the therapeutic approach for ACL is based on Glucantime, which shows high toxicity and poor effectiveness. Therefore, ACL remains a neglected disease with limited options for treatment. Herein, the in vitro antiprotozoal effect and mechanisms of the diterpene kaurenoic acid [ent-kaur-16-en-19-oic acid] (KA) against L. amazonensis were investigated. KA exhibited a direct antileishmanial effect on L. amazonensis promastigotes. Importantly, KA also reduced the intracellular number of amastigote forms and percentage of infected peritoneal macrophages of BALB/c mice. Mechanistically, KA treatment reestablished the production of nitric oxide (NO) in a constitutive NO synthase- (cNOS-) dependent manner, subverting the NO-depleting escape mechanism of L. amazonensis. Furthermore, KA induced increased production of IL-1ß and expression of the inflammasome-activating component NLRP12. These findings demonstrate the leishmanicidal capability of KA against L. amazonensis in macrophage culture by triggering a NLRP12/IL-1ß/cNOS/NO mechanism.


Assuntos
Antiprotozoários/farmacologia , Diterpenos/farmacologia , Interleucina-1beta/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Leishmania mexicana/efeitos dos fármacos , Leishmania mexicana/patogenicidade , Macrófagos Peritoneais/parasitologia , Óxido Nítrico/metabolismo , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Transdução de Sinais/efeitos dos fármacos
5.
Int J Food Sci Nutr ; 63(8): 978-86, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22621769

RESUMO

The objective of this study was to optimize the extraction of different isoflavone forms (glycosidic, malonyl-glycosidic, aglycone and total) from defatted cotyledon soy flour using the simplex-centroid experimental design with four solvents of varying polarity (water, acetone, ethanol and acetonitrile). The obtained extracts were then analysed by high-performance liquid chromatography. The profile of the different soy isoflavones forms varied with different extractions solvents. Varying the solvent or mixture used, the extraction of different isoflavones was optimized using the centroid-simplex mixture design. The special cubic model best fitted to the four solvents and its combination for soy isoflavones extraction. For glycosidic isoflavones extraction, the polar ternary mixture (water, acetone and acetonitrile) achieved the best extraction; malonyl-glycosidic forms were better extracted with mixtures of water, acetone and ethanol. Aglycone isoflavones, water and acetone mixture were best extracted and total isoflavones, the best solvents were ternary mixture of water, acetone and ethanol.


Assuntos
Isoflavonas/isolamento & purificação , Modelos Químicos , Fitoestrógenos/isolamento & purificação , Extratos Vegetais/química , Alimentos de Soja/análise , Cromatografia Líquida de Alta Pressão , Cotilédone/química , Técnicas Eletroquímicas , Glicosídeos/análise , Glicosídeos/química , Glicosídeos/isolamento & purificação , Isoflavonas/análise , Isoflavonas/química , Limite de Detecção , Fitoestrógenos/análise , Fitoestrógenos/química , Extratos Vegetais/isolamento & purificação , Reprodutibilidade dos Testes , Solubilidade , Solventes/química , Glycine max/química , Estatística como Assunto
6.
Environ Technol ; 43(11): 1672-1683, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33151819

RESUMO

Pesticides present in water resources can cause adverse health effects even in low concentrations, due to their bio-accumulative character. Therefore, the challenge for drinking water production increases, due to the limitations of conventional water treatment technologies in the removal of small molecular weight dissolved compounds. This work aimed to provide technical and scientific support for the selection of pulverized activated carbon - PACs, granular activated carbon - GACs, and carbon nanotubes - CNT concerning atrazine - ATZ, simazine - SMZ, and diuron - DIU adsorption for application in water treatment plants, considering two forms of application commercial product - CP and analytical standard - SD. These forms of application were tested aiming to verify the influence of the purity of the products used in experiments on the adsorption efficiency. It was possible to verify the adsorption efficiencies were not guided only by the characteristics of the adsorptive materials used, and that the selection should not be carried out only based on the, specific superficial area - BET size and distribution of specific pore volume. The isotherms demonstrated that the parameter Kf associated with the results of the selection experiment can be considered an alternative technical tool of simple application and sufficient for this purpose. Also, the capacity of activated carbons - ACs and nanomaterials - NMs were affected by the application of the compounds, highlighting the importance of using commercial product - CP in scientific research and technical investigations.Hightlights The pesticides efficiency removal was affected due to the forms of application, SD and CP;The parameters IN and MBI were not decisive in the selection of the activated carbon;The main adsorption mechanism in all the materials was chemical;GAC was the most efficient adsorbent in the removal of the pesticides;An adequate adsorbent selection is crucial for satisfactory removal of pesticides in water.


