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1.
Braz. J. Pharm. Sci. (Online) ; 57: e19023, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1345452

RESUMO

The ascorbyl methylsilanol pectinate (AMP) presents the same functional properties of ascorbic acid (AA). Besides antioxidant and depigmentant activity, the AMP presents silanol in its chemical structure. The aim of this work was to characterize and indentify the AMP alone and in cosmetic formulations. The following techniques were employed: Fourier Transform Infrared Spectrophotometry, particle size distributions, in vitro antioxidant activity with 2.2-diphenyl-1-picrylhydrazyl (DPPH) and Oxigen Radical Absorbance Capacity Assay and High Performace Liquid Chromatography (HPLC) (developed and validated method) for the active ingredient; Microscopy, HPLC and Normal Stability Assay (NSA) for the emulsions. Particle size distributions results showed that the average size of AMP was 1.0 µm and polydispersity index was 0.1. In DPPH assay AA and AMP were statistically the same. The value of ORAC obtained for AMP was 0.74 and for AA in the literature was 0.95. In the NSA the formulations were stable in conditions of 5.0 and 45.0 ± 2.0 ºC for 90 days. Adequate stability at ambient temperature out of reach of light was also observed. Thus, this works presented an acceptable method for quantification of AMP alone and in cosmetic formulations. AMP was an adequate choice for the incorporation in emulsions with antioxidant efficacy.


Assuntos
Eficácia/classificação , Emulsões/análise , Análise de Fourier , Antioxidantes/análise , Ácido Ascórbico/agonistas , Espectrofotometria Infravermelho/instrumentação , Técnicas In Vitro/métodos , Cromatografia Líquida de Alta Pressão/instrumentação
2.
J Biomed Mater Res B Appl Biomater ; 106(5): 1809-1817, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28914997

RESUMO

Proinflammatory cytokines and reactive oxygen species (ROS) are known to be involved in the initiation and progression of osteoarthritis (OA). New evidence clarifying the correlation between ROS and inflammation has indicated that oxidative stress can up-regulate inflammatory cytokines. l-Ascorbic acid (AA), an antioxidant, has been shown to have anti-inflammatory effects and improve matrix deposition in chondrocytes. The purpose of this study was to examine the effects of hyaluronic acid (HA; 100 µg/mL) supplemented with AA (50 µg/mL) on human normal and interleukin-1 beta-stimulated (IL-1ß, 10 ng/mL) chondrocytes. HA, AA, and HA + AA treatment did not change cell morphology, viability, proliferation, and glycosaminoglycan production in normal chondrocytes. HA, AA, and HA + AA, by contrast, partially restored viability and morphology of hypertrophic chondrocytes, and HA and HA + AA further decreased the cytotoxicity of IL-1ß. Real-time PCR revealed that AA and HA + AA had no substantial effects on unstimulated chondrocytes, except for down-regulation of matrix metalloproteinase (MMP)-9 mRNA levels. For IL-1ß-stimulated chondrocytes, significant down-regulation of IL-1ß, tumor necrosis factor-alpha (TNF-α), MMP-3, and MMP-9 mRNA expression was found when cells were cultured in HA-supplemented media. Moreover, HA + AA supplementation further significantly decreased MMP-3 and MMP-9 mRNA expression. The protein production of MMP-3 was decreased, with a significant difference between the HA + AA group and HA group. The antioxidant capacity and superoxide dismutases activity were also partially restored in stimulated chondrocytes. HA supplemented with AA modulates MMPs expression and antioxidant fuction in chondrocytes. AA may enhance the anticatabolic effects of HA on OA chondrocytes. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1809-1817, 2018.


Assuntos
Ácido Ascórbico/farmacologia , Condrócitos/enzimologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Ácido Hialurônico/farmacologia , Metaloproteinase 3 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/biossíntese , Osteoartrite/metabolismo , Idoso , Idoso de 80 Anos ou mais , Antioxidantes/farmacologia , Ácido Ascórbico/agonistas , Condrócitos/patologia , Sinergismo Farmacológico , Feminino , Humanos , Ácido Hialurônico/agonistas , Masculino , Pessoa de Meia-Idade , Osteoartrite/tratamento farmacológico , Osteoartrite/patologia , Fator de Necrose Tumoral alfa/biossíntese
3.
Redox Biol ; 11: 384-389, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28063380

RESUMO

Hydroxytyrosol (HT) is a main phenolic component of olive oil. In this study, we investigated the safety and effects produced by HT purified (99.5%) from olive mill waste. HT was administered at a daily dosage of 45mg for 8 weeks to volunteers with mild hyperlipidemia (n=14). We measured markers of cardiovascular disease risk, enzyme markers of several clinical conditions, hematology, antioxidant parameters, vitamins and minerals at baseline (T0), 4 weeks (T4) and 8 weeks (T8). The values obtained at T4 and T8 were compared with baseline. We found that the HT dose administered was safe and mostly did not influence markers of cardiovascular disease, blood lipids, inflammatory markers, liver or kidney functions and the electrolyte balance. Serum iron levels remained constant but a significant (P<0.05) decrease in ferritin at T4 and T8 was found. Serum folate and red blood cell folate levels were also reduced at T4 and T8. Finally, vitamin C increased by two-fold at T4 and T8 compared with levels at baseline. These results indicate a physiologically relevant antioxidant function for HT through increasing endogenous vitamin C levels.


Assuntos
Ácido Ascórbico/agonistas , Suplementos Nutricionais , Azeite de Oliva/química , Álcool Feniletílico/análogos & derivados , Adulto , Ácido Ascórbico/sangue , Pressão Sanguínea/fisiologia , Índice de Massa Corporal , Feminino , Ácido Fólico/sangue , Voluntários Saudáveis , Humanos , Ferro/sangue , Testes de Função Renal , Metabolismo dos Lipídeos , Lipídeos/sangue , Testes de Função Hepática , Masculino , Álcool Feniletílico/administração & dosagem , Álcool Feniletílico/isolamento & purificação
4.
Stem Cell Rev Rep ; 12(1): 140-55, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26454429

RESUMO

Glioblastoma multiforme is the most malignant tumor of the brain and is challenging to treat due to its highly invasive nature and heterogeneity. Malignant brain tumor displays high metabolic activity which perturbs its redox environment and in turn translates to high oxidative stress. Thus, pushing the oxidative stress level to achieve the maximum tolerable threshold that induces cell death is a potential strategy for cancer therapy. Previously, we have shown that gap junction inhibitor, carbenoxolone (CBX), is capable of enhancing tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) -induced apoptosis in glioma cells. Since CBX is known to induce oxidative stress, we hypothesized that the addition of another potent mediator of oxidative stress, powerful SOD mimic MnTnBuOE-2-PyP(5+) (MnBuOE), could further enhance TRAIL-driven therapeutic efficacy in glioma cells. Our results showed that combining TRAIL + CBX with MnBuOE significantly enhances cell death of glioma cell lines and this enhancement could be further potentiated by CBX pretreatment. MnBuOE-driven cytotoxicity is due to its ability to take advantage of oxidative stress imposed by CBX + TRAIL system, and enhance it in the presence of endogenous reductants, ascorbate and thiol, thereby producing cytotoxic H2O2, and in turn inducing death of glioma cells but not normal astrocytes. Most importantly, combination treatment significantly reduces viability of TRAIL-resistant Asian patient-derived glioma cells, thus demonstrating the potential clinical use of our therapeutic system. It was reported that H2O2 is involved in membrane depolarization-based sensitization of cancer cells toward TRAIL. MnBuOE is entering Clinical Trials as a normal brain radioprotector in glioma patients at Duke University increasing Clinical relevance of our studies.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Materiais Biomiméticos/farmacologia , Carbenoxolona/farmacologia , Metaloporfirinas/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Ácido Ascórbico/agonistas , Ácido Ascórbico/biossíntese , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Materiais Biomiméticos/síntese química , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Combinação de Medicamentos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Junções Comunicantes/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Peróxido de Hidrogênio/agonistas , Peróxido de Hidrogênio/metabolismo , Metaloporfirinas/síntese química , Especificidade de Órgãos , Estresse Oxidativo , Cultura Primária de Células , Compostos de Sulfidrila/agonistas , Compostos de Sulfidrila/metabolismo , Superóxido Dismutase/química
5.
PLoS One ; 10(12): e0144033, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26641473

RESUMO

Chagas' disease is an infection that is caused by the protozoan Trypanosoma cruzi, affecting millions of people worldwide. Because of severe side effects and variable efficacy, the current treatments for Chagas' disease are unsatisfactory, making the search for new chemotherapeutic agents essential. Previous studies have reported various biological activities of naphthoquinones, such as the trypanocidal and antitumor activity of vitamin K3. The combination of this vitamin with vitamin C exerted better effects against various cancer cells than when used alone. These effects have been attributed to an increase in reactive oxygen species generation. In the present study, we evaluated the activity of vitamin K3 and vitamin C, alone and in combination, against T. cruzi. The vitamin K3 + vitamin C combination exerted synergistic effects against three forms of T. cruzi, leading to morphological, ultrastructural, and functional changes by producing reactive species, decreasing reduced thiol groups, altering the cell cycle, causing lipid peroxidation, and forming autophagic vacuoles. Our hypothesis is that the vitamin K3 + vitamin C combination induces oxidative imbalance in T. cruzi, probably started by a redox cycling process that leads to parasite cell death.


Assuntos
Ácido Ascórbico/farmacologia , Trypanosoma cruzi/metabolismo , Vitamina K 3/farmacologia , Animais , Ácido Ascórbico/agonistas , Linhagem Celular , Doença de Chagas/tratamento farmacológico , Doença de Chagas/metabolismo , Sinergismo Farmacológico , Macaca mulatta , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Vitamina K 3/agonistas
6.
Sci Rep ; 5: 11433, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26073760

RESUMO

In this study, we examined the possible mechanisms of trehalose (Tre) in improving copper-stress (Cu-stress) tolerance in rice seedlings. Our findings indicated that pretreatment of rice seedlings with Tre enhanced the endogenous Tre level and significantly mitigated the toxic effects of excessive Cu on photosynthesis- and plant growth-related parameters. The improved tolerance induced by Tre could be attributed to its ability to reduce Cu uptake and decrease Cu-induced oxidative damage by lowering the accumulation of reactive oxygen species (ROS) and malondialdehyde in Cu-stressed plants. Tre counteracted the Cu-induced increase in proline and glutathione content, but significantly improved ascorbic acid content and redox status. The activities of major antioxidant enzymes were largely stimulated by Tre pretreatment in rice plants exposed to excessive Cu. Additionally, increased activities of glyoxalases I and II correlated with reduced levels of methylglyoxal in Tre-pretreated Cu-stressed rice plants. These results indicate that modifying the endogenous Tre content by Tre pretreatment improved Cu tolerance in rice plants by inhibiting Cu uptake and regulating the antioxidant and glyoxalase systems, and thereby demonstrated the important role of Tre in mitigating heavy metal toxicity. Our findings provide a solid foundation for developing metal toxicity-tolerant crops by genetic engineering of Tre biosynthesis.


Assuntos
Antioxidantes/farmacologia , Cobre/toxicidade , Oryza/efeitos dos fármacos , Plântula/efeitos dos fármacos , Trealose/farmacologia , Ácido Ascórbico/agonistas , Ácido Ascórbico/biossíntese , Transporte Biológico/efeitos dos fármacos , Glutationa/agonistas , Glutationa/biossíntese , Lactoilglutationa Liase/biossíntese , Malondialdeído/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Oxirredução , Estresse Oxidativo , Fotossíntese/efeitos dos fármacos , Prolina/agonistas , Prolina/biossíntese , Aldeído Pirúvico/antagonistas & inibidores , Aldeído Pirúvico/metabolismo , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Estresse Fisiológico , Tioléster Hidrolases/biossíntese
7.
Life Sci ; 80(3): 258-63, 2006 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-17045618

RESUMO

Altered membrane integrity has been suggested as a major factor in the development of cellular injury during myocardial necrosis. The present study was designed to investigate the effect of the combination of ferulic acid (FA) and ascorbic acid (AA) on lysosomal hydrolases and membrane-bound phosphatases during isoproterenol (ISO) induced myocardial necrosis in rats. Induction of rats with 1SO (150 mg/kg b.wt, i.p.) for 2 days resulted in a significant increase in the activities of lysosomal hydrolases (beta-D-glucuronidase, beta-D-galactosidase, beta-D-N-acetylglucosaminidase, acid phosphatase and cathepsin-D) in the heart and serum. A significant increase in plasma lactate level, cardiac levels of sodium, calcium and a decrease in cardiac level of potassium was also observed, which was paralleled by abnormal activities of membrane-bound phosphatases (Na(+)-K(+) ATPase, Ca(2+) ATPase and Mg(2+) ATPase) in the heart of ISO-administered rats. Pre-co-treatment with the combination of FA (20 mg/kg b.wt) and AA (80 mg/kg b.wt) orally for 6 days significantly attenuated these abnormalities and restored the levels to near normalcy when compared to individual drug treated groups. The combination of FA and AA preserved the membrane integrity by mitigating the oxidative stress and associated cellular damage more effectively when compared to individual treatment groups. In our study, the protection conferred by FA and AA might be through the nitric oxide pathway and by their ability of quenching free radicals. In conclusion, these findings indicate the synergistic modulation of lysosomal hydrolases and membrane phosphatases by the combination of FA and AA.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Membrana Celular/enzimologia , Ácidos Cumáricos/farmacologia , Lisossomos/enzimologia , Infarto do Miocárdio/enzimologia , Monoéster Fosfórico Hidrolases/metabolismo , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Antioxidantes/uso terapêutico , Ácido Ascórbico/agonistas , Ácido Ascórbico/uso terapêutico , Cardiotônicos/toxicidade , Membrana Celular/patologia , Ácidos Cumáricos/agonistas , Sinergismo Farmacológico , Radicais Livres/metabolismo , Isoproterenol/toxicidade , Lisossomos/patologia , Masculino , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/patologia , Miocárdio/enzimologia , Miocárdio/patologia , Necrose/induzido quimicamente , Necrose/enzimologia , Necrose/patologia , Óxido Nítrico/metabolismo , Estresse Oxidativo , Ratos , Ratos Wistar
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