Assuntos
Água Potável , Nanotubos de Carbono , Praguicidas , Poluentes Químicos da Água , Purificação da Água , Adsorção , Carvão Vegetal/química , Poluentes Químicos da Água/química , Purificação da Água/métodos
7.
Appl Biochem Biotechnol ; 190(1): 166-181, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31309413

RESUMO

The objective of this study was to evaluate the combination of physical and chemical pretreatments of wheat bran (WB) and oat hulls (OH) to obtain fermentable sugars and a residual solid fraction with increased susceptibility to enzymatic hydrolysis. High-pressure steam in an autoclave and ultrasonication were employed as pretreatments, and for both processes, WB and OH were treated with sulfuric acid (H2SO4), neutral medium (H2O) and sodium hydroxide (NaOH). Autoclave high-pressure steam in an acid medium was the most effective for the release of sugars (total sugars, xylose and glucose) from liquid hydrolysates and for the modification of the residual solid fraction. The cellulose content of the WB residual solid fraction increased from 7.19 to 39.17%, the lignin fraction of WB decreased from 6.40 to 3.21%, the cellulose content of OH increased from 31.16 to 61.53%, and lignin fraction of OH decreased from 18.12 to 7.24%, resulting in materials more susceptible to enzymatic hydrolysis.


Assuntos
Avena/química , Fibras na Dieta , Sonicação/métodos , Vapor , Açúcares/metabolismo , Fermentação , Hidrólise , Lignina/metabolismo , Microscopia Eletrônica de Varredura , Pressão , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
8.
Food Res Int ; 130: 108955, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32156395

RESUMO

Grapes are considered to be a major source of phenolic compounds as compared with other fruits. To improve the quality of table grapes, some techniques like thinning can be used. In addition, grape cultivars with distinct characteristics are directly linked to its phenolic profile. This study aimed to identify and quantify the phenolic compound profile and yield of the hybrid 'BRS Vitoria' seedless table grape under different bunch densities, using a combination of solid-phase extraction (SPE) methodologies and analytical high-performance liquid chromatography-diode array detector with tandem mass spectrometry (HPLC-DAD-ESI-MS/MS). A trial was carried out in 2016, in a commercial vineyard at Marialva, state of Parana (South Brazil). Three weeks after anthesis, the following bunch densities were evaluated: 4.0, 4.5, 5.0, 5.5, and 6 bunches per m2 (corresponding to an estimation of 16, 18, 20, 22, and 24 tons ha-1). The randomized block design was used as a statistical model with each treatment was replicated four times, with one vine per plot. Different characteristics were evaluated at harvest, e.g., soluble solids content (SS), total acidity (TA), maturation index (MI = SS/TA), bunch and berry masses, yield, as well hydroxycinnamic acid derivative (HCAD), anthocyanin, flavonol, and flavan-3-ol contents by HPLC-DAD-ESI-MS/MS analysis. The evaluated bunch densities did not interfere with the physicochemical characteristics of the berries, such as SS and MI. Under the density of 6.0 bunches per m2, the highest yield of 25 tons ha-1 was reached. Under all bunch densities, the phenolic profile presented the same compounds, but at different concentrations. Under a density of 5.0 bunches per m2, the compounds belonging to the anthocyanin and flavonol families were present in high concentrations. In contrast, at the densities of 4.0 and 4.5 bunches per m2, there was a reduction in the flavan-3-ol content. With respect to stilbenes, only the trans-piceid and its cis- isomer were detected. However, their concentrations had no significant influence on the evaluated bunch densities.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Fenóis/química , Espectrometria de Massas em Tandem/métodos , Vitis/crescimento & desenvolvimento , Ácidos Cumáricos/química , Produtos Agrícolas , Flavonóis/química , Proantocianidinas/química , Estilbenos/química
9.
Foods ; 7(7)2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30011817

RESUMO

Epicotyls from germinated soybeans (EGS) have great potential as sources of endogenous ß-glucosidase. Furthermore, this enzyme may improve the conversion of isoflavones into their corresponding aglycones. ß-Glucosidase may also increase the release of aglycones from the cell wall of the plant materials. Therefore, the aim of this work was to optimize both the extraction of ß-glucosidase from EGS and to further examine its application in defatted soybean cotyledon to improve the recovery of aglycones, which were evaluated by ultra-high performance liquid chromatography (UHPLC). A multistep optimization was carried out and the effects of temperature and pH were investigated by applying a central composite design. The linear effect of pH and the quadratic effect of pH and temperature were significant for the extraction of ß-glucosidase and recovery aglycones, respectively. Optimum extraction of ß-glucosidase from EGS occurred at 30 °C and pH 5.0. Furthermore, the maximum recovery of aglycones (98.7%), which occurred at 35 °C and pH 7.0⁻7.6 during 144 h of germination, increased 8.5 times with respect to the lowest concentration. The higher bioaccessibility of aglycones when compared with their conjugated counterparts is well substantiated. Therefore, the data provided in this contribution may be useful for enhancing the benefits of soybean, their products, and/or their processing by-products.

10.
Biomed Pharmacother ; 98: 662-672, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29294453

RESUMO

Leishmania (L.) amazonensis is the American Cutaneous Leishmaniasis-causing agents, and the available drugs for this disease present toxicity, low efficiency and difficulty of administration. Plants belong23ing to the Caryocar genus are found in Brazilian Cerrado, where fruits are used as food and in folk medicine, and previous studies showed several biological effects of extracts of this plant. The present work evaluated the leishmanicidal and immunomodulatory activity of ethyl acetate (EAC) and methanol (MET) C. coriaceum leaf extracts EAC and MET showed an antipromastigote effect after 24, 48 and 72 h. The extracts also induced loss of mitochondrial membrane potential, reactive oxygen species (ROS) production, damage to the plasma membrane, and phosphatidylserine exposure on promastigote forms, and most parasites were going through a late apoptosis-like process. The range of concentrations used did not alter the viability of peritoneal macrophages of BALB/c mice; therefore, we observed that the treatment with extracts was able to reduce the infection of this cells. Thereafter, the extracts were able to significantly improve the levels of TNFα, IL-6, MCP-1, and IL-10, and reduced the levels of MDA and ROS without interfering on NO levels released by infected macrophages. In addition, both EAC and MET up-regulated Nrf2/HO-1/Ferritin expression and reduced the labile iron pool in infected macrophages. Based on the data obtained, it is possible to infer that different solvent extracts of the C. coriaceum leaves exert leishmanicidal effect, acting on promastigote forms through apoptosis-like mechanisms and intracellular amastigote forms involving a Nrf2/HO-1 dependent antioxidant response, which culminates in a depletion of available iron for L. amazonensis replication.


Assuntos
Apoptose/efeitos dos fármacos , Ferritinas/metabolismo , Heme Oxigenase-1/metabolismo , Ferro/metabolismo , Leishmania/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Extratos Vegetais/farmacologia , Folhas de Planta/química , Animais , Antioxidantes/metabolismo , Ericales/química , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/metabolismo , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Espécies Reativas de Oxigênio/metabolismo
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa